llvm-project/llvm/lib/DebugInfo/MSF/MSFCommon.cpp

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3.1 KiB
C++

//===- MSFCommon.cpp - Common types and functions for MSF files -----------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/DebugInfo/MSF/MSFCommon.h"
#include "llvm/DebugInfo/MSF/MSFError.h"
#include "llvm/Support/Endian.h"
#include "llvm/Support/Error.h"
#include <cstdint>
#include <cstring>
using namespace llvm;
using namespace llvm::msf;
Error llvm::msf::validateSuperBlock(const SuperBlock &SB) {
// Check the magic bytes.
if (std::memcmp(SB.MagicBytes, Magic, sizeof(Magic)) != 0)
return make_error<MSFError>(msf_error_code::invalid_format,
"MSF magic header doesn't match");
if (!isValidBlockSize(SB.BlockSize))
return make_error<MSFError>(msf_error_code::invalid_format,
"Unsupported block size.");
// We don't support directories whose sizes aren't a multiple of four bytes.
if (SB.NumDirectoryBytes % sizeof(support::ulittle32_t) != 0)
return make_error<MSFError>(msf_error_code::invalid_format,
"Directory size is not multiple of 4.");
// The number of blocks which comprise the directory is a simple function of
// the number of bytes it contains.
uint64_t NumDirectoryBlocks =
bytesToBlocks(SB.NumDirectoryBytes, SB.BlockSize);
// The directory, as we understand it, is a block which consists of a list of
// block numbers. It is unclear what would happen if the number of blocks
// couldn't fit on a single block.
if (NumDirectoryBlocks > SB.BlockSize / sizeof(support::ulittle32_t))
return make_error<MSFError>(msf_error_code::invalid_format,
"Too many directory blocks.");
if (SB.BlockMapAddr == 0)
return make_error<MSFError>(msf_error_code::invalid_format,
"Block 0 is reserved");
if (SB.BlockMapAddr >= SB.NumBlocks)
return make_error<MSFError>(msf_error_code::invalid_format,
"Block map address is invalid.");
if (SB.FreeBlockMapBlock != 1 && SB.FreeBlockMapBlock != 2)
return make_error<MSFError>(
msf_error_code::invalid_format,
"The free block map isn't at block 1 or block 2.");
return Error::success();
}
MSFStreamLayout llvm::msf::getFpmStreamLayout(const MSFLayout &Msf,
bool IncludeUnusedFpmData,
bool AltFpm) {
MSFStreamLayout FL;
uint32_t NumFpmIntervals =
getNumFpmIntervals(Msf, IncludeUnusedFpmData, AltFpm);
uint32_t FpmBlock = AltFpm ? Msf.alternateFpmBlock() : Msf.mainFpmBlock();
for (uint32_t I = 0; I < NumFpmIntervals; ++I) {
FL.Blocks.push_back(support::ulittle32_t(FpmBlock));
FpmBlock += msf::getFpmIntervalLength(Msf);
}
if (IncludeUnusedFpmData)
FL.Length = NumFpmIntervals * Msf.SB->BlockSize;
else
FL.Length = divideCeil(Msf.SB->NumBlocks, 8);
return FL;
}