misc/libfreetype/src/gzip/ftgzip.c
changeset 5172 88f2e05288ba
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/misc/libfreetype/src/gzip/ftgzip.c	Mon Apr 25 01:46:54 2011 +0200
@@ -0,0 +1,688 @@
+/***************************************************************************/
+/*                                                                         */
+/*  ftgzip.c                                                               */
+/*                                                                         */
+/*    FreeType support for .gz compressed files.                           */
+/*                                                                         */
+/*  This optional component relies on zlib.  It should mainly be used to   */
+/*  parse compressed PCF fonts, as found with many X11 server              */
+/*  distributions.                                                         */
+/*                                                                         */
+/*  Copyright 2002-2006, 2009-2011 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>
+#include FT_INTERNAL_MEMORY_H
+#include FT_INTERNAL_STREAM_H
+#include FT_INTERNAL_DEBUG_H
+#include FT_GZIP_H
+#include FT_CONFIG_STANDARD_LIBRARY_H
+
+
+#include FT_MODULE_ERRORS_H
+
+#undef __FTERRORS_H__
+
+#define FT_ERR_PREFIX  Gzip_Err_
+#define FT_ERR_BASE    FT_Mod_Err_Gzip
+
+#include FT_ERRORS_H
+
+
+#ifdef FT_CONFIG_OPTION_USE_ZLIB
+
+#ifdef FT_CONFIG_OPTION_PIC
+#error "gzip code does not support PIC yet"
+#endif 
+
+#ifdef FT_CONFIG_OPTION_SYSTEM_ZLIB
+
+#include <zlib.h>
+
+#else /* !FT_CONFIG_OPTION_SYSTEM_ZLIB */
+
+ /* In this case, we include our own modified sources of the ZLib    */
+ /* within the "ftgzip" component.  The modifications were necessary */
+ /* to #include all files without conflicts, as well as preventing   */
+ /* the definition of "extern" functions that may cause linking      */
+ /* conflicts when a program is linked with both FreeType and the    */
+ /* original ZLib.                                                   */
+
+#define NO_DUMMY_DECL
+#ifndef USE_ZLIB_ZCALLOC
+#define MY_ZCALLOC /* prevent all zcalloc() & zfree() in zutils.c */
+#endif
+
+#include "zlib.h"
+
+#undef  SLOW
+#define SLOW  1  /* we can't use asm-optimized sources here! */
+
+  /* Urgh.  `inflate_mask' must not be declared twice -- C++ doesn't like
+     this.  We temporarily disable it and load all necessary header files. */
+#define NO_INFLATE_MASK
+#include "zutil.h"
+#include "inftrees.h"
+#include "infblock.h"
+#include "infcodes.h"
+#include "infutil.h"
+#undef  NO_INFLATE_MASK
+
+  /* infutil.c must be included before infcodes.c */
+#include "zutil.c"
+#include "inftrees.c"
+#include "infutil.c"
+#include "infcodes.c"
+#include "infblock.c"
+#include "inflate.c"
+#include "adler32.c"
+
+#endif /* !FT_CONFIG_OPTION_SYSTEM_ZLIB */
+
+
+/***************************************************************************/
+/***************************************************************************/
+/*****                                                                 *****/
+/*****            Z L I B   M E M O R Y   M A N A G E M E N T          *****/
+/*****                                                                 *****/
+/***************************************************************************/
+/***************************************************************************/
+
+  /* it is better to use FreeType memory routines instead of raw
+     'malloc/free' */
+
+  static voidpf
+  ft_gzip_alloc( FT_Memory  memory,
+                 uInt       items,
+                 uInt       size )
+  {
+    FT_ULong    sz = (FT_ULong)size * items;
+    FT_Error    error;
+    FT_Pointer  p  = NULL;
+
+
+    (void)FT_ALLOC( p, sz );
+    return p;
+  }
+
+
+  static void
+  ft_gzip_free( FT_Memory  memory,
+                voidpf     address )
+  {
+    FT_MEM_FREE( address );
+  }
+
+
+#if !defined( FT_CONFIG_OPTION_SYSTEM_ZLIB ) && !defined( USE_ZLIB_ZCALLOC )
+
+  local voidpf
+  zcalloc ( voidpf    opaque,
+            unsigned  items,
+            unsigned  size )
+  {
+    return ft_gzip_alloc( (FT_Memory)opaque, items, size );
+  }
+
+  local void
+  zcfree( voidpf  opaque,
+          voidpf  ptr )
+  {
+    ft_gzip_free( (FT_Memory)opaque, ptr );
+  }
+
+#endif /* !SYSTEM_ZLIB && !USE_ZLIB_ZCALLOC */
+
+
+/***************************************************************************/
+/***************************************************************************/
+/*****                                                                 *****/
+/*****               Z L I B   F I L E   D E S C R I P T O R           *****/
+/*****                                                                 *****/
+/***************************************************************************/
+/***************************************************************************/
+
+#define FT_GZIP_BUFFER_SIZE  4096
+
+  typedef struct  FT_GZipFileRec_
+  {
+    FT_Stream  source;         /* parent/source stream        */
+    FT_Stream  stream;         /* embedding stream            */
+    FT_Memory  memory;         /* memory allocator            */
+    z_stream   zstream;        /* zlib input stream           */
+
+    FT_ULong   start;          /* starting position, after .gz header */
+    FT_Byte    input[FT_GZIP_BUFFER_SIZE];   /* input read buffer  */
+
+    FT_Byte    buffer[FT_GZIP_BUFFER_SIZE];  /* output buffer      */
+    FT_ULong   pos;                          /* position in output */
+    FT_Byte*   cursor;
+    FT_Byte*   limit;
+
+  } FT_GZipFileRec, *FT_GZipFile;
+
+
+  /* gzip flag byte */
+#define FT_GZIP_ASCII_FLAG   0x01 /* bit 0 set: file probably ascii text */
+#define FT_GZIP_HEAD_CRC     0x02 /* bit 1 set: header CRC present */
+#define FT_GZIP_EXTRA_FIELD  0x04 /* bit 2 set: extra field present */
+#define FT_GZIP_ORIG_NAME    0x08 /* bit 3 set: original file name present */
+#define FT_GZIP_COMMENT      0x10 /* bit 4 set: file comment present */
+#define FT_GZIP_RESERVED     0xE0 /* bits 5..7: reserved */
+
+
+  /* check and skip .gz header - we don't support `transparent' compression */
+  static FT_Error
+  ft_gzip_check_header( FT_Stream  stream )
+  {
+    FT_Error  error;
+    FT_Byte   head[4];
+
+
+    if ( FT_STREAM_SEEK( 0 )       ||
+         FT_STREAM_READ( head, 4 ) )
+      goto Exit;
+
+    /* head[0] && head[1] are the magic numbers;    */
+    /* head[2] is the method, and head[3] the flags */
+    if ( head[0] != 0x1f              ||
+         head[1] != 0x8b              ||
+         head[2] != Z_DEFLATED        ||
+        (head[3] & FT_GZIP_RESERVED)  )
+    {
+      error = Gzip_Err_Invalid_File_Format;
+      goto Exit;
+    }
+
+    /* skip time, xflags and os code */
+    (void)FT_STREAM_SKIP( 6 );
+
+    /* skip the extra field */
+    if ( head[3] & FT_GZIP_EXTRA_FIELD )
+    {
+      FT_UInt  len;
+
+
+      if ( FT_READ_USHORT_LE( len ) ||
+           FT_STREAM_SKIP( len )    )
+        goto Exit;
+    }
+
+    /* skip original file name */
+    if ( head[3] & FT_GZIP_ORIG_NAME )
+      for (;;)
+      {
+        FT_UInt  c;
+
+
+        if ( FT_READ_BYTE( c ) )
+          goto Exit;
+
+        if ( c == 0 )
+          break;
+      }
+
+    /* skip .gz comment */
+    if ( head[3] & FT_GZIP_COMMENT )
+      for (;;)
+      {
+        FT_UInt  c;
+
+
+        if ( FT_READ_BYTE( c ) )
+          goto Exit;
+
+        if ( c == 0 )
+          break;
+      }
+
+    /* skip CRC */
+    if ( head[3] & FT_GZIP_HEAD_CRC )
+      if ( FT_STREAM_SKIP( 2 ) )
+        goto Exit;
+
+  Exit:
+    return error;
+  }
+
+
+  static FT_Error
+  ft_gzip_file_init( FT_GZipFile  zip,
+                     FT_Stream    stream,
+                     FT_Stream    source )
+  {
+    z_stream*  zstream = &zip->zstream;
+    FT_Error   error   = Gzip_Err_Ok;
+
+
+    zip->stream = stream;
+    zip->source = source;
+    zip->memory = stream->memory;
+
+    zip->limit  = zip->buffer + FT_GZIP_BUFFER_SIZE;
+    zip->cursor = zip->limit;
+    zip->pos    = 0;
+
+    /* check and skip .gz header */
+    {
+      stream = source;
+
+      error = ft_gzip_check_header( stream );
+      if ( error )
+        goto Exit;
+
+      zip->start = FT_STREAM_POS();
+    }
+
+    /* initialize zlib -- there is no zlib header in the compressed stream */
+    zstream->zalloc = (alloc_func)ft_gzip_alloc;
+    zstream->zfree  = (free_func) ft_gzip_free;
+    zstream->opaque = stream->memory;
+
+    zstream->avail_in = 0;
+    zstream->next_in  = zip->buffer;
+
+    if ( inflateInit2( zstream, -MAX_WBITS ) != Z_OK ||
+         zstream->next_in == NULL                     )
+      error = Gzip_Err_Invalid_File_Format;
+
+  Exit:
+    return error;
+  }
+
+
+  static void
+  ft_gzip_file_done( FT_GZipFile  zip )
+  {
+    z_stream*  zstream = &zip->zstream;
+
+
+    inflateEnd( zstream );
+
+    /* clear the rest */
+    zstream->zalloc    = NULL;
+    zstream->zfree     = NULL;
+    zstream->opaque    = NULL;
+    zstream->next_in   = NULL;
+    zstream->next_out  = NULL;
+    zstream->avail_in  = 0;
+    zstream->avail_out = 0;
+
+    zip->memory = NULL;
+    zip->source = NULL;
+    zip->stream = NULL;
+  }
+
+
+  static FT_Error
+  ft_gzip_file_reset( FT_GZipFile  zip )
+  {
+    FT_Stream  stream = zip->source;
+    FT_Error   error;
+
+
+    if ( !FT_STREAM_SEEK( zip->start ) )
+    {
+      z_stream*  zstream = &zip->zstream;
+
+
+      inflateReset( zstream );
+
+      zstream->avail_in  = 0;
+      zstream->next_in   = zip->input;
+      zstream->avail_out = 0;
+      zstream->next_out  = zip->buffer;
+
+      zip->limit  = zip->buffer + FT_GZIP_BUFFER_SIZE;
+      zip->cursor = zip->limit;
+      zip->pos    = 0;
+    }
+
+    return error;
+  }
+
+
+  static FT_Error
+  ft_gzip_file_fill_input( FT_GZipFile  zip )
+  {
+    z_stream*  zstream = &zip->zstream;
+    FT_Stream  stream  = zip->source;
+    FT_ULong   size;
+
+
+    if ( stream->read )
+    {
+      size = stream->read( stream, stream->pos, zip->input,
+                           FT_GZIP_BUFFER_SIZE );
+      if ( size == 0 )
+        return Gzip_Err_Invalid_Stream_Operation;
+    }
+    else
+    {
+      size = stream->size - stream->pos;
+      if ( size > FT_GZIP_BUFFER_SIZE )
+        size = FT_GZIP_BUFFER_SIZE;
+
+      if ( size == 0 )
+        return Gzip_Err_Invalid_Stream_Operation;
+
+      FT_MEM_COPY( zip->input, stream->base + stream->pos, size );
+    }
+    stream->pos += size;
+
+    zstream->next_in  = zip->input;
+    zstream->avail_in = size;
+
+    return Gzip_Err_Ok;
+  }
+
+
+  static FT_Error
+  ft_gzip_file_fill_output( FT_GZipFile  zip )
+  {
+    z_stream*  zstream = &zip->zstream;
+    FT_Error   error   = Gzip_Err_Ok;
+
+
+    zip->cursor        = zip->buffer;
+    zstream->next_out  = zip->cursor;
+    zstream->avail_out = FT_GZIP_BUFFER_SIZE;
+
+    while ( zstream->avail_out > 0 )
+    {
+      int  err;
+
+
+      if ( zstream->avail_in == 0 )
+      {
+        error = ft_gzip_file_fill_input( zip );
+        if ( error )
+          break;
+      }
+
+      err = inflate( zstream, Z_NO_FLUSH );
+
+      if ( err == Z_STREAM_END )
+      {
+        zip->limit = zstream->next_out;
+        if ( zip->limit == zip->cursor )
+          error = Gzip_Err_Invalid_Stream_Operation;
+        break;
+      }
+      else if ( err != Z_OK )
+      {
+        error = Gzip_Err_Invalid_Stream_Operation;
+        break;
+      }
+    }
+
+    return error;
+  }
+
+
+  /* fill output buffer; `count' must be <= FT_GZIP_BUFFER_SIZE */
+  static FT_Error
+  ft_gzip_file_skip_output( FT_GZipFile  zip,
+                            FT_ULong     count )
+  {
+    FT_Error  error = Gzip_Err_Ok;
+    FT_ULong  delta;
+
+
+    for (;;)
+    {
+      delta = (FT_ULong)( zip->limit - zip->cursor );
+      if ( delta >= count )
+        delta = count;
+
+      zip->cursor += delta;
+      zip->pos    += delta;
+
+      count -= delta;
+      if ( count == 0 )
+        break;
+
+      error = ft_gzip_file_fill_output( zip );
+      if ( error )
+        break;
+    }
+
+    return error;
+  }
+
+
+  static FT_ULong
+  ft_gzip_file_io( FT_GZipFile  zip,
+                   FT_ULong     pos,
+                   FT_Byte*     buffer,
+                   FT_ULong     count )
+  {
+    FT_ULong  result = 0;
+    FT_Error  error;
+
+
+    /* Reset inflate stream if we're seeking backwards.        */
+    /* Yes, that is not too efficient, but it saves memory :-) */
+    if ( pos < zip->pos )
+    {
+      error = ft_gzip_file_reset( zip );
+      if ( error )
+        goto Exit;
+    }
+
+    /* skip unwanted bytes */
+    if ( pos > zip->pos )
+    {
+      error = ft_gzip_file_skip_output( zip, (FT_ULong)( pos - zip->pos ) );
+      if ( error )
+        goto Exit;
+    }
+
+    if ( count == 0 )
+      goto Exit;
+
+    /* now read the data */
+    for (;;)
+    {
+      FT_ULong  delta;
+
+
+      delta = (FT_ULong)( zip->limit - zip->cursor );
+      if ( delta >= count )
+        delta = count;
+
+      FT_MEM_COPY( buffer, zip->cursor, delta );
+      buffer      += delta;
+      result      += delta;
+      zip->cursor += delta;
+      zip->pos    += delta;
+
+      count -= delta;
+      if ( count == 0 )
+        break;
+
+      error = ft_gzip_file_fill_output( zip );
+      if ( error )
+        break;
+    }
+
+  Exit:
+    return result;
+  }
+
+
+/***************************************************************************/
+/***************************************************************************/
+/*****                                                                 *****/
+/*****               G Z   E M B E D D I N G   S T R E A M             *****/
+/*****                                                                 *****/
+/***************************************************************************/
+/***************************************************************************/
+
+  static void
+  ft_gzip_stream_close( FT_Stream  stream )
+  {
+    FT_GZipFile  zip    = (FT_GZipFile)stream->descriptor.pointer;
+    FT_Memory    memory = stream->memory;
+
+
+    if ( zip )
+    {
+      /* finalize gzip file descriptor */
+      ft_gzip_file_done( zip );
+
+      FT_FREE( zip );
+
+      stream->descriptor.pointer = NULL;
+    }
+  }
+
+
+  static FT_ULong
+  ft_gzip_stream_io( FT_Stream  stream,
+                     FT_ULong   pos,
+                     FT_Byte*   buffer,
+                     FT_ULong   count )
+  {
+    FT_GZipFile  zip = (FT_GZipFile)stream->descriptor.pointer;
+
+
+    return ft_gzip_file_io( zip, pos, buffer, count );
+  }
+
+
+  static FT_ULong
+  ft_gzip_get_uncompressed_size( FT_Stream  stream )
+  {
+    FT_Error  error;
+    FT_ULong  old_pos;
+    FT_ULong  result = 0;
+
+
+    old_pos = stream->pos;
+    if ( !FT_Stream_Seek( stream, stream->size - 4 ) )
+    {
+      result = FT_Stream_ReadULong( stream, &error );
+      if ( error )
+        result = 0;
+
+      (void)FT_Stream_Seek( stream, old_pos );
+    }
+
+    return result;
+  }
+
+
+  FT_EXPORT_DEF( FT_Error )
+  FT_Stream_OpenGzip( FT_Stream  stream,
+                      FT_Stream  source )
+  {
+    FT_Error     error;
+    FT_Memory    memory = source->memory;
+    FT_GZipFile  zip;
+
+
+    /*
+     *  check the header right now; this prevents allocating un-necessary
+     *  objects when we don't need them
+     */
+    error = ft_gzip_check_header( source );
+    if ( error )
+      goto Exit;
+
+    FT_ZERO( stream );
+    stream->memory = memory;
+
+    if ( !FT_QNEW( zip ) )
+    {
+      error = ft_gzip_file_init( zip, stream, source );
+      if ( error )
+      {
+        FT_FREE( zip );
+        goto Exit;
+      }
+
+      stream->descriptor.pointer = zip;
+    }
+
+    /*
+     *  We use the following trick to try to dramatically improve the
+     *  performance while dealing with small files.  If the original stream
+     *  size is less than a certain threshold, we try to load the whole font
+     *  file into memory.  This saves us from using the 32KB buffer needed
+     *  to inflate the file, plus the two 4KB intermediate input/output
+     *  buffers used in the `FT_GZipFile' structure.
+     */
+    {
+      FT_ULong  zip_size = ft_gzip_get_uncompressed_size( source );
+
+
+      if ( zip_size != 0 && zip_size < 40 * 1024 )
+      {
+        FT_Byte*  zip_buff;
+
+
+        if ( !FT_ALLOC( zip_buff, zip_size ) )
+        {
+          FT_ULong  count;
+
+
+          count = ft_gzip_file_io( zip, 0, zip_buff, zip_size );
+          if ( count == zip_size )
+          {
+            ft_gzip_file_done( zip );
+            FT_FREE( zip );
+
+            stream->descriptor.pointer = NULL;
+
+            stream->size  = zip_size;
+            stream->pos   = 0;
+            stream->base  = zip_buff;
+            stream->read  = NULL;
+            stream->close = ft_gzip_stream_close;
+
+            goto Exit;
+          }
+
+          ft_gzip_file_io( zip, 0, NULL, 0 );
+          FT_FREE( zip_buff );
+        }
+        error = Gzip_Err_Ok;
+      }
+    }
+
+    stream->size  = 0x7FFFFFFFL;  /* don't know the real size! */
+    stream->pos   = 0;
+    stream->base  = 0;
+    stream->read  = ft_gzip_stream_io;
+    stream->close = ft_gzip_stream_close;
+
+  Exit:
+    return error;
+  }
+
+#else  /* !FT_CONFIG_OPTION_USE_ZLIB */
+
+  FT_EXPORT_DEF( FT_Error )
+  FT_Stream_OpenGzip( FT_Stream  stream,
+                      FT_Stream  source )
+  {
+    FT_UNUSED( stream );
+    FT_UNUSED( source );
+
+    return Gzip_Err_Unimplemented_Feature;
+  }
+
+#endif /* !FT_CONFIG_OPTION_USE_ZLIB */
+
+
+/* END */