Fix: header size larger than 256 bytes

When adding large context (e.g. callstack), headers larger than 256
bytes cause discrepancy between calculated size and size written into
the trace buffers. This generates a corrupted trace and triggers a
warning in ring buffer backend, which triggers a safety net disabling
tracing for the current channel.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

diff --git a/liblttng-ust/lttng-ring-buffer-client.h b/liblttng-ust/lttng-ring-buffer-client.h
index 7dfb144d1f99e3ef8055384366535a3afcdcee02..e6bdd1d148779c93ec9ab63c500ec279e5af4d86 100644 (file)
--- a/liblttng-ust/lttng-ring-buffer-client.h
+++ b/liblttng-ust/lttng-ring-buffer-client.h
@@ -110,7 +110,7 @@ void ctx_record(struct lttng_ust_lib_ring_buffer_ctx *bufctx,
  * contains.
  */
 static __inline__
-unsigned char record_header_size(const struct lttng_ust_lib_ring_buffer_config *config,
+size_t record_header_size(const struct lttng_ust_lib_ring_buffer_config *config,
                                 struct channel *chan, size_t offset,
                                 size_t *pre_header_padding,
                                 struct lttng_ust_lib_ring_buffer_ctx *ctx)

diff --git a/liblttng-ust/lttng-ring-buffer-metadata-client.h b/liblttng-ust/lttng-ring-buffer-metadata-client.h
index 3352e1f29649cd4154d6e81ed2fd61da60f64d16..e71a0e90ded17146d7631b5d3645381dde63a3a8 100644 (file)
--- a/liblttng-ust/lttng-ring-buffer-metadata-client.h
+++ b/liblttng-ust/lttng-ring-buffer-metadata-client.h
@@ -52,7 +52,7 @@ static inline uint64_t lib_ring_buffer_clock_read(struct channel *chan)
 }
 
 static inline
-unsigned char record_header_size(const struct lttng_ust_lib_ring_buffer_config *config,
+size_t record_header_size(const struct lttng_ust_lib_ring_buffer_config *config,
                                 struct channel *chan, size_t offset,
                                 size_t *pre_header_padding,
                                 struct lttng_ust_lib_ring_buffer_ctx *ctx)