lib/tsocket/tsocket_helpers.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Copyright (C) Stefan Metzmacher 2009
   5
   6      ** NOTE! The following LGPL license applies to the tevent
   7      ** library. This does NOT imply that all of Samba is released
   8      ** under the LGPL
   9
  10    This library is free software; you can redistribute it and/or
  11    modify it under the terms of the GNU Lesser General Public
  12    License as published by the Free Software Foundation; either
  13    version 3 of the License, or (at your option) any later version.
  14
  15    This library is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18    Lesser General Public License for more details.
  19
  20    You should have received a copy of the GNU Lesser General Public
  21    License along with this library; if not, see <http://www.gnu.org/licenses/>.
  22 */
  23
  24 #include "replace.h"
  25 #include "system/network.h"
  26 #include "system/filesys.h"
  27 #include "tsocket.h"
  28 #include "tsocket_internal.h"
  29
  30 int tsocket_error_from_errno(int ret,
  31                              int sys_errno,
  32                              bool *retry)
  33 {
  34         *retry = false;
  35
  36         if (ret >= 0) {
  37                 return 0;
  38         }
  39
  40         if (ret != -1) {
  41                 return EIO;
  42         }
  43
  44         if (sys_errno == 0) {
  45                 return EIO;
  46         }
  47
  48         if (sys_errno == EINTR) {
  49                 *retry = true;
  50                 return sys_errno;
  51         }
  52
  53         if (sys_errno == EINPROGRESS) {
  54                 *retry = true;
  55                 return sys_errno;
  56         }
  57
  58         if (sys_errno == EAGAIN) {
  59                 *retry = true;
  60                 return sys_errno;
  61         }
  62
  63 #ifdef EWOULDBLOCK
  64         if (sys_errno == EWOULDBLOCK) {
  65                 *retry = true;
  66                 return sys_errno;
  67         }
  68 #endif
  69
  70         return sys_errno;
  71 }
  72
  73 int tsocket_simple_int_recv(struct tevent_req *req, int *perrno)
  74 {
  75         enum tevent_req_state state;
  76         uint64_t error;
  77
  78         if (!tevent_req_is_error(req, &state, &error)) {
  79                 return 0;
  80         }
  81
  82         switch (state) {
  83         case TEVENT_REQ_NO_MEMORY:
  84                 *perrno = ENOMEM;
  85                 return -1;
  86         case TEVENT_REQ_TIMED_OUT:
  87                 *perrno = ETIMEDOUT;
  88                 return -1;
  89         case TEVENT_REQ_USER_ERROR:
  90                 *perrno = (int)error;
  91                 return -1;
  92         default:
  93                 *perrno = EIO;
  94                 return -1;
  95         }
  96
  97         *perrno = EIO;
  98         return -1;
  99 }
 100
 101 int tsocket_common_prepare_fd(int fd, bool high_fd)
 102 {
 103         int i;
 104         int sys_errno = 0;
 105         int fds[3];
 106         int num_fds = 0;
 107
 108         int result, flags;
 109
 110         if (fd == -1) {
 111                 return -1;
 112         }
 113
 114         /* first make a fd >= 3 */
 115         if (high_fd) {
 116                 while (fd < 3) {
 117                         fds[num_fds++] = fd;
 118                         fd = dup(fd);
 119                         if (fd == -1) {
 120                                 sys_errno = errno;
 121                                 break;
 122                         }
 123                 }
 124                 for (i=0; i<num_fds; i++) {
 125                         close(fds[i]);
 126                 }
 127                 if (fd == -1) {
 128                         errno = sys_errno;
 129                         return fd;
 130                 }
 131         }
 132
 133         /* fd should be nonblocking. */
 134
 135 #ifdef O_NONBLOCK
 136 #define FLAG_TO_SET O_NONBLOCK
 137 #else
 138 #ifdef SYSV
 139 #define FLAG_TO_SET O_NDELAY
 140 #else /* BSD */
 141 #define FLAG_TO_SET FNDELAY
 142 #endif
 143 #endif
 144
 145         if ((flags = fcntl(fd, F_GETFL)) == -1) {
 146                 goto fail;
 147         }
 148
 149         flags |= FLAG_TO_SET;
 150         if (fcntl(fd, F_SETFL, flags) == -1) {
 151                 goto fail;
 152         }
 153
 154 #undef FLAG_TO_SET
 155
 156         /* fd should be closed on exec() */
 157 #ifdef FD_CLOEXEC
 158         result = flags = fcntl(fd, F_GETFD, 0);
 159         if (flags >= 0) {
 160                 flags |= FD_CLOEXEC;
 161                 result = fcntl(fd, F_SETFD, flags);
 162         }
 163         if (result < 0) {
 164                 goto fail;
 165         }
 166 #endif
 167         return fd;
 168
 169  fail:
 170         if (fd != -1) {
 171                 sys_errno = errno;
 172                 close(fd);
 173                 errno = sys_errno;
 174         }
 175         return -1;
 176 }
 177