/*
* 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
* Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
-#define _GNU_SOURCE
+#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"
-/*
- * Create the index file associated with a trace file.
- *
- * Return fd on success, a negative value on error.
- */
-int index_create_file(char *path_name, char *stream_name, int uid, int gid,
- uint64_t size, uint64_t count)
+#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 lttng_packet_index_file_hdr hdr;
- char fullpath[PATH_MAX];
+ 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);
- ret = snprintf(fullpath, sizeof(fullpath), "%s/" DEFAULT_INDEX_DIR,
- path_name);
- if (ret < 0) {
- PERROR("snprintf index path");
+ assert(acquired_reference);
+
+ index_file = zmalloc(sizeof(*index_file));
+ if (!index_file) {
+ PERROR("Failed to allocate lttng_index_file");
goto error;
}
- /* Create index directory if necessary. */
- ret = run_as_mkdir(fullpath, S_IRWXU | S_IRWXG, uid, gid);
- if (ret < 0) {
- if (ret != -EEXIST) {
- ERR("Index trace directory creation 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;
}
}
- ret = utils_create_stream_file(fullpath, stream_name, size, count, uid,
- gid, DEFAULT_INDEX_FILE_SUFFIX);
- if (ret < 0) {
+ chunk_status = lttng_trace_chunk_open_file(chunk, index_file_path,
+ flags, mode, &fd);
+ if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) {
goto error;
}
- fd = ret;
- memcpy(hdr.magic, INDEX_MAGIC, sizeof(hdr.magic));
- hdr.index_major = htobe32(INDEX_MAJOR);
- hdr.index_minor = htobe32(INDEX_MINOR);
+ 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_write(fd, &hdr, sizeof(hdr));
- if (size_ret < sizeof(hdr)) {
- PERROR("write index header");
- ret = -1;
- goto error;
+ 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 fd;
+ return index_file;
error:
if (fd >= 0) {
- int close_ret;
-
- close_ret = close(fd);
- if (close_ret < 0) {
- PERROR("close index fd");
+ ret = close(fd);
+ if (ret < 0) {
+ PERROR("Failed to close file descriptor of index file");
}
}
- return ret;
+ 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 fd of size len.
+ * Write index values to the given index file.
*
- * Return "len" on success or else < len on error. errno contains error
- * details.
+ * Return 0 on success, -1 on error.
*/
-ssize_t index_write(int fd, struct lttng_packet_index *index, size_t len)
+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(fd >= 0);
- assert(index);
+ assert(index_file);
+ assert(element);
- ret = lttng_write(fd, index, len);
+ 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;
}
- return ret;
+ 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);
}