* add draft of source/mcast

src/sources/mcast.c

@@ -0,0 +1,162 @@
+/* Copyright 2016 Alex 'AdUser' Z (ad_user@runbox.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include "source.h"
+
+#include <sys/types.h>
+#include <fcntl.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <netdb.h>
+
+#define DEFAULT_MCAST_ADDR "239.255.186.1"
+#define DEFAULT_MCAST_PORT 3370
+
+struct _config {
+  char name[32];
+  char error[256];
+  void (*errcb)(char *errstr);
+  char addr[INET_STRADDRLEN];
+  char iface[16];
+  uint16_t port;
+  int sock;
+};
+
+static void
+errcb_stub(char *str) {
+  assert(str != NULL);
+  (void)(str);
+}
+
+cfg_t *
+create(const char *init) {
+  cfg_t *cfg = NULL;
+  assert(init != NULL);
+  if ((cfg = calloc(1, sizeof(cfg_t))) == NULL)
+    return NULL;
+  strlcpy(cfg->name, init, sizeof(cfg->name));
+  strlcpy(cfg->addr, DEFAULT_MCAST_ADDR, sizeof(cfg->addr));
+  cfg->port = DEFAULT_MCAST_PORT;
+  cfg->errcb = &errcb_stub;
+  return cfg;
+}
+
+bool
+config(cfg_t *cfg, const char *key, const char *value) {
+  assert(cfg != NULL);
+  assert(key   != NULL);
+  assert(value != NULL);
+
+  if (strcmp(key, "address") == 0) {
+    if (strncmp(value, "239.255.", 8) != 0) {
+      strlcpy(cfg->error, "mcast address should be inside 239.255.0.0/16 block");
+      return false;
+    }
+    strlcpy(cfg->addr, value, sizeof(cfg->addr));
+    return true;
+  }
+  if (strcmp(key, "port") == 0) {
+    cfg->port = atoi(value);
+    return true;
+  }
+  if (strcmp(key, "iface") == 0) {
+    strlcpy(cfg->iface, value, sizeof(cfg->iface));
+    return true;
+  }
+
+  return false;
+}
+
+bool
+ready(cfg_t *cfg) {
+  assert(cfg != NULL);
+
+  if (cfg->addr[0] != '\0')
+    return true;
+
+  return false;
+}
+
+char *
+error(cfg_t *cfg) {
+  assert(cfg != NULL);
+
+  return cfg->error;
+}
+
+void
+errcb(cfg_t *cfg, void (*cb)(char *errstr)) {
+  assert(cfg != NULL);
+  assert(cb  != NULL);
+
+  cfg->errcb = cb;
+}
+
+bool
+start(cfg_t *cfg) {
+  struct addrinfo hints;
+  struct addrinfo *result;
+  int opt;
+
+  assert(cfg != NULL);
+
+  memset(&hints, 0, sizeof(struct addrinfo));
+  hints.ai_family = AF_INET;
+  hints.ai_socktype = SOCK_DGRAM;
+  hints.ai_protocol = 0;
+
+  int ret = getaddrinfo(cfg->addr, cfg->port, &hints, &result);
+  for (struct addrinfo *rp = result; rp != NULL; rp = rp->ai_next) {
+    cfg->sock = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
+    if (cfg->sock == -1)
+      continue;
+    if ((opt = fcntl(cfg->sock, F_GETFL, 0)) < 0)
+      continue;
+    fcntl(cfg->sock, F_SETFL, opt | O_NONBLOCK);
+    opt = 1;
+    setsockopt(cfg->sock, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
+    if (connect(cfg->sock, rp->ai_addr, rp->ai_addrlen) == 0) {
+      break; /* success */
+  }
+  freeaddrinfo(result);
+
+  /* setsockopt -- socket(7) -- SO_BINDTODEVICE */
+
+  if (cfg->sock < 0) {
+    snprintf(cfg->error, sizeof(cfg->error), "can't bind to %s:%s", cfg->host, cfg->port);
+    return false;
+  }
+
+  /* TODO */
+  return true;
+}
+
+bool
+stop(cfg_t *cfg) {
+  assert(cfg != NULL);
+
+  /* TODO */
+  return true;
+}
+
+bool
+next(cfg_t *cfg, char *buf, size_t bufsize, bool reset) {
+  assert(cfg != NULL);
+  assert(buf != NULL);
+  assert(bufsize > 0);
+
+  /* TODO */
+  return false;
+}
+
+void
+destroy(cfg_t *cfg) {
+  f2b_port_t *next;
+  assert(cfg != NULL);
+
+  free(cfg);
+}