summaryrefslogtreecommitdiffstats
path: root/gl/m4/fpurge.m4
diff options
context:
space:
mode:
Diffstat (limited to 'gl/m4/fpurge.m4')
-rw-r--r--gl/m4/fpurge.m473
1 files changed, 73 insertions, 0 deletions
diff --git a/gl/m4/fpurge.m4 b/gl/m4/fpurge.m4
new file mode 100644
index 0000000..b365409
--- /dev/null
+++ b/gl/m4/fpurge.m4
@@ -0,0 +1,73 @@
1# fpurge.m4 serial 12
2dnl Copyright (C) 2007, 2009-2023 Free Software Foundation, Inc.
3dnl This file is free software; the Free Software Foundation
4dnl gives unlimited permission to copy and/or distribute it,
5dnl with or without modifications, as long as this notice is preserved.
6
7AC_DEFUN([gl_FUNC_FPURGE],
8[
9 AC_REQUIRE([gl_STDIO_H_DEFAULTS])
10 AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
11 AC_CHECK_HEADERS_ONCE([stdio_ext.h])
12 AC_CHECK_FUNCS_ONCE([fpurge])
13 AC_CHECK_FUNCS_ONCE([__fpurge])
14 AC_CHECK_DECLS([fpurge], , , [[#include <stdio.h>]])
15 if test "x$ac_cv_func_fpurge" = xyes; then
16 HAVE_FPURGE=1
17 # Detect BSD bug. Only cygwin 1.7 and musl are known to be immune.
18 AC_CACHE_CHECK([whether fpurge works], [gl_cv_func_fpurge_works],
19 [AC_RUN_IFELSE(
20 [AC_LANG_PROGRAM(
21 [[#include <stdio.h>
22]],
23 [[FILE *f = fopen ("conftest.txt", "w+");
24 if (!f)
25 return 1;
26 if (fputc ('a', f) != 'a')
27 { fclose (f); return 2; }
28 rewind (f);
29 if (fgetc (f) != 'a')
30 { fclose (f); return 3; }
31 if (fgetc (f) != EOF)
32 { fclose (f); return 4; }
33 if (fpurge (f) != 0)
34 { fclose (f); return 5; }
35 if (putc ('b', f) != 'b')
36 { fclose (f); return 6; }
37 if (fclose (f) != 0)
38 return 7;
39 if ((f = fopen ("conftest.txt", "r")) == NULL)
40 return 8;
41 if (fgetc (f) != 'a')
42 { fclose (f); return 9; }
43 if (fgetc (f) != 'b')
44 { fclose (f); return 10; }
45 if (fgetc (f) != EOF)
46 { fclose (f); return 11; }
47 if (fclose (f) != 0)
48 return 12;
49 if (remove ("conftest.txt") != 0)
50 return 13;
51 return 0;
52 ]])],
53 [gl_cv_func_fpurge_works=yes],
54 [gl_cv_func_fpurge_works=no],
55 [case "$host_os" in
56 # Guess yes on musl systems.
57 *-musl*) gl_cv_func_fpurge_works="guessing yes" ;;
58 # Otherwise obey --enable-cross-guesses.
59 *) gl_cv_func_fpurge_works="$gl_cross_guess_normal" ;;
60 esac
61 ])
62 ])
63 case "$gl_cv_func_fpurge_works" in
64 *yes) ;;
65 *) REPLACE_FPURGE=1 ;;
66 esac
67 else
68 HAVE_FPURGE=0
69 fi
70 if test "x$ac_cv_have_decl_fpurge" = xno; then
71 HAVE_DECL_FPURGE=0
72 fi
73])