diff options
Diffstat (limited to 'lib/stdio-write.c')
| -rw-r--r-- | lib/stdio-write.c | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/lib/stdio-write.c b/lib/stdio-write.c new file mode 100644 index 0000000..778e7cf --- /dev/null +++ b/lib/stdio-write.c @@ -0,0 +1,206 @@ +/* POSIX compatible FILE stream write function. + Copyright (C) 2008-2020 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 + +/* 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 |