build pam test module as a part of the build

and install in mysql-test/suite/plugins/pam
so that it could be manually copied into /etc if needed

plugin/auth_pam/CMakeLists.txt

@@ -12,11 +12,16 @@ IF(HAVE_PAM_APPL_H)
   ADD_DEFINITIONS(-D_GNU_SOURCE)
   MYSQL_ADD_PLUGIN(auth_pam_v1 auth_pam_v1.c LINK_LIBRARIES pam MODULE_ONLY)
   MYSQL_ADD_PLUGIN(auth_pam auth_pam.c LINK_LIBRARIES pam dl MODULE_ONLY)
-  MYSQL_ADD_EXECUTABLE(auth_pam_tool auth_pam_tool.c DESTINATION ${INSTALL_PLUGINDIR}/auth_pam_tool_dir COMPONENT Server)
-  TARGET_LINK_LIBRARIES(auth_pam_tool pam)
-  INSTALL(CODE "EXECUTE_PROCESS(
-                   COMMAND chmod u=rwx,g=,o= auth_pam_tool_dir
-                   COMMAND chmod u=rwxs,g=rx,o=rx auth_pam_tool_dir/auth_pam_tool
-                   WORKING_DIRECTORY \$ENV{DESTDIR}\${CMAKE_INSTALL_PREFIX}/${INSTALL_PLUGINDIR}/)"
-                 COMPONENT Server)
+  IF (TARGET auth_pam)
+    MYSQL_ADD_EXECUTABLE(auth_pam_tool auth_pam_tool.c DESTINATION ${INSTALL_PLUGINDIR}/auth_pam_tool_dir COMPONENT Server)
+    TARGET_LINK_LIBRARIES(auth_pam_tool pam)
+    INSTALL(CODE "EXECUTE_PROCESS(
+                     COMMAND chmod u=rwx,g=,o= auth_pam_tool_dir
+                     COMMAND chmod u=rwxs,g=rx,o=rx auth_pam_tool_dir/auth_pam_tool
+                     WORKING_DIRECTORY \$ENV{DESTDIR}\${CMAKE_INSTALL_PREFIX}/${INSTALL_PLUGINDIR}/)"
+                   COMPONENT Server)
+  ENDIF()
+  IF(TARGET auth_pam OR TARGET auth_pam_v1)
+    ADD_SUBDIRECTORY(testing)
+  ENDIF()
 ENDIF(HAVE_PAM_APPL_H)

plugin/auth_pam/testing/CMakeLists.txt

+#  gcc pam_mariadb_mtr.c -shared -lpam -fPIC -o pam_mariadb_mtr.so
+
+ADD_LIBRARY(pam_mariadb_mtr MODULE pam_mariadb_mtr.c)
+SET_TARGET_PROPERTIES (pam_mariadb_mtr PROPERTIES PREFIX "")
+TARGET_LINK_LIBRARIES(pam_mariadb_mtr pam)
+
+SET(dest DESTINATION "${INSTALL_MYSQLTESTDIR}/suite/plugins/pam" COMPONENT Test)
+INSTALL(TARGETS pam_mariadb_mtr ${dest})
+INSTALL(FILES mariadb_mtr.conf RENAME mariadb_mtr ${dest})

plugin/auth_pam/testing/mariadb_mtr.conf

+# Put it in /etc/pam.d/mariadb_mtr
+
+auth            required        pam_mariadb_mtr.so pam_test
+account         required        pam_permit.so

plugin/auth_pam/testing/pam_mariadb_mtr.c

 /*
   This code is in the public domain and has no copyright.
 
-  Pam module to test pam authentication plugin. Used in pam.test.
+  Pam module to test pam authentication plugin. Used in pam tests.
   Linux only.
-
-  Compile as
   
-     gcc pam_mariadb_mtr.c -shared -lpam -fPIC -o pam_mariadb_mtr.so
-
   Install as appropriate (for example, in /lib/security/).
-  Create /etc/pam.d/mariadb_mtr with
-=========================================================
-auth            required        pam_mariadb_mtr.so pam_test
-account         required        pam_permit.so
-=========================================================
+  see also mariadb_mtr.conf
 */
 
 #include <stdlib.h>
@@ -59,7 +51,7 @@ int pam_sm_authenticate(pam_handle_t *pamh, int flags,
   if (strcmp(r1, "crash pam module") == 0 && atoi(r2) == 616)
     abort();
 
-  if (strlen(r1) == atoi(r2) % 100)
+  if (strlen(r1) == (uint)atoi(r2) % 100)
     retval = PAM_SUCCESS;
   else
     retval = PAM_AUTH_ERR;