2 * Copyright 2012 Jacek Caban for CodeWeavers
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with this library; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
20 * This is a common header for all string representations. The exact layout of the string
21 * representation may be:
23 * - inline string - string bytes directly follow string headers.
24 * - heap string - a structure containing a pointer to buffer on the heap.
25 * - roper string - a product of concatenation of two strings. Instead of copying whole
26 * buffers, we may store just references to concatenated strings.
28 * String layout may change over life time of the string. Currently possible transformation
29 * is when a rope string becomes a heap stream. That happens when we need a real, linear
30 * zero-terminated buffer (a flat buffer). At this point the type of the string is changed
31 * and the new buffer is stored in the string, so that subsequent operations requiring
32 * a flat string won't need to flatten it again.
34 * In the future more layouts and transformations may be added.
37 unsigned length_flags;
41 #define JSSTR_LENGTH_SHIFT 4
42 #define JSSTR_MAX_LENGTH (1 << (32-JSSTR_LENGTH_SHIFT))
43 #define JSSTR_FLAGS_MASK ((1 << JSSTR_LENGTH_SHIFT)-1)
45 #define JSSTR_FLAG_NULLBSTR 4
47 #define JSSTR_FLAG_LBIT 1
48 #define JSSTR_FLAG_FLAT 2
49 #define JSSTR_FLAG_TAG_MASK 3
52 JSSTR_INLINE = JSSTR_FLAG_FLAT,
53 JSSTR_HEAP = JSSTR_FLAG_FLAT|JSSTR_FLAG_LBIT,
54 JSSTR_ROPE = JSSTR_FLAG_LBIT
57 static inline unsigned jsstr_length(jsstr_t *str)
59 return str->length_flags >> JSSTR_LENGTH_SHIFT;
62 static inline jsstr_tag_t jsstr_tag(jsstr_t *str)
64 return str->length_flags & JSSTR_FLAG_TAG_MASK;
67 static inline BOOL jsstr_is_inline(jsstr_t *str)
69 return jsstr_tag(str) == JSSTR_INLINE;
72 static inline BOOL jsstr_is_heap(jsstr_t *str)
74 return jsstr_tag(str) == JSSTR_HEAP;
77 static inline BOOL jsstr_is_rope(jsstr_t *str)
79 return jsstr_tag(str) == JSSTR_ROPE;
99 jsstr_t *jsstr_alloc_len(const WCHAR*,unsigned) DECLSPEC_HIDDEN;
100 WCHAR *jsstr_alloc_buf(unsigned,jsstr_t**) DECLSPEC_HIDDEN;
102 static inline jsstr_t *jsstr_alloc(const WCHAR *str)
104 return jsstr_alloc_len(str, strlenW(str));
107 void jsstr_free(jsstr_t*) DECLSPEC_HIDDEN;
109 static inline void jsstr_release(jsstr_t *str)
112 if(jsstr_is_inline(str))
119 static inline jsstr_t *jsstr_addref(jsstr_t *str)
125 static inline jsstr_inline_t *jsstr_as_inline(jsstr_t *str)
127 return CONTAINING_RECORD(str, jsstr_inline_t, str);
130 static inline jsstr_heap_t *jsstr_as_heap(jsstr_t *str)
132 return CONTAINING_RECORD(str, jsstr_heap_t, str);
135 static inline jsstr_rope_t *jsstr_as_rope(jsstr_t *str)
137 return CONTAINING_RECORD(str, jsstr_rope_t, str);
140 const WCHAR *jsstr_rope_flatten(jsstr_rope_t*) DECLSPEC_HIDDEN;
142 static inline const WCHAR *jsstr_flatten(jsstr_t *str)
144 return jsstr_is_inline(str) ? jsstr_as_inline(str)->buf
145 : jsstr_is_heap(str) ? jsstr_as_heap(str)->buf
146 : jsstr_rope_flatten(jsstr_as_rope(str));
149 void jsstr_extract(jsstr_t*,unsigned,unsigned,WCHAR*) DECLSPEC_HIDDEN;
151 static inline unsigned jsstr_flush(jsstr_t *str, WCHAR *buf)
153 unsigned len = jsstr_length(str);
154 if(jsstr_is_inline(str)) {
155 memcpy(buf, jsstr_as_inline(str)->buf, len*sizeof(WCHAR));
156 }else if(jsstr_is_heap(str)) {
157 memcpy(buf, jsstr_as_heap(str)->buf, len*sizeof(WCHAR));
159 jsstr_rope_t *rope = jsstr_as_rope(str);
160 jsstr_flush(rope->left, buf);
161 jsstr_flush(rope->right, buf+jsstr_length(rope->left));
166 static inline jsstr_t *jsstr_substr(jsstr_t *str, unsigned off, unsigned len)
171 ptr = jsstr_alloc_buf(len, &ret);
173 jsstr_extract(str, off, len, ptr);
177 int jsstr_cmp(jsstr_t*,jsstr_t*) DECLSPEC_HIDDEN;
179 static inline BOOL jsstr_eq(jsstr_t *left, jsstr_t *right)
181 return jsstr_length(left) == jsstr_length(right) && !jsstr_cmp(left, right);
184 jsstr_t *jsstr_concat(jsstr_t*,jsstr_t*) DECLSPEC_HIDDEN;
186 jsstr_t *jsstr_nan(void) DECLSPEC_HIDDEN;
187 jsstr_t *jsstr_empty(void) DECLSPEC_HIDDEN;
188 jsstr_t *jsstr_undefined(void) DECLSPEC_HIDDEN;
190 BOOL init_strings(void) DECLSPEC_HIDDEN;
191 void free_strings(void) DECLSPEC_HIDDEN;
193 const char *debugstr_jsstr(jsstr_t*) DECLSPEC_HIDDEN;