Port: use SIZE_MAX as max size_t value

[babeltrace.git] / plugins / ctf / common / notif-iter / notif-iter.c

/*
 * Babeltrace - CTF notification iterator
 *
 * Copyright (c) 2015-2016 EfficiOS Inc. and Linux Foundation
 * Copyright (c) 2015-2016 Philippe Proulx <pproulx@efficios.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#define BT_LOG_TAG "PLUGIN-CTF-NOTIF-ITER"
#include "logging.h"

#include <stdint.h>
#include <inttypes.h>
#include <stdio.h>
#include <stddef.h>
#include <stdbool.h>
#include <assert.h>
#include <string.h>
#include <babeltrace/ctf-ir/field-types.h>
#include <babeltrace/ctf-ir/field-types-internal.h>
#include <babeltrace/ctf-ir/field-path.h>
#include <babeltrace/ctf-ir/field-path-internal.h>
#include <babeltrace/ctf-ir/fields.h>
#include <babeltrace/ctf-ir/stream-class.h>
#include <babeltrace/ctf-ir/packet.h>
#include <babeltrace/ctf-ir/stream.h>
#include <babeltrace/ctf-ir/clock-class.h>
#include <babeltrace/ctf-ir/event-class.h>
#include <babeltrace/graph/notification-packet.h>
#include <babeltrace/graph/notification-event.h>
#include <babeltrace/graph/notification-stream.h>
#include <babeltrace/graph/clock-class-priority-map.h>
#include <babeltrace/ref.h>
#include <glib.h>
#include <stdlib.h>

#include "notif-iter.h"
#include "../btr/btr.h"

struct bt_ctf_notif_iter;

/* A visit stack entry */
struct stack_entry {
        /*
         * Current base field, one of:
         *
         *   * string
         *   * structure
         *   * array
         *   * sequence
         *   * variant
         *
         * Field is owned by this.
         */
        struct bt_ctf_field *base;

        /* index of next field to set */
        size_t index;
};

/* Visit stack */
struct stack {
        /* Entries (struct stack_entry *) (top is last element) */
        GPtrArray *entries;
};

/* State */
enum state {
        STATE_INIT,
        STATE_DSCOPE_TRACE_PACKET_HEADER_BEGIN,
        STATE_DSCOPE_TRACE_PACKET_HEADER_CONTINUE,
        STATE_AFTER_TRACE_PACKET_HEADER,
        STATE_DSCOPE_STREAM_PACKET_CONTEXT_BEGIN,
        STATE_DSCOPE_STREAM_PACKET_CONTEXT_CONTINUE,
        STATE_AFTER_STREAM_PACKET_CONTEXT,
        STATE_EMIT_NOTIF_NEW_PACKET,
        STATE_DSCOPE_STREAM_EVENT_HEADER_BEGIN,
        STATE_DSCOPE_STREAM_EVENT_HEADER_CONTINUE,
        STATE_AFTER_STREAM_EVENT_HEADER,
        STATE_DSCOPE_STREAM_EVENT_CONTEXT_BEGIN,
        STATE_DSCOPE_STREAM_EVENT_CONTEXT_CONTINUE,
        STATE_DSCOPE_EVENT_CONTEXT_BEGIN,
        STATE_DSCOPE_EVENT_CONTEXT_CONTINUE,
        STATE_DSCOPE_EVENT_PAYLOAD_BEGIN,
        STATE_DSCOPE_EVENT_PAYLOAD_CONTINUE,
        STATE_EMIT_NOTIF_EVENT,
        STATE_EMIT_NOTIF_END_OF_PACKET,
        STATE_SKIP_PACKET_PADDING,
};

struct trace_field_path_cache {
        /*
         * Indexes of the stream_id and stream_instance_id field in the packet
         * header structure, -1 if unset.
         */
        int stream_id;
        int stream_instance_id;
};

struct stream_class_field_path_cache {
        /*
         * Indexes of the v and id fields in the stream event header structure,
         * -1 if unset.
         */
        int v;
        int id;

        /*
         * index of the timestamp_end, packet_size and content_size fields in
         * the stream packet context structure. Set to -1 if the fields were
         * not found.
         */
        int timestamp_end;
        int packet_size;
        int content_size;
};

struct field_cb_override {
        enum bt_ctf_btr_status (* func)(void *value,
                        struct bt_ctf_field_type *type, void *data);
        void *data;
};

/* CTF notification iterator */
struct bt_ctf_notif_iter {
        /* Visit stack */
        struct stack *stack;

        /*
         * Current dynamic scope field pointer.
         *
         * This is set when a dynamic scope field is first created by
         * btr_compound_begin_cb(). It points to one of the fields in
         * dscopes below.
         */
        struct bt_ctf_field **cur_dscope_field;

        /* Trace and classes (owned by this) */
        struct {
                struct bt_ctf_trace *trace;
                struct bt_ctf_stream_class *stream_class;
                struct bt_ctf_event_class *event_class;
        } meta;

        /* Current packet (NULL if not created yet) */
        struct bt_ctf_packet *packet;

        /* Current stream (NULL if not set yet) */
        struct bt_ctf_stream *stream;

        /*
         * Current timestamp_end field (to consider before switching packets).
         */
        struct bt_ctf_field *cur_timestamp_end;

        /* Database of current dynamic scopes (owned by this) */
        struct {
                struct bt_ctf_field *trace_packet_header;
                struct bt_ctf_field *stream_packet_context;
                struct bt_ctf_field *stream_event_header;
                struct bt_ctf_field *stream_event_context;
                struct bt_ctf_field *event_context;
                struct bt_ctf_field *event_payload;
        } dscopes;

        /*
         * Special field overrides.
         *
         * Overrides are used to implement the behaviours of special fields such
         * as "timestamp_end" (which must be ignored until the end of the
         * packet), "id" (event id) which can be present multiple times and must
         * be updated multiple time.
         *
         * This should be used to implement the behaviour of integer fields
         * mapped to clocks and other "tagged" fields (in CTF 2).
         *
         * bt_ctf_field_type to struct field_cb_override
         */
        GHashTable *field_overrides;

        /* Current state */
        enum state state;

        /* Current medium buffer data */
        struct {
                /* Last address provided by medium */
                const uint8_t *addr;

                /* Buffer size provided by medium (bytes) */
                size_t sz;

                /* Offset within whole packet of addr (bits) */
                size_t packet_offset;

                /* Current position from addr (bits) */
                size_t at;

                /* Position of the last event header from addr (bits) */
                size_t last_eh_at;
        } buf;

        /* Binary type reader */
        struct bt_ctf_btr *btr;

        /* Current medium data */
        struct {
                struct bt_ctf_notif_iter_medium_ops medops;
                size_t max_request_sz;
                void *data;
        } medium;

        /* Current packet size (bits) (-1 if unknown) */
        int64_t cur_packet_size;

        /* Current content size (bits) (-1 if unknown) */
        int64_t cur_content_size;

        /* bt_ctf_clock_class to uint64_t. */
        GHashTable *clock_states;

        /*
         * Cache of the trace-constant field paths (event header type)
         * associated to the current trace.
         */
        struct trace_field_path_cache trace_field_path_cache;

        /*
         * Field path cache associated with the current stream class.
         * Ownership of this structure belongs to the field_path_caches HT.
         */
        struct stream_class_field_path_cache *cur_sc_field_path_cache;

        /* bt_ctf_stream_class to struct stream_class_field_path_cache. */
        GHashTable *sc_field_path_caches;
};

static inline
const char *state_string(enum state state)
{
        switch (state) {
        case STATE_INIT:
                return "STATE_INIT";
        case STATE_DSCOPE_TRACE_PACKET_HEADER_BEGIN:
                return "STATE_DSCOPE_TRACE_PACKET_HEADER_BEGIN";
        case STATE_DSCOPE_TRACE_PACKET_HEADER_CONTINUE:
                return "STATE_DSCOPE_TRACE_PACKET_HEADER_CONTINUE";
        case STATE_AFTER_TRACE_PACKET_HEADER:
                return "STATE_AFTER_TRACE_PACKET_HEADER";
        case STATE_DSCOPE_STREAM_PACKET_CONTEXT_BEGIN:
                return "STATE_DSCOPE_STREAM_PACKET_CONTEXT_BEGIN";
        case STATE_DSCOPE_STREAM_PACKET_CONTEXT_CONTINUE:
                return "STATE_DSCOPE_STREAM_PACKET_CONTEXT_CONTINUE";
        case STATE_AFTER_STREAM_PACKET_CONTEXT:
                return "STATE_AFTER_STREAM_PACKET_CONTEXT";
        case STATE_EMIT_NOTIF_NEW_PACKET:
                return "STATE_EMIT_NOTIF_NEW_PACKET";
        case STATE_DSCOPE_STREAM_EVENT_HEADER_BEGIN:
                return "STATE_DSCOPE_STREAM_EVENT_HEADER_BEGIN";
        case STATE_DSCOPE_STREAM_EVENT_HEADER_CONTINUE:
                return "STATE_DSCOPE_STREAM_EVENT_HEADER_CONTINUE";
        case STATE_AFTER_STREAM_EVENT_HEADER:
                return "STATE_AFTER_STREAM_EVENT_HEADER";
        case STATE_DSCOPE_STREAM_EVENT_CONTEXT_BEGIN:
                return "STATE_DSCOPE_STREAM_EVENT_CONTEXT_BEGIN";
        case STATE_DSCOPE_STREAM_EVENT_CONTEXT_CONTINUE:
                return "STATE_DSCOPE_STREAM_EVENT_CONTEXT_CONTINUE";
        case STATE_DSCOPE_EVENT_CONTEXT_BEGIN:
                return "STATE_DSCOPE_EVENT_CONTEXT_BEGIN";
        case STATE_DSCOPE_EVENT_CONTEXT_CONTINUE:
                return "STATE_DSCOPE_EVENT_CONTEXT_CONTINUE";
        case STATE_DSCOPE_EVENT_PAYLOAD_BEGIN:
                return "STATE_DSCOPE_EVENT_PAYLOAD_BEGIN";
        case STATE_DSCOPE_EVENT_PAYLOAD_CONTINUE:
                return "STATE_DSCOPE_EVENT_PAYLOAD_CONTINUE";
        case STATE_EMIT_NOTIF_EVENT:
                return "STATE_EMIT_NOTIF_EVENT";
        case STATE_EMIT_NOTIF_END_OF_PACKET:
                return "STATE_EMIT_NOTIF_END_OF_PACKET";
        case STATE_SKIP_PACKET_PADDING:
                return "STATE_SKIP_PACKET_PADDING";
        default:
                return "(unknown)";
        }
}

static
int bt_ctf_notif_iter_switch_packet(struct bt_ctf_notif_iter *notit);

static
enum bt_ctf_btr_status btr_timestamp_end_cb(void *value,
                struct bt_ctf_field_type *type, void *data);

static
void stack_entry_free_func(gpointer data)
{
        struct stack_entry *entry = data;

        bt_put(entry->base);
        g_free(entry);
}

static
struct stack *stack_new(struct bt_ctf_notif_iter *notit)
{
        struct stack *stack = NULL;

        stack = g_new0(struct stack, 1);
        if (!stack) {
                BT_LOGE_STR("Failed to allocate one stack.");
                goto error;
        }

        stack->entries = g_ptr_array_new_with_free_func(stack_entry_free_func);
        if (!stack->entries) {
                BT_LOGE_STR("Failed to allocate a GPtrArray.");
                goto error;
        }

        BT_LOGD("Created stack: notit-addr=%p, stack-addr=%p", notit, stack);
        return stack;

error:
        g_free(stack);
        return NULL;
}

static
void stack_destroy(struct stack *stack)
{
        assert(stack);
        BT_LOGD("Destroying stack: addr=%p", stack);
        g_ptr_array_free(stack->entries, TRUE);
        g_free(stack);
}

static
int stack_push(struct stack *stack, struct bt_ctf_field *base)
{
        int ret = 0;
        struct stack_entry *entry;

        assert(stack);
        assert(base);
        BT_LOGV("Pushing base field on stack: stack-addr=%p, "
                "stack-size-before=%u, stack-size-after=%u",
                stack, stack->entries->len, stack->entries->len + 1);
        entry = g_new0(struct stack_entry, 1);
        if (!entry) {
                BT_LOGE_STR("Failed to allocate one stack entry.");
                ret = -1;
                goto end;
        }

        entry->base = bt_get(base);
        g_ptr_array_add(stack->entries, entry);

end:
        return ret;
}

static inline
unsigned int stack_size(struct stack *stack)
{
        assert(stack);

        return stack->entries->len;
}

static
void stack_pop(struct stack *stack)
{
        assert(stack);
        assert(stack_size(stack));
        BT_LOGV("Popping from stack: "
                "stack-addr=%p, stack-size-before=%u, stack-size-after=%u",
                stack, stack->entries->len, stack->entries->len - 1);
        g_ptr_array_remove_index(stack->entries, stack->entries->len - 1);
}

static inline
struct stack_entry *stack_top(struct stack *stack)
{
        assert(stack);
        assert(stack_size(stack));

        return g_ptr_array_index(stack->entries, stack->entries->len - 1);
}

static inline
bool stack_empty(struct stack *stack)
{
        return stack_size(stack) == 0;
}

static
void stack_clear(struct stack *stack)
{
        assert(stack);

        if (!stack_empty(stack)) {
                BT_LOGV("Clearing stack: stack-addr=%p, stack-size=%u",
                        stack, stack->entries->len);
                g_ptr_array_remove_range(stack->entries, 0, stack_size(stack));
        }

        assert(stack_empty(stack));
}

static inline
enum bt_ctf_notif_iter_status notif_iter_status_from_m_status(
                enum bt_ctf_notif_iter_medium_status m_status)
{
        return (int) m_status;
}

static inline
size_t buf_size_bits(struct bt_ctf_notif_iter *notit)
{
        return notit->buf.sz * 8;
}

static inline
size_t buf_available_bits(struct bt_ctf_notif_iter *notit)
{
        return buf_size_bits(notit) - notit->buf.at;
}

static inline
size_t packet_at(struct bt_ctf_notif_iter *notit)
{
        return notit->buf.packet_offset + notit->buf.at;
}

static inline
void buf_consume_bits(struct bt_ctf_notif_iter *notit, size_t incr)
{
        BT_LOGV("Advancing cursor: notit-addr=%p, cur-before=%zu, cur-after=%zu",
                notit, notit->buf.at, notit->buf.at + incr);
        notit->buf.at += incr;
}

static
enum bt_ctf_notif_iter_status request_medium_bytes(
                struct bt_ctf_notif_iter *notit)
{
        uint8_t *buffer_addr = NULL;
        size_t buffer_sz = 0;
        enum bt_ctf_notif_iter_medium_status m_status;

        BT_LOGV("Calling user function (request bytes): notit-addr=%p, "
                "request-size=%zu", notit, notit->medium.max_request_sz);
        m_status = notit->medium.medops.request_bytes(
                notit->medium.max_request_sz, &buffer_addr,
                &buffer_sz, notit->medium.data);
        BT_LOGV("User function returned: status=%s, buf-addr=%p, buf-size=%zu",
                bt_ctf_notif_iter_medium_status_string(m_status),
                buffer_addr, buffer_sz);
        if (m_status == BT_CTF_NOTIF_ITER_MEDIUM_STATUS_OK) {
                assert(buffer_sz != 0);

                /* New packet offset is old one + old size (in bits) */
                notit->buf.packet_offset += buf_size_bits(notit);

                /* Restart at the beginning of the new medium buffer */
                notit->buf.at = 0;
                notit->buf.last_eh_at = SIZE_MAX;

                /* New medium buffer size */
                notit->buf.sz = buffer_sz;

                /* New medium buffer address */
                notit->buf.addr = buffer_addr;

                BT_LOGV("User function returned new bytes: "
                        "packet-offset=%zu, cur=%zu, size=%zu, addr=%p",
                        notit->buf.packet_offset, notit->buf.at,
                        notit->buf.sz, notit->buf.addr);
                BT_LOGV_MEM(buffer_addr, buffer_sz, "Returned bytes at %p:",
                        buffer_addr);
        } else if (m_status == BT_CTF_NOTIF_ITER_MEDIUM_STATUS_EOF) {
                struct bt_ctf_field_type *eh_ft = NULL;
                struct bt_ctf_field_type *sec_ft = NULL;
                struct bt_ctf_field_type *ec_ft = NULL;

                /*
                 * User returned end of stream: validate that we're not
                 * in the middle of a packet header, packet context, or
                 * event.
                 */
                if (notit->state == STATE_DSCOPE_TRACE_PACKET_HEADER_BEGIN) {
                        /* Beginning of packet: always valid */
                        goto good_state;
                }

                if (!notit->meta.stream_class) {
                        goto bad_state;
                }

                eh_ft = bt_ctf_stream_class_get_event_header_type(
                        notit->meta.stream_class);
                sec_ft = bt_ctf_stream_class_get_event_context_type(
                        notit->meta.stream_class);

                if (notit->state == STATE_DSCOPE_STREAM_EVENT_HEADER_BEGIN) {
                        /*
                         * Beginning of event's header is only valid if
                         * the packet is not supposed to have a specific
                         * size (whole packet sequence has in fact only
                         * one packet).
                         */
                        if (notit->cur_packet_size == -1) {
                                goto good_state;
                        }
                }

                if (notit->state == STATE_DSCOPE_STREAM_EVENT_CONTEXT_BEGIN) {
                        /*
                         * Beginning of event's stream event context is
                         * only valid if the packet is not supposed to
                         * have a specific size (whole packet sequence
                         * has in fact only one packet), and there's no
                         * event header.
                         */
                        if (notit->cur_packet_size == -1 && !eh_ft) {
                                goto good_state;
                        }
                }

                if (!notit->meta.event_class) {
                        goto bad_state;
                }

                ec_ft = bt_ctf_event_class_get_context_type(
                        notit->meta.event_class);

                if (notit->state == STATE_DSCOPE_EVENT_CONTEXT_BEGIN) {
                        /*
                         * Beginning of event's context is only valid if
                         * the packet is not supposed to have a specific
                         * size (whole packet sequence has in fact only
                         * one packet), and there's no event header and
                         * no stream event context.
                         */
                        if (notit->cur_packet_size == -1 && !eh_ft && !sec_ft) {
                                goto good_state;
                        }
                }

                if (notit->state == STATE_DSCOPE_EVENT_PAYLOAD_BEGIN) {
                        /*
                         * Beginning of event's context is only valid if
                         * the packet is not supposed to have a specific
                         * size (whole packet sequence has in fact only
                         * one packet), and there's no event header, no
                         * stream event context, and no event context.
                         */
                        if (notit->cur_packet_size == -1 && !eh_ft && !sec_ft &&
                                        !ec_ft) {
                                goto good_state;
                        }
                }

bad_state:
                /* All other states are invalid */
                BT_LOGW("User function returned %s, but notification iterator is in an unexpected state: "
                        "state=%s",
                        bt_ctf_notif_iter_medium_status_string(m_status),
                        state_string(notit->state));
                m_status = BT_CTF_NOTIF_ITER_MEDIUM_STATUS_ERROR;

good_state:
                bt_put(eh_ft);
                bt_put(sec_ft);
                bt_put(ec_ft);
        } else if (m_status < 0) {
                BT_LOGW("User function failed: status=%s",
                        bt_ctf_notif_iter_medium_status_string(m_status));
        }

        return notif_iter_status_from_m_status(m_status);
}

static inline
enum bt_ctf_notif_iter_status buf_ensure_available_bits(
                struct bt_ctf_notif_iter *notit)
{
        enum bt_ctf_notif_iter_status status = BT_CTF_NOTIF_ITER_STATUS_OK;

        if (buf_available_bits(notit) == 0) {
                /*
                 * This _cannot_ return BT_CTF_NOTIF_ITER_STATUS_OK
                 * _and_ no bits.
                 */
                status = request_medium_bytes(notit);
        }

        return status;
}

static
enum bt_ctf_notif_iter_status read_dscope_begin_state(
                struct bt_ctf_notif_iter *notit,
                struct bt_ctf_field_type *dscope_field_type,
                enum state done_state, enum state continue_state,
                struct bt_ctf_field **dscope_field)
{
        enum bt_ctf_notif_iter_status status = BT_CTF_NOTIF_ITER_STATUS_OK;
        enum bt_ctf_btr_status btr_status;
        size_t consumed_bits;

        status = buf_ensure_available_bits(notit);
        if (status != BT_CTF_NOTIF_ITER_STATUS_OK) {
                if (status < 0) {
                        BT_LOGW("Cannot ensure that buffer has at least one byte: "
                                "notif-addr=%p, status=%s",
                                notit, bt_ctf_notif_iter_status_string(status));
                } else {
                        BT_LOGV("Cannot ensure that buffer has at least one byte: "
                                "notif-addr=%p, status=%s",
                                notit, bt_ctf_notif_iter_status_string(status));
                }

                goto end;
        }

        bt_put(*dscope_field);
        notit->cur_dscope_field = dscope_field;
        BT_LOGV("Starting BTR: notit-addr=%p, btr-addr=%p, ft-addr=%p",
                notit, notit->btr, dscope_field_type);
        consumed_bits = bt_ctf_btr_start(notit->btr, dscope_field_type,
                notit->buf.addr, notit->buf.at, packet_at(notit),
                notit->buf.sz, &btr_status);
        BT_LOGV("BTR consumed bits: size=%zu", consumed_bits);

        switch (btr_status) {
        case BT_CTF_BTR_STATUS_OK:
                /* type was read completely */
                BT_LOGV_STR("Field was completely decoded.");
                notit->state = done_state;
                break;
        case BT_CTF_BTR_STATUS_EOF:
                BT_LOGV_STR("BTR needs more data to decode field completely.");
                notit->state = continue_state;
                break;
        default:
                BT_LOGW("BTR failed to start: notit-addr=%p, btr-addr=%p, "
                        "status=%s", notit, notit->btr,
                        bt_ctf_btr_status_string(btr_status));
                status = BT_CTF_NOTIF_ITER_STATUS_ERROR;
                goto end;
        }

        /* Consume bits now since we know we're not in an error state */
        buf_consume_bits(notit, consumed_bits);

end:
        return status;
}

static
enum bt_ctf_notif_iter_status read_dscope_continue_state(
                struct bt_ctf_notif_iter *notit, enum state done_state)
{
        enum bt_ctf_notif_iter_status status = BT_CTF_NOTIF_ITER_STATUS_OK;
        enum bt_ctf_btr_status btr_status;
        size_t consumed_bits;

        status = buf_ensure_available_bits(notit);
        if (status != BT_CTF_NOTIF_ITER_STATUS_OK) {
                if (status < 0) {
                        BT_LOGW("Cannot ensure that buffer has at least one byte: "
                                "notif-addr=%p, status=%s",
                                notit, bt_ctf_notif_iter_status_string(status));
                } else {
                        BT_LOGV("Cannot ensure that buffer has at least one byte: "
                                "notif-addr=%p, status=%s",
                                notit, bt_ctf_notif_iter_status_string(status));
                }

                goto end;
        }

        BT_LOGV("Continuing BTR: notit-addr=%p, btr-addr=%p",
                notit, notit->btr);
        consumed_bits = bt_ctf_btr_continue(notit->btr, notit->buf.addr,
                notit->buf.sz, &btr_status);
        BT_LOGV("BTR consumed bits: size=%zu", consumed_bits);

        switch (btr_status) {
        case BT_CTF_BTR_STATUS_OK:
                /* Type was read completely. */
                BT_LOGV_STR("Field was completely decoded.");
                notit->state = done_state;
                break;
        case BT_CTF_BTR_STATUS_EOF:
                /* Stay in this continue state. */
                BT_LOGV_STR("BTR needs more data to decode field completely.");
                break;
        default:
                BT_LOGW("BTR failed to continue: notit-addr=%p, btr-addr=%p, "
                        "status=%s", notit, notit->btr,
                        bt_ctf_btr_status_string(btr_status));
                status = BT_CTF_NOTIF_ITER_STATUS_ERROR;
                goto end;
        }

        /* Consume bits now since we know we're not in an error state. */
        buf_consume_bits(notit, consumed_bits);
end:
        return status;
}

static
void put_event_dscopes(struct bt_ctf_notif_iter *notit)
{
        BT_LOGV_STR("Putting event header field.");
        BT_PUT(notit->dscopes.stream_event_header);
        BT_LOGV_STR("Putting stream event context field.");
        BT_PUT(notit->dscopes.stream_event_context);
        BT_LOGV_STR("Putting event context field.");
        BT_PUT(notit->dscopes.event_context);
        BT_LOGV_STR("Putting event payload field.");
        BT_PUT(notit->dscopes.event_payload);
}

static
void put_all_dscopes(struct bt_ctf_notif_iter *notit)
{
        BT_LOGV_STR("Putting packet header field.");
        BT_PUT(notit->dscopes.trace_packet_header);
        BT_LOGV_STR("Putting packet context field.");
        BT_PUT(notit->dscopes.stream_packet_context);
        put_event_dscopes(notit);
}

static
enum bt_ctf_notif_iter_status read_packet_header_begin_state(
                struct bt_ctf_notif_iter *notit)
{
        struct bt_ctf_field_type *packet_header_type = NULL;
        enum bt_ctf_notif_iter_status ret = BT_CTF_NOTIF_ITER_STATUS_OK;

        if (bt_ctf_notif_iter_switch_packet(notit)) {
                BT_LOGW("Cannot switch packet: notit-addr=%p", notit);
                ret = BT_CTF_NOTIF_ITER_STATUS_ERROR;
                goto end;
        }

        /* Packet header type is common to the whole trace. */
        packet_header_type = bt_ctf_trace_get_packet_header_type(
                        notit->meta.trace);
        if (!packet_header_type) {
                notit->state = STATE_AFTER_TRACE_PACKET_HEADER;
                goto end;
        }

        BT_LOGV("Decoding packet header field:"
                "notit-addr=%p, trace-addr=%p, trace-name=\"%s\", ft-addr=%p",
                notit, notit->meta.trace,
                bt_ctf_trace_get_name(notit->meta.trace), packet_header_type);
        ret = read_dscope_begin_state(notit, packet_header_type,
                STATE_AFTER_TRACE_PACKET_HEADER,
                STATE_DSCOPE_TRACE_PACKET_HEADER_CONTINUE,
                &notit->dscopes.trace_packet_header);
        if (ret < 0) {
                BT_LOGW("Cannot decode packet header field: "
                        "notit-addr=%p, trace-addr=%p, "
                        "trace-name=\"%s\", ft-addr=%p",
                        notit, notit->meta.trace,
                        bt_ctf_trace_get_name(notit->meta.trace),
                        packet_header_type);
        }
end:
        BT_PUT(packet_header_type);
        return ret;
}

static
enum bt_ctf_notif_iter_status read_packet_header_continue_state(
                struct bt_ctf_notif_iter *notit)
{
        return read_dscope_continue_state(notit,
                        STATE_AFTER_TRACE_PACKET_HEADER);
}

static inline
bool is_struct_type(struct bt_ctf_field_type *field_type)
{
        return bt_ctf_field_type_get_type_id(field_type) ==
                        BT_CTF_FIELD_TYPE_ID_STRUCT;
}

static inline
bool is_variant_type(struct bt_ctf_field_type *field_type)
{
        return bt_ctf_field_type_get_type_id(field_type) ==
                        BT_CTF_FIELD_TYPE_ID_VARIANT;
}

static
struct stream_class_field_path_cache *
create_stream_class_field_path_cache_entry(
                struct bt_ctf_notif_iter *notit,
                struct bt_ctf_stream_class *stream_class)
{
        int v = -1;
        int id = -1;
        int timestamp_end = -1;
        int packet_size = -1;
        int content_size = -1;
        struct stream_class_field_path_cache *cache_entry = g_new0(
                        struct stream_class_field_path_cache, 1);
        struct bt_ctf_field_type *event_header = NULL, *packet_context = NULL;

        if (!cache_entry) {
                BT_LOGE_STR("Failed to allocate one stream class field path cache.");
                goto end;
        }

        event_header = bt_ctf_stream_class_get_event_header_type(stream_class);
        if (event_header && bt_ctf_field_type_is_structure(event_header)) {
                int i, count;

                count = bt_ctf_field_type_structure_get_field_count(
                        event_header);
                assert(count >= 0);

                for (i = 0; i < count; i++) {
                        int ret;
                        const char *name;

                        ret = bt_ctf_field_type_structure_get_field(
                                        event_header, &name, NULL, i);
                        if (ret) {
                                BT_LOGE("Cannot get event header structure field type's field: "
                                        "notit-addr=%p, stream-class-addr=%p, "
                                        "stream-class-name=\"%s\", "
                                        "stream-class-id=%" PRId64 ", "
                                        "ft-addr=%p, index=%d",
                                        notit, stream_class,
                                        bt_ctf_stream_class_get_name(stream_class),
                                        bt_ctf_stream_class_get_id(stream_class),
                                        event_header, i);
                                goto error;
                        }

                        if (v != -1 && id != -1) {
                                break;
                        }

                        if (v == -1 && strcmp(name, "v") == 0) {
                                v = i;
                        } else if (id == -1 && !strcmp(name, "id")) {
                                id = i;
                        }
                }
        }

        packet_context = bt_ctf_stream_class_get_packet_context_type(
                        stream_class);
        if (packet_context && bt_ctf_field_type_is_structure(packet_context)) {
                int i, count;

                count = bt_ctf_field_type_structure_get_field_count(
                        packet_context);
                assert(count >= 0);

                for (i = 0; i < count; i++) {
                        int ret;
                        const char *name;
                        struct bt_ctf_field_type *field_type;

                        if (timestamp_end != -1 && packet_size != -1 &&
                                        content_size != -1) {
                                break;
                        }

                        ret = bt_ctf_field_type_structure_get_field(
                                        packet_context, &name, &field_type, i);
                        if (ret) {
                                BT_LOGE("Cannot get packet context structure field type's field: "
                                        "notit-addr=%p, stream-class-addr=%p, "
                                        "stream-class-name=\"%s\", "
                                        "stream-class-id=%" PRId64 ", "
                                        "ft-addr=%p, index=%d",
                                        notit, stream_class,
                                        bt_ctf_stream_class_get_name(stream_class),
                                        bt_ctf_stream_class_get_id(stream_class),
                                        event_header, i);
                                goto error;
                        }

                        if (timestamp_end == -1 &&
                                        strcmp(name, "timestamp_end") == 0) {
                                struct field_cb_override *override = g_new0(
                                                struct field_cb_override, 1);

                                if (!override) {
                                        BT_PUT(field_type);
                                        goto error;
                                }

                                override->func = btr_timestamp_end_cb;
                                override->data = notit;
                                g_hash_table_insert(notit->field_overrides,
                                        bt_get(field_type), override);
                                timestamp_end = i;
                        } else if (packet_size == -1 &&
                                        !strcmp(name, "packet_size")) {
                                packet_size = i;
                        } else if (content_size == -1 &&
                                        !strcmp(name, "content_size")) {
                                content_size = i;
                        }
                        BT_PUT(field_type);
                }
        }

        cache_entry->v = v;
        cache_entry->id = id;
        cache_entry->timestamp_end = timestamp_end;
        cache_entry->packet_size = packet_size;
        cache_entry->content_size = content_size;
end:
        BT_PUT(event_header);
        BT_PUT(packet_context);
        return cache_entry;
error:
        g_free(cache_entry);
        cache_entry = NULL;
        goto end;
}

static
struct stream_class_field_path_cache *get_stream_class_field_path_cache(
                struct bt_ctf_notif_iter *notit,
                struct bt_ctf_stream_class *stream_class)
{
        bool cache_entry_found;
        struct stream_class_field_path_cache *cache_entry;

        cache_entry_found = g_hash_table_lookup_extended(
                        notit->sc_field_path_caches,
                        stream_class, NULL, (gpointer) &cache_entry);
        if (unlikely(!cache_entry_found)) {
                cache_entry = create_stream_class_field_path_cache_entry(notit,
                        stream_class);
                g_hash_table_insert(notit->sc_field_path_caches,
                        bt_get(stream_class), (gpointer) cache_entry);
        }

        return cache_entry;
}

static inline
enum bt_ctf_notif_iter_status set_current_stream_class(
                struct bt_ctf_notif_iter *notit)
{
        enum bt_ctf_notif_iter_status status = BT_CTF_NOTIF_ITER_STATUS_OK;
        struct bt_ctf_field_type *packet_header_type = NULL;
        struct bt_ctf_field_type *stream_id_field_type = NULL;
        struct bt_ctf_stream_class *new_stream_class = NULL;
        uint64_t stream_id;

        /* Clear the current stream class field path cache. */
        notit->cur_sc_field_path_cache = NULL;

        /* Is there any "stream_id" field in the packet header? */
        packet_header_type = bt_ctf_trace_get_packet_header_type(
                notit->meta.trace);
        if (!packet_header_type) {
                /*
                 * No packet header, therefore no `stream_id` field,
                 * therefore only one stream class.
                 */
                goto single_stream_class;
        }

        assert(is_struct_type(packet_header_type));

        // TODO: optimalize!
        stream_id_field_type =
                bt_ctf_field_type_structure_get_field_type_by_name(
                        packet_header_type, "stream_id");
        if (stream_id_field_type) {
                /* Find appropriate stream class using current stream ID */
                int ret;
                struct bt_ctf_field *stream_id_field = NULL;

                assert(notit->dscopes.trace_packet_header);

                // TODO: optimalize!
                stream_id_field = bt_ctf_field_structure_get_field(
                                notit->dscopes.trace_packet_header, "stream_id");
                assert(stream_id_field);
                ret = bt_ctf_field_unsigned_integer_get_value(
                                stream_id_field, &stream_id);
                assert(!ret);
                BT_PUT(stream_id_field);
        } else {
single_stream_class:
                /* Only one stream: pick the first stream class */
                assert(bt_ctf_trace_get_stream_class_count(
                                notit->meta.trace) == 1);
                stream_id = 0;
        }

        BT_LOGV("Found stream class ID to use: notit-addr=%p, "
                "stream-class-id=%" PRIu64 ", "
                "trace-addr=%p, trace-name=\"%s\"",
                notit, stream_id, notit->meta.trace,
                bt_ctf_trace_get_name(notit->meta.trace));

        new_stream_class = bt_ctf_trace_get_stream_class_by_id(
                notit->meta.trace, stream_id);
        if (!new_stream_class) {
                BT_LOGW("No stream class with ID of stream class ID to use in trace: "
                        "notit-addr=%p, stream-class-id=%" PRIu64 ", "
                        "trace-addr=%p, trace-name=\"%s\"",
                        notit, stream_id, notit->meta.trace,
                        bt_ctf_trace_get_name(notit->meta.trace));
                status = BT_CTF_NOTIF_ITER_STATUS_ERROR;
                goto end;
        }

        if (notit->meta.stream_class) {
                if (new_stream_class != notit->meta.stream_class) {
                        BT_LOGW("Two packets refer to two different stream classes within the same packet sequence: "
                                "notit-addr=%p, prev-stream-class-addr=%p, "
                                "prev-stream-class-name=\"%s\", "
                                "prev-stream-class-id=%" PRId64 ", "
                                "next-stream-class-addr=%p, "
                                "next-stream-class-name=\"%s\", "
                                "next-stream-class-id=%" PRId64 ", "
                                "trace-addr=%p, trace-name=\"%s\"",
                                notit, notit->meta.stream_class,
                                bt_ctf_stream_class_get_name(notit->meta.stream_class),
                                bt_ctf_stream_class_get_id(notit->meta.stream_class),
                                new_stream_class,
                                bt_ctf_stream_class_get_name(new_stream_class),
                                bt_ctf_stream_class_get_id(new_stream_class),
                                notit->meta.trace,
                                bt_ctf_trace_get_name(notit->meta.trace));
                        status = BT_CTF_NOTIF_ITER_STATUS_ERROR;
                        goto end;
                }
        } else {
                BT_MOVE(notit->meta.stream_class, new_stream_class);
        }

        BT_LOGV("Set current stream class: "
                "notit-addr=%p, stream-class-addr=%p, "
                "stream-class-name=\"%s\", stream-class-id=%" PRId64,
                notit, notit->meta.stream_class,
                bt_ctf_stream_class_get_name(notit->meta.stream_class),
                bt_ctf_stream_class_get_id(notit->meta.stream_class));

        /*
         * Retrieve (or lazily create) the current stream class field path
         * cache.
         */
        notit->cur_sc_field_path_cache = get_stream_class_field_path_cache(
                notit, notit->meta.stream_class);
        if (!notit->cur_sc_field_path_cache) {
                BT_LOGW("Cannot retrieve stream class field path from cache: "
                        "notit-addr=%p, stream-class-addr=%p, "
                        "stream-class-name=\"%s\", stream-class-id=%" PRId64,
                        notit, notit->meta.stream_class,
                        bt_ctf_stream_class_get_name(notit->meta.stream_class),
                        bt_ctf_stream_class_get_id(notit->meta.stream_class));
                status = BT_CTF_NOTIF_ITER_STATUS_ERROR;
                goto end;
        }
end:
        BT_PUT(packet_header_type);
        BT_PUT(stream_id_field_type);
        bt_put(new_stream_class);
        return status;
}

static
enum bt_ctf_notif_iter_status after_packet_header_state(
                struct bt_ctf_notif_iter *notit)
{
        enum bt_ctf_notif_iter_status status;

        status = set_current_stream_class(notit);
        if (status == BT_CTF_NOTIF_ITER_STATUS_OK) {
                notit->state = STATE_DSCOPE_STREAM_PACKET_CONTEXT_BEGIN;
        }

        return status;
}

static
enum bt_ctf_notif_iter_status read_packet_context_begin_state(
                struct bt_ctf_notif_iter *notit)
{
        enum bt_ctf_notif_iter_status status = BT_CTF_NOTIF_ITER_STATUS_OK;
        struct bt_ctf_field_type *packet_context_type;

        assert(notit->meta.stream_class);
        packet_context_type = bt_ctf_stream_class_get_packet_context_type(
                notit->meta.stream_class);
        if (!packet_context_type) {
                BT_LOGV("No packet packet context field type in stream class: continuing: "
                        "notit-addr=%p, stream-class-addr=%p, "
                        "stream-class-name=\"%s\", stream-class-id=%" PRId64,
                        notit, notit->meta.stream_class,
                        bt_ctf_stream_class_get_name(notit->meta.stream_class),
                        bt_ctf_stream_class_get_id(notit->meta.stream_class));
                notit->state = STATE_AFTER_STREAM_PACKET_CONTEXT;
                goto end;
        }

        BT_LOGV("Decoding packet context field: "
                "notit-addr=%p, stream-class-addr=%p, "
                "stream-class-name=\"%s\", stream-class-id=%" PRId64 ", "
                "ft-addr=%p",
                notit, notit->meta.stream_class,
                bt_ctf_stream_class_get_name(notit->meta.stream_class),
                bt_ctf_stream_class_get_id(notit->meta.stream_class),
                packet_context_type);
        status = read_dscope_begin_state(notit, packet_context_type,
                STATE_AFTER_STREAM_PACKET_CONTEXT,
                STATE_DSCOPE_STREAM_PACKET_CONTEXT_CONTINUE,
                &notit->dscopes.stream_packet_context);
        if (status < 0) {
                BT_LOGW("Cannot decode packet context field: "
                        "notit-addr=%p, stream-class-addr=%p, "
                        "stream-class-name=\"%s\", "
                        "stream-class-id=%" PRId64 ", ft-addr=%p",
                        notit, notit->meta.stream_class,
                        bt_ctf_stream_class_get_name(notit->meta.stream_class),
                        bt_ctf_stream_class_get_id(notit->meta.stream_class),
                        packet_context_type);
        }

end:
        BT_PUT(packet_context_type);
        return status;
}

static
enum bt_ctf_notif_iter_status read_packet_context_continue_state(
                struct bt_ctf_notif_iter *notit)
{
        return read_dscope_continue_state(notit,
                        STATE_AFTER_STREAM_PACKET_CONTEXT);
}

static
enum bt_ctf_notif_iter_status set_current_packet_content_sizes(
                struct bt_ctf_notif_iter *notit)
{
        enum bt_ctf_notif_iter_status status = BT_CTF_NOTIF_ITER_STATUS_OK;
        struct bt_ctf_field *packet_size_field = NULL;
        struct bt_ctf_field *content_size_field = NULL;
        uint64_t content_size = -1ULL, packet_size = -1ULL;

        if (!notit->dscopes.stream_packet_context) {
                goto end;
        }

        packet_size_field = bt_ctf_field_structure_get_field(
                notit->dscopes.stream_packet_context, "packet_size");
        content_size_field = bt_ctf_field_structure_get_field(
                notit->dscopes.stream_packet_context, "content_size");
        if (packet_size_field) {
                int ret = bt_ctf_field_unsigned_integer_get_value(
                        packet_size_field, &packet_size);

                assert(ret == 0);
                if (packet_size == 0) {
                        BT_LOGW("Invalid packet size: packet context field indicates packet size is zero: "
                                "notit-addr=%p, packet-context-field-addr=%p",
                                notit, notit->dscopes.stream_packet_context);
                        status = BT_CTF_NOTIF_ITER_STATUS_ERROR;
                        goto end;
                } else if ((packet_size % 8) != 0) {
                        BT_LOGW("Invalid packet size: packet context field indicates packet size is not a multiple of 8: "
                                "notit-addr=%p, packet-context-field-addr=%p, "
                                "packet-size=%" PRIu64,
                                notit, notit->dscopes.stream_packet_context,
                                packet_size);
                        status = BT_CTF_NOTIF_ITER_STATUS_ERROR;
                        goto end;
                }
        }

        if (content_size_field) {
                int ret = bt_ctf_field_unsigned_integer_get_value(
                        content_size_field, &content_size);

                assert(ret == 0);
        } else {
                content_size = packet_size;
        }

        if (content_size > packet_size) {
                BT_LOGW("Invalid packet or content size: packet context field indicates content size is greater than packet size: "
                        "notit-addr=%p, packet-context-field-addr=%p, "
                        "packet-size=%" PRIu64 ", content-size=%" PRIu64,
                        notit, notit->dscopes.stream_packet_context,
                        packet_size, content_size);
                status = BT_CTF_NOTIF_ITER_STATUS_ERROR;
                goto end;
        }

        if (packet_size != -1ULL) {
                notit->cur_packet_size = packet_size;
        } else {
                /*
                 * Use the content size as packet size indicator if the
                 * packet size field is missing. This means there is no
                 * padding in this stream.
                 */
                notit->cur_packet_size = content_size;
        }
        notit->cur_content_size = content_size;
        BT_LOGV("Set current packet and content sizes: "
                "notit-addr=%p, packet-size=%" PRIu64 ", content-size=%" PRIu64,
                notit, packet_size, content_size);
end:
        BT_PUT(packet_size_field);
        BT_PUT(content_size_field);
        return status;
}

static
enum bt_ctf_notif_iter_status after_packet_context_state(
                struct bt_ctf_notif_iter *notit)
{
        enum bt_ctf_notif_iter_status status;

        status = set_current_packet_content_sizes(notit);
        if (status == BT_CTF_NOTIF_ITER_STATUS_OK) {
                notit->state = STATE_EMIT_NOTIF_NEW_PACKET;
        }

        return status;
}

static
enum bt_ctf_notif_iter_status read_event_header_begin_state(
                struct bt_ctf_notif_iter *notit)
{
        enum bt_ctf_notif_iter_status status = BT_CTF_NOTIF_ITER_STATUS_OK;
        struct bt_ctf_field_type *event_header_type = NULL;

        /* Reset the position of the last event header */
        notit->buf.last_eh_at = notit->buf.at;

        /* Check if we have some content left */
        if (notit->cur_content_size >= 0) {
                if (packet_at(notit) == notit->cur_content_size) {
                        /* No more events! */
                        BT_LOGV("Reached end of packet: notit-addr=%p, "
                                "cur=%zu", notit, packet_at(notit));
                        notit->state = STATE_EMIT_NOTIF_END_OF_PACKET;
                        goto end;
                } else if (packet_at(notit) > notit->cur_content_size) {
                        /* That's not supposed to happen */
                        BT_LOGV("Before decoding event header field: cursor is passed the packet's content: "
                                "notit-addr=%p, content-size=%" PRId64 ", "
                                "cur=%zu", notit, notit->cur_content_size,
                                packet_at(notit));
                        status = BT_CTF_NOTIF_ITER_STATUS_ERROR;
                        goto end;
                }
        }

        event_header_type = bt_ctf_stream_class_get_event_header_type(
                notit->meta.stream_class);
        if (!event_header_type) {
                notit->state = STATE_AFTER_STREAM_EVENT_HEADER;
                goto end;
        }

        put_event_dscopes(notit);
        BT_LOGV("Decoding event header field: "
                "notit-addr=%p, stream-class-addr=%p, "
                "stream-class-name=\"%s\", stream-class-id=%" PRId64 ", "
                "ft-addr=%p",
                notit, notit->meta.stream_class,
                bt_ctf_stream_class_get_name(notit->meta.stream_class),
                bt_ctf_stream_class_get_id(notit->meta.stream_class),
                event_header_type);
        status = read_dscope_begin_state(notit, event_header_type,
                STATE_AFTER_STREAM_EVENT_HEADER,
                STATE_DSCOPE_STREAM_EVENT_HEADER_CONTINUE,
                &notit->dscopes.stream_event_header);
        if (status < 0) {
                BT_LOGW("Cannot decode event header field: "
                        "notit-addr=%p, stream-class-addr=%p, "
                        "stream-class-name=\"%s\", "
                        "stream-class-id=%" PRId64 ", ft-addr=%p",
                        notit, notit->meta.stream_class,
                        bt_ctf_stream_class_get_name(notit->meta.stream_class),
                        bt_ctf_stream_class_get_id(notit->meta.stream_class),
                        event_header_type);
        }
end:
        BT_PUT(event_header_type);

        return status;
}

static
enum bt_ctf_notif_iter_status read_event_header_continue_state(
                struct bt_ctf_notif_iter *notit)
{
        return read_dscope_continue_state(notit,
                STATE_AFTER_STREAM_EVENT_HEADER);
}

static inline
enum bt_ctf_notif_iter_status set_current_event_class(struct bt_ctf_notif_iter *notit)
{
        /*
         * The assert() calls in this function are okay because it is
         * assumed here that all the metadata objects have been
         * validated for CTF correctness before decoding actual streams.
         */

        enum bt_ctf_notif_iter_status status = BT_CTF_NOTIF_ITER_STATUS_OK;
        struct bt_ctf_field_type *event_header_type;
        struct bt_ctf_field_type *id_field_type = NULL;
        struct bt_ctf_field_type *v_field_type = NULL;
        uint64_t event_id = -1ULL;
        int ret;

        event_header_type = bt_ctf_stream_class_get_event_header_type(
                notit->meta.stream_class);
        if (!event_header_type) {
                /*
                 * No event header, therefore no event class ID field,
                 * therefore only one event class.
                 */
                goto single_event_class;
        }

        /* Is there any "id"/"v" field in the event header? */
        assert(is_struct_type(event_header_type));
        id_field_type = bt_ctf_field_type_structure_get_field_type_by_name(
                event_header_type, "id");
        v_field_type = bt_ctf_field_type_structure_get_field_type_by_name(
                event_header_type, "v");
        assert(notit->dscopes.stream_event_header);
        if (v_field_type) {
                /*
                 *  _   _____ _____
                 * | | |_   _|_   _| __   __ _
                 * | |   | |   | || '_ \ / _` |
                 * | |___| |   | || | | | (_| |  S P E C I A L
                 * |_____|_|   |_||_| |_|\__, |  C A S E ™
                 *                       |___/
                 */
                struct bt_ctf_field *v_field = NULL;
                struct bt_ctf_field *v_struct_field = NULL;
                struct bt_ctf_field *v_struct_id_field = NULL;

                // TODO: optimalize!
                v_field = bt_ctf_field_structure_get_field(
                        notit->dscopes.stream_event_header, "v");
                assert(v_field);

                v_struct_field =
                        bt_ctf_field_variant_get_current_field(v_field);
                if (!v_struct_field) {
                        goto end_v_field_type;
                }

                // TODO: optimalize!
                v_struct_id_field =
                        bt_ctf_field_structure_get_field(v_struct_field, "id");
                if (!v_struct_id_field) {
                        goto end_v_field_type;
                }

                if (bt_ctf_field_is_integer(v_struct_id_field)) {
                        ret = bt_ctf_field_unsigned_integer_get_value(
                                v_struct_id_field, &event_id);
                        if (ret) {
                                BT_LOGV("Cannot get value of unsigned integer field (`id`): continuing: "
                                        "notit=%p, field-addr=%p",
                                        notit, v_struct_id_field);
                                event_id = -1ULL;
                        }
                }

end_v_field_type:
                BT_PUT(v_field);
                BT_PUT(v_struct_field);
                BT_PUT(v_struct_id_field);
        }

        if (id_field_type && event_id == -1ULL) {
                /* Check "id" field */
                struct bt_ctf_field *id_field = NULL;
                int ret = 0;

                // TODO: optimalize!
                id_field = bt_ctf_field_structure_get_field(
                        notit->dscopes.stream_event_header, "id");
                if (!id_field) {
                        goto check_event_id;
                }

                if (bt_ctf_field_is_integer(id_field)) {
                        ret = bt_ctf_field_unsigned_integer_get_value(
                                id_field, &event_id);
                } else if (bt_ctf_field_is_enumeration(id_field)) {
                        struct bt_ctf_field *container;

                        container = bt_ctf_field_enumeration_get_container(
                                id_field);
                        assert(container);
                        ret = bt_ctf_field_unsigned_integer_get_value(
                                container, &event_id);
                        BT_PUT(container);
                }

                assert(ret == 0);
                BT_PUT(id_field);
        }

check_event_id:
        if (event_id == -1ULL) {
single_event_class:
                /* Event ID not found: single event? */
                assert(bt_ctf_stream_class_get_event_class_count(
                        notit->meta.stream_class) == 1);
                event_id = 0;
        }

        BT_LOGV("Found event class ID to use: notit-addr=%p, "
                "stream-class-addr=%p, stream-class-name=\"%s\", "
                "stream-class-id=%" PRId64 ", "
                "event-class-id=%" PRIu64,
                notit, notit->meta.stream_class,
                bt_ctf_stream_class_get_name(notit->meta.stream_class),
                bt_ctf_stream_class_get_id(notit->meta.stream_class),
                event_id);
        BT_PUT(notit->meta.event_class);
        notit->meta.event_class = bt_ctf_stream_class_get_event_class_by_id(
                notit->meta.stream_class, event_id);
        if (!notit->meta.event_class) {
                BT_LOGW("No event class with ID of event class ID to use in stream class: "
                        "notit-addr=%p, stream-class-addr=%p, "
                        "stream-class-name=\"%s\", "
                        "stream-class-id=%" PRId64 ", "
                        "event-class-id=%" PRIu64,
                        notit, notit->meta.stream_class,
                        bt_ctf_stream_class_get_name(notit->meta.stream_class),
                        bt_ctf_stream_class_get_id(notit->meta.stream_class),
                        event_id);
                status = BT_CTF_NOTIF_ITER_STATUS_ERROR;
                goto end;
        }

        BT_LOGV("Set current event class: "
                "notit-addr=%p, event-class-addr=%p, "
                "event-class-name=\"%s\", event-class-id=%" PRId64,
                notit, notit->meta.event_class,
                bt_ctf_event_class_get_name(notit->meta.event_class),
                bt_ctf_event_class_get_id(notit->meta.event_class));

end:
        BT_PUT(event_header_type);
        BT_PUT(id_field_type);
        BT_PUT(v_field_type);

        return status;
}

static
enum bt_ctf_notif_iter_status after_event_header_state(
                struct bt_ctf_notif_iter *notit)
{
        enum bt_ctf_notif_iter_status status;

        status = set_current_event_class(notit);
        if (status != BT_CTF_NOTIF_ITER_STATUS_OK) {
                goto end;
        }

        notit->state = STATE_DSCOPE_STREAM_EVENT_CONTEXT_BEGIN;

end:
        return status;
}

static
enum bt_ctf_notif_iter_status read_stream_event_context_begin_state(
                struct bt_ctf_notif_iter *notit)
{
        enum bt_ctf_notif_iter_status status = BT_CTF_NOTIF_ITER_STATUS_OK;
        struct bt_ctf_field_type *stream_event_context_type;

        stream_event_context_type = bt_ctf_stream_class_get_event_context_type(
                notit->meta.stream_class);
        if (!stream_event_context_type) {
                notit->state = STATE_DSCOPE_EVENT_CONTEXT_BEGIN;
                goto end;
        }

        BT_LOGV("Decoding stream event context field: "
                "notit-addr=%p, stream-class-addr=%p, "
                "stream-class-name=\"%s\", stream-class-id=%" PRId64 ", "
                "ft-addr=%p",
                notit, notit->meta.stream_class,
                bt_ctf_stream_class_get_name(notit->meta.stream_class),
                bt_ctf_stream_class_get_id(notit->meta.stream_class),
                stream_event_context_type);
        status = read_dscope_begin_state(notit, stream_event_context_type,
                STATE_DSCOPE_EVENT_CONTEXT_BEGIN,
                STATE_DSCOPE_STREAM_EVENT_CONTEXT_CONTINUE,
                &notit->dscopes.stream_event_context);
        if (status < 0) {
                BT_LOGW("Cannot decode stream event context field: "
                        "notit-addr=%p, stream-class-addr=%p, "
                        "stream-class-name=\"%s\", "
                        "stream-class-id=%" PRId64 ", ft-addr=%p",
                        notit, notit->meta.stream_class,
                        bt_ctf_stream_class_get_name(notit->meta.stream_class),
                        bt_ctf_stream_class_get_id(notit->meta.stream_class),
                        stream_event_context_type);
        }

end:
        BT_PUT(stream_event_context_type);

        return status;
}

static
enum bt_ctf_notif_iter_status read_stream_event_context_continue_state(
                struct bt_ctf_notif_iter *notit)
{
        return read_dscope_continue_state(notit,
                STATE_DSCOPE_EVENT_CONTEXT_BEGIN);
}

static
enum bt_ctf_notif_iter_status read_event_context_begin_state(
                struct bt_ctf_notif_iter *notit)
{
        enum bt_ctf_notif_iter_status status = BT_CTF_NOTIF_ITER_STATUS_OK;
        struct bt_ctf_field_type *event_context_type;

        event_context_type = bt_ctf_event_class_get_context_type(
                notit->meta.event_class);
        if (!event_context_type) {
                notit->state = STATE_DSCOPE_EVENT_PAYLOAD_BEGIN;
                goto end;
        }

        BT_LOGV("Decoding event context field: "
                "notit-addr=%p, event-class-addr=%p, "
                "event-class-name=\"%s\", event-class-id=%" PRId64 ", "
                "ft-addr=%p",
                notit, notit->meta.event_class,
                bt_ctf_event_class_get_name(notit->meta.event_class),
                bt_ctf_event_class_get_id(notit->meta.event_class),
                event_context_type);
        status = read_dscope_begin_state(notit, event_context_type,
                STATE_DSCOPE_EVENT_PAYLOAD_BEGIN,
                STATE_DSCOPE_EVENT_CONTEXT_CONTINUE,
                &notit->dscopes.event_context);
        if (status < 0) {
                BT_LOGW("Cannot decode event context field: "
                        "notit-addr=%p, event-class-addr=%p, "
                        "event-class-name=\"%s\", "
                        "event-class-id=%" PRId64 ", ft-addr=%p",
                        notit, notit->meta.event_class,
                        bt_ctf_event_class_get_name(notit->meta.event_class),
                        bt_ctf_event_class_get_id(notit->meta.event_class),
                        event_context_type);
        }

end:
        BT_PUT(event_context_type);

        return status;
}

static
enum bt_ctf_notif_iter_status read_event_context_continue_state(
                struct bt_ctf_notif_iter *notit)
{
        return read_dscope_continue_state(notit,
                STATE_DSCOPE_EVENT_PAYLOAD_BEGIN);
}

static
enum bt_ctf_notif_iter_status read_event_payload_begin_state(
                struct bt_ctf_notif_iter *notit)
{
        enum bt_ctf_notif_iter_status status = BT_CTF_NOTIF_ITER_STATUS_OK;
        struct bt_ctf_field_type *event_payload_type;

        event_payload_type = bt_ctf_event_class_get_payload_type(
                notit->meta.event_class);
        if (!event_payload_type) {
                notit->state = STATE_EMIT_NOTIF_EVENT;
                goto end;
        }

        BT_LOGV("Decoding event payload field: "
                "notit-addr=%p, event-class-addr=%p, "
                "event-class-name=\"%s\", event-class-id=%" PRId64 ", "
                "ft-addr=%p",
                notit, notit->meta.event_class,
                bt_ctf_event_class_get_name(notit->meta.event_class),
                bt_ctf_event_class_get_id(notit->meta.event_class),
                event_payload_type);
        status = read_dscope_begin_state(notit, event_payload_type,
                STATE_EMIT_NOTIF_EVENT,
                STATE_DSCOPE_EVENT_PAYLOAD_CONTINUE,
                &notit->dscopes.event_payload);
        if (status < 0) {
                BT_LOGW("Cannot decode event payload field: "
                        "notit-addr=%p, event-class-addr=%p, "
                        "event-class-name=\"%s\", "
                        "event-class-id=%" PRId64 ", ft-addr=%p",
                        notit, notit->meta.event_class,
                        bt_ctf_event_class_get_name(notit->meta.event_class),
                        bt_ctf_event_class_get_id(notit->meta.event_class),
                        event_payload_type);
        }

end:
        BT_PUT(event_payload_type);

        return status;
}

static
enum bt_ctf_notif_iter_status read_event_payload_continue_state(
                struct bt_ctf_notif_iter *notit)
{
        return read_dscope_continue_state(notit, STATE_EMIT_NOTIF_EVENT);
}

static
enum bt_ctf_notif_iter_status skip_packet_padding_state(
                struct bt_ctf_notif_iter *notit)
{
        enum bt_ctf_notif_iter_status status = BT_CTF_NOTIF_ITER_STATUS_OK;
        size_t bits_to_skip;

        assert(notit->cur_packet_size > 0);
        bits_to_skip = notit->cur_packet_size - packet_at(notit);
        if (bits_to_skip == 0) {
                notit->state = STATE_DSCOPE_TRACE_PACKET_HEADER_BEGIN;
                goto end;
        } else {
                size_t bits_to_consume;

                BT_LOGV("Trying to skip %zu bits of padding: notit-addr=%p, size=%zu",
                        bits_to_skip, notit, bits_to_skip);
                status = buf_ensure_available_bits(notit);
                if (status != BT_CTF_NOTIF_ITER_STATUS_OK) {
                        goto end;
                }

                bits_to_consume = MIN(buf_available_bits(notit), bits_to_skip);
                BT_LOGV("Skipping %zu bits of padding: notit-addr=%p, size=%zu",
                        bits_to_consume, notit, bits_to_consume);
                buf_consume_bits(notit, bits_to_consume);
                bits_to_skip = notit->cur_packet_size - packet_at(notit);
                if (bits_to_skip == 0) {
                        notit->state = STATE_DSCOPE_TRACE_PACKET_HEADER_BEGIN;
                        goto end;
                }
        }

end:
        return status;
}

static inline
enum bt_ctf_notif_iter_status handle_state(struct bt_ctf_notif_iter *notit)
{
        enum bt_ctf_notif_iter_status status = BT_CTF_NOTIF_ITER_STATUS_OK;
        const enum state state = notit->state;

        BT_LOGV("Handling state: notit-addr=%p, state=%s",
                notit, state_string(state));

        // TODO: optimalize!
        switch (state) {
        case STATE_INIT:
                notit->state = STATE_DSCOPE_TRACE_PACKET_HEADER_BEGIN;
                break;
        case STATE_DSCOPE_TRACE_PACKET_HEADER_BEGIN:
                status = read_packet_header_begin_state(notit);
                break;
        case STATE_DSCOPE_TRACE_PACKET_HEADER_CONTINUE:
                status = read_packet_header_continue_state(notit);
                break;
        case STATE_AFTER_TRACE_PACKET_HEADER:
                status = after_packet_header_state(notit);
                break;
        case STATE_DSCOPE_STREAM_PACKET_CONTEXT_BEGIN:
                status = read_packet_context_begin_state(notit);
                break;
        case STATE_DSCOPE_STREAM_PACKET_CONTEXT_CONTINUE:
                status = read_packet_context_continue_state(notit);
                break;
        case STATE_AFTER_STREAM_PACKET_CONTEXT:
                status = after_packet_context_state(notit);
                break;
        case STATE_EMIT_NOTIF_NEW_PACKET:
                notit->state = STATE_DSCOPE_STREAM_EVENT_HEADER_BEGIN;
                break;
        case STATE_DSCOPE_STREAM_EVENT_HEADER_BEGIN:
                status = read_event_header_begin_state(notit);
                break;
        case STATE_DSCOPE_STREAM_EVENT_HEADER_CONTINUE:
                status = read_event_header_continue_state(notit);
                break;
        case STATE_AFTER_STREAM_EVENT_HEADER:
                status = after_event_header_state(notit);
                break;
        case STATE_DSCOPE_STREAM_EVENT_CONTEXT_BEGIN:
                status = read_stream_event_context_begin_state(notit);
                break;
        case STATE_DSCOPE_STREAM_EVENT_CONTEXT_CONTINUE:
                status = read_stream_event_context_continue_state(notit);
                break;
        case STATE_DSCOPE_EVENT_CONTEXT_BEGIN:
                status = read_event_context_begin_state(notit);
                break;
        case STATE_DSCOPE_EVENT_CONTEXT_CONTINUE:
                status = read_event_context_continue_state(notit);
                break;
        case STATE_DSCOPE_EVENT_PAYLOAD_BEGIN:
                status = read_event_payload_begin_state(notit);
                break;
        case STATE_DSCOPE_EVENT_PAYLOAD_CONTINUE:
                status = read_event_payload_continue_state(notit);
                break;
        case STATE_EMIT_NOTIF_EVENT:
                notit->state = STATE_DSCOPE_STREAM_EVENT_HEADER_BEGIN;
                break;
        case STATE_SKIP_PACKET_PADDING:
                status = skip_packet_padding_state(notit);
                break;
        case STATE_EMIT_NOTIF_END_OF_PACKET:
                notit->state = STATE_SKIP_PACKET_PADDING;
                break;
        default:
                BT_LOGD("Unknown CTF plugin notification iterator state: "
                        "notit-addr=%p, state=%d", notit, notit->state);
                abort();
        }

        BT_LOGV("Handled state: notit-addr=%p, status=%s, "
                "prev-state=%s, cur-state=%s",
                notit, bt_ctf_notif_iter_status_string(status),
                state_string(state), state_string(notit->state));
        return status;
}

/**
 * Resets the internal state of a CTF notification iterator.
 */
static
void bt_ctf_notif_iter_reset(struct bt_ctf_notif_iter *notit)
{
        assert(notit);
        BT_LOGD("Resetting notification iterator: addr=%p", notit);
        stack_clear(notit->stack);
        BT_PUT(notit->meta.stream_class);
        BT_PUT(notit->meta.event_class);
        BT_PUT(notit->packet);
        BT_PUT(notit->stream);
        put_all_dscopes(notit);
        notit->buf.addr = NULL;
        notit->buf.sz = 0;
        notit->buf.at = 0;
        notit->buf.last_eh_at = SIZE_MAX;
        notit->buf.packet_offset = 0;
        notit->state = STATE_INIT;
        notit->cur_content_size = -1;
        notit->cur_packet_size = -1;
}

static
int bt_ctf_notif_iter_switch_packet(struct bt_ctf_notif_iter *notit)
{
        int ret = 0;

        /*
         * We don't put the stream class here because we need to make
         * sure that all the packets processed by the same notification
         * iterator refer to the same stream class (the first one).
         */
        assert(notit);
        BT_LOGV("Switching packet: notit-addr=%p, cur=%zu",
                notit, notit->buf.at);
        stack_clear(notit->stack);
        BT_PUT(notit->meta.event_class);
        BT_PUT(notit->packet);
        BT_PUT(notit->cur_timestamp_end);
        put_all_dscopes(notit);

        /*
         * Adjust current buffer so that addr points to the beginning of the new
         * packet.
         */
        if (notit->buf.addr) {
                size_t consumed_bytes = (size_t) (notit->buf.at / CHAR_BIT);

                /* Packets are assumed to start on a byte frontier. */
                if (notit->buf.at % CHAR_BIT) {
                        BT_LOGW("Cannot switch packet: current position is not a multiple of 8: "
                                "notit-addr=%p, cur=%zu", notit, notit->buf.at);
                        ret = -1;
                        goto end;
                }

                notit->buf.addr += consumed_bytes;
                notit->buf.sz -= consumed_bytes;
                notit->buf.at = 0;
                notit->buf.packet_offset = 0;
                BT_LOGV("Adjusted buffer: addr=%p, size=%zu",
                        notit->buf.addr, notit->buf.sz);
        }

        notit->cur_content_size = -1;
        notit->cur_packet_size = -1;
        notit->cur_sc_field_path_cache = NULL;

end:
        return ret;
}

static
struct bt_ctf_field *get_next_field(struct bt_ctf_notif_iter *notit)
{
        struct bt_ctf_field *next_field = NULL;
        struct bt_ctf_field *base_field;
        struct bt_ctf_field_type *base_type;
        size_t index;

        assert(!stack_empty(notit->stack));
        index = stack_top(notit->stack)->index;
        base_field = stack_top(notit->stack)->base;
        assert(base_field);
        base_type = bt_ctf_field_get_type(base_field);
        assert(base_type);

        switch (bt_ctf_field_type_get_type_id(base_type)) {
        case BT_CTF_FIELD_TYPE_ID_STRUCT:
                next_field = bt_ctf_field_structure_get_field_by_index(
                        base_field, index);
                break;
        case BT_CTF_FIELD_TYPE_ID_ARRAY:
                next_field = bt_ctf_field_array_get_field(base_field, index);
                break;
        case BT_CTF_FIELD_TYPE_ID_SEQUENCE:
                next_field = bt_ctf_field_sequence_get_field(base_field, index);
                break;
        case BT_CTF_FIELD_TYPE_ID_VARIANT:
                next_field = bt_ctf_field_variant_get_current_field(base_field);
                break;
        default:
                BT_LOGF("Unknown base field type ID: "
                        "notit-addr=%p, ft-addr=%p, ft-id=%s",
                        notit, base_type,
                        bt_ctf_field_type_id_string(
                                bt_ctf_field_type_get_type_id(base_type)));
                abort();
        }

        BT_PUT(base_type);
        return next_field;
}

static
void update_clock_state(uint64_t *state,
                struct bt_ctf_field *value_field)
{
        struct bt_ctf_field_type *value_type = NULL;
        uint64_t requested_new_value;
        uint64_t requested_new_value_mask;
        uint64_t cur_value_masked;
        int requested_new_value_size;
        int ret;

        value_type = bt_ctf_field_get_type(value_field);
        assert(value_type);
        assert(bt_ctf_field_type_is_integer(value_type));
        requested_new_value_size =
                        bt_ctf_field_type_integer_get_size(value_type);
        assert(requested_new_value_size > 0);
        ret = bt_ctf_field_unsigned_integer_get_value(value_field,
                        &requested_new_value);
        assert(!ret);

        /*
         * Special case for a 64-bit new value, which is the limit
         * of a clock value as of this version: overwrite the
         * current value directly.
         */
        if (requested_new_value_size == 64) {
                *state = requested_new_value;
                goto end;
        }

        requested_new_value_mask = (1ULL << requested_new_value_size) - 1;
        cur_value_masked = *state & requested_new_value_mask;

        if (requested_new_value < cur_value_masked) {
                /*
                 * It looks like a wrap happened on the number of bits
                 * of the requested new value. Assume that the clock
                 * value wrapped only one time.
                 */
                *state += requested_new_value_mask + 1;
        }

        /* Clear the low bits of the current clock value. */
        *state &= ~requested_new_value_mask;

        /* Set the low bits of the current clock value. */
        *state |= requested_new_value;
end:
        BT_LOGV("Updated clock's value from integer field's value: "
                "value=%" PRIu64, *state);
        bt_put(value_type);
}

static
enum bt_ctf_btr_status update_clock(struct bt_ctf_notif_iter *notit,
                struct bt_ctf_field *int_field)
{
        gboolean clock_class_found;
        uint64_t *clock_state = NULL;
        struct bt_ctf_field_type *int_field_type = NULL;
        enum bt_ctf_btr_status ret = BT_CTF_BTR_STATUS_OK;
        struct bt_ctf_clock_class *clock_class = NULL;

        int_field_type = bt_ctf_field_get_type(int_field);
        assert(int_field_type);
        clock_class = bt_ctf_field_type_integer_get_mapped_clock_class(
                int_field_type);
        if (likely(!clock_class)) {
                goto end;
        }

        clock_class_found = g_hash_table_lookup_extended(notit->clock_states,
                clock_class, NULL, (gpointer) &clock_state);
        if (!clock_class_found) {
                clock_state = g_new0(uint64_t, 1);
                if (!clock_state) {
                        BT_LOGE_STR("Failed to allocate a uint64_t.");
                        ret = BT_CTF_BTR_STATUS_ENOMEM;
                        goto end;
                }

                g_hash_table_insert(notit->clock_states, bt_get(clock_class),
                        clock_state);
        }

        /* Update the clock's state. */
        BT_LOGV("Updating notification iterator's clock's value from integer field: "
                "notit-addr=%p, clock-class-addr=%p, "
                "clock-class-name=\"%s\", value=%" PRIu64,
                notit, clock_class,
                bt_ctf_clock_class_get_name(clock_class), *clock_state);
        update_clock_state(clock_state, int_field);
end:
        bt_put(int_field_type);
        bt_put(clock_class);
        return ret;
}

static
enum bt_ctf_btr_status btr_unsigned_int_common(uint64_t value,
                struct bt_ctf_field_type *type, void *data,
                struct bt_ctf_field **out_int_field)
{
        enum bt_ctf_btr_status status = BT_CTF_BTR_STATUS_OK;
        struct bt_ctf_field *field = NULL;
        struct bt_ctf_field *int_field = NULL;
        struct bt_ctf_notif_iter *notit = data;
        int ret;

        BT_LOGV("Common unsigned integer function called from BTR: "
                "notit-addr=%p, btr-addr=%p, ft-addr=%p, "
                "ft-id=%s, value=%" PRIu64,
                notit, notit->btr, type,
                bt_ctf_field_type_id_string(
                        bt_ctf_field_type_get_type_id(type)),
                value);

        /* Create next field */
        field = get_next_field(notit);
        if (!field) {
                BT_LOGW("Cannot get next field: notit-addr=%p", notit);
                status = BT_CTF_BTR_STATUS_ERROR;
                goto end_no_put;
        }

        switch(bt_ctf_field_type_get_type_id(type)) {
        case BT_CTF_FIELD_TYPE_ID_INTEGER:
                /* Integer field is created field */
                BT_MOVE(int_field, field);
                bt_get(type);
                break;
        case BT_CTF_FIELD_TYPE_ID_ENUM:
                int_field = bt_ctf_field_enumeration_get_container(field);
                assert(int_field);
                type = bt_ctf_field_get_type(int_field);
                assert(type);
                break;
        default:
                BT_LOGF("Unexpected field type ID: "
                        "notit-addr=%p, ft-addr=%p, ft-id=%s",
                        notit, type,
                        bt_ctf_field_type_id_string(
                                bt_ctf_field_type_get_type_id(type)));
                abort();
        }

        assert(int_field);
        ret = bt_ctf_field_unsigned_integer_set_value(int_field, value);
        assert(ret == 0);
        stack_top(notit->stack)->index++;
        *out_int_field = int_field;
        BT_PUT(field);
        BT_PUT(type);

end_no_put:
        return status;
}

static
enum bt_ctf_btr_status btr_timestamp_end_cb(void *value,
                struct bt_ctf_field_type *type, void *data)
{
        enum bt_ctf_btr_status status;
        struct bt_ctf_field *field = NULL;
        struct bt_ctf_notif_iter *notit = data;

        BT_LOGV("`timestamp_end` unsigned integer function called from BTR: "
                "notit-addr=%p, btr-addr=%p, ft-addr=%p, "
                "ft-id=%s",
                notit, notit->btr, type,
                bt_ctf_field_type_id_string(
                        bt_ctf_field_type_get_type_id(type)));
        status = btr_unsigned_int_common(*((uint64_t *) value), type, data,
                        &field);

        /* Set as the current packet's timestamp_end field. */
        BT_MOVE(notit->cur_timestamp_end, field);
        return status;
}

static
enum bt_ctf_btr_status btr_unsigned_int_cb(uint64_t value,
                struct bt_ctf_field_type *type, void *data)
{
        struct bt_ctf_notif_iter *notit = data;
        enum bt_ctf_btr_status status = BT_CTF_BTR_STATUS_OK;
        struct bt_ctf_field *field = NULL;
        struct field_cb_override *override;

        BT_LOGV("Unsigned integer function called from BTR: "
                "notit-addr=%p, btr-addr=%p, ft-addr=%p, "
                "ft-id=%s, value=%" PRIu64,
                notit, notit->btr, type,
                bt_ctf_field_type_id_string(
                        bt_ctf_field_type_get_type_id(type)),
                value);
        override = g_hash_table_lookup(notit->field_overrides, type);
        if (unlikely(override)) {
                /* Override function logs errors */
                status = override->func(&value, type, override->data);
                goto end;
        }

        status = btr_unsigned_int_common(value, type, data, &field);
        if (status != BT_CTF_BTR_STATUS_OK) {
                /* btr_unsigned_int_common() logs errors */
                goto end;
        }

        status = update_clock(notit, field);
        BT_PUT(field);
end:
        return status;
}

static
enum bt_ctf_btr_status btr_signed_int_cb(int64_t value,
                struct bt_ctf_field_type *type, void *data)
{
        enum bt_ctf_btr_status status = BT_CTF_BTR_STATUS_OK;
        struct bt_ctf_field *field = NULL;
        struct bt_ctf_field *int_field = NULL;
        struct bt_ctf_notif_iter *notit = data;
        int ret;

        BT_LOGV("Signed integer function called from BTR: "
                "notit-addr=%p, btr-addr=%p, ft-addr=%p, "
                "ft-id=%s, value=%" PRId64,
                notit, notit->btr, type,
                bt_ctf_field_type_id_string(
                        bt_ctf_field_type_get_type_id(type)),
                value);

        /* create next field */
        field = get_next_field(notit);
        if (!field) {
                BT_LOGW("Cannot get next field: notit-addr=%p", notit);
                status = BT_CTF_BTR_STATUS_ERROR;
                goto end_no_put;
        }

        switch(bt_ctf_field_type_get_type_id(type)) {
        case BT_CTF_FIELD_TYPE_ID_INTEGER:
                /* Integer field is created field */
                BT_MOVE(int_field, field);
                bt_get(type);
                break;
        case BT_CTF_FIELD_TYPE_ID_ENUM:
                int_field = bt_ctf_field_enumeration_get_container(field);
                assert(int_field);
                type = bt_ctf_field_get_type(int_field);
                assert(type);
                break;
        default:
                BT_LOGF("Unexpected field type ID: "
                        "notit-addr=%p, ft-addr=%p, ft-id=%s",
                        notit, type,
                        bt_ctf_field_type_id_string(
                                bt_ctf_field_type_get_type_id(type)));
                abort();
        }

        assert(int_field);
        ret = bt_ctf_field_signed_integer_set_value(int_field, value);
        assert(!ret);
        stack_top(notit->stack)->index++;
        status = update_clock(notit, int_field);
        BT_PUT(field);
        BT_PUT(int_field);
        BT_PUT(type);

end_no_put:
        return status;
}

static
enum bt_ctf_btr_status btr_floating_point_cb(double value,
                struct bt_ctf_field_type *type, void *data)
{
        enum bt_ctf_btr_status status = BT_CTF_BTR_STATUS_OK;
        struct bt_ctf_field *field = NULL;
        struct bt_ctf_notif_iter *notit = data;
        int ret;

        BT_LOGV("Floating point number function called from BTR: "
                "notit-addr=%p, btr-addr=%p, ft-addr=%p, "
                "ft-id=%s, value=%f",
                notit, notit->btr, type,
                bt_ctf_field_type_id_string(
                        bt_ctf_field_type_get_type_id(type)),
                value);

        /* Create next field */
        field = get_next_field(notit);
        if (!field) {
                BT_LOGW("Cannot get next field: notit-addr=%p", notit);
                status = BT_CTF_BTR_STATUS_ERROR;
                goto end;
        }

        ret = bt_ctf_field_floating_point_set_value(field, value);
        assert(!ret);
        stack_top(notit->stack)->index++;

end:
        BT_PUT(field);
        return status;
}

static
enum bt_ctf_btr_status btr_string_begin_cb(
                struct bt_ctf_field_type *type, void *data)
{
        enum bt_ctf_btr_status status = BT_CTF_BTR_STATUS_OK;
        struct bt_ctf_field *field = NULL;
        struct bt_ctf_notif_iter *notit = data;
        int ret;

        BT_LOGV("String (beginning) function called from BTR: "
                "notit-addr=%p, btr-addr=%p, ft-addr=%p, "
                "ft-id=%s",
                notit, notit->btr, type,
                bt_ctf_field_type_id_string(
                        bt_ctf_field_type_get_type_id(type)));

        /* Create next field */
        field = get_next_field(notit);
        if (!field) {
                BT_LOGW("Cannot get next field: notit-addr=%p", notit);
                status = BT_CTF_BTR_STATUS_ERROR;
                goto end;
        }

        /*
         * Push on stack. Not a compound type per se, but we know that only
         * btr_string_cb() may be called between this call and a subsequent
         * call to btr_string_end_cb().
         */
        ret = stack_push(notit->stack, field);
        if (ret) {
                BT_LOGE("Cannot push string field on stack: "
                        "notit-addr=%p, field-addr=%p", notit, field);
                status = BT_CTF_BTR_STATUS_ERROR;
                goto end;
        }

        /*
         * Initialize string field payload to an empty string since in the
         * case of a length 0 string the btr_string_cb won't be called and
         * we will end up with an unset string payload.
         */
        ret = bt_ctf_field_string_set_value(field, "");
        if (ret) {
                BT_LOGE("Cannot initialize string field's value to an empty string: "
                        "notit-addr=%p, field-addr=%p, ret=%d",
                        notit, field, ret);
                status = BT_CTF_BTR_STATUS_ERROR;
                goto end;
        }

end:
        BT_PUT(field);

        return status;
}

static
enum bt_ctf_btr_status btr_string_cb(const char *value,
                size_t len, struct bt_ctf_field_type *type, void *data)
{
        enum bt_ctf_btr_status status = BT_CTF_BTR_STATUS_OK;
        struct bt_ctf_field *field = NULL;
        struct bt_ctf_notif_iter *notit = data;
        int ret;

        BT_LOGV("String (substring) function called from BTR: "
                "notit-addr=%p, btr-addr=%p, ft-addr=%p, "
                "ft-id=%s, string-length=%zu",
                notit, notit->btr, type,
                bt_ctf_field_type_id_string(
                        bt_ctf_field_type_get_type_id(type)),
                len);

        /* Get string field */
        field = stack_top(notit->stack)->base;
        assert(field);

        /* Append current string */
        ret = bt_ctf_field_string_append_len(field, value, len);
        if (ret) {
                BT_LOGE("Cannot append substring to string field's value: "
                        "notit-addr=%p, field-addr=%p, string-length=%zu, "
                        "ret=%d", notit, field, len, ret);
                status = BT_CTF_BTR_STATUS_ERROR;
                goto end;
        }

end:
        return status;
}

static
enum bt_ctf_btr_status btr_string_end_cb(
                struct bt_ctf_field_type *type, void *data)
{
        struct bt_ctf_notif_iter *notit = data;

        BT_LOGV("String (end) function called from BTR: "
                "notit-addr=%p, btr-addr=%p, ft-addr=%p, "
                "ft-id=%s",
                notit, notit->btr, type,
                bt_ctf_field_type_id_string(
                        bt_ctf_field_type_get_type_id(type)));

        /* Pop string field */
        stack_pop(notit->stack);

        /* Go to next field */
        stack_top(notit->stack)->index++;
        return BT_CTF_BTR_STATUS_OK;
}

enum bt_ctf_btr_status btr_compound_begin_cb(
                struct bt_ctf_field_type *type, void *data)
{
        enum bt_ctf_btr_status status = BT_CTF_BTR_STATUS_OK;
        struct bt_ctf_notif_iter *notit = data;
        struct bt_ctf_field *field;
        int ret;

        BT_LOGV("Compound (beginning) function called from BTR: "
                "notit-addr=%p, btr-addr=%p, ft-addr=%p, "
                "ft-id=%s",
                notit, notit->btr, type,
                bt_ctf_field_type_id_string(
                        bt_ctf_field_type_get_type_id(type)));

        /* Create field */
        if (stack_empty(notit->stack)) {
                /* Root: create dynamic scope field */
                *notit->cur_dscope_field = bt_ctf_field_create(type);
                field = *notit->cur_dscope_field;

                /*
                 * Field will be put at the end of this function
                 * (stack_push() will take one reference, but this
                 * reference is lost upon the equivalent stack_pop()
                 * later), so also get it for our context to own it.
                 */
                bt_get(*notit->cur_dscope_field);

                if (!field) {
                        BT_LOGE("Cannot create compound field: "
                                "notit-addr=%p, ft-addr=%p, ft-id=%s",
                                notit, type,
                                bt_ctf_field_type_id_string(
                                        bt_ctf_field_type_get_type_id(type)));
                        status = BT_CTF_BTR_STATUS_ERROR;
                        goto end;
                }
        } else {
                field = get_next_field(notit);
                if (!field) {
                        BT_LOGW("Cannot get next field: notit-addr=%p", notit);
                        status = BT_CTF_BTR_STATUS_ERROR;
                        goto end;
                }
        }

        /* Push field */
        assert(field);
        ret = stack_push(notit->stack, field);
        if (ret) {
                BT_LOGE("Cannot push compound field onto the stack: "
                        "notit-addr=%p, ft-addr=%p, ft-id=%s, ret=%d",
                        notit, type,
                        bt_ctf_field_type_id_string(
                                bt_ctf_field_type_get_type_id(type)),
                        ret);
                status = BT_CTF_BTR_STATUS_ERROR;
                goto end;
        }

end:
        BT_PUT(field);

        return status;
}

enum bt_ctf_btr_status btr_compound_end_cb(
                struct bt_ctf_field_type *type, void *data)
{
        struct bt_ctf_notif_iter *notit = data;

        BT_LOGV("Compound (end) function called from BTR: "
                "notit-addr=%p, btr-addr=%p, ft-addr=%p, "
                "ft-id=%s",
                notit, notit->btr, type,
                bt_ctf_field_type_id_string(
                        bt_ctf_field_type_get_type_id(type)));
        assert(!stack_empty(notit->stack));

        /* Pop stack */
        stack_pop(notit->stack);

        /* If the stack is not empty, increment the base's index */
        if (!stack_empty(notit->stack)) {
                stack_top(notit->stack)->index++;
        }

        return BT_CTF_BTR_STATUS_OK;
}

static
struct bt_ctf_field *resolve_field(struct bt_ctf_notif_iter *notit,
                struct bt_ctf_field_path *path)
{
        struct bt_ctf_field *field = NULL;
        unsigned int i;

        if (BT_LOG_ON_VERBOSE) {
                GString *gstr = bt_ctf_field_path_string(path);

                BT_LOGV("Resolving field path: notit-addr=%p, field-path=\"%s\"",
                        notit, gstr ? gstr->str : NULL);

                if (gstr) {
                        g_string_free(gstr, TRUE);
                }
        }

        switch (bt_ctf_field_path_get_root_scope(path)) {
        case BT_CTF_SCOPE_TRACE_PACKET_HEADER:
                field = notit->dscopes.trace_packet_header;
                break;
        case BT_CTF_SCOPE_STREAM_PACKET_CONTEXT:
                field = notit->dscopes.stream_packet_context;
                break;
        case BT_CTF_SCOPE_STREAM_EVENT_HEADER:
                field = notit->dscopes.stream_event_header;
                break;
        case BT_CTF_SCOPE_STREAM_EVENT_CONTEXT:
                field = notit->dscopes.stream_event_context;
                break;
        case BT_CTF_SCOPE_EVENT_CONTEXT:
                field = notit->dscopes.event_context;
                break;
        case BT_CTF_SCOPE_EVENT_FIELDS:
                field = notit->dscopes.event_payload;
                break;
        default:
                BT_LOGF("Cannot resolve field path: unknown scope: "
                        "notit-addr=%p, root-scope=%s",
                        notit, bt_ctf_scope_string(
                                bt_ctf_field_path_get_root_scope(path)));
                abort();
        }

        if (!field) {
                BT_LOGW("Cannot resolve field path: root field not found: "
                        "notit-addr=%p, root-scope=%s",
                        notit, bt_ctf_scope_string(
                                bt_ctf_field_path_get_root_scope(path)));
                goto end;
        }

        bt_get(field);

        for (i = 0; i < bt_ctf_field_path_get_index_count(path); ++i) {
                struct bt_ctf_field *next_field = NULL;
                struct bt_ctf_field_type *field_type;
                int index = bt_ctf_field_path_get_index(path, i);

                field_type = bt_ctf_field_get_type(field);
                assert(field_type);

                if (is_struct_type(field_type)) {
                        next_field = bt_ctf_field_structure_get_field_by_index(
                                field, index);
                } else if (is_variant_type(field_type)) {
                        next_field =
                                bt_ctf_field_variant_get_current_field(field);
                }

                BT_PUT(field);
                BT_PUT(field_type);

                if (!next_field) {
                        BT_LOGW("Cannot find next field: "
                                "notit-addr=%p, ft-addr=%p, ft-id=%s, index=%d",
                                notit, field_type,
                                bt_ctf_field_type_id_string(
                                        bt_ctf_field_type_get_type_id(field_type)),
                                index);
                        goto end;
                }

                /* Move next field -> field */
                BT_MOVE(field, next_field);
        }

end:
        return field;
}

static
int64_t btr_get_sequence_length_cb(struct bt_ctf_field_type *type, void *data)
{
        int64_t ret = -1;
        int iret;
        struct bt_ctf_field *seq_field;
        struct bt_ctf_field_path *field_path;
        struct bt_ctf_notif_iter *notit = data;
        struct bt_ctf_field *length_field = NULL;
        uint64_t length;

        field_path = bt_ctf_field_type_sequence_get_length_field_path(type);
        assert(field_path);
        length_field = resolve_field(notit, field_path);
        if (!length_field) {
                BT_LOGW("Cannot resolve sequence field type's length field path: "
                        "notit-addr=%p, ft-addr=%p",
                        notit, type);
                goto end;
        }

        iret = bt_ctf_field_unsigned_integer_get_value(length_field, &length);
        if (iret) {
                BT_LOGE("Cannot get value of sequence length field: "
                        "notit-addr=%p, field-addr=%p",
                        notit, length_field);
                goto end;
        }

        seq_field = stack_top(notit->stack)->base;
        iret = bt_ctf_field_sequence_set_length(seq_field, length_field);
        if (iret) {
                BT_LOGE("Cannot set sequence field's length field: "
                        "notit-addr=%p, seq-field-addr=%p, "
                        "length-field-addr=%p, ",
                        notit, seq_field, length_field);
                goto end;
        }

        ret = (int64_t) length;

end:
        BT_PUT(length_field);
        BT_PUT(field_path);

        return ret;
}

static
struct bt_ctf_field_type *btr_get_variant_type_cb(
                struct bt_ctf_field_type *type, void *data)
{
        struct bt_ctf_field_path *path;
        struct bt_ctf_notif_iter *notit = data;
        struct bt_ctf_field *var_field;
        struct bt_ctf_field *tag_field = NULL;
        struct bt_ctf_field *selected_field = NULL;
        struct bt_ctf_field_type *selected_field_type = NULL;

        path = bt_ctf_field_type_variant_get_tag_field_path(type);
        assert(path);
        tag_field = resolve_field(notit, path);
        if (!tag_field) {
                BT_LOGW("Cannot resolve variant field type's tag field path: "
                        "notit-addr=%p, ft-addr=%p",
                        notit, type);
                goto end;
        }

        /*
         * We found the enumeration tag field instance which should be
         * able to select a current field for this variant. This
         * callback function we're in is called _after_
         * compound_begin(), so the current stack top's base field is
         * the variant field in question. We get the selected field here
         * thanks to this tag field (thus creating the selected field),
         * which will also provide us with its type. Then, this field
         * will remain the current selected one until the next callback
         * function call which is used to fill the current selected
         * field.
         */
        var_field = stack_top(notit->stack)->base;
        selected_field = bt_ctf_field_variant_get_field(var_field, tag_field);
        if (!selected_field) {
                BT_LOGW("Cannot get variant field's selection using tag field: "
                        "notit-addr=%p, var-field-addr=%p, tag-field-addr=%p",
                        notit, var_field, tag_field);
                goto end;
        }

        selected_field_type = bt_ctf_field_get_type(selected_field);

end:
        BT_PUT(tag_field);
        BT_PUT(selected_field);
        BT_PUT(path);

        return selected_field_type;
}

static
int set_event_clocks(struct bt_ctf_event *event,
                struct bt_ctf_notif_iter *notit)
{
        int ret;
        GHashTableIter iter;
        struct bt_ctf_clock_class *clock_class;
        uint64_t *clock_state;

        g_hash_table_iter_init(&iter, notit->clock_states);

        while (g_hash_table_iter_next(&iter, (gpointer) &clock_class,
                        (gpointer) &clock_state)) {
                struct bt_ctf_clock_value *clock_value;

                clock_value = bt_ctf_clock_value_create(clock_class,
                        *clock_state);
                if (!clock_value) {
                        BT_LOGE("Cannot create clock value from clock class: "
                                "notit-addr=%p, clock-class-addr=%p, "
                                "clock-class-name=\"%s\"",
                                notit, clock_class,
                                bt_ctf_clock_class_get_name(clock_class));
                        ret = -1;
                        goto end;
                }
                ret = bt_ctf_event_set_clock_value(event, clock_value);
                bt_put(clock_value);
                if (ret) {
                        struct bt_ctf_event_class *event_class =
                                bt_ctf_event_get_class(event);

                        assert(event_class);
                        BT_LOGE("Cannot set event's clock value: "
                                "notit-addr=%p, event-addr=%p, "
                                "event-class-name=\"%s\", "
                                "event-class-id=%" PRId64 ", "
                                "clock-class-addr=%p, "
                                "clock-class-name=\"%s\", "
                                "clock-value-addr=%p",
                                notit, event,
                                bt_ctf_event_class_get_name(event_class),
                                bt_ctf_event_class_get_id(event_class),
                                clock_class,
                                bt_ctf_clock_class_get_name(clock_class),
                                clock_value);
                        bt_put(event_class);
                        goto end;
                }
        }

        ret = 0;
end:
        return ret;
}

static
struct bt_ctf_event *create_event(struct bt_ctf_notif_iter *notit)
{
        int ret;
        struct bt_ctf_event *event;

        BT_LOGV("Creating event for event notification: "
                "notit-addr=%p, event-class-addr=%p, "
                "event-class-name=\"%s\", "
                "event-class-id=%" PRId64,
                notit, notit->meta.event_class,
                bt_ctf_event_class_get_name(notit->meta.event_class),
                bt_ctf_event_class_get_id(notit->meta.event_class));

        /* Create event object. */
        event = bt_ctf_event_create(notit->meta.event_class);
        if (!event) {
                BT_LOGE("Cannot create event: "
                        "notit-addr=%p, event-class-addr=%p, "
                        "event-class-name=\"%s\", "
                        "event-class-id=%" PRId64,
                        notit, notit->meta.event_class,
                        bt_ctf_event_class_get_name(notit->meta.event_class),
                        bt_ctf_event_class_get_id(notit->meta.event_class));
                goto error;
        }

        /* Set header, stream event context, context, and payload fields. */
        ret = bt_ctf_event_set_header(event,
                notit->dscopes.stream_event_header);
        if (ret) {
                BT_LOGE("Cannot set event's header field: "
                        "notit-addr=%p, event-addr=%p, event-class-addr=%p, "
                        "event-class-name=\"%s\", "
                        "event-class-id=%" PRId64 ", field-addr=%p",
                        notit, event, notit->meta.event_class,
                        bt_ctf_event_class_get_name(notit->meta.event_class),
                        bt_ctf_event_class_get_id(notit->meta.event_class),
                        notit->dscopes.stream_event_header);
                goto error;
        }

        ret = bt_ctf_event_set_stream_event_context(event,
                notit->dscopes.stream_event_context);
        if (ret) {
                BT_LOGE("Cannot set event's context field: "
                        "notit-addr=%p, event-addr=%p, event-class-addr=%p, "
                        "event-class-name=\"%s\", "
                        "event-class-id=%" PRId64 ", field-addr=%p",
                        notit, event, notit->meta.event_class,
                        bt_ctf_event_class_get_name(notit->meta.event_class),
                        bt_ctf_event_class_get_id(notit->meta.event_class),
                        notit->dscopes.stream_event_context);
                goto error;
        }

        ret = bt_ctf_event_set_event_context(event,
                notit->dscopes.event_context);
        if (ret) {
                BT_LOGE("Cannot set event's stream event context field: "
                        "notit-addr=%p, event-addr=%p, event-class-addr=%p, "
                        "event-class-name=\"%s\", "
                        "event-class-id=%" PRId64 ", field-addr=%p",
                        notit, event, notit->meta.event_class,
                        bt_ctf_event_class_get_name(notit->meta.event_class),
                        bt_ctf_event_class_get_id(notit->meta.event_class),
                        notit->dscopes.event_context);
                goto error;
        }

        ret = bt_ctf_event_set_event_payload(event,
                notit->dscopes.event_payload);
        if (ret) {
                BT_LOGE("Cannot set event's payload field: "
                        "notit-addr=%p, event-addr=%p, event-class-addr=%p, "
                        "event-class-name=\"%s\", "
                        "event-class-id=%" PRId64 ", field-addr=%p",
                        notit, event, notit->meta.event_class,
                        bt_ctf_event_class_get_name(notit->meta.event_class),
                        bt_ctf_event_class_get_id(notit->meta.event_class),
                        notit->dscopes.event_payload);
                goto error;
        }

        ret = set_event_clocks(event, notit);
        if (ret) {
                BT_LOGE("Cannot set event's clock values: "
                        "notit-addr=%p, event-addr=%p, event-class-addr=%p, "
                        "event-class-name=\"%s\", "
                        "event-class-id=%" PRId64,
                        notit, event, notit->meta.event_class,
                        bt_ctf_event_class_get_name(notit->meta.event_class),
                        bt_ctf_event_class_get_id(notit->meta.event_class));
                goto error;
        }

        /* Associate with current packet. */
        assert(notit->packet);
        ret = bt_ctf_event_set_packet(event, notit->packet);
        if (ret) {
                BT_LOGE("Cannot set event's header field: "
                        "notit-addr=%p, event-addr=%p, event-class-addr=%p, "
                        "event-class-name=\"%s\", "
                        "event-class-id=%" PRId64 ", packet-addr=%p",
                        notit, event, notit->meta.event_class,
                        bt_ctf_event_class_get_name(notit->meta.event_class),
                        bt_ctf_event_class_get_id(notit->meta.event_class),
                        notit->packet);
                goto error;
        }

        goto end;

error:
        BT_PUT(event);

end:
        return event;
}

static
uint64_t get_cur_stream_instance_id(struct bt_ctf_notif_iter *notit)
{
        struct bt_ctf_field *stream_instance_id_field = NULL;
        uint64_t stream_instance_id = -1ULL;
        int ret;

        if (!notit->dscopes.trace_packet_header) {
                goto end;
        }

        stream_instance_id_field = bt_ctf_field_structure_get_field_by_name(
                notit->dscopes.trace_packet_header, "stream_instance_id");
        if (!stream_instance_id_field) {
                goto end;
        }

        ret = bt_ctf_field_unsigned_integer_get_value(stream_instance_id_field,
                &stream_instance_id);
        if (ret) {
                stream_instance_id = -1ULL;
                goto end;
        }

end:
        bt_put(stream_instance_id_field);
        return stream_instance_id;
}

static
int set_stream(struct bt_ctf_notif_iter *notit)
{
        int ret = 0;
        struct bt_ctf_stream *stream = NULL;

        BT_LOGV("Calling user function (get stream): notit-addr=%p, "
                "stream-class-addr=%p, stream-class-name=\"%s\", "
                "stream-class-id=%" PRId64,
                notit, notit->meta.stream_class,
                bt_ctf_stream_class_get_name(notit->meta.stream_class),
                bt_ctf_stream_class_get_id(notit->meta.stream_class));
        stream = bt_get(notit->medium.medops.get_stream(
                notit->meta.stream_class, get_cur_stream_instance_id(notit),
                notit->medium.data));
        BT_LOGV("User function returned: stream-addr=%p", stream);
        if (!stream) {
                BT_LOGW_STR("User function failed to return a stream object for the given stream class.");
                ret = -1;
                goto end;
        }

        if (notit->stream && stream != notit->stream) {
                BT_LOGW("User function returned a different stream than the previous one for the same sequence of packets.");
                ret = -1;
                goto end;
        }

        BT_MOVE(notit->stream, stream);

end:
        bt_put(stream);
        return ret;
}

static
void create_packet(struct bt_ctf_notif_iter *notit)
{
        int ret;
        struct bt_ctf_packet *packet = NULL;

        BT_LOGV("Creating packet for packet notification: "
                "notit-addr=%p", notit);

        /* Ask the user for the stream */
        ret = set_stream(notit);
        if (ret) {
                goto error;
        }

        BT_LOGV("Creating packet from stream: "
                "notit-addr=%p, stream-addr=%p, "
                "stream-class-addr=%p, "
                "stream-class-name=\"%s\", "
                "stream-class-id=%" PRId64,
                notit, notit->stream, notit->meta.stream_class,
                bt_ctf_stream_class_get_name(notit->meta.stream_class),
                bt_ctf_stream_class_get_id(notit->meta.stream_class));

        /* Create packet */
        packet = bt_ctf_packet_create(notit->stream);
        if (!packet) {
                BT_LOGE("Cannot create packet from stream: "
                        "notit-addr=%p, stream-addr=%p, "
                        "stream-class-addr=%p, "
                        "stream-class-name=\"%s\", "
                        "stream-class-id=%" PRId64,
                        notit, notit->stream, notit->meta.stream_class,
                        bt_ctf_stream_class_get_name(notit->meta.stream_class),
                        bt_ctf_stream_class_get_id(notit->meta.stream_class));
                goto error;
        }

        /* Set packet's context and header fields */
        if (notit->dscopes.trace_packet_header) {
                ret = bt_ctf_packet_set_header(packet,
                        notit->dscopes.trace_packet_header);
                if (ret) {
                        BT_LOGE("Cannot set packet's header field: "
                                "notit-addr=%p, packet-addr=%p, "
                                "stream-addr=%p, "
                                "stream-class-addr=%p, "
                                "stream-class-name=\"%s\", "
                                "stream-class-id=%" PRId64 ", "
                                "field-addr=%p",
                                notit, packet, notit->stream, notit->meta.stream_class,
                                bt_ctf_stream_class_get_name(notit->meta.stream_class),
                                bt_ctf_stream_class_get_id(notit->meta.stream_class),
                                notit->dscopes.trace_packet_header);
                        goto error;
                }
        }

        if (notit->dscopes.stream_packet_context) {
                ret = bt_ctf_packet_set_context(packet,
                        notit->dscopes.stream_packet_context);
                if (ret) {
                        BT_LOGE("Cannot set packet's context field: "
                                "notit-addr=%p, packet-addr=%p, "
                                "stream-addr=%p, "
                                "stream-class-addr=%p, "
                                "stream-class-name=\"%s\", "
                                "stream-class-id=%" PRId64 ", "
                                "field-addr=%p",
                                notit, packet, notit->stream, notit->meta.stream_class,
                                bt_ctf_stream_class_get_name(notit->meta.stream_class),
                                bt_ctf_stream_class_get_id(notit->meta.stream_class),
                                notit->dscopes.trace_packet_header);
                        goto error;
                }
        }

        goto end;

error:
        BT_PUT(packet);

end:
        BT_MOVE(notit->packet, packet);
}

static
void notify_new_packet(struct bt_ctf_notif_iter *notit,
                struct bt_notification **notification)
{
        struct bt_notification *ret;

        /* Initialize the iterator's current packet */
        create_packet(notit);
        if (!notit->packet) {
                BT_LOGE("Cannot create packet for packet notification: "
                        "notit-addr=%p", notit);
                return;
        }

        ret = bt_notification_packet_begin_create(notit->packet);
        if (!ret) {
                BT_LOGE("Cannot create packet beginning notification: "
                        "notit-addr=%p, packet-addr=%p",
                        notit, notit->packet);
                return;
        }
        *notification = ret;
}

static
void notify_end_of_packet(struct bt_ctf_notif_iter *notit,
                struct bt_notification **notification)
{
        struct bt_notification *ret;

        if (!notit->packet) {
                return;
        }

        ret = bt_notification_packet_end_create(notit->packet);
        if (!ret) {
                BT_LOGE("Cannot create packet end notification: "
                        "notit-addr=%p, packet-addr=%p",
                        notit, notit->packet);
                return;
        }
        BT_PUT(notit->packet);
        *notification = ret;
}

static
void notify_event(struct bt_ctf_notif_iter *notit,
                struct bt_clock_class_priority_map *cc_prio_map,
                struct bt_notification **notification)
{
        struct bt_ctf_event *event = NULL;
        struct bt_notification *ret = NULL;

        /* Make sure that the event contains at least one bit of data */
        if (notit->buf.at == notit->buf.last_eh_at) {
                BT_LOGE("Cannot create empty event with 0 bits of data: "
                        "notit-addr=%p, packet-cur=%zu",
                        notit, packet_at(notit));
                goto end;
        }

        /* Create event */
        event = create_event(notit);
        if (!event) {
                BT_LOGE("Cannot create event for event notification: "
                        "notit-addr=%p", notit);
                goto end;
        }

        ret = bt_notification_event_create(event, cc_prio_map);
        if (!ret) {
                BT_LOGE("Cannot create event notification: "
                        "notit-addr=%p, event-addr=%p, "
                        "cc-prio-map-addr=%p",
                        notit, event, cc_prio_map);
                goto end;
        }
        *notification = ret;
end:
        BT_PUT(event);
}

static
void init_trace_field_path_cache(struct bt_ctf_trace *trace,
                struct trace_field_path_cache *trace_field_path_cache)
{
        int stream_id = -1;
        int stream_instance_id = -1;
        int i, count;
        struct bt_ctf_field_type *packet_header = NULL;

        packet_header = bt_ctf_trace_get_packet_header_type(trace);
        if (!packet_header) {
                goto end;
        }

        if (!bt_ctf_field_type_is_structure(packet_header)) {
                goto end;
        }

        count = bt_ctf_field_type_structure_get_field_count(packet_header);
        assert(count >= 0);

        for (i = 0; (i < count && (stream_id == -1 || stream_instance_id == -1)); i++) {
                int ret;
                const char *field_name;

                ret = bt_ctf_field_type_structure_get_field(packet_header,
                                &field_name, NULL, i);
                if (ret) {
                        BT_LOGE("Cannot get structure field's field: "
                                "field-addr=%p, index=%d",
                                packet_header, i);
                        goto end;
                }

                if (stream_id == -1 && !strcmp(field_name, "stream_id")) {
                        stream_id = i;
                } else if (stream_instance_id == -1 &&
                                !strcmp(field_name, "stream_instance_id")) {
                        stream_instance_id = i;
                }
        }

end:
        trace_field_path_cache->stream_id = stream_id;
        trace_field_path_cache->stream_instance_id = stream_instance_id;
        BT_PUT(packet_header);
}

BT_HIDDEN
struct bt_ctf_notif_iter *bt_ctf_notif_iter_create(struct bt_ctf_trace *trace,
                size_t max_request_sz,
                struct bt_ctf_notif_iter_medium_ops medops, void *data)
{
        struct bt_ctf_notif_iter *notit = NULL;
        struct bt_ctf_btr_cbs cbs = {
                .types = {
                        .signed_int = btr_signed_int_cb,
                        .unsigned_int = btr_unsigned_int_cb,
                        .floating_point = btr_floating_point_cb,
                        .string_begin = btr_string_begin_cb,
                        .string = btr_string_cb,
                        .string_end = btr_string_end_cb,
                        .compound_begin = btr_compound_begin_cb,
                        .compound_end = btr_compound_end_cb,
                },
                .query = {
                        .get_sequence_length = btr_get_sequence_length_cb,
                        .get_variant_type = btr_get_variant_type_cb,
                },
        };

        assert(trace);
        assert(medops.request_bytes);
        assert(medops.get_stream);
        BT_LOGD("Creating CTF plugin notification iterator: "
                "trace-addr=%p, trace-name=\"%s\", max-request-size=%zu, "
                "data=%p",
                trace, bt_ctf_trace_get_name(trace), max_request_sz, data);
        notit = g_new0(struct bt_ctf_notif_iter, 1);
        if (!notit) {
                BT_LOGE_STR("Failed to allocate one CTF plugin notification iterator.");
                goto end;
        }
        notit->clock_states = g_hash_table_new_full(g_direct_hash,
                g_direct_equal, bt_put, g_free);
        if (!notit->clock_states) {
                BT_LOGE_STR("Failed to allocate a GHashTable.");
                goto error;
        }
        notit->meta.trace = bt_get(trace);
        notit->medium.medops = medops;
        notit->medium.max_request_sz = max_request_sz;
        notit->medium.data = data;
        notit->stack = stack_new(notit);
        if (!notit->stack) {
                BT_LOGE_STR("Failed to create field stack.");
                goto error;
        }

        notit->btr = bt_ctf_btr_create(cbs, notit);
        if (!notit->btr) {
                BT_LOGE_STR("Failed to create binary type reader (BTR).");
                goto error;
        }

        bt_ctf_notif_iter_reset(notit);
        init_trace_field_path_cache(trace, &notit->trace_field_path_cache);
        notit->sc_field_path_caches = g_hash_table_new_full(g_direct_hash,
                g_direct_equal, bt_put, g_free);
        if (!notit->sc_field_path_caches) {
                BT_LOGE_STR("Failed to allocate a GHashTable.");
                goto error;
        }

        notit->field_overrides = g_hash_table_new_full(g_direct_hash,
                g_direct_equal, bt_put, g_free);
        if (!notit->field_overrides) {
                BT_LOGE_STR("Failed to allocate a GHashTable.");
                goto error;
        }

        BT_LOGD("Created CTF plugin notification iterator: "
                "trace-addr=%p, trace-name=\"%s\", max-request-size=%zu, "
                "data=%p, notit-addr=%p",
                trace, bt_ctf_trace_get_name(trace), max_request_sz, data,
                notit);

end:
        return notit;

error:
        bt_ctf_notif_iter_destroy(notit);
        notit = NULL;
        goto end;
}

void bt_ctf_notif_iter_destroy(struct bt_ctf_notif_iter *notit)
{
        BT_PUT(notit->meta.trace);
        BT_PUT(notit->meta.stream_class);
        BT_PUT(notit->meta.event_class);
        BT_PUT(notit->packet);
        BT_PUT(notit->stream);
        BT_PUT(notit->cur_timestamp_end);
        put_all_dscopes(notit);

        BT_LOGD("Destroying CTF plugin notification iterator: addr=%p", notit);

        if (notit->stack) {
                BT_LOGD_STR("Destroying field stack.");
                stack_destroy(notit->stack);
        }

        if (notit->btr) {
                BT_LOGD("Destroying BTR: btr-addr=%p", notit->btr);
                bt_ctf_btr_destroy(notit->btr);
        }

        if (notit->clock_states) {
                g_hash_table_destroy(notit->clock_states);
        }

        if (notit->sc_field_path_caches) {
                g_hash_table_destroy(notit->sc_field_path_caches);
        }

        if (notit->field_overrides) {
                g_hash_table_destroy(notit->field_overrides);
        }

        g_free(notit);
}

enum bt_ctf_notif_iter_status bt_ctf_notif_iter_get_next_notification(
                struct bt_ctf_notif_iter *notit,
                struct bt_clock_class_priority_map *cc_prio_map,
                struct bt_notification **notification)
{
        enum bt_ctf_notif_iter_status status = BT_CTF_NOTIF_ITER_STATUS_OK;

        assert(notit);
        assert(notification);

        BT_LOGV("Getting next notification: notit-addr=%p, cc-prio-map-addr=%p",
                notit, cc_prio_map);

        while (true) {
                status = handle_state(notit);
                if (status == BT_CTF_NOTIF_ITER_STATUS_AGAIN) {
                        BT_LOGV_STR("Medium returned BT_CTF_NOTIF_ITER_STATUS_AGAIN.");
                        goto end;
                }
                if (status != BT_CTF_NOTIF_ITER_STATUS_OK) {
                        if (status == BT_CTF_NOTIF_ITER_STATUS_EOF) {
                                BT_LOGV_STR("Medium returned BT_CTF_NOTIF_ITER_STATUS_EOF.");
                        } else {
                                BT_LOGW("Cannot handle state: "
                                        "notit-addr=%p, state=%s",
                                        notit, state_string(notit->state));
                        }
                        goto end;
                }

                switch (notit->state) {
                case STATE_EMIT_NOTIF_NEW_PACKET:
                        /* notify_new_packet() logs errors */
                        notify_new_packet(notit, notification);
                        if (!*notification) {
                                status = BT_CTF_NOTIF_ITER_STATUS_ERROR;
                        }
                        goto end;
                case STATE_EMIT_NOTIF_EVENT:
                        /* notify_event() logs errors */
                        notify_event(notit, cc_prio_map, notification);
                        if (!*notification) {
                                status = BT_CTF_NOTIF_ITER_STATUS_ERROR;
                        }
                        goto end;
                case STATE_EMIT_NOTIF_END_OF_PACKET:
                        /* Update clock with timestamp_end field. */
                        if (notit->cur_timestamp_end) {
                                enum bt_ctf_btr_status btr_status;
                                struct bt_ctf_field_type *field_type =
                                                bt_ctf_field_get_type(
                                                        notit->cur_timestamp_end);

                                assert(field_type);
                                btr_status = update_clock(notit,
                                        notit->cur_timestamp_end);
                                BT_PUT(field_type);
                                if (btr_status != BT_CTF_BTR_STATUS_OK) {
                                        BT_LOGW("Cannot update stream's clock value: "
                                                "notit-addr=%p", notit);
                                        status = BT_CTF_NOTIF_ITER_STATUS_ERROR;
                                        goto end;
                                }
                        }

                        /* notify_end_of_packet() logs errors */
                        notify_end_of_packet(notit, notification);
                        if (!*notification) {
                                status = BT_CTF_NOTIF_ITER_STATUS_ERROR;
                        }
                        goto end;
                default:
                        /* Non-emitting state: continue */
                        break;
                }
        }

end:
        return status;
}

BT_HIDDEN
enum bt_ctf_notif_iter_status bt_ctf_notif_iter_get_packet_header_context_fields(
                struct bt_ctf_notif_iter *notit,
                struct bt_ctf_field **packet_header_field,
                struct bt_ctf_field **packet_context_field)
{
        enum bt_ctf_notif_iter_status status = BT_CTF_NOTIF_ITER_STATUS_OK;

        assert(notit);

        if (notit->state == STATE_EMIT_NOTIF_NEW_PACKET) {
                /* We're already there */
                goto set_fields;
        }

        while (true) {
                status = handle_state(notit);
                if (status == BT_CTF_NOTIF_ITER_STATUS_AGAIN) {
                        BT_LOGV_STR("Medium returned BT_CTF_NOTIF_ITER_STATUS_AGAIN.");
                        goto end;
                }
                if (status != BT_CTF_NOTIF_ITER_STATUS_OK) {
                        if (status == BT_CTF_NOTIF_ITER_STATUS_EOF) {
                                BT_LOGV_STR("Medium returned BT_CTF_NOTIF_ITER_STATUS_EOF.");
                        } else {
                                BT_LOGW("Cannot handle state: "
                                        "notit-addr=%p, state=%s",
                                        notit, state_string(notit->state));
                        }
                        goto end;
                }

                switch (notit->state) {
                case STATE_EMIT_NOTIF_NEW_PACKET:
                        /*
                         * Packet header and context fields are
                         * potentially decoded (or they don't exist).
                         */
                        goto set_fields;
                case STATE_INIT:
                case STATE_DSCOPE_TRACE_PACKET_HEADER_BEGIN:
                case STATE_DSCOPE_TRACE_PACKET_HEADER_CONTINUE:
                case STATE_AFTER_TRACE_PACKET_HEADER:
                case STATE_DSCOPE_STREAM_PACKET_CONTEXT_BEGIN:
                case STATE_DSCOPE_STREAM_PACKET_CONTEXT_CONTINUE:
                case STATE_AFTER_STREAM_PACKET_CONTEXT:
                        /* Non-emitting state: continue */
                        break;
                default:
                        /*
                         * We should never get past the
                         * STATE_EMIT_NOTIF_NEW_PACKET state.
                         */
                        BT_LOGF("Unexpected state: notit-addr=%p, state=%s",
                                notit, state_string(notit->state));
                        abort();
                }
        }

set_fields:
        if (packet_header_field) {
                *packet_header_field = bt_get(notit->dscopes.trace_packet_header);
        }

        if (packet_context_field) {
                *packet_context_field = bt_get(notit->dscopes.stream_packet_context);
        }

end:
        return status;
}

BT_HIDDEN
void bt_ctf_notif_iter_set_medops_data(struct bt_ctf_notif_iter *notit,
                void *medops_data)
{
        assert(notit);
        notit->medium.data = medops_data;
}