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