From f8dee80355c4152b9d16bdafde1283b76b0a2344 Mon Sep 17 00:00:00 2001
From: Bill Currie <bill@taniwha.org>
Date: Thu, 20 Jun 2002 20:28:01 +0000
Subject: [PATCH] add unions

---
 tools/qfcc/include/struct.h  |  1 +
 tools/qfcc/source/qc-lex.l   |  1 +
 tools/qfcc/source/qc-parse.y |  5 ++++-
 tools/qfcc/source/struct.c   | 23 +++++++++++++++++++++--
 4 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/tools/qfcc/include/struct.h b/tools/qfcc/include/struct.h
index 55f4f1108..4f475c94d 100644
--- a/tools/qfcc/include/struct.h
+++ b/tools/qfcc/include/struct.h
@@ -51,6 +51,7 @@ struct_field_t *new_struct_field (struct type_s *strct, struct type_s *type,
 struct_field_t *struct_find_field (struct type_s *strct, const char *name);
 int struct_compare_fields (struct type_s *s1, struct type_s *s2);
 struct type_s *new_struct (const char *name);
+struct type_s *new_union (const char *name);
 struct type_s *find_struct (const char *name);
 void copy_struct_fields (struct type_s *dst, struct type_s *src);
 
diff --git a/tools/qfcc/source/qc-lex.l b/tools/qfcc/source/qc-lex.l
index 816c3c7c9..649c0f5aa 100644
--- a/tools/qfcc/source/qc-lex.l
+++ b/tools/qfcc/source/qc-lex.l
@@ -278,6 +278,7 @@ static keyword_t keywords[] = {
 	{"default",		DEFAULT, 0,					0, PROG_ID_VERSION},
 	{"NIL",			NIL,	0,					0, PROG_ID_VERSION},
 	{"struct",		STRUCT, 0,					0, PROG_VERSION},
+	{"union",		UNION,	0,					0, PROG_VERSION},
 	{"enum",		ENUM,	0,					0, PROG_ID_VERSION},
 	{"typedef",		TYPEDEF, 0,					0, PROG_ID_VERSION},
 	{"super",		SUPER,	0,					0, PROG_VERSION},
diff --git a/tools/qfcc/source/qc-parse.y b/tools/qfcc/source/qc-parse.y
index 3da67651c..e26baaf3b 100644
--- a/tools/qfcc/source/qc-parse.y
+++ b/tools/qfcc/source/qc-parse.y
@@ -126,7 +126,7 @@ void free_local_inits (hashtab_t *def_list);
 
 %token	LOCAL RETURN WHILE DO IF ELSE FOR BREAK CONTINUE ELLIPSIS NIL
 %token	IFBE IFB IFAE IFA
-%token	SWITCH CASE DEFAULT STRUCT ENUM TYPEDEF SUPER SELF THIS
+%token	SWITCH CASE DEFAULT STRUCT UNION ENUM TYPEDEF SUPER SELF THIS
 %token	ARGC ARGV
 %token	ELE_START
 %token	<type> TYPE
@@ -197,6 +197,8 @@ def
 	: type { current_type = $1; } def_list
 	| STRUCT NAME
 	  { struct_type = new_struct ($2); } '=' '{' struct_defs '}'
+	| UNION NAME
+	  { struct_type = new_union ($2); } '=' '{' struct_defs '}'
 	| ENUM '{' enum_list opt_comma '}'
 	  { process_enum ($3); }
 	| TYPEDEF type NAME
@@ -1216,6 +1218,7 @@ reserved_word
 	| DEFAULT					{ $$ = strdup (yytext); }
 	| NIL						{ $$ = strdup (yytext); }
 	| STRUCT					{ $$ = strdup (yytext); }
+	| UNION						{ $$ = strdup (yytext); }
 	| ENUM						{ $$ = strdup (yytext); }
 	| TYPEDEF					{ $$ = strdup (yytext); }
 	| SUPER						{ $$ = strdup (yytext); }
diff --git a/tools/qfcc/source/struct.c b/tools/qfcc/source/struct.c
index dd2a88caa..acc781154 100644
--- a/tools/qfcc/source/struct.c
+++ b/tools/qfcc/source/struct.c
@@ -57,6 +57,7 @@ static const char rcsid[] =
 typedef struct {
 	const char *name;
 	type_t     *type;
+	int         is_union;
 } struct_t;
 
 typedef struct {
@@ -97,8 +98,14 @@ new_struct_field (type_t *strct, type_t *type, const char *name,
 	field->visibility = visibility;
 	field->name = name;
 	field->type = type;
-	field->offset = strct->num_parms;
-	strct->num_parms += type_size (type);
+	if (((struct_t *) strct->class)->is_union) {
+		int         size = type_size (type);
+		field->offset = 0;
+		strct->num_parms = strct->num_parms > size ? strct->num_parms : size;
+	} else {
+		field->offset = strct->num_parms;
+		strct->num_parms += type_size (type);
+	}
 	field->next = 0;
 	*strct->struct_tail = field;
 	strct->struct_tail = &field->next;
@@ -136,6 +143,8 @@ new_struct (const char *name)
 	strct->type->type = ev_struct;
 	strct->type->struct_tail = &strct->type->struct_head;
 	strct->type->struct_fields = Hash_NewTable (61, struct_field_get_key, 0, 0);
+	strct->type->class = (struct class_s *)strct;
+	strct->is_union = 0;
 	if (name) {
 		strct->type->name = strdup (name);
 		Hash_Add (structs, strct);
@@ -143,6 +152,16 @@ new_struct (const char *name)
 	return strct->type;
 }
 
+type_t *
+new_union (const char *name)
+{
+	type_t     *un = new_struct (name);
+
+	if (un)
+		((struct_t *) un->class)->is_union = 1;
+	return un;
+}
+
 type_t *
 find_struct (const char *name)
 {