doxygen + file naming

[disorder] / lib / speaker-protocol.c

diff --git a/lib/speaker-protocol.c b/lib/speaker-protocol.c
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+++ b/lib/speaker-protocol.c
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+/*
+ * This file is part of DisOrder.
+ * Copyright (C) 2005, 2007 Richard Kettlewell
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+ * USA
+ */
+/** @file lib/speaker-protocol.c
+ * @brief Speaker/server protocol support
+ */
+
+#include <config.h>
+#include "types.h"
+
+#include <sys/socket.h>
+#include <string.h>
+#include <errno.h>
+#include <sys/uio.h>
+
+#include "speaker-protocol.h"
+#include "log.h"
+
+/** @brief Send a speaker messages
+ * @param fd File descriptor to send to
+ * @param sm Pointer to message
+ * @param datafd File descriptor to pass with message or -1
+ */
+void speaker_send(int fd, const struct speaker_message *sm, int datafd) {
+  struct msghdr m;
+  struct iovec iov;
+  union {
+    struct cmsghdr cmsg;
+    char size[CMSG_SPACE(sizeof (int))];
+  } u;
+  int ret;
+
+  memset(&m, 0, sizeof m);
+  m.msg_iov = &iov;
+  m.msg_iovlen = 1;
+  iov.iov_base = (void *)sm;
+  iov.iov_len = sizeof *sm;
+  if(datafd != -1) {
+    m.msg_control = (void *)&u.cmsg;
+    m.msg_controllen = sizeof u;
+    memset(&u, 0, sizeof u);
+    u.cmsg.cmsg_len = CMSG_LEN(sizeof (int));
+    u.cmsg.cmsg_level = SOL_SOCKET;
+    u.cmsg.cmsg_type = SCM_RIGHTS;
+    *(int *)CMSG_DATA(&u.cmsg) = datafd;
+  }
+  do {
+    ret = sendmsg(fd, &m, 0);
+  } while(ret < 0 && errno == EINTR);
+  if(ret < 0)
+    fatal(errno, "sendmsg");
+}
+
+/** @brief Receive a speaker message
+ * @param fd File descriptor to read from
+ * @param sm Where to store received message
+ * @param datafd Where to store received file descriptor or NULL
+ * @return -ve on @c EAGAIN, 0 at EOF, +ve on success
+ *
+ * If @p datafd is NULL but a file descriptor is nonetheless received,
+ * the process is terminated with an error.
+ */
+int speaker_recv(int fd, struct speaker_message *sm, int *datafd) {
+  struct msghdr m;
+  struct iovec iov;
+  union {
+    struct cmsghdr cmsg;
+    char size[CMSG_SPACE(sizeof (int))];
+  } u;
+  int ret;
+
+  memset(&m, 0, sizeof m);
+  m.msg_iov = &iov;
+  m.msg_iovlen = 1;
+  iov.iov_base = (void *)sm;
+  iov.iov_len = sizeof *sm;
+  if(datafd) {
+    m.msg_control = (void *)&u.cmsg;
+    m.msg_controllen = sizeof u;
+    memset(&u, 0, sizeof u);
+    u.cmsg.cmsg_len = CMSG_LEN(sizeof (int));
+    u.cmsg.cmsg_level = SOL_SOCKET;
+    u.cmsg.cmsg_type = SCM_RIGHTS;
+    *datafd = -1;
+  }
+  do {
+    ret = recvmsg(fd, &m, MSG_DONTWAIT);
+  } while(ret < 0 && errno == EINTR);
+  if(ret < 0) {
+    if(errno != EAGAIN) fatal(errno, "recvmsg");
+    return -1;
+  }
+  if((size_t)m.msg_controllen >= CMSG_LEN(sizeof (int))) {
+    if(!datafd)
+      fatal(0, "got an unexpected file descriptor from recvmsg");
+    else
+      *datafd = *(int *)CMSG_DATA(&u.cmsg);
+  }
+  return ret;
+}
+
+/*
+Local Variables:
+c-basic-offset:2
+comment-column:40
+fill-column:79
+indent-tabs-mode:nil
+End:
+*/