| /* |
| * 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" |
| |
| #if !defined(STARBOARD) |
| #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> |
| #endif |
| |
| |
| |
| #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 || |
| data + length < data /* overflows */ || |
| !(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; |
| } |