-/*
- * Open index file using a given path, channel name and tracefile count.
- *
- * Return allocated struct lttng_index_file, NULL on error.
- */
-struct lttng_index_file *lttng_index_file_open(const char *path_name,
- const char *channel_name, uint64_t tracefile_count,
- uint64_t tracefile_count_current)
-{
- struct lttng_index_file *index_file;
- int ret, read_fd;
- ssize_t read_len;
- char fullpath[PATH_MAX];
- struct ctf_packet_index_file_hdr hdr;
- uint32_t major, minor, element_len;
-
- assert(path_name);
- assert(channel_name);
-
- index_file = zmalloc(sizeof(*index_file));
- if (!index_file) {
- PERROR("allocating lttng_index_file");
- goto error;
- }
-
- if (tracefile_count > 0) {
- ret = snprintf(fullpath, sizeof(fullpath), "%s/" DEFAULT_INDEX_DIR "/%s_%"
- PRIu64 DEFAULT_INDEX_FILE_SUFFIX, path_name,
- channel_name, tracefile_count_current);
- } else {
- ret = snprintf(fullpath, sizeof(fullpath), "%s/" DEFAULT_INDEX_DIR "/%s"
- DEFAULT_INDEX_FILE_SUFFIX, path_name, channel_name);
- }
- if (ret < 0) {
- PERROR("snprintf index path");
- goto error;
- }
-
- DBG("Index opening file %s in read only", fullpath);
- read_fd = open(fullpath, O_RDONLY);
- if (read_fd < 0) {
- PERROR("opening index in read-only");
- goto error;
- }
-
- read_len = lttng_read(read_fd, &hdr, sizeof(hdr));
- if (read_len < 0) {
- PERROR("Reading index header");
- goto error_close;
- }
-
- if (be32toh(hdr.magic) != CTF_INDEX_MAGIC) {
- ERR("Invalid header magic");
- goto error_close;
- }
- major = be32toh(hdr.index_major);
- minor = be32toh(hdr.index_minor);
- element_len = be32toh(hdr.packet_index_len);
-
- if (major != CTF_INDEX_MAJOR) {
- ERR("Invalid header version");
- goto error_close;
- }
- if (element_len > sizeof(struct ctf_packet_index)) {
- ERR("Index element length too long");
- goto error_close;
- }
-
- index_file->fd = read_fd;
- index_file->major = major;
- index_file->minor = minor;
- index_file->element_len = element_len;
- urcu_ref_init(&index_file->ref);
-
- return index_file;
-
-error_close:
- if (read_fd >= 0) {
- int close_ret;
-
- close_ret = close(read_fd);
- if (close_ret < 0) {
- PERROR("close read fd %d", read_fd);
- }
- }
-
-error:
- free(index_file);
- return NULL;
-}
-