object_file.cc revision 11391
1/* 2 * Copyright (c) 2002-2004 The Regents of The University of Michigan 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are 7 * met: redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer; 9 * redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution; 12 * neither the name of the copyright holders nor the names of its 13 * contributors may be used to endorse or promote products derived from 14 * this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 * 28 * Authors: Nathan Binkert 29 * Steve Reinhardt 30 */ 31 32#include <sys/mman.h> 33#include <sys/types.h> 34#include <fcntl.h> 35#include <unistd.h> 36#include <zlib.h> 37 38#include <cstdio> 39#include <list> 40#include <string> 41 42#include "base/loader/aout_object.hh" 43#include "base/loader/dtb_object.hh" 44#include "base/loader/ecoff_object.hh" 45#include "base/loader/elf_object.hh" 46#include "base/loader/object_file.hh" 47#include "base/loader/raw_object.hh" 48#include "base/loader/symtab.hh" 49#include "base/cprintf.hh" 50#include "mem/port_proxy.hh" 51 52using namespace std; 53 54ObjectFile::ObjectFile(const string &_filename, 55 size_t _len, uint8_t *_data, 56 Arch _arch, OpSys _op_sys) 57 : filename(_filename), fileData(_data), len(_len), 58 arch(_arch), opSys(_op_sys), entry(0), globalPtr(0), 59 text{0, nullptr, 0}, data{0, nullptr, 0}, bss{0, nullptr, 0} 60{ 61} 62 63 64ObjectFile::~ObjectFile() 65{ 66 if (fileData) { 67 ::munmap((char*)fileData, len); 68 fileData = NULL; 69 } 70} 71 72 73bool 74ObjectFile::loadSection(Section *sec, PortProxy& mem_proxy, Addr addr_mask, 75 Addr offset) 76{ 77 if (sec->size != 0) { 78 Addr addr = (sec->baseAddr & addr_mask) + offset; 79 if (sec->fileImage) { 80 mem_proxy.writeBlob(addr, sec->fileImage, sec->size); 81 } 82 else { 83 // no image: must be bss 84 mem_proxy.memsetBlob(addr, 0, sec->size); 85 } 86 } 87 return true; 88} 89 90 91bool 92ObjectFile::loadSections(PortProxy& mem_proxy, Addr addr_mask, Addr offset) 93{ 94 return (loadSection(&text, mem_proxy, addr_mask, offset) 95 && loadSection(&data, mem_proxy, addr_mask, offset) 96 && loadSection(&bss, mem_proxy, addr_mask, offset)); 97} 98 99static bool 100hasGzipMagic(int fd) 101{ 102 uint8_t buf[2] = {0}; 103 size_t sz = pread(fd, buf, 2, 0); 104 panic_if(sz != 2, "Couldn't read magic bytes from object file"); 105 return ((buf[0] == 0x1f) && (buf[1] == 0x8b)); 106} 107 108static int 109doGzipLoad(int fd) 110{ 111 const size_t blk_sz = 4096; 112 113 gzFile fdz = gzdopen(fd, "rb"); 114 if (!fdz) { 115 return -1; 116 } 117 118 size_t tmp_len = strlen(P_tmpdir); 119 char *tmpnam = (char*) malloc(tmp_len + 20); 120 strcpy(tmpnam, P_tmpdir); 121 strcpy(tmpnam+tmp_len, "/gem5-gz-obj-XXXXXX"); // 19 chars 122 fd = mkstemp(tmpnam); // repurposing fd variable for output 123 if (fd < 0) { 124 free(tmpnam); 125 gzclose(fdz); 126 return fd; 127 } 128 129 if (unlink(tmpnam) != 0) 130 warn("couldn't remove temporary file %s\n", tmpnam); 131 132 free(tmpnam); 133 134 auto buf = new uint8_t[blk_sz]; 135 int r; // size of (r)emaining uncopied data in (buf)fer 136 while ((r = gzread(fdz, buf, blk_sz)) > 0) { 137 auto p = buf; // pointer into buffer 138 while (r > 0) { 139 auto sz = write(fd, p, r); 140 assert(sz <= r); 141 r -= sz; 142 p += sz; 143 } 144 } 145 delete[] buf; 146 gzclose(fdz); 147 if (r < 0) { // error 148 close(fd); 149 return -1; 150 } 151 assert(r == 0); // finished successfully 152 return fd; // return fd to decompressed temporary file for mmap()'ing 153} 154 155ObjectFile * 156createObjectFile(const string &fname, bool raw) 157{ 158 // open the file 159 int fd = open(fname.c_str(), O_RDONLY); 160 if (fd < 0) { 161 return NULL; 162 } 163 164 // decompress GZ files 165 if (hasGzipMagic(fd)) { 166 fd = doGzipLoad(fd); 167 if (fd < 0) { 168 return NULL; 169 } 170 } 171 172 // find the length of the file by seeking to the end 173 off_t off = lseek(fd, 0, SEEK_END); 174 fatal_if(off < 0, 175 "Failed to determine size of object file %s\n", fname); 176 auto len = static_cast<size_t>(off); 177 178 // mmap the whole shebang 179 uint8_t *file_data = (uint8_t *)mmap(NULL, len, PROT_READ, MAP_SHARED, 180 fd, 0); 181 close(fd); 182 183 if (file_data == MAP_FAILED) { 184 return NULL; 185 } 186 187 ObjectFile *file_obj = NULL; 188 189 // figure out what we have here 190 if ((file_obj = ElfObject::tryFile(fname, len, file_data)) != NULL) { 191 return file_obj; 192 } 193 194 if ((file_obj = EcoffObject::tryFile(fname, len, file_data)) != NULL) { 195 return file_obj; 196 } 197 198 if ((file_obj = AoutObject::tryFile(fname, len, file_data)) != NULL) { 199 return file_obj; 200 } 201 202 if ((file_obj = DtbObject::tryFile(fname, len, file_data)) != NULL) { 203 return file_obj; 204 } 205 206 if (raw) 207 return RawObject::tryFile(fname, len, file_data); 208 209 // don't know what it is 210 munmap((char*)file_data, len); 211 return NULL; 212} 213