1dnl Helper functions to manage compiler variables. 2dnl $Id: lib-helper.m4 10306 2018-12-02 14:26:13Z iulius $ 3dnl 4dnl These are a wide variety of helper macros to make it easier to construct 5dnl standard macros to probe for a library and to set library-specific 6dnl CPPFLAGS, LDFLAGS, and LIBS shell substitution variables. Most of them 7dnl take as one of the arguments the prefix string to use for variables, which 8dnl is usually something like "KRB5" or "GSSAPI". 9dnl 10dnl Depends on INN_SET_LDFLAGS. 11dnl 12dnl The canonical version of this file is maintained in the rra-c-util 13dnl package, available at <https://www.eyrie.org/~eagle/software/rra-c-util/>. 14dnl 15dnl Written by Russ Allbery <eagle@eyrie.org> 16dnl Copyright 2018 Russ Allbery <eagle@eyrie.org> 17dnl Copyright 2011, 2013 18dnl The Board of Trustees of the Leland Stanford Junior University 19dnl 20dnl This file is free software; the authors give unlimited permission to copy 21dnl and/or distribute it, with or without modifications, as long as this 22dnl notice is preserved. 23dnl 24dnl SPDX-License-Identifier: FSFULLR 25 26dnl Add the library flags to the default compiler flags and then remove them. 27dnl 28dnl To use these macros, pass the prefix string used for the variables as the 29dnl only argument. For example, to use these for a library with KRB5 as a 30dnl prefix, one would use: 31dnl 32dnl AC_DEFUN([INN_LIB_KRB5_SWITCH], [INN_LIB_HELPER_SWITCH([KRB5])]) 33dnl AC_DEFUN([INN_LIB_KRB5_RESTORE], [INN_LIB_HELPER_RESTORE([KRB5])]) 34dnl 35dnl Then, wrap checks for library features with INN_LIB_KRB5_SWITCH and 36dnl INN_LIB_KRB5_RESTORE. 37AC_DEFUN([INN_LIB_HELPER_SWITCH], 38[inn_$1[]_save_CPPFLAGS="$CPPFLAGS" 39 inn_$1[]_save_LDFLAGS="$LDFLAGS" 40 inn_$1[]_save_LIBS="$LIBS" 41 CPPFLAGS="$$1[]_CPPFLAGS $CPPFLAGS" 42 LDFLAGS="$$1[]_LDFLAGS $LDFLAGS" 43 LIBS="$$1[]_LIBS $LIBS"]) 44 45AC_DEFUN([INN_LIB_HELPER_RESTORE], 46[CPPFLAGS="$inn_$1[]_save_CPPFLAGS" 47 LDFLAGS="$inn_$1[]_save_LDFLAGS" 48 LIBS="$inn_$1[]_save_LIBS"]) 49 50dnl Given _root, _libdir, and _includedir variables set for a library (set by 51dnl INN_LIB_HELPER_WITH*), set the LDFLAGS and CPPFLAGS variables for that 52dnl library accordingly. Takes the variable prefix as the only argument. 53AC_DEFUN([INN_LIB_HELPER_PATHS], 54[AS_IF([test x"$inn_$1[]_libdir" != x], 55 [$1[]_LDFLAGS="-L$inn_$1[]_libdir"], 56 [AS_IF([test x"$inn_$1[]_root" != x], 57 [INN_SET_LDFLAGS([$1][_LDFLAGS], [${inn_$1[]_root}])])]) 58 AS_IF([test x"$inn_$1[]_includedir" != x], 59 [$1[]_CPPFLAGS="-I$inn_$1[]_includedir"], 60 [AS_IF([test x"$inn_$1[]_root" != x], 61 [AS_IF([test x"$inn_$1[]_root" != x/usr], 62 [$1[]_CPPFLAGS="-I${inn_$1[]_root}/include"])])])]) 63 64dnl Check whether a library works. This is used as a sanity check on the 65dnl results of *-config shell scripts. Takes four arguments; the first, if 66dnl "true", says that a working library is mandatory and errors out if it 67dnl doesn't. The second is the variable prefix. The third is a function to 68dnl look for that should be in the libraries. The fourth is the 69dnl human-readable name of the library for error messages. 70AC_DEFUN([INN_LIB_HELPER_CHECK], 71[INN_LIB_HELPER_SWITCH([$2]) 72 AC_CHECK_FUNC([$3], [], 73 [AS_IF([test x"$1" = xtrue], 74 [AC_MSG_FAILURE([unable to link with $4 library])]) 75 $2[]_CPPFLAGS= 76 $2[]_LDFLAGS= 77 $2[]_LIBS=]) 78 INN_LIB_HELPER_RESTORE([$2])]) 79 80dnl Initialize the variables used by a library probe and set the appropriate 81dnl ones as substitution variables. Takes the library variable prefix as its 82dnl only argument. 83AC_DEFUN([INN_LIB_HELPER_VAR_INIT], 84[inn_$1[]_root= 85 inn_$1[]_libdir= 86 inn_$1[]_includedir= 87 inn_use_$1= 88 $1[]_CPPFLAGS= 89 $1[]_LDFLAGS= 90 $1[]_LIBS= 91 AC_SUBST([$1][_CPPFLAGS]) 92 AC_SUBST([$1][_LDFLAGS]) 93 AC_SUBST([$1][_LIBS])]) 94 95dnl Unset all of the variables used by a library probe. Used with the 96dnl _OPTIONAL versions of header probes when a header or library wasn't found 97dnl and therefore the library isn't usable. 98AC_DEFUN([INN_LIB_HELPER_VAR_CLEAR], 99[$1[]_CPPFLAGS= 100 $1[]_LDFLAGS= 101 $1[]_LIBS=]) 102 103dnl Handles --with options for a non-optional library. First argument is the 104dnl base for the switch names. Second argument is the short description. 105dnl Third argument is the variable prefix. The variables set are used by 106dnl INN_LIB_HELPER_PATHS. 107AC_DEFUN([INN_LIB_HELPER_WITH], 108[AC_ARG_WITH([$1], 109 [AS_HELP_STRING([--with-][$1][=DIR], 110 [Location of $2 headers and libraries])], 111 [AS_IF([test x"$withval" != xyes && test x"$withval" != xno], 112 [inn_$3[]_root="$withval"])]) 113 AC_ARG_WITH([$1][-include], 114 [AS_HELP_STRING([--with-][$1][-include=DIR], 115 [Location of $2 headers])], 116 [AS_IF([test x"$withval" != xyes && test x"$withval" != xno], 117 [inn_$3[]_includedir="$withval"])]) 118 AC_ARG_WITH([$1][-lib], 119 [AS_HELP_STRING([--with-][$1][-lib=DIR], 120 [Location of $2 libraries])], 121 [AS_IF([test x"$withval" != xyes && test x"$withval" != xno], 122 [inn_$3[]_libdir="$withval"])])]) 123 124dnl Handles --with options for an optional library, so --with-<library> can 125dnl cause the checks to be skipped entirely or become mandatory. Sets an 126dnl inn_use_PREFIX variable to true or false if the library is explicitly 127dnl enabled or disabled. 128dnl 129dnl First argument is the base for the switch names. Second argument is the 130dnl short description. Third argument is the variable prefix. 131dnl 132dnl The variables set are used by INN_LIB_HELPER_PATHS. 133AC_DEFUN([INN_LIB_HELPER_WITH_OPTIONAL], 134[AC_ARG_WITH([$1], 135 [AS_HELP_STRING([--with-][$1][@<:@=DIR@:>@], 136 [Location of $2 headers and libraries])], 137 [AS_IF([test x"$withval" = xno], 138 [inn_use_$3=false], 139 [AS_IF([test x"$withval" != xyes], [inn_$3[]_root="$withval"]) 140 inn_use_$3=true])]) 141 AC_ARG_WITH([$1][-include], 142 [AS_HELP_STRING([--with-][$1][-include=DIR], 143 [Location of $2 headers])], 144 [AS_IF([test x"$withval" != xyes && test x"$withval" != xno], 145 [inn_$3[]_includedir="$withval"])]) 146 AC_ARG_WITH([$1][-lib], 147 [AS_HELP_STRING([--with-][$1][-lib=DIR], 148 [Location of $2 libraries])], 149 [AS_IF([test x"$withval" != xyes && test x"$withval" != xno], 150 [inn_$3[]_libdir="$withval"])])]) 151