102 lines
2.1 KiB
C++
102 lines
2.1 KiB
C++
#ifndef __HASH_H
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#define __HASH_H
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#include <string>
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#include "util.hh"
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using namespace std;
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struct Hash
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{
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static const unsigned int hashSize = 16;
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unsigned char hash[hashSize];
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/* Create a zeroed hash object. */
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Hash();
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/* Check whether two hash are equal. */
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bool operator == (Hash & h2);
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/* Check whether two hash are not equal. */
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bool operator != (Hash & h2);
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/* Convert a hash code into a hexadecimal representation. */
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operator string() const;
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};
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class BadRefError : public Error
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{
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public:
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BadRefError(string _err) : Error(_err) { };
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};
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/* Parse a hexadecimal representation of a hash code. */
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Hash parseHash(const string & s);
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/* Verify that the given string is a valid hash code. */
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bool isHash(const string & s);
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/* Compute the hash of the given string. */
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Hash hashString(const string & s);
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/* Compute the hash of the given file. */
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Hash hashFile(const string & fileName);
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/* Compute the hash of the given path. The hash is defined as
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follows:
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hash(path) = md5(dump(path))
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*/
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Hash hashPath(const string & path);
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/* Dump a path as follows:
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IF path points to a REGULAR FILE:
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dump(path) = attrs(
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[ ("type", "regular")
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, ("contents", contents(path))
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])
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IF path points to a DIRECTORY:
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dump(path) = attrs(
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[ ("type", "directory")
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, ("entries", concat(map(f, sort(entries(path)))))
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])
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where f(fn) = attrs(
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[ ("name", fn)
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, ("file", dump(path + "/" + fn))
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])
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where:
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attrs(as) = concat(map(attr, as)) + encN(0)
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attrs((a, b)) = encS(a) + encS(b)
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encS(s) = encN(len(s)) + s + (padding until next 64-bit boundary)
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encN(n) = 64-bit little-endian encoding of n.
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contents(path) = the contents of a regular file.
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sort(strings) = lexicographic sort by 8-bit value (strcmp).
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entries(path) = the entries of a directory, without `.' and
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`..'.
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`+' denotes string concatenation. */
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struct DumpSink
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{
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virtual void operator () (const unsigned char * data, unsigned int len) = 0;
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};
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void dumpPath(const string & path, DumpSink & sink);
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#endif /* !__HASH_H */
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