diff options
Diffstat (limited to 'gnulib/m4/fflush.m4')
m--------- | gnulib | 0 | ||||
-rw-r--r-- | gnulib/m4/fflush.m4 | 82 |
2 files changed, 82 insertions, 0 deletions
diff --git a/gnulib b/gnulib deleted file mode 160000 -Subproject 4fc10daa05477586fea99b6b3ca02a87d1102fa diff --git a/gnulib/m4/fflush.m4 b/gnulib/m4/fflush.m4 new file mode 100644 index 00000000..56c0aedc --- /dev/null +++ b/gnulib/m4/fflush.m4 @@ -0,0 +1,82 @@ +# fflush.m4 serial 7 + +# Copyright (C) 2007-2010 Free Software Foundation, Inc. +# This file is free software; the Free Software Foundation +# gives unlimited permission to copy and/or distribute it, +# with or without modifications, as long as this notice is preserved. + +dnl From Eric Blake + +dnl Find out how to obey POSIX semantics of fflush(stdin) discarding +dnl unread input on seekable streams, rather than C99 undefined semantics. + +AC_DEFUN([gl_FUNC_FFLUSH], +[ + AC_CACHE_CHECK([whether fflush works on input streams], + [gl_cv_func_fflush_stdin], + [echo hello world > conftest.txt + AC_RUN_IFELSE([AC_LANG_PROGRAM( + [[ +#include <stdio.h> +#include <unistd.h> + ]], [[FILE *f = fopen ("conftest.txt", "r"); + char buffer[10]; + int fd; + int c; + if (f == NULL) + return 1; + fd = fileno (f); + if (fd < 0 || fread (buffer, 1, 5, f) != 5) + return 2; + /* For deterministic results, ensure f read a bigger buffer. */ + if (lseek (fd, 0, SEEK_CUR) == 5) + return 3; + /* POSIX requires fflush-fseek to set file offset of fd. This fails + on BSD systems and on mingw. */ + if (fflush (f) != 0 || fseek (f, 0, SEEK_CUR) != 0) + return 4; + if (lseek (fd, 0, SEEK_CUR) != 5) + return 5; + /* Verify behaviour of fflush after ungetc. See + <http://www.opengroup.org/austin/aardvark/latest/xshbug3.txt> */ + /* Verify behaviour of fflush after a backup ungetc. This fails on + mingw. */ + c = fgetc (f); + ungetc (c, f); + fflush (f); + if (fgetc (f) != c) + return 6; + /* Verify behaviour of fflush after a non-backup ungetc. This fails + on glibc 2.8 and on BSD systems. */ + c = fgetc (f); + ungetc ('@', f); + fflush (f); + if (fgetc (f) != c) + return 7; + return 0; + ]])], [gl_cv_func_fflush_stdin=yes], [gl_cv_func_fflush_stdin=no], + [dnl Pessimistically assume fflush is broken. + gl_cv_func_fflush_stdin=no]) + rm conftest.txt + ]) + if test $gl_cv_func_fflush_stdin = no; then + gl_REPLACE_FFLUSH + fi +]) + +AC_DEFUN([gl_REPLACE_FFLUSH], +[ + AC_LIBOBJ([fflush]) + AC_LIBOBJ([fseeko]) + AC_REQUIRE([gl_STDIO_H_DEFAULTS]) + REPLACE_FFLUSH=1 + REPLACE_FSEEKO=1 + gl_PREREQ_FFLUSH +]) + +# Prerequisites of lib/fflush.c. +AC_DEFUN([gl_PREREQ_FFLUSH], +[ + AC_REQUIRE([AC_C_INLINE]) + : +]) |