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 #if defined(_POSIX_C_SOURCE)
29 #undef _POSIX_C_SOURCE
31 #define _POSIX_C_SOURCE 199309L
33 #include "hb-private.hh"
36 #include "hb-object-private.hh"
38 #ifdef HAVE_SYS_MMAN_H
41 #endif /* HAVE_UNISTD_H */
43 #endif /* HAVE_SYS_MMAN_H */
51 #define HB_DEBUG_BLOB (HB_DEBUG+0)
56 hb_object_header_t header;
63 hb_memory_mode_t mode;
66 hb_destroy_func_t destroy;
70 static bool _try_writable (hb_blob_t *blob);
73 _hb_blob_destroy_user_data (hb_blob_t *blob)
76 blob->destroy (blob->user_data);
77 blob->user_data = NULL;
83 hb_blob_create (const char *data,
85 hb_memory_mode_t mode,
87 hb_destroy_func_t destroy)
91 if (!length || !(blob = hb_object_create<hb_blob_t> ())) {
94 return hb_blob_get_empty ();
98 blob->length = length;
101 blob->user_data = user_data;
102 blob->destroy = destroy;
104 if (blob->mode == HB_MEMORY_MODE_DUPLICATE) {
105 blob->mode = HB_MEMORY_MODE_READONLY;
106 if (!_try_writable (blob)) {
107 hb_blob_destroy (blob);
108 return hb_blob_get_empty ();
116 hb_blob_create_sub_blob (hb_blob_t *parent,
122 if (!length || offset >= parent->length)
123 return hb_blob_get_empty ();
125 hb_blob_make_immutable (parent);
127 blob = hb_blob_create (parent->data + offset,
128 MIN (length, parent->length - offset),
129 HB_MEMORY_MODE_READONLY,
130 hb_blob_reference (parent),
131 (hb_destroy_func_t) hb_blob_destroy);
137 hb_blob_get_empty (void)
139 static const hb_blob_t _hb_blob_nil = {
140 HB_OBJECT_HEADER_STATIC,
142 true, /* immutable */
146 HB_MEMORY_MODE_READONLY, /* mode */
148 NULL, /* user_data */
152 return const_cast<hb_blob_t *> (&_hb_blob_nil);
156 hb_blob_reference (hb_blob_t *blob)
158 return hb_object_reference (blob);
162 hb_blob_destroy (hb_blob_t *blob)
164 if (!hb_object_destroy (blob)) return;
166 _hb_blob_destroy_user_data (blob);
172 hb_blob_set_user_data (hb_blob_t *blob,
173 hb_user_data_key_t *key,
175 hb_destroy_func_t destroy,
178 return hb_object_set_user_data (blob, key, data, destroy, replace);
182 hb_blob_get_user_data (hb_blob_t *blob,
183 hb_user_data_key_t *key)
185 return hb_object_get_user_data (blob, key);
190 hb_blob_make_immutable (hb_blob_t *blob)
192 if (hb_object_is_inert (blob))
195 blob->immutable = true;
199 hb_blob_is_immutable (hb_blob_t *blob)
201 return blob->immutable;
206 hb_blob_get_length (hb_blob_t *blob)
212 hb_blob_get_data (hb_blob_t *blob, unsigned int *length)
215 *length = blob->length;
221 hb_blob_get_data_writable (hb_blob_t *blob, unsigned int *length)
223 if (!_try_writable (blob)) {
231 *length = blob->length;
233 return const_cast<char *> (blob->data);
238 _try_make_writable_inplace_unix (hb_blob_t *blob)
240 #if defined(HAVE_SYS_MMAN_H) && defined(HAVE_MPROTECT)
241 uintptr_t pagesize = -1, mask, length;
244 #if defined(HAVE_SYSCONF) && defined(_SC_PAGE_SIZE)
245 pagesize = (uintptr_t) sysconf (_SC_PAGE_SIZE);
246 #elif defined(HAVE_SYSCONF) && defined(_SC_PAGESIZE)
247 pagesize = (uintptr_t) sysconf (_SC_PAGESIZE);
248 #elif defined(HAVE_GETPAGESIZE)
249 pagesize = (uintptr_t) getpagesize ();
252 if ((uintptr_t) -1L == pagesize) {
253 DEBUG_MSG_FUNC (BLOB, blob, "failed to get pagesize: %s", strerror (errno));
256 DEBUG_MSG_FUNC (BLOB, blob, "pagesize is %lu", (unsigned long) pagesize);
258 mask = ~(pagesize-1);
259 addr = (const char *) (((uintptr_t) blob->data) & mask);
260 length = (const char *) (((uintptr_t) blob->data + blob->length + pagesize-1) & mask) - addr;
261 DEBUG_MSG_FUNC (BLOB, blob,
262 "calling mprotect on [%p..%p] (%lu bytes)",
263 addr, addr+length, (unsigned long) length);
264 if (-1 == mprotect ((void *) addr, length, PROT_READ | PROT_WRITE)) {
265 DEBUG_MSG_FUNC (BLOB, blob, "mprotect failed: %s", strerror (errno));
269 blob->mode = HB_MEMORY_MODE_WRITABLE;
271 DEBUG_MSG_FUNC (BLOB, blob,
272 "successfully made [%p..%p] (%lu bytes) writable\n",
273 addr, addr+length, (unsigned long) length);
281 _try_writable_inplace (hb_blob_t *blob)
283 DEBUG_MSG_FUNC (BLOB, blob, "making writable inplace\n");
285 if (_try_make_writable_inplace_unix (blob))
288 DEBUG_MSG_FUNC (BLOB, blob, "making writable -> FAILED\n");
290 /* Failed to make writable inplace, mark that */
291 blob->mode = HB_MEMORY_MODE_READONLY;
296 _try_writable (hb_blob_t *blob)
301 if (blob->mode == HB_MEMORY_MODE_WRITABLE)
304 if (blob->mode == HB_MEMORY_MODE_READONLY_MAY_MAKE_WRITABLE && _try_writable_inplace (blob))
307 if (blob->mode == HB_MEMORY_MODE_WRITABLE)
311 DEBUG_MSG_FUNC (BLOB, blob, "current data is -> %p\n", blob->data);
315 new_data = (char *) malloc (blob->length);
316 if (unlikely (!new_data))
319 DEBUG_MSG_FUNC (BLOB, blob, "dupped successfully -> %p\n", blob->data);
321 memcpy (new_data, blob->data, blob->length);
322 _hb_blob_destroy_user_data (blob);
323 blob->mode = HB_MEMORY_MODE_WRITABLE;
324 blob->data = new_data;
325 blob->user_data = new_data;
326 blob->destroy = free;