Make the config file overridable

diff --git a/mqtt-arp.c b/mqtt-arp.c
index bc65fbb2acf63088be69342005ba892bc72fc09e..024f44ccee9284f560a79f8794000f500fc37f26 100644 (file)
--- a/mqtt-arp.c
+++ b/mqtt-arp.c
@@ -293,8 +293,10 @@ int read_config(char *file, struct ma_config *config, int *macs)
        int i;
 
        f = fopen(file, "r");
-       if (f == NULL)
+       if (f == NULL) {
+               fprintf(stderr, "Could not read config file %s\n", file);
                return errno;
+       }
 
 #define INT_OPTION(opt, var) \
        if (strncmp(line, opt " ", sizeof(opt)) == 0) { \
@@ -341,6 +343,67 @@ int read_config(char *file, struct ma_config *config, int *macs)
        return 0;
 }
 
+void override_config(const struct ma_config *source, struct ma_config *target)
+{
+       int i;
+
+       if (source->mqtt_host != NULL) {
+               target->mqtt_host = source->mqtt_host;
+       }
+       if (source->mqtt_port != 0) {
+               target->mqtt_port = source->mqtt_port;
+       }
+       if (source->mqtt_username != NULL) {
+               target->mqtt_username = source->mqtt_username;
+       }
+       if (source->mqtt_password != NULL) {
+               target->mqtt_password = source->mqtt_password;
+       }
+       if (source->mqtt_topic != NULL) {
+               target->mqtt_topic = source->mqtt_topic;
+       }
+       if (source->location != NULL) {
+               target->location = source->location;
+       }
+       if (source->capath != NULL) {
+               target->capath = source->capath;
+       }
+       for (i = 0; i < MAX_MACS; ++i) {
+               if (source->macs[i].valid) {
+                       memcpy(&target->macs[i], &source->macs[i], sizeof(struct mac_entry));
+               }
+       }
+}
+
+void print_config(const struct ma_config *config)
+{
+       int i, j;
+
+       printf("Config:\n");
+       printf("mqtt_host: %s\n", config->mqtt_host ? config->mqtt_host : "NULL");
+       printf("mqtt_port: %d\n", config->mqtt_port);
+       printf("mqtt_username: %s\n", config->mqtt_username ? config->mqtt_username : "NULL");
+       printf("mqtt_password: %s\n", config->mqtt_password ? config->mqtt_password : "NULL");
+       printf("mqtt_topic: %s\n", config->mqtt_topic ? config->mqtt_topic : "NULL");
+       printf("location: %s\n", config->location ? config->location : "NULL");
+       printf("capath: %s\n", config->capath ? config->capath : "NULL");
+
+       for (i = 0; i < MAX_MACS; ++i) {
+               if (config->macs[i].valid) {
+                       printf("macs[%d]: { valid: true, mac: ", i);
+                       for (j = 0; j < 6; ++j) {
+                               printf("%02x", config->macs[i].mac[j]);
+                               if (j < 5) {
+                                       printf(":");
+                               }
+                       }
+                       printf("\n");
+               } else {
+                       printf("macs[%d]: { valid: false }\n", i);
+               }
+       }
+}
+
 struct option long_options[] = {
        { "capath", required_argument, 0, 'c' },
        { "host", required_argument, 0, 'h' },
@@ -351,6 +414,7 @@ struct option long_options[] = {
        { "topic", required_argument, 0, 't' },
        { "username", required_argument, 0, 'u' },
        { "verbose", no_argument, 0, 'v' },
+       { "configfile", required_argument, 0, 'f' },
        { 0, 0, 0, 0 }
 };
 
@@ -359,32 +423,34 @@ int main(int argc, char *argv[])
        int sock;
        struct mosquitto *mosq;
        struct ma_config config;
+       struct ma_config cmdline_config;
        int option_index = 0;
        int macs = 0;
        int c;
+       char *config_file = CONFIG_FILE;
 
        bzero(&config, sizeof(config));
+       bzero(&cmdline_config, sizeof(cmdline_config));
        config.mqtt_port = MQTT_PORT;
 
-       /* Read config before parsing command line */
-       read_config(CONFIG_FILE, &config, &macs);
-
        while (1) {
-               c = getopt_long(argc, argv, "c:h:l:m:p:P:t:u:v",
+               c = getopt_long(argc, argv, "c:h:l:m:p:P:t:u:f:v",
                                long_options, &option_index);
 
                if (c == -1)
                        break;
-
                switch (c) {
+               case 'f':
+                       config_file = optarg;
+                       break;
                case 'c':
-                       config.capath = optarg;
+                       cmdline_config.capath = optarg;
                        break;
                case 'h':
-                       config.mqtt_host = optarg;
+                       cmdline_config.mqtt_host = optarg;
                        break;
                case 'l':
-                       config.location = optarg;
+                       cmdline_config.location = optarg;
                        break;
                case 'm':
                        if (macs >= MAX_MACS) {
@@ -394,26 +460,26 @@ int main(int argc, char *argv[])
                        }
                        sscanf(optarg,
                                "%02hhx:%02hhx:%02hhx:%02hhx:%02hhx:%02hhx",
-                               &config.macs[macs].mac[0],
-                               &config.macs[macs].mac[1],
-                               &config.macs[macs].mac[2],
-                               &config.macs[macs].mac[3],
-                               &config.macs[macs].mac[4],
-                               &config.macs[macs].mac[5]);
-                       config.macs[macs].valid = true;
+                               &cmdline_config.macs[macs].mac[0],
+                               &cmdline_config.macs[macs].mac[1],
+                               &cmdline_config.macs[macs].mac[2],
+                               &cmdline_config.macs[macs].mac[3],
+                               &cmdline_config.macs[macs].mac[4],
+                               &cmdline_config.macs[macs].mac[5]);
+                       cmdline_config.macs[macs].valid = true;
                        macs++;
                        break;
                case 'p':
-                       config.mqtt_port = atoi(optarg);
+                       cmdline_config.mqtt_port = atoi(optarg);
                        break;
                case 'P':
-                       config.mqtt_password = optarg;
+                       cmdline_config.mqtt_password = optarg;
                        break;
                case 't':
-                       config.mqtt_topic = optarg;
+                       cmdline_config.mqtt_topic = optarg;
                        break;
                case 'u':
-                       config.mqtt_username = optarg;
+                       cmdline_config.mqtt_username = optarg;
                        break;
                case 'v':
                        debug = true;
@@ -424,6 +490,10 @@ int main(int argc, char *argv[])
                }
        }
 
+       read_config(config_file, &config, &macs);
+
+       override_config(&cmdline_config, &config);
+
        if (!config.mqtt_host)
                config.mqtt_host = MQTT_HOST;
        if (!config.mqtt_topic)
@@ -431,6 +501,9 @@ int main(int argc, char *argv[])
        if (!config.location)
                config.location = LOCATION;
 
+       if (debug)
+               print_config(&config);
+
        signal(SIGTERM, shutdown_request);
 
        sock = netlink_init();