2 * Copyright © 2009 Red Hat, Inc.
4 * This is part of HarfBuzz, a text shaping library.
6 * Permission is hereby granted, without written agreement and without
7 * license or royalty fees, to use, copy, modify, and distribute this
8 * software and its documentation for any purpose, provided that the
9 * above copyright notice and the following two paragraphs appear in
10 * all copies of this software.
12 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
13 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
14 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
15 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
18 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
19 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
20 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
21 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
22 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
24 * Red Hat Author(s): Behdad Esfahbod
27 /* http://www.oracle.com/technetwork/articles/servers-storage-dev/standardheaderfiles-453865.html */
28 #define _POSIX_C_SOURCE 199309L
30 #include "hb-private.hh"
33 #include "hb-object-private.hh"
35 #ifdef HAVE_SYS_MMAN_H
38 #endif /* HAVE_UNISTD_H */
40 #endif /* HAVE_SYS_MMAN_H */
48 #define HB_DEBUG_BLOB (HB_DEBUG+0)
53 hb_object_header_t header;
60 hb_memory_mode_t mode;
63 hb_destroy_func_t destroy;
67 static bool _try_writable (hb_blob_t *blob);
70 _hb_blob_destroy_user_data (hb_blob_t *blob)
73 blob->destroy (blob->user_data);
74 blob->user_data = NULL;
80 hb_blob_create (const char *data,
82 hb_memory_mode_t mode,
84 hb_destroy_func_t destroy)
88 if (!length || !(blob = hb_object_create<hb_blob_t> ())) {
91 return hb_blob_get_empty ();
95 blob->length = length;
98 blob->user_data = user_data;
99 blob->destroy = destroy;
101 if (blob->mode == HB_MEMORY_MODE_DUPLICATE) {
102 blob->mode = HB_MEMORY_MODE_READONLY;
103 if (!_try_writable (blob)) {
104 hb_blob_destroy (blob);
105 return hb_blob_get_empty ();
113 hb_blob_create_sub_blob (hb_blob_t *parent,
119 if (!length || offset >= parent->length)
120 return hb_blob_get_empty ();
122 hb_blob_make_immutable (parent);
124 blob = hb_blob_create (parent->data + offset,
125 MIN (length, parent->length - offset),
127 hb_blob_reference (parent),
128 (hb_destroy_func_t) hb_blob_destroy);
134 hb_blob_get_empty (void)
136 static const hb_blob_t _hb_blob_nil = {
137 HB_OBJECT_HEADER_STATIC,
139 true, /* immutable */
143 HB_MEMORY_MODE_READONLY, /* mode */
145 NULL, /* user_data */
149 return const_cast<hb_blob_t *> (&_hb_blob_nil);
153 hb_blob_reference (hb_blob_t *blob)
155 return hb_object_reference (blob);
159 hb_blob_destroy (hb_blob_t *blob)
161 if (!hb_object_destroy (blob)) return;
163 _hb_blob_destroy_user_data (blob);
169 hb_blob_set_user_data (hb_blob_t *blob,
170 hb_user_data_key_t *key,
172 hb_destroy_func_t destroy,
175 return hb_object_set_user_data (blob, key, data, destroy, replace);
179 hb_blob_get_user_data (hb_blob_t *blob,
180 hb_user_data_key_t *key)
182 return hb_object_get_user_data (blob, key);
187 hb_blob_make_immutable (hb_blob_t *blob)
189 if (hb_object_is_inert (blob))
192 blob->immutable = true;
196 hb_blob_is_immutable (hb_blob_t *blob)
198 return blob->immutable;
203 hb_blob_get_length (hb_blob_t *blob)
209 hb_blob_get_data (hb_blob_t *blob, unsigned int *length)
212 *length = blob->length;
218 hb_blob_get_data_writable (hb_blob_t *blob, unsigned int *length)
220 if (!_try_writable (blob)) {
228 *length = blob->length;
230 return const_cast<char *> (blob->data);
235 _try_make_writable_inplace_unix (hb_blob_t *blob)
237 #if defined(HAVE_SYS_MMAN_H) && defined(HAVE_MPROTECT)
238 uintptr_t pagesize = -1, mask, length;
241 #if defined(HAVE_SYSCONF) && defined(_SC_PAGE_SIZE)
242 pagesize = (uintptr_t) sysconf (_SC_PAGE_SIZE);
243 #elif defined(HAVE_SYSCONF) && defined(_SC_PAGESIZE)
244 pagesize = (uintptr_t) sysconf (_SC_PAGESIZE);
245 #elif defined(HAVE_GETPAGESIZE)
246 pagesize = (uintptr_t) getpagesize ();
249 if ((uintptr_t) -1L == pagesize) {
250 DEBUG_MSG_FUNC (BLOB, blob, "failed to get pagesize: %s", strerror (errno));
253 DEBUG_MSG_FUNC (BLOB, blob, "pagesize is %lu", (unsigned long) pagesize);
255 mask = ~(pagesize-1);
256 addr = (const char *) (((uintptr_t) blob->data) & mask);
257 length = (const char *) (((uintptr_t) blob->data + blob->length + pagesize-1) & mask) - addr;
258 DEBUG_MSG_FUNC (BLOB, blob,
259 "calling mprotect on [%p..%p] (%lu bytes)",
260 addr, addr+length, (unsigned long) length);
261 if (-1 == mprotect ((void *) addr, length, PROT_READ | PROT_WRITE)) {
262 DEBUG_MSG_FUNC (BLOB, blob, "mprotect failed: %s", strerror (errno));
266 blob->mode = HB_MEMORY_MODE_WRITABLE;
268 DEBUG_MSG_FUNC (BLOB, blob,
269 "successfully made [%p..%p] (%lu bytes) writable\n",
270 addr, addr+length, (unsigned long) length);
278 _try_writable_inplace (hb_blob_t *blob)
280 DEBUG_MSG_FUNC (BLOB, blob, "making writable inplace\n");
282 if (_try_make_writable_inplace_unix (blob))
285 DEBUG_MSG_FUNC (BLOB, blob, "making writable -> FAILED\n");
287 /* Failed to make writable inplace, mark that */
288 blob->mode = HB_MEMORY_MODE_READONLY;
293 _try_writable (hb_blob_t *blob)
298 if (blob->mode == HB_MEMORY_MODE_WRITABLE)
301 if (blob->mode == HB_MEMORY_MODE_READONLY_MAY_MAKE_WRITABLE && _try_writable_inplace (blob))
304 if (blob->mode == HB_MEMORY_MODE_WRITABLE)
308 DEBUG_MSG_FUNC (BLOB, blob, "current data is -> %p\n", blob->data);
312 new_data = (char *) malloc (blob->length);
313 if (unlikely (!new_data))
316 DEBUG_MSG_FUNC (BLOB, blob, "dupped successfully -> %p\n", blob->data);
318 memcpy (new_data, blob->data, blob->length);
319 _hb_blob_destroy_user_data (blob);
320 blob->mode = HB_MEMORY_MODE_WRITABLE;
321 blob->data = new_data;
322 blob->user_data = new_data;
323 blob->destroy = free;