upstream/mercurial-mirror Files · mercurial/bitmanipulation.h

merge: fix race that could cause wrong size in dirstate...

merge: fix race that could cause wrong size in dirstate The problem is that hg merge/update/etc work the following way: 1. figure out what files to update 2. apply the update to disk 3. apply the update to in-memory dirstate 4. write dirstate where step3 looks at the filesystem and assumes it sees the result of step2. If a file is changed between step2 and step3, step3 will record incorrect information in the dirstate. I avoid this by passing the size step3 needs directly from step2, for the common path (not implemented for change/delete conflicts for instance). I didn't fix the same race for the exec bit for now, because it's less likely to be problematic and I had trouble due to the fact that the dirstate stores the permissions differently from the manifest (st_mode vs '' 'l' 'x'), in combination with tests that pretend that symlinks are not supported. However, I moved the lstat from step3 to step2, which should tighten the race window markedly, both for the exec bit and for the mtime. Differential Revision: https://phab.mercurial-scm.org/D6475

Augie Fackler - - Load All Authors

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        Maciej Fijalkowski
    
internals: move the bitmanipulation routines into its own file...

              r29444
            
      #ifndef _HG_BITMANIPULATION_H_

      #define _HG_BITMANIPULATION_H_

        Martin von Zweigbergk
    
bitmanipulation: add missing include of string.h...

              r32646
            
      #include <string.h>

        Maciej Fijalkowski
    
internals: move the bitmanipulation routines into its own file...

              r29444
            
      #include "compat.h"

      static inline uint32_t getbe32(const char *c)

      {

      	const unsigned char *d = (const unsigned char *)c;

        Augie Fackler
    
bitmanipulation: fix undefined behavior in bit shift in getbe32...

              r38322
            
      	return ((((uint32_t)d[0]) << 24) | (((uint32_t)d[1]) << 16) |

      	        (((uint32_t)d[2]) << 8) | (d[3]));

        Maciej Fijalkowski
    
internals: move the bitmanipulation routines into its own file...

              r29444
            
      }

      static inline int16_t getbeint16(const char *c)

      {

      	const unsigned char *d = (const unsigned char *)c;

        Augie Fackler
    
bitmanipulation: reformat with clang-format...

              r34698
            
      	return ((d[0] << 8) | (d[1]));

        Maciej Fijalkowski
    
internals: move the bitmanipulation routines into its own file...

              r29444
            
      }

      static inline uint16_t getbeuint16(const char *c)

      {

      	const unsigned char *d = (const unsigned char *)c;

        Augie Fackler
    
bitmanipulation: reformat with clang-format...

              r34698
            
      	return ((d[0] << 8) | (d[1]));

        Maciej Fijalkowski
    
internals: move the bitmanipulation routines into its own file...

              r29444
            
      }

      static inline void putbe32(uint32_t x, char *c)

      {

      	c[0] = (x >> 24) & 0xff;

      	c[1] = (x >> 16) & 0xff;

      	c[2] = (x >> 8) & 0xff;

        Augie Fackler
    
bitmanipulation: reformat with clang-format...

              r34698
            
      	c[3] = (x)&0xff;

        Maciej Fijalkowski
    
internals: move the bitmanipulation routines into its own file...

              r29444
            
      }

      static inline double getbefloat64(const char *c)

      {

      	const unsigned char *d = (const unsigned char *)c;

      	double ret;

      	int i;

      	uint64_t t = 0;

      	for (i = 0; i < 8; i++) {

        Augie Fackler
    
bitmanipulation: reformat with clang-format...

              r34698
            
      		t = (t << 8) + d[i];

        Maciej Fijalkowski
    
internals: move the bitmanipulation routines into its own file...

              r29444
            
      	}

      	memcpy(&ret, &t, sizeof(t));

      	return ret;

      }

      #endif

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Maciej Fijalkowski internals: move the bitmanipulation routines into its own file...	r29444	#ifndef _HG_BITMANIPULATION_H_
		#define _HG_BITMANIPULATION_H_

Martin von Zweigbergk bitmanipulation: add missing include of string.h...	r32646	#include <string.h>

Maciej Fijalkowski internals: move the bitmanipulation routines into its own file...	r29444	#include "compat.h"

		static inline uint32_t getbe32(const char *c)
		{
		const unsigned char d = (const unsigned char )c;

Augie Fackler bitmanipulation: fix undefined behavior in bit shift in getbe32...	r38322	return ((((uint32_t)d[0]) << 24) \| (((uint32_t)d[1]) << 16) \|
		(((uint32_t)d[2]) << 8) \| (d[3]));
Maciej Fijalkowski internals: move the bitmanipulation routines into its own file...	r29444	}

		static inline int16_t getbeint16(const char *c)
		{
		const unsigned char d = (const unsigned char )c;

Augie Fackler bitmanipulation: reformat with clang-format...	r34698	return ((d[0] << 8) \| (d[1]));
Maciej Fijalkowski internals: move the bitmanipulation routines into its own file...	r29444	}

		static inline uint16_t getbeuint16(const char *c)
		{
		const unsigned char d = (const unsigned char )c;

Augie Fackler bitmanipulation: reformat with clang-format...	r34698	return ((d[0] << 8) \| (d[1]));
Maciej Fijalkowski internals: move the bitmanipulation routines into its own file...	r29444	}

		static inline void putbe32(uint32_t x, char *c)
		{
		c[0] = (x >> 24) & 0xff;
		c[1] = (x >> 16) & 0xff;
		c[2] = (x >> 8) & 0xff;
Augie Fackler bitmanipulation: reformat with clang-format...	r34698	c[3] = (x)&0xff;
Maciej Fijalkowski internals: move the bitmanipulation routines into its own file...	r29444	}

		static inline double getbefloat64(const char *c)
		{
		const unsigned char d = (const unsigned char )c;
		double ret;
		int i;
		uint64_t t = 0;
		for (i = 0; i < 8; i++) {
Augie Fackler bitmanipulation: reformat with clang-format...	r34698	t = (t << 8) + d[i];
Maciej Fijalkowski internals: move the bitmanipulation routines into its own file...	r29444	}
		memcpy(&ret, &t, sizeof(t));
		return ret;
		}

		#endif