X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=src%2Fcommon%2Fust-context-provider.h;h=43e75b4bcdaa448812dfb2c3e6790aaaba12aea1;hb=577f6dfc5dc2cbd4d6d82b453dabca36c4b78d1d;hp=d8c9a138c7d8f05e48a8b7dedc3fde565f2e4fa4;hpb=d6f956db3c0e55643fa547b6bebb82089a6615a7;p=lttng-ust.git

diff --git a/src/common/ust-context-provider.h b/src/common/ust-context-provider.h
index d8c9a138..43e75b4b 100644
--- a/src/common/ust-context-provider.h
+++ b/src/common/ust-context-provider.h
@@ -67,6 +67,27 @@ struct lttng_ust_context_provider {
 	/* End of base ABI. Fields below should be used after checking struct_size. */
 };
 
+/*
+ * Application context callback private data
+ *
+ * IMPORTANT: this structure is part of the ABI between the probe and
+ * UST. Fields need to be only added at the end, never reordered, never
+ * removed.
+ *
+ * The field @struct_size should be used to determine the size of the
+ * structure. It should be queried before using additional fields added
+ * at the end of the structure.
+ */
+
+struct lttng_ust_app_context {
+	uint32_t struct_size;
+
+	struct lttng_ust_event_field *event_field;
+	char *ctx_name;
+
+	/* End of base ABI. Fields below should be used after checking struct_size. */
+};
+
 /*
  * Returns an opaque pointer on success, which must be passed to
  * lttng_ust_context_provider_unregister for unregistration. Returns