Add a -C, --nohook option to skip the running of hook scripts. Makes it easier to just not do any configuring of resolv.conf

configure.c

@@ -98,6 +98,19 @@ exec_script(const struct options *options, const char *iface,
 			elen += configure_env(env + elen, "new", dhcpn, options);
 		}
 	}
+	/* Add our base environment */
+	if (options->environ) {
+		e = 0;
+		while (options->environ[e++])
+			;
+		env = xrealloc(env, sizeof(char *) * (elen + e + 1));
+		e = 0;
+		while (options->environ[e]) {
+			env[elen + e] = xstrdup(options->environ[e]);
+			e++;
+		}
+		elen += e;
+	}
 	env[elen] = '\0';
 
 	/* OK, we need to block signals */

dhcpcd.8.in

@@ -266,6 +266,13 @@ Here are some option that deal with turning these bits off.
 Don't request or claim the address by ARP.
 .It Fl G , -nogateway
 Don't set any default routes.
+.It Ic nohook Ar script
+Don't run this hook script.
+Matches full name, or prefixed with 2 numbers optionally ending with .sh.
+Example for not running the hook script to configure
+.Pa /etc/resolv.conf :-
+.Nm
+-C resolv.conf
 .It Fl L , -noipv4ll
 Don't use IPv4LL at all.
 .It Fl O , -nooption Ar option

dhcpcd.c

@@ -51,7 +51,7 @@ const char copyright[] = "Copyright (c) 2006-2008 Roy Marples";
 
 /* Don't set any optional arguments here so we retain POSIX
  * compatibility with getopt */
-#define OPTS "c:df:h:i:kl:m:no:pr:s:t:u:xADEF:GI:LO:TV"
+#define OPTS "c:df:h:i:kl:m:no:pr:s:t:u:xAC:DEF:GI:LO:TV"
 
 static int doversion = 0;
 static int dohelp = 0;
@@ -73,6 +73,7 @@ static const struct option longopts[] = {
 	{"userclass",   required_argument,  NULL, 'u'},
 	{"exit",        no_argument,        NULL, 'x'},
 	{"noarp",       no_argument,        NULL, 'A'},
+	{"nohook",	required_argument,  NULL, 'C'},
 	{"duid",        no_argument,        NULL, 'D'},
 	{"lastlease",   no_argument,        NULL, 'E'},
 	{"fqdn",        optional_argument,  NULL, 'F'},
@@ -156,7 +157,48 @@ usage(void)
 	printf("usage: "PACKAGE" [-dknpxADEGHLOSTV] [-c script] [-f file ] [-h hostname]\n"
 	       "              [-i classID ] [-l leasetime] [-m metric] [-o option] [-r ipaddr]\n"
 	       "              [-s ipaddr] [-t timeout] [-u userclass] [-F none|ptr|both]\n"
-	       "              [-I clientID] <interface>\n");
+	       "              [-I clientID] [-C hookscript] <interface>\n");
+}
+
+static char * 
+add_environ(struct options *options, const char *value, int uniq)
+{
+	char **newlist;
+	char **lst = options->environ;
+	size_t i = 0, l, lv;
+	char *match = NULL, *p;
+
+	match = xstrdup(value);
+	p = strchr(match, '=');
+	if (p)
+		*p++ = '\0';
+	l = strlen(match);
+
+	while (lst && lst[i]) {
+		if (match && strncmp(lst[i], match, l) == 0) {
+			if (uniq) {
+				free(lst[i]);
+				lst[i] = xstrdup(value);
+			} else {
+				/* Append a space and the value to it */
+				l = strlen(lst[i]);
+				lv = strlen(p);
+				lst[i] = xrealloc(lst[i], l + lv + 2);
+				lst[i][l] = ' ';
+				memcpy(lst[i] + l + 1, p, lv);
+				lst[i][l + lv + 2] = '\0';
+			}
+			free(match);
+			return lst[i];
+		}
+		i++;
+	}
+
+	newlist = xrealloc(lst, sizeof(char *) * (i + 2));
+	newlist[i] = xstrdup(value);
+	newlist[i + 1] = NULL;
+	options->environ = newlist;
+	return (newlist[i]);
 }
 
 static int
@@ -166,6 +208,7 @@ parse_option(int opt, char *oarg, struct options *options)
 	int i;
 	int j;
 	char *p;
+	size_t s;
 
 	switch(opt) {
 	case 'h':
@@ -282,6 +325,16 @@ parse_option(int opt, char *oarg, struct options *options)
 		/* IPv4LL requires ARP */
 		options->options &= ~DHCPCD_IPV4LL;
 		break;
+	case 'C':
+		/* Commas to spaces for shell */
+		while ((p = strchr(oarg, ',')))
+			*p = ' ';
+		s = strlen("skip_hooks=") + strlen(oarg) + 1;
+		p = xmalloc(sizeof(char) * s);
+		snprintf(p, s, "skip_hooks=%s", oarg);
+		add_environ(options, p, 0);
+		free(p);
+		break;
 	case 'D':
 		options->options |= DHCPCD_DUID;
 		break;
@@ -784,6 +837,12 @@ abort:
 		close(pidfd);
 		unlink(options->pidfile);
 	}
+	if (options->environ) {
+		len = 0;
+		while (options->environ[len])
+			free(options->environ[len++]);
+		free(options->environ);
+	}
 	free(options);
 
 #ifdef THERE_IS_NO_FORK

dhcpcd.conf.5.in

@@ -86,6 +86,13 @@ Don't send any ARP requests.
 This also disables IPv4LL.
 .It Ic nogateway
 Don't install any default routes.
+.It Ic nohook Ar script
+Don't run this hook script.
+Matches full name, or prefixed with 2 numbers optionally ending with .sh.
+Example for not running the hook script to configure
+.Pa /etc/resolv.conf :-
+.Nm dhcpcd
+-C resolv.conf
 .It Ic noipv4ll
 Don't attempt to obtain an IPv4LL address if we failed to get one via DHCP.
 See

dhcpcd.h

@@ -87,6 +87,7 @@ struct options {
 	struct in_addr request_address;
 	struct in_addr request_netmask;
 
+	char **environ;
 	const char *script;
 	char pidfile[PATH_MAX];
 };

dhcpcd.sh.in

@@ -25,6 +25,13 @@ for hook in \
 	@SYSCONFDIR@/dhcpcd.hook \
 	@HOOKDIR@/*
 do
+	for skip in ${skip_hooks}; do
+		case "${hook}" in
+			"${skip}")			continue 2;;
+			*/[0-9][0-9]"-${skip}")		continue 2;;
+			*/[0-9][0-9]"-${skip}.sh")	continue 2;;
+		esac
+	done
 	if [ -f "${hook}" ]; then
 		. "${hook}"
 	fi

hook.d/01-test.sh

@@ -1,6 +1,6 @@
 # Just echo our DHCP options we have
 
 if [ "${reason}" = "TEST" ]; then
-	env | grep "^\(interface\|pid\|reason\)="
+	env | grep "^\(interface\|pid\|reason\|skip_hooks\)="
 	env | grep "^\(new_\|old_\)" | sort
 fi