[lttng-tools.git] / src / common / index / index.c

/*
 * Copyright (C) 2013 - Julien Desfossez <jdesfossez@efficios.com>
 *                      David Goulet <dgoulet@efficios.com>
 *               2016 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License, version 2 only, as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 51
 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#define _LGPL_SOURCE
#include <assert.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <fcntl.h>

#include <lttng/constant.h>
#include <common/common.h>
#include <common/defaults.h>
#include <common/compat/endian.h>
#include <common/utils.h>

#include "index.h"

#define WRITE_FILE_FLAGS	(O_WRONLY | O_CREAT | O_TRUNC)
#define READ_ONLY_FILE_FLAGS	O_RDONLY

static struct lttng_index_file *_lttng_index_file_create_from_trace_chunk(
		struct lttng_trace_chunk *chunk,
		const char *channel_path, const char *stream_name,
		uint64_t stream_file_size, uint64_t stream_file_index,
		uint32_t index_major, uint32_t index_minor,
		bool unlink_existing_file,
		int flags)
{
	struct lttng_index_file *index_file;
	enum lttng_trace_chunk_status chunk_status;
	int ret, fd = -1;
	ssize_t size_ret;
	struct ctf_packet_index_file_hdr hdr;
	char index_directory_path[LTTNG_PATH_MAX];
	char index_file_path[LTTNG_PATH_MAX];
	const mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP;
	const bool acquired_reference = lttng_trace_chunk_get(chunk);

	assert(acquired_reference);

	index_file = zmalloc(sizeof(*index_file));
	if (!index_file) {
		PERROR("Failed to allocate lttng_index_file");
		goto error;
	}

	index_file->trace_chunk = chunk;
	ret = snprintf(index_directory_path, sizeof(index_directory_path),
			"%s/" DEFAULT_INDEX_DIR, channel_path);
	if (ret < 0 || ret >= sizeof(index_directory_path)) {
		ERR("Failed to format index directory path");
		goto error;
	}

	ret = utils_stream_file_path(index_directory_path, stream_name,
			stream_file_size, stream_file_index,
			DEFAULT_INDEX_FILE_SUFFIX,
			index_file_path, sizeof(index_file_path));
	if (ret) {
		goto error;
	}

	if (unlink_existing_file) {
		/*
		 * For tracefile rotation. We need to unlink the old
		 * file if present to synchronize with the tail of the
		 * live viewer which could be working on this same file.
		 * By doing so, any reference to the old index file
		 * stays valid even if we re-create a new file with the
		 * same name afterwards.
		 */
		chunk_status = lttng_trace_chunk_unlink_file(
				chunk, index_file_path);
		if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK &&
				!(chunk_status == LTTNG_TRACE_CHUNK_STATUS_ERROR &&
						errno == ENOENT)) {
			goto error;
		}
	}

	chunk_status = lttng_trace_chunk_open_file(chunk, index_file_path,
			flags, mode, &fd);
	if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) {
		goto error;
	}

	if (flags == WRITE_FILE_FLAGS) {
		ctf_packet_index_file_hdr_init(&hdr, index_major, index_minor);
		size_ret = lttng_write(fd, &hdr, sizeof(hdr));
		if (size_ret < sizeof(hdr)) {
			PERROR("Failed to write index header");
			goto error;
		}
		index_file->element_len = ctf_packet_index_len(index_major, index_minor);
	} else {
		uint32_t element_len;

		size_ret = lttng_read(fd, &hdr, sizeof(hdr));
		if (size_ret < 0) {
			PERROR("Failed to read index header");
			goto error;
		}
		if (be32toh(hdr.magic) != CTF_INDEX_MAGIC) {
			ERR("Invalid header magic");
			goto error;
		}
		if (index_major != be32toh(hdr.index_major)) {
			ERR("Index major number mismatch: %u, expect %u",
				be32toh(hdr.index_major), index_major);
			goto error;
		}
		if (index_minor != be32toh(hdr.index_minor)) {
			ERR("Index minor number mismatch: %u, expect %u",
				be32toh(hdr.index_minor), index_minor);
			goto error;
		}
		element_len = be32toh(hdr.packet_index_len);
		if (element_len > sizeof(struct ctf_packet_index)) {
			ERR("Index element length too long");
			goto error;
		}
		index_file->element_len = element_len;
	}
	index_file->fd = fd;
	index_file->major = index_major;
	index_file->minor = index_minor;
	urcu_ref_init(&index_file->ref);

	return index_file;

error:
	if (fd >= 0) {
		ret = close(fd);
		if (ret < 0) {
			PERROR("Failed to close file descriptor of index file");
		}
	}
	lttng_trace_chunk_put(chunk);
	free(index_file);
	return NULL;
}

struct lttng_index_file *lttng_index_file_create_from_trace_chunk(
		struct lttng_trace_chunk *chunk,
		const char *channel_path, const char *stream_name,
		uint64_t stream_file_size, uint64_t stream_file_index,
		uint32_t index_major, uint32_t index_minor,
		bool unlink_existing_file)
{
	return _lttng_index_file_create_from_trace_chunk(chunk, channel_path,
			stream_name, stream_file_size, stream_file_index,
			index_major, index_minor, unlink_existing_file,
			WRITE_FILE_FLAGS);
}

struct lttng_index_file *lttng_index_file_create_from_trace_chunk_read_only(
		struct lttng_trace_chunk *chunk,
		const char *channel_path, const char *stream_name,
		uint64_t stream_file_size, uint64_t stream_file_index,
		uint32_t index_major, uint32_t index_minor)
{
	return _lttng_index_file_create_from_trace_chunk(chunk, channel_path,
			stream_name, stream_file_size, stream_file_index,
			index_major, index_minor, false,
			READ_ONLY_FILE_FLAGS);
}

/*
 * Write index values to the given index file.
 *
 * Return 0 on success, -1 on error.
 */
int lttng_index_file_write(const struct lttng_index_file *index_file,
		const struct ctf_packet_index *element)
{
	int fd;
	size_t len;
	ssize_t ret;

	assert(index_file);
	assert(element);

	fd = index_file->fd;
	len = index_file->element_len;

	if (fd < 0) {
		goto error;
	}

	ret = lttng_write(fd, element, len);
	if (ret < len) {
		PERROR("writing index file");
		goto error;
	}
	return 0;

error:
	return -1;
}

/*
 * Read index values from the given index file.
 *
 * Return 0 on success, -1 on error.
 */
int lttng_index_file_read(const struct lttng_index_file *index_file,
		struct ctf_packet_index *element)
{
	ssize_t ret;
	int fd = index_file->fd;
	size_t len = index_file->element_len;

	assert(element);

	if (fd < 0) {
		goto error;
	}

	ret = lttng_read(fd, element, len);
	if (ret < 0) {
		PERROR("read index file");
		goto error;
	}
	if (ret < len) {
		ERR("lttng_read expected %zu, returned %zd", len, ret);
		goto error;
	}
	return 0;

error:
	return -1;
}

void lttng_index_file_get(struct lttng_index_file *index_file)
{
	urcu_ref_get(&index_file->ref);
}

static void lttng_index_file_release(struct urcu_ref *ref)
{
	struct lttng_index_file *index_file = caa_container_of(ref,
			struct lttng_index_file, ref);

	if (close(index_file->fd)) {
		PERROR("close index fd");
	}
	lttng_trace_chunk_put(index_file->trace_chunk);
	free(index_file);
}

void lttng_index_file_put(struct lttng_index_file *index_file)
{
	urcu_ref_put(&index_file->ref, lttng_index_file_release);
}
Commit	Line	Data
309167d2 JD	1	/*
	2	* Copyright (C) 2013 - Julien Desfossez <jdesfossez@efficios.com>
	3	* David Goulet <dgoulet@efficios.com>
f8f3885c	4	* 2016 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
309167d2 JD	5	*
	6	* This program is free software; you can redistribute it and/or modify it
	7	* under the terms of the GNU General Public License, version 2 only, as
	8	* published by the Free Software Foundation.
	9	*
	10	* This program is distributed in the hope that it will be useful, but WITHOUT
	11	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	12	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	13	* more details.
	14	*
	15	* You should have received a copy of the GNU General Public License along with
	16	* this program; if not, write to the Free Software Foundation, Inc., 51
	17	* Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
	18	*/
	19
6c1c0768	20	#define _LGPL_SOURCE
309167d2	21	#include <assert.h>
1c20f0e2	22	#include <sys/stat.h>
2f8f53af DG	23	#include <sys/types.h>
2f8f53af DG	24	#include <fcntl.h>
309167d2	25
d2956687	26	#include <lttng/constant.h>
309167d2 JD	27	#include <common/common.h>
309167d2 JD	28	#include <common/defaults.h>
f263b7fd	29	#include <common/compat/endian.h>
309167d2 JD	30	#include <common/utils.h>
	31
	32	#include "index.h"
	33
2ef0da38	34	#define WRITE_FILE_FLAGS (O_WRONLY \| O_CREAT \| O_TRUNC)
ebb29c10 JG	35	#define READ_ONLY_FILE_FLAGS O_RDONLY
	36
	37	static struct lttng_index_file *_lttng_index_file_create_from_trace_chunk(
d2956687	38	struct lttng_trace_chunk *chunk,
ebb29c10	39	const char channel_path, const char stream_name,
c35f9726	40	uint64_t stream_file_size, uint64_t stream_file_index,
d2956687	41	uint32_t index_major, uint32_t index_minor,
ebb29c10 JG	42	bool unlink_existing_file,
ebb29c10 JG	43	int flags)
d2956687 JG	44	{
	45	struct lttng_index_file *index_file;
	46	enum lttng_trace_chunk_status chunk_status;
	47	int ret, fd = -1;
	48	ssize_t size_ret;
	49	struct ctf_packet_index_file_hdr hdr;
	50	char index_directory_path[LTTNG_PATH_MAX];
	51	char index_file_path[LTTNG_PATH_MAX];
d2956687	52	const mode_t mode = S_IRUSR \| S_IWUSR \| S_IRGRP \| S_IWGRP;
ebb29c10	53	const bool acquired_reference = lttng_trace_chunk_get(chunk);
c35f9726 JG	54
c35f9726 JG	55	assert(acquired_reference);
d2956687 JG	56
	57	index_file = zmalloc(sizeof(*index_file));
	58	if (!index_file) {
	59	PERROR("Failed to allocate lttng_index_file");
	60	goto error;
	61	}
	62
c35f9726	63	index_file->trace_chunk = chunk;
d2956687 JG	64	ret = snprintf(index_directory_path, sizeof(index_directory_path),
	65	"%s/" DEFAULT_INDEX_DIR, channel_path);
	66	if (ret < 0 \|\| ret >= sizeof(index_directory_path)) {
	67	ERR("Failed to format index directory path");
	68	goto error;
	69	}
	70
	71	ret = utils_stream_file_path(index_directory_path, stream_name,
c35f9726	72	stream_file_size, stream_file_index,
d2956687 JG	73	DEFAULT_INDEX_FILE_SUFFIX,
	74	index_file_path, sizeof(index_file_path));
	75	if (ret) {
	76	goto error;
	77	}
	78
	79	if (unlink_existing_file) {
	80	/*
	81	* For tracefile rotation. We need to unlink the old
	82	* file if present to synchronize with the tail of the
	83	* live viewer which could be working on this same file.
	84	* By doing so, any reference to the old index file
	85	* stays valid even if we re-create a new file with the
	86	* same name afterwards.
	87	*/
348a81dc JG	88	chunk_status = lttng_trace_chunk_unlink_file(
	89	chunk, index_file_path);
	90	if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK &&
	91	!(chunk_status == LTTNG_TRACE_CHUNK_STATUS_ERROR &&
	92	errno == ENOENT)) {
d2956687 JG	93	goto error;
d2956687 JG	94	}
348a81dc	95	}
d2956687 JG	96
	97	chunk_status = lttng_trace_chunk_open_file(chunk, index_file_path,
	98	flags, mode, &fd);
	99	if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) {
	100	goto error;
	101	}
	102
84546278 MD	103	if (flags == WRITE_FILE_FLAGS) {
	104	ctf_packet_index_file_hdr_init(&hdr, index_major, index_minor);
	105	size_ret = lttng_write(fd, &hdr, sizeof(hdr));
	106	if (size_ret < sizeof(hdr)) {
	107	PERROR("Failed to write index header");
	108	goto error;
	109	}
	110	index_file->element_len = ctf_packet_index_len(index_major, index_minor);
	111	} else {
	112	uint32_t element_len;
	113
	114	size_ret = lttng_read(fd, &hdr, sizeof(hdr));
	115	if (size_ret < 0) {
	116	PERROR("Failed to read index header");
	117	goto error;
	118	}
	119	if (be32toh(hdr.magic) != CTF_INDEX_MAGIC) {
	120	ERR("Invalid header magic");
	121	goto error;
	122	}
	123	if (index_major != be32toh(hdr.index_major)) {
	124	ERR("Index major number mismatch: %u, expect %u",
	125	be32toh(hdr.index_major), index_major);
	126	goto error;
	127	}
	128	if (index_minor != be32toh(hdr.index_minor)) {
	129	ERR("Index minor number mismatch: %u, expect %u",
	130	be32toh(hdr.index_minor), index_minor);
	131	goto error;
	132	}
	133	element_len = be32toh(hdr.packet_index_len);
	134	if (element_len > sizeof(struct ctf_packet_index)) {
	135	ERR("Index element length too long");
	136	goto error;
	137	}
	138	index_file->element_len = element_len;
d2956687 JG	139	}
	140	index_file->fd = fd;
	141	index_file->major = index_major;
	142	index_file->minor = index_minor;
d2956687 JG	143	urcu_ref_init(&index_file->ref);
	144
	145	return index_file;
	146
	147	error:
	148	if (fd >= 0) {
	149	ret = close(fd);
	150	if (ret < 0) {
	151	PERROR("Failed to close file descriptor of index file");
	152	}
	153	}
307db950	154	lttng_trace_chunk_put(chunk);
d2956687 JG	155	free(index_file);
	156	return NULL;
	157	}
	158
ebb29c10 JG	159	struct lttng_index_file *lttng_index_file_create_from_trace_chunk(
	160	struct lttng_trace_chunk *chunk,
	161	const char channel_path, const char stream_name,
	162	uint64_t stream_file_size, uint64_t stream_file_index,
	163	uint32_t index_major, uint32_t index_minor,
	164	bool unlink_existing_file)
	165	{
	166	return _lttng_index_file_create_from_trace_chunk(chunk, channel_path,
	167	stream_name, stream_file_size, stream_file_index,
	168	index_major, index_minor, unlink_existing_file,
	169	WRITE_FILE_FLAGS);
	170	}
	171
	172	struct lttng_index_file *lttng_index_file_create_from_trace_chunk_read_only(
	173	struct lttng_trace_chunk *chunk,
	174	const char channel_path, const char stream_name,
	175	uint64_t stream_file_size, uint64_t stream_file_index,
	176	uint32_t index_major, uint32_t index_minor)
	177	{
	178	return _lttng_index_file_create_from_trace_chunk(chunk, channel_path,
	179	stream_name, stream_file_size, stream_file_index,
	180	index_major, index_minor, false,
	181	READ_ONLY_FILE_FLAGS);
	182	}
	183
309167d2	184	/*
f8f3885c	185	* Write index values to the given index file.
309167d2	186	*
f8f3885c	187	* Return 0 on success, -1 on error.
309167d2	188	*/
f8f3885c MD	189	int lttng_index_file_write(const struct lttng_index_file *index_file,
f8f3885c MD	190	const struct ctf_packet_index *element)
309167d2	191	{
0b0ac4a9 JR	192	int fd;
0b0ac4a9 JR	193	size_t len;
6cd525e8	194	ssize_t ret;
309167d2	195
0b0ac4a9	196	assert(index_file);
f8f3885c	197	assert(element);
309167d2	198
0b0ac4a9 JR	199	fd = index_file->fd;
	200	len = index_file->element_len;
	201
183f6fa2	202	if (fd < 0) {
183f6fa2 DG	203	goto error;
	204	}
	205
f8f3885c	206	ret = lttng_write(fd, element, len);
6cd525e8	207	if (ret < len) {
309167d2	208	PERROR("writing index file");
f8f3885c MD	209	goto error;
	210	}
	211	return 0;
	212
	213	error:
	214	return -1;
	215	}
	216
	217	/*
	218	* Read index values from the given index file.
	219	*
	220	* Return 0 on success, -1 on error.
	221	*/
	222	int lttng_index_file_read(const struct lttng_index_file *index_file,
	223	struct ctf_packet_index *element)
	224	{
	225	ssize_t ret;
	226	int fd = index_file->fd;
	227	size_t len = index_file->element_len;
	228
	229	assert(element);
	230
	231	if (fd < 0) {
	232	goto error;
	233	}
	234
	235	ret = lttng_read(fd, element, len);
2239b15a	236	if (ret < 0) {
f8f3885c MD	237	PERROR("read index file");
f8f3885c MD	238	goto error;
309167d2	239	}
2239b15a MD	240	if (ret < len) {
	241	ERR("lttng_read expected %zu, returned %zd", len, ret);
	242	goto error;
	243	}
f8f3885c	244	return 0;
309167d2	245
183f6fa2	246	error:
f8f3885c	247	return -1;
309167d2	248	}
2f8f53af	249
f8f3885c MD	250	void lttng_index_file_get(struct lttng_index_file *index_file)
	251	{
	252	urcu_ref_get(&index_file->ref);
	253	}
	254
	255	static void lttng_index_file_release(struct urcu_ref *ref)
	256	{
	257	struct lttng_index_file *index_file = caa_container_of(ref,
	258	struct lttng_index_file, ref);
	259
	260	if (close(index_file->fd)) {
	261	PERROR("close index fd");
	262	}
c35f9726	263	lttng_trace_chunk_put(index_file->trace_chunk);
f8f3885c MD	264	free(index_file);
	265	}
	266
	267	void lttng_index_file_put(struct lttng_index_file *index_file)
	268	{
	269	urcu_ref_put(&index_file->ref, lttng_index_file_release);
2f8f53af	270	}