core: get rid of built-in String type

modules/core/include/opencv2/core/cvstd.inl.hpp

@@ -73,69 +73,6 @@ public:
     typedef Vec<channel_type, channels> vec_type;
 };
 
-inline
-String::String(const std::string& str)
-    : cstr_(0), len_(0)
-{
-    size_t len = str.size();
-    if (len) memcpy(allocate(len), str.c_str(), len);
-}
-
-inline
-String::String(const std::string& str, size_t pos, size_t len)
-    : cstr_(0), len_(0)
-{
-    size_t strlen = str.size();
-    pos = min(pos, strlen);
-    len = min(strlen - pos, len);
-    if (!len) return;
-    memcpy(allocate(len), str.c_str() + pos, len);
-}
-
-inline
-String& String::operator = (const std::string& str)
-{
-    deallocate();
-    size_t len = str.size();
-    if (len) memcpy(allocate(len), str.c_str(), len);
-    return *this;
-}
-
-inline
-String& String::operator += (const std::string& str)
-{
-    *this = *this + str;
-    return *this;
-}
-
-inline
-String::operator std::string() const
-{
-    return std::string(cstr_, len_);
-}
-
-inline
-String operator + (const String& lhs, const std::string& rhs)
-{
-    String s;
-    size_t rhslen = rhs.size();
-    s.allocate(lhs.len_ + rhslen);
-    if (lhs.len_) memcpy(s.cstr_, lhs.cstr_, lhs.len_);
-    if (rhslen) memcpy(s.cstr_ + lhs.len_, rhs.c_str(), rhslen);
-    return s;
-}
-
-inline
-String operator + (const std::string& lhs, const String& rhs)
-{
-    String s;
-    size_t lhslen = lhs.size();
-    s.allocate(lhslen + rhs.len_);
-    if (lhslen) memcpy(s.cstr_, lhs.c_str(), lhslen);
-    if (rhs.len_) memcpy(s.cstr_ + lhslen, rhs.cstr_, rhs.len_);
-    return s;
-}
-
 inline
 FileNode::operator std::string() const
 {

modules/core/include/opencv2/core/persistence.hpp

@@ -576,7 +576,6 @@ public:
     //! returns the node content as double
     operator double() const;
     //! returns the node content as text string
-    operator String() const;
     operator std::string() const;
 
     //! returns pointer to the underlying file node
@@ -1334,7 +1333,6 @@ inline const CvFileNode* FileNode::operator* () const { return node; }
 inline FileNode::operator int() const    { int value;    read(*this, value, 0);     return value; }
 inline FileNode::operator float() const  { float value;  read(*this, value, 0.f);   return value; }
 inline FileNode::operator double() const { double value; read(*this, value, 0.);    return value; }
-inline FileNode::operator String() const { String value; read(*this, value, value); return value; }
 inline double FileNode::real() const  { return double(*this); }
 inline String FileNode::string() const { return String(*this); }
 inline Mat FileNode::mat() const { Mat value; read(*this, value, value);    return value; }
@@ -1343,7 +1341,6 @@ inline FileNodeIterator FileNode::end() const   { return FileNodeIterator(fs, no
 inline void FileNode::readRaw( const String& fmt, uchar* vec, size_t len ) const { begin().readRaw( fmt, vec, len ); }
 inline FileNode FileNodeIterator::operator *() const  { return FileNode(fs, (const CvFileNode*)(const void*)reader.ptr); }
 inline FileNode FileNodeIterator::operator ->() const { return FileNode(fs, (const CvFileNode*)(const void*)reader.ptr); }
-inline String::String(const FileNode& fn): cstr_(0), len_(0) { read(fn, *this, *this); }
 
 //! @endcond
 

modules/core/include/opencv2/core/utility.hpp

@@ -1053,15 +1053,6 @@ template<typename _Tp, size_t fixed_size> inline size_t
 AutoBuffer<_Tp, fixed_size>::size() const
 { return sz; }
 
-template<> inline std::string CommandLineParser::get<std::string>(int index, bool space_delete) const
-{
-    return get<String>(index, space_delete);
-}
-template<> inline std::string CommandLineParser::get<std::string>(const String& name, bool space_delete) const
-{
-    return get<String>(name, space_delete);
-}
-
 //! @endcond
 
 

modules/core/src/stl.cpp

@@ -43,27 +43,3 @@
 
 
 #include "precomp.hpp"
-
-char* cv::String::allocate(size_t len)
-{
-    size_t totalsize = alignSize(len + 1, (int)sizeof(int));
-    int* data = (int*)cv::fastMalloc(totalsize + sizeof(int));
-    data[0] = 1;
-    cstr_ = (char*)(data + 1);
-    len_ = len;
-    cstr_[len] = 0;
-    return cstr_;
-}
-
-
-void cv::String::deallocate()
-{
-    int* data = (int*)cstr_;
-    len_ = 0;
-    cstr_ = 0;
-
-    if(data && 1 == CV_XADD(data-1, -1))
-    {
-        cv::fastFree(data-1);
-    }
-}

modules/core/src/system.cpp

@@ -1953,7 +1953,9 @@ public:
         ippFeatures = cpuFeatures;
 
         const char* pIppEnv = getenv("OPENCV_IPP");
-        cv::String env = pIppEnv;
+        cv::String env;
+        if(pIppEnv != NULL)
+            env = pIppEnv;
         if(env.size())
         {
 #if IPP_VERSION_X100 >= 201703

modules/cudalegacy/src/cuda/NCVHaarObjectDetection.cu

@@ -2388,7 +2388,7 @@ NCVStatus ncvHaarGetClassifierSize(const cv::String &filename, Ncv32u &numStages
     NCVStatus ncvStat;
 
     cv::String fext = filename.substr(filename.find_last_of(".") + 1);
-    fext = fext.toLowerCase();
+    std::transform(fext.begin(), fext.end(), fext.begin(), ::tolower);
 
     if (fext == "nvbin")
     {
@@ -2446,7 +2446,7 @@ NCVStatus ncvHaarLoadFromFile_host(const cv::String &filename,
     NCVStatus ncvStat;
 
     cv::String fext = filename.substr(filename.find_last_of(".") + 1);
-    fext = fext.toLowerCase();
+    std::transform(fext.begin(), fext.end(), fext.begin(), ::tolower);
 
     std::vector<HaarStage64> haarStages;
     std::vector<HaarClassifierNode128> haarNodes;

modules/cudaobjdetect/src/cascadeclassifier.cpp

@@ -809,7 +809,7 @@ namespace
 Ptr<cuda::CascadeClassifier> cv::cuda::CascadeClassifier::create(const String& filename)
 {
     String fext = filename.substr(filename.find_last_of(".") + 1);
-    fext = fext.toLowerCase();
+    std::transform(fext.begin(), fext.end(), fext.begin(), ::tolower);
 
     if (fext == "nvbin")
     {