Autotools: Enhance PHP_EVAL_LIBLINE M4 macro (#14924)

PHP_EVAL_LIBALINE macro processes the given libraries flags (-l) and/or
library paths flags (-L) and appends the -l flags to either LIBS or the
given *_SHARED_LIBADD variables. The -L flags are appended to the
LDFLAGS. The new 3rd argument enables appending libraries to the given
variable in the 2nd argument without manual setting whether the
extension is shared. For example, to simplify usage in SAPIs where
additional libraries need to be appended but they shouldn't go to the
global LIBS. This can be then used in PHP-FPM SAPI to link apparmor,
SELinux, systemd, etc.

Author: petk

UPGRADING.INTERNALS

@@ -160,6 +160,8 @@ PHP 8.4 INTERNALS UPGRADE NOTES
    - PDO extensions in php-src don't have the include flag -I$pdo_cv_inc_path
      directory anymore.
    - M4 macro PHP_SETUP_OPENSSL doesn't accept the 3rd argument anymore.
+   - M4 macro PHP_EVAL_LIBLINE got a new 3rd argument to override the ext_shared
+     checks.
    - TSRM/tsrm.m4 file and its TSRM_CHECK_PTHREADS M4 macro have been removed.
    - Added pkg-config support to find libpq for the pdo_pgsql and pgsql
      extensions. The libpq paths can be customized with the PGSQL_CFLAGS and

build/php.m4

@@ -341,12 +341,21 @@ AC_DEFUN([PHP_REMOVE_USR_LIB],[
 ])
 
 dnl
-dnl PHP_EVAL_LIBLINE(libline, SHARED-LIBADD)
-dnl
-dnl Use this macro, if you need to add libraries and or library search paths to
-dnl the PHP build system which are only given in compiler notation.
-dnl
-AC_DEFUN([PHP_EVAL_LIBLINE],[
+dnl PHP_EVAL_LIBLINE(libline, [libs-variable], [not-extension])
+dnl
+dnl Use this macro to add libraries and/or library search paths to the PHP build
+dnl system when specified in compiler notation. Libraries (-l) are appended
+dnl either to the global Autoconf LIBS variable or to the specified
+dnl "libs-variable" (e.g., *_SHARED_LIBADD) when the extension is shared
+dnl (ext_shared=yes). If "not-extension" is set to a non-blank value, the
+dnl libraries are appended to "libs-variable" unconditionally (this is
+dnl particularly useful when working with SAPIs). The -L flags are appended to
+dnl the LDFLAGS.
+dnl
+AC_DEFUN([PHP_EVAL_LIBLINE],
+[m4_ifnblank([$3], [m4_ifblank([$2],
+  [m4_warn([syntax], [Missing 2nd argument when skipping extension check])],
+  [_php_ext_shared_saved=$ext_shared; ext_shared=yes])])
   for ac_i in $1; do
     case $ac_i in
     -pthread[)]
@@ -368,6 +377,7 @@ AC_DEFUN([PHP_EVAL_LIBLINE],[
     ;;
     esac
   done
+m4_ifnblank([$3], [m4_ifnblank([$2], [ext_shared=$_php_ext_shared_saved])])dnl
 ])
 
 dnl