rm_/lib/stdio-write.c
2022-07-28 14:16:50 +08:00

207 lines
7.4 KiB
C

/* POSIX compatible FILE stream write function.
Copyright (C) 2008-2022 Free Software Foundation, Inc.
Written by Bruno Haible <bruno@clisp.org>, 2008.
This file is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation; either version 2.1 of the
License, or (at your option) any later version.
This file 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 Lesser General Public License for more details.
You should have received a copy of the GNU Lesser 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
/* Don't assume that UNICODE is not defined. */
# undef GetNamedPipeHandleState
# define GetNamedPipeHandleState GetNamedPipeHandleStateA
# 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