env: tool: add command line option to input lockfile path

The default lockname is set to /var/lock. This limits the
usage of this application where OS uses different lockfile
location parameter.
For example, In case of android, the default lock
path location is /data.
Hence by providing the command line option to input lockfile
path will be useful to reuse the tool across multiple
operating system.

usage: ./fw_printenv -l <lockfile path>

Signed-off-by: Ravi Babu <ravibabu@ti.com>

tools/env/fw_env.h

@@ -63,6 +63,7 @@ struct env_opts {
 #endif
 	int aes_flag; /* Is AES encryption used? */
 	uint8_t aes_key[AES_KEY_LENGTH];
+	char *lockname;
 };
 
 int parse_aes_key(char *key, uint8_t *bin_key);

tools/env/fw_env_main.c

@@ -46,6 +46,7 @@ static struct option long_options[] = {
 	{"help", no_argument, NULL, 'h'},
 	{"script", required_argument, NULL, 's'},
 	{"noheader", required_argument, NULL, 'n'},
+	{"lock", required_argument, NULL, 'l'},
 	{NULL, 0, NULL, 0}
 };
 
@@ -72,6 +73,7 @@ void usage_printenv(void)
 		" -c, --config         configuration file, default:" CONFIG_FILE "\n"
 #endif
 		" -n, --noheader       do not repeat variable name in output\n"
+		" -l, --lock           lock node, default:/var/lock\n"
 		"\n");
 }
 
@@ -88,6 +90,7 @@ void usage_setenv(void)
 #ifdef CONFIG_FILE
 		" -c, --config         configuration file, default:" CONFIG_FILE "\n"
 #endif
+		" -l, --lock           lock node, default:/var/lock\n"
 		" -s, --script         batch mode to minimize writes\n"
 		"\n"
 		"Examples:\n"
@@ -119,7 +122,7 @@ static void parse_common_args(int argc, char *argv[])
 	env_opts.config_file = CONFIG_FILE;
 #endif
 
-	while ((c = getopt_long(argc, argv, ":a:c:h", long_options, NULL)) !=
+	while ((c = getopt_long(argc, argv, ":a:c:l:h", long_options, NULL)) !=
 	       EOF) {
 		switch (c) {
 		case 'a':
@@ -134,6 +137,9 @@ static void parse_common_args(int argc, char *argv[])
 			env_opts.config_file = optarg;
 			break;
 #endif
+		case 'l':
+			env_opts.lockname = optarg;
+			break;
 		case 'h':
 			do_printenv ? usage_printenv() : usage_setenv();
 			exit(EXIT_SUCCESS);
@@ -155,8 +161,8 @@ int parse_printenv_args(int argc, char *argv[])
 
 	parse_common_args(argc, argv);
 
-	while ((c = getopt_long(argc, argv, "a:c:ns:h", long_options, NULL)) !=
+	while ((c = getopt_long(argc, argv, "a:c:ns:l:h", long_options, NULL))
-	       EOF) {
+		!= EOF) {
 		switch (c) {
 		case 'n':
 			noheader = 1;
@@ -164,6 +170,7 @@ int parse_printenv_args(int argc, char *argv[])
 		case 'a':
 		case 'c':
 		case 'h':
+		case 'l':
 			/* ignore common options */
 			break;
 		default: /* '?' */
@@ -181,8 +188,8 @@ int parse_setenv_args(int argc, char *argv[])
 
 	parse_common_args(argc, argv);
 
-	while ((c = getopt_long(argc, argv, "a:c:ns:h", long_options, NULL)) !=
+	while ((c = getopt_long(argc, argv, "a:c:ns:l:h", long_options, NULL))
-	       EOF) {
+		!= EOF) {
 		switch (c) {
 		case 's':
 			script_file = optarg;
@@ -190,6 +197,7 @@ int parse_setenv_args(int argc, char *argv[])
 		case 'a':
 		case 'c':
 		case 'h':
+		case 'l':
 			/* ignore common options */
 			break;
 		default: /* '?' */
@@ -203,7 +211,7 @@ int parse_setenv_args(int argc, char *argv[])
 
 int main(int argc, char *argv[])
 {
-	const char *lockname = "/var/lock/" CMD_PRINTENV ".lock";
+	char *lockname = "/var/lock/" CMD_PRINTENV ".lock";
 	int lockfd = -1;
 	int retval = EXIT_SUCCESS;
 	char *_cmdname;
@@ -235,6 +243,18 @@ int main(int argc, char *argv[])
 	argc -= optind;
 	argv += optind;
 
+	if (env_opts.lockname) {
+		lockname = malloc(sizeof(env_opts.lockname) +
+				sizeof(CMD_PRINTENV) + 10);
+		if (!lockname) {
+			fprintf(stderr, "Unable allocate memory");
+			exit(EXIT_FAILURE);
+		}
+
+		sprintf(lockname, "%s/%s.lock",
+			env_opts.lockname, CMD_PRINTENV);
+	}
+
 	lockfd = open(lockname, O_WRONLY | O_CREAT | O_TRUNC, 0666);
 	if (-1 == lockfd) {
 		fprintf(stderr, "Error opening lock file %s\n", lockname);
@@ -260,6 +280,9 @@ int main(int argc, char *argv[])
 		}
 	}
 
+	if (env_opts.lockname)
+		free(lockname);
+
 	flock(lockfd, LOCK_UN);
 	close(lockfd);
 	return retval;