General read/write operations
[Global/general functions]

Data Structures

• struct _MG_RWops

Defines

• #define MGUI_RWseek(ctx, offset, whence)   (ctx)->seek(ctx, offset, whence)

  Seeks an MG_RWops object.
  

• #define MGUI_RWtell(ctx)   (ctx)->seek(ctx, 0, SEEK_CUR)

  Obtains the current value of the position indicator for a data source.
  

• #define MGUI_RWread(ctx, ptr, size, n)   (ctx)->read(ctx, ptr, size, n)

  Reads data blocks from a data source.
  

• #define MGUI_RWwrite(ctx, ptr, size, n)   (ctx)->write(ctx, ptr, size, n)

  Writes data blocks to a data source.
  

• #define MGUI_RWclose(ctx)   (ctx)->close(ctx)

  Closes an MG_RWops object.
  

• #define MGUI_RWeof(ctx)   (ctx)->eof(ctx)

  Tests the end-of-file indicator for an data source.
  

Typedefs

• typedef _MG_RWops MG_RWops

Functions

• MG_EXPORT MG_RWops * MGUI_RWFromFile (const char *file, const char *mode)

  Creates an MG_RWops object from a file.
  

• MG_EXPORT MG_RWops * MGUI_RWFromFP (FILE *fp, int autoclose)

  Creates an MG_RWops object from an opened stdio FILE object.
  

• MG_EXPORT MG_RWops * MGUI_RWFromMem (void *mem, int size)

  Creates an MG_RWops object from a block of memory.
  

• MG_EXPORT void MGUI_InitMemRW (MG_RWops *area, void *mem, int size)

  Initializes an MG_RWops object from a block of memory.
  

• MG_EXPORT MG_RWops * MGUI_AllocRW (void)

  Allocates an uninitialized MG_RWops object.
  

• MG_EXPORT void MGUI_FreeRW (MG_RWops *area)

  Frees an MG_RWops object.
  

• MG_EXPORT int MGUI_RWgetc (MG_RWops *area)

  Reads the next character from an data source.
  

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Detailed Description

MiniGUI's general read/write operation provides a general interface to read from and write to various data source, such as files, memory, and so on.

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Define Documentation

#define MGUI_RWclose (  ctx   )     (ctx)->close(ctx)

Closes an MG_RWops object. This macro close the MG_RWops object pointed to by ctx. Parameters: ctx  The pointer to the MG_RWops object. Returns: Upon successful completion 0 is returned, otherwise non-zero on error. See also: MGUI_RWread Definition at line 312 of file endianrw.h.

#define MGUI_RWeof (  ctx   )     (ctx)->eof(ctx)

Tests the end-of-file indicator for an data source. This macro tests the end-of-file indicator for the data source pointed to by ctx. Parameters: ctx  The pointer to the MG_RWops object. Returns: Non-zero if end-of-file indicator is set. See also: MGUI_RWtell Definition at line 327 of file endianrw.h.

#define MGUI_RWread (  ctx, ptr, size, n   )     (ctx)->read(ctx, ptr, size, n)

Reads data blocks from a data source. This macro reads up to n objects each of size size from the data source ctx to the area pointed to by ptr. Parameters: ctx  The pointer to the MG_RWops object. ptr  The buffer will save the data read. size  The size of each object. n  The number of objects to be read. Returns: The number of objects read, or -1 if the read failed. See also: MGUI_RWwrite Definition at line 280 of file endianrw.h.

#define MGUI_RWseek (  ctx, offset, whence   )     (ctx)->seek(ctx, offset, whence)

Seeks an MG_RWops object. This macro seeks to offset relative to whence. Parameters: ctx  The pointer to the MG_RWops object. offset  The offset relative to whence. whence  One of stdio's whence values: SEEK_SET the offset is relative to the start of the file. SEEK_CUR the offset is relative to the current position indicator. SEEK_END the offset is relative to the end of the file. Returns: The final offset in the data source. See also: MGUI_RWtell Definition at line 248 of file endianrw.h.

#define MGUI_RWtell (  ctx   )     (ctx)->seek(ctx, 0, SEEK_CUR)

Obtains the current value of the position indicator for a data source. This macro obtains the current value of the position indicator for the data source pointed to by ctx. Parameters: ctx  The pointer to the MG_RWops object. Returns: The current value of the position indicator. See also: MGUI_RWseek Definition at line 263 of file endianrw.h.

#define MGUI_RWwrite (  ctx, ptr, size, n   )     (ctx)->write(ctx, ptr, size, n)

Writes data blocks to a data source. This macro writes exactly n objects each of size size from the area pointed to by ptr to the data source ctx. Parameters: ctx  The pointer to the MG_RWops object. ptr  The buffer contains the data to be written. size  The size of each object. n  The number of objects to be written. Returns: The number written, or -1 if the write failed. See also: MGUI_RWread Definition at line 297 of file endianrw.h.

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Typedef Documentation

typedef struct _MG_RWops MG_RWops

The read/write operation structure.

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Function Documentation

MG_RWops * MGUI_AllocRW (  void   )

Allocates an uninitialized MG_RWops object. This function allocates an uninitialized MG_RWops object. You can specify the fields of the structure, and implemente a customized MG_RWops object. Returns: The pointer to allocated MG_RWops structure, NULL indicates error. See also: MG_RWops

void MGUI_FreeRW (  MG_RWops *  area  )

Frees an MG_RWops object. This function frees the MG_RWops object pointed to by area. Parameters: area  The pointer to the MG_RWops object. See also: MGUI_RWFromFile, MGUI_RWFromFP, MGUI_RWFromMem

void MGUI_InitMemRW (  MG_RWops *  area, void *  mem, int  size )

Initializes an MG_RWops object from a block of memory. This function initializes an MG_RWops object pointed to by area from a block of memory pointed to by mem, which is size bytes long. Parameters: area  The pointer to the MG_RWops object. mem  The pointer to the memory block. size  The size of the memory block. Returns: None. See also: MG_RWops, MGUI_FreeRW, MGUI_RWFromMem

MG_RWops * MGUI_RWFromFile (  const char *  file, const char *  mode )

Creates an MG_RWops object from a file. This function uses the mode specified by mode and opens the file file by using stdio function fopen. If success, this function creates a MG_RWops object and returns it. Parameters: file  The file name. mode  The mode will be passed to fopen. Returns: The pointer to created MG_RWops structure, NULL indicates error. See also: MG_RWops, MGUI_RWFromFP, MGUI_FreeRW, fopen(3)

MG_RWops * MGUI_RWFromFP (  FILE *  fp, int  autoclose )

Creates an MG_RWops object from an opened stdio FILE object. This function uses an opened stdio FILE object fp to create a MG_RWops object. Parameters: fp  The opened stdio FILE object. autoclose  Indicates whether to close the FILE object when close method is called. Returns: The pointer to created MG_RWops structure, NULL indicates error. See also: MG_RWops, MGUI_RWFromFile, MGUI_FreeRW

MG_RWops * MGUI_RWFromMem (  void *  mem, int  size )

Creates an MG_RWops object from a block of memory. This function creates an MG_RWops object from a block of memory pointed to by mem, which is size bytes long. Parameters: mem  The pointer to the memory block. size  The size of the memory block. Returns: The pointer to created MG_RWops structure, NULL indicates error. See also: MG_RWops, MGUI_FreeRW

int MGUI_RWgetc (  MG_RWops *  area  )

Reads the next character from an data source. This function reads the next character from the data source pointed to by area, and returns it as an unsigned char cast to an int, or EOF on end of file or error. Parameters: area  The pointer to the MG_RWops object. Returns: The character read, EOF indicates end-of-file or error. See also: MGUI_RWread

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