build: allow building with a handful of GSSAPI implementations

Author: jengelh

configure.ac

@@ -118,7 +118,12 @@ PKG_CHECK_MODULES([gss], [krb5-gssapi], [
 	AC_DEFINE([HAVE_GSSAPI], [1])
 	have_gssapi=1
 ], [
-	have_gssapi=0
+	PKG_CHECK_MODULES([gss], [libgssglue], [
+		AC_DEFINE([HAVE_GSSAPI], [1])
+		have_gssapi=1
+	], [
+		have_gssapi=0
+	])
 ])
 PKG_CHECK_MODULES([libHX], [libHX >= 4.28])
 PKG_CHECK_MODULES([libcrypto], [libcrypto])

doc/install.rst

@@ -34,6 +34,12 @@ Optional deps:
   * libc/libresolv with interface "res_nquery" & "ns_initparse" functions
   * c-ares
 * cURL library
+* GSSAPI library
+  * mit-krb5-gssapi or
+  * heimdal-gssapi or
+  * libgssglue
+  * (even if built with any, you can still use external helpers like
+    ``/usr/libexec/squid/negotiate_wrapper_auth`` from Gromox)
 * mit-krb5-gssapi
 * libesedb
 * libolecf