cog/Frameworks/OpenMPT.old/OpenMPT/common/mptStringBuffer.cpp

118 lines
2.4 KiB
C++

/*
* mptStringBuffer.cpp
* -------------------
* Purpose: Various functions for "fixing" char array strings for writing to or
* reading from module files, or for securing char arrays in general.
* Notes : (currently none)
* Authors: OpenMPT Devs
* The OpenMPT source code is released under the BSD license. Read LICENSE for more details.
*/
#include "stdafx.h"
#include "mptStringBuffer.h"
OPENMPT_NAMESPACE_BEGIN
namespace mpt
{
namespace String
{
namespace detail
{
std::string ReadStringBuffer(String::ReadWriteMode mode, const char *srcBuffer, std::size_t srcSize)
{
std::string dest;
const char *src = srcBuffer;
if(mode == nullTerminated || mode == spacePaddedNull)
{
// We assume that the last character of the source buffer is null.
if(srcSize > 0)
{
srcSize -= 1;
}
}
if(mode == nullTerminated || mode == maybeNullTerminated)
{
// Copy null-terminated string, stopping at null.
dest.assign(src, std::find(src, src + srcSize, '\0'));
} else if(mode == spacePadded || mode == spacePaddedNull)
{
// Copy string over.
dest.assign(src, src + srcSize);
// Convert null characters to spaces.
std::transform(dest.begin(), dest.end(), dest.begin(), [] (char c) -> char { return (c != '\0') ? c : ' '; });
// Trim trailing spaces.
dest = mpt::String::RTrim(dest, std::string(" "));
}
return dest;
}
void WriteStringBuffer(String::ReadWriteMode mode, char *destBuffer, const std::size_t destSize, const char *srcBuffer, const std::size_t srcSize)
{
MPT_ASSERT(destSize > 0);
const size_t maxSize = std::min(destSize, srcSize);
char *dst = destBuffer;
const char *src = srcBuffer;
// First, copy over null-terminated string.
size_t pos = maxSize;
while(pos > 0)
{
if((*dst = *src) == '\0')
{
break;
}
pos--;
dst++;
src++;
}
if(mode == nullTerminated || mode == maybeNullTerminated)
{
// Fill rest of string with nulls.
std::fill(dst, dst + destSize - maxSize + pos, '\0');
} else if(mode == spacePadded || mode == spacePaddedNull)
{
// Fill the rest of the destination string with spaces.
std::fill(dst, dst + destSize - maxSize + pos, ' ');
}
if(mode == nullTerminated || mode == spacePaddedNull)
{
// Make sure that destination is really null-terminated.
SetNullTerminator(destBuffer, destSize);
}
}
} // namespace detail
} // namespace String
} // namespace mpt
OPENMPT_NAMESPACE_END