/***************************************************************************/

/*                                                                         */

/*  ftsystem.c                                                             */

/*                                                                         */

/*    Unix-specific FreeType low-level system interface (body).            */

/*                                                                         */

/*  Copyright 1996-2001, 2002, 2004, 2005, 2006, 2007, 2008 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.                                        */

/*                                                                         */

/***************************************************************************/





#include <ft2build.h>

  /* we use our special ftconfig.h file, not the standard one */

#include <ftconfig.h>

#include FT_INTERNAL_DEBUG_H

#include FT_SYSTEM_H

#include FT_ERRORS_H

#include FT_TYPES_H

#include FT_INTERNAL_STREAM_H



  /* memory-mapping includes and definitions */

#ifdef HAVE_UNISTD_H

#include <unistd.h>

#endif



#include <sys/mman.h>

#ifndef MAP_FILE

#define MAP_FILE  0x00

#endif



#ifdef MUNMAP_USES_VOIDP

#define MUNMAP_ARG_CAST  void *

#else

#define MUNMAP_ARG_CAST  char *

#endif



#ifdef NEED_MUNMAP_DECL



#ifdef __cplusplus

  extern "C"

#else

  extern

#endif

  int

  munmap( char*  addr,

          int    len );



#define MUNMAP_ARG_CAST  char *



#endif /* NEED_DECLARATION_MUNMAP */





#include <sys/types.h>

#include <sys/stat.h>



#ifdef HAVE_FCNTL_H

#include <fcntl.h>

#endif



#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <errno.h>





  /*************************************************************************/

  /*                                                                       */

  /*                       MEMORY MANAGEMENT INTERFACE                     */

  /*                                                                       */

  /*************************************************************************/





  /*************************************************************************/

  /*                                                                       */

  /* <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 malloc( 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 realloc( block, 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 );



    free( block );

  }





  /*************************************************************************/

  /*                                                                       */

  /*                     RESOURCE MANAGEMENT INTERFACE                     */

  /*                                                                       */

  /*************************************************************************/





  /*************************************************************************/

  /*                                                                       */

  /* 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  trace_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 )  ( (FILE*)stream->descriptor.pointer )





  /*************************************************************************/

  /*                                                                       */

  /* <Function>                                                            */

  /*    ft_close_stream_by_munmap                                          */

  /*                                                                       */

  /* <Description>                                                         */

  /*    The function to close a stream which is opened by mmap.            */

  /*                                                                       */

  /* <Input>                                                               */

  /*    stream :: A pointer to the stream object.                          */

  /*                                                                       */

  FT_CALLBACK_DEF( void )

  ft_close_stream_by_munmap( FT_Stream  stream )

  {

    munmap( (MUNMAP_ARG_CAST)stream->descriptor.pointer, stream->size );



    stream->descriptor.pointer = NULL;

    stream->size               = 0;

    stream->base               = 0;

  }





  /*************************************************************************/

  /*                                                                       */

  /* <Function>                                                            */

  /*    ft_close_stream_by_free                                            */

  /*                                                                       */

  /* <Description>                                                         */

  /*    The function to close a stream which is created by ft_alloc.       */

  /*                                                                       */

  /* <Input>                                                               */

  /*    stream :: A pointer to the stream object.                          */

  /*                                                                       */

  FT_CALLBACK_DEF( void )

  ft_close_stream_by_free( FT_Stream  stream )

  {

    ft_free( NULL, stream->descriptor.pointer );



    stream->descriptor.pointer = NULL;

    stream->size               = 0;

    stream->base               = 0;

  }





  /* documentation is in ftobjs.h */



  FT_BASE_DEF( FT_Error )

  FT_Stream_Open( FT_Stream    stream,

                  const char*  filepathname )

  {

    int          file;

    struct stat  stat_buf;





    if ( !stream )

      return FT_Err_Invalid_Stream_Handle;



    /* open the file */

    file = open( filepathname, O_RDONLY );

    if ( file < 0 )

    {

      FT_ERROR(( "FT_Stream_Open:" ));

      FT_ERROR(( " could not open `%s'\n", filepathname ));

      return FT_Err_Cannot_Open_Resource;

    }



    /* Here we ensure that a "fork" will _not_ duplicate   */

    /* our opened input streams on Unix.  This is critical */

    /* since it avoids some (possible) access control      */

    /* issues and cleans up the kernel file table a bit.   */

    /*                                                     */

#ifdef F_SETFD

#ifdef FD_CLOEXEC

    (void)fcntl( file, F_SETFD, FD_CLOEXEC );

#else

    (void)fcntl( file, F_SETFD, 1 );

#endif /* FD_CLOEXEC */

#endif /* F_SETFD */



    if ( fstat( file, &stat_buf ) < 0 )

    {

      FT_ERROR(( "FT_Stream_Open:" ));

      FT_ERROR(( " could not `fstat' file `%s'\n", filepathname ));

      goto Fail_Map;

    }



    /* XXX: TODO -- real 64bit platform support                        */

    /*                                                                 */

    /* `stream->size' is typedef'd to unsigned long (in                */

    /* freetype/ftsystem.h); `stat_buf.st_size', however, is usually   */

    /* typedef'd to off_t (in sys/stat.h).                             */

    /* On some platforms, the former is 32bit and the latter is 64bit. */

    /* To avoid overflow caused by fonts in huge files larger than     */

    /* 2GB, do a test.  Temporary fix proposed by Sean McBride.        */

    /*                                                                 */

    if ( stat_buf.st_size > LONG_MAX )

    {

      FT_ERROR(( "FT_Stream_Open: file is too big\n" ));

      goto Fail_Map;

    }

    else if ( stat_buf.st_size == 0 )

    {

      FT_ERROR(( "FT_Stream_Open: zero-length file\n" ));

      goto Fail_Map;

    }



    /* This cast potentially truncates a 64bit to 32bit! */

    stream->size = (unsigned long)stat_buf.st_size;

    stream->pos  = 0;

    stream->base = (unsigned char *)mmap( NULL,

                                          stream->size,

                                          PROT_READ,

                                          MAP_FILE | MAP_PRIVATE,

                                          file,

                                          0 );



    /* on some RTOS, mmap might return 0 */

    if ( (long)stream->base != -1 && stream->base != NULL )

      stream->close = ft_close_stream_by_munmap;

    else

    {

      ssize_t  total_read_count;





      FT_ERROR(( "FT_Stream_Open:" ));

      FT_ERROR(( " could not `mmap' file `%s'\n", filepathname ));



      stream->base = (unsigned char*)ft_alloc( NULL, stream->size );



      if ( !stream->base )

      {

        FT_ERROR(( "FT_Stream_Open:" ));

        FT_ERROR(( " could not `alloc' memory\n" ));

        goto Fail_Map;

      }



      total_read_count = 0;

      do {

        ssize_t  read_count;





        read_count = read( file,

                           stream->base + total_read_count,

                           stream->size - total_read_count );



        if ( read_count <= 0 )

        {

          if ( read_count == -1 && errno == EINTR )

            continue;



          FT_ERROR(( "FT_Stream_Open:" ));

          FT_ERROR(( " error while `read'ing file `%s'\n", filepathname ));

          goto Fail_Read;

        }



        total_read_count += read_count;



      } while ( (unsigned long)total_read_count != stream->size );



      stream->close = ft_close_stream_by_free;

    }



    close( file );



    stream->descriptor.pointer = stream->base;

    stream->pathname.pointer   = (char*)filepathname;



    stream->read = 0;



    FT_TRACE1(( "FT_Stream_Open:" ));

    FT_TRACE1(( " opened `%s' (%d bytes) successfully\n",

                filepathname, stream->size ));



    return FT_Err_Ok;



  Fail_Read:

    ft_free( NULL, stream->base );



  Fail_Map:

    close( file );



    stream->base = NULL;

    stream->size = 0;

    stream->pos  = 0;



    return FT_Err_Cannot_Open_Stream;

  }





#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)malloc( sizeof ( *memory ) );

    if ( memory )

    {

      memory->user    = 0;

      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

    memory->free( memory, memory );

  }





/* END */

