+static void init_trace_collection(struct trace_collection *tc)
+{
+ tc->array = g_ptr_array_sized_new(DEFAULT_FILE_ARRAY_SIZE);
+ tc->clocks = g_hash_table_new(g_direct_hash, g_direct_equal);
+}
+
+/*
+ * finalize_trace_collection() closes the opened traces for read
+ * and free the memory allocated for trace collection
+ */
+static void finalize_trace_collection(struct trace_collection *tc)
+{
+ int i;
+
+ for (i = 0; i < tc->array->len; i++) {
+ struct trace_descriptor *temp =
+ g_ptr_array_index(tc->array, i);
+ fmt_read->close_trace(temp);
+ }
+ g_ptr_array_free(tc->array, TRUE);
+ g_hash_table_destroy(tc->clocks);
+}
+
+struct clock_match {
+ GHashTable *clocks;
+ struct ctf_clock *clock_match;
+ struct trace_collection *tc;
+};
+
+static void check_clock_match(gpointer key, gpointer value, gpointer user_data)
+{
+ struct clock_match *match = user_data;
+ struct ctf_clock *clock_a = value, *clock_b;
+
+ if (clock_a->uuid != 0) {
+ /*
+ * Lookup the the trace clocks into the collection
+ * clocks.
+ */
+ clock_b = g_hash_table_lookup(match->clocks,
+ (gpointer) (unsigned long) clock_a->uuid);
+ if (clock_b) {
+ match->clock_match = clock_b;
+ return;
+ }
+ } else if (clock_a->absolute) {
+ /*
+ * Absolute time references, such as NTP, are looked up
+ * by clock name.
+ */
+ clock_b = g_hash_table_lookup(match->clocks,
+ (gpointer) (unsigned long) clock_a->name);
+ if (clock_b) {
+ match->clock_match = clock_b;
+ return;
+ }
+ }
+}
+
+static void clock_add(gpointer key, gpointer value, gpointer user_data)
+{
+ struct clock_match *clock_match = user_data;
+ GHashTable *tc_clocks = clock_match->clocks;
+ struct ctf_clock *t_clock = value;
+ GQuark v;
+
+ if (t_clock->absolute)
+ v = t_clock->name;
+ else
+ v = t_clock->uuid;
+ if (v) {
+ struct ctf_clock *tc_clock;
+
+ tc_clock = g_hash_table_lookup(tc_clocks,
+ (gpointer) (unsigned long) v);
+ if (!tc_clock) {
+ /*
+ * For now, we only support CTF that has one
+ * single clock.
+ */
+ if (g_hash_table_size(tc_clocks) > 0) {
+ fprintf(stderr, "[error] Only CTF traces with a single clock description are supported by this babeltrace version.\n");
+ }
+ if (!clock_match->tc->single_clock) {
+ clock_match->tc->single_clock = value;
+ }
+ g_hash_table_insert(tc_clocks,
+ (gpointer) (unsigned long) v,
+ value);
+ } else {
+ int64_t diff_ns;
+
+ /*
+ * Check that the offsets match. If not, warn
+ * the user that we do an arbitrary choice.
+ */
+ diff_ns = tc_clock->offset_s;
+ diff_ns -= t_clock->offset_s;
+ diff_ns *= 1000000000ULL;
+ diff_ns += tc_clock->offset;
+ diff_ns -= t_clock->offset;
+ printf_debug("Clock \"%s\" offset between traces has a delta of %" PRIu64 " ns.",
+ g_quark_to_string(tc_clock->name),
+ diff_ns < 0 ? -diff_ns : diff_ns);
+ if (diff_ns > 10000) {
+ fprintf(stderr, "[warning] Clock \"%s\" offset differs between traces (delta %" PRIu64 " ns). Choosing one arbitrarily.\n",
+ g_quark_to_string(tc_clock->name),
+ diff_ns < 0 ? -diff_ns : diff_ns);
+ }
+ }
+ }
+}
+
+/*
+ * Whenever we add a trace to the trace collection, check that we can
+ * correlate this trace with at least one other clock in the trace.
+ */
+static int trace_collection_add(struct trace_collection *tc,
+ struct trace_descriptor *td)
+{
+ struct ctf_trace *trace = container_of(td, struct ctf_trace, parent);
+
+ g_ptr_array_add(tc->array, td);
+ trace->collection = tc;
+
+ if (tc->array->len > 1) {
+ struct clock_match clock_match = {
+ .clocks = tc->clocks,
+ .clock_match = NULL,
+ .tc = NULL,
+ };
+
+ /*
+ * With two or more traces, we need correlation info
+ * avalable.
+ */
+ g_hash_table_foreach(trace->clocks,
+ check_clock_match,
+ &clock_match);
+ if (!clock_match.clock_match) {
+ fprintf(stderr, "[error] No clocks can be correlated and multiple traces are added to the collection.\n");
+ goto error;
+ }
+ }
+
+ {
+ struct clock_match clock_match = {
+ .clocks = tc->clocks,
+ .clock_match = NULL,
+ .tc = tc,
+ };
+
+ /*
+ * Add each clock from the trace clocks into the trace
+ * collection clocks.
+ */
+ g_hash_table_foreach(trace->clocks,
+ clock_add,
+ &clock_match);
+ }
+ return 0;
+error:
+ return -EPERM;
+}
+
+int convert_trace(struct trace_descriptor *td_write,
+ struct bt_context *ctx)
+{
+ struct babeltrace_iter *iter;
+ struct ctf_stream *stream;
+ struct ctf_stream_event *event;
+ struct ctf_text_stream_pos *sout;
+ struct trace_collection_pos begin_pos;
+ int ret;
+
+ sout = container_of(td_write, struct ctf_text_stream_pos,
+ trace_descriptor);
+
+ begin_pos.type = BT_SEEK_BEGIN;
+ iter = babeltrace_iter_create(ctx, &begin_pos, NULL);
+ if (!iter) {
+ ret = -1;
+ goto error_iter;
+ }
+ while (babeltrace_iter_read_event(iter, &stream, &event) == 0) {
+ ret = sout->parent.event_cb(&sout->parent, stream);
+ if (ret) {
+ fprintf(stderr, "[error] Writing event failed.\n");
+ goto end;
+ }
+ ret = babeltrace_iter_next(iter);
+ if (ret < 0)
+ goto end;
+ }
+ ret = 0;
+
+end:
+ babeltrace_iter_destroy(iter);
+error_iter:
+ return ret;
+}
+
+
+/*
+ * traverse_dir() is the callback functiion for File Tree Walk (nftw).
+ * it receives the path of the current entry (file, dir, link..etc) with
+ * a flag to indicate the type of the entry.
+ * if the entry being visited is a directory and contains a metadata file,
+ * then open it for reading and save a trace_descriptor to that directory
+ * in the read trace collection.
+ */
+static int traverse_dir(const char *fpath, const struct stat *sb,
+ int tflag, struct FTW *ftwbuf)
+{
+ int dirfd;
+ int fd;
+ struct trace_descriptor *td_read;
+ int ret;
+
+ if (tflag != FTW_D)
+ return 0;
+ dirfd = open(fpath, 0);
+ if (dirfd < 0) {
+ fprintf(stderr, "[error] unable to open trace "
+ "directory file descriptor.\n");
+ return -1;
+ }
+ fd = openat(dirfd, "metadata", O_RDONLY);
+ if (fd < 0) {
+ close(dirfd);
+ } else {
+ close(fd);
+ close(dirfd);
+ td_read = fmt_read->open_trace(opt_input_path,
+ fpath, O_RDONLY, ctf_move_pos_slow,
+ NULL);
+ if (!td_read) {
+ fprintf(stderr, "Error opening trace \"%s\" "
+ "for reading.\n\n", fpath);
+ return -1; /* error */
+ }
+ ret = trace_collection_add(&trace_collection_read, td_read);
+ if (ret) {
+ return -1;
+ }
+ }
+ return 0; /* success */
+}
+