iup-stack/im/include/im_binfile.h

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8.5 KiB
C++
Executable File

/** \file
* \brief Binary File Access.
*
* See Copyright Notice in im_lib.h
*/
#include "im_util.h"
#ifndef __IM_BINFILE_H
#define __IM_BINFILE_H
#if defined(__cplusplus)
extern "C" {
#endif
/** \defgroup binfile Binary File Access
*
* \par
* These functions are very useful for reading/writing binary files
* that have headers or data that have to be converted depending on
* the current CPU byte order. It can invert 2, 4 or 8 bytes numbers to/from little/big-endian orders.
* \par
* It will process the data only if the file format is different from the current CPU.
* \par
* Can read from disk or memory. In case of a memory buffer, the file name must be the \ref imBinMemoryFileName structure.
* \par
* See \ref im_binfile.h
* \ingroup util */
/** \brief Binary File Structure (Private).
* \ingroup binfile */
typedef struct _imBinFile imBinFile;
/** Opens an existant binary file for reading.
* The default file byte order is the CPU byte order.
* Returns NULL if failed.
* \ingroup binfile */
imBinFile* imBinFileOpen(const char* pFileName);
/** Creates a new binary file for writing.
* The default file byte order is the CPU byte order.
* Returns NULL if failed.
* \ingroup binfile */
imBinFile* imBinFileNew(const char* pFileName);
/** Closes the file.
* \ingroup binfile */
void imBinFileClose(imBinFile* bfile);
/** Indicates that was an error on the last operation.
* \ingroup binfile */
int imBinFileError(imBinFile* bfile);
/** Returns the file size in bytes.
* \ingroup binfile */
unsigned long imBinFileSize(imBinFile* bfile);
/** Changes the file byte order. Returns the old one.
* \ingroup binfile */
int imBinFileByteOrder(imBinFile* bfile, int pByteOrder);
/** Reads an array of count values with byte sizes: 1, 2, 4, or 8. And invert the byte order if necessary after read. \n
* Returns the actual count of values read.
* \ingroup binfile */
unsigned long imBinFileRead(imBinFile* bfile, void* pValues, unsigned long pCount, int pSizeOf);
/** Writes an array of values with sizes: 1, 2, 4, or 8. And invert the byte order if necessary before write.\n
* <b>ATENTION</b>: The function will not make a temporary copy of the values to invert the byte order.\n
* So after the call the values will be invalid, if the file byte order is different from the CPU byte order. \n
* Returns the actual count of values written.
* \ingroup binfile */
unsigned long imBinFileWrite(imBinFile* bfile, void* pValues, unsigned long pCount, int pSizeOf);
/** Writes a string without the NULL terminator. The function uses sprintf to compose the string. \n
* The internal buffer is fixed at 10240 bytes. \n
* Returns the actual count of values written.
* \ingroup binfile */
unsigned long imBinFilePrintf(imBinFile* bfile, const char *format, ...);
/** Reads a line until line break. \n
* Returns the line in array, must have room enough. Line break is discarded. \n
* Use *size to inform buffer size. *size return the actual number os characters read.
* \ingroup binfile */
int imBinFileReadLine(imBinFile* handle, char* comment, int *size);
/** Skips a line, including line break.
* \ingroup binfile */
int imBinFileSkipLine(imBinFile* handle);
/** Reads an integer number from the current position until found a non integer character.
* Returns a non zero value if successful.
* \ingroup binfile */
int imBinFileReadInteger(imBinFile* handle, int *value);
/** Reads an floating point number from the current position until found a non number character.
* Returns a non zero value if successful.
* \ingroup binfile */
int imBinFileReadReal(imBinFile* handle, double *value);
/** Moves the file pointer from the beginning of the file.\n
* When writing to a file seeking can go beyond the end of the file.
* \ingroup binfile */
void imBinFileSeekTo(imBinFile* bfile, unsigned long pOffset);
/** Moves the file pointer from current position.\n
* If the offset is a negative value the pointer moves backwards.
* \ingroup binfile */
void imBinFileSeekOffset(imBinFile* bfile, long pOffset);
/** Moves the file pointer from the end of the file.\n
* The offset is usually a negative value.
* \ingroup binfile */
void imBinFileSeekFrom(imBinFile* bfile, long pOffset);
/** Returns the current offset position.
* \ingroup binfile */
unsigned long imBinFileTell(imBinFile* bfile);
/** Indicates that the file pointer is at the end of the file.
* \ingroup binfile */
int imBinFileEndOfFile(imBinFile* bfile);
/** Predefined I/O Modules.
* \ingroup binfile */
enum imBinFileModule
{
IM_RAWFILE, /**< System dependent file I/O Routines. */
IM_STREAM, /**< Standard Ansi C Stream I/O Routines. */
IM_MEMFILE, /**< Uses a memory buffer (see \ref imBinMemoryFileName). */
IM_SUBFILE, /**< It is a sub file. FileName is a imBinFile* pointer from any other module. */
IM_FILEHANDLE,/**< System dependent file I/O Routines, but FileName is a system file handle ("int" in UNIX and "HANDLE" in Windows). */
IM_IOCUSTOM0 /**< Other registered modules starts from here. */
};
/** Sets the current I/O module.
* \returns the previous function set, or -1 if failed.
* See also \ref imBinFileModule.
* \ingroup binfile */
int imBinFileSetCurrentModule(int pModule);
/** \brief Memory File Filename Parameter Structure
*
* \par
* Fake file name for the memory I/O module.
* \ingroup binfile */
typedef struct _imBinMemoryFileName
{
unsigned char *buffer; /**< The memory buffer. If you are reading the buffer must exists.
* If you are writing the buffer can be internally allocated to the given size. The buffer is never free.
* The buffer is allocated using "malloc", and reallocated using "realloc". Use "free" to release it.
* To avoid RTL conflicts use the function imBinMemoryRelease. */
int size; /**< Size of the buffer. */
float reallocate; /**< Reallocate factor for the memory buffer when writing (size += reallocate*size).
* Set reallocate to 0 to disable reallocation, in this case buffer must not be NULL. */
}imBinMemoryFileName;
/** Release the internal memory allocated when writing a Memory File (see \ref imBinMemoryFileName).
* \ingroup binfile */
void imBinMemoryRelease(unsigned char *buffer);
#if defined(__cplusplus)
}
#endif
#if defined(__cplusplus)
/** \brief Binary File I/O Base Class
*
* Base class to help the creation of new modules.\n
* It handles the read/write operations with byte order correction if necessary.
* \ingroup binfile */
class imBinFileBase
{
friend class imBinSubFile;
protected:
int IsNew,
FileByteOrder,
DoByteOrder; // to speed up byte order checking
// These will actually read/write the data
virtual unsigned long ReadBuf(void* pValues, unsigned long pSize) = 0;
virtual unsigned long WriteBuf(void* pValues, unsigned long pSize) = 0;
void SetByteOrder(int ByteOrder)
{
this->FileByteOrder = ByteOrder;
if (ByteOrder != imBinCPUByteOrder())
this->DoByteOrder = 1;
else
this->DoByteOrder = 0;
}
public:
virtual ~imBinFileBase(){};
int InitByteOrder(int ByteOrder)
{
int old_byte_order = this->FileByteOrder;
if (ByteOrder == IM_LITTLEENDIAN ||
ByteOrder == IM_BIGENDIAN)
SetByteOrder(ByteOrder);
return old_byte_order;
}
// These will take care of byte swap if needed.
unsigned long Read(void* pValues, unsigned long pCount, int pSizeOf)
{
unsigned long rSize = ReadBuf(pValues, pCount * pSizeOf);
if (pSizeOf != 1 && DoByteOrder) imBinSwapBytes(pValues, pCount, pSizeOf);
return rSize/pSizeOf;
}
unsigned long Write(void* pValues, unsigned long pCount, int pSizeOf)
{
if (pSizeOf != 1 && DoByteOrder) imBinSwapBytes(pValues, pCount, pSizeOf);
return WriteBuf(pValues, pCount * pSizeOf)/pSizeOf;
}
virtual void Open(const char* pFileName) = 0;
virtual void New(const char* pFileName) = 0;
virtual void Close() = 0;
virtual unsigned long FileSize() = 0;
virtual int HasError() const = 0;
virtual void SeekTo(unsigned long pOffset) = 0;
virtual void SeekOffset(long pOffset) = 0;
virtual void SeekFrom(long pOffset) = 0;
virtual unsigned long Tell() const = 0;
virtual int EndOfFile() const = 0;
};
/** File I/O module creation callback.
* \ingroup binfile */
typedef imBinFileBase* (*imBinFileNewFunc)();
/** Register a user I/O module.\n
* Returns the new function set id.\n
* Accepts up to 10 modules.
* \ingroup binfile */
extern "C" int imBinFileRegisterModule(imBinFileNewFunc pNewFunc);
#endif
#endif