diff options
author | Monty Brandenberg <monty@lindenlab.com> | 2012-04-23 16:19:39 -0400 |
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committer | Monty Brandenberg <monty@lindenlab.com> | 2012-04-23 16:19:39 -0400 |
commit | 5611cb6d476540e6a1c654c1f9acdce2787b3505 (patch) | |
tree | e35afc4aa33ae00e71679ba3ccfead0de563843d /indra/llcorehttp/bufferarray.cpp | |
parent | b187aeb8f177bd76e792652e773617beff18b47b (diff) |
Okay, imported the core-http library and got it compiling suspiciously easily.
The unit/integration tests don't work yet as I'm still battling cmake/autobuild
as usual but first milestone passed.
Diffstat (limited to 'indra/llcorehttp/bufferarray.cpp')
-rw-r--r-- | indra/llcorehttp/bufferarray.cpp | 281 |
1 files changed, 281 insertions, 0 deletions
diff --git a/indra/llcorehttp/bufferarray.cpp b/indra/llcorehttp/bufferarray.cpp new file mode 100644 index 0000000000..4c20350b13 --- /dev/null +++ b/indra/llcorehttp/bufferarray.cpp @@ -0,0 +1,281 @@ +/** + * @file bufferarray.cpp + * @brief Implements the BufferArray scatter/gather buffer + * + * $LicenseInfo:firstyear=2012&license=viewerlgpl$ + * Second Life Viewer Source Code + * Copyright (C) 2012, Linden Research, Inc. + * + * This library 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; + * version 2.1 of the License only. + * + * This library 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + * + * Linden Research, Inc., 945 Battery Street, San Francisco, CA 94111 USA + * $/LicenseInfo$ + */ + +#include "bufferarray.h" + + +namespace LLCore +{ + + +// ================================== +// BufferArray::Block Declaration +// ================================== + +class BufferArray::Block +{ +public: + ~Block(); + + void operator delete(void *); + void operator delete(void *, size_t len); + +protected: + Block(size_t len); + + Block(const Block &); // Not defined + void operator=(const Block &); // Not defined + + // Allocate the block with the additional space for the + // buffered data at the end of the object. + void * operator new(size_t len, size_t addl_len); + +public: + // Only public entry to get a block. + static Block * alloc(size_t len); + +public: + size_t mLen; + + // *NOTE: Must be last member of the object. We'll + // overallocate as requested via operator new and index + // into the array at will. + char mData[1]; +}; + + +// ================================== +// BufferArray Definitions +// ================================== + + +BufferArray::BufferArray() + : LLCoreInt::RefCounted(true), + mPos(0), + mLen(0) +{} + + +BufferArray::~BufferArray() +{ + for (container_t::iterator it(mBlocks.begin()); + it != mBlocks.end(); + ++it) + { + delete *it; + *it = NULL; + } + mBlocks.clear(); +} + + +size_t BufferArray::append(const char * src, size_t len) +{ + if (len) + { + if (mBlocks.size() >= mBlocks.capacity()) + { + mBlocks.reserve(mBlocks.size() + 5); + } + Block * block = Block::alloc(len); + memcpy(block->mData, src, len); + mBlocks.push_back(block); + mLen += len; + mPos = mLen; + } + return len; +} + + +char * BufferArray::appendBufferAlloc(size_t len) +{ + // If someone asks for zero-length, we give them a valid pointer. + if (mBlocks.size() >= mBlocks.capacity()) + { + mBlocks.reserve(mBlocks.size() + 5); + } + Block * block = Block::alloc(len); + mBlocks.push_back(block); + mLen += len; + mPos = mLen; + return block->mData; +} + + +size_t BufferArray::seek(size_t pos) +{ + if (pos > mLen) + pos = mLen; + mPos = pos; + return mPos; +} + + +size_t BufferArray::read(char * dst, size_t len) +{ + size_t result(0), offset(0); + size_t len_limit(mLen - mPos); + len = std::min(len, len_limit); + + if (mPos >= mLen || 0 == len) + return 0; + + const int block_limit(mBlocks.size()); + int block_start(findBlock(mPos, &offset)); + if (block_start < 0) + return 0; + + do + { + Block & block(*mBlocks[block_start]); + size_t block_limit(block.mLen - offset); + size_t block_len(std::min(block_limit, len)); + + memcpy(dst, &block.mData[offset], block_len); + result += block_len; + len -= block_len; + dst += block_len; + offset = 0; + ++block_start; + } + while (len && block_start < block_limit); + + mPos += result; + return result; +} + + +size_t BufferArray::write(const char * src, size_t len) +{ + size_t result(0), offset(0); + if (mPos > mLen || 0 == len) + return 0; + + const int block_limit(mBlocks.size()); + int block_start(findBlock(mPos, &offset)); + + if (block_start >= 0) + { + // Some or all of the write will be on top of + // existing data. + do + { + Block & block(*mBlocks[block_start]); + size_t block_limit(block.mLen - offset); + size_t block_len(std::min(block_limit, len)); + + memcpy(&block.mData[offset], src, block_len); + result += block_len; + len -= block_len; + src += block_len; + offset = 0; + ++block_start; + } + while (len && block_start < block_limit); + } + mPos += result; + + if (len) + { + // Some or all of the remaining write data will + // be an append. + result += append(src, len); + } + + return result; +} + + +int BufferArray::findBlock(size_t pos, size_t * ret_offset) +{ + *ret_offset = 0; + if (pos >= mLen) + return -1; // Doesn't exist + + const int block_limit(mBlocks.size()); + for (int i(0); i < block_limit; ++i) + { + if (pos < mBlocks[i]->mLen) + { + *ret_offset = pos; + return i; + } + pos -= mBlocks[i]->mLen; + } + + // Shouldn't get here but... + return -1; +} + + +// ================================== +// BufferArray::Block Definitions +// ================================== + + +BufferArray::Block::Block(size_t len) + : mLen(len) +{ + memset(mData, 0, len); +} + + +BufferArray::Block::~Block() +{ + mLen = 0; +} + + +void * BufferArray::Block::operator new(size_t len, size_t addl_len) +{ + void * mem = new char[len + addl_len + sizeof(void *)]; + return mem; +} + + +void BufferArray::Block::operator delete(void * mem) +{ + char * cmem = static_cast<char *>(mem); + delete [] cmem; +} + + +void BufferArray::Block::operator delete(void * mem, size_t) +{ + operator delete(mem); +} + + +BufferArray::Block * BufferArray::Block::alloc(size_t len) +{ + Block * block = new (len) Block(len); + return block; +} + + +} // end namespace LLCore + + |