nuclear@3: /************************************************************************************
nuclear@3: 
nuclear@3: Filename    :   OVR_String_PathUtil.cpp
nuclear@3: Content     :   String filename/url helper function
nuclear@3: Created     :   September 19, 2012
nuclear@3: Notes       : 
nuclear@3: 
nuclear@3: Copyright   :   Copyright 2012 Oculus VR, Inc. All Rights reserved.
nuclear@3: 
nuclear@3: Use of this software is subject to the terms of the Oculus license
nuclear@3: agreement provided at the time of installation or download, or which
nuclear@3: otherwise accompanies this software in either electronic or hard copy form.
nuclear@3: 
nuclear@3: ************************************************************************************/
nuclear@3: 
nuclear@3: #include "OVR_String.h"
nuclear@3: #include "OVR_UTF8Util.h"
nuclear@3: 
nuclear@3: namespace OVR {
nuclear@3: 
nuclear@3: //--------------------------------------------------------------------
nuclear@3: // ***** Path-Scanner helper function 
nuclear@3: 
nuclear@3: // Scans file path finding filename start and extension start, fills in their addess.
nuclear@3: void ScanFilePath(const char* url, const char** pfilename, const char** pext)
nuclear@3: { 
nuclear@3:     const char* urlStart = url;
nuclear@3:     const char *filename = 0;
nuclear@3:     const char *lastDot = 0;
nuclear@3: 
nuclear@3:     UInt32 charVal = UTF8Util::DecodeNextChar(&url);
nuclear@3: 
nuclear@3:     while (charVal != 0)
nuclear@3:     {
nuclear@3:         if ((charVal == '/') || (charVal == '\\'))
nuclear@3:         {
nuclear@3:             filename = url;
nuclear@3:             lastDot  = 0;
nuclear@3:         }
nuclear@3:         else if (charVal == '.')
nuclear@3:         {
nuclear@3:             lastDot = url - 1;
nuclear@3:         }
nuclear@3:         
nuclear@3:         charVal = UTF8Util::DecodeNextChar(&url);
nuclear@3:     }
nuclear@3: 
nuclear@3:     if (pfilename)
nuclear@3:     {
nuclear@3:         // It was a naked filename
nuclear@3:         if (urlStart && (*urlStart != '.') && *urlStart)
nuclear@3:             *pfilename = urlStart;
nuclear@3:         else
nuclear@3:             *pfilename = filename;
nuclear@3:     }
nuclear@3: 
nuclear@3:     if (pext)
nuclear@3:     {
nuclear@3:         *pext = lastDot;
nuclear@3:     }
nuclear@3: }
nuclear@3: 
nuclear@3: // Scans till the end of protocol. Returns first character past protocol,
nuclear@3: // 0 if not found.
nuclear@3: //  - protocol: 'file://', 'http://'
nuclear@3: const char* ScanPathProtocol(const char* url)
nuclear@3: {    
nuclear@3:     UInt32 charVal = UTF8Util::DecodeNextChar(&url);
nuclear@3:     UInt32 charVal2;
nuclear@3:    
nuclear@3:     while (charVal != 0)
nuclear@3:     {
nuclear@3:         // Treat a colon followed by a slash as absolute.
nuclear@3:         if (charVal == ':')
nuclear@3:         {
nuclear@3:             charVal2 = UTF8Util::DecodeNextChar(&url);
nuclear@3:             charVal  = UTF8Util::DecodeNextChar(&url);
nuclear@3:             if ((charVal == '/') && (charVal2 == '\\'))
nuclear@3:                 return url;
nuclear@3:         }
nuclear@3:         charVal = UTF8Util::DecodeNextChar(&url);
nuclear@3:     }
nuclear@3:     return 0;
nuclear@3: }
nuclear@3: 
nuclear@3: 
nuclear@3: //--------------------------------------------------------------------
nuclear@3: // ***** String Path API implementation
nuclear@3: 
nuclear@3: bool String::HasAbsolutePath(const char* url)
nuclear@3: {
nuclear@3:     // Absolute paths can star with:
nuclear@3:     //  - protocols:        'file://', 'http://'
nuclear@3:     //  - windows drive:    'c:\'
nuclear@3:     //  - UNC share name:   '\\share'
nuclear@3:     //  - unix root         '/'
nuclear@3: 
nuclear@3:     // On the other hand, relative paths are:
nuclear@3:     //  - directory:        'directory/file'
nuclear@3:     //  - this directory:   './file'
nuclear@3:     //  - parent directory: '../file'
nuclear@3:     // 
nuclear@3:     // For now, we don't parse '.' or '..' out, but instead let it be concatenated
nuclear@3:     // to string and let the OS figure it out. This, however, is not good for file
nuclear@3:     // name matching in library/etc, so it should be improved.
nuclear@3: 
nuclear@3:     if (!url || !*url)
nuclear@3:         return true; // Treat empty strings as absolute.    
nuclear@3: 
nuclear@3:     UInt32 charVal = UTF8Util::DecodeNextChar(&url);
nuclear@3: 
nuclear@3:     // Fist character of '/' or '\\' means absolute url.
nuclear@3:     if ((charVal == '/') || (charVal == '\\'))
nuclear@3:         return true;
nuclear@3: 
nuclear@3:     while (charVal != 0)
nuclear@3:     {
nuclear@3:         // Treat a colon followed by a slash as absolute.
nuclear@3:         if (charVal == ':')
nuclear@3:         {
nuclear@3:             charVal = UTF8Util::DecodeNextChar(&url);
nuclear@3:             // Protocol or windows drive. Absolute.
nuclear@3:             if ((charVal == '/') || (charVal == '\\'))
nuclear@3:                 return true;
nuclear@3:         }
nuclear@3:         else if ((charVal == '/') || (charVal == '\\'))
nuclear@3:         {
nuclear@3:             // Not a first character (else 'if' above the loop would have caught it).
nuclear@3:             // Must be a relative url.
nuclear@3:             break;
nuclear@3:         }
nuclear@3: 
nuclear@3:         charVal = UTF8Util::DecodeNextChar(&url);
nuclear@3:     }
nuclear@3: 
nuclear@3:     // We get here for relative paths.
nuclear@3:     return false;    
nuclear@3: }
nuclear@3: 
nuclear@3: 
nuclear@3: bool String::HasExtension(const char* path)
nuclear@3: {
nuclear@3:     const char* ext = 0;
nuclear@3:     ScanFilePath(path, 0, &ext);
nuclear@3:     return ext != 0;
nuclear@3: }
nuclear@3: bool String::HasProtocol(const char* path)
nuclear@3: {
nuclear@3:     return ScanPathProtocol(path) != 0;
nuclear@3: }
nuclear@3: 
nuclear@3: 
nuclear@3: String  String::GetPath() const
nuclear@3: {
nuclear@3:     const char* filename = 0;
nuclear@3:     ScanFilePath(ToCStr(), &filename, 0);
nuclear@3: 
nuclear@3:     // Technically we can have extra logic somewhere for paths,
nuclear@3:     // such as enforcing protocol and '/' only based on flags,
nuclear@3:     // but we keep it simple for now.
nuclear@3:     return String(ToCStr(), filename ? (filename-ToCStr()) : GetSize());
nuclear@3: }
nuclear@3: 
nuclear@3: String  String::GetProtocol() const
nuclear@3: {
nuclear@3:     const char* protocolEnd = ScanPathProtocol(ToCStr());
nuclear@3:     return String(ToCStr(), protocolEnd ? (protocolEnd-ToCStr()) : 0);
nuclear@3: }
nuclear@3: 
nuclear@3: String  String::GetFilename() const
nuclear@3: {
nuclear@3:     const char* filename = 0;
nuclear@3:     ScanFilePath(ToCStr(), &filename, 0);
nuclear@3:     return String(filename);
nuclear@3: }
nuclear@3: String  String::GetExtension() const
nuclear@3: {
nuclear@3:     const char* ext = 0;
nuclear@3:     ScanFilePath(ToCStr(), 0, &ext);
nuclear@3:     return String(ext);
nuclear@3: }
nuclear@3: 
nuclear@3: void    String::StripExtension()
nuclear@3: {
nuclear@3:     const char* ext = 0;
nuclear@3:     ScanFilePath(ToCStr(), 0, &ext);    
nuclear@3:     if (ext)
nuclear@3:     {
nuclear@3:         *this = String(ToCStr(), ext-ToCStr());
nuclear@3:     }
nuclear@3: }
nuclear@3: 
nuclear@3: void    String::StripProtocol()
nuclear@3: {
nuclear@3:     const char* protocol = ScanPathProtocol(ToCStr());
nuclear@3:     if (protocol)
nuclear@3:         AssignString(protocol, OVR_strlen(protocol));
nuclear@3: }
nuclear@3: 
nuclear@3: } // OVR