[PATCH 06/25] autofs-5.0.7 - fix compile error with heimdal support enabled

[Ian Kent <raven@themaw.net>]

From: Lan Yixun (dlan) <dennis.yxun@gmail.com>

this patch instroduce a compatible layer between Heimdal and MTT Krb5.
And I slightly rework the original patch to make it more readable.

Upstream Discussion:
  http://thread.gmane.org/gmane.linux.kernel.autofs/4203

Gentoo Bugs:
  https://bugs.gentoo.org/show_bug.cgi?id=210762

Edited by: Ian Kent <raven@themaw.net>
- fix code indentation.
- update configure to include change.

Signed-off-by: Lan Yixun (dlan) <dennis.yxun@gmail.com>
---
 CHANGELOG            |    1 +
 aclocal.m4           |    7 ++++
 configure            |   84 ++++++++++++++++++++++++++++++++++++++++++++++++++
 include/config.h.in  |    3 ++
 modules/cyrus-sasl.c |   39 ++++++++++++++++++++---
 5 files changed, 129 insertions(+), 5 deletions(-)

diff --git a/CHANGELOG b/CHANGELOG
index fe232f4..c77be18 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -58,6 +58,7 @@
 - add after sssd dependency to unit file.
 - dont start readmap unless ready.
 - fix crash due to thread unsafe use of libldap.
+- fix compile error with heimdal support enabled.
 
 25/07/2012 autofs-5.0.7
 =======================
diff --git a/aclocal.m4 b/aclocal.m4
index c5de159..7a8b03c 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -299,6 +299,13 @@ else
   HAVE_KRB5=1
   KRB5_LIBS=`$KRB5_CONFIG --libs`
   KRB5_FLAGS=`$KRB5_CONFIG --cflags`
+
+  SAVE_CFLAGS=$CFLAGS
+  SAVE_LIBS=$LIBS
+  CFLAGS="$CFLAGS $KRB5_FLAGS"
+  LIBS="$LIBS $KRB5_LIBS"
+
+  AC_CHECK_FUNCS([krb5_principal_get_realm])
 fi])
 
 dnl --------------------------------------------------------------------------
diff --git a/configure b/configure
index 08b7ccc..1086eba 100755
--- a/configure
+++ b/configure
@@ -1559,6 +1559,73 @@ fi
 
 } # ac_fn_c_try_link
 
+# ac_fn_c_check_func LINENO FUNC VAR
+# ----------------------------------
+# Tests whether FUNC exists, setting the cache variable VAR accordingly
+ac_fn_c_check_func ()
+{
+  as_lineno=${as_lineno-"$1"} as_lineno_stack=as_lineno_stack=$as_lineno_stack
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for $2" >&5
+$as_echo_n "checking for $2... " >&6; }
+if eval \${$3+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+/* Define $2 to an innocuous variant, in case <limits.h> declares $2.
+   For example, HP-UX 11i <limits.h> declares gettimeofday.  */
+#define $2 innocuous_$2
+
+/* System header to define __stub macros and hopefully few prototypes,
+    which can conflict with char $2 (); below.
+    Prefer <limits.h> to <assert.h> if __STDC__ is defined, since
+    <limits.h> exists even on freestanding compilers.  */
+
+#ifdef __STDC__
+# include <limits.h>
+#else
+# include <assert.h>
+#endif
+
+#undef $2
+
+/* Override any GCC internal prototype to avoid an error.
+   Use char because int might match the return type of a GCC
+   builtin and then its argument prototype would still apply.  */
+#ifdef __cplusplus
+extern "C"
+#endif
+char $2 ();
+/* The GNU C library defines this for functions which it implements
+    to always fail with ENOSYS.  Some functions are actually named
+    something starting with __ and the normal name is an alias.  */
+#if defined __stub_$2 || defined __stub___$2
+choke me
+#endif
+
+int
+main ()
+{
+return $2 ();
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  eval "$3=yes"
+else
+  eval "$3=no"
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+fi
+eval ac_res=\$$3
+	       { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_res" >&5
+$as_echo "$ac_res" >&6; }
+  eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno
+
+} # ac_fn_c_check_func
+
 # ac_fn_c_try_cpp LINENO
 # ----------------------
 # Try to preprocess conftest.$ac_ext, and return whether this succeeded.
@@ -4039,6 +4106,23 @@ $as_echo "yes" >&6; }
   HAVE_KRB5=1
   KRB5_LIBS=`$KRB5_CONFIG --libs`
   KRB5_FLAGS=`$KRB5_CONFIG --cflags`
+
+  SAVE_CFLAGS=$CFLAGS
+  SAVE_LIBS=$LIBS
+  CFLAGS="$CFLAGS $KRB5_FLAGS"
+  LIBS="$LIBS $KRB5_LIBS"
+
+  for ac_func in krb5_principal_get_realm
+do :
+  ac_fn_c_check_func "$LINENO" "krb5_principal_get_realm" "ac_cv_func_krb5_principal_get_realm"
+if test "x$ac_cv_func_krb5_principal_get_realm" = xyes; then :
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_KRB5_PRINCIPAL_GET_REALM 1
+_ACEOF
+
+fi
+done
+
 fi
 
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing versionsort" >&5
diff --git a/include/config.h.in b/include/config.h.in
index a2a05a8..8a52080 100644
--- a/include/config.h.in
+++ b/include/config.h.in
@@ -24,6 +24,9 @@
 /* Define to 1 if you have the <inttypes.h> header file. */
 #undef HAVE_INTTYPES_H
 
+/* Define to 1 if you have the `krb5_principal_get_realm' function. */
+#undef HAVE_KRB5_PRINCIPAL_GET_REALM
+
 /* Define to 1 if you have the `ldap_create_page_control' function. */
 #undef HAVE_LDAP_CREATE_PAGE_CONTROL
 
diff --git a/modules/cyrus-sasl.c b/modules/cyrus-sasl.c
index 68f9242..b9c16f3 100644
--- a/modules/cyrus-sasl.c
+++ b/modules/cyrus-sasl.c
@@ -64,6 +64,35 @@
 #endif
 #endif
 
+#ifdef HAVE_KRB5_PRINCIPAL_GET_REALM
+void _krb5_princ_realm(krb5_context context, krb5_const_principal princ,
+                          const char **realm, int *len)
+{
+	*realm = krb5_principal_get_realm(context, princ);
+	if (*realm)
+		*len = strlen(*realm);
+	else
+		*len = 0;
+	return;
+#else
+void _krb5_princ_realm(krb5_context context, krb5_const_principal princ,
+                          const char **realm, int *len)
+{
+	const krb5_data *data;
+
+	data = krb5_princ_realm(context, princ);
+	if (data) {
+		*realm = data->data;
+		*len = data->length;
+	} else {
+		*realm = NULL;
+		*len = 0;
+	}
+	return;
+}
+#endif
+
+
 /*
  *  Once a krb5 credentials cache is setup, we need to set the KRB5CCNAME
  *  environment variable so that the library knows where to find it.
@@ -379,7 +408,8 @@ sasl_do_kinit(unsigned logopt, struct lookup_context *ctxt)
 	krb5_principal tgs_princ, krb5_client_princ;
 	krb5_creds my_creds;
 	char *tgs_name;
-	int status;
+	const char *realm_name;
+	int status, realm_length;
 
 	if (ctxt->kinit_done)
 		return 0;
@@ -450,12 +480,11 @@ sasl_do_kinit(unsigned logopt, struct lookup_context *ctxt)
 	}
 
 	/* setup a principal for the ticket granting service */
+	_krb5_princ_realm(ctxt->krb5ctxt, krb5_client_princ, &realm_name, &realm_length);
 	ret = krb5_build_principal_ext(ctxt->krb5ctxt, &tgs_princ,
-		krb5_princ_realm(ctxt->krb5ctxt, krb5_client_princ)->length,
-		krb5_princ_realm(ctxt->krb5ctxt, krb5_client_princ)->data,
+		realm_length, realm_name,
 		strlen(KRB5_TGS_NAME), KRB5_TGS_NAME,
-		krb5_princ_realm(ctxt->krb5ctxt, krb5_client_princ)->length,
-		krb5_princ_realm(ctxt->krb5ctxt, krb5_client_princ)->data,
+		realm_length, realm_name,
 		0);
 	if (ret) {
 		error(logopt,