lix/src/libutil/hash.cc
2005-01-13 15:44:44 +00:00

129 lines
2.5 KiB
C++

#include <iostream>
extern "C" {
#include "md5.h"
}
#include "hash.hh"
#include "archive.hh"
Hash::Hash(HashType type)
{
this->type = type;
if (type == htMD5) hashSize = md5HashSize;
else if (type == htSHA1) hashSize = sha1HashSize;
memset(hash, 0, hashSize);
}
bool Hash::operator == (const Hash & h2) const
{
if (hashSize != h2.hashSize) return false;
for (unsigned int i = 0; i < hashSize; i++)
if (hash[i] != h2.hash[i]) return false;
return true;
}
bool Hash::operator != (const Hash & h2) const
{
return !(*this == h2);
}
bool Hash::operator < (const Hash & h) const
{
for (unsigned int i = 0; i < hashSize; i++) {
if (hash[i] < h.hash[i]) return true;
if (hash[i] > h.hash[i]) return false;
}
return false;
}
Hash::operator string() const
{
ostringstream str;
for (unsigned int i = 0; i < hashSize; i++) {
str.fill('0');
str.width(2);
str << hex << (int) hash[i];
}
return str.str();
}
Hash parseHash(const string & s)
{
Hash hash(htMD5);
if (s.length() != hash.hashSize * 2)
throw Error(format("invalid hash `%1%'") % s);
for (unsigned int i = 0; i < hash.hashSize; i++) {
string s2(s, i * 2, 2);
if (!isxdigit(s2[0]) || !isxdigit(s2[1]))
throw Error(format("invalid hash `%1%'") % s);
istringstream str(s2);
int n;
str >> hex >> n;
hash.hash[i] = n;
}
return hash;
}
bool isHash(const string & s)
{
if (s.length() != 32) return false;
for (int i = 0; i < 32; i++) {
char c = s[i];
if (!((c >= '0' && c <= '9') ||
(c >= 'a' && c <= 'f')))
return false;
}
return true;
}
Hash hashString(const string & s)
{
Hash hash(htMD5);
md5_buffer(s.c_str(), s.length(), hash.hash);
return hash;
}
Hash hashFile(const Path & path)
{
Hash hash(htMD5);
FILE * file = fopen(path.c_str(), "rb");
if (!file)
throw SysError(format("file `%1%' does not exist") % path);
int err = md5_stream(file, hash.hash);
fclose(file);
if (err) throw SysError(format("cannot hash file `%1%'") % path);
return hash;
}
struct HashSink : DumpSink
{
struct md5_ctx ctx;
virtual void operator ()
(const unsigned char * data, unsigned int len)
{
md5_process_bytes(data, len, &ctx);
}
};
Hash hashPath(const Path & path)
{
Hash hash(htMD5);
HashSink sink;
md5_init_ctx(&sink.ctx);
dumpPath(path, sink);
md5_finish_ctx(&sink.ctx, hash.hash);
return hash;
}