options key parsing

OPTIONS=menu_previous_page:\mv
  BINDINGS=M-v:menu_previous_page
both worked, but
  OPTIONS=menu_previous_page:M-v
  BINDINGS=\mv:menu_previous_page
both failed.  Make all four variations work.  Tiny change made large
by the need to move some things around.

The option definition for menu_first_page had a couple of its flag
bits swapped.  I didn't try to figure out whether that had any impact.

src/cmd.c

@@ -6,25 +6,6 @@
 #include "hack.h"
 #include "func_tab.h"
 
-/* Macros for meta and ctrl modifiers:
- *   M and C return the meta/ctrl code for the given character;
- *     e.g., (C('c') is ctrl-c
- */
-#ifndef M
-#ifndef NHSTDC
-#define M(c) (0x80 | (c))
-#else
-#define M(c) ((c) - 128)
-#endif /* NHSTDC */
-#endif
-
-#ifndef C
-#define C(c) (0x1f & (c))
-#endif
-
-#define unctrl(c) ((c) <= C('z') ? (0x60 | (c)) : (c))
-#define unmeta(c) (0x7f & (c))
-
 #ifdef ALTMETA
 static boolean alt_esc = FALSE;
 #endif
@@ -3045,96 +3026,6 @@ spkey_name(int nhkf)
     return name;
 }
 
-/* returns a one-byte character from the text; may change txt[] */
-uchar
-txt2key(char *txt)
-{
-    uchar uc;
-    boolean makemeta = FALSE;
-
-    txt = trimspaces(txt);
-    if (!*txt)
-        return '\0';
-
-    /* simple character */
-    if (!txt[1])
-        return (uchar) txt[0];
-
-    /* a few special entries */
-    if (!strcmp(txt, "<enter>"))
-        return '\n';
-    if (!strcmp(txt, "<space>"))
-        return ' ';
-    if (!strcmp(txt, "<esc>"))
-        return '\033';
-
-    /* control and meta keys */
-    if (highc(*txt) == 'M') {
-        /*
-         * M <nothing>             return 'M'
-         * M - <nothing>           return M-'-'
-         * M <other><nothing>      return M-<other>
-         * otherwise M is pending until after ^/C- processing.
-         * Since trailing spaces are discarded, the only way to
-         * specify M-' ' is via "160".
-         */
-        if (!txt[1])
-            return (uchar) *txt;
-        /* skip past 'M' or 'm' and maybe '-' */
-        ++txt;
-        if (*txt == '-' && txt[1])
-            ++txt;
-        if (!txt[1])
-            return M((uchar) *txt);
-        makemeta = TRUE;
-    }
-    if (*txt == '^' || highc(*txt) == 'C') {
-        /*
-         * C <nothing>             return 'C' or M-'C'
-         * C - <nothing>           return '-' or M-'-'
-         * C [-] <other><nothing>  return C-<other> or M-C-<other>
-         * C [-] ?                 return <rubout>
-         * otherwise return C-<other> or M-C-<other>
-         */
-        uc = (uchar) *txt;
-        if (!txt[1])
-            return makemeta ? M(uc) : uc;
-        ++txt;
-        /* unlike M-x, lots of values of x are invalid for C-x;
-           checking and rejecting them is not worthwhile; GIGO;
-           we do accept "^-x" as synonym for "^x" or "C-x" */
-        if (*txt == '-' && txt[1])
-            ++txt;
-        /* and accept ^?, which gets used despite not being a control char */
-        if (*txt == '?')
-            return (uchar) (makemeta ? '\377' : '\177'); /* rubout/delete */
-        uc = C((uchar) *txt);
-        return makemeta ? M(uc) : uc;
-    }
-    if (makemeta && *txt)
-        return M((uchar) *txt);
-
-    /* FIXME: should accept single-quote single-character single-quote
-       and probably single-quote backslash octal-digits single-quote;
-       if we do that, the M- and C- results should be pending until
-       after, so that C-'X' becomes valid for ^X */
-
-    /* ascii codes: must be three-digit decimal */
-    if (*txt >= '0' && *txt <= '9') {
-        uchar key = 0;
-        int i;
-
-        for (i = 0; i < 3; i++) {
-            if (txt[i] < '0' || txt[i] > '9')
-                return '\0';
-            key = 10 * key + txt[i] - '0';
-        }
-        return key;
-    }
-
-    return '\0';
-}
-
 /* returns the text for a one-byte encoding;
  * must be shorter than a tab for proper formatting */
 char *