#include <string.h>
+#if defined(_MSC_VER) && _MSC_VER >= 1400 && (defined(_M_IX86) || defined(_M_X64))
+# define TAGLIB_MSC_BYTESWAP
+#elif defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
+# define TAGLIB_GCC_BYTESWAP
+#endif
+
+#ifdef TAGLIB_GCC_BYTESWAP
+# include <byteswap.h>
+#endif
+
#include "tbytevector.h"
// This is a bit ugly to keep writing over and over again.
//
// http://www.informit.com/isapi/product_id~{9C84DAB4-FE6E-49C5-BB0A-FB50331233EA}/content/index.asp
-#define DATA(x) (&(x->data[0]))
+#define DATA(x) (&(x->data->data[0]))
namespace TagLib {
static const char hexTable[17] = "0123456789abcdef";
};
/*!
- * A templatized KMP find that works both with a ByteVector and a ByteVectorMirror.
+ * A templatized straightforward find that works with the types
+ * std::vector<char>::iterator and std::vector<char>::reverse_iterator.
*/
-
- template <class Vector>
- int vectorFind(const Vector &v, const Vector &pattern, uint offset, int byteAlign)
+ template <class TIterator>
+ int findChar(
+ const TIterator dataBegin, const TIterator dataEnd,
+ char c, uint offset, int byteAlign)
{
- if(pattern.size() > v.size() || offset > v.size() - 1)
+ const size_t dataSize = dataEnd - dataBegin;
+ if(dataSize == 0 || offset > dataSize - 1)
return -1;
- // Let's go ahead and special case a pattern of size one since that's common
- // and easy to make fast.
+ // n % 0 is invalid
- if(pattern.size() == 1) {
- char p = pattern[0];
- for(uint i = offset; i < v.size(); i++) {
- if(v[i] == p && (i - offset) % byteAlign == 0)
- return i;
- }
+ if(byteAlign == 0)
return -1;
+
+ for(TIterator it = dataBegin + offset; it < dataEnd; it += byteAlign) {
+ if(*it == c)
+ return (it - dataBegin);
}
- uchar lastOccurrence[256];
+ return -1;
+ }
+
+ /*!
+ * A templatized KMP find that works with the types
+ * std::vector<char>::iterator and std::vector<char>::reverse_iterator.
+ */
+ template <class TIterator>
+ int findVector(
+ const TIterator dataBegin, const TIterator dataEnd,
+ const TIterator patternBegin, const TIterator patternEnd,
+ uint offset, int byteAlign)
+ {
+ const size_t dataSize = dataEnd - dataBegin;
+ const size_t patternSize = patternEnd - patternBegin;
+ if(patternSize > dataSize || offset > dataSize - 1)
+ return -1;
+
+ // n % 0 is invalid
- for(uint i = 0; i < 256; ++i)
- lastOccurrence[i] = uchar(pattern.size());
+ if(byteAlign == 0)
+ return -1;
- for(uint i = 0; i < pattern.size() - 1; ++i)
- lastOccurrence[uchar(pattern[i])] = uchar(pattern.size() - i - 1);
+ // Special case that pattern contains just single char.
- for(uint i = pattern.size() - 1 + offset; i < v.size(); i += lastOccurrence[uchar(v.at(i))]) {
- int iBuffer = i;
- int iPattern = pattern.size() - 1;
+ if(patternSize == 1)
+ return findChar(dataBegin, dataEnd, *patternBegin, offset, byteAlign);
- while(iPattern >= 0 && v.at(iBuffer) == pattern[iPattern]) {
- --iBuffer;
- --iPattern;
- }
+ size_t lastOccurrence[256];
- if(-1 == iPattern && (iBuffer + 1 - offset) % byteAlign == 0)
- return iBuffer + 1;
+ for(size_t i = 0; i < 256; ++i)
+ lastOccurrence[i] = patternSize;
+
+ for(size_t i = 0; i < patternSize - 1; ++i)
+ lastOccurrence[static_cast<uchar>(*(patternBegin + i))] = patternSize - i - 1;
+
+ for(TIterator it = dataBegin + patternSize - 1 + offset;
+ it < dataEnd;
+ it += lastOccurrence[static_cast<uchar>(*it)])
+ {
+ TIterator itBuffer = it;
+ TIterator itPattern = patternBegin + patternSize - 1;
+
+ while(*itBuffer == *itPattern)
+ {
+ if(itPattern == patternBegin)
+ {
+ if((itBuffer - dataBegin - offset) % byteAlign == 0)
+ return (itBuffer - dataBegin);
+ else
+ break;
+ }
+
+ --itBuffer;
+ --itPattern;
+ }
}
return -1;
}
- /*!
- * Wraps the accessors to a ByteVector to make the search algorithm access the
- * elements in reverse.
- *
- * \see vectorFind()
- * \see ByteVector::rfind()
- */
+#if defined(TAGLIB_MSC_BYTESWAP) || defined(TAGLIB_GCC_BYTESWAP)
- class ByteVectorMirror
+ template <class T>
+ T byteSwap(T x)
{
- public:
- ByteVectorMirror(const ByteVector &source) : v(source) {}
+ // There should be all counterparts of to*() and from*() overloads for integral types.
+ debug("byteSwap<T>() -- Non specialized version should not be called");
+ return 0;
+ }
- char operator[](int index) const
- {
- return v[v.size() - index - 1];
- }
+#endif
- char at(int index) const
- {
- return v.at(v.size() - index - 1);
- }
+#ifdef TAGLIB_MSC_BYTESWAP
- ByteVectorMirror mid(uint index, uint length = 0xffffffff) const
- {
- return length == 0xffffffff ? v.mid(0, index) : v.mid(index - length, length);
- }
+ template <>
+ unsigned short byteSwap<unsigned short>(unsigned short x)
+ {
+ return _byteswap_ushort(x);
+ }
- uint size() const
- {
- return v.size();
- }
+ template <>
+ unsigned int byteSwap<unsigned int>(unsigned int x)
+ {
+ return _byteswap_ulong(x);
+ }
- int find(const ByteVectorMirror &pattern, uint offset = 0, int byteAlign = 1) const
- {
- ByteVectorMirror v(*this);
+ template <>
+ unsigned long long byteSwap<unsigned long long>(unsigned long long x)
+ {
+ return _byteswap_uint64(x);
+ }
- if(offset > 0) {
- offset = size() - offset - pattern.size();
- if(offset >= size())
- offset = 0;
- }
+#endif
- const int pos = vectorFind<ByteVectorMirror>(v, pattern, offset, byteAlign);
+#ifdef TAGLIB_GCC_BYTESWAP
- // If the offset is zero then we need to adjust the location in the search
- // to be appropriately reversed. If not we need to account for the fact
- // that the recursive call (called from the above line) has already ajusted
- // for this but that the normal templatized find above will add the offset
- // to the returned value.
- //
- // This is a little confusing at first if you don't first stop to think
- // through the logic involved in the forward search.
+ template <>
+ unsigned short byteSwap<unsigned short>(unsigned short x)
+ {
+ return __bswap_16(x);
+ }
- if(pos == -1)
- return -1;
+ template <>
+ unsigned int byteSwap<unsigned int>(unsigned int x)
+ {
+ return __bswap_32(x);
+ }
- return size() - pos - pattern.size();
- }
+ template <>
+ unsigned long long byteSwap<unsigned long long>(unsigned long long x)
+ {
+ return __bswap_64(x);
+ }
- private:
- const ByteVector &v;
- };
+#endif
template <class T>
- T toNumber(const std::vector<char> &data, bool mostSignificantByteFirst)
+ T toNumber(const ByteVector &v, bool mostSignificantByteFirst)
{
- T sum = 0;
+ if(v.isEmpty()) {
+ debug("toNumber<T>() -- data is empty, returning 0");
+ return 0;
+ }
- if(data.size() <= 0) {
- debug("ByteVectorMirror::toNumber<T>() -- data is empty, returning 0");
- return sum;
+ const size_t size = sizeof(T);
+
+#if defined(TAGLIB_MSC_BYTESWAP) || defined(TAGLIB_GCC_BYTESWAP)
+
+ if(v.size() >= size)
+ {
+ if(mostSignificantByteFirst)
+ return byteSwap(*reinterpret_cast<const T*>(v.data()));
+ else
+ return *reinterpret_cast<const T*>(v.data());
}
- uint size = sizeof(T);
- uint last = data.size() > size ? size - 1 : data.size() - 1;
+#endif
+ const uint last = v.size() > size ? size - 1 : v.size() - 1;
+ T sum = 0;
for(uint i = 0; i <= last; i++)
- sum |= (T) uchar(data[i]) << ((mostSignificantByteFirst ? last - i : i) * 8);
+ sum |= (T) uchar(v[i]) << ((mostSignificantByteFirst ? last - i : i) * 8);
return sum;
}
template <class T>
ByteVector fromNumber(T value, bool mostSignificantByteFirst)
{
- int size = sizeof(T);
+ const size_t size = sizeof(T);
- ByteVector v(size, 0);
+#if defined(TAGLIB_MSC_BYTESWAP) || defined(TAGLIB_GCC_BYTESWAP)
- for(int i = 0; i < size; i++)
+ if(mostSignificantByteFirst)
+ value = byteSwap(value);
+
+ return ByteVector(reinterpret_cast<const char *>(&value), size);
+
+#else
+
+ ByteVector v(size, 0);
+ for(uint i = 0; i < size; i++)
v[i] = uchar(value >> ((mostSignificantByteFirst ? size - 1 - i : i) * 8) & 0xff);
return v;
+
+#endif
}
}
using namespace TagLib;
-class ByteVector::ByteVectorPrivate : public RefCounter
+class DataPrivate : public RefCounter
{
public:
- ByteVectorPrivate() : RefCounter(), size(0) {}
- ByteVectorPrivate(const std::vector<char> &v) : RefCounter(), data(v), size(v.size()) {}
- ByteVectorPrivate(TagLib::uint len, char value) : RefCounter(), data(len, value), size(len) {}
+ DataPrivate()
+ {
+ }
+
+ DataPrivate(const std::vector<char> &v, uint offset, uint length)
+ : data(v.begin() + offset, v.begin() + offset + length)
+ {
+ }
+
+ DataPrivate(uint len, char c)
+ : data(len, c)
+ {
+ }
std::vector<char> data;
+};
- // std::vector<T>::size() is very slow, so we'll cache the value
+class ByteVector::ByteVectorPrivate : public RefCounter
+{
+public:
+ ByteVectorPrivate()
+ : RefCounter()
+ , data(new DataPrivate())
+ , offset(0)
+ , length(0)
+ {
+ }
- uint size;
+ ByteVectorPrivate(ByteVectorPrivate *d, uint o, uint l)
+ : RefCounter()
+ , data(d->data)
+ , offset(d->offset + o)
+ , length(l)
+ {
+ data->ref();
+ }
+
+ ByteVectorPrivate(const std::vector<char> &v, uint o, uint l)
+ : RefCounter()
+ , data(new DataPrivate(v, o, l))
+ , offset(0)
+ , length(l)
+ {
+ }
+
+ ByteVectorPrivate(uint l, char c)
+ : RefCounter()
+ , data(new DataPrivate(l, c))
+ , offset(0)
+ , length(l)
+ {
+ }
+
+ ByteVectorPrivate(const char *s, uint l)
+ : RefCounter()
+ , data(new DataPrivate())
+ , offset(0)
+ , length(l)
+ {
+ data->data.resize(length);
+ memcpy(DATA(this), s, l);
+ }
+
+ void detach()
+ {
+ if(data->count() > 1) {
+ data->deref();
+ data = new DataPrivate(data->data, offset, length);
+ offset = 0;
+ }
+ }
+
+ ~ByteVectorPrivate()
+ {
+ if(data->deref())
+ delete data;
+ }
+
+ ByteVectorPrivate &operator=(const ByteVectorPrivate &x)
+ {
+ if(&x != this)
+ {
+ if(data->deref())
+ delete data;
+
+ data = x.data;
+ data->ref();
+ }
+
+ return *this;
+ }
+
+ DataPrivate *data;
+ uint offset;
+ uint length;
};
////////////////////////////////////////////////////////////////////////////////
ByteVector ByteVector::fromCString(const char *s, uint length)
{
- ByteVector v;
-
if(length == 0xffffffff)
- v.setData(s);
+ return ByteVector(s, ::strlen(s));
else
- v.setData(s, length);
-
- return v;
+ return ByteVector(s, length);
}
ByteVector ByteVector::fromUInt(uint value, bool mostSignificantByteFirst)
ByteVector ByteVector::fromShort(short value, bool mostSignificantByteFirst)
{
- return fromNumber<short>(value, mostSignificantByteFirst);
+ return fromNumber<ushort>(value, mostSignificantByteFirst);
}
ByteVector ByteVector::fromLongLong(long long value, bool mostSignificantByteFirst)
{
- return fromNumber<long long>(value, mostSignificantByteFirst);
+ return fromNumber<unsigned long long>(value, mostSignificantByteFirst);
}
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
ByteVector::ByteVector()
+ : d(new ByteVectorPrivate())
{
- d = new ByteVectorPrivate;
}
ByteVector::ByteVector(uint size, char value)
+ : d(new ByteVectorPrivate(size, value))
{
- d = new ByteVectorPrivate(size, value);
}
-ByteVector::ByteVector(const ByteVector &v) : d(v.d)
+ByteVector::ByteVector(const ByteVector &v)
+ : d(v.d)
+{
+ d->ref();
+}
+
+ByteVector::ByteVector(const ByteVector &v, uint offset, uint length)
+ : d(new ByteVectorPrivate(v.d, offset, length))
{
d->ref();
}
ByteVector::ByteVector(char c)
+ : d(new ByteVectorPrivate(1, c))
{
- d = new ByteVectorPrivate;
- d->data.push_back(c);
- d->size = 1;
}
ByteVector::ByteVector(const char *data, uint length)
+ : d(new ByteVectorPrivate(data, length))
{
- d = new ByteVectorPrivate;
- setData(data, length);
}
ByteVector::ByteVector(const char *data)
+ : d(new ByteVectorPrivate(data, ::strlen(data)))
{
- d = new ByteVectorPrivate;
- setData(data);
}
ByteVector::~ByteVector()
delete d;
}
-ByteVector &ByteVector::setData(const char *data, uint length)
+ByteVector &ByteVector::setData(const char *s, uint length)
{
- detach();
-
- resize(length);
-
- if(length > 0)
- ::memcpy(DATA(d), data, length);
-
+ *this = ByteVector(s, length);
return *this;
}
ByteVector &ByteVector::setData(const char *data)
{
- return setData(data, ::strlen(data));
+ *this = ByteVector(data);
+ return *this;
}
char *ByteVector::data()
{
detach();
- return size() > 0 ? DATA(d) : 0;
+ return size() > 0 ? (DATA(d) + d->offset) : 0;
}
const char *ByteVector::data() const
{
- return size() > 0 ? DATA(d) : 0;
+ return size() > 0 ? (DATA(d) + d->offset) : 0;
}
ByteVector ByteVector::mid(uint index, uint length) const
{
- ByteVector v;
-
if(index > size())
- return v;
-
- ConstIterator endIt;
-
- if(length < size() - index)
- endIt = d->data.begin() + index + length;
- else
- endIt = d->data.end();
+ index = size();
- v.d->data.insert(v.d->data.begin(), ConstIterator(d->data.begin() + index), endIt);
- v.d->size = v.d->data.size();
+ if(length > size() - index)
+ length = size() - index;
- return v;
+ return ByteVector(*this, index, length);
}
char ByteVector::at(uint index) const
{
- return index < size() ? d->data[index] : 0;
+ return index < size() ? DATA(d)[d->offset + index] : 0;
}
int ByteVector::find(const ByteVector &pattern, uint offset, int byteAlign) const
{
- return vectorFind<ByteVector>(*this, pattern, offset, byteAlign);
+ return findVector<ConstIterator>(
+ begin(), end(), pattern.begin(), pattern.end(), offset, byteAlign);
+}
+
+int ByteVector::find(char c, uint offset, int byteAlign) const
+{
+ return findChar<ConstIterator>(begin(), end(), c, offset, byteAlign);
}
int ByteVector::rfind(const ByteVector &pattern, uint offset, int byteAlign) const
{
- // Ok, this is a little goofy, but pretty cool after it sinks in. Instead of
- // reversing the find method's Boyer-Moore search algorithm I created a "mirror"
- // for a ByteVector to reverse the behavior of the accessors.
+ if(offset > 0) {
+ offset = size() - offset - pattern.size();
+ if(offset >= size())
+ offset = 0;
+ }
- ByteVectorMirror v(*this);
- ByteVectorMirror p(pattern);
+ const int pos = findVector<ConstReverseIterator>(
+ rbegin(), rend(), pattern.rbegin(), pattern.rend(), offset, byteAlign);
- return v.find(p, offset, byteAlign);
+ if(pos == -1)
+ return -1;
+ else
+ return size() - pos - pattern.size();
}
bool ByteVector::containsAt(const ByteVector &pattern, uint offset, uint patternOffset, uint patternLength) const
// do some sanity checking -- all of these things are needed for the search to be valid
- if(patternLength > size() || offset >= size() || patternOffset >= pattern.size() || patternLength == 0)
+ if(offset + patternLength > size() || patternOffset >= pattern.size() || patternLength == 0)
return false;
-
- // loop through looking for a mismatch
-
- for(uint i = 0; i < patternLength - patternOffset; i++) {
- if(at(i + offset) != pattern[i + patternOffset])
- return false;
- }
-
- return true;
+
+ return (::memcmp(data() + offset, pattern.data() + patternOffset, patternLength - patternOffset) == 0);
}
bool ByteVector::startsWith(const ByteVector &pattern) const
ByteVector &ByteVector::append(const ByteVector &v)
{
- if(v.d->size == 0)
- return *this; // Simply return if appending nothing.
-
- detach();
+ if(v.d->length != 0)
+ {
+ detach();
- uint originalSize = d->size;
- resize(d->size + v.d->size);
- ::memcpy(DATA(d) + originalSize, DATA(v.d), v.size());
+ uint originalSize = size();
+ resize(originalSize + v.size());
+ ::memcpy(data() + originalSize, v.data(), v.size());
+ }
return *this;
}
ByteVector &ByteVector::clear()
{
- detach();
- d->data.clear();
- d->size = 0;
-
+ *this = ByteVector();
return *this;
}
TagLib::uint ByteVector::size() const
{
- return d->size;
+ return d->length;
}
ByteVector &ByteVector::resize(uint size, char padding)
{
- if(d->size < size) {
- d->data.reserve(size);
- d->data.insert(d->data.end(), size - d->size, padding);
- }
- else
- d->data.erase(d->data.begin() + size, d->data.end());
-
- d->size = size;
+ detach();
+ d->data->data.resize(d->offset + size, padding);
+ d->length = size;
return *this;
}
ByteVector::Iterator ByteVector::begin()
{
- return d->data.begin();
+ return d->data->data.begin() + d->offset;
}
ByteVector::ConstIterator ByteVector::begin() const
{
- return d->data.begin();
+ return d->data->data.begin() + d->offset;
}
ByteVector::Iterator ByteVector::end()
{
- return d->data.end();
+ return d->data->data.begin() + d->offset + d->length;
}
ByteVector::ConstIterator ByteVector::end() const
{
- return d->data.end();
+ return d->data->data.begin() + d->offset + d->length;
+}
+
+ByteVector::ReverseIterator ByteVector::rbegin()
+{
+ std::vector<char> &v = d->data->data;
+ return v.rbegin() + (v.size() - (d->offset + d->length));
+}
+
+ByteVector::ConstReverseIterator ByteVector::rbegin() const
+{
+ std::vector<char> &v = d->data->data;
+ return v.rbegin() + (v.size() - (d->offset + d->length));
+}
+
+ByteVector::ReverseIterator ByteVector::rend()
+{
+ std::vector<char> &v = d->data->data;
+ return v.rbegin() + (v.size() - d->offset);
+}
+
+ByteVector::ConstReverseIterator ByteVector::rend() const
+{
+ std::vector<char> &v = d->data->data;
+ return v.rbegin() + (v.size() - d->offset);
}
bool ByteVector::isNull() const
{
- return d == null.d;
+ return (d == null.d);
}
bool ByteVector::isEmpty() const
{
- return d->data.size() == 0;
+ return (d->length == 0);
}
TagLib::uint ByteVector::checksum() const
TagLib::uint ByteVector::toUInt(bool mostSignificantByteFirst) const
{
- return toNumber<uint>(d->data, mostSignificantByteFirst);
+ return toNumber<uint>(*this, mostSignificantByteFirst);
}
short ByteVector::toShort(bool mostSignificantByteFirst) const
{
- return toNumber<unsigned short>(d->data, mostSignificantByteFirst);
+ return toNumber<unsigned short>(*this, mostSignificantByteFirst);
}
unsigned short ByteVector::toUShort(bool mostSignificantByteFirst) const
{
- return toNumber<unsigned short>(d->data, mostSignificantByteFirst);
+ return toNumber<unsigned short>(*this, mostSignificantByteFirst);
}
long long ByteVector::toLongLong(bool mostSignificantByteFirst) const
{
- return toNumber<unsigned long long>(d->data, mostSignificantByteFirst);
+ return toNumber<unsigned long long>(*this, mostSignificantByteFirst);
}
const char &ByteVector::operator[](int index) const
{
- return d->data[index];
+ return d->data->data[d->offset + index];
}
char &ByteVector::operator[](int index)
{
detach();
-
- return d->data[index];
+ return d->data->data[d->offset + index];
}
bool ByteVector::operator==(const ByteVector &v) const
{
- if(d->size != v.d->size)
+ if(size() != v.size())
return false;
- return ::memcmp(data(), v.data(), size()) == 0;
+ return (::memcmp(data(), v.data(), size()) == 0);
}
bool ByteVector::operator!=(const ByteVector &v) const
bool ByteVector::operator==(const char *s) const
{
- if(d->size != ::strlen(s))
+ if(size() != ::strlen(s))
return false;
- return ::memcmp(data(), s, d->size) == 0;
+ return (::memcmp(data(), s, size()) == 0);
}
bool ByteVector::operator!=(const char *s) const
bool ByteVector::operator<(const ByteVector &v) const
{
- int result = ::memcmp(data(), v.data(), d->size < v.d->size ? d->size : v.d->size);
-
+ const int result = ::memcmp(data(), v.data(), std::min(size(), v.size()));
if(result != 0)
return result < 0;
else
ByteVector ByteVector::toHex() const
{
ByteVector encoded(size() * 2);
+ char *p = encoded.data();
- uint j = 0;
for(uint i = 0; i < size(); i++) {
- unsigned char c = d->data[i];
- encoded[j++] = hexTable[(c >> 4) & 0x0F];
- encoded[j++] = hexTable[(c ) & 0x0F];
+ unsigned char c = data()[i];
+ *p++ = hexTable[(c >> 4) & 0x0F];
+ *p++ = hexTable[(c ) & 0x0F];
}
return encoded;
void ByteVector::detach()
{
+ if(d->data->count() > 1) {
+ d->data->deref();
+ d->data = new DataPrivate(d->data->data, d->offset, d->length);
+ d->offset = 0;
+ }
+
if(d->count() > 1) {
d->deref();
- d = new ByteVectorPrivate(d->data);
+ d = new ByteVectorPrivate(d->data->data, d->offset, d->length);
}
}
projects / taglib / commitdiff