fall back to system() in handleSystemCommand: when terminating to avo…

…id segfaults

git-svn-id: https://svn.r-project.org/R-packages/trunk/Mac-GUI@7903 694ef91d-65df-0310-b7bb-92e67a308ead

RController.m

@@ -1627,14 +1627,25 @@ - (int) handleInstalledPackages: (int) count withNames: (char**) name installedV
 	return 0;
 }
 
-- (int) handleSystemCommand: (char*) cmd
+- (int) handleSystemCommand: (const char*) cmd
 {	
 	int cstat=-1;
 	pid_t pid;
 
+    // we had issues with fork() and libxpc during cleanup, so fall back to regular system()
+    // during termination
+    if (terminating) {
+        signal(SIGINT, SIG_DFL);
+        signal(SIGTERM, SIG_DFL);
+        signal(SIGQUIT, SIG_DFL);
+        signal(SIGALRM, SIG_DFL);
+        signal(SIGCHLD, SIG_DFL);
+        return system(cmd);
+    }
+
 	if ([self getRootFlag]) {
 		FILE *f;
-		char *argv[3] = { "-c", cmd, 0 };
+		const char *argv[3] = { "-c", cmd, 0 };
 		int res;
  		NSBundle *b = [NSBundle mainBundle];
 		char *sushPath = 0;

REngine/Rcallbacks.h

@@ -68,7 +68,7 @@
 // return value is unused so far
 - (int) handleInstalledPackages: (int) count withNames: (char**) name installedVersions: (char**) iver repositoryVersions: (char**) rver update: (BOOL*) stat label: (char*) label;
 // its usage is identical to that of the 'system' command
-- (int) handleSystemCommand: (char*) cmd;
+- (int) handleSystemCommand: (const char*) cmd;
 - (int) handleHelpSearch: (int) count withTopics: (char**) topics packages: (char**) pkgs descriptions: (char**) descs urls: (char**) urls title: (char*) title;
 - (int) handleCustomPrint: (char*) type withObject: (RSEXP*) obj;
 @end