dma-mbox-create: add error/status logging

diff --git a/dma-mbox-create.c b/dma-mbox-create.c
index b79510e34f7c67abe727669cf29ed39a29e14849..c84652b74d47afa6347b6a53a5bbc965d60a00ba 100644 (file)
--- a/dma-mbox-create.c
+++ b/dma-mbox-create.c
@@ -41,15 +41,41 @@
 #include <sys/param.h>
 #include <sys/stat.h>
 
+#include <errno.h>
 #include <fcntl.h>
 #include <grp.h>
 #include <paths.h>
 #include <pwd.h>
 #include <stdio.h>
+#include <syslog.h>
 #include <unistd.h>
 
 #include "dma.h"
 
+
+static void
+logfail(const char *fmt, ...)
+{
+       int oerrno = errno;
+       va_list ap;
+       char outs[1024];
+
+       outs[0] = 0;
+       if (fmt != NULL) {
+               va_start(ap, fmt);
+               vsnprintf(outs, sizeof(outs), fmt, ap);
+               va_end(ap);
+       }
+
+       errno = oerrno;
+       if (*outs != 0)
+               syslog(LOG_ERR, errno ? "%s: %m" : "%s", outs);
+       else
+               syslog(LOG_ERR, errno ? "%m" : "unknown error");
+
+       exit(1);
+}
+
 /*
  * Create a mbox in /var/mail for a given user, or make sure
  * the permissions are correct for dma.
@@ -67,50 +93,68 @@ main(int argc, char **argv)
        char fn[PATH_MAX+1];
        int f;
 
+       openlog("dma-mbox-create", 0, LOG_MAIL);
+
+       errno = 0;
+       gr = getgrnam(DMA_GROUP);
+       if (!gr)
+               logfail("cannot find dma group `%s'", DMA_GROUP);
+
+       mail_gid = gr->gr_gid;
+
+       if (setgid(mail_gid) != 0)
+               logfail("cannot set gid to %d (%s)", mail_gid, DMA_GROUP);
+       if (getegid() != mail_gid)
+               logfail("cannot set gid to %d (%s), still at %d", mail_gid, DMA_GROUP, getegid());
+
        /*
         * We take exactly one argument: the username.
         */
-       if (argc != 2)
-               return (1);
+       if (argc != 2) {
+               errno = 0;
+               logfail("no arguments");
+       }
        user = argv[1];
 
+       syslog(LOG_NOTICE, "creating mbox for `%s'", user);
+
        /* the username may not contain a pathname separator */
-       if (strchr(user, '/'))
-               return (1);
+       if (strchr(user, '/')) {
+               errno = 0;
+               logfail("path separator in username `%s'", user);
+               exit(1);
+       }
 
        /* verify the user exists */
+       errno = 0;
        pw = getpwnam(user);
        if (!pw)
-               return (1);
+               logfail("cannot find user `%s'", user);
 
        user_uid = pw->pw_uid;
 
-       gr = getgrnam(DMA_GROUP);
-       if (!gr)
-               return (1);
-
-       mail_gid = gr->gr_gid;
-
-       if (setgid(mail_gid) != 0)
-               return (1);
-       if (getegid() != mail_gid)
-               return (1);
-
        error = snprintf(fn, sizeof(fn), "%s/%s", _PATH_MAILDIR, user);
-       if (error < 0 || (size_t)error >= sizeof(fn))
-               return (1);
+       if (error < 0 || (size_t)error >= sizeof(fn)) {
+               if (error >= 0) {
+                       errno = 0;
+                       logfail("mbox path too long");
+               }
+               logfail("cannot build mbox path for `%s/%s'", _PATH_MAILDIR, user);
+       }
 
        f = open(fn, O_RDONLY|O_CREAT, 0600);
        if (f < 0)
-               return (1);
+               logfail("cannot open mbox `%s'", fn);
 
        if (fchown(f, user_uid, mail_gid))
-               return (1);
+               logfail("cannot change owner of mbox `%s'", fn);
 
        if (fchmod(f, 0620))
-               return (1);
+               logfail("cannot change permissions of mbox `%s'", fn);
 
        /* file should be present with the right owner and permissions */
 
+       syslog(LOG_NOTICE, "successfully created mbox for `%s'", user);
+
        return (0);
 }