From: Byrial Jensen <byrial@vip.cybercity.dk>
Date: Thu, 22 Dec 2011 13:30:08 +0000 (+0100)
Subject: Fix checking of return value from snprintf()
X-Git-Url: http://winboard.nl/cgi-bin?a=commitdiff_plain;h=a7ba1da07dbc23fe0e310d51b7bdf2d2a1bc1004;p=xboard.git

Fix checking of return value from snprintf()

snprintf() returns the needed space excluding the trailing 0 byte, so
it has truncated if the returned valued is greater than or EQUAL TO the buffersize
---

diff --git a/args.h b/args.h
index 6ea0237..6f51446 100644
--- a/args.h
+++ b/args.h
@@ -768,7 +768,7 @@ ExitArgError(char *msg, char *badArg, Boolean quit)
   int len;
 
   len = snprintf(buf,MSG_SIZ, "%s %s", msg, badArg);
-  if( (len > MSG_SIZ) && appData.debugMode )
+  if( (len >= MSG_SIZ) && appData.debugMode )
     fprintf(debugFP, "ExitArgError: buffer truncated. Input: msg=%s badArg=%s\n", msg, badArg);
 
   if(!quit) { printf(_("%s in settings file\n"), buf); return; } // DisplayError does not work yet at this stage...
@@ -820,7 +820,7 @@ ParseSettingsFile(char *name, char **addr)
   if(!ok && strchr(name, '.') == NULL)
     { // append default file-name extension '.ini' when needed
       len = snprintf(buf,MSG_SIZ, "%s.ini", name);
-      if( (len > MSG_SIZ) && appData.debugMode )
+      if( (len >= MSG_SIZ) && appData.debugMode )
 	fprintf(debugFP, "ParseSettingsFile: buffer truncated. Input: name=%s \n",name);
 
       ok = MySearchPath(installDir, buf, fullname);
@@ -1267,7 +1267,7 @@ InitAppData(char *lpCmdLine)
       if(p != NULL)
 	{ // engine command line contains WinBoard options
           len = snprintf(buf, MSG_SIZ, p+6, f, f, f, f, f, f, f, f, f, f); // replace %s in them by "first"
-	  if( (len > MSG_SIZ) && appData.debugMode )
+	  if( (len >= MSG_SIZ) && appData.debugMode )
 	    fprintf(debugFP, "InitAppData: buffer truncated.\n");
 
           ParseArgs(StringGet, &q);
@@ -1284,7 +1284,7 @@ InitAppData(char *lpCmdLine)
       if(p != NULL)
 	{ // engine command line contains WinBoard options
           len = snprintf(buf,MSG_SIZ, p+6, s, s, s, s, s, s, s, s, s, s); // replace %s in them by "first"
-	  if( (len > MSG_SIZ) && appData.debugMode )
+	  if( (len >= MSG_SIZ) && appData.debugMode )
 	    fprintf(debugFP, "InitAppData: buffer truncated.\n");
 
           ParseArgs(StringGet, &q);
@@ -1483,13 +1483,13 @@ GetArgValue(char *name)
       return TRUE;
     case ArgInt:
       len = snprintf(name, MSG_SIZ, "%d", *(int*) ad->argLoc);
-      if( (len > MSG_SIZ) && appData.debugMode )
+      if( (len >= MSG_SIZ) && appData.debugMode )
 	fprintf(debugFP, "GetArgValue: buffer truncated.\n");
 
       return TRUE;
     case ArgBoolean:
       len = snprintf(name, MSG_SIZ, "%s", *(Boolean*) ad->argLoc ? "true" : "false");
-      if( (len > MSG_SIZ) && appData.debugMode )
+      if( (len >= MSG_SIZ) && appData.debugMode )
 	fprintf(debugFP, "GetArgValue: buffer truncated.\n");
 
       return TRUE;
diff --git a/backend.c b/backend.c
index 935b9a0..8dc8f07 100644
--- a/backend.c
+++ b/backend.c
@@ -815,7 +815,7 @@ InitEngine(ChessProgramState *cps, int n)
 
 	len = snprintf(buf, MSG_SIZ, _("protocol version %d not supported"),
 		       appData.protocolVersion[n]);
-	if( (len > MSG_SIZ) && appData.debugMode )
+	if( (len >= MSG_SIZ) && appData.debugMode )
 	  fprintf(debugFP, "InitBackEnd1: buffer truncated.\n");
 
 	DisplayFatalError(buf, 0, 2);
@@ -1062,7 +1062,7 @@ InitBackEnd1()
       case VariantKriegspiel:   /* need to hide pieces and move details */
 	/* case VariantFischeRandom: (Fabien: moved below) */
 	len = snprintf(buf,MSG_SIZ, _("Variant %s supported only in ICS mode"), appData.variant);
-	if( (len > MSG_SIZ) && appData.debugMode )
+	if( (len >= MSG_SIZ) && appData.debugMode )
 	  fprintf(debugFP, "InitBackEnd1: buffer truncated.\n");
 
 	DisplayFatalError(buf, 0, 2);
@@ -1080,7 +1080,7 @@ InitBackEnd1()
       case Variant36:
       default:
 	len = snprintf(buf, MSG_SIZ, _("Unknown variant name %s"), appData.variant);
-	if( (len > MSG_SIZ) && appData.debugMode )
+	if( (len >= MSG_SIZ) && appData.debugMode )
 	  fprintf(debugFP, "InitBackEnd1: buffer truncated.\n");
 
 	DisplayFatalError(buf, 0, 2);
@@ -1485,7 +1485,7 @@ InitBackEnd3 P((void))
 	      len = snprintf(buf, MSG_SIZ, _("Could not connect to host %s, port %s"),
 			appData.icsHost, appData.icsPort);
 
-	    if( (len > MSG_SIZ) && appData.debugMode )
+	    if( (len >= MSG_SIZ) && appData.debugMode )
 	      fprintf(debugFP, "InitBackEnd3: buffer truncated.\n");
 
 	    DisplayFatalError(buf, err, 1);
@@ -1539,7 +1539,7 @@ InitBackEnd3 P((void))
       initialMode = Training;
     } else {
       len = snprintf(buf, MSG_SIZ, _("Unknown initialMode %s"), appData.initialMode);
-      if( (len > MSG_SIZ) && appData.debugMode )
+      if( (len >= MSG_SIZ) && appData.debugMode )
 	fprintf(debugFP, "InitBackEnd3: buffer truncated.\n");
 
       DisplayFatalError(buf, 0, 2);
@@ -2138,7 +2138,7 @@ StringToVariant(e)
 	  break;
 	default:
 	  len = snprintf(buf, MSG_SIZ, _("Unknown wild type %d"), wnum);
-	  if( (len > MSG_SIZ) && appData.debugMode )
+	  if( (len >= MSG_SIZ) && appData.debugMode )
 	    fprintf(debugFP, "StringToVariant: buffer truncated.\n");
 
 	  DisplayError(buf, 0);