collapseos/tools/blkunpack.c

65 lines
1.6 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/stat.h>
void usage()
{
fprintf(stderr, "Usage: blkunpack dirname\n");
}
int main(int argc, char *argv[])
{
char buf[1024];
int blkid = 0;
if (argc != 2) {
usage();
return 1;
}
while (fread(buf, 1024, 1, stdin) == 1) {
char fullpath[0x200];
sprintf(fullpath, "%s/%03d", argv[1], blkid);
int linecnt = 0 ;
for (int i=1023; i>=0; i--) {
if (buf[i]) {
linecnt = (i / 64) + 1;
break;
}
}
if (linecnt) {
// not an empty block
FILE *fp = fopen(fullpath, "w");
for (int i=0; i<linecnt; i++) {
char *line = &buf[i*64];
// line length is *not* strlen()! it's the
// position of the first non-null, starting
// from the right. Then, we normalize nulls
// to space.
int j;
for (j=63; j>=0; j--) {
if (line[j] != '\0') {
break;
}
}
int len = j+1;
if (len) {
for (; j>=0; j--) {
if (line[j] == '\0') {
line[j] = ' ';
}
}
fwrite(line, len, 1, fp);
}
fputc('\n', fp);
}
fclose(fp);
} else {
// empty block, delete
unlink(fullpath);
}
blkid++;
}
return 0;
}