platsch: fix sign compare for int/unsigned

The sizeof operator will return a long unsigned int which raises a sign
compare issue when compared to int. Also fix similar issues where we
compare an int with an unsigned int by casting the unsigned int to int
using INT_MAX as the limit.

Signed-off-by: Rouven Czerwinski <[email protected]>

platsch.c

@@ -33,6 +33,7 @@
 #include <sys/stat.h>
 #include <sys/mman.h>
 #include <fcntl.h>
+#include <limits.h>
 
 #include <xf86drm.h>
 #include <xf86drmMode.h>
@@ -124,7 +125,7 @@ void draw_buffer(struct modeset_dev *dev, const char *dir, const char *base)
 	ret = snprintf(filename, sizeof(filename),
 		       "%s/%s-%ux%u-%s.bin",
 		       dir, base, dev->width, dev->height, dev->format->name);
-	if (ret >= sizeof(filename)) {
+	if (ret >= ((int)sizeof(filename) & INT_MAX)) {
 		error("Failed to fit filename into buffer\n");
 		return;
 	}
@@ -183,7 +184,7 @@ static int drmprepare_crtc(int fd, drmModeRes *res, drmModeConnector *conn,
 			assert(crtc_id >= 0);
 
 			for (iter = modeset_list; iter; iter = iter->next) {
-				if (iter->crtc_id == crtc_id) {
+				if (((int)iter->crtc_id & INT_MAX) == crtc_id) {
 					crtc_id = -1;
 					break;
 				}
@@ -229,7 +230,7 @@ static int drmprepare_crtc(int fd, drmModeRes *res, drmModeConnector *conn,
 			/* check that no other device already uses this CRTC */
 			crtc_id = res->crtcs[j];
 			for (iter = modeset_list; iter; iter = iter->next) {
-				if (iter->crtc_id == crtc_id) {
+				if (((int)iter->crtc_id & INT_MAX) == crtc_id) {
 					crtc_id = -1;
 					break;
 				}
@@ -375,7 +376,7 @@ static int set_env_connector_mode(drmModeConnector *conn,
 	ret = snprintf(mode_env_name, sizeof(mode_env_name), "platsch_%s%u_mode",
 		       connector_type_name, conn->connector_type_id);
 	free(connector_type_name);
-	if (ret >= sizeof(mode_env_name)) {
+	if (ret >= ((int)sizeof(mode_env_name) & INT_MAX)) {
 		error("failed to fit platsch env mode variable name into buffer\n");
 		return -EFAULT;
 	}
@@ -612,7 +613,7 @@ int main(int argc, char *argv[])
 		 * XXX: Loop through drm devices to find one with connectors.
 		 */
 		ret = snprintf(drmdev, sizeof(drmdev), DRM_DEV_NAME, DRM_DIR_NAME, i);
-		if (ret >= sizeof(drmdev)) {
+		if (ret >= (int)sizeof(drmdev)) {
 			error("Huh, device name overflowed buffer\n");
 			goto execinit;
 		}