From 218a0325571c9f000fd86dda47f0d50a68005df2 Mon Sep 17 00:00:00 2001
From: Joachim Wiberg <troglobit@gmail.com>
Date: Sat, 22 Apr 2023 08:48:32 +0200
Subject: [PATCH] Fix #61: add support for `-c` and `-cc` to disable log
 compression

This patch imports the FreeBSD meaning to the `-c` command line option.
It disables "last message repeated" style log compression for repeated
log messages.  A single `-c` disables compression for pipes, another
`-c` (-cc works) also disables compression for all other log targets.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
---
 man/syslogd.8 |  8 +++++++-
 src/syslogd.c | 10 ++++++++--
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/man/syslogd.8 b/man/syslogd.8
index c535242..9a93b8f 100644
--- a/man/syslogd.8
+++ b/man/syslogd.8
@@ -38,7 +38,7 @@
 .Nd log systems messages
 .Sh SYNOPSIS
 .Nm
-.Op Fl ?468AdFHKknsTtv
+.Op Fl ?468AcdFHKknsTtv
 .Op Fl a Ar addr[/len][:port]
 .Op Fl a Ar name[:port]
 .Op Fl b Ar addr[:port]
@@ -245,6 +245,12 @@ relies on this file being removed at system reboot.  The default
 location depends on the system and how
 .Nm
 was configured.
+.It Fl c
+Disable the compression of repeated instances of the same line into a
+single line of the form
+.Dq Li "last message repeated N times"
+when the output is a pipe to another program.  If specified twice,
+disable this compression in all cases.
 .It Fl d
 Put
 .Nm
diff --git a/src/syslogd.c b/src/syslogd.c
index f32c8b1..bd02756 100644
--- a/src/syslogd.c
+++ b/src/syslogd.c
@@ -144,6 +144,7 @@ static int	  MarkInterval = 20 * 60; /* interval between marks in seconds */
 static int	  family = PF_UNSPEC;	  /* protocol family (IPv4, IPv6 or both) */
 static int	  mask_C1 = 1;		  /* mask characters from 0x80 - 0x9F */
 static int	  send_to_all;		  /* send message to all IPv4/IPv6 addresses */
+static int	  no_compress;		  /* don't compress messages (1=pipes, 2=all) */
 static int	  secure_opt;		  /* sink for others, log to remote, or only unix domain socks */
 static int	  secure_mode;		  /* same as above but from syslog.conf, only if cmdline unset */
 
@@ -396,7 +397,7 @@ int main(int argc, char *argv[])
 	char *ptr;
 	int ch;
 
-	while ((ch = getopt(argc, argv, "468Aa:b:C:dHFf:Kkm:nP:p:r:sTtv?")) != EOF) {
+	while ((ch = getopt(argc, argv, "468Aa:b:C:cdHFf:Kkm:nP:p:r:sTtv?")) != EOF) {
 		switch ((char)ch) {
 		case '4':
 			family = PF_INET;
@@ -434,6 +435,10 @@ int main(int argc, char *argv[])
 			CacheFile = optarg;
 			break;
 
+		case 'c':
+			no_compress++;
+			break;
+
 		case 'd': /* debug */
 			Debug = 1;
 			Foreground = 1;
@@ -1680,7 +1685,8 @@ static void logmsg(struct buf_msg *buffer)
 		/*
 		 * suppress duplicate lines to this file
 		 */
-		if ((buffer->flags & MARK) == 0 && savedlen == f->f_prevlen &&
+		if (no_compress - (f->f_type != F_PIPE) < 1 &&
+		    (buffer->flags & MARK) == 0 && savedlen == f->f_prevlen &&
 		    !strcmp(saved, f->f_prevline)) {
 			f->f_lasttime = buffer->timestamp;
 			f->f_prevcount++;