[babeltrace.git] / plugins / ctf / common / metadata / decoder.h

#ifndef _METADATA_DECODER_H
#define _METADATA_DECODER_H

/*
 * Copyright 2016-2017 - Philippe Proulx <pproulx@efficios.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 */

#include <stdint.h>

struct bt_ctf_trace;

/* A CTF metadata decoder object */
struct ctf_metadata_decoder;

/* CTF metadata decoder status */
enum ctf_metadata_decoder_status {
	CTF_METADATA_DECODER_STATUS_OK			= 0,
	CTF_METADATA_DECODER_STATUS_ERROR		= -1,
	CTF_METADATA_DECODER_STATUS_INCOMPLETE		= -2,
	CTF_METADATA_DECODER_STATUS_INVAL_VERSION	= -3,
	CTF_METADATA_DECODER_STATUS_IR_VISITOR_ERROR	= -4,
};

/*
 * Creates a CTF metadata decoder with `err` as the error stream (can
 * be `NULL` to disable error output). `clock_class_offset_ns` is an
 * offset to apply to the decoded clock classes's offsets. `name` is
 * this decoder's trace's name.
 *
 * Returns `NULL` on error.
 */
BT_HIDDEN
struct ctf_metadata_decoder *ctf_metadata_decoder_create(FILE *err,
		uint64_t clock_class_offset_ns, const char *name);

/*
 * Destroys a CTF metadata decoder that you created with
 * ctf_metadata_decoder_create().
 */
BT_HIDDEN
void ctf_metadata_decoder_destroy(
		struct ctf_metadata_decoder *metadata_decoder);

/*
 * Decodes a new chunk of CTF metadata.
 *
 * This function reads the metadata from the current position of `fp`
 * until the end of this file stream. If it finds new information (new
 * event class, new stream class, or new clock class), it appends this
 * information to the decoder's trace object (as returned by
 * ctf_metadata_get_trace()), or it creates this trace.
 *
 * The metadata can be packetized or not.
 *
 * The metadata chunk needs to be complete and scannable, that is,
 * zero or more complete top-level blocks. If it's incomplete, this
 * function returns `CTF_METADATA_DECODER_STATUS_INCOMPLETE`. If this
 * function returns `CTF_METADATA_DECODER_STATUS_INCOMPLETE`, then you
 * need to call it again with the same metadata and more to make it
 * complete. For example:
 *
 *     First call:  event { name = hell
 *     Second call: event { name = hello_world; ... };
 *
 * If the conversion from the metadata text to CTF IR objects fails,
 * this function returns `CTF_METADATA_DECODER_STATUS_IR_VISITOR_ERROR`.
 *
 * If everything goes as expected, this function returns
 * `CTF_METADATA_DECODER_STATUS_OK`.
 */
BT_HIDDEN
enum ctf_metadata_decoder_status ctf_metadata_decoder_decode(
		struct ctf_metadata_decoder *metadata_decoder, FILE *fp);

/*
 * Returns a new reference to the current CTF IR trace object which is
 * the result of the metadata decoding process.
 *
 * The trace object, once created, remains the same until you call
 * ctf_metadata_decoder_destroy().
 */
BT_HIDDEN
struct bt_ctf_trace *ctf_metadata_decoder_get_trace(
		struct ctf_metadata_decoder *metadata_decoder);

/*
 * Checks whether or not a given metadata file stream is packetized, and
 * if so, sets `*byte_order` to the byte order of the first packet.
 */
BT_HIDDEN
bool ctf_metadata_decoder_is_packetized(FILE *fp, int *byte_order);

/*
 * Decodes a packetized metadata file stream to a NULL-terminated
 * text buffer using the given byte order.
 */
BT_HIDDEN
int ctf_metadata_decoder_packetized_file_stream_to_buf(
		FILE *fp, char **buf, int byte_order);

#endif /* _METADATA_DECODER_H */
Commit	Line	Data
1e649dff PP	1	#ifndef _METADATA_DECODER_H
	2	#define _METADATA_DECODER_H
	3
	4	/*
	5	* Copyright 2016-2017 - Philippe Proulx <pproulx@efficios.com>
	6	*
	7	* Permission is hereby granted, free of charge, to any person obtaining a copy
	8	* of this software and associated documentation files (the "Software"), to deal
	9	* in the Software without restriction, including without limitation the rights
	10	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	11	* copies of the Software, and to permit persons to whom the Software is
	12	* furnished to do so, subject to the following conditions:
	13	*
	14	* The above copyright notice and this permission notice shall be included in
	15	* all copies or substantial portions of the Software.
	16	*/
	17
	18	#include <stdint.h>
	19
	20	struct bt_ctf_trace;
	21
	22	/* A CTF metadata decoder object */
	23	struct ctf_metadata_decoder;
	24
	25	/* CTF metadata decoder status */
	26	enum ctf_metadata_decoder_status {
	27	CTF_METADATA_DECODER_STATUS_OK = 0,
	28	CTF_METADATA_DECODER_STATUS_ERROR = -1,
	29	CTF_METADATA_DECODER_STATUS_INCOMPLETE = -2,
	30	CTF_METADATA_DECODER_STATUS_INVAL_VERSION = -3,
	31	CTF_METADATA_DECODER_STATUS_IR_VISITOR_ERROR = -4,
	32	};
	33
	34	/*
	35	* Creates a CTF metadata decoder with `err` as the error stream (can
	36	* be `NULL` to disable error output). `clock_class_offset_ns` is an
1a9f7075 PP	37	* offset to apply to the decoded clock classes's offsets. `name` is
1a9f7075 PP	38	* this decoder's trace's name.
1e649dff PP	39	*
	40	* Returns `NULL` on error.
	41	*/
	42	BT_HIDDEN
	43	struct ctf_metadata_decoder ctf_metadata_decoder_create(FILE err,
1a9f7075	44	uint64_t clock_class_offset_ns, const char *name);
1e649dff PP	45
	46	/*
	47	* Destroys a CTF metadata decoder that you created with
	48	* ctf_metadata_decoder_create().
	49	*/
	50	BT_HIDDEN
	51	void ctf_metadata_decoder_destroy(
	52	struct ctf_metadata_decoder *metadata_decoder);
	53
	54	/*
	55	* Decodes a new chunk of CTF metadata.
	56	*
	57	* This function reads the metadata from the current position of `fp`
	58	* until the end of this file stream. If it finds new information (new
	59	* event class, new stream class, or new clock class), it appends this
	60	* information to the decoder's trace object (as returned by
	61	* ctf_metadata_get_trace()), or it creates this trace.
	62	*
	63	* The metadata can be packetized or not.
	64	*
	65	* The metadata chunk needs to be complete and scannable, that is,
	66	* zero or more complete top-level blocks. If it's incomplete, this
	67	* function returns `CTF_METADATA_DECODER_STATUS_INCOMPLETE`. If this
	68	* function returns `CTF_METADATA_DECODER_STATUS_INCOMPLETE`, then you
	69	* need to call it again with the same metadata and more to make it
	70	* complete. For example:
	71	*
	72	* First call: event { name = hell
	73	* Second call: event { name = hello_world; ... };
	74	*
	75	* If the conversion from the metadata text to CTF IR objects fails,
	76	* this function returns `CTF_METADATA_DECODER_STATUS_IR_VISITOR_ERROR`.
	77	*
	78	* If everything goes as expected, this function returns
	79	* `CTF_METADATA_DECODER_STATUS_OK`.
	80	*/
	81	BT_HIDDEN
	82	enum ctf_metadata_decoder_status ctf_metadata_decoder_decode(
	83	struct ctf_metadata_decoder metadata_decoder, FILE fp);
	84
	85	/*
	86	* Returns a new reference to the current CTF IR trace object which is
	87	* the result of the metadata decoding process.
	88	*
	89	* The trace object, once created, remains the same until you call
	90	* ctf_metadata_decoder_destroy().
	91	*/
	92	BT_HIDDEN
	93	struct bt_ctf_trace *ctf_metadata_decoder_get_trace(
	94	struct ctf_metadata_decoder *metadata_decoder);
	95
	96	/*
	97	* Checks whether or not a given metadata file stream is packetized, and
	98	* if so, sets `*byte_order` to the byte order of the first packet.
	99	*/
	100	BT_HIDDEN
	101	bool ctf_metadata_decoder_is_packetized(FILE fp, int byte_order);
	102
	103	/*
	104	* Decodes a packetized metadata file stream to a NULL-terminated
	105	* text buffer using the given byte order.
	106	*/
	107	BT_HIDDEN
	108	int ctf_metadata_decoder_packetized_file_stream_to_buf(
109	FILE fp, char *buf, int byte_order);
110
111	#endif /* _METADATA_DECODER_H */