DynBuffer Struct Reference

Detailed Description

A dynamic buffer.

You either Subclass and implement the DynBuffer_OnAllocError method or set OnAllocError to NULL.

#include <DynBuffer.h>

Inheritance diagram for DynBuffer:

Public Member Functions
	DynBuffer (int startSize, int expandSize, AllocatorIntf *alloc=0, DynBuffer_OnAllocError onAllocError=0)
	Create a dynamic buffer. More...
	~DynBuffer ()
	destructor. More...
void	release ()
	terminate the internal dynamic buffer by calling free
char *	getBuf ()
	Returns a pointer to the internal buffer. More...
U32	getBufSize ()
	Returns current size of internal formatted data.
int	getECode ()
	Returns the error code if memory allocation failed. More...
int	expand (int sizeNeeded)
	force buffer to expand. More...
char *	getCurPtr ()
	Return a pointer to the internal cursor position in the internal dynamic buffer. More...
void	incrementCursor (int nBytes)
	Increments the internal cursor position. More...
Public Member Functions inherited from BufPrint
	BufPrint (void *userData=0, BufPrint_Flush flush=0)
	BufPrint constructor. More...
	BufPrint (char *buf, int size, void *userData=0, BufPrint_Flush flush=0)
	BufPrint constructor. More...
void *	getUserData ()
	Returns the user data pointer set in the constructor.
int	vprintf (const char *fmt, va_list argList)
	The printf function's format is identical to the standard ANSI vprintf function. More...
int	printf (const char *fmt,...)
	The printf function's format is identical to the standard ANSI printf function, but with the following extensions: More...
int	baputc (int c)
	print character (wrapper for BufPrint_putc)
int	write (const void *data, int len)
	Write data to the buffer. More...
int	write (const char *buf)
	Used for sending a zero terminated string to the client. More...
void	setBuf (char *buf, int size)
	Set the buffer used by BufPrint. More...
char *	getBuf ()
	Returns a pointer to the internal buffer. More...
U32	getBufSize ()
	Returns current size of internal formatted data.
void	erase ()
	resets the cursor, thus erasing the data in the buffer
int	flush ()
	Flush buffer.
int	b64Encode (const void *data, S32 slen)
	Encode binary data as Base64. More...
int	b64urlEncode (const void *source, S32 slen, bool padding)
	Encode binary data as Base64url. More...
int	jsonString (const char *str)
	Print and escape a string such that a browser can run the JavaScript 'eval' function and produce a string identical to the string the 'str' argument points to. More...

Static Public Member Functions
static const char *	ecode2str (int eCode)
	Convert error code to string. More...

Constructor & Destructor Documentation

DynBuffer()

DynBuffer::DynBuffer	(	int	startSize,
		int	expandSize,
		AllocatorIntf *	alloc = 0,
		DynBuffer_OnAllocError	onAllocError = 0
	)

Create a dynamic buffer.

Parameters

startSize	the size allocated by calling malloc.
expandSize	chunk size used when calling realloc. Set to 0 if you do not want the buffer to dynamically grow.
alloc	the allocator used by the dynamic buffer.
onAllocError	pointer to function called on allocation error.

~DynBuffer()

DynBuffer::~DynBuffer

(

)

destructor.

release memory by calling method DynBuffer::release.

Member Function Documentation

ecode2str()

const char * DynBuffer::ecode2str ( int  eCode )

static

Convert error code to string.

Used by the onAllocError callback.

expand()

int DynBuffer::expand

(

int

sizeNeeded

)

force buffer to expand.

Parameters

sizeNeeded

the required expand size.

Returns

0 on success. A non zero value is returned if it is not enough memory to expand the buffer i.e. if the AllocatorIntf provided in the constructor cannot re-allocate the buffer.

getBuf()

char * DynBuffer::getBuf

(

)

Returns a pointer to the internal buffer.

This pointer is invalid after the DynBuffer reallocates the internal buffer. Unlike the BufPrint::getBuf method, the buffer returned by this method is zero terminated.

getCurPtr()

char * DynBuffer::getCurPtr

(

)

Return a pointer to the internal cursor position in the internal dynamic buffer.

See also

expand incrementCursor

getECode()

int DynBuffer::getECode

(

)

Returns the error code if memory allocation failed.

This method is typically used when the DynBuffer_OnAllocError is set to NULL in the constructor.

 0: No error.
-1: No allocator.
-2: Malloc failed.
-3: Need to realloc buffer, but no realloc provided.
-4: Realloc failed.
-5: Buffer too large.

incrementCursor()

void DynBuffer::incrementCursor

(

int

nBytes

)

Increments the internal cursor position.

It is possible to manually format data in the internal buffer. This method advances the internal cursor by N bytes.

example

char data[]={"My data"};
if(myBuf->expand(sizeof(data)-1) == 0) // -1: no need to store null term.
{
   memcpy(myBuf->getCurPtr(), data, sizeof(data)-1);
   myBuf->incrementCursor(sizeof(data)-1);