X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=patch-delta.c;h=c0e13114351c4ea427ddfe4d9e9c20a541201ad6;hb=5b5d4d9e1b31997b3179e6a253d47b7eea03d0fa;hp=b68dd13c63be4a3834354916398b1ab4827334cc;hpb=69a2d426f0d249bca2c6f754b3c1283c0fa72fd4;p=git.git

diff --git a/patch-delta.c b/patch-delta.c
index b68dd13c..c0e13114 100644
--- a/patch-delta.c
+++ b/patch-delta.c
@@ -20,55 +20,39 @@ void *patch_delta(void *src_buf, unsigned long src_size,
 	const unsigned char *data, *top;
 	unsigned char *dst_buf, *out, cmd;
 	unsigned long size;
-	int i;
 
-	/* the smallest delta size possible is 4 bytes */
-	if (delta_size < 4)
+	if (delta_size < DELTA_SIZE_MIN)
 		return NULL;
 
 	data = delta_buf;
 	top = delta_buf + delta_size;
 
 	/* make sure the orig file size matches what we expect */
-	cmd = *data++;
-	size = cmd & ~0x80;
-	i = 7;
-	while (cmd & 0x80) {
-		cmd = *data++;
-		size |= (cmd & ~0x80) << i;
-		i += 7;
-	}
+	size = get_delta_hdr_size(&data);
 	if (size != src_size)
 		return NULL;
 
 	/* now the result size */
-	cmd = *data++;
-	size = cmd & ~0x80;
-	i = 7;
-	while (cmd & 0x80) {
-		cmd = *data++;
-		size |= (cmd & ~0x80) << i;
-		i += 7;
-	}
-	dst_buf = malloc(size);
+	size = get_delta_hdr_size(&data);
+	dst_buf = malloc(size + 1);
 	if (!dst_buf)
 		return NULL;
+	dst_buf[size] = 0;
 
 	out = dst_buf;
 	while (data < top) {
 		cmd = *data++;
 		if (cmd & 0x80) {
 			unsigned long cp_off = 0, cp_size = 0;
-			const unsigned char *buf;
 			if (cmd & 0x01) cp_off = *data++;
 			if (cmd & 0x02) cp_off |= (*data++ << 8);
 			if (cmd & 0x04) cp_off |= (*data++ << 16);
 			if (cmd & 0x08) cp_off |= (*data++ << 24);
 			if (cmd & 0x10) cp_size = *data++;
 			if (cmd & 0x20) cp_size |= (*data++ << 8);
+			if (cmd & 0x40) cp_size |= (*data++ << 16);
 			if (cp_size == 0) cp_size = 0x10000;
-			buf = (cmd & 0x40) ? dst_buf : src_buf;
-			memcpy(out, buf + cp_off, cp_size);
+			memcpy(out, src_buf + cp_off, cp_size);
 			out += cp_size;
 		} else {
 			memcpy(out, data, cmd);