ctf: index: accommodate lttng-crash timestamp quirk

[babeltrace.git] / src / plugins / ctf / fs-src / fs.c

/*
 * fs.c
 *
 * Babeltrace CTF file system Reader Component
 *
 * Copyright 2015-2017 Philippe Proulx <pproulx@efficios.com>
 * Copyright 2016 Jérémie Galarneau <jeremie.galarneau@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_COMP_LOG_SELF_COMP self_comp
#define BT_LOG_OUTPUT_LEVEL log_level
#define BT_LOG_TAG "PLUGIN/SRC.CTF.FS"
#include "logging/comp-logging.h"

#include "common/common.h"
#include <babeltrace2/babeltrace.h>
#include "common/uuid.h"
#include <glib.h>
#include "common/assert.h"
#include <inttypes.h>
#include <stdbool.h>
#include "fs.h"
#include "metadata.h"
#include "data-stream-file.h"
#include "file.h"
#include "../common/metadata/decoder.h"
#include "../common/metadata/ctf-meta-configure-ir-trace.h"
#include "../common/msg-iter/msg-iter.h"
#include "query.h"

struct tracer_info {
        const char *name;
        int64_t major;
        int64_t minor;
        int64_t patch;
};

static
int msg_iter_data_set_current_ds_file(struct ctf_fs_msg_iter_data *msg_iter_data)
{
        struct ctf_fs_ds_file_info *ds_file_info;
        int ret = 0;

        BT_ASSERT(msg_iter_data->ds_file_info_index <
                msg_iter_data->ds_file_group->ds_file_infos->len);
        ds_file_info = g_ptr_array_index(
                msg_iter_data->ds_file_group->ds_file_infos,
                msg_iter_data->ds_file_info_index);

        ctf_fs_ds_file_destroy(msg_iter_data->ds_file);
        msg_iter_data->ds_file = ctf_fs_ds_file_create(
                msg_iter_data->ds_file_group->ctf_fs_trace,
                msg_iter_data->pc_msg_iter,
                msg_iter_data->msg_iter,
                msg_iter_data->ds_file_group->stream,
                ds_file_info->path->str,
                msg_iter_data->log_level);
        if (!msg_iter_data->ds_file) {
                ret = -1;
        }

        return ret;
}

static
void ctf_fs_msg_iter_data_destroy(
                struct ctf_fs_msg_iter_data *msg_iter_data)
{
        if (!msg_iter_data) {
                return;
        }

        ctf_fs_ds_file_destroy(msg_iter_data->ds_file);

        if (msg_iter_data->msg_iter) {
                bt_msg_iter_destroy(msg_iter_data->msg_iter);
        }

        g_free(msg_iter_data);
}

static
void set_msg_iter_emits_stream_beginning_end_messages(
                struct ctf_fs_msg_iter_data *msg_iter_data)
{
        bt_msg_iter_set_emit_stream_beginning_message(
                msg_iter_data->ds_file->msg_iter,
                msg_iter_data->ds_file_info_index == 0);
        bt_msg_iter_set_emit_stream_end_message(
                msg_iter_data->ds_file->msg_iter,
                msg_iter_data->ds_file_info_index ==
                        msg_iter_data->ds_file_group->ds_file_infos->len - 1);
}

static
bt_component_class_message_iterator_next_method_status ctf_fs_iterator_next_one(
                struct ctf_fs_msg_iter_data *msg_iter_data,
                const bt_message **out_msg)
{
        bt_component_class_message_iterator_next_method_status status;

        BT_ASSERT(msg_iter_data->ds_file);

        while (true) {
                bt_message *msg;

                status = ctf_fs_ds_file_next(msg_iter_data->ds_file, &msg);
                switch (status) {
                case BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK:
                        *out_msg = msg;
                        msg = NULL;
                        goto end;
                case BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_END:
                {
                        int ret;

                        if (msg_iter_data->ds_file_info_index ==
                                        msg_iter_data->ds_file_group->ds_file_infos->len - 1) {
                                /* End of all group's stream files */
                                goto end;
                        }

                        msg_iter_data->ds_file_info_index++;
                        bt_msg_iter_reset_for_next_stream_file(
                                msg_iter_data->msg_iter);
                        set_msg_iter_emits_stream_beginning_end_messages(
                                msg_iter_data);

                        /*
                         * Open and start reading the next stream file
                         * within our stream file group.
                         */
                        ret = msg_iter_data_set_current_ds_file(msg_iter_data);
                        if (ret) {
                                status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_ERROR;
                                goto end;
                        }

                        /* Continue the loop to get the next message */
                        break;
                }
                default:
                        goto end;
                }
        }

end:
        return status;
}

BT_HIDDEN
bt_component_class_message_iterator_next_method_status ctf_fs_iterator_next(
                bt_self_message_iterator *iterator,
                bt_message_array_const msgs, uint64_t capacity,
                uint64_t *count)
{
        bt_component_class_message_iterator_next_method_status status =
                BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK;
        struct ctf_fs_msg_iter_data *msg_iter_data =
                bt_self_message_iterator_get_data(iterator);
        uint64_t i = 0;

        while (i < capacity &&
                        status == BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK) {
                status = ctf_fs_iterator_next_one(msg_iter_data, &msgs[i]);
                if (status == BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK) {
                        i++;
                }
        }

        if (i > 0) {
                /*
                 * Even if ctf_fs_iterator_next_one() returned something
                 * else than BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK, we
                 * accumulated message objects in the output
                 * message array, so we need to return
                 * BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK so that they are
                 * transfered to downstream. This other status occurs
                 * again the next time muxer_msg_iter_do_next() is
                 * called, possibly without any accumulated
                 * message, in which case we'll return it.
                 */
                *count = i;
                status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_NEXT_METHOD_STATUS_OK;
        }

        return status;
}

static
int ctf_fs_iterator_reset(struct ctf_fs_msg_iter_data *msg_iter_data)
{
        int ret;

        msg_iter_data->ds_file_info_index = 0;
        ret = msg_iter_data_set_current_ds_file(msg_iter_data);
        if (ret) {
                goto end;
        }

        bt_msg_iter_reset(msg_iter_data->msg_iter);
        set_msg_iter_emits_stream_beginning_end_messages(msg_iter_data);

end:
        return ret;
}

BT_HIDDEN
bt_component_class_message_iterator_seek_beginning_method_status
ctf_fs_iterator_seek_beginning(bt_self_message_iterator *it)
{
        struct ctf_fs_msg_iter_data *msg_iter_data =
                bt_self_message_iterator_get_data(it);
        bt_component_class_message_iterator_seek_beginning_method_status status =
                BT_COMPONENT_CLASS_MESSAGE_ITERATOR_SEEK_BEGINNING_METHOD_STATUS_OK;

        BT_ASSERT(msg_iter_data);
        if (ctf_fs_iterator_reset(msg_iter_data)) {
                status = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_SEEK_BEGINNING_METHOD_STATUS_ERROR;
        }

        return status;
}

BT_HIDDEN
void ctf_fs_iterator_finalize(bt_self_message_iterator *it)
{
        ctf_fs_msg_iter_data_destroy(
                bt_self_message_iterator_get_data(it));
}

BT_HIDDEN
bt_component_class_message_iterator_init_method_status ctf_fs_iterator_init(
                bt_self_message_iterator *self_msg_iter,
                bt_self_component_source *self_comp_src,
                bt_self_component_port_output *self_port)
{
        struct ctf_fs_port_data *port_data;
        struct ctf_fs_msg_iter_data *msg_iter_data = NULL;
        bt_component_class_message_iterator_init_method_status ret =
                BT_COMPONENT_CLASS_MESSAGE_ITERATOR_INIT_METHOD_STATUS_OK;
        bt_logging_level log_level;
        bt_self_component *self_comp;

        port_data = bt_self_component_port_get_data(
                bt_self_component_port_output_as_self_component_port(
                        self_port));
        BT_ASSERT(port_data);
        log_level = port_data->ctf_fs->log_level;
        self_comp = port_data->ctf_fs->self_comp;
        msg_iter_data = g_new0(struct ctf_fs_msg_iter_data, 1);
        if (!msg_iter_data) {
                ret = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_INIT_METHOD_STATUS_MEMORY_ERROR;
                goto error;
        }

        msg_iter_data->log_level = log_level;
        msg_iter_data->self_comp = self_comp;
        msg_iter_data->pc_msg_iter = self_msg_iter;
        msg_iter_data->msg_iter = bt_msg_iter_create(
                port_data->ds_file_group->ctf_fs_trace->metadata->tc,
                bt_common_get_page_size(msg_iter_data->log_level) * 8,
                ctf_fs_ds_file_medops, NULL, msg_iter_data->log_level,
                self_comp);
        if (!msg_iter_data->msg_iter) {
                BT_COMP_LOGE_STR("Cannot create a CTF message iterator.");
                ret = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_INIT_METHOD_STATUS_MEMORY_ERROR;
                goto error;
        }

        msg_iter_data->ds_file_group = port_data->ds_file_group;
        if (ctf_fs_iterator_reset(msg_iter_data)) {
                ret = BT_COMPONENT_CLASS_MESSAGE_ITERATOR_INIT_METHOD_STATUS_ERROR;
                goto error;
        }

        bt_self_message_iterator_set_data(self_msg_iter,
                msg_iter_data);
        if (ret != BT_COMPONENT_CLASS_MESSAGE_ITERATOR_INIT_METHOD_STATUS_OK) {
                goto error;
        }

        msg_iter_data = NULL;
        goto end;

error:
        bt_self_message_iterator_set_data(self_msg_iter, NULL);

end:
        ctf_fs_msg_iter_data_destroy(msg_iter_data);
        return ret;
}

BT_HIDDEN
void ctf_fs_destroy(struct ctf_fs_component *ctf_fs)
{
        if (!ctf_fs) {
                return;
        }

        if (ctf_fs->traces) {
                g_ptr_array_free(ctf_fs->traces, TRUE);
        }

        if (ctf_fs->port_data) {
                g_ptr_array_free(ctf_fs->port_data, TRUE);
        }

        g_free(ctf_fs);
}

static
void port_data_destroy(struct ctf_fs_port_data *port_data)
{
        if (!port_data) {
                return;
        }

        g_free(port_data);
}

static
void port_data_destroy_notifier(void *data) {
        port_data_destroy(data);
}

static
void ctf_fs_trace_destroy(struct ctf_fs_trace *ctf_fs_trace)
{
        if (!ctf_fs_trace) {
                return;
        }

        if (ctf_fs_trace->ds_file_groups) {
                g_ptr_array_free(ctf_fs_trace->ds_file_groups, TRUE);
        }

        BT_TRACE_PUT_REF_AND_RESET(ctf_fs_trace->trace);

        if (ctf_fs_trace->path) {
                g_string_free(ctf_fs_trace->path, TRUE);
        }

        if (ctf_fs_trace->name) {
                g_string_free(ctf_fs_trace->name, TRUE);
        }

        if (ctf_fs_trace->metadata) {
                ctf_fs_metadata_fini(ctf_fs_trace->metadata);
                g_free(ctf_fs_trace->metadata);
        }

        g_free(ctf_fs_trace);
}

static
void ctf_fs_trace_destroy_notifier(void *data)
{
        struct ctf_fs_trace *trace = data;
        ctf_fs_trace_destroy(trace);
}

struct ctf_fs_component *ctf_fs_component_create(bt_logging_level log_level,
                bt_self_component *self_comp)
{
        struct ctf_fs_component *ctf_fs;

        ctf_fs = g_new0(struct ctf_fs_component, 1);
        if (!ctf_fs) {
                goto error;
        }

        ctf_fs->log_level = log_level;
        ctf_fs->self_comp = self_comp;
        ctf_fs->port_data =
                g_ptr_array_new_with_free_func(port_data_destroy_notifier);
        if (!ctf_fs->port_data) {
                goto error;
        }

        ctf_fs->traces =
                g_ptr_array_new_with_free_func(ctf_fs_trace_destroy_notifier);
        if (!ctf_fs->traces) {
                goto error;
        }

        goto end;

error:
        if (ctf_fs) {
                ctf_fs_destroy(ctf_fs);
        }

end:
        return ctf_fs;
}

void ctf_fs_finalize(bt_self_component_source *component)
{
        ctf_fs_destroy(bt_self_component_get_data(
                bt_self_component_source_as_self_component(component)));
}

gchar *ctf_fs_make_port_name(struct ctf_fs_ds_file_group *ds_file_group)
{
        GString *name = g_string_new(NULL);

        /*
         * The unique port name is generated by concatenating unique identifiers
         * for:
         *
         *   - the trace
         *   - the stream class
         *   - the stream
         */

        /* For the trace, use the uuid if present, else the path. */
        if (ds_file_group->ctf_fs_trace->metadata->tc->is_uuid_set) {
                char uuid_str[BT_UUID_STR_LEN + 1];

                bt_uuid_to_str(ds_file_group->ctf_fs_trace->metadata->tc->uuid, uuid_str);
                g_string_assign(name, uuid_str);
        } else {
                g_string_assign(name, ds_file_group->ctf_fs_trace->path->str);
        }

        /*
         * For the stream class, use the id if present.  We can omit this field
         * otherwise, as there will only be a single stream class.
         */
        if (ds_file_group->sc->id != UINT64_C(-1)) {
                g_string_append_printf(name, " | %" PRIu64, ds_file_group->sc->id);
        }

        /* For the stream, use the id if present, else, use the path. */
        if (ds_file_group->stream_id != UINT64_C(-1)) {
                g_string_append_printf(name, " | %" PRIu64, ds_file_group->stream_id);
        } else {
                BT_ASSERT(ds_file_group->ds_file_infos->len == 1);
                struct ctf_fs_ds_file_info *ds_file_info =
                        g_ptr_array_index(ds_file_group->ds_file_infos, 0);
                g_string_append_printf(name, " | %s", ds_file_info->path->str);
        }

        return g_string_free(name, FALSE);
}

static
int create_one_port_for_trace(struct ctf_fs_component *ctf_fs,
                struct ctf_fs_trace *ctf_fs_trace,
                struct ctf_fs_ds_file_group *ds_file_group)
{
        int ret = 0;
        struct ctf_fs_port_data *port_data = NULL;
        gchar *port_name;
        bt_logging_level log_level = ctf_fs->log_level;
        bt_self_component *self_comp = ctf_fs->self_comp;

        port_name = ctf_fs_make_port_name(ds_file_group);
        if (!port_name) {
                goto error;
        }

        BT_COMP_LOGI("Creating one port named `%s`", port_name);

        /* Create output port for this file */
        port_data = g_new0(struct ctf_fs_port_data, 1);
        if (!port_data) {
                goto error;
        }

        port_data->ctf_fs = ctf_fs;
        port_data->ds_file_group = ds_file_group;
        ret = bt_self_component_source_add_output_port(
                ctf_fs->self_comp_src, port_name, port_data, NULL);
        if (ret) {
                goto error;
        }

        g_ptr_array_add(ctf_fs->port_data, port_data);
        port_data = NULL;
        goto end;

error:
        ret = -1;

end:
        g_free(port_name);

        port_data_destroy(port_data);
        return ret;
}

static
int create_ports_for_trace(struct ctf_fs_component *ctf_fs,
                struct ctf_fs_trace *ctf_fs_trace)
{
        int ret = 0;
        size_t i;
        bt_logging_level log_level = ctf_fs_trace->log_level;
        bt_self_component *self_comp = ctf_fs_trace->self_comp;

        /* Create one output port for each stream file group */
        for (i = 0; i < ctf_fs_trace->ds_file_groups->len; i++) {
                struct ctf_fs_ds_file_group *ds_file_group =
                        g_ptr_array_index(ctf_fs_trace->ds_file_groups, i);

                ret = create_one_port_for_trace(ctf_fs, ctf_fs_trace,
                        ds_file_group);
                if (ret) {
                        BT_COMP_LOGE("Cannot create output port.");
                        goto end;
                }
        }

end:
        return ret;
}

static
void ctf_fs_ds_file_info_destroy(struct ctf_fs_ds_file_info *ds_file_info)
{
        if (!ds_file_info) {
                return;
        }

        if (ds_file_info->path) {
                g_string_free(ds_file_info->path, TRUE);
        }

        g_free(ds_file_info);
}

static
struct ctf_fs_ds_file_info *ctf_fs_ds_file_info_create(const char *path,
                int64_t begin_ns)
{
        struct ctf_fs_ds_file_info *ds_file_info;

        ds_file_info = g_new0(struct ctf_fs_ds_file_info, 1);
        if (!ds_file_info) {
                goto end;
        }

        ds_file_info->path = g_string_new(path);
        if (!ds_file_info->path) {
                ctf_fs_ds_file_info_destroy(ds_file_info);
                ds_file_info = NULL;
                goto end;
        }

        ds_file_info->begin_ns = begin_ns;

end:
        return ds_file_info;
}

static
void ctf_fs_ds_file_group_destroy(struct ctf_fs_ds_file_group *ds_file_group)
{
        if (!ds_file_group) {
                return;
        }

        if (ds_file_group->ds_file_infos) {
                g_ptr_array_free(ds_file_group->ds_file_infos, TRUE);
        }

        if (ds_file_group->index) {
                if (ds_file_group->index->entries) {
                        g_ptr_array_free(ds_file_group->index->entries, TRUE);
                }
                g_free(ds_file_group->index);
        }

        bt_stream_put_ref(ds_file_group->stream);
        g_free(ds_file_group);
}

static
struct ctf_fs_ds_file_group *ctf_fs_ds_file_group_create(
                struct ctf_fs_trace *ctf_fs_trace,
                struct ctf_stream_class *sc,
                uint64_t stream_instance_id,
                struct ctf_fs_ds_index *index)
{
        struct ctf_fs_ds_file_group *ds_file_group;

        ds_file_group = g_new0(struct ctf_fs_ds_file_group, 1);
        if (!ds_file_group) {
                goto error;
        }

        ds_file_group->ds_file_infos = g_ptr_array_new_with_free_func(
                (GDestroyNotify) ctf_fs_ds_file_info_destroy);
        if (!ds_file_group->ds_file_infos) {
                goto error;
        }

        ds_file_group->index = index;

        ds_file_group->stream_id = stream_instance_id;
        BT_ASSERT(sc);
        ds_file_group->sc = sc;
        ds_file_group->ctf_fs_trace = ctf_fs_trace;
        goto end;

error:
        ctf_fs_ds_file_group_destroy(ds_file_group);
        ctf_fs_ds_index_destroy(index);
        ds_file_group = NULL;

end:
        return ds_file_group;
}

/* Replace by g_ptr_array_insert when we depend on glib >= 2.40. */
static
void array_insert(GPtrArray *array, gpointer element, size_t pos)
{
        size_t original_array_len = array->len;

        /* Allocate an unused element at the end of the array. */
        g_ptr_array_add(array, NULL);

        /* If we are not inserting at the end, move the elements by one. */
        if (pos < original_array_len) {
                memmove(&(array->pdata[pos + 1]),
                        &(array->pdata[pos]),
                        (original_array_len - pos) * sizeof(gpointer));
        }

        /* Insert the value. */
        array->pdata[pos] = element;
}

/*
 * Insert ds_file_info in ds_file_group's list of ds_file_infos at the right
 * place to keep it sorted.
 */

static
void ds_file_group_insert_ds_file_info_sorted(
                struct ctf_fs_ds_file_group *ds_file_group,
                struct ctf_fs_ds_file_info *ds_file_info)
{
        guint i;

        /* Find the spot where to insert this ds_file_info. */
        for (i = 0; i < ds_file_group->ds_file_infos->len; i++) {
                struct ctf_fs_ds_file_info *other_ds_file_info =
                        g_ptr_array_index(ds_file_group->ds_file_infos, i);

                if (ds_file_info->begin_ns < other_ds_file_info->begin_ns) {
                        break;
                }
        }

        array_insert(ds_file_group->ds_file_infos, ds_file_info, i);
}

static
void ds_file_group_insert_ds_index_entry_sorted(
        struct ctf_fs_ds_file_group *ds_file_group,
        struct ctf_fs_ds_index_entry *entry)
{
        guint i;

        /* Find the spot where to insert this index entry. */
        for (i = 0; i < ds_file_group->index->entries->len; i++) {
                struct ctf_fs_ds_index_entry *other_entry = g_ptr_array_index(
                        ds_file_group->index->entries, i);

                if (entry->timestamp_begin_ns < other_entry->timestamp_begin_ns) {
                        break;
                }
        }

        array_insert(ds_file_group->index->entries, entry, i);
}

static
int add_ds_file_to_ds_file_group(struct ctf_fs_trace *ctf_fs_trace,
                const char *path)
{
        int64_t stream_instance_id = -1;
        int64_t begin_ns = -1;
        struct ctf_fs_ds_file_group *ds_file_group = NULL;
        bool add_group = false;
        int ret;
        size_t i;
        struct ctf_fs_ds_file *ds_file = NULL;
        struct ctf_fs_ds_file_info *ds_file_info = NULL;
        struct ctf_fs_ds_index *index = NULL;
        struct bt_msg_iter *msg_iter = NULL;
        struct ctf_stream_class *sc = NULL;
        struct bt_msg_iter_packet_properties props;
        bt_logging_level log_level = ctf_fs_trace->log_level;
        bt_self_component *self_comp = ctf_fs_trace->self_comp;

        msg_iter = bt_msg_iter_create(ctf_fs_trace->metadata->tc,
                bt_common_get_page_size(log_level) * 8,
                ctf_fs_ds_file_medops, NULL, log_level, self_comp);
        if (!msg_iter) {
                BT_COMP_LOGE_STR("Cannot create a CTF message iterator.");
                goto error;
        }

        ds_file = ctf_fs_ds_file_create(ctf_fs_trace, NULL, msg_iter,
                NULL, path, log_level);
        if (!ds_file) {
                goto error;
        }

        ret = bt_msg_iter_get_packet_properties(ds_file->msg_iter, &props);
        if (ret) {
                BT_COMP_LOGE("Cannot get stream file's first packet's header and context fields (`%s`).",
                        path);
                goto error;
        }

        sc = ctf_trace_class_borrow_stream_class_by_id(ds_file->metadata->tc,
                props.stream_class_id);
        BT_ASSERT(sc);
        stream_instance_id = props.data_stream_id;

        if (props.snapshots.beginning_clock != UINT64_C(-1)) {
                BT_ASSERT(sc->default_clock_class);
                ret = bt_util_clock_cycles_to_ns_from_origin(
                        props.snapshots.beginning_clock,
                        sc->default_clock_class->frequency,
                        sc->default_clock_class->offset_seconds,
                        sc->default_clock_class->offset_cycles, &begin_ns);
                if (ret) {
                        BT_COMP_LOGE("Cannot convert clock cycles to nanoseconds from origin (`%s`).",
                                path);
                        goto error;
                }
        }

        ds_file_info = ctf_fs_ds_file_info_create(path, begin_ns);
        if (!ds_file_info) {
                goto error;
        }

        index = ctf_fs_ds_file_build_index(ds_file, ds_file_info);
        if (!index) {
                BT_COMP_LOGW("Failed to index CTF stream file \'%s\'",
                        ds_file->file->path->str);
        }

        if (begin_ns == -1) {
                /*
                 * No beggining timestamp to sort the stream files
                 * within a stream file group, so consider that this
                 * file must be the only one within its group.
                 */
                stream_instance_id = -1;
        }

        if (stream_instance_id == -1) {
                /*
                 * No stream instance ID or no beginning timestamp:
                 * create a unique stream file group for this stream
                 * file because, even if there's a stream instance ID,
                 * there's no timestamp to order the file within its
                 * group.
                 */
                ds_file_group = ctf_fs_ds_file_group_create(ctf_fs_trace,
                        sc, UINT64_C(-1), index);
                /* Ownership of index is transferred. */
                index = NULL;

                if (!ds_file_group) {
                        goto error;
                }

                ds_file_group_insert_ds_file_info_sorted(ds_file_group, ds_file_info);

                add_group = true;
                goto end;
        }

        BT_ASSERT(stream_instance_id != -1);
        BT_ASSERT(begin_ns != -1);

        /* Find an existing stream file group with this ID */
        for (i = 0; i < ctf_fs_trace->ds_file_groups->len; i++) {
                ds_file_group = g_ptr_array_index(
                        ctf_fs_trace->ds_file_groups, i);

                if (ds_file_group->sc == sc &&
                                ds_file_group->stream_id ==
                                stream_instance_id) {
                        break;
                }

                ds_file_group = NULL;
        }

        if (!ds_file_group) {
                ds_file_group = ctf_fs_ds_file_group_create(ctf_fs_trace,
                        sc, stream_instance_id, index);
                /* Ownership of index is transferred. */
                index = NULL;
                if (!ds_file_group) {
                        goto error;
                }

                add_group = true;
        }

        ds_file_group_insert_ds_file_info_sorted(ds_file_group, ds_file_info);

        goto end;

error:
        ctf_fs_ds_file_group_destroy(ds_file_group);
        ds_file_group = NULL;
        ret = -1;

end:
        if (add_group && ds_file_group) {
                g_ptr_array_add(ctf_fs_trace->ds_file_groups, ds_file_group);
        }

        ctf_fs_ds_file_destroy(ds_file);

        if (msg_iter) {
                bt_msg_iter_destroy(msg_iter);
        }

        ctf_fs_ds_index_destroy(index);
        return ret;
}

static
int create_ds_file_groups(struct ctf_fs_trace *ctf_fs_trace)
{
        int ret = 0;
        const char *basename;
        GError *error = NULL;
        GDir *dir = NULL;
        bt_logging_level log_level = ctf_fs_trace->log_level;
        bt_self_component *self_comp = ctf_fs_trace->self_comp;

        /* Check each file in the path directory, except specific ones */
        dir = g_dir_open(ctf_fs_trace->path->str, 0, &error);
        if (!dir) {
                BT_COMP_LOGE("Cannot open directory `%s`: %s (code %d)",
                        ctf_fs_trace->path->str, error->message,
                        error->code);
                goto error;
        }

        while ((basename = g_dir_read_name(dir))) {
                struct ctf_fs_file *file;

                if (strcmp(basename, CTF_FS_METADATA_FILENAME) == 0) {
                        /* Ignore the metadata stream. */
                        BT_COMP_LOGI("Ignoring metadata file `%s" G_DIR_SEPARATOR_S "%s`",
                                ctf_fs_trace->path->str, basename);
                        continue;
                }

                if (basename[0] == '.') {
                        BT_COMP_LOGI("Ignoring hidden file `%s" G_DIR_SEPARATOR_S "%s`",
                                ctf_fs_trace->path->str, basename);
                        continue;
                }

                /* Create the file. */
                file = ctf_fs_file_create(log_level, self_comp);
                if (!file) {
                        BT_COMP_LOGE("Cannot create stream file object for file `%s" G_DIR_SEPARATOR_S "%s`",
                                ctf_fs_trace->path->str, basename);
                        goto error;
                }

                /* Create full path string. */
                g_string_append_printf(file->path, "%s" G_DIR_SEPARATOR_S "%s",
                                ctf_fs_trace->path->str, basename);
                if (!g_file_test(file->path->str, G_FILE_TEST_IS_REGULAR)) {
                        BT_COMP_LOGI("Ignoring non-regular file `%s`",
                                file->path->str);
                        ctf_fs_file_destroy(file);
                        file = NULL;
                        continue;
                }

                ret = ctf_fs_file_open(file, "rb");
                if (ret) {
                        BT_COMP_LOGE("Cannot open stream file `%s`", file->path->str);
                        goto error;
                }

                if (file->size == 0) {
                        /* Skip empty stream. */
                        BT_COMP_LOGI("Ignoring empty file `%s`", file->path->str);
                        ctf_fs_file_destroy(file);
                        continue;
                }

                ret = add_ds_file_to_ds_file_group(ctf_fs_trace,
                        file->path->str);
                if (ret) {
                        BT_COMP_LOGE("Cannot add stream file `%s` to stream file group",
                                file->path->str);
                        ctf_fs_file_destroy(file);
                        goto error;
                }

                ctf_fs_file_destroy(file);
        }

        goto end;

error:
        ret = -1;

end:
        if (dir) {
                g_dir_close(dir);
                dir = NULL;
        }

        if (error) {
                g_error_free(error);
        }

        return ret;
}

static
int set_trace_name(bt_trace *trace, const char *name_suffix,
                bt_logging_level log_level, bt_self_component *self_comp)
{
        int ret = 0;
        const bt_value *val;
        GString *name;

        name = g_string_new(NULL);
        if (!name) {
                BT_COMP_LOGE_STR("Failed to allocate a GString.");
                ret = -1;
                goto end;
        }

        /*
         * Check if we have a trace environment string value named `hostname`.
         * If so, use it as the trace name's prefix.
         */
        val = bt_trace_borrow_environment_entry_value_by_name_const(
                trace, "hostname");
        if (val && bt_value_is_string(val)) {
                g_string_append(name, bt_value_string_get(val));

                if (name_suffix) {
                        g_string_append_c(name, G_DIR_SEPARATOR);
                }
        }

        if (name_suffix) {
                g_string_append(name, name_suffix);
        }

        ret = bt_trace_set_name(trace, name->str);
        if (ret) {
                goto end;
        }

        goto end;

end:
        if (name) {
                g_string_free(name, TRUE);
        }

        return ret;
}

static
struct ctf_fs_trace *ctf_fs_trace_create(bt_self_component *self_comp,
                const char *path, const char *name,
                struct ctf_fs_metadata_config *metadata_config,
                bt_logging_level log_level)
{
        struct ctf_fs_trace *ctf_fs_trace;
        int ret;

        ctf_fs_trace = g_new0(struct ctf_fs_trace, 1);
        if (!ctf_fs_trace) {
                goto end;
        }

        ctf_fs_trace->log_level = log_level;
        ctf_fs_trace->self_comp = self_comp;
        ctf_fs_trace->path = g_string_new(path);
        if (!ctf_fs_trace->path) {
                goto error;
        }

        ctf_fs_trace->name = g_string_new(name);
        if (!ctf_fs_trace->name) {
                goto error;
        }

        ctf_fs_trace->metadata = g_new0(struct ctf_fs_metadata, 1);
        if (!ctf_fs_trace->metadata) {
                goto error;
        }

        ctf_fs_metadata_init(ctf_fs_trace->metadata);
        ctf_fs_trace->ds_file_groups = g_ptr_array_new_with_free_func(
                (GDestroyNotify) ctf_fs_ds_file_group_destroy);
        if (!ctf_fs_trace->ds_file_groups) {
                goto error;
        }

        ret = ctf_fs_metadata_set_trace_class(self_comp, ctf_fs_trace,
                metadata_config);
        if (ret) {
                goto error;
        }

        if (ctf_fs_trace->metadata->trace_class) {
                ctf_fs_trace->trace =
                        bt_trace_create(ctf_fs_trace->metadata->trace_class);
                if (!ctf_fs_trace->trace) {
                        goto error;
                }
        }

        if (ctf_fs_trace->trace) {
                ret = ctf_trace_class_configure_ir_trace(
                        ctf_fs_trace->metadata->tc, ctf_fs_trace->trace);
                if (ret) {
                        goto error;
                }

                ret = set_trace_name(ctf_fs_trace->trace, name, log_level,
                        self_comp);
                if (ret) {
                        goto error;
                }
        }

        ret = create_ds_file_groups(ctf_fs_trace);
        if (ret) {
                goto error;
        }

        goto end;

error:
        ctf_fs_trace_destroy(ctf_fs_trace);
        ctf_fs_trace = NULL;

end:
        return ctf_fs_trace;
}

static
int path_is_ctf_trace(const char *path)
{
        GString *metadata_path = g_string_new(NULL);
        int ret = 0;

        if (!metadata_path) {
                ret = -1;
                goto end;
        }

        g_string_printf(metadata_path, "%s" G_DIR_SEPARATOR_S "%s", path, CTF_FS_METADATA_FILENAME);

        if (g_file_test(metadata_path->str, G_FILE_TEST_IS_REGULAR)) {
                ret = 1;
                goto end;
        }

end:
        g_string_free(metadata_path, TRUE);
        return ret;
}

static
int add_trace_path(GList **trace_paths, const char *path,
                bt_logging_level log_level, bt_self_component *self_comp)
{
        GString *norm_path = NULL;
        int ret = 0;

        norm_path = bt_common_normalize_path(path, NULL);
        if (!norm_path) {
                BT_COMP_LOGE("Failed to normalize path `%s`.", path);
                ret = -1;
                goto end;
        }

        // FIXME: Remove or ifdef for __MINGW32__
        if (strcmp(norm_path->str, "/") == 0) {
                BT_COMP_LOGE("Opening a trace in `/` is not supported.");
                ret = -1;
                goto end;
        }

        *trace_paths = g_list_prepend(*trace_paths, norm_path);
        BT_ASSERT(*trace_paths);
        norm_path = NULL;

end:
        if (norm_path) {
                g_string_free(norm_path, TRUE);
        }

        return ret;
}

static
int ctf_fs_find_traces(GList **trace_paths, const char *start_path,
                bt_logging_level log_level, bt_self_component *self_comp)
{
        int ret;
        GError *error = NULL;
        GDir *dir = NULL;
        const char *basename = NULL;

        /* Check if the starting path is a CTF trace itself */
        ret = path_is_ctf_trace(start_path);
        if (ret < 0) {
                goto end;
        }

        if (ret) {
                /*
                 * Stop recursion: a CTF trace cannot contain another
                 * CTF trace.
                 */
                ret = add_trace_path(trace_paths, start_path, log_level,
                        self_comp);
                goto end;
        }

        /* Look for subdirectories */
        if (!g_file_test(start_path, G_FILE_TEST_IS_DIR)) {
                /* Starting path is not a directory: end of recursion */
                goto end;
        }

        dir = g_dir_open(start_path, 0, &error);
        if (!dir) {
                if (error->code == G_FILE_ERROR_ACCES) {
                        BT_COMP_LOGI("Cannot open directory `%s`: %s (code %d): continuing",
                                start_path, error->message, error->code);
                        goto end;
                }

                BT_COMP_LOGE("Cannot open directory `%s`: %s (code %d)",
                        start_path, error->message, error->code);
                ret = -1;
                goto end;
        }

        while ((basename = g_dir_read_name(dir))) {
                GString *sub_path = g_string_new(NULL);

                if (!sub_path) {
                        ret = -1;
                        goto end;
                }

                g_string_printf(sub_path, "%s" G_DIR_SEPARATOR_S "%s", start_path, basename);
                ret = ctf_fs_find_traces(trace_paths, sub_path->str,
                        log_level, self_comp);
                g_string_free(sub_path, TRUE);
                if (ret) {
                        goto end;
                }
        }

end:
        if (dir) {
                g_dir_close(dir);
        }

        if (error) {
                g_error_free(error);
        }

        return ret;
}

static
GList *ctf_fs_create_trace_names(GList *trace_paths, const char *base_path) {
        GList *trace_names = NULL;
        GList *node;
        const char *last_sep;
        size_t base_dist;

        /*
         * At this point we know that all the trace paths are
         * normalized, and so is the base path. This means that
         * they are absolute and they don't end with a separator.
         * We can simply find the location of the last separator
         * in the base path, which gives us the name of the actual
         * directory to look into, and use this location as the
         * start of each trace name within each trace path.
         *
         * For example:
         *
         *     Base path: /home/user/my-traces/some-trace
         *     Trace paths:
         *       - /home/user/my-traces/some-trace/host1/trace1
         *       - /home/user/my-traces/some-trace/host1/trace2
         *       - /home/user/my-traces/some-trace/host2/trace
         *       - /home/user/my-traces/some-trace/other-trace
         *
         * In this case the trace names are:
         *
         *       - some-trace/host1/trace1
         *       - some-trace/host1/trace2
         *       - some-trace/host2/trace
         *       - some-trace/other-trace
         */
        last_sep = strrchr(base_path, G_DIR_SEPARATOR);

        /* We know there's at least one separator */
        BT_ASSERT(last_sep);

        /* Distance to base */
        base_dist = last_sep - base_path + 1;

        /* Create the trace names */
        for (node = trace_paths; node; node = g_list_next(node)) {
                GString *trace_name = g_string_new(NULL);
                GString *trace_path = node->data;

                BT_ASSERT(trace_name);
                g_string_assign(trace_name, &trace_path->str[base_dist]);
                trace_names = g_list_append(trace_names, trace_name);
        }

        return trace_names;
}

/* Helper for ctf_fs_component_create_ctf_fs_traces, to handle a single path/root. */

static
int ctf_fs_component_create_ctf_fs_traces_one_root(
                struct ctf_fs_component *ctf_fs,
                const char *path_param)
{
        struct ctf_fs_trace *ctf_fs_trace = NULL;
        int ret = 0;
        GString *norm_path = NULL;
        GList *trace_paths = NULL;
        GList *trace_names = NULL;
        GList *tp_node;
        GList *tn_node;
        bt_logging_level log_level = ctf_fs->log_level;
        bt_self_component *self_comp = ctf_fs->self_comp;

        norm_path = bt_common_normalize_path(path_param, NULL);
        if (!norm_path) {
                BT_COMP_LOGE("Failed to normalize path: `%s`.",
                        path_param);
                goto error;
        }

        ret = ctf_fs_find_traces(&trace_paths, norm_path->str, log_level,
                self_comp);
        if (ret) {
                goto error;
        }

        if (!trace_paths) {
                BT_COMP_LOGE("No CTF traces recursively found in `%s`.",
                        path_param);
                (void) BT_CURRENT_THREAD_ERROR_APPEND_CAUSE_FROM_COMPONENT(
                        ctf_fs->self_comp,
                        "No CTF traces recursively found in `%s`.", path_param);
                goto error;
        }

        trace_names = ctf_fs_create_trace_names(trace_paths, norm_path->str);
        if (!trace_names) {
                BT_COMP_LOGE("Cannot create trace names from trace paths.");
                goto error;
        }

        for (tp_node = trace_paths, tn_node = trace_names; tp_node;
                        tp_node = g_list_next(tp_node),
                        tn_node = g_list_next(tn_node)) {
                GString *trace_path = tp_node->data;
                GString *trace_name = tn_node->data;

                ctf_fs_trace = ctf_fs_trace_create(self_comp,
                                trace_path->str, trace_name->str,
                                &ctf_fs->metadata_config,
                                log_level);
                if (!ctf_fs_trace) {
                        BT_COMP_LOGE("Cannot create trace for `%s`.",
                                trace_path->str);
                        goto error;
                }

                g_ptr_array_add(ctf_fs->traces, ctf_fs_trace);
                ctf_fs_trace = NULL;
        }

        goto end;

error:
        ret = -1;
        ctf_fs_trace_destroy(ctf_fs_trace);

end:
        for (tp_node = trace_paths; tp_node; tp_node = g_list_next(tp_node)) {
                if (tp_node->data) {
                        g_string_free(tp_node->data, TRUE);
                }
        }

        for (tn_node = trace_names; tn_node; tn_node = g_list_next(tn_node)) {
                if (tn_node->data) {
                        g_string_free(tn_node->data, TRUE);
                }
        }

        if (trace_paths) {
                g_list_free(trace_paths);
        }

        if (trace_names) {
                g_list_free(trace_names);
        }

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

        return ret;
}

/* GCompareFunc to sort traces by UUID. */

static
gint sort_traces_by_uuid(gconstpointer a, gconstpointer b)
{
        const struct ctf_fs_trace *trace_a = *((const struct ctf_fs_trace **) a);
        const struct ctf_fs_trace *trace_b = *((const struct ctf_fs_trace **) b);

        bool trace_a_has_uuid = trace_a->metadata->tc->is_uuid_set;
        bool trace_b_has_uuid = trace_b->metadata->tc->is_uuid_set;
        gint ret;

        /* Order traces without uuid first. */
        if (!trace_a_has_uuid && trace_b_has_uuid) {
                ret = -1;
        } else if (trace_a_has_uuid && !trace_b_has_uuid) {
                ret = 1;
        } else if (!trace_a_has_uuid && !trace_b_has_uuid) {
                ret = 0;
        } else {
                ret = bt_uuid_compare(trace_a->metadata->tc->uuid, trace_b->metadata->tc->uuid);
        }

        return ret;
}

/*
 * Count the number of stream and event classes defined by this trace's metadata.
 *
 * This is used to determine which metadata is the "latest", out of multiple
 * traces sharing the same UUID.  It is assumed that amongst all these metadatas,
 * a bigger metadata is a superset of a smaller metadata.  Therefore, it is
 * enough to just count the classes.
 */

static
unsigned int metadata_count_stream_and_event_classes(struct ctf_fs_trace *trace)
{
        unsigned int num = trace->metadata->tc->stream_classes->len;
        guint i;

        for (i = 0; i < trace->metadata->tc->stream_classes->len; i++) {
                struct ctf_stream_class *sc = trace->metadata->tc->stream_classes->pdata[i];
                num += sc->event_classes->len;
        }

        return num;
}

/*
 * Merge the src ds_file_group into dest.  This consists of merging their
 * ds_file_infos, making sure to keep the result sorted.
 */

static
void merge_ctf_fs_ds_file_groups(struct ctf_fs_ds_file_group *dest, struct ctf_fs_ds_file_group *src)
{
        guint i;

        for (i = 0; i < src->ds_file_infos->len; i++) {
                struct ctf_fs_ds_file_info *ds_file_info =
                        g_ptr_array_index(src->ds_file_infos, i);

                /* Ownership of the ds_file_info is transferred to dest. */
                g_ptr_array_index(src->ds_file_infos, i) = NULL;

                ds_file_group_insert_ds_file_info_sorted(dest, ds_file_info);
        }

        /* Merge both indexes. */
        for (i = 0; i < src->index->entries->len; i++) {
                struct ctf_fs_ds_index_entry *entry = g_ptr_array_index(
                        src->index->entries, i);

                /*
                 * Ownership of the ctf_fs_ds_index_entry is transferred to
                 * dest.
                 */
                g_ptr_array_index(src->index->entries, i) = NULL;

                ds_file_group_insert_ds_index_entry_sorted(dest, entry);
        }
}
/* Merge src_trace's data stream file groups into dest_trace's. */

static
int merge_matching_ctf_fs_ds_file_groups(
                struct ctf_fs_trace *dest_trace,
                struct ctf_fs_trace *src_trace)
{

        GPtrArray *dest = dest_trace->ds_file_groups;
        GPtrArray *src = src_trace->ds_file_groups;
        guint s_i;
        int ret = 0;

        /*
         * Save the initial length of dest: we only want to check against the
         * original elements in the inner loop.
         */
        const guint dest_len = dest->len;

        for (s_i = 0; s_i < src->len; s_i++) {
                struct ctf_fs_ds_file_group *src_group = g_ptr_array_index(src, s_i);
                struct ctf_fs_ds_file_group *dest_group = NULL;

                /* A stream instance without ID can't match a stream in the other trace.  */
                if (src_group->stream_id != -1) {
                        guint d_i;

                        /* Let's search for a matching ds_file_group in the destination.  */
                        for (d_i = 0; d_i < dest_len; d_i++) {
                                struct ctf_fs_ds_file_group *candidate_dest = g_ptr_array_index(dest, d_i);

                                /* Can't match a stream instance without ID.  */
                                if (candidate_dest->stream_id == -1) {
                                        continue;
                                }

                                /*
                                 * If the two groups have the same stream instance id
                                 * and belong to the same stream class (stream instance
                                 * ids are per-stream class), they represent the same
                                 * stream instance.
                                 */
                                if (candidate_dest->stream_id != src_group->stream_id ||
                                                candidate_dest->sc->id != src_group->sc->id) {
                                        continue;
                                }

                                dest_group = candidate_dest;
                                break;
                        }
                }

                /*
                 * Didn't find a friend in dest to merge our src_group into?
                 * Create a new empty one. This can happen if a stream was
                 * active in the source trace chunk but not in the destination
                 * trace chunk.
                 */
                if (!dest_group) {
                        struct ctf_stream_class *sc;
                        struct ctf_fs_ds_index *index;

                        sc = ctf_trace_class_borrow_stream_class_by_id(
                                dest_trace->metadata->tc, src_group->sc->id);
                        BT_ASSERT(sc);

                        index = ctf_fs_ds_index_create(dest_trace->log_level,
                                dest_trace->self_comp);
                        if (!index) {
                                ret = -1;
                                goto end;
                        }

                        dest_group = ctf_fs_ds_file_group_create(dest_trace, sc,
                                src_group->stream_id, index);
                        /* Ownership of index is transferred. */
                        index = NULL;
                        if (!dest_group) {
                                ret = -1;
                                goto end;
                        }

                        g_ptr_array_add(dest_trace->ds_file_groups, dest_group);
                }

                BT_ASSERT(dest_group);
                merge_ctf_fs_ds_file_groups(dest_group, src_group);
        }

end:
        return ret;
}

/*
 * Collapse the given traces, which must all share the same UUID, in a single
 * one.
 *
 * The trace with the most expansive metadata is chosen and all other traces
 * are merged into that one.  The array slots of all the traces that get merged
 * in the chosen one are set to NULL, so only the slot of the chosen trace
 * remains non-NULL.
 */

static
int merge_ctf_fs_traces(struct ctf_fs_trace **traces, unsigned int num_traces)
{
        unsigned int winner_count;
        struct ctf_fs_trace *winner;
        guint i;
        int ret = 0;
        char uuid_str[BT_UUID_STR_LEN + 1];

        BT_ASSERT(num_traces >= 2);

        winner_count = metadata_count_stream_and_event_classes(traces[0]);
        winner = traces[0];

        /* Find the trace with the largest metadata. */
        for (i = 1; i < num_traces; i++) {
                struct ctf_fs_trace *candidate;
                unsigned int candidate_count;

                candidate = traces[i];

                /* A bit of sanity check. */
                BT_ASSERT(bt_uuid_compare(winner->metadata->tc->uuid, candidate->metadata->tc->uuid) == 0);

                candidate_count = metadata_count_stream_and_event_classes(candidate);

                if (candidate_count > winner_count) {
                        winner_count = candidate_count;
                        winner = candidate;
                }
        }

        /* Merge all the other traces in the winning trace. */
        for (i = 0; i < num_traces; i++) {
                struct ctf_fs_trace *trace = traces[i];

                /* Don't merge the winner into itself. */
                if (trace == winner) {
                        continue;
                }

                /* Merge trace's data stream file groups into winner's. */
                ret = merge_matching_ctf_fs_ds_file_groups(winner, trace);
                if (ret) {
                        goto end;
                }

                /* Free the trace that got merged into winner, clear the slot in the array. */
                ctf_fs_trace_destroy(trace);
                traces[i] = NULL;
        }

        /* Use the string representation of the UUID as the trace name. */
        bt_uuid_to_str(winner->metadata->tc->uuid, uuid_str);
        g_string_printf(winner->name, "%s", uuid_str);

end:
        return ret;
}

/*
 * Merge all traces of `ctf_fs` that share the same UUID in a single trace.
 * Traces with no UUID are not merged.
 */

static
int merge_traces_with_same_uuid(struct ctf_fs_component *ctf_fs)
{
        GPtrArray *traces = ctf_fs->traces;
        guint range_start_idx = 0;
        unsigned int num_traces = 0;
        guint i;
        int ret = 0;

        /* Sort the traces by uuid, then collapse traces with the same uuid in a single one. */
        g_ptr_array_sort(traces, sort_traces_by_uuid);

        /* Find ranges of consecutive traces that share the same UUID.  */
        while (range_start_idx < traces->len) {
                guint range_len;
                struct ctf_fs_trace *range_start_trace = g_ptr_array_index(traces, range_start_idx);

                /* Exclusive end of range. */
                guint range_end_exc_idx = range_start_idx + 1;

                while (range_end_exc_idx < traces->len) {
                        struct ctf_fs_trace *this_trace = g_ptr_array_index(traces, range_end_exc_idx);

                        if (!range_start_trace->metadata->tc->is_uuid_set ||
                                (bt_uuid_compare(range_start_trace->metadata->tc->uuid, this_trace->metadata->tc->uuid) != 0)) {
                                break;
                        }

                        range_end_exc_idx++;
                }

                /* If we have two or more traces with matching UUIDs, merge them. */
                range_len = range_end_exc_idx - range_start_idx;
                if (range_len > 1) {
                        struct ctf_fs_trace **range_start = (struct ctf_fs_trace **) &traces->pdata[range_start_idx];
                        ret = merge_ctf_fs_traces(range_start, range_len);
                        if (ret) {
                                goto end;
                        }
                }

                num_traces++;
                range_start_idx = range_end_exc_idx;
        }

        /* Clear any NULL slot (traces that got merged in another one) in the array.  */
        for (i = 0; i < traces->len;) {
                if (!g_ptr_array_index(traces, i)) {
                        g_ptr_array_remove_index_fast(traces, i);
                } else {
                        i++;
                }
        }

        BT_ASSERT(num_traces == traces->len);

end:
        return ret;
}

enum target_event {
        FIRST_EVENT,
        LAST_EVENT,
};

static
int decode_clock_snapshot_after_event(struct ctf_fs_trace *ctf_fs_trace,
        struct ctf_clock_class *default_cc,
        struct ctf_fs_ds_index_entry *index_entry,
        enum target_event target_event, uint64_t *cs, int64_t *ts_ns)
{
        enum bt_msg_iter_status iter_status = BT_MSG_ITER_STATUS_OK;
        struct ctf_fs_ds_file *ds_file = NULL;
        struct bt_msg_iter *msg_iter = NULL;
        bt_logging_level log_level = ctf_fs_trace->log_level;
        bt_self_component *self_comp = ctf_fs_trace->self_comp;
        int ret = 0;

        BT_ASSERT(ctf_fs_trace);
        BT_ASSERT(ctf_fs_trace->metadata);
        BT_ASSERT(ctf_fs_trace->metadata->tc);

        msg_iter = bt_msg_iter_create(ctf_fs_trace->metadata->tc,
                bt_common_get_page_size(log_level) * 8, ctf_fs_ds_file_medops,
                NULL, log_level, self_comp);
        if (!msg_iter) {
                /* bt_msg_iter_create() logs errors. */
                ret = -1;
                goto end;
        }

        BT_ASSERT(index_entry);
        BT_ASSERT(index_entry->path);

        ds_file = ctf_fs_ds_file_create(ctf_fs_trace, NULL, msg_iter,
                NULL, index_entry->path, log_level);
        if (!ds_file) {
                BT_LOGE_STR("Failed to create a ctf_fs_ds_file");
                ret = -1;
                goto end;
        }

        /*
         * Turn on dry run mode to prevent the creation and usage of Babeltrace
         * library objects (bt_field, bt_message_*, etc.).
         */
        bt_msg_iter_set_dry_run(msg_iter, true);

        /* Seek to the beginning of the target packet. */
        iter_status = bt_msg_iter_seek(ds_file->msg_iter, index_entry->offset);
        if (iter_status) {
                /* bt_msg_iter_seek() logs errors. */
                ret = -1;
                goto end;
        }

        switch (target_event) {
        case FIRST_EVENT:
                /*
                 * Start to decode the packet until we reach the end of
                 * the first event. To extract the first event's clock
                 * snapshot.
                 */
                iter_status = bt_msg_iter_curr_packet_first_event_clock_snapshot(
                        ds_file->msg_iter, cs);
                break;
        case LAST_EVENT:
                /* Decode the packet to extract the last event's clock snapshot. */
                iter_status = bt_msg_iter_curr_packet_last_event_clock_snapshot(
                        ds_file->msg_iter, cs);
                break;
        default:
                abort();
        }
        if (iter_status) {
                ret = -1;
                goto end;
        }

        /* Convert clock snapshot to timestamp. */
        ret = bt_util_clock_cycles_to_ns_from_origin(*cs,
                default_cc->frequency, default_cc->offset_seconds,
                default_cc->offset_cycles, ts_ns);
        if (ret) {
                BT_LOGE_STR("Failed to convert clock snapshot to timestamp");
                goto end;
        }

end:
        if (ds_file) {
                ctf_fs_ds_file_destroy(ds_file);
        }
        if (msg_iter) {
                bt_msg_iter_destroy(msg_iter);
        }

        return ret;
}

static
int decode_packet_first_event_timestamp(struct ctf_fs_trace *ctf_fs_trace,
        struct ctf_clock_class *default_cc,
        struct ctf_fs_ds_index_entry *index_entry, uint64_t *cs, int64_t *ts_ns)
{
        return decode_clock_snapshot_after_event(ctf_fs_trace, default_cc,
                index_entry, FIRST_EVENT, cs, ts_ns);
}

static
int decode_packet_last_event_timestamp(struct ctf_fs_trace *ctf_fs_trace,
        struct ctf_clock_class *default_cc,
        struct ctf_fs_ds_index_entry *index_entry, uint64_t *cs, int64_t *ts_ns)
{
        return decode_clock_snapshot_after_event(ctf_fs_trace, default_cc,
                index_entry, LAST_EVENT, cs, ts_ns);
}

/*
 * Fix up packet index entries for lttng's "event-after-packet" bug.
 * Some buggy lttng tracer versions may emit events with a timestamp that is
 * larger (after) than the timestamp_end of the their packets.
 *
 * To fix up this erroneous data we do the following:
 *  1. If it's not the stream file's last packet: set the packet index entry's
 *      end time to the next packet's beginning time.
 *  2. If it's the stream file's last packet, set the packet index entry's end
 *      time to the packet's last event's time, if any, or to the packet's
 *      beginning time otherwise.
 *
 * Known buggy tracer versions:
 *  - before lttng-ust 2.11.0
 *  - before lttng-module 2.11.0
 *  - before lttng-module 2.10.10
 *  - before lttng-module 2.9.13
 */
static
int fix_index_lttng_event_after_packet_bug(struct ctf_fs_trace *trace)
{
        int ret = 0;
        guint ds_file_group_i;
        GPtrArray *ds_file_groups = trace->ds_file_groups;
        bt_logging_level log_level = trace->log_level;

        for (ds_file_group_i = 0; ds_file_group_i < ds_file_groups->len;
                        ds_file_group_i++) {
                guint entry_i;
                struct ctf_clock_class *default_cc;
                struct ctf_fs_ds_index_entry *last_entry;
                struct ctf_fs_ds_index *index;

                struct ctf_fs_ds_file_group *ds_file_group =
                        g_ptr_array_index(ds_file_groups, ds_file_group_i);

                BT_ASSERT(ds_file_group);
                index = ds_file_group->index;

                BT_ASSERT(index);
                BT_ASSERT(index->entries);
                BT_ASSERT(index->entries->len > 0);

                /*
                 * Iterate over all entries but the last one. The last one is
                 * fixed differently after.
                 */
                for (entry_i = 0; entry_i < index->entries->len - 1;
                                entry_i++) {
                        struct ctf_fs_ds_index_entry *curr_entry, *next_entry;

                        curr_entry = g_ptr_array_index(index->entries, entry_i);
                        next_entry = g_ptr_array_index(index->entries, entry_i + 1);

                        /*
                         * 1. Set the current index entry `end` timestamp to
                         * the next index entry `begin` timestamp.
                         */
                        curr_entry->timestamp_end = next_entry->timestamp_begin;
                        curr_entry->timestamp_end_ns = next_entry->timestamp_begin_ns;
                }

                /*
                 * 2. Fix the last entry by decoding the last event of the last
                 * packet.
                 */
                last_entry = g_ptr_array_index(index->entries,
                        index->entries->len - 1);
                BT_ASSERT(last_entry);

                BT_ASSERT(ds_file_group->sc->default_clock_class);
                default_cc = ds_file_group->sc->default_clock_class;

                /*
                 * Decode packet to read the timestamp of the last event of the
                 * entry.
                 */
                ret = decode_packet_last_event_timestamp(trace, default_cc,
                        last_entry, &last_entry->timestamp_end,
                        &last_entry->timestamp_end_ns);
                if (ret) {
                        BT_LOGE_STR("Failed to decode stream's last packet to get its last event's clock snapshot.");
                        goto end;
                }
        }

end:
        return ret;
}

/*
 * Fix up packet index entries for barectf's "event-before-packet" bug.
 * Some buggy barectf tracer versions may emit events with a timestamp that is
 * less than the timestamp_begin of the their packets.
 *
 * To fix up this erroneous data we do the following:
 *  1. Starting at the second index entry, set the timestamp_begin of the
 *     current entry to the timestamp of the first event of the packet.
 *  2. Set the previous entry's timestamp_end to the timestamp_begin of the
 *     current packet.
 *
 * Known buggy tracer versions:
 *  - before barectf 2.3.1
 */
static
int fix_index_barectf_event_before_packet_bug(struct ctf_fs_trace *trace)
{
        int ret = 0;
        guint ds_file_group_i;
        GPtrArray *ds_file_groups = trace->ds_file_groups;
        bt_logging_level log_level = trace->log_level;

        for (ds_file_group_i = 0; ds_file_group_i < ds_file_groups->len;
                        ds_file_group_i++) {
                guint entry_i;
                struct ctf_clock_class *default_cc;
                struct ctf_fs_ds_file_group *ds_file_group =
                        g_ptr_array_index(ds_file_groups, ds_file_group_i);

                struct ctf_fs_ds_index *index = ds_file_group->index;

                BT_ASSERT(index);
                BT_ASSERT(index->entries);
                BT_ASSERT(index->entries->len > 0);

                BT_ASSERT(ds_file_group->sc->default_clock_class);
                default_cc = ds_file_group->sc->default_clock_class;

                /*
                 * 1. Iterate over the index, starting from the second entry
                 * (index = 1).
                 */
                for (entry_i = 1; entry_i < index->entries->len;
                                entry_i++) {
                        struct ctf_fs_ds_index_entry *curr_entry, *prev_entry;
                        prev_entry = g_ptr_array_index(index->entries, entry_i - 1);
                        curr_entry = g_ptr_array_index(index->entries, entry_i);
                        /*
                         * 2. Set the current entry `begin` timestamp to the
                         * timestamp of the first event of the current packet.
                         */
                        ret = decode_packet_first_event_timestamp(trace, default_cc,
                                curr_entry, &curr_entry->timestamp_begin,
                                &curr_entry->timestamp_begin_ns);
                        if (ret) {
                                BT_LOGE_STR("Failed to decode first event's clock snapshot");
                                goto end;
                        }

                        /*
                         * 3. Set the previous entry `end` timestamp to the
                         * timestamp of the first event of the current packet.
                         */
                        prev_entry->timestamp_end = curr_entry->timestamp_begin;
                        prev_entry->timestamp_end_ns = curr_entry->timestamp_begin_ns;
                }
        }
end:
        return ret;
}

/*
 * When using the lttng-crash feature it's likely that the last packets of each
 * stream have their timestamp_end set to zero. This is caused by the fact that
 * the tracer crashed and was not able to properly close the packets.
 *
 * To fix up this erroneous data we do the following:
 * For each index entry, if the entry's timestamp_end is 0 and the
 * timestamp_begin is not 0:
 *  - If it's the stream file's last packet: set the packet index entry's end
 *    time to the packet's last event's time, if any, or to the packet's
 *    beginning time otherwise.
 *  - If it's not the stream file's last packet: set the packet index
 *    entry's end time to the next packet's beginning time.
 *
 * Affected versions:
 * - All current and future lttng-ust and lttng-modules versions.
 */
static
int fix_index_lttng_crash_quirk(struct ctf_fs_trace *trace)
{
        int ret = 0;
        guint ds_file_group_idx;
        GPtrArray *ds_file_groups = trace->ds_file_groups;
        bt_logging_level log_level = trace->log_level;

        for (ds_file_group_idx = 0; ds_file_group_idx < ds_file_groups->len;
                        ds_file_group_idx++) {
                guint entry_idx;
                struct ctf_clock_class *default_cc;
                struct ctf_fs_ds_index_entry *last_entry;
                struct ctf_fs_ds_index *index;

                struct ctf_fs_ds_file_group *ds_file_group =
                        g_ptr_array_index(ds_file_groups, ds_file_group_idx);

                BT_ASSERT(ds_file_group);
                index = ds_file_group->index;

                BT_ASSERT(ds_file_group->sc->default_clock_class);
                default_cc = ds_file_group->sc->default_clock_class;

                BT_ASSERT(index);
                BT_ASSERT(index->entries);
                BT_ASSERT(index->entries->len > 0);

                last_entry = g_ptr_array_index(index->entries,
                        index->entries->len - 1);
                BT_ASSERT(last_entry);


                /* 1. Fix the last entry first. */
                if (last_entry->timestamp_end == 0 &&
                                last_entry->timestamp_begin != 0) {
                        /*
                         * Decode packet to read the timestamp of the
                         * last event of the stream file.
                         */
                        ret = decode_packet_last_event_timestamp(trace,
                                default_cc, last_entry,
                                &last_entry->timestamp_end,
                                &last_entry->timestamp_end_ns);
                        if (ret) {
                                BT_LOGE_STR("Failed to decode last event's clock snapshot");
                                goto end;
                        }
                }

                /* Iterate over all entries but the last one. */
                for (entry_idx = 0; entry_idx < index->entries->len - 1;
                                entry_idx++) {
                        struct ctf_fs_ds_index_entry *curr_entry, *next_entry;
                        curr_entry = g_ptr_array_index(index->entries, entry_idx);
                        next_entry = g_ptr_array_index(index->entries, entry_idx + 1);

                        if (curr_entry->timestamp_end == 0 &&
                                        curr_entry->timestamp_begin != 0) {
                                /*
                                 * 2. Set the current index entry `end` timestamp to
                                 * the next index entry `begin` timestamp.
                                 */
                                curr_entry->timestamp_end = next_entry->timestamp_begin;
                                curr_entry->timestamp_end_ns = next_entry->timestamp_begin_ns;
                        }
                }
        }

end:
        return ret;
}

/*
 * Extract the tracer information necessary to compare versions.
 * Returns 0 on success, and -1 if the extraction is not successful because the
 * necessary fields are absents in the trace metadata.
 */
static
int extract_tracer_info(struct ctf_fs_trace *trace,
                struct tracer_info *current_tracer_info)
{
        int ret = 0;
        struct ctf_trace_class_env_entry *entry;

        /* Clear the current_tracer_info struct */
        memset(current_tracer_info, 0, sizeof(*current_tracer_info));

        /*
         * To compare 2 tracer versions, at least the tracer name and it's
         * major version are needed. If one of these is missing, consider it an
         * extraction failure.
         */
        entry = ctf_trace_class_borrow_env_entry_by_name(
                trace->metadata->tc, "tracer_name");
        if (!entry || entry->type != CTF_TRACE_CLASS_ENV_ENTRY_TYPE_STR) {
                goto missing_bare_minimum;
        }

        /* Set tracer name. */
        current_tracer_info->name = entry->value.str->str;

        entry = ctf_trace_class_borrow_env_entry_by_name(
                trace->metadata->tc, "tracer_major");
        if (!entry || entry->type != CTF_TRACE_CLASS_ENV_ENTRY_TYPE_INT) {
                goto missing_bare_minimum;
        }

        /* Set major version number. */
        current_tracer_info->major = entry->value.i;

        entry = ctf_trace_class_borrow_env_entry_by_name(
                trace->metadata->tc, "tracer_minor");
        if (!entry || entry->type != CTF_TRACE_CLASS_ENV_ENTRY_TYPE_INT) {
                goto end;
        }

        /* Set minor version number. */
        current_tracer_info->minor = entry->value.i;

        entry = ctf_trace_class_borrow_env_entry_by_name(
                trace->metadata->tc, "tracer_patch");
        if (!entry) {
                /*
                 * If `tracer_patch` doesn't exist `tracer_patchlevel` might.
                 * For example, `lttng-modules` uses entry name
                 * `tracer_patchlevel`.
                 */
                entry = ctf_trace_class_borrow_env_entry_by_name(
                        trace->metadata->tc, "tracer_patchlevel");
        }

        if (!entry || entry->type != CTF_TRACE_CLASS_ENV_ENTRY_TYPE_INT) {
                goto end;
        }

        /* Set patch version number. */
        current_tracer_info->patch = entry->value.i;

        goto end;

missing_bare_minimum:
        ret = -1;
end:
        return ret;
}

static
bool is_tracer_affected_by_lttng_event_after_packet_bug(
                struct tracer_info *curr_tracer_info)
{
        bool is_affected = false;

        if (strcmp(curr_tracer_info->name, "lttng-ust") == 0) {
                if (curr_tracer_info->major < 2) {
                        is_affected = true;
                } else if (curr_tracer_info->major == 2) {
                        /* fixed in lttng-ust 2.11.0 */
                        if (curr_tracer_info->minor < 11) {
                                is_affected = true;
                        }
                }
        } else if (strcmp(curr_tracer_info->name, "lttng-modules") == 0) {
                if (curr_tracer_info->major < 2) {
                        is_affected = true;
                } else if (curr_tracer_info->major == 2) {
                        /* fixed in lttng-modules 2.11.0 */
                        if (curr_tracer_info->minor == 10) {
                                /* fixed in lttng-modules 2.10.10 */
                                if (curr_tracer_info->patch < 10) {
                                        is_affected = true;
                                }
                        } else if (curr_tracer_info->minor == 9) {
                                /* fixed in lttng-modules 2.9.13 */
                                if (curr_tracer_info->patch < 13) {
                                        is_affected = true;
                                }
                        } else if (curr_tracer_info->minor < 9) {
                                is_affected = true;
                        }
                }
        }

        return is_affected;
}

static
bool is_tracer_affected_by_barectf_event_before_packet_bug(
                struct tracer_info *curr_tracer_info)
{
        bool is_affected = false;

        if (strcmp(curr_tracer_info->name, "barectf") == 0) {
                if (curr_tracer_info->major < 2) {
                        is_affected = true;
                } else if (curr_tracer_info->major == 2) {
                        if (curr_tracer_info->minor < 3) {
                                is_affected = true;
                        } else if (curr_tracer_info->minor == 3) {
                                /* fixed in barectf 2.3.1 */
                                if (curr_tracer_info->patch < 1) {
                                        is_affected = true;
                                }
                        }
                }
        }

        return is_affected;
}

static
bool is_tracer_affected_by_lttng_crash_quirk(
                struct tracer_info *curr_tracer_info)
{
        bool is_affected = false;

        /* All LTTng tracer may be affected by this lttng crash quirk. */
        if (strcmp(curr_tracer_info->name, "lttng-ust") == 0) {
                is_affected = true;
        } else if (strcmp(curr_tracer_info->name, "lttng-modules") == 0) {
                is_affected = true;
        }

        return is_affected;
}

/*
 * Looks for trace produced by known buggy tracers and fix up the index
 * produced earlier.
 */
static
int fix_packet_index_tracer_bugs(struct ctf_fs_component *ctf_fs)
{
        int ret = 0;
        guint trace_i;
        struct tracer_info current_tracer_info;
        GPtrArray *traces = ctf_fs->traces;
        bt_logging_level log_level = ctf_fs->log_level;

        /*
         * Iterate over all the traces of this component and check for
         * possible indexing bugs.
         */
        for (trace_i = 0; trace_i < traces->len; trace_i++) {
                struct ctf_fs_trace *trace = g_ptr_array_index(traces,
                        trace_i);

                ret = extract_tracer_info(trace, &current_tracer_info);
                if (ret) {
                        /*
                         * A trace may not have all the necessary environment
                         * entries to do the tracer version comparison.
                         * At least, the tracer name and major version number
                         * are needed. Failing to extract these entries is not
                         * an error.
                         */
                        ret = 0;
                        BT_LOGI_STR("Cannot extract tracer information necessary to compare with buggy versions.");
                        continue;
                }

                /* Check if the trace may be affected by old tracer bugs. */
                if (is_tracer_affected_by_lttng_event_after_packet_bug(
                                &current_tracer_info)) {
                        BT_LOGI_STR("Trace may be affected by LTTng tracer packet timestamp bug. Fixing up.");
                        ret = fix_index_lttng_event_after_packet_bug(trace);
                        if (ret) {
                                BT_LOGE_STR("Failed to fix LTTng event-after-packet bug.");
                                goto end;
                        }
                }

                if (is_tracer_affected_by_barectf_event_before_packet_bug(
                                &current_tracer_info)) {
                        BT_LOGI_STR("Trace may be affected by barectf tracer packet timestamp bug. Fixing up.");
                        ret = fix_index_barectf_event_before_packet_bug(trace);
                        if (ret) {
                                BT_LOGE_STR("Failed to fix barectf event-before-packet bug.");
                                goto end;
                        }
                }

                if (is_tracer_affected_by_lttng_crash_quirk(
                                &current_tracer_info)) {
                        ret = fix_index_lttng_crash_quirk(trace);
                        if (ret) {
                                BT_LOGE_STR("Failed to fix lttng-crash timestamp quirks.");
                                goto end;
                        }
                }
        }
end:
        return ret;
}

int ctf_fs_component_create_ctf_fs_traces(bt_self_component_source *self_comp,
                struct ctf_fs_component *ctf_fs,
                const bt_value *paths_value)
{
        int ret = 0;
        uint64_t i;
        bt_logging_level log_level = ctf_fs->log_level;

        for (i = 0; i < bt_value_array_get_length(paths_value); i++) {
                const bt_value *path_value = bt_value_array_borrow_element_by_index_const(paths_value, i);
                const char *input = bt_value_string_get(path_value);

                ret = ctf_fs_component_create_ctf_fs_traces_one_root(ctf_fs,
                        input);
                if (ret) {
                        goto end;
                }
        }

        ret = merge_traces_with_same_uuid(ctf_fs);
        if (ret) {
                BT_LOGE_STR("Failed to merge traces with the same UUID.");
        }

        ret = fix_packet_index_tracer_bugs(ctf_fs);
        if (ret) {
                BT_LOGE_STR("Failed to fix packet index tracer bugs.");
        }
end:
        return ret;
}

static
GString *get_stream_instance_unique_name(
                struct ctf_fs_ds_file_group *ds_file_group)
{
        GString *name;
        struct ctf_fs_ds_file_info *ds_file_info;

        name = g_string_new(NULL);
        if (!name) {
                goto end;
        }

        /*
         * If there's more than one stream file in the stream file
         * group, the first (earliest) stream file's path is used as
         * the stream's unique name.
         */
        BT_ASSERT(ds_file_group->ds_file_infos->len > 0);
        ds_file_info = g_ptr_array_index(ds_file_group->ds_file_infos, 0);
        g_string_assign(name, ds_file_info->path->str);

end:
        return name;
}

/* Create the IR stream objects for ctf_fs_trace. */

static
int create_streams_for_trace(struct ctf_fs_trace *ctf_fs_trace)
{
        int ret;
        GString *name = NULL;
        guint i;
        bt_logging_level log_level = ctf_fs_trace->log_level;
        bt_self_component *self_comp = ctf_fs_trace->self_comp;

        for (i = 0; i < ctf_fs_trace->ds_file_groups->len; i++) {
                struct ctf_fs_ds_file_group *ds_file_group =
                        g_ptr_array_index(ctf_fs_trace->ds_file_groups, i);
                name = get_stream_instance_unique_name(ds_file_group);

                if (!name) {
                        goto error;
                }

                if (ds_file_group->sc->ir_sc) {
                        BT_ASSERT(ctf_fs_trace->trace);

                        if (ds_file_group->stream_id == UINT64_C(-1)) {
                                /* No stream ID: use 0 */
                                ds_file_group->stream = bt_stream_create_with_id(
                                        ds_file_group->sc->ir_sc,
                                        ctf_fs_trace->trace,
                                        ctf_fs_trace->next_stream_id);
                                ctf_fs_trace->next_stream_id++;
                        } else {
                                /* Specific stream ID */
                                ds_file_group->stream = bt_stream_create_with_id(
                                        ds_file_group->sc->ir_sc,
                                        ctf_fs_trace->trace,
                                        (uint64_t) ds_file_group->stream_id);
                        }
                } else {
                        ds_file_group->stream = NULL;
                }

                if (!ds_file_group->stream) {
                        BT_COMP_LOGE("Cannot create stream for DS file group: "
                                "addr=%p, stream-name=\"%s\"",
                                ds_file_group, name->str);
                        goto error;
                }

                ret = bt_stream_set_name(ds_file_group->stream,
                        name->str);
                if (ret) {
                        BT_COMP_LOGE("Cannot set stream's name: "
                                "addr=%p, stream-name=\"%s\"",
                                ds_file_group->stream, name->str);
                        goto error;
                }

                g_string_free(name, TRUE);
                name = NULL;
        }

        ret = 0;
        goto end;

error:
        ret = -1;

end:

        if (name) {
                g_string_free(name, TRUE);
        }
        return ret;
}

/*
 * Validate the "paths" parameter passed to this component.  It must be
 * present, and it must be an array of strings.
 */

static
bool validate_inputs_parameter(struct ctf_fs_component *ctf_fs,
                const bt_value *inputs)
{
        bool ret;
        bt_value_type type;
        uint64_t i;
        bt_logging_level log_level = ctf_fs->log_level;
        bt_self_component *self_comp = ctf_fs->self_comp;

        if (!inputs) {
                BT_COMP_LOGE("missing \"inputs\" parameter");
                goto error;
        }

        type = bt_value_get_type(inputs);
        if (type != BT_VALUE_TYPE_ARRAY) {
                BT_COMP_LOGE("`inputs` parameter: expecting array value: type=%s",
                        bt_common_value_type_string(type));
                goto error;
        }

        for (i = 0; i < bt_value_array_get_length(inputs); i++) {
                const bt_value *elem;

                elem = bt_value_array_borrow_element_by_index_const(inputs, i);
                type = bt_value_get_type(elem);
                if (type != BT_VALUE_TYPE_STRING) {
                        BT_COMP_LOGE("`inputs` parameter: expecting string value: index=%" PRIu64 ", type=%s",
                                i, bt_common_value_type_string(type));
                        goto error;
                }
        }

        ret = true;
        goto end;

error:
        ret = false;

end:
        return ret;
}

bool read_src_fs_parameters(const bt_value *params,
                const bt_value **inputs, struct ctf_fs_component *ctf_fs) {
        bool ret;
        const bt_value *value;
        bt_logging_level log_level = ctf_fs->log_level;
        bt_self_component *self_comp = ctf_fs->self_comp;

        /* inputs parameter */
        *inputs = bt_value_map_borrow_entry_value_const(params, "inputs");
        if (!validate_inputs_parameter(ctf_fs, *inputs)) {
                goto error;
        }

        /* clock-class-offset-s parameter */
        value = bt_value_map_borrow_entry_value_const(params,
                "clock-class-offset-s");
        if (value) {
                if (!bt_value_is_signed_integer(value)) {
                        BT_COMP_LOGE("clock-class-offset-s must be an integer");
                        goto error;
                }
                ctf_fs->metadata_config.clock_class_offset_s =
                        bt_value_integer_signed_get(value);
        }

        /* clock-class-offset-ns parameter */
        value = bt_value_map_borrow_entry_value_const(params,
                "clock-class-offset-ns");
        if (value) {
                if (!bt_value_is_signed_integer(value)) {
                        BT_COMP_LOGE("clock-class-offset-ns must be an integer");
                        goto error;
                }
                ctf_fs->metadata_config.clock_class_offset_ns =
                        bt_value_integer_signed_get(value);
        }


        ret = true;
        goto end;

error:
        ret = false;

end:
        return ret;
}

static
struct ctf_fs_component *ctf_fs_create(
                bt_self_component_source *self_comp_src,
                const bt_value *params)
{
        struct ctf_fs_component *ctf_fs = NULL;
        guint i;
        const bt_value *inputs_value;
        bt_self_component *self_comp =
                bt_self_component_source_as_self_component(self_comp_src);

        ctf_fs = ctf_fs_component_create(bt_component_get_logging_level(
                bt_self_component_as_component(self_comp)), self_comp);
        if (!ctf_fs) {
                goto error;
        }

        if (!read_src_fs_parameters(params, &inputs_value, ctf_fs)) {
                goto error;
        }

        bt_self_component_set_data(self_comp, ctf_fs);
        ctf_fs->self_comp = self_comp;
        ctf_fs->self_comp_src = self_comp_src;

        if (ctf_fs_component_create_ctf_fs_traces(self_comp_src, ctf_fs, inputs_value)) {
                goto error;
        }

        for (i = 0; i < ctf_fs->traces->len; i++) {
                struct ctf_fs_trace *trace = g_ptr_array_index(ctf_fs->traces, i);

                if (create_streams_for_trace(trace)) {
                        goto error;
                }

                if (create_ports_for_trace(ctf_fs, trace)) {
                        goto error;
                }
        }

        goto end;

error:
        ctf_fs_destroy(ctf_fs);
        ctf_fs = NULL;
        bt_self_component_set_data(self_comp, NULL);

end:
        return ctf_fs;
}

BT_HIDDEN
bt_component_class_init_method_status ctf_fs_init(
                bt_self_component_source *self_comp,
                const bt_value *params, __attribute__((unused)) void *init_method_data)
{
        struct ctf_fs_component *ctf_fs;
        bt_component_class_init_method_status ret =
                BT_COMPONENT_CLASS_INIT_METHOD_STATUS_OK;

        ctf_fs = ctf_fs_create(self_comp, params);
        if (!ctf_fs) {
                ret = BT_COMPONENT_CLASS_INIT_METHOD_STATUS_ERROR;
        }

        return ret;
}

BT_HIDDEN
bt_component_class_query_method_status ctf_fs_query(
                bt_self_component_class_source *comp_class,
                bt_private_query_executor *priv_query_exec,
                const char *object, const bt_value *params,
                __attribute__((unused)) void *method_data,
                const bt_value **result)
{
        bt_component_class_query_method_status status =
                BT_COMPONENT_CLASS_QUERY_METHOD_STATUS_OK;
        bt_logging_level log_level = bt_query_executor_get_logging_level(
                bt_private_query_executor_as_query_executor_const(
                        priv_query_exec));

        if (strcmp(object, "metadata-info") == 0) {
                status = metadata_info_query(comp_class, params, log_level,
                        result);
        } else if (strcmp(object, "babeltrace.trace-info") == 0) {
                status = trace_info_query(comp_class, params, log_level,
                        result);
        } else if (!strcmp(object, "babeltrace.support-info")) {
                status = support_info_query(comp_class, params, log_level, result);
        } else {
                BT_LOGE("Unknown query object `%s`", object);
                status = BT_COMPONENT_CLASS_QUERY_METHOD_STATUS_UNKNOWN_OBJECT;
                goto end;
        }
end:
        return status;
}