FileCDC/utils.c at master · baixiangcpp/FileCDC · GitHub

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#include<fcntl.h>
#include<unistd.h>
#include<stdio.h>
#include<sys/types.h>
#include<errno.h>
#include<glib.h>
#include<glib/gstdio.h>
#include"utils.h"

ssize_treadn(intfd, void*vptr, size_tn)
{
size_tnleft;
ssize_tnread;
char*ptr;

ptr=vptr;
nleft=n;
while (nleft>0) {
if ( (nread=read(fd, ptr, nleft)) <0) {
if (errno==EINTR)
nread=0; /* and call read() again */
else
return(-1);
 } elseif (nread==0)
break; /* EOF */

nleft-=nread;
ptr+=nread;
	}
return(n-nleft); /* return >= 0 */
}

voidrawdata_to_hex (constunsigned char*rawdata, char*hex_str, intn_bytes)
{
staticconstcharhex[] ="0123456789abcdef";
inti;

for (i=0; i<n_bytes; i++) {
unsigned intval=*rawdata++;
*hex_str++=hex[val >> 4];
*hex_str++=hex[val&0xf];
 }
*hex_str='\0';
}

intdo_write_chunk (constunsigned char*checksum, constchar*buf, intlen)
{
charchksum_str[41];
intfd;
intn;

rawdata_to_hex (checksum, chksum_str, 20);

/* Don't write if the block already exists. */
if (g_access (chksum_str, F_OK) ==0)
return0;

fd=open (chksum_str, O_WRONLY|O_CREAT,0666);
if (fd==-1) {
printf ("Failed to open block %s.\n", chksum_str);
return-1;
 }

n=write (fd, buf, len);
if (n<0) {
printf ("Failed to write chunk %s.\n", chksum_str);
close (fd);
return-1;
 }

close(fd);

return0;
}