[patch] qmail-queue modified patch

qmail-queue-custom-error.patch (text/plain), 4.06 KB, created by Andrea Cerrito on 2006-10-21 11:53:48 UTC

WARNING, NEW BEHAVIOUR: The patch is using descriptor 4 instead of
STDERR now!

Adds the possibility for a qmail-queue-replacement to offer custom
error (=bounce) messages.

You have to write the error message to filedescriptor 4 and exit 82,
in order to use the custom message. Format of the message:

Dthis is a custom fatal error message
Zthis is a custom temporary failure message

Thanks to Richard Lyons <frob-qmail webcentral.com.au> for spotting a
wrong errstr declaration.

Thanks to Jeremy Hinton for noting that I forget to include the patch to
qmail.h

This patch has been made by Flavio Curti <fcu-software at no-way.org> and is
provided AS IS. Do with it as you wish, I'm not responsible for anything that
breaks because of this patch.

EXAMPLES

Perl:
open(FD,">&4");
print FD "Ztemporary failure message";
close(FD);
exit(82);

Shell:
echo -n "Zpermanent failure after data" >&4
exit 82;

C (non-djb-style):
#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>

char    err[] = "Zpermanently refusing";

int main() {
        write(4,err,(strlen(err)+1));
        exit(82);
}

--- qmail.h     1998-06-15 12:53:16.000000000 +0200
+++ ../../qmail-1.03/qmail.h    2004-05-26 14:48:23.000000000 +0200
@@ -8,6 +8,7 @@
   unsigned long pid;
   int fdm;
   int fde;
+  int fderr;
   substdio ss;
   char buf[1024];
 } ;
*** qmail.c_beforepatch Sat Oct 21 20:36:41 2006
--- qmail.c     Sat Oct 21 20:38:41 2006
*************** struct qmail *qq;
*** 23,44 ****
--- 23,55 ----
  {
    int pim[2];
    int pie[2];
+   int pierr[2];

    setup_qqargs();

    if (pipe(pim) == -1) return -1;
    if (pipe(pie) == -1) { close(pim[0]); close(pim[1]); return -1; }
+   if (pipe(pierr) == -1) {
+     close(pim[0]); close(pim[1]);
+     close(pie[0]); close(pie[1]);
+     close(pierr[0]); close(pierr[1]);
+     return -1;
+   }
+

    switch(qq->pid = vfork()) {
      case -1:
+       close(pierr[0]); close(pierr[1]);
        close(pim[0]); close(pim[1]);
        close(pie[0]); close(pie[1]);
        return -1;
      case 0:
        close(pim[1]);
        close(pie[1]);
+       close(pierr[0]); /* we want to receive data */
        if (fd_move(0,pim[0]) == -1) _exit(120);
        if (fd_move(1,pie[0]) == -1) _exit(120);
+       if (fd_move(4,pierr[1]) == -1) _exit(120);
        if (chdir(auto_qmail) == -1) _exit(61);
        execv(*binqqargs,binqqargs);
        _exit(120);
*************** struct qmail *qq;
*** 46,51 ****
--- 57,63 ----

    qq->fdm = pim[1]; close(pim[0]);
    qq->fde = pie[1]; close(pie[0]);
+   qq->fderr = pierr[0]; close(pierr[1]);
    substdio_fdbuf(&qq->ss,write,qq->fdm,qq->buf,sizeof(qq->buf));
    qq->flagerr = 0;
    return 0;
*************** struct qmail *qq;
*** 93,102 ****
--- 105,126 ----
  {
    int wstat;
    int exitcode;
+   int match;
+   char ch;
+   static char errstr[256];
+   int len = 0;

    qmail_put(qq,"",1);
    if (!qq->flagerr) if (substdio_flush(&qq->ss) == -1) qq->flagerr = 1;
    close(qq->fde);
+   substdio_fdbuf(&qq->ss,read,qq->fderr,qq->buf,sizeof(qq->buf));
+   while( substdio_bget(&qq->ss,&ch,1) && len < 255){
+     errstr[len]=ch;
+     len++;
+   }
+   if (len > 0) errstr[len]='\0'; /* add str-term */
+
+   close(qq->fderr);

    if (wait_pid(&wstat,qq->pid) != qq->pid)
      return "Zqq waitpid surprise (#4.3.0)";
*************** struct qmail *qq;
*** 129,136 ****
      case 81: return "Zqq internal bug (#4.3.0)";
      case 120: return "Zunable to exec qq (#4.3.0)";
      default:
        if ((exitcode >= 11) && (exitcode <= 40))
!       return "Dqq permanent problem (#5.3.0)";
        return "Zqq temporary problem (#4.3.0)";
    }
  }
--- 153,163 ----
      case 81: return "Zqq internal bug (#4.3.0)";
      case 120: return "Zunable to exec qq (#4.3.0)";
      default:
+       if (exitcode == 82 && len > 2){
+         return errstr;
+       }
        if ((exitcode >= 11) && (exitcode <= 40))
!         return "Dqq permanent problem (#5.3.0)";
        return "Zqq temporary problem (#4.3.0)";
    }
  }