mesa: Include null terminator in GL_DEBUG_NEXT_LOGGED_MESSAGE_LENGTH.

From the KHR_debug spec:
"Applications can query the number of messages currently in the log by
 obtaining the value of DEBUG_LOGGED_MESSAGES, and the string length
 (including its null terminator) of the oldest message in the log
 through the value of DEBUG_NEXT_LOGGED_MESSAGE_LENGTH."

Because we weren't including the null terminator, many dEQP tests
called glGetDebugMessageLog with a bufSize parameter that was 1 too
small, and unable to contain the message, so we skipped returning it,
failing many cases.

Fixes 298 dEQP-GLES31.functional.debug.* tests.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Stephane Marchesin <stephane.marchesin@gmail.com>
Reviewed-by: Eduardo Lima Mitev <elima@igalia.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/src/mesa/main/debug_output.c b/src/mesa/main/debug_output.c
index c2b9f05..74be855 100644
--- a/src/mesa/main/debug_output.c
+++ b/src/mesa/main/debug_output.c
@@ -779,7 +779,7 @@ _mesa_get_debug_state_int(struct gl_context *ctx, GLenum pname)
       break;
    case GL_DEBUG_NEXT_LOGGED_MESSAGE_LENGTH:
       val = (debug->Log.NumMessages) ?
-         debug->Log.Messages[debug->Log.NextMessage].length : 0;
+         debug->Log.Messages[debug->Log.NextMessage].length + 1 : 0;
       break;
    case GL_DEBUG_GROUP_STACK_DEPTH:
       val = debug->CurrentGroup + 1;