X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;ds=sidebyside;f=xtrlock.c;h=6117c6fadbc596805a9f6f32fded1fb5ae0c07b2;hb=6f8396e3a1607537a1cd6903d3d0f1a14e6f3476;hp=3d5ce704eb5e4bf91059c15364555f1b54de11d3;hpb=8382c6f9d7f17373aa235ebe1a242bf56e7eb25e;p=xtrlock.git

diff --git a/xtrlock.c b/xtrlock.c
index 3d5ce70..6117c6f 100644
--- a/xtrlock.c
+++ b/xtrlock.c
@@ -81,19 +81,27 @@ int main(int argc, char **argv){
   Cursor cursor;
   Pixmap csr_source,csr_mask;
   XColor csr_fg, csr_bg, dummy, black;
-  int ret, screen, blank = 0;
+  int ret, screen, blank = 0, fork_after = 0;
 #ifdef SHADOW_PWD
   struct spwd *sp;
 #endif
   struct timeval tv;
   int tvt, gs;
 
-  if ((argc == 2) && (strcmp(argv[1], "-b") == 0)) {
-    blank = 1;
-  } else if (argc > 1) {
-    fprintf(stderr,"xtrlock (version %s); usage: xtrlock [-b]\n",
-            program_version);
-    exit(1);
+  while (argc > 1) {
+    if ((strcmp(argv[1], "-b") == 0)) {
+      blank = 1;
+      argc--;
+      argv++;
+    } else if ((strcmp(argv[1], "-f") == 0)) {
+      fork_after = 1;
+      argc--;
+      argv++;
+    } else {
+      fprintf(stderr,"xtrlock (version %s); usage: xtrlock [-b] [-f]\n",
+              program_version);
+      exit(1);
+    }
   }
   
   errno=0;  pw= getpwuid(getuid());
@@ -108,10 +116,10 @@ int main(int argc, char **argv){
   /* logically, if we need to do the following then the same 
      applies to being installed setgid shadow.  
      we do this first, because of a bug in linux. --jdamery */ 
-  setgid(getgid());
+  if (setgid(getgid())) { perror("setgid"); exit(1); }
   /* we can be installed setuid root to support shadow passwords,
      and we don't need root privileges any longer.  --marekm */
-  setuid(getuid());
+  if (setuid(getuid())) { perror("setuid"); exit(1); }
 
   if (strlen(pw->pw_passwd) < 13) {
     fputs("password entry has no pwd\n",stderr); exit(1);
@@ -208,6 +216,17 @@ int main(int argc, char **argv){
     exit(1);
   }
 
+  if (fork_after) {
+    pid_t pid = fork();
+    if (pid < 0) {
+      fprintf(stderr,"xtrlock (version %s): cannot fork: %s\n",
+              program_version, strerror(errno));
+      exit(1);
+    } else if (pid > 0) {
+      exit(0);
+    }
+  }
+
   for (;;) {
     XNextEvent(display,&ev);
     switch (ev.type) {