system.h File Reference

Prototypes for BSPACM system enhancements to newlib. More...

#include <bspacm/core.h>
#include <unistd.h>

Go to the source code of this file.

Functions
void *	_sbrk (intptr_t increment)
void *	_bspacm_sbrk_error (void *brk, ptrdiff_t current, ptrdiff_t increment)

Detailed Description

Prototypes for BSPACM system enhancements to newlib.

Homepage

http://github.com/pabigot/bspacm

Copyright

Copyright 2014, Peter A. Bigot. Licensed under BSD-3-Clause

Function Documentation

void* _bspacm_sbrk_error	(	void *	brk,
		ptrdiff_t	current,
		ptrdiff_t	increment
	)

This function is invoked whenever _sbrk() runs out of memory.

libbspacm.a provides a weak definition is that disables interrupts and enters an infinite loop, allowing diagnosis through a debugger. The application may provide an alternative implementation that is more diagnostic or that returns the responsibility of handling out-of-memory to the application (i.e. requires the application to check allocation return values).

Parameters

brk	the current program break
current	total number of bytes allocated by previous successful invocations of _sbrk() (i.e., allocated bytes preceding brk)
increment	the number of bytes in the request that _sbrk() cannot satisfy

Returns

This implementation does not return. If superseded, an implementation that does return must set errno to ENOMEM and return (void*)-1.

void* _sbrk

(

intptr_t

increment

)

The system function used to allocate memory for use by libc heap memory management.

Heap Management documents how to select a specific _sbrk() implementation from among the available policies by which allocation is done, and how to supply your own implementation.

Note

All BSPACM policies invoke _bspacm_sbrk_error() if allocation fails, allowing an application to control response to the failure.

Parameters

increment

the number of bytes of additional memory that libc needs in order to perform additional allocations.

Returns

a pointer to the new end-of-memory, or (void*)-1 if no allocation can be performed.