modetest: add support for parsing big-endian formats

When specifying a frame buffer format like "RG16_BE" (big-endian RG16),
modetest still uses the little-endian variant, as the format string is
truncated to four characters.

Fix this by increasing the format string size to 8 bytes (7 characters +
NUL terminator).

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
v5:
  - Add Reviewed-by,

v4:
  - No changes,

v3:
  - Update for suffix change from "be" to "_BE", cfr. commit
    ffb9375a505700ad ("xf86drm: handle DRM_FORMAT_BIG_ENDIAN in
    drmGetFormatName()"),
  - Replace hardcoded numbers in code by sizeof(),

v2:
  - New.

1 files changed, 9 insertions, 6 deletions

diff --git a/tests/modetest/modetest.c b/tests/modetest/modetest.c
index 9b1aa537..cc96015f 100644
--- a/tests/modetest/modetest.c
+++ b/tests/modetest/modetest.c
@@ -817,7 +817,7 @@ struct pipe_arg {
 	unsigned int num_cons;
 	uint32_t crtc_id;
 	char mode_str[64];
-	char format_str[5];
+	char format_str[8]; /* need to leave room for "_BE" and terminating \0 */
 	float vrefresh;
 	unsigned int fourcc;
 	drmModeModeInfo *mode;
@@ -841,7 +841,7 @@ struct plane_arg {
 	unsigned int old_fb_id;
 	struct bo *bo;
 	struct bo *old_bo;
-	char format_str[5]; /* need to leave room for terminating \0 */
+	char format_str[8]; /* need to leave room for "_BE" and terminating \0 */
 	unsigned int fourcc;
 };
 
@@ -2032,8 +2032,9 @@ static int parse_connector(struct pipe_arg *pipe, const char *arg)
 	}
 
 	if (*p == '@') {
-		strncpy(pipe->format_str, p + 1, 4);
-		pipe->format_str[4] = '\0';
+		len = sizeof(pipe->format_str) - 1;
+		strncpy(pipe->format_str, p + 1, len);
+		pipe->format_str[len] = '\0';
 	}
 
 	pipe->fourcc = util_format_fourcc(pipe->format_str);
@@ -2047,6 +2048,7 @@ static int parse_connector(struct pipe_arg *pipe, const char *arg)
 
 static int parse_plane(struct plane_arg *plane, const char *p)
 {
+	unsigned int len;
 	char *end;
 
 	plane->plane_id = strtoul(p, &end, 10);
@@ -2085,8 +2087,9 @@ static int parse_plane(struct plane_arg *plane, const char *p)
 	}
 
 	if (*end == '@') {
-		strncpy(plane->format_str, end + 1, 4);
-		plane->format_str[4] = '\0';
+		len = sizeof(plane->format_str) - 1;
+		strncpy(plane->format_str, end + 1, len);
+		plane->format_str[len] = '\0';
 	} else {
 		strcpy(plane->format_str, "XR24");
 	}