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-rw-r--r--lzip.h79
1 files changed, 36 insertions, 43 deletions
diff --git a/lzip.h b/lzip.h
index 7cb9927..2138056 100644
--- a/lzip.h
+++ b/lzip.h
@@ -32,7 +32,7 @@ class State
public:
enum { states = 12 };
State() throw() : st( 0 ) {}
- int operator()() const throw() { return st; }
+ unsigned char operator()() const throw() { return st; }
bool is_char() const throw() { return st < 7; }
void set_char() throw()
@@ -118,7 +118,7 @@ public:
{
unsigned int c = n;
for( int k = 0; k < 8; ++k )
- { if( c & 1 ) c = 0xEDB88320 ^ ( c >> 1 ); else c >>= 1; }
+ { if( c & 1 ) c = 0xEDB88320U ^ ( c >> 1 ); else c >>= 1; }
data[n] = c;
}
}
@@ -133,29 +133,27 @@ public:
}
};
-extern const CRC32 crc32;
+namespace Lzlib_namespace { extern const CRC32 crc32; }
+using Lzlib_namespace::crc32;
const uint8_t magic_string[4] = { 'L', 'Z', 'I', 'P' };
struct File_header
{
- uint8_t magic[4];
- uint8_t version;
- uint8_t coded_dict_size;
+ uint8_t data[6]; // 0-3 magic bytes
+ // 4 version
+ // 5 coded_dict_size
+ enum { size = 6 };
void set_magic() throw()
- { std::memcpy( magic, magic_string, sizeof magic ); version = 1; }
+ { std::memcpy( data, magic_string, 4 ); data[4] = 1; }
bool verify_magic() const throw()
- {
- return ( std::memcmp( magic, magic_string, sizeof magic ) == 0 );
- }
+ { return ( std::memcmp( data, magic_string, 4 ) == 0 ); }
- bool verify_version() const throw()
- {
- return ( version <= 1 );
- }
+ uint8_t version() const throw() { return data[4]; }
+ bool verify_version() const throw() { return ( data[4] <= 1 ); }
bool verify() const throw()
{
@@ -174,24 +172,24 @@ struct File_header
int dictionary_size() const throw()
{
- int size = ( 1 << ( coded_dict_size & 0x1F ) );
- if( size > min_dictionary_size && size <= max_dictionary_size )
- size -= ( size / 16 ) * ( ( coded_dict_size >> 5 ) & 0x07 );
- return size;
+ int sz = ( 1 << ( data[5] & 0x1F ) );
+ if( sz > min_dictionary_size && sz <= max_dictionary_size )
+ sz -= ( sz / 16 ) * ( ( data[5] >> 5 ) & 0x07 );
+ return sz;
}
- bool dictionary_size( const int size ) throw()
+ bool dictionary_size( const int sz ) throw()
{
- if( size >= min_dictionary_size && size <= max_dictionary_size )
+ if( sz >= min_dictionary_size && sz <= max_dictionary_size )
{
- coded_dict_size = real_bits( size - 1 );
- if( size > min_dictionary_size )
+ data[5] = real_bits( sz - 1 );
+ if( sz > min_dictionary_size )
{
- const int base_size = 1 << coded_dict_size;
+ const int base_size = 1 << data[5];
const int wedge = base_size / 16;
for( int i = 7; i >= 1; --i )
- if( base_size - ( i * wedge ) >= size )
- { coded_dict_size |= ( i << 5 ); break; }
+ if( base_size - ( i * wedge ) >= sz )
+ { data[5] |= ( i << 5 ); break; }
}
return true;
}
@@ -202,50 +200,45 @@ struct File_header
struct File_trailer
{
- uint8_t data_crc_[4]; // CRC32 of the uncompressed data
- uint8_t data_size_[8]; // size of the uncompressed data
- uint8_t member_size_[8]; // member size including header and trailer
+ uint8_t data[20]; // 0-3 CRC32 of the uncompressed data
+ // 4-11 size of the uncompressed data
+ // 12-19 member size including header and trailer
- static int size( const int version )
- { return sizeof (File_trailer) - ( ( version >= 1 ) ? 0 : 8 ); }
+ static int size( const int version = 1 )
+ { return ( ( version >= 1 ) ? 20 : 12 ); }
uint32_t data_crc() const throw()
{
uint32_t tmp = 0;
- for( int i = 3; i >= 0; --i ) { tmp <<= 8; tmp += data_crc_[i]; }
+ for( int i = 3; i >= 0; --i ) { tmp <<= 8; tmp += data[i]; }
return tmp;
}
void data_crc( uint32_t crc ) throw()
- {
- for( int i = 0; i < 4; ++i )
- { data_crc_[i] = (uint8_t)crc; crc >>= 8; }
- }
+ { for( int i = 0; i <= 3; ++i ) { data[i] = (uint8_t)crc; crc >>= 8; } }
long long data_size() const throw()
{
long long tmp = 0;
- for( int i = 7; i >= 0; --i ) { tmp <<= 8; tmp += data_size_[i]; }
+ for( int i = 11; i >= 4; --i ) { tmp <<= 8; tmp += data[i]; }
return tmp;
}
- void data_size( long long size ) throw()
+ void data_size( long long sz ) throw()
{
- for( int i = 0; i < 8; ++i )
- { data_size_[i] = (uint8_t)size; size >>= 8; }
+ for( int i = 4; i <= 11; ++i ) { data[i] = (uint8_t)sz; sz >>= 8; }
}
long long member_size() const throw()
{
long long tmp = 0;
- for( int i = 7; i >= 0; --i ) { tmp <<= 8; tmp += member_size_[i]; }
+ for( int i = 19; i >= 12; --i ) { tmp <<= 8; tmp += data[i]; }
return tmp;
}
- void member_size( long long size ) throw()
+ void member_size( long long sz ) throw()
{
- for( int i = 0; i < 8; ++i )
- { member_size_[i] = (uint8_t)size; size >>= 8; }
+ for( int i = 12; i <= 19; ++i ) { data[i] = (uint8_t)sz; sz >>= 8; }
}
};