| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <stdint.h> |
| #include <fcntl.h> |
| #include <sys/ioctl.h> |
| #include <errno.h> |
| #include <unistd.h> |
| |
| int cmp_main(int argc, char *argv[]) |
| { |
| int c; |
| int fd1, fd2; |
| char buf1[4096], buf2[4096]; |
| int res, res1, res2; |
| int rv = 0; |
| int i; |
| int filepos = 0; |
| |
| int show_byte = 0; |
| int show_all = 0; |
| int limit = 0; |
| |
| do { |
| c = getopt(argc, argv, "bln:"); |
| if (c == EOF) |
| break; |
| switch (c) { |
| case 'b': |
| show_byte = 1; |
| break; |
| case 'l': |
| show_all = 1; |
| break; |
| case 'n': |
| limit = atoi(optarg); |
| break; |
| case '?': |
| fprintf(stderr, "%s: invalid option -%c\n", |
| argv[0], optopt); |
| exit(1); |
| } |
| } while (1); |
| |
| if (optind + 2 != argc) { |
| fprintf(stderr, "Usage: %s [-b] [-l] [-n count] file1 file2\n", argv[0]); |
| exit(1); |
| } |
| |
| fd1 = open(argv[optind], O_RDONLY); |
| if(fd1 < 0) { |
| fprintf(stderr, "could not open %s, %s\n", argv[optind], strerror(errno)); |
| return 1; |
| } |
| |
| fd2 = open(argv[optind+1], O_RDONLY); |
| if(fd2 < 0) { |
| fprintf(stderr, "could not open %s, %s\n", argv[optind+1], strerror(errno)); |
| return 1; |
| } |
| |
| while(1) { |
| res1 = read(fd1, &buf1, sizeof(buf1)); |
| res2 = read(fd2, &buf2, sizeof(buf2)); |
| res = res1 < res2 ? res1 : res2; |
| if(res1 == 0 && res2 == 0) { |
| return rv; |
| } |
| for(i = 0; i < res; i++) { |
| if(buf1[i] != buf2[i]) { |
| printf("%s %s differ byte %d", argv[optind], argv[optind+1], filepos + i); |
| if(show_byte) |
| printf(" 0x%02x 0x%02x", buf1[i], buf2[i]); |
| printf("\n"); |
| if(!show_all) |
| return 1; |
| rv = 1; |
| } |
| if(limit) { |
| limit--; |
| if(limit == 0) |
| return rv; |
| } |
| } |
| if(res1 != res2 || res < 0) { |
| printf("%s on %s\n", res < 0 ? "Read error" : "EOF", res1 < res2 ? argv[optind] : argv[optind+1]); |
| return 1; |
| } |
| filepos += res; |
| } |
| } |