[rtmpdump] [PATCH] Allocate the channel arrays dynamically

[Martin Storsjo]

This avoids having to allocate space for all theoretical channels
if most of them aren't used. This drops the size of the full
RTMP struct from over 1200 KB to 16 KB (on 64 bit), and as long as
only channels with a low number are used, the amount of total
allocated memory stays far below what it was before.
---
 librtmp/rtmp.c |   60 +++++++++++++++++++++++++++++++++++++++++++++++++++-----
 librtmp/rtmp.h |    8 +++++---
 2 files changed, 60 insertions(+), 8 deletions(-)

diff --git a/librtmp/rtmp.c b/librtmp/rtmp.c
index 37a05ad..74d5552 100644
--- a/librtmp/rtmp.c
+++ b/librtmp/rtmp.c
@@ -1101,7 +1101,8 @@ RTMP_GetNextMediaPacket(RTMP *r, RTMPPacket *packet)
   if (bHasMediaPacket)
     r->m_bPlaying = TRUE;
   else if (r->m_sb.sb_timedout && !r->m_pausing)
-    r->m_pauseStamp = r->m_channelTimestamp[r->m_mediaChannel];
+    r->m_pauseStamp = r->m_mediaChannel < r->m_channelsAllocatedIn ?
+                      r->m_channelTimestamp[r->m_mediaChannel] : 0;
 
   return bHasMediaPacket;
 }
@@ -1873,7 +1874,8 @@ RTMP_SendPause(RTMP *r, int DoPause, int iTime)
 int RTMP_Pause(RTMP *r, int DoPause)
 {
   if (DoPause)
-    r->m_pauseStamp = r->m_channelTimestamp[r->m_mediaChannel];
+    r->m_pauseStamp = r->m_mediaChannel < r->m_channelsAllocatedIn ?
+                      r->m_channelTimestamp[r->m_mediaChannel] : 0;
   return RTMP_SendPause(r, DoPause, r->m_pauseStamp);
 }
 
@@ -2828,7 +2830,8 @@ HandleCtrl(RTMP *r, const RTMPPacket *packet)
 	    break;
 	  if (!r->m_pausing)
 	    {
-	      r->m_pauseStamp = r->m_channelTimestamp[r->m_mediaChannel];
+	      r->m_pauseStamp = r->m_mediaChannel < r->m_channelsAllocatedIn ?
+	                        r->m_channelTimestamp[r->m_mediaChannel] : 0;
 	      RTMP_SendPause(r, TRUE, r->m_pauseStamp);
 	      r->m_pausing = 1;
 	    }
@@ -2973,6 +2976,26 @@ RTMP_ReadPacket(RTMP *r, RTMPPacket *packet)
 
   nSize = packetSize[packet->m_headerType];
 
+  if (packet->m_nChannel >= r->m_channelsAllocatedIn)
+    {
+      int n = packet->m_nChannel + 10;
+      int *timestamp = realloc(r->m_channelTimestamp, sizeof(int) * n);
+      RTMPPacket **packets = realloc(r->m_vecChannelsIn, sizeof(RTMPPacket*) * n);
+      if (!timestamp)
+        free(r->m_channelTimestamp);
+      if (!packets)
+        free(r->m_vecChannelsIn);
+      r->m_channelTimestamp = timestamp;
+      r->m_vecChannelsIn = packets;
+      if (!timestamp || !packets) {
+        r->m_channelsAllocatedIn = 0;
+        return FALSE;
+      }
+      memset(r->m_channelTimestamp + r->m_channelsAllocatedIn, 0, sizeof(int) * (n - r->m_channelsAllocatedIn));
+      memset(r->m_vecChannelsIn + r->m_channelsAllocatedIn, 0, sizeof(RTMPPacket*) * (n - r->m_channelsAllocatedIn));
+      r->m_channelsAllocatedIn = n;
+    }
+
   if (nSize == RTMP_LARGE_HEADER_SIZE)	/* if we get a full header the timestamp is absolute */
     packet->m_hasAbsTimestamp = TRUE;
 
@@ -3248,7 +3271,7 @@ RTMP_SendChunk(RTMP *r, RTMPChunk *chunk)
 int
 RTMP_SendPacket(RTMP *r, RTMPPacket *packet, int queue)
 {
-  const RTMPPacket *prevPacket = r->m_vecChannelsOut[packet->m_nChannel];
+  const RTMPPacket *prevPacket;
   uint32_t last = 0;
   int nSize;
   int hSize, cSize;
@@ -3258,6 +3281,22 @@ RTMP_SendPacket(RTMP *r, RTMPPacket *packet, int queue)
   int nChunkSize;
   int tlen;
 
+  if (packet->m_nChannel >= r->m_channelsAllocatedOut)
+    {
+      int n = packet->m_nChannel + 10;
+      RTMPPacket **packets = realloc(r->m_vecChannelsOut, sizeof(RTMPPacket*) * n);
+      if (!packets) {
+        free(r->m_vecChannelsOut);
+        r->m_vecChannelsOut = NULL;
+        r->m_channelsAllocatedOut = 0;
+        return FALSE;
+      }
+      r->m_vecChannelsOut = packets;
+      memset(r->m_vecChannelsOut + r->m_channelsAllocatedOut, 0, sizeof(RTMPPacket*) * (n - r->m_channelsAllocatedOut));
+      r->m_channelsAllocatedOut = n;
+    }
+
+  prevPacket = r->m_vecChannelsOut[packet->m_nChannel];
   if (prevPacket && packet->m_headerType != RTMP_PACKET_SIZE_LARGE)
     {
       /* compress a bit by using the prev packet's attributes */
@@ -3494,7 +3533,7 @@ RTMP_Close(RTMP *r)
   r->m_write.m_nBytesRead = 0;
   RTMPPacket_Free(&r->m_write);
 
-  for (i = 0; i < RTMP_CHANNELS; i++)
+  for (i = 0; i < r->m_channelsAllocatedIn; i++)
     {
       if (r->m_vecChannelsIn[i])
 	{
@@ -3502,12 +3541,23 @@ RTMP_Close(RTMP *r)
 	  free(r->m_vecChannelsIn[i]);
 	  r->m_vecChannelsIn[i] = NULL;
 	}
+    }
+  free(r->m_vecChannelsIn);
+  r->m_vecChannelsIn = NULL;
+  free(r->m_channelTimestamp);
+  r->m_channelTimestamp = NULL;
+  r->m_channelsAllocatedIn = 0;
+  for (i = 0; i < r->m_channelsAllocatedOut; i++)
+    {
       if (r->m_vecChannelsOut[i])
 	{
 	  free(r->m_vecChannelsOut[i]);
 	  r->m_vecChannelsOut[i] = NULL;
 	}
     }
+  free(r->m_vecChannelsOut);
+  r->m_vecChannelsOut = NULL;
+  r->m_channelsAllocatedOut = 0;
   AV_clear(r->m_methodCalls, r->m_numCalls);
   r->m_methodCalls = NULL;
   r->m_numCalls = 0;
diff --git a/librtmp/rtmp.h b/librtmp/rtmp.h
index 6b2ae5b..558e0ac 100644
--- a/librtmp/rtmp.h
+++ b/librtmp/rtmp.h
@@ -253,9 +253,11 @@ extern "C"
     int m_numCalls;
     RTMP_METHOD *m_methodCalls;	/* remote method calls queue */
 
-    RTMPPacket *m_vecChannelsIn[RTMP_CHANNELS];
-    RTMPPacket *m_vecChannelsOut[RTMP_CHANNELS];
-    int m_channelTimestamp[RTMP_CHANNELS];	/* abs timestamp of last packet */
+    int m_channelsAllocatedIn;
+    int m_channelsAllocatedOut;
+    RTMPPacket **m_vecChannelsIn;
+    RTMPPacket **m_vecChannelsOut;
+    int *m_channelTimestamp;	/* abs timestamp of last packet */
 
     double m_fAudioCodecs;	/* audioCodecs for the connect packet */
     double m_fVideoCodecs;	/* videoCodecs for the connect packet */
-- 
1.7.9.4