64 lines
2.6 KiB
C
64 lines
2.6 KiB
C
/**
|
|
* \file lzma/hardware.h
|
|
* \brief Hardware information
|
|
*
|
|
* Since liblzma can consume a lot of system resources, it also provides
|
|
* ways to limit the resource usage. Applications linking against liblzma
|
|
* need to do the actual decisions how much resources to let liblzma to use.
|
|
* To ease making these decisions, liblzma provides functions to find out
|
|
* the relevant capabilities of the underlaying hardware. Currently there
|
|
* is only a function to find out the amount of RAM, but in the future there
|
|
* will be also a function to detect how many concurrent threads the system
|
|
* can run.
|
|
*
|
|
* \note On some operating systems, these function may temporarily
|
|
* load a shared library or open file descriptor(s) to find out
|
|
* the requested hardware information. Unless the application
|
|
* assumes that specific file descriptors are not touched by
|
|
* other threads, this should have no effect on thread safety.
|
|
* Possible operations involving file descriptors will restart
|
|
* the syscalls if they return EINTR.
|
|
*/
|
|
|
|
/*
|
|
* Author: Lasse Collin
|
|
*
|
|
* This file has been put into the public domain.
|
|
* You can do whatever you want with this file.
|
|
*
|
|
* See ../lzma.h for information about liblzma as a whole.
|
|
*/
|
|
|
|
#ifndef LZMA_H_INTERNAL
|
|
# error Never include this file directly. Use <lzma.h> instead.
|
|
#endif
|
|
|
|
|
|
/**
|
|
* \brief Get the total amount of physical memory (RAM) in bytes
|
|
*
|
|
* This function may be useful when determining a reasonable memory
|
|
* usage limit for decompressing or how much memory it is OK to use
|
|
* for compressing.
|
|
*
|
|
* \return On success, the total amount of physical memory in bytes
|
|
* is returned. If the amount of RAM cannot be determined,
|
|
* zero is returned. This can happen if an error occurs
|
|
* or if there is no code in liblzma to detect the amount
|
|
* of RAM on the specific operating system.
|
|
*/
|
|
extern LZMA_API(uint64_t) lzma_physmem(void) lzma_nothrow;
|
|
|
|
|
|
/**
|
|
* \brief Get the number of processor cores or threads
|
|
*
|
|
* This function may be useful when determining how many threads to use.
|
|
* If the hardware supports more than one thread per CPU core, the number
|
|
* of hardware threads is returned if that information is available.
|
|
*
|
|
* \brief On success, the number of available CPU threads or cores is
|
|
* returned. If this information isn't available or an error
|
|
* occurs, zero is returned.
|
|
*/
|
|
extern LZMA_API(uint32_t) lzma_cputhreads(void) lzma_nothrow;
|