fastdfs/client/fdfs_crc32.c

106 lines
2.0 KiB
C

/**
* Copyright (C) 2008 Happy Fish / YuQing
*
* FastDFS may be copied only under the terms of the GNU General
* Public License V3, which may be found in the FastDFS source kit.
* Please visit the FastDFS Home Page http://www.fastken.com/ for more detail.
**/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include "fastcommon/hash.h"
int main(int argc, char *argv[])
{
int64_t file_size;
int64_t remain_bytes;
char *filename;
int fd;
int read_bytes;
int result;
int64_t crc32;
char buff[512 * 1024];
if (argc < 2)
{
printf("Usage: %s <filename>\n", argv[0]);
return 1;
}
filename = argv[1];
fd = open(filename, O_RDONLY);
if (fd < 0)
{
printf("file: "__FILE__", line: %d, " \
"open file %s fail, " \
"errno: %d, error info: %s\n", \
__LINE__, filename, errno, STRERROR(errno));
return errno != 0 ? errno : EACCES;
}
if ((file_size=lseek(fd, 0, SEEK_END)) < 0)
{
printf("file: "__FILE__", line: %d, " \
"call lseek fail, " \
"errno: %d, error info: %s\n", \
__LINE__, errno, STRERROR(errno));
close(fd);
return errno;
}
if (lseek(fd, 0, SEEK_SET) < 0)
{
printf("file: "__FILE__", line: %d, " \
"call lseek fail, " \
"errno: %d, error info: %s\n", \
__LINE__, errno, STRERROR(errno));
close(fd);
return errno;
}
crc32 = CRC32_XINIT;
result = 0;
remain_bytes = file_size;
while (remain_bytes > 0)
{
if (remain_bytes > sizeof(buff))
{
read_bytes = sizeof(buff);
}
else
{
read_bytes = remain_bytes;
}
if (read(fd, buff, read_bytes) != read_bytes)
{
printf("file: "__FILE__", line: %d, " \
"call lseek fail, " \
"errno: %d, error info: %s\n", \
__LINE__, errno, STRERROR(errno));
result = errno != 0 ? errno : EIO;
break;
}
crc32 = CRC32_ex(buff, read_bytes, crc32);
remain_bytes -= read_bytes;
}
close(fd);
if (result == 0)
{
crc32 = CRC32_FINAL(crc32);
printf("%x\n", (int)crc32);
}
return result;
}