/*
  Copyright (C) 2003, 2004, 2007 GraphicsMagick Group
  Copyright (C) 2002 ImageMagick Studio
  Copyright 1991-1999 E. I. du Pont de Nemours and Company
 
  This program is covered by multiple licenses, which are described in
  Copyright.txt. You should have received a copy of Copyright.txt with this
  package; otherwise see http://www.graphicsmagick.org/www/Copyright.html.
 
  Image Compression/Decompression Methods.
*/
#ifndef _MAGICK_BLOB_H
#define _MAGICK_BLOB_H

#if defined(__cplusplus) || defined(c_plusplus)
extern "C" {
#endif

#include "magick/image.h"

  /*
    Minimum input file size before considering for memory map.
  */
#define MinBlobExtent  32768L

  /*
    Forward declarations.
  */
  typedef struct _BlobInfo BlobInfo;
  
  /*
   *
   * BlobInfo methods
   *
   */

  /*
    Makes a duplicate of the given blob info structure, or if blob info
    is NULL, a new one.
  */
  extern MagickExport BlobInfo* CloneBlobInfo(const BlobInfo *blob_info);

  /*
    Increments the reference count associated with the pixel blob,
    returning a pointer to the blob.
  */
  extern MagickExport BlobInfo* ReferenceBlob(BlobInfo *blob);

  /*
    Deallocate memory associated with the BlobInfo structure.
  */
  extern MagickExport void DestroyBlobInfo(BlobInfo *blob);

  /*
    If BLOB is a memory mapping then unmap it. Reset BlobInfo structure
    to its default state.
  */
  extern MagickExport void DetachBlob(BlobInfo *blob);

  /*
    Initialize a BlobInfo structure.
  */
  extern MagickExport void GetBlobInfo(BlobInfo *blob);

  /*
    Attach memory buffer to a BlobInfo structure.
  */
  extern MagickExport void AttachBlob(BlobInfo *blob_info,
                                      const void *blob,
                                      const size_t length);

  /*
   *
   * Functions for managing a BLOB (type BlobInfo) attached to an Image.
   *
   */

  /*
    Deallocate all memory associated with an Image blob.
  */
  extern MagickExport void DestroyBlob(Image *image);


  /*
   *
   * Formatted image I/O functions
   *
   */

  /*
    Read an Image from a formatted in-memory "file" image  ("BLOB").
  */
  extern MagickExport Image* BlobToImage(const ImageInfo *image_info,
                                         const void *blob,
                                         const size_t length,
                                         ExceptionInfo *exception);

  /*
    Return an Image populated with salient information regarding a
    formatted in-memory "file" image ("BLOB") but without reading the
    image pixels.
  */
  extern MagickExport Image* PingBlob(const ImageInfo *image_info,
                                      const void *blob,
                                      const size_t length,
                                      ExceptionInfo *exception);

  /*
    Writes an Image to a formatted (like a file) in-memory
    representation.
  */
  extern MagickExport void *ImageToBlob(const ImageInfo *image_info,
                                        Image *image,
                                        size_t *length,
                                        ExceptionInfo *exception);

  /*
   *
   * Core File or BLOB I/O functions.
   *
   */

  /*
    Blob open modes.
  */
  typedef enum
    {
      UndefinedBlobMode,    /* Undefined */
      ReadBlobMode,         /* Open for reading (text) */ /* only locale.c */
      ReadBinaryBlobMode,   /* Open for reading (binary) */
      WriteBlobMode,        /* Open for writing (text) */ /* only mvg.c txt.c */
      WriteBinaryBlobMode   /* Open for writing (binary) */
    } BlobMode;

  /*
    Open an input or output stream for access.  May also use a stream
    provided via image_info->stream.
  */
  extern MagickExport MagickPassFail OpenBlob(const ImageInfo *image_info,
                                              Image *image,
                                              const BlobMode mode,
                                              ExceptionInfo *exception);

  /*
    Close I/O to the file or BLOB.
  */
  extern MagickExport void CloseBlob(Image *image);


  /*
    Read data from the file or BLOB into a buffer.
  */
  extern MagickExport size_t ReadBlob(Image *image,
                                      const size_t length,
                                      void *data);

  /*
    Read data from the file or BLOB into a buffer, but support zero-copy
    if possible.
  */
  extern MagickExport size_t ReadBlobZC(Image *image,
                                        const size_t length,
                                        void **data);

  /*
    Write data from a buffer to the file or BLOB.
  */
  extern MagickExport size_t WriteBlob(Image *image,
                                       const size_t length,
                                       const void *data);

  /*
    Move the current read or write offset position in the file or BLOB.
  */
  extern MagickExport magick_off_t SeekBlob(Image *image,
                                            const magick_off_t offset,
                                            const int whence);

  /*
    Obtain the current read or write offset position in the file or
    BLOB.
  */
  extern MagickExport magick_off_t TellBlob(const Image *image);

  /*
    Test to see if EOF has been detected while reading the file or BLOB.
  */
  extern MagickExport int EOFBlob(const Image *image);

  /*
    Test to see if an error has been encountered while doing I/O to the
    file or BLOB.
  */
  extern MagickExport int GetBlobStatus(const Image *image);

  /*
    Obtain the current size of the file or BLOB.  Zero is returned if
    the size can not be determined.
  */
  extern MagickExport magick_off_t GetBlobSize(const Image *image);


  /*
    Obtain the underlying stdio FILE* for the file (if any).
  */
  extern MagickExport FILE *GetBlobFileHandle(const Image *image);

  /*
    Obtain a pointer to the base of where BLOB data is stored.  The data
    is only available if the data is stored on the heap, or is memory
    mapped.  Otherwise NULL is returned.
  */
  extern MagickExport unsigned char *GetBlobStreamData(const Image *image);


  /*
   *
   * Formatted File or BLOB I/O functions.
   *
   */

  /*
    Read a single byte from the file or BLOB.  Returns an EOF character
    if EOF has been detected.
  */
  extern MagickExport int ReadBlobByte(Image *image);

  /*
    Read a 16-bit little-endian unsigned "short" value from the file
    or BLOB.
  */
  extern MagickExport magick_uint16_t ReadBlobLSBShort(Image *image);

  /*
    Read an array of little-endian 16-bit "short" values from the file
    or BLOB.
  */
  extern MagickExport size_t ReadBlobLSBShorts(Image *image, size_t octets,
                                               magick_uint16_t *data);

  /*
    Read a 16-bit big-endian unsigned "short" value from the file or
    BLOB.
  */
  extern MagickExport magick_uint16_t ReadBlobMSBShort(Image *image);

  /*
    Read an array of big-endian 16-bit "short" values from the file or
    BLOB.
  */
  extern MagickExport size_t ReadBlobMSBShorts(Image *image, size_t octets,
                                               magick_uint16_t *data);

  /*
    Read a 32-bit little-endian unsigned "long" value from the file or BLOB.
  */
  extern MagickExport magick_uint32_t ReadBlobLSBLong(Image *image);

  /*
    Read an array of little-endian 32-bit "long" values from the file
    or BLOB.
  */
  extern MagickExport size_t ReadBlobLSBLongs(Image *image, size_t octets,
                                              magick_uint32_t *data);

  /*
    Read a 32-bit big-endian unsigned "long" value from the file or BLOB.
  */
  extern MagickExport magick_uint32_t ReadBlobMSBLong(Image *image);

  /*
    Read an array of big-endian 32-bit "long" values from the file or BLOB.  
  */
  extern MagickExport size_t ReadBlobMSBLongs(Image *image, size_t octets,
                                              magick_uint32_t *data);

  /*
    Read a little-endian 32-bit "float" value from the file or BLOB.
  */
  extern MagickExport float ReadBlobLSBFloat(Image *image);

  /*
    Read an array of little-endian 32-bit "float" values from the file
    or BLOB.
  */
  extern MagickExport size_t ReadBlobLSBFloats(Image *image, size_t octets,
                                               float *data);

  /*
    Read a big-endian 32-bit "float" value from the file or BLOB.
  */
  extern MagickExport float ReadBlobMSBFloat(Image *image);

  /*
    Read an array of big-endian 32-bit "float" values from the file or
    BLOB.
  */
  extern MagickExport size_t ReadBlobMSBFloats(Image *image, size_t octets,
                                               float *data);

  /*
    Read a little-endian 64-bit "double" value from the file or BLOB.
  */
  extern MagickExport double ReadBlobLSBDouble(Image *image);

  /*
    Read an array of little-endian 64-bit "double" values from the
    file or BLOB.
  */
  extern MagickExport size_t ReadBlobLSBDoubles(Image *image, size_t octets,
                                                double *data);

  /*
    Read a big-endian 64-bit "double" value from the file or BLOB.
  */
  extern MagickExport double ReadBlobMSBDouble(Image *image);

  /*
    Read an array of big-endian 64-bit "double" values from the file or BLOB.
  */
  extern MagickExport size_t ReadBlobMSBDoubles(Image *image, size_t octets,
                                                double *data);

  /*
    Read a string from the file or blob until a newline character is
    read or an end-of-file condition is encountered.
  */
  extern MagickExport char *ReadBlobString(Image *image,
                                           char *string);

  /*
    Write a single byte to the file or BLOB.
  */
  extern MagickExport size_t WriteBlobByte(Image *image,
                                           const magick_uint8_t value);

  /*
    Write the content of an entire disk file to the file or BLOB.
  */
  extern MagickExport MagickPassFail WriteBlobFile(Image *image,
                                                   const char *filename);

  /*
    Write a 16-bit "short" value to the  file or BLOB in little-endian order.
  */
  extern MagickExport size_t WriteBlobLSBShort(Image *image,
                                               const magick_uint16_t value);

  /*
    Write a 32-bit "long" value to the file or BLOB in little-endian order.
  */
  extern MagickExport size_t WriteBlobLSBLong(Image *image,
                                              const magick_uint32_t value);



  /*
    Write a 32-bit "long" value to the file or BLOB in big-endian order.
  */
  extern MagickExport size_t WriteBlobMSBLong(Image *image,
                                              const magick_uint32_t value);

  /*
    Write a 16-bit "short" value to the file or BLOB in big-endian order.
  */
  extern MagickExport size_t WriteBlobMSBShort(Image *image,
                                               const magick_uint16_t value);

  /*
    Write a C string to the file or BLOB, without the terminating NULL
    byte.
  */
  extern MagickExport size_t WriteBlobString(Image *image,
                                             const char *string);

  /*
   *
   * BLOB attribute access.
   *
   */

  /*
    Blob supports seek operations.  BlobSeek() and BlobTell() may safely
    be used.
  */
  extern MagickExport MagickBool BlobIsSeekable(const Image *image);

  /*
    Allow file descriptor to be closed (if True).
  */
  extern MagickExport void SetBlobClosable(Image *image,
                                           MagickBool closable);

  /*
    Blob is for a temporary file which should be deleted (if True).
  */
  extern MagickExport void SetBlobTemporary(Image *image,
                                            MagickBool isTemporary);

  /*
    Returns MagickTrue if the file associated with the blob is a temporary
    file and should be removed when the associated image is destroyed.
  */
  extern MagickExport MagickBool GetBlobTemporary(const Image *image);

  /*
   *
   * Memory mapped file support.
   *
   */

  /*
    Memory mapping modes.
  */
  typedef enum
    {
      ReadMode,             /* Map for read-only access */
      WriteMode,            /* Map for write-only access (useless) */
      IOMode                /* Map for read/write access */
    } MapMode;

  /*
    Release memory mapping for a region.
  */
  extern MagickExport MagickPassFail UnmapBlob(void *map,
                                               const size_t length);

  /*
    Perform a requested memory mapping of a file descriptor.
  */
  extern MagickExport void *MapBlob(int file,
                                    const MapMode mode,
                                    magick_off_t offset,
                                    size_t length);

  /*
   *
   * Buffer to File / File to Buffer functions.
   *
   */

  /*
    Writes a buffer to a named file.
  */
  extern MagickExport MagickPassFail BlobToFile(const char *filename,
                                                const void *blob,
                                                const size_t length,
                                                ExceptionInfo *exception);

  /*
    Read the contents of a file into memory.
  */
  extern MagickExport void *FileToBlob(const char *filename,
                                       size_t *length,
                                       ExceptionInfo *exception);

  /*
   *
   * Junk yet to be categorized.
   *
   */

  /*
    Reserve space for a specified output size.
  */
  extern MagickExport MagickPassFail BlobReserveSize(Image *image, magick_off_t size);

  /*
    Copies data from the input stream to a file.  Useful in case it is
    necessary to perform seek operations on the input data.
  */
  extern MagickExport MagickPassFail ImageToFile(Image *image,
                                                 const char *filename,
                                                 ExceptionInfo *exception);

  /*
    Search for a configuration file (".mgk" file) using appropriate
    rules and return as an in-memory buffer.
  */
  extern MagickExport void *GetConfigureBlob(const char *filename,
                                             char *path,
                                             size_t *length,
                                             ExceptionInfo *exception);

  /*
    Converts a least-significant byte first buffer of integers to
    most-significant byte first.
  */
  extern MagickExport void MSBOrderLong(unsigned char *buffer,
                                        const size_t length);

  /*
    Converts a least-significant byte first buffer of integers to
    most-significant byte first.
  */
  extern MagickExport void MSBOrderShort(unsigned char *p,
                                         const size_t length);


#if defined(__cplusplus) || defined(c_plusplus)
}
#endif

#endif

/*
 * Local Variables:
 * mode: c
 * c-basic-offset: 2
 * fill-column: 78
 * End:
 */
