X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/414b7b40164c4b146c4518d4873cbee9570a222e..38534f596974042130716a26276e9564b0b72295:/include/wx/buffer.h diff --git a/include/wx/buffer.h b/include/wx/buffer.h index 55068fb0cb..951777a13c 100644 --- a/include/wx/buffer.h +++ b/include/wx/buffer.h @@ -12,126 +12,413 @@ #ifndef _WX_BUFFER_H #define _WX_BUFFER_H -#include "wx/wxchar.h" +#include "wx/chartype.h" +#include "wx/wxcrtbase.h" #include // malloc() and free() +class WXDLLIMPEXP_FWD_BASE wxCStrData; + // ---------------------------------------------------------------------------- // Special classes for (wide) character strings: they use malloc/free instead // of new/delete // ---------------------------------------------------------------------------- -#define DEFINE_BUFFER(classname, chartype, strdupfunc) \ -class WXDLLIMPEXP_BASE classname \ -{ \ -public: \ - classname(const chartype *str = NULL) \ - : m_str(str ? strdupfunc(str) : NULL) \ - { \ - } \ - \ - classname(const wxCStrData& cstr); \ - \ - classname(size_t len) \ - : m_str((chartype *)malloc((len + 1)*sizeof(chartype))) \ - { \ - m_str[len] = (chartype)0; \ - } \ - \ - /* no need to check for NULL, free() does it */ \ - ~classname() { free(m_str); } \ - \ - /* \ - WARNING: \ - \ - the copy ctor and assignment operators change the passed in object \ - even although it is declared as "const", so: \ - \ - a) it shouldn't be really const \ - b) you shouldn't use it afterwards (or know that it was reset) \ - \ - This is very ugly but is unfortunately needed to make the normal use\ - of classname buffer objects possible and is very similar to what \ - std::auto_ptr<> does (as if it were an excuse...) \ - */ \ - \ - /* \ - because of the remark above, release() is declared const even if it \ - isn't really const \ - */ \ - chartype *release() const \ - { \ - chartype *p = m_str; \ - ((classname *)this)->m_str = NULL; \ - return p; \ - } \ - \ - void reset() \ - { \ - free(m_str); \ - m_str = NULL; \ - } \ - \ - classname(const classname& src) \ - : m_str(src.release()) \ - { \ - } \ - \ - classname& operator=(const chartype *str) \ - { \ - free(m_str); \ - m_str = str ? strdupfunc(str) : NULL; \ - return *this; \ - } \ - \ - classname& operator=(const classname& src) \ - { \ - free(m_str); \ - m_str = src.release(); \ - \ - return *this; \ - } \ - \ - bool extend(size_t len) \ - { \ - chartype * \ - str = (chartype *)realloc(m_str, (len + 1)*sizeof(chartype)); \ - if ( !str ) \ - return false; \ - \ - m_str = str; \ - \ - return true; \ - } \ - \ - chartype *data() { return m_str; } \ - const chartype *data() const { return m_str; } \ - operator const chartype *() const { return m_str; } \ - chartype operator[](size_t n) const { return m_str[n]; } \ - \ -private: \ - chartype *m_str; \ -} - -DEFINE_BUFFER(wxCharBuffer, char, wxStrdupA); - -#if wxUSE_WCHAR_T - -DEFINE_BUFFER(wxWCharBuffer, wchar_t, wxStrdupW); - -#endif // wxUSE_WCHAR_T - -#undef DEFINE_BUFFER +// helpers used by wxCharTypeBuffer +namespace wxPrivate +{ + +struct UntypedBufferData +{ + enum Kind + { + Owned, + NonOwned + }; + + UntypedBufferData(void *str, size_t len, Kind kind = Owned) + : m_str(str), m_length(len), m_ref(1), m_owned(kind == Owned) {} + + ~UntypedBufferData() + { + if ( m_owned ) + free(m_str); + } + + void *m_str; + size_t m_length; + + // "short" to have sizeof(Data)=12 on 32bit archs + unsigned short m_ref; + + bool m_owned; +}; + +// NB: this is defined in string.cpp and not the (non-existent) buffer.cpp +WXDLLIMPEXP_BASE UntypedBufferData * GetUntypedNullData(); + +} // namespace wxPrivate + + +// Reference-counted character buffer for storing string data. The buffer +// is only valid for as long as the "parent" object that provided the data +// is valid; see wxCharTypeBuffer for persistent variant. +template +class wxScopedCharTypeBuffer +{ +public: + typedef T CharType; + + wxScopedCharTypeBuffer() + { + m_data = GetNullData(); + } + + // Creates "non-owned" buffer, i.e. 'str' is not owned by the buffer + // and doesn't get freed by dtor. Used e.g. to point to wxString's internal + // storage. + static + const wxScopedCharTypeBuffer CreateNonOwned(const CharType *str, + size_t len = wxNO_LEN) + { + if ( len == wxNO_LEN ) + len = wxStrlen(str); + + wxScopedCharTypeBuffer buf; + if ( str ) + buf.m_data = new Data(const_cast(str), len, Data::NonOwned); + return buf; + } + + // Creates "owned" buffer, i.e. takes over ownership of 'str' and frees it + // in dtor (if ref.count reaches 0). + static + const wxScopedCharTypeBuffer CreateOwned(CharType *str, + size_t len = wxNO_LEN ) + { + if ( len == wxNO_LEN ) + len = wxStrlen(str); + + wxScopedCharTypeBuffer buf; + if ( str ) + buf.m_data = new Data(str, len); + return buf; + } + + wxScopedCharTypeBuffer(const wxScopedCharTypeBuffer& src) + { + m_data = src.m_data; + IncRef(); + } + + wxScopedCharTypeBuffer& operator=(const wxScopedCharTypeBuffer& src) + { + if ( &src == this ) + return *this; + + DecRef(); + m_data = src.m_data; + IncRef(); + + return *this; + } + + ~wxScopedCharTypeBuffer() + { + DecRef(); + } + + // NB: this method is only const for backward compatibility. It used to + // be needed for auto_ptr-like semantics of the copy ctor, but now + // that ref-counting is used, it's not really needed. + CharType *release() const + { + if ( m_data == GetNullData() ) + return NULL; + + wxASSERT_MSG( m_data->m_owned, wxT("can't release non-owned buffer") ); + wxASSERT_MSG( m_data->m_ref == 1, wxT("can't release shared buffer") ); + + CharType * const p = m_data->Get(); + + wxScopedCharTypeBuffer *self = const_cast(this); + self->m_data->Set(NULL, 0); + self->DecRef(); + + return p; + } + + void reset() + { + DecRef(); + } + + CharType *data() { return m_data->Get(); } + const CharType *data() const { return m_data->Get(); } + operator const CharType *() const { return data(); } + CharType operator[](size_t n) const { return data()[n]; } + + size_t length() const { return m_data->m_length; } + +protected: + // reference-counted data + struct Data : public wxPrivate::UntypedBufferData + { + Data(CharType *str, size_t len, Kind kind = Owned) + : wxPrivate::UntypedBufferData(str, len, kind) + { + } + + CharType *Get() const { return static_cast(m_str); } + void Set(CharType *str, size_t len) + { + m_str = str; + m_length = len; + } + }; + + // placeholder for NULL string, to simplify this code + static Data *GetNullData() + { + return static_cast(wxPrivate::GetUntypedNullData()); + } + + void IncRef() + { + if ( m_data == GetNullData() ) // exception, not ref-counted + return; + m_data->m_ref++; + } + + void DecRef() + { + if ( m_data == GetNullData() ) // exception, not ref-counted + return; + if ( --m_data->m_ref == 0 ) + delete m_data; + m_data = GetNullData(); + } + + // sets this object to a be copy of 'other'; if 'src' is non-owned, + // a deep copy is made and 'this' will contain new instance of the data + void MakeOwnedCopyOf(const wxScopedCharTypeBuffer& src) + { + this->DecRef(); + + if ( src.m_data == this->GetNullData() ) + { + this->m_data = this->GetNullData(); + } + else if ( src.m_data->m_owned ) + { + this->m_data = src.m_data; + this->IncRef(); + } + else + { + // if the scoped buffer had non-owned data, we have to make + // a copy here, because src.m_data->m_str is valid only for as long + // as 'src' exists + this->m_data = new Data + ( + StrCopy(src.data(), src.length()), + src.length() + ); + } + } + + static CharType *StrCopy(const CharType *src, size_t len) + { + CharType *dst = (CharType*)malloc(sizeof(CharType) * (len + 1)); + if ( dst ) + memcpy(dst, src, sizeof(CharType) * (len + 1)); + return dst; + } + +protected: + Data *m_data; +}; + +typedef wxScopedCharTypeBuffer wxScopedCharBuffer; +typedef wxScopedCharTypeBuffer wxScopedWCharBuffer; + + +// this buffer class always stores data in "owned" (persistent) manner +template +class wxCharTypeBuffer : public wxScopedCharTypeBuffer +{ +protected: + typedef typename wxScopedCharTypeBuffer::Data Data; + +public: + typedef T CharType; + + wxCharTypeBuffer(const CharType *str = NULL, size_t len = wxNO_LEN) + { + if ( str ) + { + if ( len == wxNO_LEN ) + len = wxStrlen(str); + this->m_data = new Data(this->StrCopy(str, len), len); + } + else + { + this->m_data = this->GetNullData(); + } + } + + wxCharTypeBuffer(size_t len) + { + this->m_data = + new Data((CharType *)malloc((len + 1)*sizeof(CharType)), len); + this->m_data->Get()[len] = (CharType)0; + } + + wxCharTypeBuffer(const wxCharTypeBuffer& src) + : wxScopedCharTypeBuffer(src) {} + + wxCharTypeBuffer& operator=(const CharType *str) + { + this->DecRef(); + + if ( str ) + this->m_data = new Data(wxStrdup(str), wxStrlen(str)); + return *this; + } + + wxCharTypeBuffer& operator=(const wxCharTypeBuffer& src) + { + wxScopedCharTypeBuffer::operator=(src); + return *this; + } + + wxCharTypeBuffer(const wxScopedCharTypeBuffer& src) + { + this->MakeOwnedCopyOf(src); + } + + wxCharTypeBuffer& operator=(const wxScopedCharTypeBuffer& src) + { + MakeOwnedCopyOf(src); + return *this; + } + + bool extend(size_t len) + { + wxASSERT_MSG( this->m_data->m_owned, "cannot extend non-owned buffer" ); + wxASSERT_MSG( this->m_data->m_ref == 1, "can't extend shared buffer" ); + + CharType *str = + (CharType *)realloc(this->data(), (len + 1) * sizeof(CharType)); + if ( !str ) + return false; + + // For consistency with the ctor taking just the length, NUL-terminate + // the buffer. + str[len] = (CharType)0; + + if ( this->m_data == this->GetNullData() ) + { + this->m_data = new Data(str, len); + } + else + { + this->m_data->Set(str, len); + this->m_data->m_owned = true; + } + + return true; + } + + void shrink(size_t len) + { + wxASSERT_MSG( this->m_data->m_owned, "cannot shrink non-owned buffer" ); + wxASSERT_MSG( this->m_data->m_ref == 1, "can't shrink shared buffer" ); + + wxASSERT( len <= this->length() ); + + this->m_data->m_length = len; + this->data()[len] = 0; + } +}; + +WXDLLIMPEXP_TEMPLATE_INSTANCE_BASE( wxScopedCharTypeBuffer ) +WXDLLIMPEXP_TEMPLATE_INSTANCE_BASE( wxCharTypeBuffer ) + +class wxCharBuffer : public wxCharTypeBuffer +{ +public: + typedef wxCharTypeBuffer wxCharTypeBufferBase; + typedef wxScopedCharTypeBuffer wxScopedCharTypeBufferBase; + + wxCharBuffer(const wxCharTypeBufferBase& buf) + : wxCharTypeBufferBase(buf) {} + wxCharBuffer(const wxScopedCharTypeBufferBase& buf) + : wxCharTypeBufferBase(buf) {} + + wxCharBuffer(const CharType *str = NULL) : wxCharTypeBufferBase(str) {} + wxCharBuffer(size_t len) : wxCharTypeBufferBase(len) {} + + wxCharBuffer(const wxCStrData& cstr); +}; + +WXDLLIMPEXP_TEMPLATE_INSTANCE_BASE( wxScopedCharTypeBuffer ) +WXDLLIMPEXP_TEMPLATE_INSTANCE_BASE( wxCharTypeBuffer ) + +class wxWCharBuffer : public wxCharTypeBuffer +{ +public: + typedef wxCharTypeBuffer wxCharTypeBufferBase; + typedef wxScopedCharTypeBuffer wxScopedCharTypeBufferBase; + + wxWCharBuffer(const wxCharTypeBufferBase& buf) + : wxCharTypeBufferBase(buf) {} + wxWCharBuffer(const wxScopedCharTypeBufferBase& buf) + : wxCharTypeBufferBase(buf) {} + + wxWCharBuffer(const CharType *str = NULL) : wxCharTypeBufferBase(str) {} + wxWCharBuffer(size_t len) : wxCharTypeBufferBase(len) {} + + wxWCharBuffer(const wxCStrData& cstr); +}; + +// wxCharTypeBuffer implicitly convertible to T* +template +class wxWritableCharTypeBuffer : public wxCharTypeBuffer +{ +public: + typedef typename wxScopedCharTypeBuffer::CharType CharType; + + wxWritableCharTypeBuffer(const wxScopedCharTypeBuffer& src) + : wxCharTypeBuffer(src) {} + // FIXME-UTF8: this won't be needed after converting mb_str()/wc_str() to + // always return a buffer + // + we should derive this class from wxScopedCharTypeBuffer + // then + wxWritableCharTypeBuffer(const CharType *str = NULL) + : wxCharTypeBuffer(str) {} + + operator CharType*() { return this->data(); } +}; + +typedef wxWritableCharTypeBuffer wxWritableCharBuffer; +typedef wxWritableCharTypeBuffer wxWritableWCharBuffer; + #if wxUSE_UNICODE - typedef wxWCharBuffer wxWxCharBuffer; + #define wxWxCharBuffer wxWCharBuffer #define wxMB2WXbuf wxWCharBuffer #define wxWX2MBbuf wxCharBuffer - #define wxWC2WXbuf wxChar* - #define wxWX2WCbuf wxChar* + #if wxUSE_UNICODE_WCHAR + #define wxWC2WXbuf wxChar* + #define wxWX2WCbuf wxChar* + #elif wxUSE_UNICODE_UTF8 + #define wxWC2WXbuf wxWCharBuffer + #define wxWX2WCbuf wxWCharBuffer + #endif #else // ANSI - typedef wxCharBuffer wxWxCharBuffer; + #define wxWxCharBuffer wxCharBuffer #define wxMB2WXbuf wxChar* #define wxWX2MBbuf wxChar* @@ -152,7 +439,7 @@ public: friend class wxMemoryBuffer; - // everyting is private as it can only be used by wxMemoryBuffer + // everything is private as it can only be used by wxMemoryBuffer private: wxMemoryBufferData(size_t size = wxMemoryBufferData::DefBufSize) : m_data(size ? malloc(size) : NULL), m_size(size), m_len(0), m_ref(0) @@ -184,6 +471,21 @@ private: delete this; } + void *release() + { + if ( m_data == NULL ) + return NULL; + + wxASSERT_MSG( m_ref == 1, "can't release shared buffer" ); + + void *p = m_data; + m_data = NULL; + m_len = + m_size = 0; + + return p; + } + // the buffer containing the data void *m_data; @@ -197,7 +499,7 @@ private: // the reference count size_t m_ref; - DECLARE_NO_COPY_CLASS(wxMemoryBufferData) + wxDECLARE_NO_COPY_CLASS(wxMemoryBufferData); }; @@ -223,9 +525,12 @@ public: wxMemoryBuffer& operator=(const wxMemoryBuffer& src) { - m_bufdata->DecRef(); - m_bufdata = src.m_bufdata; - m_bufdata->IncRef(); + if (&src != this) + { + m_bufdata->DecRef(); + m_bufdata = src.m_bufdata; + m_bufdata->IncRef(); + } return *this; } @@ -235,6 +540,8 @@ public: size_t GetBufSize() const { return m_bufdata->m_size; } size_t GetDataLen() const { return m_bufdata->m_len; } + bool IsEmpty() const { return GetDataLen() == 0; } + void SetBufSize(size_t size) { m_bufdata->ResizeIfNeeded(size); } void SetDataLen(size_t len) { @@ -242,6 +549,8 @@ public: m_bufdata->m_len = len; } + void Clear() { SetDataLen(0); } + // Ensure the buffer is big enough and return a pointer to it void *GetWriteBuf(size_t sizeNeeded) { @@ -268,7 +577,7 @@ public: // Other ways to append to the buffer void AppendByte(char data) { - wxCHECK_RET( m_bufdata->m_data, _T("invalid wxMemoryBuffer") ); + wxCHECK_RET( m_bufdata->m_data, wxT("invalid wxMemoryBuffer") ); m_bufdata->ResizeIfNeeded(m_bufdata->m_len + 1); *(((char*)m_bufdata->m_data) + m_bufdata->m_len) = data; @@ -283,6 +592,13 @@ public: operator const char *() const { return (const char*)GetData(); } + // gives up ownership of data, returns the pointer; after this call, + // data isn't freed by the buffer and its content is resent to empty + void *release() + { + return m_bufdata->release(); + } + private: wxMemoryBufferData* m_bufdata; };