config: document git config getter return value

diff --git a/configure.ac b/configure.ac
index e33b6c79c0d120fcbda00ce14cc461d6de71c690..e11b7976ab1c93d8ccec2e499d0093db42551059 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -241,7 +241,6 @@ AC_MSG_NOTICE([CHECKS for site configuration])
 # a bundled SHA1 routine optimized for PowerPC.
 #
 # Define NO_OPENSSL environment variable if you do not have OpenSSL.
-# This also implies BLK_SHA1.
 #
 # Define OPENSSLDIR=/foo/bar if your openssl header and library files are in
 # /foo/bar/include and /foo/bar/lib directories.
@@ -250,24 +249,70 @@ AS_HELP_STRING([--with-openssl],[use OpenSSL library (default is YES)])
 AS_HELP_STRING([],              [ARG can be prefix for openssl library and headers]),
 GIT_PARSE_WITH([openssl]))
 
-# Define USE_LIBPCRE if you have and want to use libpcre. git-grep will be
-# able to use Perl-compatible regular expressions.
+# Define USE_LIBPCRE if you have and want to use libpcre. Various
+# commands such as log and grep offer runtime options to use
+# Perl-compatible regular expressions instead of standard or extended
+# POSIX regular expressions.
 #
-# Define LIBPCREDIR=/foo/bar if your libpcre header and library files are in
+# USE_LIBPCRE is a synonym for USE_LIBPCRE2, define USE_LIBPCRE1
+# instead if you'd like to use the legacy version 1 of the PCRE
+# library. Support for version 1 will likely be removed in some future
+# release of Git, as upstream has all but abandoned it.
+#
+# Define LIBPCREDIR=/foo/bar if your PCRE header and library files are in
 # /foo/bar/include and /foo/bar/lib directories.
 #
 AC_ARG_WITH(libpcre,
-AS_HELP_STRING([--with-libpcre],[support Perl-compatible regexes (default is NO)])
+AS_HELP_STRING([--with-libpcre],[synonym for --with-libpcre2]),
+    if test "$withval" = "no"; then
+       USE_LIBPCRE2=
+    elif test "$withval" = "yes"; then
+       USE_LIBPCRE2=YesPlease
+    else
+       USE_LIBPCRE2=YesPlease
+       LIBPCREDIR=$withval
+       AC_MSG_NOTICE([Setting LIBPCREDIR to $LIBPCREDIR])
+        dnl USE_LIBPCRE2 can still be modified below, so don't substitute
+        dnl it yet.
+       GIT_CONF_SUBST([LIBPCREDIR])
+    fi)
+
+AC_ARG_WITH(libpcre1,
+AS_HELP_STRING([--with-libpcre1],[support Perl-compatible regexes via libpcre1 (default is NO)])
+AS_HELP_STRING([],           [ARG can be also prefix for libpcre library and headers]),
+    if test "$withval" = "no"; then
+       USE_LIBPCRE1=
+    elif test "$withval" = "yes"; then
+       USE_LIBPCRE1=YesPlease
+    else
+       USE_LIBPCRE1=YesPlease
+       LIBPCREDIR=$withval
+       AC_MSG_NOTICE([Setting LIBPCREDIR to $LIBPCREDIR])
+        dnl USE_LIBPCRE1 can still be modified below, so don't substitute
+        dnl it yet.
+       GIT_CONF_SUBST([LIBPCREDIR])
+    fi)
+
+AC_ARG_WITH(libpcre2,
+AS_HELP_STRING([--with-libpcre2],[support Perl-compatible regexes via libpcre2 (default is NO)])
 AS_HELP_STRING([],           [ARG can be also prefix for libpcre library and headers]),
+    if test -n "$USE_LIBPCRE2"; then
+        AC_MSG_ERROR([Only supply one of --with-libpcre or its synonym --with-libpcre2!])
+    fi
+
+    if test -n "$USE_LIBPCRE1"; then
+        AC_MSG_ERROR([Only supply one of --with-libpcre1 or --with-libpcre2!])
+    fi
+
     if test "$withval" = "no"; then
-       USE_LIBPCRE=
+       USE_LIBPCRE2=
     elif test "$withval" = "yes"; then
-       USE_LIBPCRE=YesPlease
+       USE_LIBPCRE2=YesPlease
     else
-       USE_LIBPCRE=YesPlease
+       USE_LIBPCRE2=YesPlease
        LIBPCREDIR=$withval
        AC_MSG_NOTICE([Setting LIBPCREDIR to $LIBPCREDIR])
-        dnl USE_LIBPCRE can still be modified below, so don't substitute
+        dnl USE_LIBPCRE2 can still be modified below, so don't substitute
         dnl it yet.
        GIT_CONF_SUBST([LIBPCREDIR])
     fi)
@@ -499,21 +544,36 @@ GIT_CONF_SUBST([NEEDS_SSL_WITH_CRYPTO])
 GIT_CONF_SUBST([NO_OPENSSL])
 
 #
-# Define USE_LIBPCRE if you have and want to use libpcre. git-grep will be
-# able to use Perl-compatible regular expressions.
+# Handle the USE_LIBPCRE1 and USE_LIBPCRE2 options potentially set
+# above.
 #
 
-if test -n "$USE_LIBPCRE"; then
+if test -n "$USE_LIBPCRE1"; then
 
 GIT_STASH_FLAGS($LIBPCREDIR)
 
 AC_CHECK_LIB([pcre], [pcre_version],
-[USE_LIBPCRE=YesPlease],
-[USE_LIBPCRE=])
+[USE_LIBPCRE1=YesPlease],
+[USE_LIBPCRE1=])
+
+GIT_UNSTASH_FLAGS($LIBPCREDIR)
+
+GIT_CONF_SUBST([USE_LIBPCRE1])
+
+fi
+
+
+if test -n "$USE_LIBPCRE2"; then
+
+GIT_STASH_FLAGS($LIBPCREDIR)
+
+AC_CHECK_LIB([pcre2-8], [pcre2_config_8],
+[USE_LIBPCRE2=YesPlease],
+[USE_LIBPCRE2=])
 
 GIT_UNSTASH_FLAGS($LIBPCREDIR)
 
-GIT_CONF_SUBST([USE_LIBPCRE])
+GIT_CONF_SUBST([USE_LIBPCRE2])
 
 fi