mercurial/bitmanipulation.h
author Matt Harbison <matt_harbison@yahoo.com>
Thu, 23 May 2019 22:50:11 -0400
branchstable
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child 46707 eed42f1c22d6
permissions -rw-r--r--
manifest: add some documentation to _lazymanifest python code It was not particularly easy figuring out the design of this class and keeping track of how the pieces work. So might as well write some of it down for the next person.
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#ifndef _HG_BITMANIPULATION_H_
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#define _HG_BITMANIPULATION_H_
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#include <string.h>
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#include "compat.h"
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static inline uint32_t getbe32(const char *c)
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{
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	const unsigned char *d = (const unsigned char *)c;
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	return ((((uint32_t)d[0]) << 24) | (((uint32_t)d[1]) << 16) |
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	        (((uint32_t)d[2]) << 8) | (d[3]));
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}
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static inline int16_t getbeint16(const char *c)
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{
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	const unsigned char *d = (const unsigned char *)c;
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	return ((d[0] << 8) | (d[1]));
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}
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static inline uint16_t getbeuint16(const char *c)
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{
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	const unsigned char *d = (const unsigned char *)c;
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	return ((d[0] << 8) | (d[1]));
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}
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static inline void putbe32(uint32_t x, char *c)
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{
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	c[0] = (x >> 24) & 0xff;
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	c[1] = (x >> 16) & 0xff;
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	c[2] = (x >> 8) & 0xff;
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	c[3] = (x)&0xff;
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}
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static inline double getbefloat64(const char *c)
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{
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	const unsigned char *d = (const unsigned char *)c;
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	double ret;
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	int i;
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	uint64_t t = 0;
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	for (i = 0; i < 8; i++) {
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		t = (t << 8) + d[i];
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	}
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	memcpy(&ret, &t, sizeof(t));
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	return ret;
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}
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#endif