util.c

   1 /*
   2  * (C)opyright MMVI Anselm R. Garbe <garbeam at gmail dot com>
   3  * See LICENSE file for license details.
   4  */
   5
   6 #include <stdarg.h>
   7 #include <stdio.h>
   8 #include <stdlib.h>
   9 #include <sys/types.h>
  10 #include <sys/wait.h>
  11 #include <unistd.h>
  12
  13 #include "dwm.h"
  14
  15 void
  16 error(const char *errstr, ...) {
  17         va_list ap;
  18         va_start(ap, errstr);
  19         vfprintf(stderr, errstr, ap);
  20         va_end(ap);
  21         exit(1);
  22 }
  23
  24 static void
  25 bad_malloc(unsigned int size)
  26 {
  27         fprintf(stderr, "fatal: could not malloc() %d bytes\n",
  28                         (int) size);
  29         exit(1);
  30 }
  31
  32 void *
  33 emallocz(unsigned int size)
  34 {
  35         void *res = calloc(1, size);
  36         if(!res)
  37                 bad_malloc(size);
  38         return res;
  39 }
  40
  41 void
  42 swap(void **p1, void **p2)
  43 {
  44         void *tmp = *p1;
  45         *p1 = *p2;
  46         *p2 = tmp;
  47 }
  48
  49 void
  50 spawn(Arg *arg)
  51 {
  52         char **argv = (char **)arg->argv;
  53         if(!argv || !argv[0])
  54                 return;
  55         if(fork() == 0) {
  56                 if(fork() == 0) {
  57                         if(dpy)
  58                                 close(ConnectionNumber(dpy));
  59                         setsid();
  60                         execvp(argv[0], argv);
  61                         fprintf(stderr, "dwm: execvp %s", argv[0]);
  62                         perror(" failed");
  63                 }
  64                 exit (0);
  65         }
  66         wait(0);
  67 }