src/osdep_darwin.c

   1
   2 #include <sys/types.h>
   3 #include <sys/sysctl.h>
   4
   5 #include <assert.h>
   6 #include <stdlib.h>
   7 #include <string.h>
   8
   9 #include <WINGs/WUtil.h>
  10
  11 #include "wconfig.h"
  12 #include "osdep.h"
  13
  14 /*
  15  * copy argc and argv for an existing process identified by `pid'
  16  * into suitable storage given in ***argv and *argc.
  17  *
  18  * subsequent calls use the same static area for argv and argc.
  19  *
  20  * returns 0 for failure, in which case argc := 0 and argv := NULL
  21  * returns 1 for success
  22  */
  23 Bool GetCommandForPid(int pid, char ***argv, int *argc)
  24 #ifdef KERN_PROCARGS2
  25 {
  26         int j, mib[4];
  27         unsigned int i, idx;
  28         size_t count;
  29         static char *args = NULL;
  30         static int argmax = 0;
  31
  32         *argv = NULL;
  33         *argc = 0;
  34
  35         /* the system-wide limit */
  36         if (argmax == 0) { /* it hopefully doesn't change at runtime *g* */
  37                 mib[0] = CTL_KERN;
  38                 mib[1] = KERN_ARGMAX;
  39                 mib[2] = 0;
  40                 mib[3] = 0;
  41
  42                 count = sizeof(argmax);
  43                 if (sysctl(mib, 2, &argmax, &count, NULL, 0) == -1)
  44                         return False;
  45         }
  46
  47         /* if argmax is still 0, something went very seriously wrong */
  48         assert(argmax > 0);
  49
  50         /* space for args; no need to free before returning even on errors */
  51         if (args == NULL)
  52                 args = (char *)wmalloc(argmax);
  53
  54         /* get process args */
  55         mib[0] = CTL_KERN;
  56         mib[1] = KERN_PROCARGS2;
  57         mib[2] = pid;
  58
  59         count = argmax;
  60         if (sysctl(mib, 3, args, &count, NULL, 0) == -1 || count == 0)
  61                 return False;
  62
  63         /* get argc, skip */
  64         memcpy(argc, args, sizeof(*argc));
  65         idx = sizeof(*argc);
  66
  67         while (args[idx++] != '\0')             /* skip execname */
  68                 ;
  69         while (args[idx] == '\0')               /* padding too */
  70                 idx++;
  71         /* args[idx] is at at begininng of args now */
  72
  73         *argv = (char **)wmalloc(sizeof(char *) * (*argc + 1 /* term. null ptr */));
  74         (*argv)[0] = args + idx;
  75
  76         /* go through args, set argv[$next] to the beginning of each string */
  77         for (i = 0, j = 1; i < count - idx /* do not overrun */; i++) {
  78                 if (args[idx + i] != '\0')
  79                         continue;
  80                 if (args[idx + i] == '\0')
  81                         (*argv)[j++] = &args[idx + i + 1];
  82                 if (j == *argc)
  83                         break;
  84         }
  85
  86         /* the list of arguments must be terminated by a null pointer */
  87         (*argv)[j] = NULL;
  88         return True;
  89 }
  90 #else /* !KERN_PROCARGS2 */
  91 {
  92         *argv = NULL;
  93         *argc = 0;
  94
  95         return False;
  96 }
  97 #endif