Add wildcard support

[lttng-ust.git] / liblttng-ust / lttng-ust-abi.c

diff --git a/liblttng-ust/lttng-ust-abi.c b/liblttng-ust/lttng-ust-abi.c
index 25f213bbc1ce1bf72fd09194459177f9bfce5064..716a2cc9d1a13efe8d8e943a6c41ad6c98395413 100644 (file)
--- a/liblttng-ust/lttng-ust-abi.c
+++ b/liblttng-ust/lttng-ust-abi.c
@@ -204,6 +204,7 @@ static const struct lttng_ust_objd_ops lttng_channel_ops;
 static const struct lttng_ust_objd_ops lttng_metadata_ops;
 static const struct lttng_ust_objd_ops lttng_event_ops;
 static const struct lttng_ust_objd_ops lttng_loglevel_ops;
+static const struct lttng_ust_objd_ops lttng_wildcard_ops;
 static const struct lttng_ust_objd_ops lib_ring_buffer_objd_ops;
 static const struct lttng_ust_objd_ops lttng_tracepoint_list_ops;
 
@@ -697,6 +698,44 @@ objd_error:
        return ret;
 }
 
+static
+int lttng_abi_create_wildcard(int channel_objd,
+                             struct lttng_ust_event *event_param)
+{
+       struct ltt_channel *channel = objd_private(channel_objd);
+       struct session_wildcard *wildcard;
+       int wildcard_objd, ret;
+
+       event_param->name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
+       wildcard_objd = objd_alloc(NULL, &lttng_wildcard_ops);
+       if (wildcard_objd < 0) {
+               ret = wildcard_objd;
+               goto objd_error;
+       }
+       /*
+        * We tolerate no failure path after wildcard creation. It will
+        * stay invariant for the rest of the session.
+        */
+       ret = ltt_wildcard_create(channel, event_param, &wildcard);
+       if (ret < 0) {
+               goto wildcard_error;
+       }
+       objd_set_private(wildcard_objd, wildcard);
+       /* The wildcard holds a reference on the channel */
+       objd_ref(channel_objd);
+       return wildcard_objd;
+
+wildcard_error:
+       {
+               int err;
+
+               err = lttng_ust_objd_unref(wildcard_objd);
+               assert(!err);
+       }
+objd_error:
+       return ret;
+}
+
 /**
  *     lttng_channel_cmd - lttng control through object descriptors
  *
@@ -740,7 +779,12 @@ long lttng_channel_cmd(int objd, unsigned int cmd, unsigned long arg)
                if (event_param->instrumentation == LTTNG_UST_TRACEPOINT_LOGLEVEL) {
                        return lttng_abi_create_loglevel(objd, event_param);
                } else {
-                       return lttng_abi_create_event(objd, event_param);
+                       if (event_param->name[strlen(event_param->name) - 1] == '*') {
+                               /* If ends with wildcard, create wildcard. */
+                               return lttng_abi_create_wildcard(objd, event_param);
+                       } else {
+                               return lttng_abi_create_event(objd, event_param);
+                       }
                }
        }
        case LTTNG_UST_CONTEXT:
@@ -1003,6 +1047,60 @@ static const struct lttng_ust_objd_ops lttng_loglevel_ops = {
        .cmd = lttng_loglevel_cmd,
 };
 
+/**
+ *     lttng_wildcard_cmd - lttng control through object descriptors
+ *
+ *     @objd: the object descriptor
+ *     @cmd: the command
+ *     @arg: command arg
+ *
+ *     This object descriptor implements lttng commands:
+ *     LTTNG_UST_CONTEXT
+ *             Prepend a context field to each record of events of this
+ *             wildcard.
+ *     LTTNG_UST_ENABLE
+ *             Enable recording for these wildcard events (weak enable)
+ *     LTTNG_UST_DISABLE
+ *             Disable recording for these wildcard events (strong disable)
+ */
+static
+long lttng_wildcard_cmd(int objd, unsigned int cmd, unsigned long arg)
+{
+       struct session_wildcard *wildcard = objd_private(objd);
+
+       switch (cmd) {
+       case LTTNG_UST_CONTEXT:
+               return -ENOSYS; /* not implemented yet */
+#if 0
+               return lttng_abi_add_context(objd,
+                               (struct lttng_ust_context *) arg,
+                               &wildcard->ctx, wildcard->chan->session);
+#endif
+       case LTTNG_UST_ENABLE:
+               return ltt_wildcard_enable(wildcard);
+       case LTTNG_UST_DISABLE:
+               return ltt_wildcard_disable(wildcard);
+       default:
+               return -EINVAL;
+       }
+}
+
+static
+int lttng_wildcard_release(int objd)
+{
+       struct session_wildcard *wildcard = objd_private(objd);
+
+       if (wildcard)
+               return lttng_ust_objd_unref(wildcard->chan->objd);
+       return 0;
+}
+
+/* TODO: filter control ioctl */
+static const struct lttng_ust_objd_ops lttng_wildcard_ops = {
+       .release = lttng_wildcard_release,
+       .cmd = lttng_wildcard_cmd,
+};
+
 void lttng_ust_abi_exit(void)
 {
        lttng_ust_abi_close_in_progress = 1;