doom: Refactor IWAD dehacked patch loading.

As per suggestions from Fabian Greffrath:
 * Change -noiwaddeh to -nodeh for consistency with other source ports
   (Boom-derived source ports use this to disable loading of DEHACKED
   lumps).
 * Extend the parameter so that it also disables loading of the Chex
   Quest dehacked patch.
 * Refactor the code for loading IWAD dehacked patches to all be in a
   single function.

1 files changed, 56 insertions, 59 deletions

diff --git a/src/doom/d_main.c b/src/doom/d_main.c
index 15134d7a..ef8e8aea 100644
--- a/src/doom/d_main.c
+++ b/src/doom/d_main.c
@@ -986,17 +986,57 @@ void PrintGameVersion(void)
     }
 }
 
-// Load the Chex Quest dehacked file, if we are in Chex mode.
+// Function called at exit to display the ENDOOM screen
 
-static void LoadChexDeh(void)
+static void D_Endoom(void)
 {
-    char *chex_deh = NULL;
-    char *sep;
+    byte *endoom;
+
+    // Don't show ENDOOM if we have it disabled, or we're running
+    // in screensaver or control test mode. Only show it once the
+    // game has actually started.
+
+    if (!show_endoom || !main_loop_started
+     || screensaver_mode || M_CheckParm("-testcontrols") > 0)
+    {
+        return;
+    }
+
+    endoom = W_CacheLumpName(DEH_String("ENDOOM"), PU_STATIC);
+
+    I_Endoom(endoom);
+}
+
+// Load dehacked patches needed for certain IWADs.
+static void LoadIwadDeh(void)
+{
+    // The Freedoom IWADs have DEHACKED lumps that must be loaded.
+    if (W_CheckNumForName("FREEDOOM") >= 0)
+    {
+        // Old versions of Freedoom (before 2014-09) did not have technically
+        // valid DEHACKED lumps, so ignore errors and just continue if this
+        // is an old IWAD.
+        DEH_LoadLumpByName("DEHACKED", false, true);
+    }
 
+    // If this is the HACX IWAD, we need to load the DEHACKED lump.
+    if (gameversion == exe_hacx)
+    {
+        if (!DEH_LoadLumpByName("DEHACKED", true, false))
+        {
+            I_Error("DEHACKED lump not found.  Please check that this is the "
+                    "Hacx v1.2 IWAD.");
+        }
+    }
+
+    // Chex Quest needs a separate Dehacked patch which must be downloaded
+    // and installed next to the IWAD.
     if (gameversion == exe_chex)
     {
-        // Look for chex.deh in the same directory as the IWAD file.
+        char *chex_deh = NULL;
+        char *sep;
 
+        // Look for chex.deh in the same directory as the IWAD file.
         sep = strrchr(iwadfile, DIR_SEPARATOR);
 
         if (sep != NULL)
@@ -1014,7 +1054,6 @@ static void LoadChexDeh(void)
 
         // If the dehacked patch isn't found, try searching the WAD
         // search path instead.  We might find it...
-
         if (!M_FileExists(chex_deh))
         {
             free(chex_deh);
@@ -1022,7 +1061,6 @@ static void LoadChexDeh(void)
         }
 
         // Still not found?
-
         if (chex_deh == NULL)
         {
             I_Error("Unable to find Chex Quest dehacked file (chex.deh).\n"
@@ -1039,42 +1077,6 @@ static void LoadChexDeh(void)
     }
 }
 
-// Function called at exit to display the ENDOOM screen
-
-static void D_Endoom(void)
-{
-    byte *endoom;
-
-    // Don't show ENDOOM if we have it disabled, or we're running
-    // in screensaver or control test mode. Only show it once the
-    // game has actually started.
-
-    if (!show_endoom || !main_loop_started
-     || screensaver_mode || M_CheckParm("-testcontrols") > 0)
-    {
-        return;
-    }
-
-    endoom = W_CacheLumpName(DEH_String("ENDOOM"), PU_STATIC);
-
-    I_Endoom(endoom);
-}
-
-static void LoadHacxDeh(void)
-{
-    // If this is the HACX IWAD, we need to load the DEHACKED lump.
-
-    if (gameversion == exe_hacx)
-    {
-        if (!M_ParmExists("-noiwaddeh")
-         && !DEH_LoadLumpByName("DEHACKED", true, false))
-        {
-            I_Error("DEHACKED lump not found.  Please check that this is the "
-                    "Hacx v1.2 IWAD.");
-        }
-    }
-}
-
 //
 // D_DoomMain
 //
@@ -1300,23 +1302,22 @@ void D_DoomMain (void)
 
     W_CheckCorrectIWAD(doom);
 
-    // The Freedoom IWADs have DEHACKED lumps with cosmetic changes to the
-    // in-game messages. Load this, but allow it to be disabled on the
-    // command line if desired.
+    // Now that we've loaded the IWAD, we can figure out what gamemission
+    // we're playing and which version of Vanilla Doom we need to emulate.
+    D_IdentifyVersion();
+    InitGameVersion();
 
     //!
     // @category mod
     //
-    // Disable automatic loading of Dehacked patches contained in some
+    // Disable automatic loading of Dehacked patches for certain
     // IWAD files.
-
-    if (!M_ParmExists("-noiwaddeh")
-     && W_CheckNumForName("FREEDOOM") >= 0)
+    //
+    if (!M_ParmExists("-nodeh"))
     {
-        // Old versions of Freedoom (before 2014-09) did not have technically
-        // valid DEHACKED lumps, so ignore errors and just continue if this
-        // is an old IWAD.
-        DEH_LoadLumpByName("DEHACKED", false, true);
+        // Some IWADs have dehacked patches that need to be loaded for
+        // them to be played properly.
+        LoadIwadDeh();
     }
 
     // Doom 3: BFG Edition includes modified versions of the classic
@@ -1407,11 +1408,7 @@ void D_DoomMain (void)
     // Generate the WAD hash table.  Speed things up a bit.
 
     W_GenerateHashTable();
-    
-    D_IdentifyVersion();
-    InitGameVersion();
-    LoadChexDeh();
-    LoadHacxDeh();
+
     D_SetGameDescription();
     savegamedir = M_GetSaveGameDir(D_SaveGameIWADName(gamemission));