Low: build: define constant for log directory

This defines CRM_LOG_DIR for (by default) /var/log/pacemaker. This will be used
as the location for container logs, and (when we are ready to make a
significant user-visible change) eventually for the main pacemaker log.

Author: kgaillot

configure.ac

@@ -1076,6 +1076,10 @@ CRM_STATE_DIR=${localstatedir}/run/crm
 AC_DEFINE_UNQUOTED(CRM_STATE_DIR,"$CRM_STATE_DIR", Where to keep state files and sockets)
 AC_SUBST(CRM_STATE_DIR)
 
+CRM_LOG_DIR="${localstatedir}/log/pacemaker"
+AC_DEFINE_UNQUOTED(CRM_LOG_DIR,"$CRM_LOG_DIR", Where Pacemaker can store log files)
+AC_SUBST(CRM_LOG_DIR)
+
 CRM_PACEMAKER_DIR=${localstatedir}/lib/pacemaker
 AC_DEFINE_UNQUOTED(CRM_PACEMAKER_DIR,"$CRM_PACEMAKER_DIR", Location to store directory produced by Pacemaker daemons)
 AC_SUBST(CRM_PACEMAKER_DIR)

include/crm_config.h.in

@@ -43,6 +43,9 @@
 
 /****** Directories ******/
 
+/* Where Pacemaker can store log files */
+#undef CRM_LOG_DIR
+
 /* Location for Pacemaker daemons */
 #undef CRM_DAEMON_DIR
 

lib/common/logging.c

@@ -223,6 +223,10 @@ crm_add_logfile(const char *filename)
     bool is_default = false;
     static int default_fd = -1;
     static gboolean have_logfile = FALSE;
+
+    /* @COMPAT This should be CRM_LOG_DIR "/pacemaker.log". We aren't changing
+     * it yet because it will be a significant user-visible change to publicize.
+     */
     const char *default_logfile = "/var/log/pacemaker.log";
 
     struct stat parent;

mcp/corosync.c

@@ -394,6 +394,13 @@ mcp_read_config(void)
         free(debug_enabled);
     }
 
+    /* If the user didn't explicitly configure a Pacemaker log file, check
+     * whether they configured a heartbeat or corosync log file, and use that.
+     *
+     * @COMPAT This should all go away, and we should just rely on the logging
+     * set up by crm_log_init(). We aren't doing this yet because it is a
+     * significant user-visible change that will need to be publicized.
+     */
     const_value = daemon_option("debugfile");
     if (daemon_option("logfile")) {
         /* File logging is already setup by crm_log_init() */