config: Introduce functions to write non-standard file

diff --git a/configure.ac b/configure.ac
index fafd81557c2d3dd17cb1c15c545f3602a3a0c6bf..048a1d4972769184ff857fb7681bc67b2ebdfb99 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -220,6 +220,27 @@ 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 LIBPCREDIR=/foo/bar if your libpcre 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([],           [ARG can be also prefix for libpcre library and headers]),
+if test "$withval" = "no"; then \
+       USE_LIBPCRE=; \
+elif test "$withval" = "yes"; then \
+       USE_LIBPCRE=YesPlease; \
+else
+       USE_LIBPCRE=YesPlease; \
+       LIBPCREDIR=$withval; \
+       AC_MSG_NOTICE([Setting LIBPCREDIR to $withval]); \
+       GIT_CONF_APPEND_LINE(LIBPCREDIR=$withval); \
+fi \
+)
+#
 # Define NO_CURL if you do not have curl installed.  git-http-pull and
 # git-http-push are not built, and you cannot use http:// and https://
 # transports.
@@ -434,6 +455,25 @@ GIT_UNSTASH_FLAGS($OPENSSLDIR)
 AC_SUBST(NEEDS_SSL_WITH_CRYPTO)
 AC_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.
+#
+
+if test -n "$USE_LIBPCRE"; then
+
+GIT_STASH_FLAGS($LIBPCREDIR)
+
+AC_CHECK_LIB([pcre], [pcre_version],
+[USE_LIBPCRE=YesPlease],
+[USE_LIBPCRE=])
+
+GIT_UNSTASH_FLAGS($LIBPCREDIR)
+
+AC_SUBST(USE_LIBPCRE)
+
+fi
+
 #
 # Define NO_CURL if you do not have libcurl installed.  git-http-pull and
 # git-http-push are not built, and you cannot use http:// and https://