diff options
| -rw-r--r-- | libgphoto2_port/gphoto-m4/gp-libjpeg.m4 | 99 |
1 files changed, 76 insertions, 23 deletions
diff --git a/libgphoto2_port/gphoto-m4/gp-libjpeg.m4 b/libgphoto2_port/gphoto-m4/gp-libjpeg.m4 index e707408d1..a60a15f03 100644 --- a/libgphoto2_port/gphoto-m4/gp-libjpeg.m4 +++ b/libgphoto2_port/gphoto-m4/gp-libjpeg.m4 @@ -2,9 +2,14 @@ dnl #################################################################### dnl GP_LIBJPEG dnl #################################################################### dnl +dnl Define the libjpeg related compile and linker flags depending on +dnl configure arguments and availability on the system. +dnl dnl * If --without-jpeg or --with-jpeg=no is given, build without dnl libjpeg support. -dnl * If not explicitly disabled by --without-jpeg, autodetect libjpeg. +dnl +dnl * If --with-jpeg=auto or --with-jpeg=autodetect is given, +dnl autodetect libjpeg: dnl * If any of LIBJPEG_(CFLAGS|LIBS) is explicitly given, try dnl compile+link using that. dnl * If compile+link works, use that. @@ -18,28 +23,87 @@ dnl * If libjpeg.pc has not been found, try default location. dnl * If compile+link works, use that. dnl * If compile+link fails, build without libjpeg. dnl +dnl * If --with-jpeg or --with-jpeg=yes is given, autodetect as +dnl described above, but abort with an error message if libjpeg +dnl could not be found. +dnl +dnl * If neither --with-jpeg nor --without-jpeg are explicitly given, +dnl run the above autodetect sequence. +dnl AC_DEFUN([GP_LIBJPEG], [dnl dnl AC_MSG_CHECKING([whether to build with libjpeg]) AC_ARG_WITH([jpeg], [AS_HELP_STRING([--without-jpeg], - [Build without libjpeg (default: with libjpeg)])], - [dnl just keep the with-jpeg however it is given - AS_VAR_IF([with_jpeg], [no], [], [dnl - AC_MSG_ERROR([ -Unhandled value given to --with-jpeg / --without-jpeg: '$with_jpeg' -]) - ]) -], [dnl - with_jpeg=autodetect + [Build without libjpeg (default: autodetect)])], + [dnl Normalize --with-jpeg=ARG argument value + AS_CASE([$with_jpeg], + [autodetect], [with_jpeg=auto], + ) +], [dnl Default value + with_jpeg=auto ]) +dnl AC_MSG_RESULT([$with_jpeg]) dnl -AS_VAR_IF([with_jpeg], [no], [dnl Not using libjpeg, so no checks are needed +AS_CASE([$with_jpeg], +[no], [ # libjpeg explictly disabled from command line GP_CONFIG_MSG([JPEG mangling support], [no (disabled by --without-jpeg)]) -], [dnl +], +[auto|yes], [ + GP_LIBJPEG_AUTODETECT + + AS_VAR_IF([have_libjpeg], [no], [dnl + AS_VAR_IF([with_jpeg], [yes], [dnl + AC_MSG_ERROR([ +libjpeg has been requested explicitly (--with-jpeg=yes), but could not be +found and made to work. +]) + ], [dnl + GP_CONFIG_MSG([JPEG mangling support], + [${have_libjpeg} (could not find working libjpeg)]) + ]) + ], [dnl + AC_DEFINE([HAVE_LIBJPEG], [1], + [define if building with libjpeg]) + GP_CONFIG_MSG([JPEG mangling support], + [${have_libjpeg}]) + ]) +], +[AC_MSG_ERROR([ +Unhandled value given to --with-jpeg: ${with_jpeg} + +To allow the auto-detection of libjpeg, set up the pkg-config related +environment variables (PKG_CONFIG, PKG_CONFIG_PATH, PKG_CONFIG_LIBDIR) +or have libjpeg installed in the standard location to include from and +link to. + +To force specific compile and link flags for libjpeg, set the +environment variables LIBJPEG_CFLAGS and $LIBJPEG_LIBS accordingly. +]) +]) +])dnl +dnl +dnl +dnl #################################################################### +dnl GP_LIBJPEG_AUTODETECT +dnl +dnl Do the actual autodetection of libjpeg, setting +dnl +dnl have_libjpeg=yes +dnl If libjpeg has been found and can be both compiled with and +dnl linked against. +dnl +dnl have_libjpeg=no +dnl If libjpeg has not been found or cannot be compiled with or +dnl cannot be linked against. +dnl +dnl Used once: By GP_LIBJPEG to make the GP_LIBJPEG code more readable. +dnl #################################################################### +dnl +AC_DEFUN([GP_LIBJPEG_AUTODETECT], [dnl have_libjpeg=no AC_MSG_CHECKING([for libjpeg via variables]) @@ -78,17 +142,6 @@ libjpeg not found despite LIBJPEG_CFLAGS and/or LIBJPEG_LIBS being set. ]) ]) ]) - - AS_VAR_IF([have_libjpeg], [no], [dnl - GP_CONFIG_MSG([JPEG mangling support], - [${have_libjpeg} (requires libjpeg)]) - ], [dnl - AC_DEFINE([HAVE_LIBJPEG], [1], - [define if building with libjpeg]) - GP_CONFIG_MSG([JPEG mangling support], - [${have_libjpeg}]) - ]) -]) ])dnl dnl dnl |