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