View file File name : hardware.h Content :/** * \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;