symset parsing

Add support for character enclosed within single quotes.  Single
character without quotes would work for most characters, but not
'#' and possibly not '^' or '\\'.  All the values in dat/symbols
are specified via backslash+digits so it isn't obvious that some
other form of value is allowed.

I think this parsing accepts all valid values.  It doesn't reject
all invalid ones:  opening quote followed by valid escape sequence
followed by junk followed by closing quote will ignore the junk.
I don't think there's any pressing need to worry about that.

doc/fixes36.1

@@ -280,6 +280,7 @@ REPRODUCIBLE_BUILD is new config.h setting to fetch build date+time from
 	environment instead of using current date+time, so that later rebuild
 	could duplicate the original (disabled by default; tested for Unix)
 default value for vibrating square symbol changed from yellow '^' to purple '~'
+allow symbol set values to be specified via char within single quotes
 
 
 Platform- and/or Interface-Specific New Features

include/extern.h

@@ -1,4 +1,4 @@
-/* NetHack 3.6	extern.h	$NHDT-Date: 1457570257 2016/03/10 00:37:37 $  $NHDT-Branch: NetHack-3.6.0 $:$NHDT-Revision: 1.552 $ */
+/* NetHack 3.6	extern.h	$NHDT-Date: 1459987582 2016/04/07 00:06:22 $  $NHDT-Branch: NetHack-3.6.0 $:$NHDT-Revision: 1.554 $ */
 /* Copyright (c) Steve Creps, 1988.				  */
 /* NetHack may be freely redistributed.  See license for details. */
 
@@ -1661,7 +1661,7 @@ E void NDECL(free_symsets);
 E boolean FDECL(parsesymbols, (char *));
 E struct symparse *FDECL(match_sym, (char *));
 E void NDECL(set_playmode);
-E int FDECL(sym_val, (char *));
+E int FDECL(sym_val, (const char *));
 E const char *FDECL(clr2colorname, (int));
 E int FDECL(match_str2clr, (char *));
 E boolean FDECL(add_menu_coloring, (char *));

src/files.c

@@ -1,4 +1,4 @@
-/* NetHack 3.6	files.c	$NHDT-Date: 1455835581 2016/02/18 22:46:21 $  $NHDT-Branch: NetHack-3.6.0 $:$NHDT-Revision: 1.204 $ */
+/* NetHack 3.6	files.c	$NHDT-Date: 1459987580 2016/04/07 00:06:20 $  $NHDT-Branch: NetHack-3.6.0 $:$NHDT-Revision: 1.205 $ */
 /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
 /* NetHack may be freely redistributed.  See license for details. */
 
@@ -2820,14 +2820,13 @@ int which_set;
     mungspaces(buf);
     if (!*buf || *buf == '#' || !strcmp(buf, " "))
         return 1;
-    /* remove trailing comment, if any */
+    /* remove trailing comment, if any (this isn't strictly needed for
-    if ((commentp = rindex(buf, '#')) != 0) {
+       individual symbols, and it won't matter if "X#comment" without
-        *commentp = '\0';
+       separating space slips through; for handling or set description,
-        /* remove space preceding the stripped comment, if any;
+       symbol set creator is responsible for preceding '#' with a space
-           we know 'commentp > buf' because *buf=='#' was caught above */
+       and that comment itself doesn't contain " #") */
-        if (commentp[-1] == ' ')
+    if ((commentp = rindex(buf, '#')) != 0 && commentp[-1] == ' ')
-            *--commentp = '\0';
+        commentp[-1] = '\0';
-    }
 
     /* find the '=' or ':' */
     bufp = index(buf, '=');

src/options.c

@@ -1,4 +1,4 @@
-/* NetHack 3.6	options.c	$NHDT-Date: 1455357588 2016/02/13 09:59:48 $  $NHDT-Branch: NetHack-3.6.0 $:$NHDT-Revision: 1.264 $ */
+/* NetHack 3.6	options.c	$NHDT-Date: 1459987581 2016/04/07 00:06:21 $  $NHDT-Branch: NetHack-3.6.0 $:$NHDT-Revision: 1.267 $ */
 /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
 /* NetHack may be freely redistributed.  See license for details. */
 
@@ -858,8 +858,8 @@ char *tp;
         } else if (*cp == '^') { /* expand control-character syntax */
             cval = (*++cp & 0x1f);
             ++cp;
-            /* remaining cases are all for backslash and we know cp[1] is not
+
-             * \0 */
+        /* remaining cases are all for backslash; we know cp[1] is not \0 */
         } else if (index(dec, cp[1])) {
             ++cp; /* move past backslash to first digit */
             do {
@@ -5218,11 +5218,41 @@ char *buf;
 
 int
 sym_val(strval)
-char *strval;
+const char *strval;
 {
     char buf[QBUFSZ];
+
     buf[0] = '\0';
-    escapes(strval, buf);
+    if (!strval[0] || !strval[1]) { /* empty, or single character */
+        /* if single char is space or tab, leave buf[0]=='\0' */
+        if (!isspace(strval[0]))
+            buf[0] = strval[0];
+    } else if (strval[0] == '\'') { /* single quote */
+        /* simple matching single quote; we know strval[1] isn't '\0' */
+        if (strval[2] == '\'' && !strval[3]) {
+            /* accepts '\' as backslash and ''' as single quote */
+            buf[0] = strval[1];
+
+        /* if backslash, handle single or double quote or second backslash */
+        } else if (strval[1] == '\\' && strval[2] && strval[3] == '\''
+            && index("'\"\\", strval[2]) && !strval[4]) {
+            buf[0] = strval[2];
+
+        /* not simple quote or basic backslash;
+           strip closing quote and let escapes() deal with it */
+        } else {
+            char *p, tmp[QBUFSZ];
+
+            (void) strncpy(tmp, strval + 1, sizeof tmp - 1);
+            tmp[sizeof tmp - 1] = '\0';
+            if ((p = rindex(tmp, '\'')) != 0) {
+                *p = '\0';
+                escapes(tmp, buf);
+            } /* else buf[0] stays '\0' */
+        }
+    } else /* not lone char nor single quote */
+        escapes(strval, buf);
+
     return (int) *buf;
 }