X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=afh.c;h=4c5ddae51499984c02da75ae2898517c5d6e24fe;hp=86f34ace67e0efcba11fb9ddfe1a2f23ca2416b7;hb=1889013e900f08d5ee842a50dc13c66689ebf15b;hpb=97727c2e95cce064e03f495e97119cae447397d7

diff --git a/afh.c b/afh.c
index 86f34ace..4c5ddae5 100644
--- a/afh.c
+++ b/afh.c
@@ -60,22 +60,30 @@ static int cat_file(void *audio_file_data, struct afh_info *afhi)
 	int ret;
 	struct timeval stream_start;
 	long unsigned i, first_chunk, last_chunk;
-	char *buf;
+	const char *buf;
 	size_t size;
 
 
-	if (conf.begin_chunk_arg < 0)
-		return -ERRNO_TO_PARA_ERROR(EINVAL);
-	first_chunk = conf.begin_chunk_arg;
-
-	if (conf.end_chunk_given) {
-		if (conf.end_chunk_arg < 0)
-			return -ERRNO_TO_PARA_ERROR(EINVAL);
-		if (conf.end_chunk_arg >= afhi->chunks_total)
+	if (conf.begin_chunk_arg < 0) {
+		if (-conf.begin_chunk_arg > afhi->chunks_total)
 			return -ERRNO_TO_PARA_ERROR(EINVAL);
-		last_chunk = conf.end_chunk_arg;
+		first_chunk = afhi->chunks_total + conf.begin_chunk_arg;
+	} else
+		first_chunk = conf.begin_chunk_arg;
+	if (conf.end_chunk_given) {
+		if (conf.end_chunk_arg < 0) {
+			if (-conf.end_chunk_arg > afhi->chunks_total)
+				return -ERRNO_TO_PARA_ERROR(EINVAL);
+			last_chunk = afhi->chunks_total + conf.end_chunk_arg;
+		} else {
+			if (conf.end_chunk_arg >= afhi->chunks_total)
+				return -ERRNO_TO_PARA_ERROR(EINVAL);
+			last_chunk = conf.end_chunk_arg;
+		}
 	} else
 		last_chunk = afhi->chunks_total - 1;
+	if (first_chunk >= last_chunk)
+		return -ERRNO_TO_PARA_ERROR(EINVAL);
 	if (!afhi->chunks_total)
 		return 1;
 	afh_get_header(afhi, audio_file_data, &buf, &size);