Support a per-vhost nice value.

Index: apache2.2/server/mpm/experimental/itk/itk.c
===================================================================
--- apache2.2.orig/server/mpm/experimental/itk/itk.c
+++ apache2.2/server/mpm/experimental/itk/itk.c
@@ -161,6 +161,7 @@ typedef struct
 	gid_t gid;
 	char *username;
 	int max_clients_vhost;
+	int nice_value;
 } itk_server_conf;
 
 module AP_MODULE_DECLARE_DATA mpm_itk_module;
@@ -507,7 +508,8 @@ static void child_main(int child_num_arg
     cap_t caps;
     cap_value_t suidcaps[] = {
         CAP_SETUID,
-        CAP_SETGID
+        CAP_SETGID,
+        CAP_SYS_NICE
     };
 #endif    
 
@@ -1442,6 +1444,11 @@ static int itk_post_read(request_rec *r)
     strncpy(ap_scoreboard_image->servers[my_child_num][0].vhost, r->server->server_hostname, 31);
     ap_scoreboard_image->servers[my_child_num][0].vhost[31] = 0;
 
+    if (setpriority(PRIO_PROCESS, 0, sconf->nice_value)) {
+        _DBG("setpriority(): %s", strerror(errno));
+        err = 1;
+    }
+
     wanted_uid = sconf->uid;
     wanted_gid = sconf->gid;
     wanted_username = sconf->username;
@@ -1452,7 +1459,7 @@ static int itk_post_read(request_rec *r)
         wanted_username = unixd_config.user_name;
     }
 
-    if (wanted_uid != -1 && wanted_gid != -1 && (getuid() != wanted_uid || getgid() != wanted_gid)) {
+    if (!err && wanted_uid != -1 && wanted_gid != -1 && (getuid() != wanted_uid || getgid() != wanted_gid)) {
         if (setgid(wanted_gid)) {
             _DBG("setgid(): %s", strerror(errno));
             err = 1;
@@ -1472,7 +1479,7 @@ static int itk_post_read(request_rec *r)
      */
     if (err) {
         ap_log_error(APLOG_MARK, APLOG_WARNING, 0, NULL, \
-            "Couldn't set uid/gid, closing connection.");
+            "Couldn't set uid/gid/priority, closing connection.");
         ap_lingering_close(r->connection);
         exit(0);
     }
@@ -1629,6 +1636,28 @@ static const char *set_max_clients_vhost
     return NULL;
 }  
 
+static const char *set_nice_value (cmd_parms *cmd, void *dummy, const char *arg)
+{
+    itk_server_conf *sconf =
+        (itk_server_conf *) ap_get_module_config(cmd->server->module_config, &mpm_itk_module);
+    int nice_value = atoi(arg);
+
+    if (nice_value < -20) {
+        ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+                     "WARNING: NiceValue of %d is below -20, increasing NiceValue to -20.",
+                     nice_value);
+        nice_value = -20;
+    }
+    else if (nice_value > 19) {
+        ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL,
+                     "WARNING: NiceValue of %d is above 19, lowering NiceValue to 19.",
+                     nice_value);
+        nice_value = 19;
+    }
+    sconf->nice_value = nice_value;
+    return NULL;
+}
+
 static const command_rec itk_cmds[] = {
 UNIX_DAEMON_COMMANDS,
 LISTEN_COMMANDS,
@@ -1646,6 +1675,8 @@ AP_INIT_TAKE2("AssignUserID", assign_use
               "Tie a virtual host to a specific child process."),
 AP_INIT_TAKE1("MaxClientsVHost", set_max_clients_vhost, NULL, RSRC_CONF,
               "Maximum number of children alive at the same time for this virtual host."),
+AP_INIT_TAKE1("NiceValue", set_nice_value, NULL, RSRC_CONF,
+              "Set nice value for the given vhost, from -20 (highest priority) to 19 (lowest priority)."),
 AP_GRACEFUL_SHUTDOWN_TIMEOUT_COMMAND,
 { NULL }
 };
@@ -1657,6 +1688,7 @@ static void *itk_create_config(apr_pool_
         apr_pcalloc(p, sizeof(itk_server_conf));
     c->uid = c->gid = -1;
     c->max_clients_vhost = -1;
+    c->nice_value = 0;
     return c;
 }