platform_system_core/libunwindstack/tests/ElfTestUtils.cpp
Christopher Ferris d226a51409 Make the library usable as a library.
- Add namespace unwindstack everywhere so that it's easier for other
  code to use the library.
- Move some of the header files into include/unwindstack so that they
  can be exposed.
- Modify the headers so that only a limited number need to be exposed.
- Update the tools to use the new headers.
- Add a GetLoadBias() call on the Elf object. This prevents the need
  to get the interface object out of the Elf object.
- Move the GetRelPc() call out of the Reg class, to the Elf class. It's
  not always the case that a Reg object will be around when you want to
  get a relative pc. The tests for this moved to ElfTest.cpp.

Bug: 23762183

Test: Unit tests pass.
Change-Id: Iac609dac1dd90ed83d1a1e24ff2579c96c023bc3
2017-07-14 12:20:23 -07:00

142 lines
4.4 KiB
C++

/*
* Copyright (C) 2016 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <elf.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/ptrace.h>
#include <sys/types.h>
#include <unistd.h>
#include <string>
#include <vector>
#include <gtest/gtest.h>
#include "ElfTestUtils.h"
namespace unwindstack {
template <typename Ehdr>
void TestInitEhdr(Ehdr* ehdr, uint32_t elf_class, uint32_t machine_type) {
memset(ehdr, 0, sizeof(Ehdr));
memcpy(&ehdr->e_ident[0], ELFMAG, SELFMAG);
ehdr->e_ident[EI_DATA] = ELFDATA2LSB;
ehdr->e_ident[EI_VERSION] = EV_CURRENT;
ehdr->e_ident[EI_OSABI] = ELFOSABI_SYSV;
ehdr->e_ident[EI_CLASS] = elf_class;
ehdr->e_type = ET_DYN;
ehdr->e_machine = machine_type;
ehdr->e_version = EV_CURRENT;
ehdr->e_ehsize = sizeof(Ehdr);
}
static std::string GetTestFileDirectory() {
std::string exec(testing::internal::GetArgvs()[0]);
auto const value = exec.find_last_of('/');
if (value == std::string::npos) {
return "tests/files/";
}
return exec.substr(0, value + 1) + "tests/files/";
}
template <typename Ehdr, typename Shdr>
void TestInitGnuDebugdata(uint32_t elf_class, uint32_t machine, bool init_gnu_debugdata,
TestCopyFuncType copy_func) {
Ehdr ehdr;
TestInitEhdr(&ehdr, elf_class, machine);
uint64_t offset = sizeof(Ehdr);
ehdr.e_shoff = offset;
ehdr.e_shnum = 3;
ehdr.e_shentsize = sizeof(Shdr);
ehdr.e_shstrndx = 2;
copy_func(0, &ehdr, sizeof(ehdr));
Shdr shdr;
memset(&shdr, 0, sizeof(shdr));
shdr.sh_type = SHT_NULL;
copy_func(offset, &shdr, sizeof(shdr));
offset += ehdr.e_shentsize;
// Skip this header, it will contain the gnu_debugdata information.
uint64_t gnu_offset = offset;
offset += ehdr.e_shentsize;
uint64_t symtab_offset = sizeof(ehdr) + ehdr.e_shnum * ehdr.e_shentsize;
memset(&shdr, 0, sizeof(shdr));
shdr.sh_name = 1;
shdr.sh_type = SHT_STRTAB;
shdr.sh_offset = symtab_offset;
shdr.sh_size = 0x100;
copy_func(offset, &shdr, sizeof(shdr));
char value = '\0';
uint64_t symname_offset = symtab_offset;
copy_func(symname_offset, &value, 1);
symname_offset++;
std::string name(".shstrtab");
copy_func(symname_offset, name.c_str(), name.size() + 1);
symname_offset += name.size() + 1;
name = ".gnu_debugdata";
copy_func(symname_offset, name.c_str(), name.size() + 1);
ssize_t bytes = 0x100;
offset = symtab_offset + 0x100;
if (init_gnu_debugdata) {
// Read in the compressed elf data and copy it in.
name = GetTestFileDirectory();
if (elf_class == ELFCLASS32) {
name += "elf32.xz";
} else {
name += "elf64.xz";
}
int fd = TEMP_FAILURE_RETRY(open(name.c_str(), O_RDONLY));
ASSERT_NE(-1, fd) << "Cannot open " + name;
// Assumes the file is less than 1024 bytes.
std::vector<uint8_t> buf(1024);
bytes = TEMP_FAILURE_RETRY(read(fd, buf.data(), buf.size()));
ASSERT_GT(bytes, 0);
// Make sure the file isn't too big.
ASSERT_NE(static_cast<size_t>(bytes), buf.size())
<< "File " + name + " is too big, increase buffer size.";
close(fd);
buf.resize(bytes);
copy_func(offset, buf.data(), buf.size());
}
memset(&shdr, 0, sizeof(shdr));
shdr.sh_type = SHT_PROGBITS;
shdr.sh_name = symname_offset - symtab_offset;
shdr.sh_addr = offset;
shdr.sh_offset = offset;
shdr.sh_size = bytes;
copy_func(gnu_offset, &shdr, sizeof(shdr));
}
template void TestInitEhdr<Elf32_Ehdr>(Elf32_Ehdr*, uint32_t, uint32_t);
template void TestInitEhdr<Elf64_Ehdr>(Elf64_Ehdr*, uint32_t, uint32_t);
template void TestInitGnuDebugdata<Elf32_Ehdr, Elf32_Shdr>(uint32_t, uint32_t, bool,
TestCopyFuncType);
template void TestInitGnuDebugdata<Elf64_Ehdr, Elf64_Shdr>(uint32_t, uint32_t, bool,
TestCopyFuncType);
} // namespace unwindstack