autopickup exception priority in pull request 226

The pull request #226 commentary follows:

One major limitation of the autopickup exception system is that you can't
define an exception from an exception, despite both menucolors and msgtypes
prioritizing rules based on the order they are defined in .nethackrc. This
is because the "always pickup" and "never pickup" exceptions are tracked in
different lists, and at runtime, when the player steps over an object, the
game checks these lists seperately, with "never pickup" taking precedence.
This means that if you want to pick up some but not all items matching a
given expression, you may need to write a long and kludgy list of regexes
to get the behavior you want.

I've edited the autopickup exception code to remove this necessity: now
the exceptions are stored in one list, and conflicts between them are
resolved based on their relative position in that list. Whether an
exception was inclusive or exclusive was already tracked individually;
I don't know why they were stored separately in the first place. This
edit makes the system both more convenient and more consistent with the
semantics of menucolors and msgtypes.

With these changes, the 33 autopickup exception rules in the wiki article
linked above may be replaced with the following 7 much simpler rules for
the exact same effect:

AUTOPICKUP_EXCEPTION=">.* corpse.*"
AUTOPICKUP_EXCEPTION="<.* newt corpse.*"
AUTOPICKUP_EXCEPTION="<.* lichen corpse.*"
AUTOPICKUP_EXCEPTION="<.* lizard corpse.*"
AUTOPICKUP_EXCEPTION="<.* floating eye corpse.*"
AUTOPICKUP_EXCEPTION="<.* wraith corpse.*
AUTOPICKUP_EXCEPTION=">.*\>.*"

closes #226

doc/fixes36.3

@@ -314,6 +314,7 @@ NetHack Community Patches (or Variation) Included
 -------------------------------------------------
 add a couple of engraving suggestions in pull request #79
 chasonr's faster method to write characters to msdos VGA in pull request #220
+autopickup exception priority change in pull request #226
 
 
 Code Cleanup and Reorganization

include/decl.h

@@ -418,6 +418,7 @@ struct autopickup_exception {
     boolean grab;
     struct autopickup_exception *next;
 };
+E struct autopickup_exception *apelist;
 
 struct plinemsg_type {
     xchar msgtype;  /* one of MSGTYP_foo */

include/flag.h

@@ -423,7 +423,6 @@ struct instance_flags {
     int wc2_statuslines;        /* default = 2, curses can handle 3 */
     int wc2_windowborders;	/* display borders on NetHack windows */
     int wc2_petattr;            /* text attributes for pet */
-    struct autopickup_exception *autopickup_exceptions;
 #ifdef WIN32
 #define MAX_ALTKEYHANDLER 25
     char altkeyhandler[MAX_ALTKEYHANDLER];

src/cmd.c

@@ -2139,7 +2139,7 @@ int final;
                 *ocl ? "'" : "", *ocl ? ocl : "all types", *ocl ? "'" : "");
         if (flags.pickup_thrown && *ocl) /* *ocl: don't show if 'all types' */
             Strcat(buf, " plus thrown");
-        if (iflags.autopickup_exceptions)
+        if (apelist)
             Strcat(buf, ", with exceptions");
     } else
         Strcpy(buf, "off");

src/decl.c

@@ -213,6 +213,8 @@ char preferred_pet; /* '\0', 'c', 'd', 'n' (none) */
 NEARDATA struct monst *mydogs = (struct monst *) 0;
 /* monsters that are moving to another dungeon level */
 NEARDATA struct monst *migrating_mons = (struct monst *) 0;
+NEARDATA struct autopickup_exception *apelist =
+                            (struct autopickup_exception *)0;
 
 NEARDATA struct mvitals mvitals[NUMMONS];
 NEARDATA long domove_attempting = 0L;

src/options.c

@@ -4414,7 +4414,7 @@ int
 count_apes(VOID_ARGS)
 {
     int numapes = 0;
-    struct autopickup_exception *ape = iflags.autopickup_exceptions;
+    struct autopickup_exception *ape = apelist;
 
     while (ape) {
       numapes++;
@@ -5327,7 +5327,7 @@ boolean setinitial, setfromfile;
             start_menu(tmpwin);
             if (numapes) {
                 ape = (struct autopickup_exception *)
-                    iflags.autopickup_exceptions;
+                    apelist;
                 any = zeroany;
                 add_menu(tmpwin, NO_GLYPH, &any, 0, 0, iflags.menu_headings,
                          "Always pickup '<'; never pickup '>'",
@@ -5897,7 +5897,7 @@ dotogglepickup()
     if (flags.pickup) {
         oc_to_str(flags.pickup_types, ocl);
         Sprintf(buf, "ON, for %s objects%s", ocl[0] ? ocl : "all",
-                (iflags.autopickup_exceptions)
+                (apelist)
                     ? ((count_apes() == 1)
                            ? ", with one exception"
                            : ", with some exceptions")
@@ -5952,8 +5952,8 @@ const char *mapping;
 
     ape->pattern = dupstr(text);
     ape->grab = grab;
-    ape->next = (struct autopickup_exception *) iflags.autopickup_exceptions;
+    ape->next = (struct autopickup_exception *) apelist;
-    iflags.autopickup_exceptions = (struct autopickup_exception *) ape;
+    apelist = (struct autopickup_exception *) ape;
     return 1;
 }
 
@@ -5963,14 +5963,14 @@ struct autopickup_exception *whichape;
 {
     struct autopickup_exception *ape, *freeape, *prev = 0;
 
-    for (ape = iflags.autopickup_exceptions; ape;) {
+    for (ape = apelist; ape;) {
         if (ape == whichape) {
             freeape = ape;
             ape = ape->next;
             if (prev)
                 prev->next = ape;
             else
-                iflags.autopickup_exceptions = ape;
+                apelist = ape;
             regex_free(freeape->regex);
             free((genericptr_t) freeape->pattern);
             free((genericptr_t) freeape);
@@ -5984,11 +5984,11 @@ struct autopickup_exception *whichape;
 void
 free_autopickup_exceptions()
 {
-    struct autopickup_exception *ape = iflags.autopickup_exceptions;
+    struct autopickup_exception *ape = apelist;
-    while ((ape = iflags.autopickup_exceptions) != 0) {
+    while ((ape = apelist) != 0) {
       regex_free(ape->regex);
       free((genericptr_t) ape->pattern);
-      iflags.autopickup_exceptions = ape->next;
+      apelist = ape->next;
       free((genericptr_t) ape);
     }
 }

src/pickup.c

@@ -718,11 +718,13 @@ struct obj *obj;
     /*
      *  Does the text description of this match an exception?
      */
-    struct autopickup_exception
+    struct autopickup_exception *ape = apelist;
-        *ape = iflags.autopickup_exceptions;
+
     if (ape) {
         char *objdesc = makesingular(doname(obj));
-        while (ape && !regex_match(objdesc, ape->regex)) ape = ape->next;
+
+        while (ape && !regex_match(objdesc, ape->regex))
+            ape = ape->next;
     }
     return ape;
 }
@@ -732,6 +734,7 @@ autopick_testobj(otmp, calc_costly)
 struct obj *otmp;
 boolean calc_costly;
 {
+    struct autopickup_exception *ape;
     static boolean costly = FALSE;
     const char *otypes = flags.pickup_types;
     boolean pickit;
@@ -748,9 +751,8 @@ boolean calc_costly;
     /* check for pickup_types */
     pickit = (!*otypes || index(otypes, otmp->oclass));
 
-    /* check for autopickup excpetions */
+    /* check for autopickup exceptions */
-    struct autopickup_exception
+    ape = check_autopickup_exceptions(otmp);
-        *ape = check_autopickup_exceptions(otmp);
     if (ape)
         pickit = ape->grab;