GNU libmicrohttpd  0.9.75
mhd_itc.h
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1 /*
2  This file is part of libmicrohttpd
3  Copyright (C) 2016 Karlson2k (Evgeny Grin)
4 
5  This library is free software; you can redistribute it and/or
6  modify it under the terms of the GNU Lesser General Public
7  License as published by the Free Software Foundation; either
8  version 2.1 of the License, or (at your option) any later version.
9 
10  This library is distributed in the hope that it will be useful,
11  but WITHOUT ANY WARRANTY; without even the implied warranty of
12  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13  Lesser General Public License for more details.
14 
15  You should have received a copy of the GNU Lesser General Public
16  License along with this library; if not, write to the Free Software
17  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18 
19 */
20 
33 #ifndef MHD_ITC_H
34 #define MHD_ITC_H 1
35 #include "mhd_itc_types.h"
36 
37 #include <fcntl.h>
38 
39 #ifndef MHD_PANIC
40 # include <stdio.h>
41 # ifdef HAVE_STDLIB_H
42 # include <stdlib.h>
43 # endif /* HAVE_STDLIB_H */
44 /* Simple implementation of MHD_PANIC, to be used outside lib */
45 # define MHD_PANIC(msg) do { fprintf (stderr, \
46  "Abnormal termination at %d line in file %s: %s\n", \
47  (int) __LINE__, __FILE__, msg); abort (); \
48 } while (0)
49 #endif /* ! MHD_PANIC */
50 
51 #if defined(_MHD_ITC_EVENTFD)
52 
53 /* **************** Optimized GNU/Linux ITC implementation by eventfd ********** */
54 #include <sys/eventfd.h>
55 #include <stdint.h> /* for uint64_t */
56 #ifdef HAVE_UNISTD_H
57 #include <unistd.h> /* for read(), write(), errno */
58 #endif /* HAVE_UNISTD_H */
59 #ifdef HAVE_STRING_H
60 #include <string.h> /* for strerror() */
61 #endif
62 
63 
69 #define MHD_itc_init_(itc) (-1 != ((itc).fd = eventfd (0, EFD_CLOEXEC \
70  | EFD_NONBLOCK)))
71 
75 #define MHD_itc_last_strerror_() strerror (errno)
76 
80 static const uint64_t _MHD_itc_wr_data = 1;
81 
88 #define MHD_itc_activate_(itc, str) \
89  ((write ((itc).fd, (const void*) &_MHD_itc_wr_data, 8) > 0) || (EAGAIN == \
90  errno))
91 
97 #define MHD_itc_r_fd_(itc) ((itc).fd)
98 
104 #define MHD_itc_w_fd_(itc) ((itc).fd)
105 
110 #define MHD_itc_clear_(itc) \
111  do { uint64_t __b; int __r; \
112  __r = read ((itc).fd, &__b, sizeof(__b)); \
113  (void) __r; } while (0)
114 
122 #define MHD_itc_destroy_(itc) ((0 == close ((itc).fd)) || (EBADF != errno))
123 
133 #define MHD_ITC_IS_VALID_(itc) (-1 != ((itc).fd))
134 
139 #define MHD_itc_set_invalid_(itc) ((itc).fd = -1)
140 
141 
142 #elif defined(_MHD_ITC_PIPE)
143 
144 /* **************** Standard UNIX ITC implementation by pipe ********** */
145 
146 #if defined(HAVE_PIPE2_FUNC) && defined(HAVE_FCNTL_H)
147 # include <fcntl.h> /* for O_CLOEXEC, O_NONBLOCK */
148 #endif /* HAVE_PIPE2_FUNC && HAVE_FCNTL_H */
149 #ifdef HAVE_UNISTD_H
150 #include <unistd.h> /* for read(), write(), errno */
151 #endif /* HAVE_UNISTD_H */
152 #ifdef HAVE_STRING_H
153 #include <string.h> /* for strerror() */
154 #endif
155 
156 
162 #ifdef HAVE_PIPE2_FUNC
163 # define MHD_itc_init_(itc) (! pipe2 ((itc).fd, O_CLOEXEC | O_NONBLOCK))
164 #else /* ! HAVE_PIPE2_FUNC */
165 # define MHD_itc_init_(itc) \
166  ( (! pipe ((itc).fd)) ? \
167  (MHD_itc_nonblocking_ ((itc)) ? \
168  (! 0) : \
169  (MHD_itc_destroy_ ((itc)), 0) ) \
170  : (0) )
171 #endif /* ! HAVE_PIPE2_FUNC */
172 
176 #define MHD_itc_last_strerror_() strerror (errno)
177 
184 #define MHD_itc_activate_(itc, str) \
185  ((write ((itc).fd[1], (const void*) (str), 1) > 0) || (EAGAIN == errno))
186 
187 
193 #define MHD_itc_r_fd_(itc) ((itc).fd[0])
194 
200 #define MHD_itc_w_fd_(itc) ((itc).fd[1])
201 
206 #define MHD_itc_clear_(itc) do \
207  { long __b; \
208  while (0 < read ((itc).fd[0], &__b, sizeof(__b))) \
209  {} } while (0)
210 
216 #define MHD_itc_destroy_(itc) \
217  ( (0 == close ((itc).fd[0])) ? \
218  (0 == close ((itc).fd[1])) : \
219  ((close ((itc).fd[1])), 0) )
220 
230 #define MHD_ITC_IS_VALID_(itc) (-1 != (itc).fd[0])
231 
236 #define MHD_itc_set_invalid_(itc) ((itc).fd[0] = (itc).fd[1] = -1)
237 
238 #ifndef HAVE_PIPE2_FUNC
245 int
246 MHD_itc_nonblocking_ (struct MHD_itc_ itc);
247 
248 #endif /* ! HAVE_PIPE2_FUNC */
249 
250 
251 #elif defined(_MHD_ITC_SOCKETPAIR)
252 
253 /* **************** ITC implementation by socket pair ********** */
254 
255 #include "mhd_sockets.h"
256 
257 
263 #ifdef MHD_socket_pair_nblk_
264 # define MHD_itc_init_(itc) MHD_socket_pair_nblk_ ((itc).sk)
265 #else /* ! MHD_socket_pair_nblk_ */
266 # define MHD_itc_init_(itc) \
267  (MHD_socket_pair_ ((itc).sk) ? \
268  (MHD_itc_nonblocking_ ((itc)) ? \
269  (! 0) : \
270  (MHD_itc_destroy_ ((itc)), 0) ) \
271  : (0))
272 #endif /* ! MHD_socket_pair_nblk_ */
273 
277 #define MHD_itc_last_strerror_() MHD_socket_last_strerr_ ()
278 
285 #define MHD_itc_activate_(itc, str) \
286  ((MHD_send_ ((itc).sk[1], (str), 1) > 0) || \
287  (MHD_SCKT_ERR_IS_EAGAIN_ (MHD_socket_get_error_ ())))
288 
294 #define MHD_itc_r_fd_(itc) ((itc).sk[0])
295 
301 #define MHD_itc_w_fd_(itc) ((itc).sk[1])
302 
307 #define MHD_itc_clear_(itc) do \
308  { long __b; \
309  while (0 < recv ((itc).sk[0], \
310  (char*) &__b, \
311  sizeof(__b), 0)) \
312  {} } while (0)
313 
319 #define MHD_itc_destroy_(itc) \
320  (MHD_socket_close_ ((itc).sk[0]) ? \
321  MHD_socket_close_ ((itc).sk[1]) : \
322  ((void) MHD_socket_close_ ((itc).sk[1]), 0) )
323 
324 
334 #define MHD_ITC_IS_VALID_(itc) (MHD_INVALID_SOCKET != (itc).sk[0])
335 
340 #define MHD_itc_set_invalid_(itc) ((itc).sk[0] = (itc).sk[1] = \
341  MHD_INVALID_SOCKET)
342 
343 #ifndef MHD_socket_pair_nblk_
344 # define MHD_itc_nonblocking_(pip) (MHD_socket_nonblocking_ ((pip).sk[0]) && \
345  MHD_socket_nonblocking_ ((pip).sk[1]))
346 #endif /* ! MHD_socket_pair_nblk_ */
347 
348 #endif /* _MHD_ITC_SOCKETPAIR */
349 
355 #define MHD_itc_destroy_chk_(itc) do { \
356  if (! MHD_itc_destroy_ (itc)) \
357  MHD_PANIC (_ ("Failed to destroy ITC.\n")); \
358 } while (0)
359 
369 #define MHD_ITC_IS_INVALID_(itc) (! MHD_ITC_IS_VALID_ (itc))
370 
371 #endif /* MHD_ITC_H */
Types for platform-independent inter-thread communication.