From: Andre Noll <maan@systemlinux.org>
Date: Sun, 24 Oct 2010 17:27:55 +0000 (+0200)
Subject: vss: Introduce extra_header_buf.
X-Git-Tag: v0.4.6~19^2~5
X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=commitdiff_plain;h=ead9cdc8160656e868f1d709ad1a764f9dcc3a2f

vss: Introduce extra_header_buf.

For the same reasons the extra data buffer is necessary, we also need to reserve
an extra buffer for the header in order to not read-overflow the header buffer
provided by the new get_header() function.
---

diff --git a/vss.c b/vss.c
index 8b374521..2dab278d 100644
--- a/vss.c
+++ b/vss.c
@@ -167,6 +167,8 @@ struct fec_client {
 	struct timeval next_header_time;
 	/** Used for the last source pointer of an audio file. */
 	unsigned char *extra_src_buf;
+	/** Needed for the last slice of the audio file header. */
+	unsigned char *extra_header_buf;
 	/** Extra slices needed to store largest chunk + header. */
 	int num_extra_slices;
 	/** Contains the FEC-encoded data. */
@@ -327,6 +329,7 @@ static int initialize_fec_client(struct fec_client *fc, struct vss_task *vsst)
 	fc->src_data = para_realloc(fc->src_data, k * sizeof(char *));
 	fc->enc_buf = para_realloc(fc->enc_buf, fc->mps);
 	fc->extra_src_buf = para_realloc(fc->extra_src_buf, fc->mps);
+	fc->extra_header_buf = para_realloc(fc->extra_header_buf, fc->mps);
 
 	fc->state = FEC_STATE_READY_TO_RUN;
 	fc->next_header_time.tv_sec = 0;
@@ -516,12 +519,27 @@ static int setup_next_fec_group(struct fec_client *fc, struct vss_task *vsst)
 	fc->current_slice_num = 0;
 	if (g->num == 0)
 		set_group_timing(fc, vsst);
-
 	/* setup header slices */
 	buf = vsst->header_buf;
 	for (i = 0; i < g->num_header_slices; i++) {
-		fc->src_data[i] = (const unsigned char *)buf;
-		buf += g->slice_bytes;
+		if (buf + g->slice_bytes <= vsst->header_buf + vsst->header_len) {
+			fc->src_data[i] = (const unsigned char *)buf;
+			buf += g->slice_bytes;
+			continue;
+		}
+		/*
+		 * Can not use vss->header_buf for this slice as it
+		 * goes beyond the buffer. This slice will not be fully
+		 * used.
+		 */
+		uint32_t payload_size = vsst->header_buf
+			+ vsst->header_len - buf;
+		memcpy(fc->extra_header_buf, buf, payload_size);
+		if (payload_size < g->slice_bytes)
+			memset(fc->extra_header_buf + payload_size, 0,
+				g->slice_bytes - payload_size);
+		fc->src_data[i] = fc->extra_header_buf;
+		assert(i == g->num_header_slices - 1);
 	}
 
 	/* setup data slices */
@@ -530,8 +548,7 @@ static int setup_next_fec_group(struct fec_client *fc, struct vss_task *vsst)
 		if (buf + g->slice_bytes > vsst->map + mmd->size) {
 			/*
 			 * Can not use the memory mapped audio file for this
-			 * slice as it goes beyond the map. This slice will not
-			 * be fully used.
+			 * slice as it goes beyond the map.
 			 */
 			uint32_t payload_size = vsst->map + mmd->size - buf;
 			memcpy(fc->extra_src_buf, buf, payload_size);
@@ -627,6 +644,7 @@ void vss_del_fec_client(struct fec_client *fc)
 	free(fc->src_data);
 	free(fc->enc_buf);
 	free(fc->extra_src_buf);
+	free(fc->extra_header_buf);
 	fec_free(fc->parms);
 	free(fc);
 }