autofs-5.0.6 - remove empty command line arguments

From: Ian Kent <raven@themaw.net>

When invoking the automount daemon from a systemd unit file a macro
that evaluates to the empty string is passed as an empty argument
unlike the shell environment within which unquoted arguments are
seen as white space and are not passed at all.

These empty arguments confuse getopt(3) and cause the program
parameters to be misread so we need to remove them before calling
getopt(3).
---

 CHANGELOG          |    1 +
 daemon/automount.c |   39 +++++++++++++++++++++++++++++++++++----
 2 files changed, 36 insertions(+), 4 deletions(-)


--- autofs-5.0.6.orig/CHANGELOG
+++ autofs-5.0.6/CHANGELOG
@@ -18,6 +18,7 @@
 - fix ipv6 configure check.
 - add piddir to configure.
 - add systemd unit support.
+- remove empty command line arguments (passed by systemd).
 
 28/06/2011 autofs-5.0.6
 -----------------------
--- autofs-5.0.6.orig/daemon/automount.c
+++ autofs-5.0.6/daemon/automount.c
@@ -1865,6 +1865,34 @@ static int convert_log_priority(char *pr
 	return -1;
 }
 
+static void remove_empty_args(char **argv, int *argc)
+{
+	int next_to_last = *argc - 1;
+	int i, j;
+
+	for (i = j = 1; i < *argc; i++) {
+		if (*argv[i]) {
+			j++;
+			continue;
+		}
+
+		while (i < *argc && argv[i] && !*argv[i]) i++;
+
+		if (i == *argc)
+			break;
+
+		if (i == next_to_last) {
+			if (*argv[i])
+				argv[j++] = argv[i];
+			break;
+		} else {
+			argv[j++] = argv[i];
+			argv[i--] = "";
+		}
+	}
+	*argc = j;
+}
+
 int main(int argc, char *argv[])
 {
 	int res, opt, status;
@@ -1874,6 +1902,7 @@ int main(int argc, char *argv[])
 	time_t timeout;
 	time_t age = time(NULL);
 	struct rlimit rlim;
+	const char *options = "+hp:t:vmdD:fVrO:l:n:CF";
 	static const struct option long_options[] = {
 		{"help", 0, 0, 'h'},
 		{"pid-file", 1, 0, 'p'},
@@ -1918,8 +1947,10 @@ int main(int argc, char *argv[])
 	dumpmaps = 0;
 	daemon_check = 1;
 
+	remove_empty_args(argv, &argc);
+
 	opterr = 0;
-	while ((opt = getopt_long(argc, argv, "+hp:t:vmdD:fVrO:l:n:CF", long_options, NULL)) != EOF) {
+	while ((opt = getopt_long(argc, argv, options, long_options, NULL)) != EOF) {
 		switch (opt) {
 		case 'h':
 			usage();
@@ -2066,7 +2097,7 @@ int main(int argc, char *argv[])
 	res = setrlimit(RLIMIT_NOFILE, &rlim);
 	if (res)
 		printf("%s: can't increase open file limit - continuing",
-			argv[0]);
+			program);
 
 #if ENABLE_CORES
 	rlim.rlim_cur = RLIM_INFINITY;
@@ -2074,7 +2105,7 @@ int main(int argc, char *argv[])
 	res = setrlimit(RLIMIT_CORE, &rlim);
 	if (res)
 		printf("%s: can't increase core file limit - continuing",
-			argv[0]);
+			program);
 #endif
 
 	if (argc == 0)
@@ -2097,7 +2128,7 @@ int main(int argc, char *argv[])
 		nc = cache_init_null_cache(master_list);
 		if (!nc) {
 			printf("%s: failed to init null map cache for %s",
-				master_list->name, argv[0]);
+				program, master_list->name);
 			exit(1);
 		}
 		master_list->nc = nc;