3 # Copyright (c) 2004-2016 Glenn Randers-Pehrson
4 # Last changed in libpng 1.6.25 [September 1, 2016]
6 # This code is released under the libpng license.
7 # For conditions of distribution and use, see the disclaimer
10 dnl Process this file with autoconf to produce a configure script.
12 dnl Minor upgrades (compatible ABI): increment the package version
13 dnl (third field in two places below) and set the PNGLIB_RELEASE
16 dnl Major upgrades (incompatible ABI): increment the package major
17 dnl version (second field, or first if desired), set the minor
18 dnl to 0, set PNGLIB_MAJOR below *and* follow the instructions in
19 dnl Makefile.am to upgrade the package name.
21 dnl This is here to prevent earlier autoconf from being used, it
22 dnl should not be necessary to regenerate configure if the time
23 dnl stamps are correct
26 dnl Version number stuff here:
28 AC_INIT([libpng],[1.6.27],[png-mng-implement@lists.sourceforge.net])
29 AC_CONFIG_MACRO_DIR([scripts])
31 # libpng does not follow GNU file name conventions (hence 'foreign')
32 # color-tests requires automake 1.11 or later
33 # silent-rules requires automake 1.11 or later
34 # dist-xz requires automake 1.11 or later
35 # 1.12.2 fixes a security issue in 1.11.2 and 1.12.1
36 # 1.13 is required for parallel tests
37 AM_INIT_AUTOMAKE([1.13 foreign dist-xz color-tests silent-rules subdir-objects])
38 # The following line causes --disable-maintainer-mode to be the default to
39 # configure. This is necessary because libpng distributions cannot rely on the
40 # time stamps of the autotools generated files being correct
43 dnl configure.ac and Makefile.am expect automake 1.11.2 or a compatible later
44 dnl version; aclocal.m4 will generate a failure if you use a prior version of
45 dnl automake, so the following is not necessary (and is not defined anyway):
46 dnl AM_PREREQ([1.11.2])
47 dnl stop configure from automagically running automake
54 dnl End of version number stuff
56 AC_CONFIG_SRCDIR([pngget.c])
57 AC_CONFIG_HEADERS([config.h])
59 # Checks for programs.
70 dnl libtool/libtoolize; version 2.4.2 is the tested version. This or any
71 dnl compatible later version may be used
75 # Some awks crash when confronted with pnglibconf.dfa, do a test run now
76 # to make sure this doesn't happen
77 AC_MSG_CHECKING([that AWK works])
78 if ${AWK} -f ${srcdir}/scripts/options.awk out="/dev/null" version=search\
79 ${srcdir}/pngconf.h ${srcdir}/scripts/pnglibconf.dfa\
80 ${srcdir}/pngusr.dfa 1>&2
84 AC_MSG_FAILURE([failed], 1)
87 # This is a remnant of the old cc -E validation, where it may have been
88 # necessary to use a different preprocessor for .dfn files
92 # -Werror cannot be passed to GCC in CFLAGS because configure will fail (it
93 # checks the compiler with a program that generates a warning), add the
94 # following option to deal with this
96 [additional flags for the C compiler, use this for options that would]
97 [cause configure itself to fail])
99 AS_HELP_STRING([[[--enable-werror[=OPT]]]],
100 [Pass -Werror or the given argument to the compiler if it is supported]),
101 [test "$enable_werror" = "yes" && enable_werror="-Werror"
102 if test "$enable_werror" != "no"; then
104 CFLAGS="$enable_werror $CFLAGS"
105 AC_MSG_CHECKING([if the compiler allows $enable_werror])
108 [int main(int argc, char **argv){]
109 [return argv[argc-1][0];]
112 PNG_COPTS="$PNG_COPTS $enable_werror",
117 # For GCC 5 the default mode for C is -std=gnu11 instead of -std=gnu89
118 # In pngpriv.h we request just the POSIX 1003.1 and C89 APIs by defining _POSIX_SOURCE to 1
119 # This is incompatible with the new default mode, so we test for that and force the
120 # "-std=c89" compiler option:
121 AC_MSG_CHECKING([if we need to force back C standard to C89])
124 [#define _POSIX_SOURCE 1]
128 if test "x$GCC" != "xyes"; then
130 [Forcing back to C89 is required but the flags are only known for GCC])
133 CFLAGS="$CFLAGS -std=c89"
136 # Checks for header files.
139 # Checks for typedefs, structures, and compiler characteristics.
145 # Checks for library functions.
147 AC_CHECK_FUNCS([memset], , AC_MSG_ERROR(memset not found in libc))
148 AC_CHECK_FUNCS([pow], , AC_CHECK_LIB(m, pow, , AC_MSG_ERROR(cannot find pow)) )
150 # Some later POSIX 1003.1 functions are required for test programs, failure here
151 # is soft (the corresponding test program is not built).
152 AC_CHECK_FUNC([clock_gettime],,[AC_MSG_WARN([not building timepng])])
153 AM_CONDITIONAL([HAVE_CLOCK_GETTIME], [test "$ac_cv_func_clock_gettime" = "yes"])
155 AC_ARG_WITH(zlib-prefix,
156 AS_HELP_STRING([[[--with-zlib-prefix]]],
157 [prefix that may have been used in installed zlib]),
158 [ZPREFIX=${withval}],
160 AC_CHECK_LIB(z, zlibVersion, ,
161 AC_CHECK_LIB(z, ${ZPREFIX}zlibVersion, , AC_MSG_ERROR(zlib not installed)))
163 # The following is for pngvalid, to ensure it catches FP errors even on
164 # platforms that don't enable FP exceptions, the function appears in the math
165 # library (typically), it's not an error if it is not found.
166 AC_CHECK_LIB([m], [feenableexcept])
167 AC_CHECK_FUNCS([feenableexcept])
169 AC_MSG_CHECKING([if using Solaris linker])
170 SLD=`$LD --version 2>&1 | grep Solaris`
178 AM_CONDITIONAL(HAVE_SOLARIS_LD, test "$have_solaris_ld" = "yes")
180 AC_MSG_CHECKING([if libraries can be versioned])
181 # Special case for PE/COFF platforms: ld reports
182 # support for version-script, but doesn't actually
183 # DO anything with it.
185 *cygwin* | *mingw32* | *interix* )
186 have_ld_version_script=no
191 if test "$have_solaris_ld" = "yes"; then
192 GLD=`$LD --help < /dev/null 2>&1 | grep 'M mapfile'`
194 GLD=`$LD --help < /dev/null 2>/dev/null | grep version-script`
198 have_ld_version_script=yes
201 have_ld_version_script=no
203 AC_MSG_WARN(*** You have not enabled versioned symbols.)
208 AM_CONDITIONAL(HAVE_LD_VERSION_SCRIPT, test "$have_ld_version_script" = "yes")
210 if test "$have_ld_version_script" = "yes"; then
211 AC_MSG_CHECKING([for symbol prefix])
212 SYMBOL_PREFIX=`echo "PREFIX=__USER_LABEL_PREFIX__" \
213 | ${CPP-${CC-gcc} -E} - 2>&1 \
214 | ${EGREP-grep} "^PREFIX=" \
215 | ${SED-sed} -e "s:^PREFIX=::" -e "s:__USER_LABEL_PREFIX__::"`
216 AC_SUBST(SYMBOL_PREFIX)
217 AC_MSG_RESULT($SYMBOL_PREFIX)
220 # Substitutions for .in files
221 AC_SUBST(PNGLIB_VERSION)
222 AC_SUBST(PNGLIB_MAJOR)
223 AC_SUBST(PNGLIB_MINOR)
224 AC_SUBST(PNGLIB_RELEASE)
226 # Additional arguments (and substitutions)
227 # Allow the pkg-config directory to be set
228 AC_ARG_WITH(pkgconfigdir,
229 AS_HELP_STRING([[[--with-pkgconfigdir]]],
230 [Use the specified pkgconfig dir (default is libdir/pkgconfig)]),
231 [pkgconfigdir=${withval}],
232 [pkgconfigdir='${libdir}/pkgconfig'])
234 AC_SUBST([pkgconfigdir])
235 AC_MSG_NOTICE([[pkgconfig directory is ${pkgconfigdir}]])
237 # Make the *-config binary config scripts optional
238 AC_ARG_WITH(binconfigs,
239 AS_HELP_STRING([[[--with-binconfigs]]],
240 [Generate shell libpng-config scripts as well as pkg-config data]
241 [@<:@default=yes@:>@]),
242 [if test "${withval}" = no; then
244 AC_MSG_NOTICE([[libpng-config scripts will not be built]])
246 binconfigs='${binconfigs}'
248 [binconfigs='${binconfigs}'])
249 AC_SUBST([binconfigs])
251 # Support for prefixes to the API function names; this will generate defines
252 # at the start of the build to rename exported library functions
253 AC_ARG_WITH(libpng-prefix,
254 AS_HELP_STRING([[[--with-libpng-prefix]]],
255 [prefix libpng exported function (API) names with the given value]),
256 [if test "${withval:-no}" != "no"; then
257 AC_SUBST([PNG_PREFIX], [${withval}])
259 AM_CONDITIONAL([DO_PNG_PREFIX], [test "${with_libpng_prefix:-no}" != "no"])
261 # Control over what links are made for installed files. Versioned files are
262 # always installed, when the following options are turned on corresponding
263 # unversioned links are also created (normally as symbolic links):
264 AC_ARG_ENABLE([unversioned-links],
265 AS_HELP_STRING([[[--enable-unversioned-links]]],
266 [Installed libpng header files are placed in a versioned subdirectory]
267 [and installed libpng library (including DLL) files are versioned.]
268 [If this option is enabled unversioned links will be created pointing to]
269 [the corresponding installed files. If you use libpng.pc or]
270 [libpng-config for all builds you do not need these links, but if you]
271 [compile programs directly they will typically #include <png.h> and]
272 [link with -lpng; in that case you need the links.]
273 [The links can be installed manually using 'make install-header-links']
274 [and 'make install-library-links' and can be removed using the]
275 [corresponding uninstall- targets. If you do enable this option every]
276 [libpng 'make install' will recreate the links to point to the just]
277 [installed version of libpng. The default is to create the links;]
278 [use --disable-unversioned-links to change this]))
280 # The AM_CONDITIONAL test is written so that the default is enabled;
281 # --disable-unversioned-links must be given to turn the option off.
282 AM_CONDITIONAL([DO_INSTALL_LINKS],[test "$enable_unversioned_links" != "no"])
284 AC_ARG_ENABLE([unversioned-libpng-pc],
285 AS_HELP_STRING([[[--enable-unversioned-libpng-pc]]],
286 [Install the configuration file 'libpng.pc' as a link to the versioned]
287 [version. This is done by default - use --disable-unversioned-libpng-pc]
289 AM_CONDITIONAL([DO_INSTALL_LIBPNG_PC],
290 [test "$enable_unversioned_libpng_pc" != "no"])
292 AC_ARG_ENABLE([unversioned-libpng-config],
293 AS_HELP_STRING([[[--enable-unversioned-libpng-config]]],
294 [Install the configuration file 'libpng-config' as a link to the]
295 [versioned version. This is done by default - use]
296 [--disable-unversioned-libpng-config to change this.]))
297 AM_CONDITIONAL([DO_INSTALL_LIBPNG_CONFIG],
298 [test "$enable_unversioned_libpng_config" != "no"])
300 # HOST SPECIFIC OPTIONS
301 # =====================
306 # ARM NEON (SIMD) support.
308 AC_ARG_ENABLE([arm-neon],
309 AS_HELP_STRING([[[--enable-arm-neon]]],
310 [Enable ARM NEON optimizations: =no/off, check, api, yes/on:]
311 [no/off: disable the optimizations; check: use internal checking code]
312 [(deprecated and poorly supported); api: disable by default, enable by]
313 [a call to png_set_option; yes/on: turn on unconditionally.]
314 [If not specified: determined by the compiler.]),
315 [case "$enableval" in
317 # disable the default enabling on __ARM_NEON__ systems:
318 AC_DEFINE([PNG_ARM_NEON_OPT], [0],
319 [Disable ARM Neon optimizations])
320 # Prevent inclusion of the assembler files below:
323 AC_DEFINE([PNG_ARM_NEON_CHECK_SUPPORTED], [],
324 [Check for ARM Neon support at run-time]);;
326 AC_DEFINE([PNG_ARM_NEON_API_SUPPORTED], [],
327 [Turn on ARM Neon optimizations at run-time]);;
329 AC_DEFINE([PNG_ARM_NEON_OPT], [2],
330 [Enable ARM Neon optimizations])
331 AC_MSG_WARN([--enable-arm-neon: please specify 'check' or 'api', if]
332 [you want the optimizations unconditionally pass -mfpu=neon]
333 [to the compiler.]);;
335 AC_MSG_ERROR([--enable-arm-neon=${enable_arm_neon}: invalid value])
338 # Add ARM specific files to all builds where the host_cpu is arm ('arm*') or
339 # where ARM optimizations were explicitly requested (this allows a fallback if a
340 # future host CPU does not match 'arm*')
342 AM_CONDITIONAL([PNG_ARM_NEON],
343 [test "$enable_arm_neon" != 'no' &&
346 *) test "$enable_arm_neon" != '';;
352 # MIPS MSA (SIMD) support.
354 AC_ARG_ENABLE([mips-msa],
355 AS_HELP_STRING([[[--enable-mips-msa]]],
356 [Enable MIPS MSA optimizations: =no/off, check, api, yes/on:]
357 [no/off: disable the optimizations; check: use internal checking code]
358 [(deprecated and poorly supported); api: disable by default, enable by]
359 [a call to png_set_option; yes/on: turn on unconditionally.]
360 [If not specified: determined by the compiler.]),
361 [case "$enableval" in
363 # disable the default enabling on __mips_msa systems:
364 AC_DEFINE([PNG_MIPS_MSA_OPT], [0],
365 [Disable MIPS MSA optimizations])
366 # Prevent inclusion of the assembler files below:
369 AC_DEFINE([PNG_MIPS_MSA_CHECK_SUPPORTED], [],
370 [Check for MIPS MSA support at run-time]);;
372 AC_DEFINE([PNG_MIPS_MSA_API_SUPPORTED], [],
373 [Turn on MIPS MSA optimizations at run-time]);;
375 AC_DEFINE([PNG_MIPS_MSA_OPT], [2],
376 [Enable MIPS MSA optimizations])
377 AC_MSG_WARN([--enable-mips-msa: please specify 'check' or 'api', if]
378 [you want the optimizations unconditionally pass '-mmsa -mfp64']
379 [to the compiler.]);;
381 AC_MSG_ERROR([--enable-mips-msa=${enable_mips_msa}: invalid value])
384 # Add MIPS specific files to all builds where the host_cpu is mips ('mips*') or
385 # where MIPS optimizations were explicitly requested (this allows a fallback if a
386 # future host CPU does not match 'mips*')
388 AM_CONDITIONAL([PNG_MIPS_MSA],
389 [test "$enable_mips_msa" != 'no' &&
391 mipsel*|mips64el*) :;;
394 AC_MSG_NOTICE([[Extra options for compiler: $PNG_COPTS]])
396 # Config files, substituting as above
397 AC_CONFIG_FILES([Makefile libpng.pc:libpng.pc.in])
398 AC_CONFIG_FILES([libpng-config:libpng-config.in],
399 [chmod +x libpng-config])