diff options
Diffstat (limited to 'contrib/llvm/lib/Object/Archive.cpp')
| -rw-r--r-- | contrib/llvm/lib/Object/Archive.cpp | 272 |
1 files changed, 272 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Object/Archive.cpp b/contrib/llvm/lib/Object/Archive.cpp new file mode 100644 index 0000000..c5f15ba --- /dev/null +++ b/contrib/llvm/lib/Object/Archive.cpp @@ -0,0 +1,272 @@ +//===- Archive.cpp - ar File Format implementation --------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file defines the ArchiveObjectFile class. +// +//===----------------------------------------------------------------------===// + +#include "llvm/Object/Archive.h" +#include "llvm/ADT/APInt.h" +#include "llvm/Support/Endian.h" +#include "llvm/Support/MemoryBuffer.h" + +using namespace llvm; +using namespace object; + +static const char *Magic = "!<arch>\n"; + +namespace { +struct ArchiveMemberHeader { + char Name[16]; + char LastModified[12]; + char UID[6]; + char GID[6]; + char AccessMode[8]; + char Size[10]; //< Size of data, not including header or padding. + char Terminator[2]; + + ///! Get the name without looking up long names. + StringRef getName() const { + char EndCond; + if (Name[0] == '/' || Name[0] == '#') + EndCond = ' '; + else + EndCond = '/'; + StringRef::size_type end = StringRef(Name, sizeof(Name)).find(EndCond); + if (end == StringRef::npos) + end = sizeof(Name); + assert(end <= sizeof(Name) && end > 0); + // Don't include the EndCond if there is one. + return StringRef(Name, end); + } + + uint64_t getSize() const { + APInt ret; + StringRef(Size, sizeof(Size)).getAsInteger(10, ret); + return ret.getZExtValue(); + } +}; +} + +static const ArchiveMemberHeader *ToHeader(const char *base) { + return reinterpret_cast<const ArchiveMemberHeader *>(base); +} + + +static bool isInternalMember(const ArchiveMemberHeader &amh) { + const char *internals[] = { + "/", + "//", + "#_LLVM_SYM_TAB_#" + }; + + StringRef name = amh.getName(); + for (std::size_t i = 0; i < sizeof(internals) / sizeof(*internals); ++i) { + if (name == internals[i]) + return true; + } + return false; +} + +void Archive::anchor() { } + +Archive::Child Archive::Child::getNext() const { + size_t SpaceToSkip = sizeof(ArchiveMemberHeader) + + ToHeader(Data.data())->getSize(); + // If it's odd, add 1 to make it even. + if (SpaceToSkip & 1) + ++SpaceToSkip; + + const char *NextLoc = Data.data() + SpaceToSkip; + + // Check to see if this is past the end of the archive. + if (NextLoc >= Parent->Data->getBufferEnd()) + return Child(Parent, StringRef(0, 0)); + + size_t NextSize = sizeof(ArchiveMemberHeader) + + ToHeader(NextLoc)->getSize(); + + return Child(Parent, StringRef(NextLoc, NextSize)); +} + +error_code Archive::Child::getName(StringRef &Result) const { + StringRef name = ToHeader(Data.data())->getName(); + // Check if it's a special name. + if (name[0] == '/') { + if (name.size() == 1) { // Linker member. + Result = name; + return object_error::success; + } + if (name.size() == 2 && name[1] == '/') { // String table. + Result = name; + return object_error::success; + } + // It's a long name. + // Get the offset. + APInt offset; + name.substr(1).getAsInteger(10, offset); + const char *addr = Parent->StringTable->Data.begin() + + sizeof(ArchiveMemberHeader) + + offset.getZExtValue(); + // Verify it. + if (Parent->StringTable == Parent->end_children() + || addr < (Parent->StringTable->Data.begin() + + sizeof(ArchiveMemberHeader)) + || addr > (Parent->StringTable->Data.begin() + + sizeof(ArchiveMemberHeader) + + Parent->StringTable->getSize())) + return object_error::parse_failed; + Result = addr; + return object_error::success; + } else if (name.startswith("#1/")) { + APInt name_size; + name.substr(3).getAsInteger(10, name_size); + Result = Data.substr(0, name_size.getZExtValue()); + return object_error::success; + } + // It's a simple name. + if (name[name.size() - 1] == '/') + Result = name.substr(0, name.size() - 1); + else + Result = name; + return object_error::success; +} + +uint64_t Archive::Child::getSize() const { + uint64_t size = ToHeader(Data.data())->getSize(); + // Don't include attached name. + StringRef name = ToHeader(Data.data())->getName(); + if (name.startswith("#1/")) { + APInt name_size; + name.substr(3).getAsInteger(10, name_size); + size -= name_size.getZExtValue(); + } + return size; +} + +MemoryBuffer *Archive::Child::getBuffer() const { + StringRef name; + if (getName(name)) return NULL; + int size = sizeof(ArchiveMemberHeader); + if (name.startswith("#1/")) { + APInt name_size; + name.substr(3).getAsInteger(10, name_size); + size += name_size.getZExtValue(); + } + return MemoryBuffer::getMemBuffer(Data.substr(size, getSize()), + name, + false); +} + +error_code Archive::Child::getAsBinary(OwningPtr<Binary> &Result) const { + OwningPtr<Binary> ret; + if (error_code ec = + createBinary(getBuffer(), ret)) + return ec; + Result.swap(ret); + return object_error::success; +} + +Archive::Archive(MemoryBuffer *source, error_code &ec) + : Binary(Binary::ID_Archive, source) { + // Check for sufficient magic. + if (!source || source->getBufferSize() + < (8 + sizeof(ArchiveMemberHeader) + 2) // Smallest archive. + || StringRef(source->getBufferStart(), 8) != Magic) { + ec = object_error::invalid_file_type; + return; + } + + // Get the special members. + child_iterator i = begin_children(false); + child_iterator e = end_children(); + + if (i != e) ++i; // Nobody cares about the first member. + if (i != e) { + SymbolTable = i; + ++i; + } + if (i != e) { + StringTable = i; + } + + ec = object_error::success; +} + +Archive::child_iterator Archive::begin_children(bool skip_internal) const { + const char *Loc = Data->getBufferStart() + strlen(Magic); + size_t Size = sizeof(ArchiveMemberHeader) + + ToHeader(Loc)->getSize(); + Child c(this, StringRef(Loc, Size)); + // Skip internals at the beginning of an archive. + if (skip_internal && isInternalMember(*ToHeader(Loc))) + return c.getNext(); + return c; +} + +Archive::child_iterator Archive::end_children() const { + return Child(this, StringRef(0, 0)); +} + +error_code Archive::Symbol::getName(StringRef &Result) const { + Result = + StringRef(Parent->SymbolTable->getBuffer()->getBufferStart() + StringIndex); + return object_error::success; +} + +error_code Archive::Symbol::getMember(child_iterator &Result) const { + const char *buf = Parent->SymbolTable->getBuffer()->getBufferStart(); + uint32_t member_count = *reinterpret_cast<const support::ulittle32_t*>(buf); + const char *offsets = buf + 4; + buf += 4 + (member_count * 4); // Skip offsets. + const char *indicies = buf + 4; + + uint16_t offsetindex = + *(reinterpret_cast<const support::ulittle16_t*>(indicies) + + SymbolIndex); + + uint32_t offset = *(reinterpret_cast<const support::ulittle32_t*>(offsets) + + (offsetindex - 1)); + + const char *Loc = Parent->getData().begin() + offset; + size_t Size = sizeof(ArchiveMemberHeader) + + ToHeader(Loc)->getSize(); + Result = Child(Parent, StringRef(Loc, Size)); + + return object_error::success; +} + +Archive::Symbol Archive::Symbol::getNext() const { + Symbol t(*this); + // Go to one past next null. + t.StringIndex = + Parent->SymbolTable->getBuffer()->getBuffer().find('\0', t.StringIndex) + 1; + ++t.SymbolIndex; + return t; +} + +Archive::symbol_iterator Archive::begin_symbols() const { + const char *buf = SymbolTable->getBuffer()->getBufferStart(); + uint32_t member_count = *reinterpret_cast<const support::ulittle32_t*>(buf); + buf += 4 + (member_count * 4); // Skip offsets. + uint32_t symbol_count = *reinterpret_cast<const support::ulittle32_t*>(buf); + buf += 4 + (symbol_count * 2); // Skip indices. + uint32_t string_start_offset = + buf - SymbolTable->getBuffer()->getBufferStart(); + return symbol_iterator(Symbol(this, 0, string_start_offset)); +} + +Archive::symbol_iterator Archive::end_symbols() const { + const char *buf = SymbolTable->getBuffer()->getBufferStart(); + uint32_t member_count = *reinterpret_cast<const support::ulittle32_t*>(buf); + buf += 4 + (member_count * 4); // Skip offsets. + uint32_t symbol_count = *reinterpret_cast<const support::ulittle32_t*>(buf); + return symbol_iterator( + Symbol(this, symbol_count, 0)); +} |
