| 1 | dnl @synopsis AX_FUNC_WHICH_GETHOSTBYNAME_R |
| 2 | dnl |
| 3 | dnl Determines which historical variant of the gethostbyname_r() call |
| 4 | dnl (taking three, five, or six arguments) is available on the system |
| 5 | dnl and defines one of the following macros accordingly: |
| 6 | dnl |
| 7 | dnl HAVE_FUNC_GETHOSTBYNAME_R_6 |
| 8 | dnl HAVE_FUNC_GETHOSTBYNAME_R_5 |
| 9 | dnl HAVE_FUNC_GETHOSTBYNAME_R_3 |
| 10 | dnl |
| 11 | dnl If used in conjunction with gethostname.c, the API demonstrated in |
| 12 | dnl test.c can be used regardless of which gethostbyname_r() is |
| 13 | dnl available. These example files can be found at |
| 14 | dnl http://www.csn.ul.ie/~caolan/publink/gethostbyname_r |
| 15 | dnl |
| 16 | dnl based on David Arnold's autoconf suggestion in the threads faq |
| 17 | dnl |
| 18 | dnl Originally named "AC_caolan_FUNC_WHICH_GETHOSTBYNAME_R". Rewritten |
| 19 | dnl for Autoconf 2.5x by Daniel Richard G. |
| 20 | dnl |
| 21 | dnl @category InstalledPackages |
| 22 | dnl @author Caolan McNamara <caolan@skynet.ie> |
| 23 | dnl @author Daniel Richard G. <skunk@iskunk.org> |
| 24 | dnl @version 2005-01-21 |
| 25 | dnl @license GPLWithACException |
| 26 | |
| 27 | AC_DEFUN([AX_FUNC_WHICH_GETHOSTBYNAME_R], [ |
| 28 | |
| 29 | AC_LANG_PUSH(C) |
| 30 | AC_MSG_CHECKING([how many arguments gethostbyname_r() takes]) |
| 31 | |
| 32 | AC_CACHE_VAL(ac_cv_func_which_gethostbyname_r, [ |
| 33 | |
| 34 | ################################################################ |
| 35 | |
| 36 | ac_cv_func_which_gethostbyname_r=unknown |
| 37 | |
| 38 | # |
| 39 | # ONE ARGUMENT (sanity check) |
| 40 | # |
| 41 | |
| 42 | # This should fail, as there is no variant of gethostbyname_r() that takes |
| 43 | # a single argument. If it actually compiles, then we can assume that |
| 44 | # netdb.h is not declaring the function, and the compiler is thereby |
| 45 | # assuming an implicit prototype. In which case, we're out of luck. |
| 46 | # |
| 47 | AC_COMPILE_IFELSE( |
| 48 | AC_LANG_PROGRAM( |
| 49 | [[#include <netdb.h>]], |
| 50 | [[ |
| 51 | char *name = "www.gnu.org"; |
| 52 | (void)gethostbyname_r(name) /* ; */ |
| 53 | ]]), |
| 54 | ac_cv_func_which_gethostbyname_r=no) |
| 55 | |
| 56 | # |
| 57 | # SIX ARGUMENTS |
| 58 | # (e.g. Linux) |
| 59 | # |
| 60 | |
| 61 | if test "$ac_cv_func_which_gethostbyname_r" = "unknown"; then |
| 62 | |
| 63 | AC_COMPILE_IFELSE( |
| 64 | AC_LANG_PROGRAM( |
| 65 | [[#include <netdb.h>]], |
| 66 | [[ |
| 67 | char *name = "www.gnu.org"; |
| 68 | struct hostent ret, *retp; |
| 69 | char buf@<:@1024@:>@; |
| 70 | int buflen = 1024; |
| 71 | int my_h_errno; |
| 72 | (void)gethostbyname_r(name, &ret, buf, buflen, &retp, &my_h_errno) /* ; */ |
| 73 | ]]), |
| 74 | ac_cv_func_which_gethostbyname_r=six) |
| 75 | |
| 76 | fi |
| 77 | |
| 78 | # |
| 79 | # FIVE ARGUMENTS |
| 80 | # (e.g. Solaris) |
| 81 | # |
| 82 | |
| 83 | if test "$ac_cv_func_which_gethostbyname_r" = "unknown"; then |
| 84 | |
| 85 | AC_COMPILE_IFELSE( |
| 86 | AC_LANG_PROGRAM( |
| 87 | [[#include <netdb.h>]], |
| 88 | [[ |
| 89 | char *name = "www.gnu.org"; |
| 90 | struct hostent ret; |
| 91 | char buf@<:@1024@:>@; |
| 92 | int buflen = 1024; |
| 93 | int my_h_errno; |
| 94 | (void)gethostbyname_r(name, &ret, buf, buflen, &my_h_errno) /* ; */ |
| 95 | ]]), |
| 96 | ac_cv_func_which_gethostbyname_r=five) |
| 97 | |
| 98 | fi |
| 99 | |
| 100 | # |
| 101 | # THREE ARGUMENTS |
| 102 | # (e.g. AIX, HP-UX, Tru64) |
| 103 | # |
| 104 | |
| 105 | if test "$ac_cv_func_which_gethostbyname_r" = "unknown"; then |
| 106 | |
| 107 | AC_COMPILE_IFELSE( |
| 108 | AC_LANG_PROGRAM( |
| 109 | [[#include <netdb.h>]], |
| 110 | [[ |
| 111 | char *name = "www.gnu.org"; |
| 112 | struct hostent ret; |
| 113 | struct hostent_data data; |
| 114 | (void)gethostbyname_r(name, &ret, &data) /* ; */ |
| 115 | ]]), |
| 116 | ac_cv_func_which_gethostbyname_r=three) |
| 117 | |
| 118 | fi |
| 119 | |
| 120 | ################################################################ |
| 121 | |
| 122 | ]) dnl end AC_CACHE_VAL |
| 123 | |
| 124 | case "$ac_cv_func_which_gethostbyname_r" in |
| 125 | three) |
| 126 | AC_MSG_RESULT([three]) |
| 127 | AC_DEFINE(HAVE_FUNC_GETHOSTBYNAME_R_3) |
| 128 | ;; |
| 129 | |
| 130 | five) |
| 131 | AC_MSG_RESULT([five]) |
| 132 | AC_DEFINE(HAVE_FUNC_GETHOSTBYNAME_R_5) |
| 133 | ;; |
| 134 | |
| 135 | six) |
| 136 | AC_MSG_RESULT([six]) |
| 137 | AC_DEFINE(HAVE_FUNC_GETHOSTBYNAME_R_6) |
| 138 | ;; |
| 139 | |
| 140 | no) |
| 141 | AC_MSG_RESULT([cannot find function declaration in netdb.h]) |
| 142 | ;; |
| 143 | |
| 144 | unknown) |
| 145 | AC_MSG_RESULT([can't tell]) |
| 146 | ;; |
| 147 | |
| 148 | *) |
| 149 | AC_MSG_ERROR([internal error]) |
| 150 | ;; |
| 151 | esac |
| 152 | |
| 153 | AC_LANG_POP(C) |
| 154 | |
| 155 | ]) dnl end AC_DEFUN |