1 //===- MSFCommon.cpp - Common types and functions for MSF files -----------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "llvm/DebugInfo/MSF/MSFCommon.h" 10 #include "llvm/DebugInfo/MSF/MSFError.h" 11 #include "llvm/Support/Endian.h" 12 #include "llvm/Support/Error.h" 13 #include <cstdint> 14 #include <cstring> 15 16 using namespace llvm; 17 using namespace llvm::msf; 18 19 Error llvm::msf::validateSuperBlock(const SuperBlock &SB) { 20 // Check the magic bytes. 21 if (std::memcmp(SB.MagicBytes, Magic, sizeof(Magic)) != 0) 22 return make_error<MSFError>(msf_error_code::invalid_format, 23 "MSF magic header doesn't match"); 24 25 if (!isValidBlockSize(SB.BlockSize)) 26 return make_error<MSFError>(msf_error_code::invalid_format, 27 "Unsupported block size."); 28 29 // We don't support directories whose sizes aren't a multiple of four bytes. 30 if (SB.NumDirectoryBytes % sizeof(support::ulittle32_t) != 0) 31 return make_error<MSFError>(msf_error_code::invalid_format, 32 "Directory size is not multiple of 4."); 33 34 // The number of blocks which comprise the directory is a simple function of 35 // the number of bytes it contains. 36 uint64_t NumDirectoryBlocks = 37 bytesToBlocks(SB.NumDirectoryBytes, SB.BlockSize); 38 39 // The directory, as we understand it, is a block which consists of a list of 40 // block numbers. It is unclear what would happen if the number of blocks 41 // couldn't fit on a single block. 42 if (NumDirectoryBlocks > SB.BlockSize / sizeof(support::ulittle32_t)) 43 return make_error<MSFError>(msf_error_code::invalid_format, 44 "Too many directory blocks."); 45 46 if (SB.BlockMapAddr == 0) 47 return make_error<MSFError>(msf_error_code::invalid_format, 48 "Block 0 is reserved"); 49 50 if (SB.BlockMapAddr >= SB.NumBlocks) 51 return make_error<MSFError>(msf_error_code::invalid_format, 52 "Block map address is invalid."); 53 54 if (SB.FreeBlockMapBlock != 1 && SB.FreeBlockMapBlock != 2) 55 return make_error<MSFError>( 56 msf_error_code::invalid_format, 57 "The free block map isn't at block 1 or block 2."); 58 59 return Error::success(); 60 } 61 62 MSFStreamLayout llvm::msf::getFpmStreamLayout(const MSFLayout &Msf, 63 bool IncludeUnusedFpmData, 64 bool AltFpm) { 65 MSFStreamLayout FL; 66 uint32_t NumFpmIntervals = 67 getNumFpmIntervals(Msf, IncludeUnusedFpmData, AltFpm); 68 69 uint32_t FpmBlock = AltFpm ? Msf.alternateFpmBlock() : Msf.mainFpmBlock(); 70 71 for (uint32_t I = 0; I < NumFpmIntervals; ++I) { 72 FL.Blocks.push_back(support::ulittle32_t(FpmBlock)); 73 FpmBlock += msf::getFpmIntervalLength(Msf); 74 } 75 76 if (IncludeUnusedFpmData) 77 FL.Length = NumFpmIntervals * Msf.SB->BlockSize; 78 else 79 FL.Length = divideCeil(Msf.SB->NumBlocks, 8); 80 81 return FL; 82 } 83