diplodocus.org Git - nmh/blob - sbr/ext_hook.c

   1 /*
   2  *
   3  *      Run a program that hooks into some other system.  The first argument is
   4  *      name of the hook to use, the second is the full path name of a mail message.
   5  *      The third argument is also the full path name of a mail message, or a NULL
   6  *      pointer if it isn't needed.  Look in the context for an error message if
   7  *      something goes wrong; there is a built-in message in case one isn't specified.
   8  *      Only produce the error message once.
   9  */
  10
  11 #include <h/mh.h>
  12
  13 int
  14 ext_hook(char *hook_name, char *message_file_name_1, char *message_file_name_2)
  15 {
  16     char        *hook;                  /* hook program from context */
  17     pid_t       pid;                    /* ID of child process */
  18     int         status;                 /* exit or other child process status */
  19     char        **vec;                  /* argument vector for child process */
  20     int         vecp;                   /* Vector index */
  21     char        *program;               /* Name of program to execute */
  22
  23     static  int did_message = 0;        /* set if we've already output a message */
  24
  25     if ((hook = context_find(hook_name)) == NULL)
  26         return (OK);
  27
  28     switch (pid = fork()) {
  29     case -1:
  30         status = NOTOK;
  31         advise(NULL, "external database may be out-of-date.");
  32         break;
  33
  34     case 0:
  35         vec = argsplit(hook, &program, &vecp);
  36         vec[vecp++] = message_file_name_1;
  37         vec[vecp++] = message_file_name_2;
  38         vec[vecp++] = NULL;
  39         execvp(program, vec);
  40         advise(program, "Unable to execute");
  41         _exit(-1);
  42         /* NOTREACHED */
  43
  44     default:
  45         status = pidwait(pid, -1);
  46         break;
  47     }
  48
  49     if (status != OK) {
  50         if (did_message == 0) {
  51             char *msghook;
  52             if ((msghook = context_find("msg-hook")) != NULL)
  53                 advise(NULL, msghook);
  54             else {
  55                 char errbuf[BUFSIZ];
  56                 snprintf(errbuf, sizeof(errbuf), "external hook \"%s\"", hook);
  57                 pidstatus(status, stderr, errbuf);
  58             }
  59             did_message = 1;
  60         }
  61
  62         return (NOTOK);
  63     }
  64
  65     else
  66         return (OK);
  67 }