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/****************************************************************************
*
* ftsystem.c
*
* ANSI-specific FreeType low-level system interface (body).
*
* Copyright (C) 1996-2024 by
* David Turner, Robert Wilhelm, and Werner Lemberg.
*
* This file is part of the FreeType project, and may only be used,
* modified, and distributed under the terms of the FreeType project
* license, LICENSE.TXT. By continuing to use, modify, or distribute
* this file you indicate that you have read the license and
* understand and accept it fully.
*
*/
/**************************************************************************
*
* This file contains the default interface used by FreeType to access
* low-level, i.e. memory management, i/o access as well as thread
* synchronisation. It can be replaced by user-specific routines if
* necessary.
*
*/
#include <ft2build.h>
#include FT_CONFIG_CONFIG_H
#include <freetype/internal/ftdebug.h>
#include <freetype/internal/ftstream.h>
#include <freetype/ftsystem.h>
#include <freetype/fterrors.h>
#include <freetype/fttypes.h>
/**************************************************************************
*
* MEMORY MANAGEMENT INTERFACE
*
*/
/**************************************************************************
*
* It is not necessary to do any error checking for the
* allocation-related functions. This will be done by the higher level
* routines like ft_mem_alloc() or ft_mem_realloc().
*
*/
/**************************************************************************
*
* @Function:
* ft_alloc
*
* @Description:
* The memory allocation function.
*
* @Input:
* memory ::
* A pointer to the memory object.
*
* size ::
* The requested size in bytes.
*
* @Return:
* The address of newly allocated block.
*/
FT_CALLBACK_DEF( void* )
ft_alloc( FT_Memory memory,
long size )
{
FT_UNUSED( memory );
return ft_smalloc( (size_t)size );
}
/**************************************************************************
*
* @Function:
* ft_realloc
*
* @Description:
* The memory reallocation function.
*
* @Input:
* memory ::
* A pointer to the memory object.
*
* cur_size ::
* The current size of the allocated memory block.
*
* new_size ::
* The newly requested size in bytes.
*
* block ::
* The current address of the block in memory.
*
* @Return:
* The address of the reallocated memory block.
*/
FT_CALLBACK_DEF( void* )
ft_realloc( FT_Memory memory,
long cur_size,
long new_size,
void* block )
{
FT_UNUSED( memory );
FT_UNUSED( cur_size );
return ft_srealloc( block, (size_t)new_size );
}
/**************************************************************************
*
* @Function:
* ft_free
*
* @Description:
* The memory release function.
*
* @Input:
* memory ::
* A pointer to the memory object.
*
* block ::
* The address of block in memory to be freed.
*/
FT_CALLBACK_DEF( void )
ft_free( FT_Memory memory,
void* block )
{
FT_UNUSED( memory );
ft_sfree( block );
}
/**************************************************************************
*
* RESOURCE MANAGEMENT INTERFACE
*
*/
#ifndef FT_CONFIG_OPTION_DISABLE_STREAM_SUPPORT
/**************************************************************************
*
* The macro FT_COMPONENT is used in trace mode. It is an implicit
* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log
* messages during execution.
*/
#undef FT_COMPONENT
#define FT_COMPONENT io
/* We use the macro STREAM_FILE for convenience to extract the */
/* system-specific stream handle from a given FreeType stream object */
#define STREAM_FILE( stream ) ( (FT_FILE*)stream->descriptor.pointer )
/**************************************************************************
*
* @Function:
* ft_ansi_stream_close
*
* @Description:
* The function to close a stream.
*
* @Input:
* stream ::
* A pointer to the stream object.
*/
FT_CALLBACK_DEF( void )
ft_ansi_stream_close( FT_Stream stream )
{
ft_fclose( STREAM_FILE( stream ) );
stream->descriptor.pointer = NULL;
stream->size = 0;
stream->base = NULL;
}
/**************************************************************************
*
* @Function:
* ft_ansi_stream_io
*
* @Description:
* The function to open a stream.
*
* @Input:
* stream ::
* A pointer to the stream object.
*
* offset ::
* The position in the data stream to start reading.
*
* buffer ::
* The address of buffer to store the read data.
*
* count ::
* The number of bytes to read from the stream.
*
* @Return:
* The number of bytes actually read. If `count' is zero (that is,
* the function is used for seeking), a non-zero return value
* indicates an error.
*/
FT_CALLBACK_DEF( unsigned long )
ft_ansi_stream_io( FT_Stream stream,
unsigned long offset,
unsigned char* buffer,
unsigned long count )
{
FT_FILE* file;
if ( offset > stream->size && !count )
return 1;
file = STREAM_FILE( stream );
if ( stream->pos != offset )
ft_fseek( file, (long)offset, SEEK_SET );
/* Avoid calling `fread` with `buffer=NULL` and `count=0`, */
/* which is undefined behaviour. */
if ( !count )
return 0;
return (unsigned long)ft_fread( buffer, 1, count, file );
}
/* documentation is in ftstream.h */
FT_BASE_DEF( FT_Error )
FT_Stream_Open( FT_Stream stream,
const char* filepathname )
{
FT_FILE* file;
if ( !stream )
return FT_THROW( Invalid_Stream_Handle );
stream->descriptor.pointer = NULL;
stream->pathname.pointer = (char*)filepathname;
stream->base = NULL;
stream->pos = 0;
stream->read = NULL;
stream->close = NULL;
file = ft_fopen( filepathname, "rb" );
if ( !file )
{
FT_ERROR(( "FT_Stream_Open:"
" could not open `%s'\n", filepathname ));
return FT_THROW( Cannot_Open_Resource );
}
ft_fseek( file, 0, SEEK_END );
stream->size = (unsigned long)ft_ftell( file );
if ( !stream->size )
{
FT_ERROR(( "FT_Stream_Open:" ));
FT_ERROR(( " opened `%s' but zero-sized\n", filepathname ));
ft_fclose( file );
return FT_THROW( Cannot_Open_Stream );
}
ft_fseek( file, 0, SEEK_SET );
stream->descriptor.pointer = file;
stream->read = ft_ansi_stream_io;
stream->close = ft_ansi_stream_close;
FT_TRACE1(( "FT_Stream_Open:" ));
FT_TRACE1(( " opened `%s' (%ld bytes) successfully\n",
filepathname, stream->size ));
return FT_Err_Ok;
}
#endif /* !FT_CONFIG_OPTION_DISABLE_STREAM_SUPPORT */
#ifdef FT_DEBUG_MEMORY
extern FT_Int
ft_mem_debug_init( FT_Memory memory );
extern void
ft_mem_debug_done( FT_Memory memory );
#endif
/* documentation is in ftobjs.h */
FT_BASE_DEF( FT_Memory )
FT_New_Memory( void )
{
FT_Memory memory;
memory = (FT_Memory)ft_smalloc( sizeof ( *memory ) );
if ( memory )
{
memory->user = NULL;
memory->alloc = ft_alloc;
memory->realloc = ft_realloc;
memory->free = ft_free;
#ifdef FT_DEBUG_MEMORY
ft_mem_debug_init( memory );
#endif
}
return memory;
}
/* documentation is in ftobjs.h */
FT_BASE_DEF( void )
FT_Done_Memory( FT_Memory memory )
{
#ifdef FT_DEBUG_MEMORY
ft_mem_debug_done( memory );
#endif
ft_sfree( memory );
}
/* END */