From 05f7e9b4c6f804102f261517c8ecdd338e1f67d3 Mon Sep 17 00:00:00 2001 From: Mikko Rasa Date: Fri, 6 Jul 2012 23:25:32 +0300 Subject: [PATCH] Store an array of separators alongside with the path string --- source/fs/path.cpp | 120 ++++++++++++++++++++++----------------------- source/fs/path.h | 21 +++++--- 2 files changed, 72 insertions(+), 69 deletions(-) diff --git a/source/fs/path.cpp b/source/fs/path.cpp index b8b7c22..9380527 100644 --- a/source/fs/path.cpp +++ b/source/fs/path.cpp @@ -53,10 +53,7 @@ unsigned Path::size() const if(path.size()==1 && path[0]==DIRSEP) return 1; - unsigned count = 1; - for(string::const_iterator i=path.begin(); i!=path.end(); ++i) - if(*i==DIRSEP) ++count; - return count; + return separators.size()+1; } bool Path::is_absolute() const @@ -109,16 +106,26 @@ void Path::add_component(const string &comp) { // Replace the path with the root directory #ifdef WIN32 - unsigned slash = path.find(DIRSEP); + string::size_type slash = (separators.empty() ? string::npos : separators.front()); if(is_windows_drive(path.substr(0, slash))) + { path = path.substr(0, 2); + separators.clear(); + } else #endif - path = comp; + { + path = comp; + separators.clear(); + separators.push_back(0); + } } #ifdef WIN32 else if(is_windows_drive(comp)) + { path = comp; + separators.clear(); + } #endif else if(comp=="..") { @@ -133,22 +140,21 @@ void Path::add_component(const string &comp) #endif else { - string::size_type slash = path.rfind(DIRSEP); - string::size_type start = (slash==string::npos ? 0 : slash+1); + string::size_type start = (separators.empty() ? 0 : separators.back()+1); if(!path.compare(start, string::npos, "..")) { // If the last component already is a .., add another + separators.push_back(path.size()); path += DIRSEP; path += comp; } - else if(slash==string::npos) + else if(separators.empty()) path = "."; else { - if(slash==0) - slash = 1; // Otherwise, erase the last component - path.erase(slash, string::npos); + path.erase(separators.back(), string::npos); + separators.pop_back(); } } } @@ -157,7 +163,10 @@ void Path::add_component(const string &comp) if(comp!="." && path.empty()) path = "."; if(path.size()>1 || (path.size()==1 && path[0]!=DIRSEP)) + { + separators.push_back(path.size()); path += DIRSEP; + } path += comp; } } @@ -210,71 +219,58 @@ bool Path::operator>(const Path &other) const #endif } -Path::Iterator Path::begin() const -{ - return Iterator(*this); -} -Path::Iterator Path::end() const -{ - Iterator i(*this); - i.start = i.end = std::string::npos; - return i; -} - - -Path::Iterator::Iterator(const Path &p): +Path::Iterator::Iterator(const Path &p, bool e): path(&p), - start(0) -{ - if(path->path.empty()) - start = end = string::npos; - else if(path->path[0]==DIRSEP) - end = 1; -#ifdef WIN32 - else if(path->path.size()>2 && path->path[2]==DIRSEP && is_windows_drive(path->path.substr(0, 2))) - end = 2; -#endif - else - end = path->path.find(DIRSEP); -} + iter(e ? path->separators.end() : path->separators.begin()), + end(e || path->path.empty()) +{ } Path::Iterator &Path::Iterator::operator++() { - start = end; - if(start>=path->path.size()) - return *this; - if(path->path[start]==DIRSEP) - ++start; - end = path->path.find(DIRSEP, start); + if(iter==path->separators.end()) + end = true; + else + { + ++iter; + if(path->path.size()==1 && path->separators.size()==1) + end = true; + } return *this; } Path::Iterator &Path::Iterator::operator--() { - if(start==0) - return *this; - - end = start; - if(end>1 && endpath.size() && path->path[end]!=DIRSEP) - --end; - - start = path->path.rfind(DIRSEP, end-1); - if(start==string::npos) - start = 0; - else if(startpath.size()==1 && path->separators.size()==1) + --iter; + } + else if(iter!=path->separators.begin()) + --iter; return *this; } string Path::Iterator::operator*() const { - if(start>=path->path.size()) - return string(); - if(start==end) - return string(); - return path->path.substr(start, end-start); + if(end) + throw logic_error("Path::Iterator::operator*"); + + string::size_type start = 0; + if(iter!=path->separators.begin()) + { + PositionArray::const_iterator prev = iter; + start = *--prev+1; + } + + string::size_type slash = string::npos; + if(iter!=path->separators.end()) + slash = *iter; + + if(slash==0) + return path->path.substr(start, 1); + return path->path.substr(start, slash-start); } } // namespace FS diff --git a/source/fs/path.h b/source/fs/path.h index d515d78..9bc93f6 100644 --- a/source/fs/path.h +++ b/source/fs/path.h @@ -3,6 +3,7 @@ #include #include +#include namespace Msp { namespace FS { @@ -23,26 +24,32 @@ paths always begin with a single "." component or a sequence ".." components. */ class Path { +private: + typedef std::vector PositionArray; + public: class Iterator { - friend class Path; - private: const Path *path; - std::string::size_type start, end; + PositionArray::const_iterator iter; + bool end; - Iterator(const Path &); + Iterator(const Path &, bool = false); public: + static Iterator at_begin(const Path &p) { return Iterator(p); } + static Iterator at_end(const Path &p) { return Iterator(p, true); } + Iterator &operator++(); Iterator &operator--(); std::string operator*() const; - bool operator==(const Iterator &i) const { return (start==i.start && end==i.end); } + bool operator==(const Iterator &i) const { return (iter==i.iter && end==i.end); } bool operator!=(const Iterator &i) const { return !(*this==i); } }; private: std::string path; + std::vector separators; public: Path(); @@ -86,8 +93,8 @@ public: bool operator>=(const Path &other) const { return !(*this