/*
 *
 * Copyright 2016, Google Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */
#include "src/core/lib/iomgr/port.h"

#ifdef GRPC_HAVE_UNIX_SOCKET

#include "src/core/lib/iomgr/sockaddr.h"

#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/un.h>

#include "src/core/lib/iomgr/unix_sockets_posix.h"

#include <grpc/support/alloc.h>
#include <grpc/support/log.h>
#include <grpc/support/useful.h>

void grpc_create_socketpair_if_unix(int sv[2]) {
  GPR_ASSERT(socketpair(AF_UNIX, SOCK_STREAM, 0, sv) == 0);
}

grpc_error *grpc_resolve_unix_domain_address(const char *name,
                                             grpc_resolved_addresses **addrs) {
  struct sockaddr_un *un;
  if (strlen(name) > GPR_ARRAY_SIZE(((struct sockaddr_un *)0)->sun_path) - 1) {
    char *err_msg;
    grpc_error *err;
    gpr_asprintf(&err_msg,
                 "Path name should not have more than %" PRIuPTR " characters.",
                 GPR_ARRAY_SIZE(un->sun_path) - 1);
    err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(err_msg);
    gpr_free(err_msg);
    return err;
  }
  *addrs = gpr_malloc(sizeof(grpc_resolved_addresses));
  (*addrs)->naddrs = 1;
  (*addrs)->addrs = gpr_malloc(sizeof(grpc_resolved_address));
  un = (struct sockaddr_un *)(*addrs)->addrs->addr;
  un->sun_family = AF_UNIX;
  strcpy(un->sun_path, name);
  (*addrs)->addrs->len = strlen(un->sun_path) + sizeof(un->sun_family) + 1;
  return GRPC_ERROR_NONE;
}

int grpc_is_unix_socket(const grpc_resolved_address *resolved_addr) {
  const struct sockaddr *addr = (const struct sockaddr *)resolved_addr->addr;
  return addr->sa_family == AF_UNIX;
}

void grpc_unlink_if_unix_domain_socket(
    const grpc_resolved_address *resolved_addr) {
  const struct sockaddr *addr = (const struct sockaddr *)resolved_addr->addr;
  if (addr->sa_family != AF_UNIX) {
    return;
  }
  struct sockaddr_un *un = (struct sockaddr_un *)resolved_addr->addr;
  struct stat st;

  if (stat(un->sun_path, &st) == 0 && (st.st_mode & S_IFMT) == S_IFSOCK) {
    unlink(un->sun_path);
  }
}

char *grpc_sockaddr_to_uri_unix_if_possible(
    const grpc_resolved_address *resolved_addr) {
  const struct sockaddr *addr = (const struct sockaddr *)resolved_addr->addr;
  if (addr->sa_family != AF_UNIX) {
    return NULL;
  }

  char *result;
  gpr_asprintf(&result, "unix:%s", ((struct sockaddr_un *)addr)->sun_path);
  return result;
}

#endif
