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Diffstat (limited to 'm4/absolute-header.m4')
-rw-r--r-- | m4/absolute-header.m4 | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/m4/absolute-header.m4 b/m4/absolute-header.m4 new file mode 100644 index 0000000..f576d34 --- /dev/null +++ b/m4/absolute-header.m4 | |||
@@ -0,0 +1,77 @@ | |||
1 | # absolute-header.m4 serial 12 | ||
2 | dnl Copyright (C) 2006-2010 Free Software Foundation, Inc. | ||
3 | dnl This file is free software; the Free Software Foundation | ||
4 | dnl gives unlimited permission to copy and/or distribute it, | ||
5 | dnl with or without modifications, as long as this notice is preserved. | ||
6 | |||
7 | dnl From Derek Price. | ||
8 | |||
9 | # gl_ABSOLUTE_HEADER(HEADER1 HEADER2 ...) | ||
10 | # --------------------------------------- | ||
11 | # Find the absolute name of a header file, testing first if the header exists. | ||
12 | # If the header were sys/inttypes.h, this macro would define | ||
13 | # ABSOLUTE_SYS_INTTYPES_H to the `""' quoted absolute name of sys/inttypes.h | ||
14 | # in config.h | ||
15 | # (e.g. `#define ABSOLUTE_SYS_INTTYPES_H "///usr/include/sys/inttypes.h"'). | ||
16 | # The three "///" are to pacify Sun C 5.8, which otherwise would say | ||
17 | # "warning: #include of /usr/include/... may be non-portable". | ||
18 | # Use `""', not `<>', so that the /// cannot be confused with a C99 comment. | ||
19 | # Note: This macro assumes that the header file is not empty after | ||
20 | # preprocessing, i.e. it does not only define preprocessor macros but also | ||
21 | # provides some type/enum definitions or function/variable declarations. | ||
22 | AC_DEFUN([gl_ABSOLUTE_HEADER], | ||
23 | [AC_REQUIRE([AC_CANONICAL_HOST]) | ||
24 | AC_LANG_PREPROC_REQUIRE()dnl | ||
25 | m4_foreach_w([gl_HEADER_NAME], [$1], | ||
26 | [AS_VAR_PUSHDEF([gl_absolute_header], | ||
27 | [gl_cv_absolute_]m4_defn([gl_HEADER_NAME]))dnl | ||
28 | AC_CACHE_CHECK([absolute name of <]m4_defn([gl_HEADER_NAME])[>], | ||
29 | m4_defn([gl_absolute_header]), | ||
30 | [AS_VAR_PUSHDEF([ac_header_exists], | ||
31 | [ac_cv_header_]m4_defn([gl_HEADER_NAME]))dnl | ||
32 | AC_CHECK_HEADERS_ONCE(m4_defn([gl_HEADER_NAME]))dnl | ||
33 | if test AS_VAR_GET(ac_header_exists) = yes; then | ||
34 | gl_ABSOLUTE_HEADER_ONE(m4_defn([gl_HEADER_NAME])) | ||
35 | fi | ||
36 | AS_VAR_POPDEF([ac_header_exists])dnl | ||
37 | ])dnl | ||
38 | AC_DEFINE_UNQUOTED(AS_TR_CPP([ABSOLUTE_]m4_defn([gl_HEADER_NAME])), | ||
39 | ["AS_VAR_GET(gl_absolute_header)"], | ||
40 | [Define this to an absolute name of <]m4_defn([gl_HEADER_NAME])[>.]) | ||
41 | AS_VAR_POPDEF([gl_absolute_header])dnl | ||
42 | ])dnl | ||
43 | ])# gl_ABSOLUTE_HEADER | ||
44 | |||
45 | # gl_ABSOLUTE_HEADER_ONE(HEADER) | ||
46 | # ------------------------------ | ||
47 | # Like gl_ABSOLUTE_HEADER, except that: | ||
48 | # - it assumes that the header exists, | ||
49 | # - it uses the current CPPFLAGS, | ||
50 | # - it does not cache the result, | ||
51 | # - it is silent. | ||
52 | AC_DEFUN([gl_ABSOLUTE_HEADER_ONE], | ||
53 | [ | ||
54 | AC_LANG_CONFTEST([AC_LANG_SOURCE([[#include <]]m4_dquote([$1])[[>]])]) | ||
55 | dnl AIX "xlc -E" and "cc -E" omit #line directives for header files | ||
56 | dnl that contain only a #include of other header files and no | ||
57 | dnl non-comment tokens of their own. This leads to a failure to | ||
58 | dnl detect the absolute name of <dirent.h>, <signal.h>, <poll.h> | ||
59 | dnl and others. The workaround is to force preservation of comments | ||
60 | dnl through option -C. This ensures all necessary #line directives | ||
61 | dnl are present. GCC supports option -C as well. | ||
62 | case "$host_os" in | ||
63 | aix*) gl_absname_cpp="$ac_cpp -C" ;; | ||
64 | *) gl_absname_cpp="$ac_cpp" ;; | ||
65 | esac | ||
66 | dnl eval is necessary to expand gl_absname_cpp. | ||
67 | dnl Ultrix and Pyramid sh refuse to redirect output of eval, | ||
68 | dnl so use subshell. | ||
69 | AS_VAR_SET([gl_cv_absolute_]AS_TR_SH([[$1]]), | ||
70 | [`(eval "$gl_absname_cpp conftest.$ac_ext") 2>&AS_MESSAGE_LOG_FD | | ||
71 | sed -n '\#/$1#{ | ||
72 | s#.*"\(.*/$1\)".*#\1# | ||
73 | s#^/[^/]#//&# | ||
74 | p | ||
75 | q | ||
76 | }'`]) | ||
77 | ]) | ||