Fix infinite loop in case an invalid pk3 file has been downloaded from the server. Thanks tjw for reporting (#3074)

git-svn-id: svn://svn.icculus.org/quake3/trunk@1686 edf5b092-35ff-0310-97b2-ce42778d08ea

2 files changed, 58 insertions, 15 deletions

diff --git a/code/qcommon/files.c b/code/qcommon/files.c
index 249470b..3584e30 100644
--- a/code/qcommon/files.c
+++ b/code/qcommon/files.c
@@ -1660,7 +1660,7 @@ Creates a new pak_t in the search chain for the contents
 of a zip file.
 =================
 */
-static pack_t *FS_LoadZipFile( char *zipfile, const char *basename )
+static pack_t *FS_LoadZipFile(const char *zipfile, const char *basename)
 {
 	fileInPack_t	*buildBuffer;
 	pack_t			*pack;
@@ -1683,8 +1683,6 @@ static pack_t *FS_LoadZipFile( char *zipfile, const char *basename )
 	if (err != UNZ_OK)
 		return NULL;
 
-	fs_packFiles += gi.number_entry;
-
 	len = 0;
 	unzGoToFirstFile(uf);
 	for (i = 0; i < gi.number_entry; i++)
@@ -1751,8 +1749,8 @@ static pack_t *FS_LoadZipFile( char *zipfile, const char *basename )
 		unzGoToNextFile(uf);
 	}
 
-	pack->checksum = Com_BlockChecksum( &fs_headerLongs[ 1 ], 4 * ( fs_numHeaderLongs - 1 ) );
-	pack->pure_checksum = Com_BlockChecksum( fs_headerLongs, 4 * fs_numHeaderLongs );
+	pack->checksum = Com_BlockChecksum( &fs_headerLongs[ 1 ], sizeof(*fs_headerLongs) * ( fs_numHeaderLongs - 1 ) );
+	pack->pure_checksum = Com_BlockChecksum( fs_headerLongs, sizeof(*fs_headerLongs) * fs_numHeaderLongs );
 	pack->checksum = LittleLong( pack->checksum );
 	pack->pure_checksum = LittleLong( pack->pure_checksum );
 
@@ -1763,6 +1761,50 @@ static pack_t *FS_LoadZipFile( char *zipfile, const char *basename )
 }
 
 /*
+=================
+FS_FreePak
+
+Frees a pak structure and releases all associated resources
+=================
+*/
+
+static void FS_FreePak(pack_t *thepak)
+{
+	unzClose(thepak->handle);
+	Z_Free(thepak->buildBuffer);
+	Z_Free(thepak);
+}
+
+/*
+=================
+FS_GetZipChecksum
+
+Compares whether the given pak file matches a referenced checksum
+=================
+*/
+qboolean FS_CompareZipChecksum(const char *zipfile)
+{
+	pack_t *thepak;
+	int index, checksum;
+	
+	thepak = FS_LoadZipFile(zipfile, "");
+	
+	if(!thepak)
+		return qfalse;
+	
+	checksum = thepak->checksum;
+	FS_FreePak(thepak);
+	
+	for(index = 0; index < fs_numServerReferencedPaks; index++)
+	{
+		if(checksum == fs_serverReferencedPaks[index])
+			return qtrue;
+	}
+	
+	return qfalse;
+}
+
+/*
 =================================================================================
 
 DIRECTORY SCANNING FUNCTIONS
@@ -2466,6 +2508,8 @@ void FS_AddGameDirectory( const char *path, const char *dir ) {
 			continue;
 		// store the game name for downloading
 		strcpy(pak->pakGamename, dir);
+		
+		fs_packFiles += pak->numfiles;
 
 		search = Z_Malloc (sizeof(searchpath_t));
 		search->pack = pak;
@@ -2655,18 +2699,16 @@ void FS_Shutdown( qboolean closemfp ) {
 	}
 
 	// free everything
-	for ( p = fs_searchpaths ; p ; p = next ) {
+	for(p = fs_searchpaths; p; p = next)
+	{
 		next = p->next;
 
-		if ( p->pack ) {
-			unzClose(p->pack->handle);
-			Z_Free( p->pack->buildBuffer );
-			Z_Free( p->pack );
-		}
-		if ( p->dir ) {
-			Z_Free( p->dir );
-		}
-		Z_Free( p );
+		if(p->pack)
+			FS_FreePak(p->pack);
+		if (p->dir)
+			Z_Free(p->dir);
+
+		Z_Free(p);
 	}
 
 	// any FS_ calls will now be an error until reinitialized
diff --git a/code/qcommon/qcommon.h b/code/qcommon/qcommon.h
index d1cc2fd..566687c 100644
--- a/code/qcommon/qcommon.h
+++ b/code/qcommon/qcommon.h
@@ -605,6 +605,7 @@ qboolean FS_FileExists( const char *file );
 
 qboolean FS_CreatePath (char *OSPath);
 char   *FS_BuildOSPath( const char *base, const char *game, const char *qpath );
+qboolean FS_CompareZipChecksum(const char *zipfile);
 
 int		FS_LoadStack( void );