1 /* 2 * Program for testing file locking. The original data file consists of 3 * characters from 'A' to 'Z'. The data file after running this program 4 * would consist of lines with 1's in even lines and 0's in odd lines. 5 */ 6 7 #include "nfs_flock.h" 8 #include <errno.h> 9 #include <stdio.h> 10 #include <stdlib.h> 11 #include <unistd.h> 12 13 #define BYTES 64 14 #define LINES 16384 15 16 int main(int argc, char **argv) 17 { 18 int i, fd, mac; 19 int offset = 0; 20 char buf[BUFSIZ]; 21 22 if (argc != 3) { 23 fprintf(stderr, "Usage: %s <mac num> <file name>\n", argv[0]); 24 exit(2); 25 } 26 27 if ((fd = open(argv[2], O_RDWR)) < 0) { 28 perror("opening a file"); 29 exit(1); 30 } 31 32 mac = atoi(argv[1]); 33 34 /* 35 * Replace a line of characters by 1's if it is process one 36 * else with 0's. Number of charcters in any line are BYTES-1, 37 * the last character being a newline character. 38 */ 39 for (i = 0; i < BYTES - 1; i++) { 40 if (mac == 1) 41 buf[i] = '1'; 42 else 43 buf[i] = '0'; 44 } 45 buf[BYTES - 1] = '\n'; 46 47 for (i = 0; i < LINES; i++) { 48 if (mac == 1) { /* Set the offset to even lines */ 49 if ((i % 2) == 0) { 50 if (i == 0) 51 offset = 0; 52 else 53 offset += 2 * BYTES; 54 } else 55 continue; 56 } else { /* Set the offset to odd lines */ 57 if ((i % 2) == 1) { 58 if (i == 1) 59 offset = BYTES; 60 else 61 offset += 2 * BYTES; 62 } else 63 continue; 64 } 65 66 if (writeb_lock(fd, offset, SEEK_SET, BYTES) < 0) 67 printf("failed in writeb_lock, Errno = %d", errno); 68 69 lseek(fd, offset, SEEK_SET); 70 71 /* write to the test file */ 72 write(fd, buf, BYTES); 73 74 if (unb_lock(fd, offset, SEEK_SET, BYTES) < 0) 75 printf("failed in unb_lock, Errno = %d", errno); 76 } 77 exit(0); 78 } 79
