raze-gles/libraries/music_common/fileio.h
2019-11-10 23:58:51 +01:00

380 lines
9.1 KiB
C++

/*
The common sound font reader interface. Used by GUS, Timidity++ and WildMidi
backends for reading sound font configurations.
The FileInterface is also used by streaming sound formats.
Copyright (C) 2019 Christoph Oelckers
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#pragma once
#include <stdio.h>
#include <string.h>
#include <vector>
#include <string>
#if defined _WIN32 && !defined _WINDOWS_ // only define this if windows.h is not included.
// I'd rather not include Windows.h for just this. This header is not supposed to pollute everything it touches.
extern "C" __declspec(dllimport) int __stdcall MultiByteToWideChar(unsigned CodePage, unsigned long dwFlags, const char* lpMultiByteStr, int cbMultiByte, const wchar_t* lpWideCharStr, int cchWideChar);
enum
{
CP_UTF8 = 65001
};
#endif
namespace MusicIO
{
//==========================================================================
//
// This class defines a common file wrapper interface which allows these
// libraries to work with any kind of file access API, e.g. stdio (provided below),
// Win32, POSIX, iostream or custom implementations (like GZDoom's FileReader.)
//
//==========================================================================
struct FileInterface
{
std::string filename;
long length = -1;
// It's really too bad that the using code requires long instead of size_t.
// Fortunately 2GB files are unlikely to come by here.
protected:
//
virtual ~FileInterface() {}
public:
virtual char* gets(char* buff, int n) = 0;
virtual long read(void* buff, int32_t size, int32_t nitems) = 0;
long read(void* buff, int32_t size) { return read(buff, 1, size); }
virtual long seek(long offset, int whence) = 0;
virtual long tell() = 0;
virtual void close()
{
delete this;
}
long filelength()
{
if (length == -1)
{
long pos = tell();
seek(0, SEEK_END);
length = tell();
seek(pos, SEEK_SET);
}
return length;
}
};
//==========================================================================
//
// Inplementation of the FileInterface for stdio's FILE*.
//
//==========================================================================
struct StdioFileReader : public FileInterface
{
FILE* f = nullptr;
~StdioFileReader()
{
if (f) fclose(f);
}
char* gets(char* buff, int n) override
{
if (!f) return nullptr;
return fgets(buff, n, f);
}
long read(void* buff, int32_t size, int32_t nitems) override
{
if (!f) return 0;
return (long)fread(buff, size, nitems, f);
}
long seek(long offset, int whence) override
{
if (!f) return 0;
return fseek(f, offset, whence);
}
long tell() override
{
if (!f) return 0;
return ftell(f);
}
};
//==========================================================================
//
// Inplementation of the FileInterface for a block of memory
//
//==========================================================================
struct MemoryReader : public FileInterface
{
const uint8_t *mData;
long mLength;
long mPos;
MemoryReader(const uint8_t *data, long length)
: mData(data), mLength(length), mPos(0)
{
}
char* gets(char* strbuf, int len) override
{
if (len > mLength - mPos) len = mLength - mPos;
if (len <= 0) return NULL;
char *p = strbuf;
while (len > 1)
{
if (mData[mPos] == 0)
{
mPos++;
break;
}
if (mData[mPos] != '\r')
{
*p++ = mData[mPos];
len--;
if (mData[mPos] == '\n')
{
mPos++;
break;
}
}
mPos++;
}
if (p == strbuf) return nullptr;
*p++ = 0;
return strbuf;
}
long read(void* buff, int32_t size, int32_t nitems) override
{
long len = long(size) * nitems;
if (len > mLength - mPos) len = mLength - mPos;
if (len < 0) len = 0;
memcpy(buff, mData + mPos, len);
mPos += len;
return len / size;
}
long seek(long offset, int whence) override
{
switch (whence)
{
case SEEK_CUR:
offset += mPos;
break;
case SEEK_END:
offset += mLength;
break;
}
if (offset < 0 || offset > mLength) return -1;
mPos = offset;
return 0;
}
long tell() override
{
return mPos;
}
protected:
MemoryReader() {}
};
//==========================================================================
//
// Inplementation of the FileInterface for an std::vector owned by the reader
//
//==========================================================================
struct VectorReader : public MemoryReader
{
std::vector<uint8_t> mVector;
template <class getFunc>
VectorReader(getFunc getter) // read contents to a buffer and return a reader to it
{
getter(mVector);
mData = mVector.data();
mLength = (long)mVector.size();
mPos = 0;
}
};
//==========================================================================
//
// The follpwing two functions are needed to allow using UTF-8 in the file interface.
// fopen on Windows is only safe for ASCII,
//
//==========================================================================
#ifdef _WIN32
inline std::wstring wideString(const char *filename)
{
std::wstring filePathW;
auto len = strlen(filename);
filePathW.resize(len);
int newSize = MultiByteToWideChar(CP_UTF8, 0, filename, (int)len, const_cast<wchar_t*>(filePathW.c_str()), (int)len);
filePathW.resize(newSize);
return filePathW;
}
#endif
inline FILE* utf8_fopen(const char* filename, const char *mode)
{
#ifndef _WIN32
return fopen(filename, mode);
#else
auto fn = wideString(filename);
auto mo = wideString(mode);
return _wfopen(fn.c_str(), mo.c_str());
#endif
}
inline bool fileExists(const char *fn)
{
FILE *f = utf8_fopen(fn, "rb");
if (!f) return false;
fclose(f);
return true;
}
//==========================================================================
//
// This class providea a framework for reading sound fonts.
// This is needed when the sound font data is not read from
// the file system. e.g. zipped GUS patch sets.
//
//==========================================================================
class SoundFontReaderInterface
{
public:
virtual ~SoundFontReaderInterface() {}
virtual struct FileInterface* open_file(const char* fn) = 0;
virtual void add_search_path(const char* path) = 0;
};
//==========================================================================
//
// A basic sound font reader for reading data from the file system.
//
//==========================================================================
class FileSystemSoundFontReader : public SoundFontReaderInterface
{
protected:
std::vector<std::string> mPaths;
std::string mBaseFile;
bool mAllowAbsolutePaths;
bool IsAbsPath(const char *name)
{
if (name[0] == '/' || name[0] == '\\') return true;
#ifdef _WIN32
/* [A-Za-z]: (for Windows) */
if (isalpha(name[0]) && name[1] == ':') return true;
#endif /* _WIN32 */
return 0;
}
public:
FileSystemSoundFontReader(const char *configfilename, bool allowabs = false)
{
// Note that this does not add the directory the base file is in to the search path!
// The caller of this has to do it themselves!
mBaseFile = configfilename;
mAllowAbsolutePaths = allowabs;
}
struct FileInterface* open_file(const char* fn) override
{
FILE *f = nullptr;
std::string fullname;
if (!fn)
{
f = utf8_fopen(mBaseFile.c_str(), "rt");
fullname = mBaseFile;
}
else
{
if (!IsAbsPath(fn))
{
for(int i = (int)mPaths.size()-1; i>=0; i--)
{
fullname = mPaths[i] + fn;
f = utf8_fopen(fullname.c_str(), "rt");
break;
}
}
if (!f) f = fopen(fn, "rt");
}
if (!f) return nullptr;
auto tf = new StdioFileReader;
tf->f = f;
tf->filename = fullname;
return tf;
}
void add_search_path(const char* path) override
{
std::string p = path;
if (p.back() != '/' && p.back() != '\\') p += '/'; // always let it end with a slash.
mPaths.push_back(p);
}
};
//==========================================================================
//
// This reader exists to trick Timidity config readers into accepting
// a loose SF2 file by providing a fake config pointing to the given file.
//
//==========================================================================
class SF2Reader : public FileSystemSoundFontReader
{
std::string mMainConfigForSF2;
public:
SF2Reader(const char *filename)
: FileSystemSoundFontReader(filename)
{
mMainConfigForSF2 = "soundfont \"" + mBaseFile + "\"\n";
}
struct FileInterface* open_file(const char* fn) override
{
if (fn == nullptr)
{
return new MemoryReader((uint8_t*)mMainConfigForSF2.c_str(), (long)mMainConfigForSF2.length());
}
else return FileSystemSoundFontReader::open_file(fn);
}
};
}