From 572c3e1a583138fa60ee56fc689f4fc126e93176 Mon Sep 17 00:00:00 2001
From: Roy Marples <roy@marples.name>
Date: Sun, 23 Feb 2025 20:23:45 +0000
Subject: [PATCH] Add nosyslog

Fixes #472.
---
 src/dhcpcd.c         |  3 ---
 src/dhcpcd.conf.5.in |  6 ++++--
 src/if-options.c     | 11 ++++++++++-
 src/if-options.h     |  3 ++-
 src/logerr.c         |  5 ++++-
 src/script.c         |  2 +-
 6 files changed, 21 insertions(+), 9 deletions(-)

diff --git a/src/dhcpcd.c b/src/dhcpcd.c
index 09c3da24..4a2c0184 100644
--- a/src/dhcpcd.c
+++ b/src/dhcpcd.c
@@ -2173,9 +2173,6 @@ main(int argc, char **argv, char **envp)
 	ctx.options &= ~DHCPCD_DAEMONISE;
 #endif
 
-	if (ctx.options & DHCPCD_DEBUG)
-		logsetopts(logopts | LOGERR_DEBUG);
-
 	if (!(ctx.options & (DHCPCD_TEST | DHCPCD_DUMPLEASE))) {
 printpidfile:
 		/* If we have any other args, we should run as a single dhcpcd
diff --git a/src/dhcpcd.conf.5.in b/src/dhcpcd.conf.5.in
index a67c68f7..c8a0f62a 100644
--- a/src/dhcpcd.conf.5.in
+++ b/src/dhcpcd.conf.5.in
@@ -1,6 +1,6 @@
 .\" SPDX-License-Identifier: BSD-2-Clause
 .\"
-.\" Copyright (c) 2006-2024 Roy Marples
+.\" Copyright (c) 2006-2025 Roy Marples
 .\" All rights reserved
 .\"
 .\" Redistribution and use in source and binary forms, with or without
@@ -24,7 +24,7 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.Dd November 1, 2024
+.Dd February 23, 2025
 .Dt DHCPCD.CONF 5
 .Os
 .Sh NAME
@@ -576,6 +576,8 @@ Don't solicit or accept IPv6 Router Advertisements.
 .It Ic nolink
 Don't receive link messages about carrier status.
 You should only set this for buggy interface drivers.
+.It Ic nosyslog
+Disable writing to syslog(3).
 .It Ic noup
 Don't bring the interface up when in manager mode.
 .It Ic option Ar option
diff --git a/src/if-options.c b/src/if-options.c
index d931c36e..dd05072e 100644
--- a/src/if-options.c
+++ b/src/if-options.c
@@ -174,6 +174,7 @@ const struct option cf_options[] = {
 	{"request_time",    required_argument, NULL, O_REQUEST_TIME},
 	{"fallback_time",   required_argument, NULL, O_FALLBACK_TIME},
 	{"ipv4ll_time",     required_argument, NULL, O_IPV4LL_TIME},
+	{"nosyslog",        no_argument,       NULL, O_NOSYSLOG},
 	{NULL,              0,                 NULL, '\0'}
 };
 
@@ -740,7 +741,7 @@ parse_option(struct dhcpcd_ctx *ctx, const char *ifname, struct if_options *ifo,
 		}
 		break;
 	case 'd':
-		ifo->options |= DHCPCD_DEBUG;
+		logsetopts(loggetopts() | LOGERR_DEBUG);
 		break;
 	case 'e':
 		ARG_REQUIRED;
@@ -2548,6 +2549,14 @@ invalid_token:
 		}
 		break;
 #endif
+	case O_NOSYSLOG:
+		{
+			unsigned int logopts = loggetopts();
+
+			logopts &= ~LOGERR_LOG;
+			logsetopts(logopts);
+		}
+		break;
 	default:
 		return 0;
 	}
diff --git a/src/if-options.h b/src/if-options.h
index cd02be18..6fa178fc 100644
--- a/src/if-options.h
+++ b/src/if-options.h
@@ -63,7 +63,7 @@
 #define DHCPCD_RTBUILD			(1ULL << 2)
 #define DHCPCD_GATEWAY			(1ULL << 3)
 #define DHCPCD_STATIC			(1ULL << 4)
-#define DHCPCD_DEBUG			(1ULL << 5)
+//#define DHCPCD_DEBUG			(1ULL << 5)
 #define DHCPCD_ARP_PERSISTDEFENCE	(1ULL << 6)
 #define DHCPCD_LASTLEASE		(1ULL << 7)
 #define DHCPCD_INFORM			(1ULL << 8)
@@ -189,6 +189,7 @@
 #define O_IPV4LL_TIME		O_BASE + 56
 #define O_VSIO			O_BASE + 57
 #define O_VSIO6			O_BASE + 58
+#define O_NOSYSLOG		O_BASE + 59
 
 extern const struct option cf_options[];
 
diff --git a/src/logerr.c b/src/logerr.c
index 3e5cd835..7520c56a 100644
--- a/src/logerr.c
+++ b/src/logerr.c
@@ -427,6 +427,8 @@ logsetopts(unsigned int opts)
 
 	ctx->log_opts = opts;
 	setlogmask(LOG_UPTO(opts & LOGERR_DEBUG ? LOG_DEBUG : LOG_INFO));
+	if (!(ctx->log_opts & LOGERR_LOG))
+		closelog();
 }
 
 #ifdef LOGERR_TAG
@@ -463,7 +465,8 @@ logopen(const char *path)
 
 	if (ctx->log_opts & LOGERR_LOG_PID)
 		opts |= LOG_PID;
-	openlog(getprogname(), opts, LOGERR_SYSLOG_FACILITY);
+	if (ctx->log_opts & LOGERR_LOG)
+		openlog(getprogname(), opts, LOGERR_SYSLOG_FACILITY);
 	if (path == NULL)
 		return 1;
 
diff --git a/src/script.c b/src/script.c
index 3ee2eaa4..b06e2141 100644
--- a/src/script.c
+++ b/src/script.c
@@ -471,7 +471,7 @@ make_env(struct dhcpcd_ctx *ctx, const struct interface *ifp,
 		if (efprintf(fp, "af_waiting=%d", af) == -1)
 			goto eexit;
 	}
-	if (ifo->options & DHCPCD_DEBUG) {
+	if (loggetopts() & LOGERR_DEBUG) {
 		if (efprintf(fp, "syslog_debug=true") == -1)
 			goto eexit;
 	}
-- 
2.47.3