Remove Readline library integration

This removes the GNU Readline library integration and relies on the
libedit library if present. Issue is that there are several ext/readline
libraries and GNU Readline license (GNU GPL 3) is not compatible with
the PHP license. There was a similar attempt to fix this (GH-3823) and
now fix continues here.

Changes:
- `--with-libedit` configure option removed (only `--with-readline`
  stays)
- readline extension tests fixed: those required by only readline
  library removed, added missing skip reasons, some functions are always
  available, etc.
- New PHP_SETUP_EDIT Autoconf macro that finds libedit

This also fixes the phpdbg readline integration on *nix systems (using
libedit library) for history (up/down keys and similar nice features) to
not produce compile errors:

    ./configure --enable-phpdbg-readline
    make

    undefined reference to 'readline'
    undefined reference to 'add_history'

.circleci/config.yml

@@ -57,7 +57,7 @@ jobs:
               libxml2-dev \
               libxslt1-dev \
               libpq-dev \
-              libreadline-dev \
+              libedit-dev \
               libldap2-dev \
               libsodium-dev \
               libargon2-0-dev \

.github/actions/apk/action.yml

@@ -41,7 +41,7 @@ runs:
             libzip-dev \
             oniguruma-dev \
             openssl-dev \
-            readline-dev \
+            libedit-dev \
             sqlite-dev \
             tidyhtml-dev \
             krb5-dev \

.github/actions/apt-x32/action.yml

@@ -28,7 +28,7 @@ runs:
           libonig-dev:i386 \
           libpng-dev:i386 \
           libpq-dev:i386 \
-          libreadline-dev:i386 \
+          libedit-dev:i386 \
           libsasl2-dev:i386 \
           libsodium-dev:i386 \
           libsqlite3-dev:i386 \

.github/actions/configure-macos/action.yml

@@ -45,7 +45,7 @@ runs:
           --enable-sysvshm \
           --enable-shmop \
           --enable-pcntl \
-          --with-readline="$BREW_OPT"/readline \
+          --with-readline \
           --enable-mbstring \
           --with-curl \
           --with-gettext="$BREW_OPT"/gettext \

.github/actions/configure-x64/action.yml

@@ -41,7 +41,7 @@ runs:
           --enable-sysvshm \
           --enable-shmop \
           --enable-pcntl \
-          --without-readline --with-libedit \
+          --with-readline \
           --enable-mbstring \
           --with-curl \
           --with-gettext \

build/php.m4

@@ -2002,6 +2002,25 @@ $2],
 ]))])])
 ])
 
+dnl
+dnl
+dnl PHP_SETUP_EDIT([shared-add], [action-if-found], [action-if-not-found], [not-extension])
+dnl
+dnl Common setup macro for linking libedit library. If "not-extension" argument
+dnl is passed, the found library is appended to the "shared-add" variable
+dnl unconditionally (for SAPIs).
+dnl
+AC_DEFUN([PHP_SETUP_EDIT], [
+PKG_CHECK_MODULES([EDIT], [libedit], [
+  PHP_EVAL_INCLINE([$EDIT_CFLAGS])
+  PHP_EVAL_LIBLINE([$EDIT_LIBS], [$1], [$4])
+  AC_DEFINE([HAVE_LIBEDIT], [1],
+    [Define to 1 if 'libedit' library is available.])
+  $2
+],
+[$3])
+])
+
 dnl ----------------------------------------------------------------------------
 dnl Misc. macros
 dnl ----------------------------------------------------------------------------

ext/readline/config.m4

@@ -1,103 +1,17 @@
-PHP_ARG_WITH([libedit],
-  [for libedit readline replacement],
-  [AS_HELP_STRING([--with-libedit],
-    [Include libedit readline replacement (CLI/CGI only)])])
+PHP_ARG_WITH([readline],
+  [for readline support],
+  [AS_HELP_STRING([--with-readline],
+    [Include readline support using the libedit library (CLI/CGI only)])])
 
-if test "$PHP_LIBEDIT" = "no"; then
-  PHP_ARG_WITH([readline],
-    [for readline support],
-    [AS_HELP_STRING([[--with-readline[=DIR]]],
-      [Include readline support (CLI/CGI only)])])
-else
-  dnl "register" the --with-readline option to prevent invalid "unknown
-  dnl configure option" warning
-  php_with_readline=no
-fi
-
-if test "$PHP_READLINE" && test "$PHP_READLINE" != "no"; then
-  for i in $PHP_READLINE /usr/local /usr; do
-    AS_IF([test -f $i/include/readline/readline.h], [READLINE_DIR=$i; break;])
-  done
-
-  AS_VAR_IF([READLINE_DIR],,
-    [AC_MSG_ERROR([Please reinstall readline - I cannot find readline.h])])
-
-  PHP_ADD_INCLUDE([$READLINE_DIR/include])
-
-  PHP_READLINE_LIBS=""
-  AC_CHECK_LIB([ncurses], [tgetent], [
-    PHP_ADD_LIBRARY([ncurses],, [READLINE_SHARED_LIBADD])
-    PHP_READLINE_LIBS="$PHP_READLINE_LIBS -lncurses"
-    ],
-    [AC_CHECK_LIB([termcap], [tgetent], [
-      PHP_ADD_LIBRARY([termcap],, [READLINE_SHARED_LIBADD])
-      PHP_READLINE_LIBS="$PHP_READLINE_LIBS -ltermcap"
-    ])
-  ])
-
-  PHP_CHECK_LIBRARY([readline], [readline],
-    [PHP_ADD_LIBRARY_WITH_PATH([readline],
-      [$READLINE_DIR/$PHP_LIBDIR],
-      [READLINE_SHARED_LIBADD])],
-    [AC_MSG_FAILURE([The readline library not found.])],
-    [-L$READLINE_DIR/$PHP_LIBDIR $PHP_READLINE_LIBS])
-
-  PHP_CHECK_LIBRARY([readline], [rl_callback_read_char],
-    [AC_DEFINE([HAVE_RL_CALLBACK_READ_CHAR], [1])],
-    [],
-    [-L$READLINE_DIR/$PHP_LIBDIR $PHP_READLINE_LIBS])
-
-  PHP_CHECK_LIBRARY([readline], [rl_on_new_line],
-    [AC_DEFINE([HAVE_RL_ON_NEW_LINE], [1])],
-    [],
-    [-L$READLINE_DIR/$PHP_LIBDIR $PHP_READLINE_LIBS])
-
-  PHP_CHECK_LIBRARY([readline], [rl_completion_matches],
-    [AC_DEFINE([HAVE_RL_COMPLETION_MATCHES], [1])],
-    [],
-    [-L$READLINE_DIR/$PHP_LIBDIR $PHP_READLINE_LIBS])
-
-  CFLAGS_SAVE=$CFLAGS
-  LDFLAGS_SAVE=$LDFLAGS
-  LIBS_SAVE=$LIBS
-  CFLAGS="$CFLAGS $INCLUDES"
-  LDFLAGS="$LDFLAGS -L$READLINE_DIR/$PHP_LIBDIR"
-  LIBS="$LIBS -lreadline"
-
-  dnl Sanity and minimum version check if readline library has variable
-  dnl rl_pending_input.
-  AC_CHECK_DECL([rl_pending_input],, [AC_MSG_FAILURE([
-      Invalid readline installation detected. Try --with-libedit instead.
-    ])], [
-      #include <stdio.h>
-      #include <readline/readline.h>
-    ])
-
-  AC_CHECK_DECL([rl_erase_empty_line],
-    [AC_DEFINE([HAVE_ERASE_EMPTY_LINE], [1])],, [
-      #include <stdio.h>
-      #include <readline/readline.h>
-    ])
-  CFLAGS=$CFLAGS_SAVE
-  LDFLAGS=$LDFLAGS_SAVE
-  LIBS=$LIBS_SAVE
+if test "$PHP_READLINE" != "no"; then
+  AS_VAR_IF([PHP_READLINE], [yes],,
+    [AC_MSG_WARN([m4_text_wrap([
+      The directory argument is not supported anymore, rely on pkg-config.
+      Replace '--with-readline=$PHP_READLINE' with '--with-realine' and use
+      environment variables 'PKG_CONFIG_PATH', 'EDIT_LIBS', or 'EDIT_CFLAGS'.
+    ])])])
 
-  AC_DEFINE([HAVE_HISTORY_LIST], [1])
-  AC_DEFINE([HAVE_LIBREADLINE], [1],
-    [Define to 1 if readline extension uses the 'readline' library.])
-
-elif test "$PHP_LIBEDIT" != "no"; then
-  AS_VAR_IF([PHP_LIBEDIT], [yes],,
-    [AC_MSG_WARN(m4_text_wrap([
-      The libedit directory argument is not supported anymore, rely on
-      pkg-config. Replace '--with-libedit=$PHP_LIBEDIT' with '--with-libedit'
-      and use environment variables 'PKG_CONFIG_PATH', 'EDIT_LIBS', or
-      'EDIT_CFLAGS'.
-    ]))])
-
-  PKG_CHECK_MODULES([EDIT], [libedit])
-  PHP_EVAL_LIBLINE([$EDIT_LIBS], [READLINE_SHARED_LIBADD])
-  PHP_EVAL_INCLINE([$EDIT_CFLAGS])
+  PHP_SETUP_EDIT([READLINE_SHARED_LIBADD])
 
   AC_CHECK_LIB([ncurses], [tgetent],
     [PHP_ADD_LIBRARY([ncurses],, [READLINE_SHARED_LIBADD])],
@@ -111,28 +25,26 @@ elif test "$PHP_LIBEDIT" != "no"; then
 
   PHP_CHECK_LIBRARY([edit], [rl_callback_read_char],
     [AC_DEFINE([HAVE_RL_CALLBACK_READ_CHAR], [1],
-      [Define to 1 if edit/readline library has the 'rl_callback_read_char'
-      function.])],
+      [Define to 1 if edit library has the 'rl_callback_read_char' function.])],
     [],
     [$READLINE_SHARED_LIBADD])
 
   PHP_CHECK_LIBRARY([edit], [rl_on_new_line],
     [AC_DEFINE([HAVE_RL_ON_NEW_LINE], [1],
-      [Define to 1 if edit/readline library has the 'rl_on_new_line'
-      function.])],
+      [Define to 1 if edit library has the 'rl_on_new_line' function.])],
     [],
     [$READLINE_SHARED_LIBADD])
 
   PHP_CHECK_LIBRARY([edit], [rl_completion_matches],
     [AC_DEFINE([HAVE_RL_COMPLETION_MATCHES], [1],
-      [Define to 1 if edit/readline library has the 'rl_completion_matches'
+      [Define to 1 if edit library has the 'rl_completion_matches'
       function.])],
     [],
     [$READLINE_SHARED_LIBADD])
 
   PHP_CHECK_LIBRARY([edit], [history_list],
     [AC_DEFINE([HAVE_HISTORY_LIST], [1],
-      [Define to 1 if edit/readline library has the 'history_list' function.])],
+      [Define to 1 if edit library has the 'history_list' function.])],
     [],
     [$READLINE_SHARED_LIBADD])
 
@@ -142,17 +54,12 @@ elif test "$PHP_LIBEDIT" != "no"; then
   LIBS="$LIBS $EDIT_LIBS"
   AC_CHECK_DECL([rl_erase_empty_line],
     [AC_DEFINE([HAVE_ERASE_EMPTY_LINE], [1],
-      [Define to 1 if edit/readline library has the 'rl_erase_empty_line'
-      global variable.])],,
+      [Define to 1 if edit library has the 'rl_erase_empty_line' global
+      variable.])],,
     [#include <editline/readline.h>])
   CFLAGS=$CFLAGS_SAVE
   LIBS=$LIBS_SAVE
 
-  AC_DEFINE([HAVE_LIBEDIT], [1],
-    [Define to 1 if readline extension uses the 'libedit' library.])
-fi
-
-if test "$PHP_READLINE" != "no" || test "$PHP_LIBEDIT" != "no"; then
   dnl Add -Wno-strict-prototypes as depends on user libs
   PHP_NEW_EXTENSION([readline],
     [readline.c readline_cli.c],

ext/readline/php_readline.h

@@ -20,10 +20,10 @@
 #ifdef HAVE_LIBEDIT
 #define READLINE_LIB "libedit"
 #else
-#define READLINE_LIB "readline"
+#define READLINE_LIB ""
 #endif
 
-#if defined(HAVE_LIBREADLINE) || defined(HAVE_LIBEDIT)
+#ifdef HAVE_LIBEDIT
 
 extern zend_module_entry readline_module_entry;
 #define phpext_readline_ptr &readline_module_entry
@@ -35,6 +35,6 @@ extern zend_module_entry readline_module_entry;
 
 #define phpext_readline_ptr NULL
 
-#endif /* HAVE_LIBREADLINE */
+#endif /* HAVE_LIBEDIT */
 
 #endif /* PHP_READLINE_H */