llvm/lib/Object/Object.cpp
Kevin Enderby c6bf9be16d Thread Expected<...> up from createMachOObjectFile() to allow llvm-objdump to produce a real error message
Produce the first specific error message for a malformed Mach-O file describing
the problem instead of the generic message for object_error::parse_failed of
"Invalid data was encountered while parsing the file”.  Many more good error
messages will follow after this first one.

This is built on Lang Hames’ great work of adding the ’Error' class for
structured error handling and threading Error through MachOObjectFile
construction.  And making createMachOObjectFile return Expected<...> .

So to to get the error to the llvm-obdump tool, I changed the stack of
these methods to also return Expected<...> :

  object::ObjectFile::createObjectFile()
  object::SymbolicFile::createSymbolicFile()
  object::createBinary()

Then finally in ParseInputMachO() in MachODump.cpp the error can
be reported and the specific error message can be printed in llvm-objdump
and can be seen in the existing test case for the existing malformed binary
but with the updated error message.

Converting these interfaces to Expected<> from ErrorOr<> does involve
touching a number of places. To contain the changes for now use of
errorToErrorCode() and errorOrToExpected() are used where the callers
are yet to be converted.

Also there some were bugs in the existing code that did not deal with the
old ErrorOr<> return values.  So now with Expected<> since they must be
checked and the error handled, I added a TODO and a comment:
“// TODO: Actually report errors helpfully” and a call something like
consumeError(ObjOrErr.takeError()) so the buggy code will not crash
since needed to deal with the Error.

Note there is one fix also needed to lld/COFF/InputFiles.cpp that goes along
with this that I will commit right after this.  So expect lld not to built
after this commit and before the next one.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@265606 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-06 22:14:09 +00:00

226 lines
6.7 KiB
C++

//===- Object.cpp - C bindings to the object file library--------*- 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 C bindings to the file-format-independent object
// library.
//
//===----------------------------------------------------------------------===//
#include "llvm/ADT/SmallVector.h"
#include "llvm-c/Object.h"
#include "llvm/Object/ObjectFile.h"
using namespace llvm;
using namespace object;
inline OwningBinary<ObjectFile> *unwrap(LLVMObjectFileRef OF) {
return reinterpret_cast<OwningBinary<ObjectFile> *>(OF);
}
inline LLVMObjectFileRef wrap(const OwningBinary<ObjectFile> *OF) {
return reinterpret_cast<LLVMObjectFileRef>(
const_cast<OwningBinary<ObjectFile> *>(OF));
}
inline section_iterator *unwrap(LLVMSectionIteratorRef SI) {
return reinterpret_cast<section_iterator*>(SI);
}
inline LLVMSectionIteratorRef
wrap(const section_iterator *SI) {
return reinterpret_cast<LLVMSectionIteratorRef>
(const_cast<section_iterator*>(SI));
}
inline symbol_iterator *unwrap(LLVMSymbolIteratorRef SI) {
return reinterpret_cast<symbol_iterator*>(SI);
}
inline LLVMSymbolIteratorRef
wrap(const symbol_iterator *SI) {
return reinterpret_cast<LLVMSymbolIteratorRef>
(const_cast<symbol_iterator*>(SI));
}
inline relocation_iterator *unwrap(LLVMRelocationIteratorRef SI) {
return reinterpret_cast<relocation_iterator*>(SI);
}
inline LLVMRelocationIteratorRef
wrap(const relocation_iterator *SI) {
return reinterpret_cast<LLVMRelocationIteratorRef>
(const_cast<relocation_iterator*>(SI));
}
// ObjectFile creation
LLVMObjectFileRef LLVMCreateObjectFile(LLVMMemoryBufferRef MemBuf) {
std::unique_ptr<MemoryBuffer> Buf(unwrap(MemBuf));
Expected<std::unique_ptr<ObjectFile>> ObjOrErr(
ObjectFile::createObjectFile(Buf->getMemBufferRef()));
std::unique_ptr<ObjectFile> Obj;
if (!ObjOrErr) {
// TODO: Actually report errors helpfully.
consumeError(ObjOrErr.takeError());
return nullptr;
}
auto *Ret = new OwningBinary<ObjectFile>(std::move(ObjOrErr.get()), std::move(Buf));
return wrap(Ret);
}
void LLVMDisposeObjectFile(LLVMObjectFileRef ObjectFile) {
delete unwrap(ObjectFile);
}
// ObjectFile Section iterators
LLVMSectionIteratorRef LLVMGetSections(LLVMObjectFileRef OF) {
OwningBinary<ObjectFile> *OB = unwrap(OF);
section_iterator SI = OB->getBinary()->section_begin();
return wrap(new section_iterator(SI));
}
void LLVMDisposeSectionIterator(LLVMSectionIteratorRef SI) {
delete unwrap(SI);
}
LLVMBool LLVMIsSectionIteratorAtEnd(LLVMObjectFileRef OF,
LLVMSectionIteratorRef SI) {
OwningBinary<ObjectFile> *OB = unwrap(OF);
return (*unwrap(SI) == OB->getBinary()->section_end()) ? 1 : 0;
}
void LLVMMoveToNextSection(LLVMSectionIteratorRef SI) {
++(*unwrap(SI));
}
void LLVMMoveToContainingSection(LLVMSectionIteratorRef Sect,
LLVMSymbolIteratorRef Sym) {
ErrorOr<section_iterator> SecOrErr = (*unwrap(Sym))->getSection();
if (std::error_code ec = SecOrErr.getError())
report_fatal_error(ec.message());
*unwrap(Sect) = *SecOrErr;
}
// ObjectFile Symbol iterators
LLVMSymbolIteratorRef LLVMGetSymbols(LLVMObjectFileRef OF) {
OwningBinary<ObjectFile> *OB = unwrap(OF);
symbol_iterator SI = OB->getBinary()->symbol_begin();
return wrap(new symbol_iterator(SI));
}
void LLVMDisposeSymbolIterator(LLVMSymbolIteratorRef SI) {
delete unwrap(SI);
}
LLVMBool LLVMIsSymbolIteratorAtEnd(LLVMObjectFileRef OF,
LLVMSymbolIteratorRef SI) {
OwningBinary<ObjectFile> *OB = unwrap(OF);
return (*unwrap(SI) == OB->getBinary()->symbol_end()) ? 1 : 0;
}
void LLVMMoveToNextSymbol(LLVMSymbolIteratorRef SI) {
++(*unwrap(SI));
}
// SectionRef accessors
const char *LLVMGetSectionName(LLVMSectionIteratorRef SI) {
StringRef ret;
if (std::error_code ec = (*unwrap(SI))->getName(ret))
report_fatal_error(ec.message());
return ret.data();
}
uint64_t LLVMGetSectionSize(LLVMSectionIteratorRef SI) {
return (*unwrap(SI))->getSize();
}
const char *LLVMGetSectionContents(LLVMSectionIteratorRef SI) {
StringRef ret;
if (std::error_code ec = (*unwrap(SI))->getContents(ret))
report_fatal_error(ec.message());
return ret.data();
}
uint64_t LLVMGetSectionAddress(LLVMSectionIteratorRef SI) {
return (*unwrap(SI))->getAddress();
}
LLVMBool LLVMGetSectionContainsSymbol(LLVMSectionIteratorRef SI,
LLVMSymbolIteratorRef Sym) {
return (*unwrap(SI))->containsSymbol(**unwrap(Sym));
}
// Section Relocation iterators
LLVMRelocationIteratorRef LLVMGetRelocations(LLVMSectionIteratorRef Section) {
relocation_iterator SI = (*unwrap(Section))->relocation_begin();
return wrap(new relocation_iterator(SI));
}
void LLVMDisposeRelocationIterator(LLVMRelocationIteratorRef SI) {
delete unwrap(SI);
}
LLVMBool LLVMIsRelocationIteratorAtEnd(LLVMSectionIteratorRef Section,
LLVMRelocationIteratorRef SI) {
return (*unwrap(SI) == (*unwrap(Section))->relocation_end()) ? 1 : 0;
}
void LLVMMoveToNextRelocation(LLVMRelocationIteratorRef SI) {
++(*unwrap(SI));
}
// SymbolRef accessors
const char *LLVMGetSymbolName(LLVMSymbolIteratorRef SI) {
ErrorOr<StringRef> Ret = (*unwrap(SI))->getName();
if (std::error_code EC = Ret.getError())
report_fatal_error(EC.message());
return Ret->data();
}
uint64_t LLVMGetSymbolAddress(LLVMSymbolIteratorRef SI) {
ErrorOr<uint64_t> Ret = (*unwrap(SI))->getAddress();
if (std::error_code EC = Ret.getError())
report_fatal_error(EC.message());
return *Ret;
}
uint64_t LLVMGetSymbolSize(LLVMSymbolIteratorRef SI) {
return (*unwrap(SI))->getCommonSize();
}
// RelocationRef accessors
uint64_t LLVMGetRelocationOffset(LLVMRelocationIteratorRef RI) {
return (*unwrap(RI))->getOffset();
}
LLVMSymbolIteratorRef LLVMGetRelocationSymbol(LLVMRelocationIteratorRef RI) {
symbol_iterator ret = (*unwrap(RI))->getSymbol();
return wrap(new symbol_iterator(ret));
}
uint64_t LLVMGetRelocationType(LLVMRelocationIteratorRef RI) {
return (*unwrap(RI))->getType();
}
// NOTE: Caller takes ownership of returned string.
const char *LLVMGetRelocationTypeName(LLVMRelocationIteratorRef RI) {
SmallVector<char, 0> ret;
(*unwrap(RI))->getTypeName(ret);
char *str = static_cast<char*>(malloc(ret.size()));
std::copy(ret.begin(), ret.end(), str);
return str;
}
// NOTE: Caller takes ownership of returned string.
const char *LLVMGetRelocationValueString(LLVMRelocationIteratorRef RI) {
return strdup("");
}