fs-sink: handle trace name

Now the fs-sink uses the trace name to create the output path.
The trace name is appended after the path argument passed on the command
line.
If the resulting path exists, the plugin increments a numerical suffix
until it finds one or reaches INT_MAX.

The trace name is refused if it is ".." or contains "../".

Signed-off-by: Julien Desfossez <jdesfossez@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>

diff --git a/plugins/ctf/fs-sink/write.c b/plugins/ctf/fs-sink/write.c
index 305638cbbd4dd0a68a361ead7fb866124f882b50..3ac1b6f2fcca8f88f16ede98b677340586f1c559 100644 (file)
--- a/plugins/ctf/fs-sink/write.c
+++ b/plugins/ctf/fs-sink/write.c
@@ -147,6 +147,61 @@ enum fs_writer_stream_state *insert_new_stream_state(
        return v;
 }
 
+static
+int make_trace_path(struct writer_component *writer_component,
+               struct bt_ctf_trace *trace, char *trace_path)
+{
+       int ret;
+       const char *trace_name;
+
+       trace_name = bt_ctf_trace_get_name(trace);
+       if (!trace_name) {
+               trace_name = writer_component->trace_name_base->str;
+       }
+       /* XXX: we might have to skip the first level, TBD. */
+
+       /* Sanitize the trace name. */
+       if (strlen(trace_name) == 2 && !strcmp(trace_name, "..")) {
+               fprintf(writer_component->err, "[error] Trace name cannot "
+                               "be \"..\"\n");
+               goto error;
+       }
+
+       if (strstr(trace_name, "../")) {
+               fprintf(writer_component->err, "[error] Trace name cannot "
+                               "contain \"../\", received \"%s\"\n",
+                               trace_name);
+               goto error;
+
+       }
+
+       snprintf(trace_path, PATH_MAX, "%s/%s",
+                       writer_component->base_path->str,
+                       trace_name);
+       if (g_file_test(trace_path, G_FILE_TEST_EXISTS)) {
+               int i = 0;
+               do {
+                       snprintf(trace_path, PATH_MAX, "%s/%s-%d",
+                                       writer_component->base_path->str,
+                                       trace_name, ++i);
+               } while (g_file_test(trace_path, G_FILE_TEST_EXISTS) && i < INT_MAX);
+               if (i == INT_MAX) {
+                       fprintf(writer_component->err, "[error] Unable to find "
+                                       "a unique trace path\n");
+                       goto error;
+               }
+       }
+
+       ret = 0;
+
+       goto end;
+
+error:
+       ret = -1;
+end:
+       return ret;
+}
+
 static
 struct fs_writer *insert_new_writer(
                struct writer_component *writer_component,
@@ -154,20 +209,22 @@ struct fs_writer *insert_new_writer(
 {
        struct bt_ctf_writer *ctf_writer = NULL;
        struct bt_ctf_trace *writer_trace = NULL;
-       char trace_name[PATH_MAX];
+       char trace_path[PATH_MAX];
        enum bt_component_status ret;
        struct bt_ctf_stream *stream = NULL;
        struct fs_writer *fs_writer = NULL;
        int nr_stream, i;
 
-       /* FIXME: replace with trace name when it will work. */
-       snprintf(trace_name, PATH_MAX, "%s/%s_%03d",
-                       writer_component->base_path->str,
-                       writer_component->trace_name_base->str,
-                       writer_component->trace_id++);
-       printf_verbose("CTF-Writer creating trace in %s\n", trace_name);
+       ret = make_trace_path(writer_component, trace, trace_path);
+       if (ret) {
+               fprintf(writer_component->err, "[error] %s in %s:%d\n",
+                               __func__, __FILE__, __LINE__);
+               goto error;
+       }
+
+       printf("ctf.fs sink creating trace in %s\n", trace_path);
 
-       ctf_writer = bt_ctf_writer_create(trace_name);
+       ctf_writer = bt_ctf_writer_create(trace_path);
        if (!ctf_writer) {
                fprintf(writer_component->err, "[error] %s in %s:%d\n",
                                __func__, __FILE__, __LINE__);