125b3c049e70834cf33790a28643ab058b507b35cBen Cheng/* Compute CRC32 checksum of file contents. 225b3c049e70834cf33790a28643ab058b507b35cBen Cheng Copyright (C) 2006 Red Hat, Inc. 303333823c75a1c1887e923828113a1b0fd12020cElliott Hughes This file is part of elfutils. 425b3c049e70834cf33790a28643ab058b507b35cBen Cheng 503333823c75a1c1887e923828113a1b0fd12020cElliott Hughes This file is free software; you can redistribute it and/or modify 603333823c75a1c1887e923828113a1b0fd12020cElliott Hughes it under the terms of either 725b3c049e70834cf33790a28643ab058b507b35cBen Cheng 803333823c75a1c1887e923828113a1b0fd12020cElliott Hughes * the GNU Lesser General Public License as published by the Free 903333823c75a1c1887e923828113a1b0fd12020cElliott Hughes Software Foundation; either version 3 of the License, or (at 1003333823c75a1c1887e923828113a1b0fd12020cElliott Hughes your option) any later version 1103333823c75a1c1887e923828113a1b0fd12020cElliott Hughes 1203333823c75a1c1887e923828113a1b0fd12020cElliott Hughes or 1303333823c75a1c1887e923828113a1b0fd12020cElliott Hughes 1403333823c75a1c1887e923828113a1b0fd12020cElliott Hughes * the GNU General Public License as published by the Free 1503333823c75a1c1887e923828113a1b0fd12020cElliott Hughes Software Foundation; either version 2 of the License, or (at 1603333823c75a1c1887e923828113a1b0fd12020cElliott Hughes your option) any later version 1703333823c75a1c1887e923828113a1b0fd12020cElliott Hughes 1803333823c75a1c1887e923828113a1b0fd12020cElliott Hughes or both in parallel, as here. 1903333823c75a1c1887e923828113a1b0fd12020cElliott Hughes 2003333823c75a1c1887e923828113a1b0fd12020cElliott Hughes elfutils is distributed in the hope that it will be useful, but 2125b3c049e70834cf33790a28643ab058b507b35cBen Cheng WITHOUT ANY WARRANTY; without even the implied warranty of 2225b3c049e70834cf33790a28643ab058b507b35cBen Cheng MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 2325b3c049e70834cf33790a28643ab058b507b35cBen Cheng General Public License for more details. 2425b3c049e70834cf33790a28643ab058b507b35cBen Cheng 2503333823c75a1c1887e923828113a1b0fd12020cElliott Hughes You should have received copies of the GNU General Public License and 2603333823c75a1c1887e923828113a1b0fd12020cElliott Hughes the GNU Lesser General Public License along with this program. If 2703333823c75a1c1887e923828113a1b0fd12020cElliott Hughes not, see <http://www.gnu.org/licenses/>. */ 2825b3c049e70834cf33790a28643ab058b507b35cBen Cheng 2903333823c75a1c1887e923828113a1b0fd12020cElliott Hughes#ifdef HAVE_CONFIG_H 3003333823c75a1c1887e923828113a1b0fd12020cElliott Hughes# include <config.h> 3103333823c75a1c1887e923828113a1b0fd12020cElliott Hughes#endif 3225b3c049e70834cf33790a28643ab058b507b35cBen Cheng 3325b3c049e70834cf33790a28643ab058b507b35cBen Cheng#include "system.h" 3425b3c049e70834cf33790a28643ab058b507b35cBen Cheng#include <errno.h> 3525b3c049e70834cf33790a28643ab058b507b35cBen Cheng#include <unistd.h> 3625b3c049e70834cf33790a28643ab058b507b35cBen Cheng#include <sys/stat.h> 3725b3c049e70834cf33790a28643ab058b507b35cBen Cheng#include <sys/mman.h> 3825b3c049e70834cf33790a28643ab058b507b35cBen Cheng 3925b3c049e70834cf33790a28643ab058b507b35cBen Chengint 4025b3c049e70834cf33790a28643ab058b507b35cBen Chengcrc32_file (int fd, uint32_t *resp) 4125b3c049e70834cf33790a28643ab058b507b35cBen Cheng{ 4225b3c049e70834cf33790a28643ab058b507b35cBen Cheng unsigned char buffer[1024 * 8]; 4325b3c049e70834cf33790a28643ab058b507b35cBen Cheng uint32_t crc = 0; 4425b3c049e70834cf33790a28643ab058b507b35cBen Cheng off_t off = 0; 4525b3c049e70834cf33790a28643ab058b507b35cBen Cheng ssize_t count; 4625b3c049e70834cf33790a28643ab058b507b35cBen Cheng 4725b3c049e70834cf33790a28643ab058b507b35cBen Cheng struct stat st; 4825b3c049e70834cf33790a28643ab058b507b35cBen Cheng if (fstat (fd, &st) == 0) 4925b3c049e70834cf33790a28643ab058b507b35cBen Cheng { 5025b3c049e70834cf33790a28643ab058b507b35cBen Cheng /* Try mapping in the file data. */ 5125b3c049e70834cf33790a28643ab058b507b35cBen Cheng size_t mapsize = st.st_size; 5225b3c049e70834cf33790a28643ab058b507b35cBen Cheng void *mapped = mmap (NULL, mapsize, PROT_READ, MAP_PRIVATE, fd, 0); 5325b3c049e70834cf33790a28643ab058b507b35cBen Cheng if (mapped == MAP_FAILED && errno == ENOMEM) 5425b3c049e70834cf33790a28643ab058b507b35cBen Cheng { 5525b3c049e70834cf33790a28643ab058b507b35cBen Cheng const size_t pagesize = sysconf (_SC_PAGE_SIZE); 5625b3c049e70834cf33790a28643ab058b507b35cBen Cheng mapsize = ((mapsize / 2) + pagesize - 1) & -pagesize; 5725b3c049e70834cf33790a28643ab058b507b35cBen Cheng while (mapsize >= pagesize 5825b3c049e70834cf33790a28643ab058b507b35cBen Cheng && (mapped = mmap (NULL, mapsize, PROT_READ, MAP_PRIVATE, 5925b3c049e70834cf33790a28643ab058b507b35cBen Cheng fd, 0)) == MAP_FAILED && errno == ENOMEM) 6025b3c049e70834cf33790a28643ab058b507b35cBen Cheng mapsize /= 2; 6125b3c049e70834cf33790a28643ab058b507b35cBen Cheng } 6225b3c049e70834cf33790a28643ab058b507b35cBen Cheng if (mapped != MAP_FAILED) 6325b3c049e70834cf33790a28643ab058b507b35cBen Cheng { 6425b3c049e70834cf33790a28643ab058b507b35cBen Cheng do 6525b3c049e70834cf33790a28643ab058b507b35cBen Cheng { 6625b3c049e70834cf33790a28643ab058b507b35cBen Cheng if (st.st_size <= (off_t) mapsize) 6725b3c049e70834cf33790a28643ab058b507b35cBen Cheng { 6825b3c049e70834cf33790a28643ab058b507b35cBen Cheng *resp = crc32 (crc, mapped, st.st_size); 6925b3c049e70834cf33790a28643ab058b507b35cBen Cheng munmap (mapped, mapsize); 7025b3c049e70834cf33790a28643ab058b507b35cBen Cheng return 0; 7125b3c049e70834cf33790a28643ab058b507b35cBen Cheng } 7225b3c049e70834cf33790a28643ab058b507b35cBen Cheng crc = crc32 (crc, mapped, mapsize); 7325b3c049e70834cf33790a28643ab058b507b35cBen Cheng off += mapsize; 7425b3c049e70834cf33790a28643ab058b507b35cBen Cheng st.st_size -= mapsize; 7525b3c049e70834cf33790a28643ab058b507b35cBen Cheng } while (mmap (mapped, mapsize, PROT_READ, MAP_FIXED|MAP_PRIVATE, 7625b3c049e70834cf33790a28643ab058b507b35cBen Cheng fd, off) == mapped); 7725b3c049e70834cf33790a28643ab058b507b35cBen Cheng munmap (mapped, mapsize); 7825b3c049e70834cf33790a28643ab058b507b35cBen Cheng } 7925b3c049e70834cf33790a28643ab058b507b35cBen Cheng } 8025b3c049e70834cf33790a28643ab058b507b35cBen Cheng 8125b3c049e70834cf33790a28643ab058b507b35cBen Cheng while ((count = TEMP_FAILURE_RETRY (pread (fd, buffer, sizeof buffer, 8225b3c049e70834cf33790a28643ab058b507b35cBen Cheng off))) > 0) 8325b3c049e70834cf33790a28643ab058b507b35cBen Cheng { 8425b3c049e70834cf33790a28643ab058b507b35cBen Cheng off += count; 8525b3c049e70834cf33790a28643ab058b507b35cBen Cheng crc = crc32 (crc, buffer, count); 8625b3c049e70834cf33790a28643ab058b507b35cBen Cheng } 8725b3c049e70834cf33790a28643ab058b507b35cBen Cheng 8825b3c049e70834cf33790a28643ab058b507b35cBen Cheng *resp = crc; 8925b3c049e70834cf33790a28643ab058b507b35cBen Cheng 9025b3c049e70834cf33790a28643ab058b507b35cBen Cheng return count == 0 ? 0 : -1; 9125b3c049e70834cf33790a28643ab058b507b35cBen Cheng} 92