From: nobu.nokada@...
Date: 2005-05-12T09:21:31+09:00
Subject: Re: Encoding Pragma

Hi,

At Thu, 12 May 2005 08:03:48 +0900,
Bertram Scharpf wrote in [ruby-core:04881]:
> Why don't I retrieve the UTF-8 answer in the first case?

Although ruby doesn't have pragma right now, I'm using this
patch.


Index: intern.h
===================================================================
RCS file: /cvs/ruby/src/ruby/intern.h,v
retrieving revision 1.166
diff -U2 -p -r1.166 intern.h
--- intern.h	19 Apr 2005 14:02:48 -0000	1.166
+++ intern.h	19 Apr 2005 15:42:23 -0000
@@ -395,4 +395,5 @@ void ruby_load_script _((void));
 void ruby_init_loadpath _((void));
 void ruby_incpush _((const char*));
+void ruby_modeset _((const char*, int));
 /* signal.c */
 VALUE rb_f_kill _((int, VALUE*));
Index: parse.y
===================================================================
RCS file: /cvs/ruby/src/ruby/parse.y,v
retrieving revision 1.378
diff -U2 -p -r1.378 parse.y
--- parse.y	1 May 2005 00:15:25 -0000	1.378
+++ parse.y	1 May 2005 00:59:20 -0000
@@ -4445,4 +4445,5 @@ yycompile(parser, f, line)
     NODE *node = 0;
     struct RVarmap *vp, *vars = ruby_dyna_vars;
+    const char *kcode_save;
 
     if (!compile_for_eval && rb_safe_level() == 0 &&
@@ -4468,4 +4469,5 @@ yycompile(parser, f, line)
     }
 
+    kcode_save = rb_get_kcode();
     ruby_current_node = 0;
     ruby_sourcefile = rb_source_filename(f);
@@ -4474,4 +4476,5 @@ yycompile(parser, f, line)
     ruby_debug_lines = 0;
     compile_for_eval = 0;
+    rb_set_kcode(kcode_save);
 
     vp = ruby_dyna_vars;
@@ -5404,14 +5407,11 @@ parser_yylex(parser)
 
       case '#':		/* it's a comment */
-	while ((c = nextc()) != '\n') {
-	    if (c == -1) {
-#ifdef RIPPER
-                ripper_dispatch_scan_event(parser, tCOMMENT);
-#endif
-		return 0;
-            }
+	if (lex_p < lex_pend) {
+	    ruby_modeset(lex_p, lex_pend - lex_p);
+	    lex_p = lex_pend;
 	}
 #ifdef RIPPER
         ripper_dispatch_scan_event(parser, tCOMMENT);
+        if (lex_p[-1] != '\n') return 0;
         fallthru = Qtrue;
 #endif
Index: ruby.c
===================================================================
RCS file: /cvs/ruby/src/ruby/ruby.c,v
retrieving revision 1.100
diff -U2 -p -r1.100 ruby.c
--- ruby.c	1 May 2005 00:13:34 -0000	1.100
+++ ruby.c	1 May 2005 00:59:20 -0000
@@ -401,4 +401,127 @@ require_libraries()
 }
 
+/* emacsen -*- hack */
+typedef void (*rb_modeset_setter_t) _((const char *val, const char *name));
+
+struct modeset {
+    const char *name;
+    rb_modeset_setter_t func;
+};
+
+static const struct modeset modesets[] = {
+    {"coding", (rb_modeset_setter_t)rb_set_kcode},
+};
+
+static const char *
+modeset_marker(str, len)
+    const char *str;
+    int len;
+{
+    int i = 2;
+
+    while (i < len) {
+	switch (str[i]) {
+	  case '-':
+	    if (str[i-1] == '*' && str[i-2] == '-') {
+		return str + i + 1;
+	    }
+	    i += 2;
+	    break;
+	  case '*':
+	    if (i + 1 >= len) return 0;
+	    if (str[i+1] != '-') {
+		i += 4;
+	    }
+	    else if (str[i-1] != '-') {
+		i += 2;
+	    }
+	    else {
+		return str + i + 2;
+	    }
+	    break;
+	  default:
+	    i += 3;
+	    break;
+	}
+    }
+    return 0;
+}
+
+void
+ruby_modeset(str, len)
+    const char *str;
+    int len;
+{
+    VALUE name = 0, val = 0;
+    const char *beg, *end, *vbeg, *vend;
+#define str_copy(_s, _p, _n) ((_s) \
+	? (rb_str_resize((_s), (_n)), \
+	   MEMCPY(RSTRING(_s)->ptr, (_p), char, (_n)), (_s)) \
+	: ((_s) = rb_str_new((_p), (_n))))
+
+    if (!(beg = modeset_marker(str, len))) return;
+    if (!(end = modeset_marker(beg, str + len - beg))) return;
+    str = beg;
+    len = end - beg - 3;
+    
+    /* %r"([^\\s\'\":;]+)\\s*:\\s*(\"(?:\\\\.|[^\"])*\"|[^\"\\s;]+)[\\s;]*" */
+    while (len > 0) {
+	const struct modeset *p = modesets;
+	int n = 0;
+
+	for (; len > 0 && *str; str++, --len) {
+	    switch (*str) {
+	      case '\'': case '"': case ':': case ';':
+		continue;
+	    }
+	    if (!ISSPACE(*str)) break;
+	}
+	for (beg = str; len > 0; str++, --len) {
+	    switch (*str) {
+	      case '\'': case '"': case ':': case ';':
+		break;
+	      default:
+		if (ISSPACE(*str)) break;
+		continue;
+	    }
+	    break;
+	}
+	for (end = str; len > 0 && ISSPACE(*str); str++, --len);
+	if (!len) break;
+	if (*str != ':') continue;
+
+	do str++; while (--len > 0 && ISSPACE(*str));
+	if (!len) break;
+	if (*str == '"') {
+	    for (vbeg = ++str; --len > 0 && *str != '"'; str++) {
+		if (*str == '\\') {
+		    --len;
+		    ++str;
+		}
+	    }
+	    vend = str;
+	    if (len) {
+		--len;
+		++str;
+	    }
+	}
+	else {
+	    for (vbeg = str; len > 0 && *str != '"' && !ISSPACE(*str); --len, str++);
+	    vend = str;
+	}
+	while (len > 0 && (*str == ';' || ISSPACE(*str))) --len, str++;
+
+	str_copy(name, beg, end - beg);
+	rb_funcall(name, rb_intern("downcase!"), 0);
+	do {
+	    if (strncmp(p->name, RSTRING(name)->ptr, n) == 0) {
+		str_copy(val, vbeg, vend - vbeg);
+		(*p->func)(RSTRING(val)->ptr, RSTRING(name)->ptr);
+		break;
+	    }
+	} while (++p < modesets + sizeof(modesets) / sizeof(*p));
+    }
+}
+
 static void
 process_sflag()
@@ -967,4 +1090,7 @@ load_file(fname, script)
 		}
 	    }
+	    else if (RSTRING(line)->len > 7) {
+		ruby_modeset(RSTRING(line)->ptr, RSTRING(line)->len);
+	    }
 	}
 	else if (!NIL_P(c)) {


-- 
Nobu Nakada