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/*
* 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 <stdint.h>
#include <stdio.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <string>
#if !defined(EM_AARCH64)
#define EM_AARCH64 183
#endif
template <typename Ehdr>
void InitEhdr(Ehdr* ehdr, uint32_t elf_class, uint32_t machine) {
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;
ehdr->e_version = EV_CURRENT;
ehdr->e_ehsize = sizeof(Ehdr);
}
template <typename Ehdr, typename Shdr>
void GenElf(Ehdr* ehdr, int fd) {
uint64_t offset = sizeof(Ehdr);
ehdr->e_shoff = offset;
ehdr->e_shnum = 3;
ehdr->e_shentsize = sizeof(Shdr);
ehdr->e_shstrndx = 2;
TEMP_FAILURE_RETRY(write(fd, ehdr, sizeof(Ehdr)));
Shdr shdr;
memset(&shdr, 0, sizeof(shdr));
shdr.sh_name = 0;
shdr.sh_type = SHT_NULL;
TEMP_FAILURE_RETRY(write(fd, &shdr, sizeof(Shdr)));
offset += ehdr->e_shentsize;
memset(&shdr, 0, sizeof(shdr));
shdr.sh_type = SHT_PROGBITS;
shdr.sh_name = 11;
shdr.sh_addr = 0x5000;
shdr.sh_offset = 0x5000;
shdr.sh_entsize = 0x100;
shdr.sh_size = 0x800;
TEMP_FAILURE_RETRY(write(fd, &shdr, sizeof(Shdr)));
offset += ehdr->e_shentsize;
memset(&shdr, 0, sizeof(shdr));
shdr.sh_type = SHT_STRTAB;
shdr.sh_name = 1;
shdr.sh_offset = 0x200;
shdr.sh_size = 24;
TEMP_FAILURE_RETRY(write(fd, &shdr, sizeof(Shdr)));
// Write out the name entries information.
lseek(fd, 0x200, SEEK_SET);
std::string name;
TEMP_FAILURE_RETRY(write(fd, name.data(), name.size() + 1));
name = ".shstrtab";
TEMP_FAILURE_RETRY(write(fd, name.data(), name.size() + 1));
name = ".debug_frame";
TEMP_FAILURE_RETRY(write(fd, name.data(), name.size() + 1));
}
int main() {
int elf32_fd = TEMP_FAILURE_RETRY(open("elf32", O_RDWR | O_CREAT | O_TRUNC | O_CLOEXEC, 0644));
if (elf32_fd == -1) {
printf("Failed to create elf32: %s\n", strerror(errno));
return 1;
}
int elf64_fd = TEMP_FAILURE_RETRY(open("elf64", O_RDWR | O_CREAT | O_TRUNC | O_CLOEXEC, 0644));
if (elf64_fd == -1) {
printf("Failed to create elf64: %s\n", strerror(errno));
return 1;
}
Elf32_Ehdr ehdr32;
InitEhdr<Elf32_Ehdr>(&ehdr32, ELFCLASS32, EM_ARM);
GenElf<Elf32_Ehdr, Elf32_Shdr>(&ehdr32, elf32_fd);
close(elf32_fd);
Elf64_Ehdr ehdr64;
InitEhdr<Elf64_Ehdr>(&ehdr64, ELFCLASS64, EM_AARCH64);
GenElf<Elf64_Ehdr, Elf64_Shdr>(&ehdr64, elf64_fd);
close(elf64_fd);
}
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