+++ /dev/null
-/*
- * SPDX-License-Identifier: MIT
- *
- * Copyright (c) 2015-2016 EfficiOS Inc. and Linux Foundation
- * Copyright (c) 2015-2016 Philippe Proulx <pproulx@efficios.com>
- *
- * Babeltrace - CTF binary field class reader (BFCR)
- */
-
-#ifndef CTF_BFCR_H
-#define CTF_BFCR_H
-
-#include <stddef.h>
-#include <stdint.h>
-
-#include <babeltrace2/babeltrace.h>
-
-#include "common/common.h"
-
-/**
- * @file bfcr.h
- *
- * Event-driven CTF binary field class reader (BFCR).
- *
- * This is a common, internal API used by CTF source plugins. It allows
- * a binary CTF IR field class to be decoded from user-provided buffers.
- * As the class is decoded (and, possibly, its nested classes),
- * registered user callback functions are called.
- *
- * This API is only concerned with reading one CTF class at a time from
- * one or more buffer of bytes. It does not know CTF dynamic scopes,
- * events, or streams. Sequence lengths and selected variant classes are
- * requested to the user when needed.
- */
-
-/**
- * Binary class reader API status codes.
- */
-enum bt_bfcr_status
-{
- /** Out of memory. */
- BT_BFCR_STATUS_ENOMEM = -5,
- /**
- * The binary stream reader reached the end of the user-provided
- * buffer, but data is still needed to finish decoding the
- * requested class.
- *
- * The user needs to call bt_bfcr_continue() as long as
- * #BT_BFCR_STATUS_EOF is returned to complete the decoding
- * process of a given class.
- */
- BT_BFCR_STATUS_EOF = 1,
-
- /** Invalid argument. */
- BT_BFCR_STATUS_INVAL = -3,
-
- /** General error. */
- BT_BFCR_STATUS_ERROR = -1,
-
- /** Everything okay. */
- BT_BFCR_STATUS_OK = 0,
-};
-
-typedef enum bt_bfcr_status (*bt_bfcr_unsigned_int_cb_func)(uint64_t, struct ctf_field_class *,
- void *);
-
-/*
- * Field class reader user callback functions.
- */
-struct bt_bfcr_cbs
-{
- /**
- * Field class callback functions.
- *
- * This CTF binary class reader is event-driven. The following
- * functions are called during the decoding process, either when
- * a compound class begins/ends, or when a basic class is
- * completely decoded (along with its value).
- *
- * Each function also receives the CTF field class associated
- * with the call, and user data (registered to the class reader
- * calling them).
- *
- * Actual trace IR fields are \em not created here; this would
- * be the responsibility of a class reader's user (the provider
- * of those callback functions).
- *
- * All the class callback functions return one of the following
- * values:
- *
- * - <b>#BT_BFCR_STATUS_OK</b>: Everything is okay;
- * continue the decoding process.
- * - <b>#BT_BFCR_STATUS_ERROR</b>: General error (reported
- * to class reader's user).
- *
- * Any member of this structure may be set to \c NULL, should
- * a specific message be not needed.
- */
- struct
- {
- /**
- * Called when a signed integer class is completely
- * decoded. This could also be the supporting signed
- * integer class of an enumeration class (\p class will
- * indicate this).
- *
- * @param value Signed integer value
- * @param class Integer or enumeration class
- * @param data User data
- * @returns #BT_BFCR_STATUS_OK or
- * #BT_BFCR_STATUS_ERROR
- */
- enum bt_bfcr_status (*signed_int)(int64_t value, struct ctf_field_class *cls, void *data);
-
- /**
- * Called when an unsigned integer class is completely
- * decoded. This could also be the supporting signed
- * integer class of an enumeration class (\p class will
- * indicate this).
- *
- * @param value Unsigned integer value
- * @param class Integer or enumeration class
- * @param data User data
- * @returns #BT_BFCR_STATUS_OK or
- * #BT_BFCR_STATUS_ERROR
- */
- bt_bfcr_unsigned_int_cb_func unsigned_int;
-
- /**
- * Called when a floating point number class is
- * completely decoded.
- *
- * @param value Floating point number value
- * @param class Floating point number class
- * @param data User data
- * @returns #BT_BFCR_STATUS_OK or
- * #BT_BFCR_STATUS_ERROR
- */
- enum bt_bfcr_status (*floating_point)(double value, struct ctf_field_class *cls,
- void *data);
-
- /**
- * Called when a string class begins.
- *
- * All the following user callback function calls will
- * be made to bt_bfcr_cbs::classes::string(), each of
- * them providing one substring of the complete string
- * class's value.
- *
- * @param class Beginning string class
- * @param data User data
- * @returns #BT_BFCR_STATUS_OK or
- * #BT_BFCR_STATUS_ERROR
- */
- enum bt_bfcr_status (*string_begin)(struct ctf_field_class *cls, void *data);
-
- /**
- * Called when a string class's substring is decoded
- * (between a call to bt_bfcr_cbs::classes::string_begin()
- * and a call to bt_bfcr_cbs::classes::string_end()).
- *
- * @param value String value (\em not null-terminated)
- * @param len String value length
- * @param class String class
- * @param data User data
- * @returns #BT_BFCR_STATUS_OK or
- * #BT_BFCR_STATUS_ERROR
- */
- enum bt_bfcr_status (*string)(const char *value, size_t len, struct ctf_field_class *cls,
- void *data);
-
- /**
- * Called when a string class ends.
- *
- * @param class Ending string class
- * @param data User data
- * @returns #BT_BFCR_STATUS_OK or
- * #BT_BFCR_STATUS_ERROR
- */
- enum bt_bfcr_status (*string_end)(struct ctf_field_class *cls, void *data);
-
- /**
- * Called when a compound class begins.
- *
- * All the following class callback function calls will
- * signal sequential elements of this compound class,
- * until the next corresponding
- * bt_bfcr_cbs::classes::compound_end() is called.
- *
- * If \p class is a variant class, then only one class
- * callback function call will follow before the call to
- * bt_bfcr_cbs::classes::compound_end(). This single
- * call indicates the selected class of this variant
- * class.
- *
- * @param class Beginning compound class
- * @param data User data
- * @returns #BT_BFCR_STATUS_OK or
- * #BT_BFCR_STATUS_ERROR
- */
- enum bt_bfcr_status (*compound_begin)(struct ctf_field_class *cls, void *data);
-
- /**
- * Called when a compound class ends.
- *
- * @param class Ending compound class
- * @param data User data
- * @returns #BT_BFCR_STATUS_OK or
- * #BT_BFCR_STATUS_ERROR
- */
- enum bt_bfcr_status (*compound_end)(struct ctf_field_class *cls, void *data);
- } classes;
-
- /**
- * Query callback functions are used when the class reader needs
- * dynamic information, i.e. a sequence class's current length
- * or a variant class's current selected class.
- *
- * Both functions need to be set unless it is known that no
- * sequences or variants will have to be decoded.
- */
- struct
- {
- /**
- * Called to query the current length of a given sequence
- * class.
- *
- * @param class Sequence class
- * @param data User data
- * @returns Sequence length or
- * #BT_BFCR_STATUS_ERROR on error
- */
- int64_t (*get_sequence_length)(struct ctf_field_class *cls, void *data);
-
- /**
- * Called to query the current selected class of a given
- * variant class.
- *
- * @param class Variant class
- * @param data User data
- * @returns Current selected class (owned by
- * this) or \c NULL on error
- */
- struct ctf_field_class *(*borrow_variant_selected_field_class)(struct ctf_field_class *cls,
- void *data);
- } query;
-};
-
-/**
- * Creates a CTF binary class reader.
- *
- * @param cbs User callback functions
- * @param data User data (passed to user callback functions)
- * @returns New binary class reader on success, or \c NULL on error
- */
-struct bt_bfcr *bt_bfcr_create(struct bt_bfcr_cbs cbs, void *data, bt_logging_level log_level,
- bt_self_component *self_comp);
-
-/**
- * Destroys a CTF binary class reader, freeing all internal resources.
- *
- * @param bfcr Binary class reader
- */
-void bt_bfcr_destroy(struct bt_bfcr *bfcr);
-
-/**
- * Decodes a given CTF class from a buffer of bytes.
- *
- * The number of \em bits consumed by this function is returned.
- *
- * The \p status output parameter is where a status is written, amongst
- * the following:
- *
- * - <b>#BT_BFCR_STATUS_OK</b>: Decoding is done.
- * - <b>#BT_BFCR_STATUS_EOF</b>: The end of the buffer was reached,
- * but more data is needed to finish the decoding process of the
- * requested class. The user needs to call bt_bfcr_continue()
- * as long as #BT_BFCR_STATUS_EOF is returned to complete the
- * decoding process of the original class.
- * - <b>#BT_BFCR_STATUS_INVAL</b>: Invalid argument.
- * - <b>#BT_BFCR_STATUS_ERROR</b>: General error.
- *
- * Calling this function resets the class reader's internal state. If
- * #BT_BFCR_STATUS_EOF is returned, bt_bfcr_continue() needs to
- * be called next, \em not bt_bfcr_decode().
- *
- * @param bfcr Binary class reader
- * @param class Field class to decode
- * @param buf Buffer
- * @param offset Offset of first bit from \p buf (bits)
- * @param packet_offset Offset of \p offset within the CTF
- * binary packet containing \p class (bits)
- * @param sz Size of buffer in bytes (from \p buf)
- * @param status Returned status (see description above)
- * @returns Number of consumed bits
- */
-size_t bt_bfcr_start(struct bt_bfcr *bfcr, struct ctf_field_class *cls, const uint8_t *buf,
- size_t offset, size_t packet_offset, size_t sz, enum bt_bfcr_status *status);
-
-/**
- * Continues the decoding process a given CTF class.
- *
- * The number of bits consumed by this function is returned.
- *
- * The \p status output parameter is where a status is placed, amongst
- * the following:
- *
- * - <b>#BT_BFCR_STATUS_OK</b>: decoding is done.
- * - <b>#BT_BFCR_STATUS_EOF</b>: the end of the buffer was reached,
- * but more data is needed to finish the decoding process of the
- * requested class. The user needs to call bt_bfcr_continue()
- * as long as #BT_BFCR_STATUS_EOF is returned to complete the
- * decoding process of the original class.
- * - <b>#BT_BFCR_STATUS_INVAL</b>: invalid argument.
- * - <b>#BT_BFCR_STATUS_ERROR</b>: general error.
- *
- * @param bfcr Binary class reader
- * @param buf Buffer
- * @param sz Size of buffer in bytes (from \p offset)
- * @param status Returned status (see description above)
- * @returns Number of consumed bits
- */
-size_t bt_bfcr_continue(struct bt_bfcr *bfcr, const uint8_t *buf, size_t sz,
- enum bt_bfcr_status *status);
-
-void bt_bfcr_set_unsigned_int_cb(struct bt_bfcr *bfcr, bt_bfcr_unsigned_int_cb_func cb);
-
-static inline const char *bt_bfcr_status_string(enum bt_bfcr_status status)
-{
- switch (status) {
- case BT_BFCR_STATUS_ENOMEM:
- return "ENOMEM";
- case BT_BFCR_STATUS_EOF:
- return "EOF";
- case BT_BFCR_STATUS_INVAL:
- return "INVAL";
- case BT_BFCR_STATUS_ERROR:
- return "ERROR";
- case BT_BFCR_STATUS_OK:
- return "OK";
- }
-
- bt_common_abort();
-}
-
-#endif /* CTF_BFCR_H */
projects / babeltrace.git / blobdiff