summaryrefslogtreecommitdiffstats
path: root/gl/lib/stdio-write.c
blob: 3fbd27229ca6599f81ef95648be268f76dd4539b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
/* POSIX compatible FILE stream write function.
   Copyright (C) 2008-2019 Free Software Foundation, Inc.
   Written by Bruno Haible <bruno@clisp.org>, 2008.

   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 3 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, see <https://www.gnu.org/licenses/>.  */

#include <config.h>

/* Specification.  */
#include <stdio.h>

/* Replace these functions only if module 'nonblocking' or module 'sigpipe' is
   requested.  */
#if GNULIB_NONBLOCKING || GNULIB_SIGPIPE

/* On native Windows platforms, SIGPIPE does not exist.  When write() is
   called on a pipe with no readers, WriteFile() fails with error
   GetLastError() = ERROR_NO_DATA, and write() in consequence fails with
   error EINVAL.  This write() function is at the basis of the function
   which flushes the buffer of a FILE stream.  */

# if defined _WIN32 && ! defined __CYGWIN__

#  include <errno.h>
#  include <signal.h>
#  include <io.h>

#  define WIN32_LEAN_AND_MEAN  /* avoid including junk */
#  include <windows.h>

#  if GNULIB_MSVC_NOTHROW
#   include "msvc-nothrow.h"
#  else
#   include <io.h>
#  endif

#  if GNULIB_NONBLOCKING
#   define CLEAR_ERRNO \
      errno = 0;
#   define HANDLE_ENOSPC \
          if (errno == ENOSPC && ferror (stream))                             \
            {                                                                 \
              int fd = fileno (stream);                                       \
              if (fd >= 0)                                                    \
                {                                                             \
                  HANDLE h = (HANDLE) _get_osfhandle (fd);                    \
                  if (GetFileType (h) == FILE_TYPE_PIPE)                      \
                    {                                                         \
                      /* h is a pipe or socket.  */                           \
                      DWORD state;                                            \
                      if (GetNamedPipeHandleState (h, &state, NULL, NULL,     \
                                                   NULL, NULL, 0)             \
                          && (state & PIPE_NOWAIT) != 0)                      \
                        /* h is a pipe in non-blocking mode.                  \
                           Change errno from ENOSPC to EAGAIN.  */            \
                        errno = EAGAIN;                                       \
                    }                                                         \
                }                                                             \
            }                                                                 \
          else
#  else
#   define CLEAR_ERRNO
#   define HANDLE_ENOSPC
#  endif

#  if GNULIB_SIGPIPE
#   define CLEAR_LastError \
      SetLastError (0);
#   define HANDLE_ERROR_NO_DATA \
          if (GetLastError () == ERROR_NO_DATA && ferror (stream))            \
            {                                                                 \
              int fd = fileno (stream);                                       \
              if (fd >= 0                                                     \
                  && GetFileType ((HANDLE) _get_osfhandle (fd))               \
                     == FILE_TYPE_PIPE)                                       \
                {                                                             \
                  /* Try to raise signal SIGPIPE.  */                         \
                  raise (SIGPIPE);                                            \
                  /* If it is currently blocked or ignored, change errno from \
                     EINVAL to EPIPE.  */                                     \
                  errno = EPIPE;                                              \
                }                                                             \
            }                                                                 \
          else
#  else
#   define CLEAR_LastError
#   define HANDLE_ERROR_NO_DATA
#  endif

#  define CALL_WITH_SIGPIPE_EMULATION(RETTYPE, EXPRESSION, FAILED) \
  if (ferror (stream))                                                        \
    return (EXPRESSION);                                                      \
  else                                                                        \
    {                                                                         \
      RETTYPE ret;                                                            \
      CLEAR_ERRNO                                                             \
      CLEAR_LastError                                                         \
      ret = (EXPRESSION);                                                     \
      if (FAILED)                                                             \
        {                                                                     \
          HANDLE_ENOSPC                                                       \
          HANDLE_ERROR_NO_DATA                                                \
          ;                                                                   \
        }                                                                     \
      return ret;                                                             \
    }

#  if !REPLACE_PRINTF_POSIX /* avoid collision with printf.c */
int
printf (const char *format, ...)
{
  int retval;
  va_list args;

  va_start (args, format);
  retval = vfprintf (stdout, format, args);
  va_end (args);

  return retval;
}
#  endif

#  if !REPLACE_FPRINTF_POSIX /* avoid collision with fprintf.c */
int
fprintf (FILE *stream, const char *format, ...)
{
  int retval;
  va_list args;

  va_start (args, format);
  retval = vfprintf (stream, format, args);
  va_end (args);

  return retval;
}
#  endif

#  if !REPLACE_VPRINTF_POSIX /* avoid collision with vprintf.c */
int
vprintf (const char *format, va_list args)
{
  return vfprintf (stdout, format, args);
}
#  endif

#  if !REPLACE_VFPRINTF_POSIX /* avoid collision with vfprintf.c */
int
vfprintf (FILE *stream, const char *format, va_list args)
#undef vfprintf
{
  CALL_WITH_SIGPIPE_EMULATION (int, vfprintf (stream, format, args), ret == EOF)
}
#  endif

int
putchar (int c)
{
  return fputc (c, stdout);
}

int
fputc (int c, FILE *stream)
#undef fputc
{
  CALL_WITH_SIGPIPE_EMULATION (int, fputc (c, stream), ret == EOF)
}

int
fputs (const char *string, FILE *stream)
#undef fputs
{
  CALL_WITH_SIGPIPE_EMULATION (int, fputs (string, stream), ret == EOF)
}

int
puts (const char *string)
#undef puts
{
  FILE *stream = stdout;
  CALL_WITH_SIGPIPE_EMULATION (int, puts (string), ret == EOF)
}

size_t
fwrite (const void *ptr, size_t s, size_t n, FILE *stream)
#undef fwrite
{
  CALL_WITH_SIGPIPE_EMULATION (size_t, fwrite (ptr, s, n, stream), ret < n)
}

# endif
#endif