factor V_CalcRefdef into two functions

[xonotic/darkplaces.git] / host.c

diff --git a/host.c b/host.c
index 729e998d2fa52652d8159b166629a280e8ff70c0..a8a8e0de767d63be34b39acf583f824f0e9aea70 100644 (file)
--- a/host.c
+++ b/host.c
@@ -85,6 +85,9 @@ cvar_t developer_entityparsing = {0, "developer_entityparsing", "0", "prints det
 cvar_t timestamps = {CVAR_SAVE, "timestamps", "0", "prints timestamps on console messages"};
 cvar_t timeformat = {CVAR_SAVE, "timeformat", "[%Y-%m-%d %H:%M:%S] ", "time format to use on timestamped console messages"};
 
+cvar_t sessionid = {CVAR_READONLY, "sessionid", "", "ID of the current session (use the -sessionid parameter to set it); this is always either empty or begins with a dot (.)"};
+cvar_t locksession = {0, "locksession", "0", "Lock the session? 0 = no, 1 = yes and abort on failure, 2 = yes and continue on failure"};
+
 /*
 ================
 Host_AbortCurrentFrame
@@ -1071,6 +1074,63 @@ qboolean sys_nostdout = false;
 
 extern qboolean host_stuffcmdsrun;
 
+static qfile_t *locksession_fh = NULL;
+static qboolean locksession_run = false;
+static void Host_InitSession(void)
+{
+       int i;
+       Cvar_RegisterVariable(&sessionid);
+       Cvar_RegisterVariable(&locksession);
+
+       // load the session ID into the read-only cvar
+       if ((i = COM_CheckParm("-sessionid")) && (i + 1 < com_argc))
+       {
+               char vabuf[1024];
+               if(com_argv[i+1][0] == '.')
+                       Cvar_SetQuick(&sessionid, com_argv[i+1]);
+               else
+                       Cvar_SetQuick(&sessionid, va(vabuf, sizeof(vabuf), ".%s", com_argv[i+1]));
+       }
+}
+void Host_LockSession(void)
+{
+       if(locksession_run)
+               return;
+       locksession_run = true;
+       if(locksession.integer != 0)
+       {
+               char vabuf[1024];
+               locksession_fh = FS_SysOpen(va(vabuf, sizeof(vabuf), "%slock%s", *fs_userdir ? fs_userdir : fs_basedir, sessionid.string), "wl", false);
+               // TODO maybe write the pid into the lockfile, while we are at it? may help server management tools
+               if(!locksession_fh)
+               {
+                       if(locksession.integer == 2)
+                       {
+                               Con_Printf("WARNING: session lock %slock%s could not be acquired. Please run with -sessionid and an unique session name. Continuing anyway.\n", *fs_userdir ? fs_userdir : fs_basedir, sessionid.string);
+                       }
+                       else
+                       {
+                               Sys_Error("session lock %slock%s could not be acquired. Please run with -sessionid and an unique session name.\n", *fs_userdir ? fs_userdir : fs_basedir, sessionid.string);
+                       }
+               }
+       }
+}
+void Host_UnlockSession(void)
+{
+       if(!locksession_run)
+               return;
+       locksession_run = false;
+
+       if(locksession_fh)
+       {
+               FS_Close(locksession_fh);
+               // NOTE: we can NOT unlink the lock here, as doing so would
+               // create a race condition if another process created it
+               // between our close and our unlink
+               locksession_fh = NULL;
+       }
+}
+
 /*
 ====================
 Host_Init
@@ -1168,6 +1228,9 @@ static void Host_Init (void)
        // initialize filesystem (including fs_basedir, fs_gamedir, -game, scr_screenshot_name)
        FS_Init();
 
+       // register the cvars for session locking
+       Host_InitSession();
+
        // must be after FS_Init
        Crypto_Init();
        Crypto_Init_Commands();
@@ -1356,7 +1419,10 @@ void Host_Shutdown(void)
        Sys_Shutdown();
        Log_Close();
        Crypto_Shutdown();
-       FS_Shutdown();
+
+       Host_UnlockSession();
+
+       S_Shutdown();
        Con_Shutdown();
        Memory_Shutdown();
 }