diff options
Diffstat (limited to 'library/zstring.h')
| -rw-r--r-- | library/zstring.h | 169 |
1 files changed, 125 insertions, 44 deletions
diff --git a/library/zstring.h b/library/zstring.h index 60ba464c..2a10efa9 100644 --- a/library/zstring.h +++ b/library/zstring.h @@ -7,7 +7,11 @@ #ifndef ZSTRING_H_INCLUDED #define ZSTRING_H_INCLUDED -#include <string> +#include <cstring> +#include <cctype> +#include <assert.h> +#include <new> +#include <cstdlib> namespace FreeFileSync @@ -33,6 +37,7 @@ typedef char DefaultChar; typedef wchar_t DefaultChar; #endif +class Zsubstr; class Zstring { @@ -67,7 +72,8 @@ public: //std::string functions size_t length() const; const DefaultChar* c_str() const; - Zstring substr(size_t pos = 0, size_t len = npos) const; + Zstring substr(size_t pos = 0, size_t len = npos) const; //allocate new string + Zsubstr zsubstr(size_t pos = 0) const; //use ref-counting! bool empty() const; int compare(const DefaultChar* other) const; int compare(const Zstring& other) const; @@ -106,18 +112,35 @@ private: struct StringDescriptor { - StringDescriptor(const unsigned int refC, const size_t len, const size_t cap) : refCount(refC), length(len), capacity(cap) {} mutable unsigned int refCount; - size_t length; - size_t capacity; //allocated length without null-termination + size_t length; + size_t capacity; //allocated length without null-termination }; - static void allocate(const unsigned int newRefCount, const size_t newLength, const size_t newCapacity, Zstring::StringDescriptor*& newDescr, DefaultChar*& newData); + static void allocate(const size_t newLength, Zstring::StringDescriptor*& newDescr, DefaultChar*& newData); StringDescriptor* descr; DefaultChar* data; }; +class Zsubstr //ref-counted substring of a Zstring +{ +public: + Zsubstr(); + Zsubstr(const Zstring& ref, const size_t pos); + + const DefaultChar* c_str() const; + size_t length() const; + bool StartsWith(const Zstring& begin) const; + size_t findFromEnd(const DefaultChar ch) const; + +private: + Zstring m_ref; + const DefaultChar* m_data; + size_t m_length; +}; + + //####################################################################################### //begin of implementation @@ -218,28 +241,26 @@ void testZstringForMemoryLeak(); inline -void Zstring::allocate(const unsigned int newRefCount, - const size_t newLength, - const size_t newCapacity, +size_t getCapacityToAllocate(const size_t length) +{ + return (length + (19 - length % 16)); //allocate some additional length to speed up concatenation +} + + +inline +void Zstring::allocate(const size_t newLength, StringDescriptor*& newDescr, DefaultChar*& newData) { //allocate and set data for new string - if (newCapacity) - { - newDescr = (StringDescriptor*) malloc( sizeof(StringDescriptor) + (newCapacity + 1) * sizeof(DefaultChar)); - if (newDescr == NULL) - throw std::bad_alloc(); - newData = (DefaultChar*)(newDescr + 1); - } - else - { - newDescr = (StringDescriptor*) malloc( sizeof(StringDescriptor)); - if (newDescr == NULL) - throw std::bad_alloc(); - newData = NULL; - } + const size_t newCapacity = getCapacityToAllocate(newLength); + assert(newCapacity); + + newDescr = (StringDescriptor*) malloc( sizeof(StringDescriptor) + (newCapacity + 1) * sizeof(DefaultChar)); + if (newDescr == NULL) + throw std::bad_alloc(); + newData = (DefaultChar*)(newDescr + 1); - newDescr->refCount = newRefCount; + newDescr->refCount = 1; newDescr->length = newLength; newDescr->capacity = newCapacity; @@ -259,7 +280,16 @@ void Zstring::allocate(const unsigned int newRefCount, inline Zstring::Zstring() { - allocate(1, 0, 0, descr, data); + //static (dummy) empty Zstring +#ifdef ZSTRING_CHAR + static Zstring emptyString(""); +#elif defined ZSTRING_WIDE_CHAR + static Zstring emptyString(L""); +#endif + + emptyString.incRef(); //implicitly handle case "this == &source" and avoid this check + descr = emptyString.descr; + data = emptyString.data; } @@ -281,7 +311,7 @@ inline Zstring::Zstring(const Zstring& source) { descr = source.descr; - data = source.data; + data = source.data; incRef(); //reference counting! } @@ -294,17 +324,9 @@ Zstring::~Zstring() inline -size_t getCapacityToAllocate(const size_t length) -{ - return (length + (19 - length % 16)); //allocate some additional length to speed up concatenation -} - - -inline void Zstring::initAndCopy(const DefaultChar* source, size_t length) { - const size_t newCapacity = getCapacityToAllocate(length); - allocate(1, length, newCapacity, descr, data); + allocate(length, descr, data); memcpy(data, source, length * sizeof(DefaultChar)); data[length] = 0; } @@ -548,21 +570,14 @@ size_t Zstring::size() const inline const DefaultChar* Zstring::c_str() const { - if (length()) - return data; - else -#ifdef ZSTRING_CHAR - return ""; -#elif defined ZSTRING_WIDE_CHAR - return L""; -#endif + return data; } inline bool Zstring::empty() const { - return length() == 0; + return descr->length == 0; } @@ -594,5 +609,71 @@ Zstring Zstring::operator+(const DefaultChar ch) const return Zstring(*this)+=ch; } +//##################### Zsubstr ############################# +inline +Zsubstr Zstring::zsubstr(size_t pos) const +{ + assert(pos <= length()); + return Zsubstr(*this, pos); //return reference counted string +} + + +inline +Zsubstr::Zsubstr() +{ + m_data = m_ref.c_str(); + m_length = 0; +} + + +inline +Zsubstr::Zsubstr(const Zstring& ref, const size_t pos) : + m_ref(ref), + m_data(ref.c_str() + pos), + m_length(ref.length() - pos) {} + + +inline +const DefaultChar* Zsubstr::c_str() const +{ + return m_data; +} + + +inline +size_t Zsubstr::length() const +{ + return m_length; +} + + +inline +bool Zsubstr::StartsWith(const Zstring& begin) const +{ + const size_t beginLength = begin.length(); + if (length() < beginLength) + return false; + + return defaultCompare(m_data, begin.c_str(), beginLength) == 0; +} + + +inline +size_t Zsubstr::findFromEnd(const DefaultChar ch) const +{ + if (length() == 0) + return Zstring::npos; + + size_t pos = length() - 1; + do //pos points to last char of the string + { + if (m_data[pos] == ch) + return pos; + } + while (--pos != static_cast<size_t>(-1)); + return Zstring::npos; +} + + #endif // ZSTRING_H_INCLUDED |