1 /*
2 * Copyright © 2008 Chris Wilson <chris@chris-wilson.co.uk>
3 *
4 * This library is free software; you can redistribute it and/or
5 * modify it either under the terms of the GNU Lesser General Public
6 * License version 2.1 as published by the Free Software Foundation
7 * (the "LGPL") or, at your option, under the terms of the Mozilla
8 * Public License Version 1.1 (the "MPL"). If you do not alter this
9 * notice, a recipient may use your version of this file under either
10 * the MPL or the LGPL.
11 *
12 * You should have received a copy of the LGPL along with this library
13 * in the file COPYING-LGPL-2.1; if not, write to the Free Software
14 * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
15 * You should have received a copy of the MPL along with this library
16 * in the file COPYING-MPL-1.1
17 *
18 * The contents of this file are subject to the Mozilla Public License
19 * Version 1.1 (the "License"); you may not use this file except in
20 * compliance with the License. You may obtain a copy of the License at
21 * http://www.mozilla.org/MPL/
22 *
23 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
24 * OF ANY KIND, either express or implied. See the LGPL or the MPL for
25 * the specific language governing rights and limitations.
26 *
27 * The Original Code is the cairo graphics library.
28 *
29 * The Initial Developer of the Original Code is Chris Wilson.
30 *
31 * Contributor(s):
32 * Chris Wilson <chris@chris-wilson.co.uk>
33 */
34
35 #include "config.h"
36
37 #include "cairo-script-private.h"
38
39 #include <limits.h> /* INT_MAX */
40 #include <string.h>
41
42 csi_status_t
_csi_stack_init(csi_t * ctx,csi_stack_t * stack,csi_integer_t size)43 _csi_stack_init (csi_t *ctx, csi_stack_t *stack, csi_integer_t size)
44 {
45 csi_status_t status = CSI_STATUS_SUCCESS;
46
47 stack->len = 0;
48 stack->size = size;
49 /* assert ((unsigned) size < INT_MAX / sizeof (csi_object_t)); */
50 stack->objects = _csi_alloc (ctx, size * sizeof (csi_object_t));
51 if (_csi_unlikely (stack->objects == NULL))
52 status = _csi_error (CSI_STATUS_NO_MEMORY);
53
54 return status;
55 }
56
57 void
_csi_stack_fini(csi_t * ctx,csi_stack_t * stack)58 _csi_stack_fini (csi_t *ctx, csi_stack_t *stack)
59 {
60 csi_integer_t n;
61
62 for (n = 0; n < stack->len; n++)
63 csi_object_free (ctx, &stack->objects[n]);
64
65 _csi_free (ctx, stack->objects);
66 }
67
68 csi_status_t
_csi_stack_roll(csi_t * ctx,csi_stack_t * stack,csi_integer_t mod,csi_integer_t n)69 _csi_stack_roll (csi_t *ctx,
70 csi_stack_t *stack,
71 csi_integer_t mod, csi_integer_t n)
72 {
73 csi_object_t stack_copy[128];
74 csi_object_t *copy;
75 csi_integer_t last, i, len;
76
77 switch (mod) { /* special cases */
78 case 1:
79 last = stack->len - 1;
80 stack_copy[0] = stack->objects[last];
81 for (i = last; --n; i--)
82 stack->objects[i] = stack->objects[i-1];
83 stack->objects[i] = stack_copy[0];
84 return CSI_STATUS_SUCCESS;
85 case -1:
86 last = stack->len - 1;
87 stack_copy[0] = stack->objects[i = last - n + 1];
88 for (; --n; i++)
89 stack->objects[i] = stack->objects[i+1];
90 stack->objects[i] = stack_copy[0];
91 return CSI_STATUS_SUCCESS;
92 }
93
94 /* fall back to a copy */
95 if (n > ARRAY_LENGTH (stack_copy)) {
96 if (_csi_unlikely ((unsigned) n > INT_MAX / sizeof (csi_object_t)))
97 return _csi_error (CSI_STATUS_NO_MEMORY);
98 copy = _csi_alloc (ctx, n * sizeof (csi_object_t));
99 if (copy == NULL)
100 return _csi_error (CSI_STATUS_NO_MEMORY);
101 } else
102 copy = stack_copy;
103
104 i = stack->len - n;
105 memcpy (copy, stack->objects + i, n * sizeof (csi_object_t));
106 mod = -mod;
107 if (mod < 0)
108 mod += n;
109 last = mod;
110 for (len = n; n--; i++) {
111 stack->objects[i] = copy[last];
112 if (++last == len)
113 last = 0;
114 }
115
116 if (copy != stack_copy)
117 _csi_free (ctx, copy);
118
119 return CSI_STATUS_SUCCESS;
120 }
121
122 csi_status_t
_csi_stack_grow(csi_t * ctx,csi_stack_t * stack,csi_integer_t cnt)123 _csi_stack_grow (csi_t *ctx, csi_stack_t *stack, csi_integer_t cnt)
124 {
125 csi_integer_t newsize;
126 csi_object_t *newstack;
127
128 if (_csi_likely (cnt <= stack->size))
129 return CSI_STATUS_SUCCESS;
130 if (_csi_unlikely ((unsigned) cnt >= INT_MAX / sizeof (csi_object_t)))
131 return _csi_error (CSI_STATUS_NO_MEMORY);
132
133 newsize = stack->size;
134 do {
135 newsize *= 2;
136 } while (newsize <= cnt);
137
138 newstack = _csi_realloc (ctx,
139 stack->objects,
140 newsize * sizeof (csi_object_t));
141 if (_csi_unlikely (newstack == NULL))
142 return _csi_error (CSI_STATUS_NO_MEMORY);
143
144 stack->objects = newstack;
145 stack->size = newsize;
146
147 return CSI_STATUS_SUCCESS;
148 }
149
150 csi_status_t
_csi_stack_push_internal(csi_t * ctx,csi_stack_t * stack,const csi_object_t * obj)151 _csi_stack_push_internal (csi_t *ctx, csi_stack_t *stack,
152 const csi_object_t *obj)
153 {
154 csi_status_t status;
155
156 status = _csi_stack_grow (ctx, stack, stack->size + 1);
157 if (_csi_unlikely (status))
158 return status;
159
160 stack->objects[stack->len++] = *obj;
161 return CSI_STATUS_SUCCESS;
162 }
163
164 csi_object_t *
_csi_stack_peek(csi_stack_t * stack,csi_integer_t i)165 _csi_stack_peek (csi_stack_t *stack, csi_integer_t i)
166 {
167 if (_csi_unlikely (stack->len < i))
168 return NULL;
169
170 return &stack->objects[stack->len - i -1];
171 }
172
173 void
_csi_stack_pop(csi_t * ctx,csi_stack_t * stack,csi_integer_t count)174 _csi_stack_pop (csi_t *ctx, csi_stack_t *stack, csi_integer_t count)
175 {
176 if (_csi_unlikely (stack->len < count))
177 count = stack->len;
178
179 while (count--)
180 csi_object_free (ctx, &stack->objects[--stack->len]);
181 }
182
183 csi_status_t
_csi_stack_exch(csi_stack_t * stack)184 _csi_stack_exch (csi_stack_t *stack)
185 {
186 csi_object_t tmp;
187 csi_integer_t n;
188
189 if (_csi_unlikely (stack->len < 2))
190 return _csi_error (CSI_STATUS_INVALID_SCRIPT);
191
192 n = stack->len - 1;
193 tmp = stack->objects[n];
194 stack->objects[n] = stack->objects[n - 1];
195 stack->objects[n - 1] = tmp;
196
197 return CSI_STATUS_SUCCESS;
198 }
199