From ddcfa59c967c6fef53448f527dbe438328e9c4b7 Mon Sep 17 00:00:00 2001
From: Eric Petit <eric@lapsus.org>
Date: Mon, 29 Jan 2007 08:24:09 +0000
Subject: [PATCH] Always take the global lock when accessing the torrent list
 (fixes a race condition crash)

---
 libtransmission/ratecontrol.c  | 4 ++++
 libtransmission/torrent.c      | 5 ++++-
 libtransmission/transmission.c | 2 ++
 3 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/libtransmission/ratecontrol.c b/libtransmission/ratecontrol.c
index 7e8eb4a86..9e45f5022 100644
--- a/libtransmission/ratecontrol.c
+++ b/libtransmission/ratecontrol.c
@@ -23,6 +23,7 @@
  *****************************************************************************/
 
 #include "transmission.h"
+#include "shared.h"
 
 /* Maximum number of packets we keep track of. Since most packets are
  * 1 KB, it means we remember the last 2 MB transferred */
@@ -93,6 +94,7 @@ int tr_rcCanGlobalTransfer( tr_handle_t * h, int isUpload )
         return limit < 0;
     }
     
+    tr_sharedLock( h->shared );
     for( tor = h->torrentList; tor; tor = tor->next )
     {
         if( tor->customSpeedLimit )
@@ -107,9 +109,11 @@ int tr_rcCanGlobalTransfer( tr_handle_t * h, int isUpload )
         
         if( rate >= (float)limit )
         {
+            tr_sharedUnlock( h->shared );
             return 0;
         }
     }
+    tr_sharedUnlock( h->shared );
     
     return 1;
 }
diff --git a/libtransmission/torrent.c b/libtransmission/torrent.c
index 336e293a9..5e006fa92 100644
--- a/libtransmission/torrent.c
+++ b/libtransmission/torrent.c
@@ -97,6 +97,8 @@ static tr_torrent_t * torrentRealInit( tr_handle_t * h, tr_torrent_t * tor,
     inf        = &tor->info;
     inf->flags = flags;
 
+    tr_sharedLock( h->shared );
+
     /* Make sure this torrent is not already open */
     for( tor_tmp = h->torrentList; tor_tmp; tor_tmp = tor_tmp->next )
     {
@@ -106,6 +108,7 @@ static tr_torrent_t * torrentRealInit( tr_handle_t * h, tr_torrent_t * tor,
             *error = TR_EDUPLICATE;
             tr_metainfoFree( &tor->info );
             free( tor );
+            tr_sharedUnlock( h->shared );
             return NULL;
         }
     }
@@ -136,7 +139,6 @@ static tr_torrent_t * torrentRealInit( tr_handle_t * h, tr_torrent_t * tor,
     tor->swarmspeed     = tr_rcInit();
  
     /* We have a new torrent */
-    tr_sharedLock( h->shared );
     tor->publicPort = tr_sharedGetPublicPort( h->shared );
     tor->prev       = NULL;
     tor->next       = h->torrentList;
@@ -146,6 +148,7 @@ static tr_torrent_t * torrentRealInit( tr_handle_t * h, tr_torrent_t * tor,
     }
     h->torrentList = tor;
     (h->torrentCount)++;
+
     tr_sharedUnlock( h->shared );
 
     if( !h->isPortSet )
diff --git a/libtransmission/transmission.c b/libtransmission/transmission.c
index 69f3a24a6..6ef08c1f0 100644
--- a/libtransmission/transmission.c
+++ b/libtransmission/transmission.c
@@ -108,6 +108,7 @@ void tr_torrentRates( tr_handle_t * h, float * dl, float * ul )
 
     *dl = 0.0;
     *ul = 0.0;
+    tr_sharedLock( h->shared );
     for( tor = h->torrentList; tor; tor = tor->next )
     {
         tr_lockLock( &tor->lock );
@@ -116,6 +117,7 @@ void tr_torrentRates( tr_handle_t * h, float * dl, float * ul )
         *ul += tr_rcRate( tor->upload );
         tr_lockUnlock( &tor->lock );
     }
+    tr_sharedUnlock( h->shared );
 }
 
 int tr_torrentCount( tr_handle_t * h )