Reintroduce per command intervals

ChangeLog

@@ -1,3 +1,9 @@
+Release 2.2.0
+=============
+
+2016-10-26 Bernhard Bablok (mail@bablokb.de)
+* re-introduce per command interval configuration variables
+
 Release 2.1.1
 =============
 

README

@@ -40,6 +40,8 @@ Copyright (C) 2009-2013 Peter Marschall <peter@adpm.de>
 - rename to fetchmail_wakeup.c
 - configuration via dovecot.config
 
+Copyright (C) 2016-2016 Bernhard Bablok <mail@bablokb.de>
+- re-introduced per command rate-limits
 
 License
 -------
@@ -76,6 +78,17 @@ Installation of the plugin is essentially a 3-step process:
 That's it.
 
 
+Shortcut Installation for Raspbian
+----------------------------------
+
+Raspbian users will find a precompiled version of the plugin in the
+directory `contrib/release-raspbian`. The plugin was compiled running
+Raspbian Jessie. Just copy the plugin-file to the directory
+`/usr/lib/dovecot/modules/`. A sample configuration-file
+is in `example-config/conf.d/90-fetchmail_wakeup.conf` und should go
+into `/etc/dovecot/conf.d/`.
+
+
 Configuration
 -------------
 After the plugin library is installed and ready to be used, Dovecot's
@@ -103,8 +116,13 @@ This is a 2-step process:
 
    fetchmail_wakeup supports six configuration options:
    - fetchmail_interval = NUMBER
-     Set minimal interval between two fetchmail invocations to NUMBER seconds.
+     Set global minimal interval between two fetchmail invocations
+     to NUMBER seconds.
      If it is not given, the interval defaults to 60.
+   - fetchmail_interval_COMMAND = NUMBER
+     Set minimal interval between two fetchmail invocations
+     for COMMAND to NUMBER seconds.
+     If it is not given, the interval defaults to the global fetchmail_interval.
    - fetchmail_helper = COMMAND
      Execute COMMAND to either start fetchmail (or any other mail fetching tool),
      or to awaken a running fetchmail daemon (or any other mail fetching tool).
@@ -123,6 +141,7 @@ This is a 2-step process:
         # minimal interval (in seconds) between two awakenings of fetchmail
         # (this setting is optional and defaults to 60)
         fetchmail_interval = 60
+        fetchmail_interval_NOOP = 600
 
         # a helper program to notify fetchmail accordingly
         fetchmail_helper = /usr/bin/awaken-fetchmail

example-config/conf.d/90-fetchmail_wakeup.conf

@@ -6,10 +6,17 @@
 # by adding it to the mail_plugins= settings.
 
 plugin {
-	# Set minimal interval between two fetchmail invocations to NUMBER seconds.
+	# Set global minimal interval between two fetchmail invocations to NUMBER seconds.
 	# If it is not given, the interval defaults to 60.
 	fetchmail_interval = 60
 
+	# Set command-specific minimal interval between two fetchmail
+        # invocations to NUMBER seconds. This interval defaults to
+	# fetchmail_interval (global default).
+	# fetchmail_interval_IDLE = 600
+	# fetchmail_interval_STATUS = 600
+	fetchmail_interval_NOOP = 600
+
 	# Execute COMMAND to either start fetchmail (or any other mail fetching tool),
 	# or to awaken a running fetchmail daemon (or any other mail fetching tool).
 	# This setting is used when a system-wide deamon is used to fetch mails.

fetchmail_wakeup.7.in

@@ -1,5 +1,6 @@
 .\" manual page for fetchmail_wakeup
 .\" Copyright (C) 2009-2013 Peter Marschall <peter@adpm.de>
+.\" Copyright (C) 2016-2016 Bernhard Bablok (mail@bablokb.de>
 .\"
 .\" This program is free software; you can redistribute it and/or modify
 .\" it under the terms of the GNU General Public License as published by
@@ -15,7 +16,7 @@
 .\" with this program; if not, write to the Free Software Foundation, Inc.,
 .\" 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 .\"
-.TH FETCHMAIL_WAKEUP 7 "21 May 2011" "" "Dovecot Plugins"
+.TH FETCHMAIL_WAKEUP 7 "21 May 2016" "" "Dovecot Plugins"
 
 .SH NAME
 fetchmail_wakeup \- Dovecot plugin to trigger fetchmail wakeups
@@ -81,12 +82,28 @@ extending the mail_plugins variable by the plugin's name "fetchmail_wakeup"
 Then, set the plugin's configuration options.
 This is done in dovecot.conf's \fBplugin\fP section.
 
-fetchmail_wakeup supports six configuration options:
+fetchmail_wakeup supports nine configuration options:
 .TP
 .BR fetchmail_interval = \fINUMBER\fP
-Set minimal interval between two fetchmail invocations to \fINUMBER\fP seconds.
+Set global minimal interval between two fetchmail invocations
+to \fINUMBER\fP seconds.
 If it is not given, the interval defaults to \fB60\fP.
 .TP
+.BR fetchmail_interval_STATUS = \fINUMBER\fP
+Set minimal interval between two fetchmail invocations for STATUS
+to \fINUMBER\fP seconds.
+If it is not given, the interval defaults to \fBfetchmail_interval\fP.
+.TP
+.BR fetchmail_interval_IDLE = \fINUMBER\fP
+Set minimal interval between two fetchmail invocations for IDLE
+to \fINUMBER\fP seconds.
+If it is not given, the interval defaults to \fBfetchmail_interval\fP.
+.TP
+.BR fetchmail_interval_NOOP = \fINUMBER\fP
+Set minimal interval between two fetchmail invocations for NOOP
+to \fINUMBER\fP seconds.
+If it is not given, the interval defaults to \fBfetchmail_interval\fP.
+.TP
 .BR fetchmail_helper = \fICOMMAND\fP
 Execute \fICOMMAND\fP to either start fetchmail (or any other mail fetching tool),
 or to awaken a running fetchmail daemon (or any other mail fetching tool).

fetchmail_wakeup.c

@@ -45,21 +45,34 @@ typedef    void   handler_t;
 
 /* data structure for commands to be overridden */
 struct overrides {
-	const char *name;		/* the IMAPv4 command name */
-	struct command orig_cmd;	/* copy of the original command's data structure */
+  const char *name;		/* the IMAPv4 command name */
+  struct command orig_cmd;	/* copy of the original command's data structure */
+  struct timeval last;          /* last time this command was executed */
 };
 
 
 /* commands that can be overridden */
 static struct overrides cmds[] = {
-	{ "IDLE",   {} },
-	{ "NOOP",   {} },
-	{ "STATUS", {} },
-	{ "NOTIFY", {} },
-	{ NULL,     {} }
+  { "IDLE",   {}, {} },
+  { "NOOP",   {}, {} },
+  { "STATUS", {}, {} },
+  { "NOTIFY", {}, {} },
+  { NULL,     {}, {} }
 };
 
 
+/* get the index of the given command in cmds[] */
+
+static int get_cmd_index(const char* name) {
+  int i=0;
+  for (i = 0; cmds[i].name != NULL; i++) {
+    if (strcasecmp(cmds[i].name,name) == 0) {
+      return i;
+    }
+  }
+  return i;
+}
+
 /*
  * Get a interval value from config and parse it into a number (with fallback for failures)
  */
@@ -86,22 +99,24 @@ static long getenv_interval(struct mail_user *user, const char *name, long fallb
 /*
  * Don't bother waking up fetchmail too often
  */
-static bool ratelimit(long interval)
+static bool ratelimit(long interval, const char* name)
 {
-	static struct timeval last_one;
+	struct timeval last_one;
 	struct timeval now;
+        int cmd_index;
 	long long millisec_delta;
 
 	if (gettimeofday(&now, NULL))
 		return FALSE;
 
+        cmd_index = get_cmd_index(name);
+        last_one = cmds[cmd_index].last;
 	millisec_delta = ((now.tv_sec - last_one.tv_sec) * 1000000LL +
 	                  now.tv_usec - last_one.tv_usec) / 1000LL;
 	if (millisec_delta > interval * 1000LL) {
-		last_one = now;
+		cmds[cmd_index].last = now;
 		return FALSE;
 	}
-
 	return TRUE;
 }
 
@@ -112,7 +127,8 @@ static bool ratelimit(long interval)
 static void fetchmail_wakeup(struct client_command_context *ctx)
 {
 	struct client *client = ctx->client;
-	long fetchmail_interval = FETCHMAIL_INTERVAL;
+	long interval, fetchmail_interval = FETCHMAIL_INTERVAL;
+        char cfg_var[28];
 
 	/* make sure client->user is defined */
 	if (client == NULL || client->user == NULL)
@@ -125,12 +141,17 @@ static void fetchmail_wakeup(struct client_command_context *ctx)
 	/* convert config variable "fetchmail_interval" into a number */
 	fetchmail_interval = getenv_interval(client->user, "fetchmail_interval", FETCHMAIL_INTERVAL);
 
+        /* query per command interval setting */
+        strcpy(cfg_var,"fetchmail_interval_");
+        strncat(cfg_var,ctx->name,6);
+        interval = getenv_interval(client->user,cfg_var,fetchmail_interval);
+
 #if defined(FETCHMAIL_WAKEUP_DEBUG)
-	i_debug("fetchmail_wakeup: interval %ld used for %s.", fetchmail_interval, ctx->name);
+	i_debug("fetchmail_wakeup: interval %ld used for %s.",interval, ctx->name);
 #endif
-
-	if (ratelimit(fetchmail_interval))
-		return;
+        /* limit rate */
+        if (ratelimit(interval,ctx->name))
+          return;
 
 #if defined(FETCHMAIL_WAKEUP_DEBUG)
 	i_debug("fetchmail_wakeup: rate limit passed.");