hb-blob.cc | Explore in Territory

/*
 * Copyright © 2009  Red Hat, Inc.
 * Copyright © 2018  Ebrahim Byagowi
 *
 *  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
 */

#include "hb.hh"
#include "hb-blob.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 */


/**
 * SECTION: hb-blob
 * @title: hb-blob
 * @short_description: Binary data containers
 * @include: hb.h
 *
 * Blobs wrap a chunk of binary data to handle lifecycle management of data
 * while it is passed between client and HarfBuzz.  Blobs are primarily used
 * to create font faces, but also to access font face tables, as well as
 * pass around other binary data.
 **/


/**
 * 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: (nullable): 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_create_or_fail: (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: (nullable): 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.
 *
 * Note that this function returns a freshly-allocated empty blob even if @length
 * is zero. This is in contrast to hb_blob_create(), which returns the singleton
 * empty blob (as returned by hb_blob_get_empty()) if @length is zero.
 *
 * Return value: New blob, or `NULL` if failed.  Destroy with hb_blob_destroy().
 *
 * Since: 2.8.2
 **/
hb_blob_t *
hb_blob_create_or_fail (const char        *data,
			unsigned int       length,
			hb_memory_mode_t   mode,
			void              *user_data,
			hb_destroy_func_t  destroy)
{ … }

static void
_hb_blob_destroy (void *data)
{ … }

/**
 * 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_copy_writable_or_fail:
 * @blob: A blob.
 *
 * Makes a writable copy of @blob.
 *
 * Return value: The new blob, or nullptr if allocation failed
 *
 * Since: 1.8.0
 **/
hb_blob_t *
hb_blob_copy_writable_or_fail (hb_blob_t *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 ()
{ … }

/**
 * 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)
{ … }

/**
 * hb_blob_destroy: (skip)
 * @blob: a blob.
 *
 * Decreases 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)
{ … }

/**
 * hb_blob_set_user_data: (skip)
 * @blob: An #hb_blob_t
 * @key: The user-data key to set
 * @data: A pointer to the user data to set
 * @destroy: (nullable): A callback to call when @data is not needed anymore
 * @replace: Whether to replace an existing data with the same key
 *
 * Attaches a user-data key/data pair to the specified blob.
 *
 * Return value: `true` if success, `false` otherwise
 *
 * 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)
{ … }

/**
 * hb_blob_get_user_data: (skip)
 * @blob: a blob
 * @key: The user-data key to query
 *
 * Fetches the user data associated with the specified key,
 * attached to the specified font-functions structure.
 *
 * Return value: (transfer none): A pointer to the user data
 *
 * Since: 0.9.2
 **/
void *
hb_blob_get_user_data (const hb_blob_t    *blob,
		       hb_user_data_key_t *key)
{ … }


/**
 * hb_blob_make_immutable:
 * @blob: a blob
 *
 * Makes a blob immutable.
 *
 * Since: 0.9.2
 **/
void
hb_blob_make_immutable (hb_blob_t *blob)
{ … }

/**
 * hb_blob_is_immutable:
 * @blob: a blob.
 *
 * Tests whether a blob is immutable.
 *
 * Return value: `true` if @blob is immutable, `false` otherwise
 *
 * Since: 0.9.2
 **/
hb_bool_t
hb_blob_is_immutable (hb_blob_t *blob)
{ … }


/**
 * hb_blob_get_length:
 * @blob: a blob.
 *
 * Fetches the length of a blob's data.
 *
 * Return value: the length of @blob data in bytes.
 *
 * Since: 0.9.2
 **/
unsigned int
hb_blob_get_length (hb_blob_t *blob)
{ … }

/**
 * hb_blob_get_data:
 * @blob: a blob.
 * @length: (out): The length in bytes of the data retrieved
 *
 * Fetches the data from a blob.
 *
 * Returns: (nullable) (transfer none) (array length=length): the byte data of @blob.
 *
 * Since: 0.9.2
 **/
const char *
hb_blob_get_data (hb_blob_t *blob, unsigned int *length)
{ … }

/**
 * 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)
{ … }


bool
hb_blob_t::try_make_writable_inplace_unix ()
{ … }

bool
hb_blob_t::try_make_writable_inplace ()
{ … }

bool
hb_blob_t::try_make_writable ()
{ … }

/*
 * Mmap
 */

#ifndef HB_NO_OPEN
#ifdef HAVE_MMAP
# if !defined(HB_NO_RESOURCE_FORK) && defined(__APPLE__)
#  include <sys/paths.h>
# endif
# include <sys/types.h>
# include <sys/stat.h>
# include <fcntl.h>
#endif

#ifdef _WIN32
# include <windows.h>
#else
# ifndef O_BINARY
#define O_BINARY …
# endif
#endif

#ifndef MAP_NORESERVE
#define MAP_NORESERVE …
#endif

struct hb_mapped_file_t
{ … };

#if (defined(HAVE_MMAP) || defined(_WIN32)) && !defined(HB_NO_MMAP)
static void
_hb_mapped_file_destroy (void *file_)
{
  hb_mapped_file_t *file = (hb_mapped_file_t *) file_;
#ifdef HAVE_MMAP
  munmap (file->contents, file->length);
#elif defined(_WIN32)
  UnmapViewOfFile (file->contents);
  CloseHandle (file->mapping);
#else
  assert (0); // If we don't have mmap we shouldn't reach here
#endif

  hb_free (file);
}
#endif

#ifdef _PATH_RSRCFORKSPEC
static int
_open_resource_fork (const char *file_name, hb_mapped_file_t *file)
{
  size_t name_len = strlen (file_name);
  size_t len = name_len + sizeof (_PATH_RSRCFORKSPEC);

  char *rsrc_name = (char *) hb_malloc (len);
  if (unlikely (!rsrc_name)) return -1;

  strncpy (rsrc_name, file_name, name_len);
  strncpy (rsrc_name + name_len, _PATH_RSRCFORKSPEC,
	   sizeof (_PATH_RSRCFORKSPEC));

  int fd = open (rsrc_name, O_RDONLY | O_BINARY, 0);
  hb_free (rsrc_name);

  if (fd != -1)
  {
    struct stat st;
    if (fstat (fd, &st) != -1)
      file->length = (unsigned long) st.st_size;
    else
    {
      close (fd);
      fd = -1;
    }
  }

  return fd;
}
#endif

/**
 * hb_blob_create_from_file:
 * @file_name: A font filename
 *
 * Creates a new blob containing the data from the
 * specified binary font file.
 *
 * The filename is passed directly to the system on all platforms,
 * except on Windows, where the filename is interpreted as UTF-8.
 * Only if the filename is not valid UTF-8, it will be interpreted
 * according to the system codepage.
 *
 * Returns: An #hb_blob_t pointer with the content of the file,
 * or hb_blob_get_empty() if failed.
 *
 * Since: 1.7.7
 **/
hb_blob_t *
hb_blob_create_from_file (const char *file_name)
{ … }

/**
 * hb_blob_create_from_file_or_fail:
 * @file_name: A font filename
 *
 * Creates a new blob containing the data from the
 * specified binary font file.
 *
 * The filename is passed directly to the system on all platforms,
 * except on Windows, where the filename is interpreted as UTF-8.
 * Only if the filename is not valid UTF-8, it will be interpreted
 * according to the system codepage.
 *
 * Returns: An #hb_blob_t pointer with the content of the file,
 * or `NULL` if failed.
 *
 * Since: 2.8.2
 **/
hb_blob_t *
hb_blob_create_from_file_or_fail (const char *file_name)
{ … }
#endif /* !HB_NO_OPEN */
chromium/third_party/harfbuzz-ng/src/src/hb-blob.cc
