Reread .fetchmailrc when it's changed in daemon mode.

svn path=/trunk/; revision=2674

4 files changed, 63 insertions, 14 deletions

diff --git a/NEWS b/NEWS
index a4efe245..935ddba6 100644
--- a/NEWS
+++ b/NEWS
@@ -9,6 +9,8 @@ a Certifying Authority we recognize?).
 
 (The `lines' figures total .c, .h, .l, and .y files under version control.)
 
+* Arrange for fetchmail to restart itself quietly when the rc file is touched.
+
 fetchmail-5.2.1 (Sun Dec 19 23:08:53 EST 1999), 18330 lines:
 * Added FAQ item R10 on timeouts during messages.
 * Fixed indentation problem in fetchmailconf.
diff --git a/fetchmail-features.html b/fetchmail-features.html
index 68d745f8..4f24b622 100644
--- a/fetchmail-features.html
+++ b/fetchmail-features.html
@@ -10,7 +10,7 @@
 <table width="100%" cellpadding=0><tr>
 <td width="30%">Back to <a href="index.html">Fetchmail Home Page</a>
 <td width="30%" align=center>To <a href="/~esr/sitemap.html">Site Map</a>
-<td width="30%" align=right>$Date: 1999/12/19 20:11:48 $
+<td width="30%" align=right>$Date: 1999/12/21 03:45:26 $
 </table>
 <HR>
 
@@ -18,6 +18,10 @@
 
 <H2>Since 5.0:</H2>
 <UL>
+<LI>
+Fetchmail running in daemon mode now restarts itself quietly when the
+rc file is touched.
+
 <LI>Following recent court decisions and changes in U.S. federal
 regulatory policy, hooks for Secure Sockets Layer (SSL) are now part
 of the main fetchmail distribution.  The distribution still contains
@@ -184,7 +188,7 @@ get-mail, gwpop, pimp-1.0, pop-perl5-1.2, popc, popmail-1.6 and upop.<P>
 <table width="100%" cellpadding=0><tr>
 <td width="30%">Back to <a href="index.html">Fetchmail Home Page</a>
 <td width="30%" align=center>To <a href="/~esr/sitemap.html">Site Map</a>
-<td width="30%" align=right>$Date: 1999/12/19 20:11:48 $
+<td width="30%" align=right>$Date: 1999/12/21 03:45:26 $
 </table>
 
 <P><ADDRESS>Eric S. Raymond <A HREF="mailto:esr@thyrsus.com">&lt;esr@snark.thyrsus.com&gt;</A></ADDRESS>
diff --git a/fetchmail.c b/fetchmail.c
index f491e92e..174e80b6 100644
--- a/fetchmail.c
+++ b/fetchmail.c
@@ -83,6 +83,7 @@ static char *lockfile;		/* name of lockfile */
 static int querystatus;		/* status of query */
 static int successes;		/* count number of successful polls */
 static struct runctl cmd_run;	/* global options set from command line */
+static time_t parsetime;	/* time of last parse */
 
 static void termhook(int);		/* forward declaration of exit hook */
 
@@ -229,9 +230,7 @@ int main(int argc, char **argv)
 	printf("+NETSEC");
 #endif /* NET_SECURITY */
 #ifdef HAVE_SOCKS
-  #if HAVE_SOCKS
 	printf("+SOCKS");
-  #endif
 #endif /* HAVE_SOCKS */
 #if ENABLE_NLS
 	printf("+NLS");
@@ -427,9 +426,13 @@ int main(int argc, char **argv)
 	}
 	else if (argc > 1)
 	{
-	    fprintf(stderr,
-		    _("fetchmail: can't accept options while a background fetchmail is running.\n"));
-	    return(PS_EXCLUDE);
+	    /* this test enables re-execing on a changed rcfile */
+	    if (getpid() != pid)
+	    {
+		fprintf(stderr,
+			_("fetchmail: can't accept options while a background fetchmail is running.\n"));
+		return(PS_EXCLUDE);
+	    }
 	}
 	else if (kill(pid, SIGUSR1) == 0)
 	{
@@ -474,15 +477,13 @@ int main(int argc, char **argv)
 	}
     }
 
-/* Time to initiate the SOCKS library (this is not mandatory: it just
- registers the correct application name for logging purpose. If you
- have some problem, comment these lines). */
+    /*
+     * Time to initiate the SOCKS library (this is not mandatory: it just
+     * registers the correct application name for logging purpose. If you
+     * have some problem, comment out these lines).
+     */
 #ifdef HAVE_SOCKS
-  #if HAVE_SOCKS
-/* Mmmh... I don't like hardcoded application names,
- but "fetchmail" is everywhere... */
     SOCKSinit("fetchmail");
-  #endif
 #endif /* HAVE_SOCKS */
 
     /*
@@ -550,6 +551,24 @@ int main(int argc, char **argv)
      * reflect the status of that transaction.
      */
     do {
+	/* 
+	 * Check to see if the rcfile has been touched.  If so,
+	 * re-exec so the file will be reread.  Doing it this way
+	 * avoids all the complications of trying to deallocate the
+	 * in-core control structures -- and the potential memory
+	 * leaks...
+	 */
+	struct stat	rcstat;
+
+	if (stat(rcfile, &rcstat) == -1)
+	    report(stderr, _("couldn't time-check the run-control file\n"));
+	else if (rcstat.st_mtime > parsetime)
+	{
+	    report(stdout, _("restarting fetchmail (rc file changed)\n"));
+	    execvp("fetchmail", argv);
+	    report(stderr, _("attempt to re-exec fetchmail failed\n"));
+	}
+
 #if defined(HAVE_RES_SEARCH) && defined(USE_TCPIP_FOR_DNS)
 	/*
 	 * This was an efficiency hack that backfired.  The theory
@@ -895,6 +914,7 @@ static int load_params(int argc, char **argv, int optind)
     int	implicitmode, st;
     struct passwd *pw;
     struct query def_opts, *ctl;
+    struct stat rcstat;
 
     run.bouncemail = TRUE;
 
@@ -914,6 +934,12 @@ static int load_params(int argc, char **argv, int optind)
     def_opts.remotename = user;
     def_opts.listener = SMTP_MODE;
 
+    /* note the parse time, so we can pick up on modifications */
+    if (stat(rcfile, &rcstat) == -1)
+	report(stderr, _("couldn't time-check the run-control file\n"));
+    else
+	parsetime = rcstat.st_mtime;
+
     /* this builds the host list */
     if ((st = prc_parse_file(rcfile, !versioninfo)) != 0)
 	exit(st);
diff --git a/fetchmail.man b/fetchmail.man
index 39e58312..edc08fd1 100644
--- a/fetchmail.man
+++ b/fetchmail.man
@@ -842,6 +842,18 @@ fetched (and thus marked seen by the mailserver) but not delivered
 locally due to some transient error, it will be re-fetched during the
 next poll cycle.  (The IMAP logic doesn't delete messages until
 they're delivered, so this problem does not arise.)
+.PP
+If you touch or change the 
+.I .fetchmailrc 
+file while fetchmail is running in daemon mode, this will be detected 
+at the beginning of the next poll cycle.  When a changed
+.I .fetchmailrc 
+is detected, fetchmail rereads it and restarts from scratch (using
+exec(2); no state information is retained in the new instance).  Note also
+that if you break the
+.I .fetchmailrc 
+file's syntax, the new instance will softly and silently vanish away
+on startup.
 
 .SH ADMINISTRATIVE OPTIONS
 .PP
@@ -909,6 +921,11 @@ messages are appended to the end of the mailbox; when this is not true
 it may treat some old messages as new and vice versa.  The only 
 real fix for this problem is to  switch to IMAP.
 .PP
+Yet another POP3 problem is that if they can't make tempfiles in the
+user's home directory, some POP3 servers will hand back an
+undocumented response that causes fetchmail to spuriously report "No
+mail".
+.PP
 The IMAP code uses the presence or absence of the server flag \eSeen
 to decide whether or not a message is new.  Under Unix, it counts on
 your IMAP server to notice the BSD-style Status flags set by mail user