Add arbitrary config file location support

All other Osmocom projects use '-c' command line option to specify the
location of config file. Let's do the same with fallback to existing
implicit config file name logic.

Also print config file path and vty host on startup.

Change-Id: Idaac3ff8d1f8541e00c45290db948a67bb899311

2 files changed, 16 insertions, 11 deletions

diff --git a/src/host/layer23/src/mobile/app_mobile.c b/src/host/layer23/src/mobile/app_mobile.c
index 7dc7208c..fd2c94fb 100644
--- a/src/host/layer23/src/mobile/app_mobile.c
+++ b/src/host/layer23/src/mobile/app_mobile.c
@@ -409,12 +409,13 @@ int l23_app_init(int (*mncc_recv)(struct osmocom_ms *ms, int, void *),
 					" using: 'touch %s'\n", config_file);
 			return rc;
 		}
+		printf("Using configuration from %s\n", config_file);
 	}
 	vty_reading = 0;
 	rc = telnet_init_dynif(l23_ctx, NULL, vty_ip, vty_port);
 	if (rc < 0)
 		return rc;
-	printf("VTY available on port %u.\n", vty_port);
+	printf("VTY available on %s %u\n", vty_ip, vty_port);
 
 	osmo_signal_register_handler(SS_GLOBAL, &global_signal_cb, NULL);
 	osmo_signal_register_handler(SS_L1CTL, &mobile_signal_cb, NULL);
diff --git a/src/host/layer23/src/mobile/main.c b/src/host/layer23/src/mobile/main.c
index 630bc535..4a2e4ec6 100644
--- a/src/host/layer23/src/mobile/main.c
+++ b/src/host/layer23/src/mobile/main.c
@@ -38,6 +38,7 @@
 #include <getopt.h>
 #include <stdlib.h>
 #include <stdio.h>
+#include <stdbool.h>
 #include <unistd.h>
 #include <string.h>
 #include <errno.h>
@@ -51,6 +52,8 @@ struct log_target *stderr_target;
 void *l23_ctx = NULL;
 struct llist_head ms_list;
 static char *gsmtap_ip = 0;
+static const char *config_file = ".osmocom/bb/mobile.cfg";
+bool use_default_cfg = true;
 struct gsmtap_inst *gsmtap_inst = NULL;
 static char *vty_ip = "127.0.0.1";
 unsigned short vty_port = 4247;
@@ -96,6 +99,7 @@ static void print_help()
 	printf("  -d --debug		Change debug flags. default: %s\n",
 		debug_default);
 	printf("  -D --daemonize	Run as daemon\n");
+	printf("  -c --config-file filename The config file to use.\n");
 	printf("  -m --mncc-sock	Disable built-in MNCC handler and "
 		"offer socket\n");
 }
@@ -111,11 +115,12 @@ static void handle_options(int argc, char **argv)
 			{"vty-port", 1, 0, 'v'},
 			{"debug", 1, 0, 'd'},
 			{"daemonize", 0, 0, 'D'},
+			{"config-file", 1, 0, 'c'},
 			{"mncc-sock", 0, 0, 'm'},
 			{0, 0, 0, 0},
 		};
 
-		c = getopt_long(argc, argv, "hi:u:v:d:Dm",
+		c = getopt_long(argc, argv, "hi:u:c:v:d:Dm",
 				long_options, &option_index);
 		if (c == -1)
 			break;
@@ -132,6 +137,10 @@ static void handle_options(int argc, char **argv)
 		case 'u':
 			vty_ip = optarg;
 			break;
+		case 'c':
+			config_file = optarg;
+			use_default_cfg = false;
+			break;
 		case 'v':
 			vty_port = atoi(optarg);
 			break;
@@ -202,9 +211,6 @@ int main(int argc, char **argv)
 	int quit = 0;
 	int rc;
 	char const * home;
-	size_t len;
-	const char osmocomcfg[] = ".osmocom/bb/mobile.cfg";
-	char *config_file = NULL;
 
 	printf("%s\n", openbsc_copyright);
 
@@ -234,13 +240,11 @@ int main(int argc, char **argv)
 		gsmtap_source_add_sink(gsmtap_inst);
 	}
 
-	home = getenv("HOME");
-	if (home != NULL) {
-		len = strlen(home) + 1 + sizeof(osmocomcfg);
-		config_file = talloc_size(l23_ctx, len);
-		if (config_file != NULL)
-			snprintf(config_file, len, "%s/%s", home, osmocomcfg);
+	if (use_default_cfg) {
+		home = talloc_strdup(l23_ctx, getenv("HOME"));
+		config_file = talloc_asprintf_append(home, "/%s", config_file);
 	}
+
 	/* save the config file directory name */
 	config_dir = talloc_strdup(l23_ctx, config_file);
 	config_dir = dirname(config_dir);