1 files changed, 82 insertions, 0 deletions

diff --git a/mfi-mqtt/mosquitto.c b/mfi-mqtt/mosquitto.c
new file mode 100644
index 0000000..1f1a64e
--- /dev/null
+++ b/mfi-mqtt/mosquitto.c
@@ -0,0 +1,82 @@
+#include <stdio.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "mosquitto.h"
+
+int client_id_generate(char **output)
+{
+    int len;
+        char hostname[256];
+
+    *output = calloc(sizeof(char), MOSQ_MQTT_ID_MAX_LENGTH);
+    if (!*output) {
+        fprintf(stderr, "Error: Out of memory. %s\n", strerror(errno));
+        mosquitto_lib_cleanup();
+        return 1;
+    }
+
+    memset(hostname, 0, sizeof(hostname));
+    gethostname(hostname, 255);
+
+    /* Clamp length to MQTT maximum client ID length */
+    len = strlen("mfi|-") + 6 + strlen(hostname);
+    if (len > MOSQ_MQTT_ID_MAX_LENGTH - 1) {
+        len = MOSQ_MQTT_ID_MAX_LENGTH - 1;
+    }
+
+    snprintf(*output, len, "mfi|%d-%s", getpid(), hostname);
+
+        return MOSQ_ERR_SUCCESS;
+}
+
+struct mosquitto * connect_to_broker(char *host, int port) {
+    int rc;
+    char *id;
+    struct mosquitto *mosq;
+
+        mosquitto_lib_init();
+
+    if (client_id_generate(&id)) {
+        return NULL;
+    }
+
+        mosq = mosquitto_new(id, true, NULL);
+        if (!mosq) {
+                switch (errno) {
+                        case ENOMEM:
+                                fprintf(stderr, "Error: Out of memory.\n");
+                                break;
+                        case EINVAL:
+                                fprintf(stderr, "Error: Invalid id and/or clean_session.\n");
+                                break;
+                }
+                mosquitto_lib_cleanup();
+                return NULL;
+        }
+
+    int protocol_version = MQTT_PROTOCOL_V311;
+
+        mosquitto_max_inflight_messages_set(mosq, 20);
+        mosquitto_opts_set(mosq, MOSQ_OPT_PROTOCOL_VERSION, &protocol_version);
+
+        rc = mosquitto_connect(mosq, host, port, 60);
+        if (rc > 0) {
+        if (rc == MOSQ_ERR_ERRNO) {
+            fprintf(stderr, "Error: %s\n", strerror(errno));
+        } else {
+            fprintf(stderr, "Unable to connect (%s).\n", mosquitto_strerror(rc));
+        }
+                mosquitto_lib_cleanup();
+                return NULL;
+        }
+
+    return mosq;
+}
+
+void shutdown_broker(struct mosquitto *mosq) {
+    mosquitto_destroy(mosq);
+    mosquitto_lib_cleanup();
+}