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Diffstat (limited to 'gfx/harfbuzz/src/hb-blob.cc')
| -rw-r--r-- | gfx/harfbuzz/src/hb-blob.cc | 478 |
1 files changed, 478 insertions, 0 deletions
diff --git a/gfx/harfbuzz/src/hb-blob.cc b/gfx/harfbuzz/src/hb-blob.cc new file mode 100644 index 000000000..fb48f03ca --- /dev/null +++ b/gfx/harfbuzz/src/hb-blob.cc @@ -0,0 +1,478 @@ +/* + * Copyright © 2009 Red Hat, Inc. + * + * This is part of HarfBuzz, a text shaping library. + * + * Permission is hereby granted, without written agreement and without + * license or royalty fees, to use, copy, modify, and distribute this + * software and its documentation for any purpose, provided that the + * above copyright notice and the following two paragraphs appear in + * all copies of this software. + * + * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR + * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES + * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN + * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH + * DAMAGE. + * + * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, + * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND + * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS + * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO + * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. + * + * Red Hat Author(s): Behdad Esfahbod + */ + +/* http://www.oracle.com/technetwork/articles/servers-storage-dev/standardheaderfiles-453865.html */ +#ifndef _POSIX_C_SOURCE +#define _POSIX_C_SOURCE 199309L +#endif + +#include "hb-private.hh" + +#include "hb-object-private.hh" + +#ifdef HAVE_SYS_MMAN_H +#ifdef HAVE_UNISTD_H +#include <unistd.h> +#endif /* HAVE_UNISTD_H */ +#include <sys/mman.h> +#endif /* HAVE_SYS_MMAN_H */ + +#include <stdio.h> +#include <errno.h> + + + +#ifndef HB_DEBUG_BLOB +#define HB_DEBUG_BLOB (HB_DEBUG+0) +#endif + + +struct hb_blob_t { + hb_object_header_t header; + ASSERT_POD (); + + bool immutable; + + const char *data; + unsigned int length; + hb_memory_mode_t mode; + + void *user_data; + hb_destroy_func_t destroy; +}; + + +static bool _try_writable (hb_blob_t *blob); + +static void +_hb_blob_destroy_user_data (hb_blob_t *blob) +{ + if (blob->destroy) { + blob->destroy (blob->user_data); + blob->user_data = NULL; + blob->destroy = NULL; + } +} + +/** + * hb_blob_create: (skip) + * @data: Pointer to blob data. + * @length: Length of @data in bytes. + * @mode: Memory mode for @data. + * @user_data: Data parameter to pass to @destroy. + * @destroy: Callback to call when @data is not needed anymore. + * + * Creates a new "blob" object wrapping @data. The @mode parameter is used + * to negotiate ownership and lifecycle of @data. + * + * Return value: New blob, or the empty blob if something failed or if @length is + * zero. Destroy with hb_blob_destroy(). + * + * Since: 0.9.2 + **/ +hb_blob_t * +hb_blob_create (const char *data, + unsigned int length, + hb_memory_mode_t mode, + void *user_data, + hb_destroy_func_t destroy) +{ + hb_blob_t *blob; + + if (!length || + length >= 1u << 31 || + !(blob = hb_object_create<hb_blob_t> ())) { + if (destroy) + destroy (user_data); + return hb_blob_get_empty (); + } + + blob->data = data; + blob->length = length; + blob->mode = mode; + + blob->user_data = user_data; + blob->destroy = destroy; + + if (blob->mode == HB_MEMORY_MODE_DUPLICATE) { + blob->mode = HB_MEMORY_MODE_READONLY; + if (!_try_writable (blob)) { + hb_blob_destroy (blob); + return hb_blob_get_empty (); + } + } + + return blob; +} + +/** + * hb_blob_create_sub_blob: + * @parent: Parent blob. + * @offset: Start offset of sub-blob within @parent, in bytes. + * @length: Length of sub-blob. + * + * Returns a blob that represents a range of bytes in @parent. The new + * blob is always created with %HB_MEMORY_MODE_READONLY, meaning that it + * will never modify data in the parent blob. The parent data is not + * expected to be modified, and will result in undefined behavior if it + * is. + * + * Makes @parent immutable. + * + * Return value: New blob, or the empty blob if something failed or if + * @length is zero or @offset is beyond the end of @parent's data. Destroy + * with hb_blob_destroy(). + * + * Since: 0.9.2 + **/ +hb_blob_t * +hb_blob_create_sub_blob (hb_blob_t *parent, + unsigned int offset, + unsigned int length) +{ + hb_blob_t *blob; + + if (!length || offset >= parent->length) + return hb_blob_get_empty (); + + hb_blob_make_immutable (parent); + + blob = hb_blob_create (parent->data + offset, + MIN (length, parent->length - offset), + HB_MEMORY_MODE_READONLY, + hb_blob_reference (parent), + (hb_destroy_func_t) hb_blob_destroy); + + return blob; +} + +/** + * hb_blob_get_empty: + * + * Returns the singleton empty blob. + * + * See TODO:link object types for more information. + * + * Return value: (transfer full): the empty blob. + * + * Since: 0.9.2 + **/ +hb_blob_t * +hb_blob_get_empty (void) +{ + static const hb_blob_t _hb_blob_nil = { + HB_OBJECT_HEADER_STATIC, + + true, /* immutable */ + + NULL, /* data */ + 0, /* length */ + HB_MEMORY_MODE_READONLY, /* mode */ + + NULL, /* user_data */ + NULL /* destroy */ + }; + + return const_cast<hb_blob_t *> (&_hb_blob_nil); +} + +/** + * hb_blob_reference: (skip) + * @blob: a blob. + * + * Increases the reference count on @blob. + * + * See TODO:link object types for more information. + * + * Return value: @blob. + * + * Since: 0.9.2 + **/ +hb_blob_t * +hb_blob_reference (hb_blob_t *blob) +{ + return hb_object_reference (blob); +} + +/** + * hb_blob_destroy: (skip) + * @blob: a blob. + * + * Descreases the reference count on @blob, and if it reaches zero, destroys + * @blob, freeing all memory, possibly calling the destroy-callback the blob + * was created for if it has not been called already. + * + * See TODO:link object types for more information. + * + * Since: 0.9.2 + **/ +void +hb_blob_destroy (hb_blob_t *blob) +{ + if (!hb_object_destroy (blob)) return; + + _hb_blob_destroy_user_data (blob); + + free (blob); +} + +/** + * hb_blob_set_user_data: (skip) + * @blob: a blob. + * @key: key for data to set. + * @data: data to set. + * @destroy: callback to call when @data is not needed anymore. + * @replace: whether to replace an existing data with the same key. + * + * Return value: + * + * Since: 0.9.2 + **/ +hb_bool_t +hb_blob_set_user_data (hb_blob_t *blob, + hb_user_data_key_t *key, + void * data, + hb_destroy_func_t destroy, + hb_bool_t replace) +{ + return hb_object_set_user_data (blob, key, data, destroy, replace); +} + +/** + * hb_blob_get_user_data: (skip) + * @blob: a blob. + * @key: key for data to get. + * + * + * + * Return value: (transfer none): + * + * Since: 0.9.2 + **/ +void * +hb_blob_get_user_data (hb_blob_t *blob, + hb_user_data_key_t *key) +{ + return hb_object_get_user_data (blob, key); +} + + +/** + * hb_blob_make_immutable: + * @blob: a blob. + * + * + * + * Since: 0.9.2 + **/ +void +hb_blob_make_immutable (hb_blob_t *blob) +{ + if (hb_object_is_inert (blob)) + return; + + blob->immutable = true; +} + +/** + * hb_blob_is_immutable: + * @blob: a blob. + * + * + * + * Return value: TODO + * + * Since: 0.9.2 + **/ +hb_bool_t +hb_blob_is_immutable (hb_blob_t *blob) +{ + return blob->immutable; +} + + +/** + * hb_blob_get_length: + * @blob: a blob. + * + * + * + * Return value: the length of blob data in bytes. + * + * Since: 0.9.2 + **/ +unsigned int +hb_blob_get_length (hb_blob_t *blob) +{ + return blob->length; +} + +/** + * hb_blob_get_data: + * @blob: a blob. + * @length: (out): + * + * + * + * Returns: (transfer none) (array length=length): + * + * Since: 0.9.2 + **/ +const char * +hb_blob_get_data (hb_blob_t *blob, unsigned int *length) +{ + if (length) + *length = blob->length; + + return blob->data; +} + +/** + * hb_blob_get_data_writable: + * @blob: a blob. + * @length: (out): output length of the writable data. + * + * Tries to make blob data writable (possibly copying it) and + * return pointer to data. + * + * Fails if blob has been made immutable, or if memory allocation + * fails. + * + * Returns: (transfer none) (array length=length): Writable blob data, + * or %NULL if failed. + * + * Since: 0.9.2 + **/ +char * +hb_blob_get_data_writable (hb_blob_t *blob, unsigned int *length) +{ + if (!_try_writable (blob)) { + if (length) + *length = 0; + + return NULL; + } + + if (length) + *length = blob->length; + + return const_cast<char *> (blob->data); +} + + +static hb_bool_t +_try_make_writable_inplace_unix (hb_blob_t *blob) +{ +#if defined(HAVE_SYS_MMAN_H) && defined(HAVE_MPROTECT) + uintptr_t pagesize = -1, mask, length; + const char *addr; + +#if defined(HAVE_SYSCONF) && defined(_SC_PAGE_SIZE) + pagesize = (uintptr_t) sysconf (_SC_PAGE_SIZE); +#elif defined(HAVE_SYSCONF) && defined(_SC_PAGESIZE) + pagesize = (uintptr_t) sysconf (_SC_PAGESIZE); +#elif defined(HAVE_GETPAGESIZE) + pagesize = (uintptr_t) getpagesize (); +#endif + + if ((uintptr_t) -1L == pagesize) { + DEBUG_MSG_FUNC (BLOB, blob, "failed to get pagesize: %s", strerror (errno)); + return false; + } + DEBUG_MSG_FUNC (BLOB, blob, "pagesize is %lu", (unsigned long) pagesize); + + mask = ~(pagesize-1); + addr = (const char *) (((uintptr_t) blob->data) & mask); + length = (const char *) (((uintptr_t) blob->data + blob->length + pagesize-1) & mask) - addr; + DEBUG_MSG_FUNC (BLOB, blob, + "calling mprotect on [%p..%p] (%lu bytes)", + addr, addr+length, (unsigned long) length); + if (-1 == mprotect ((void *) addr, length, PROT_READ | PROT_WRITE)) { + DEBUG_MSG_FUNC (BLOB, blob, "mprotect failed: %s", strerror (errno)); + return false; + } + + blob->mode = HB_MEMORY_MODE_WRITABLE; + + DEBUG_MSG_FUNC (BLOB, blob, + "successfully made [%p..%p] (%lu bytes) writable\n", + addr, addr+length, (unsigned long) length); + return true; +#else + return false; +#endif +} + +static bool +_try_writable_inplace (hb_blob_t *blob) +{ + DEBUG_MSG_FUNC (BLOB, blob, "making writable inplace\n"); + + if (_try_make_writable_inplace_unix (blob)) + return true; + + DEBUG_MSG_FUNC (BLOB, blob, "making writable -> FAILED\n"); + + /* Failed to make writable inplace, mark that */ + blob->mode = HB_MEMORY_MODE_READONLY; + return false; +} + +static bool +_try_writable (hb_blob_t *blob) +{ + if (blob->immutable) + return false; + + if (blob->mode == HB_MEMORY_MODE_WRITABLE) + return true; + + if (blob->mode == HB_MEMORY_MODE_READONLY_MAY_MAKE_WRITABLE && _try_writable_inplace (blob)) + return true; + + if (blob->mode == HB_MEMORY_MODE_WRITABLE) + return true; + + + DEBUG_MSG_FUNC (BLOB, blob, "current data is -> %p\n", blob->data); + + char *new_data; + + new_data = (char *) malloc (blob->length); + if (unlikely (!new_data)) + return false; + + DEBUG_MSG_FUNC (BLOB, blob, "dupped successfully -> %p\n", blob->data); + + memcpy (new_data, blob->data, blob->length); + _hb_blob_destroy_user_data (blob); + blob->mode = HB_MEMORY_MODE_WRITABLE; + blob->data = new_data; + blob->user_data = new_data; + blob->destroy = free; + + return true; +} |