static ssize_t read_sectors(secaddr pos, void *buf, secaddr want)
{
- ssize_t n;
+ ssize_t n, done;
size_t lo, mid, hi;
+ int fakeerr = 0;
struct badblock *bad, *best;
+ unsigned char *p = buf;
best = 0; lo = 0; hi = badblocks.n;
#ifdef DEBUG
printf(";; next is %"PRIuSEC" .. %"PRIuSEC"\n",
best->start, best->end);
#endif
- if (best && pos + want > best->start) want = best->start - pos;
-
-again:
- if (vob)
- n = DVDReadBlocks(vob, pos - file->start, want, buf);
- else if (file) {
- if (lseek(dvdfd, (off_t)pos*SECTORSZ, SEEK_SET) < 0)
- bail_syserr(errno, "failed to seek to sector %"PRIuSEC"", pos);
- n = read(dvdfd, buf, want*SECTORSZ);
- if (n >= 0) n /= SECTORSZ;
- } else {
- memset(buf, 0, want*SECTORSZ);
- n = want;
+ if (best && pos + want > best->start)
+ { want = best->start - pos; fakeerr = EIO; }
+
+ done = 0;
+ while (want) {
+ if (vob)
+ { errno = 0; n = DVDReadBlocks(vob, pos - file->start, want, p); }
+ else if (file) {
+ if (lseek(dvdfd, (off_t)pos*SECTORSZ, SEEK_SET) < 0)
+ bail_syserr(errno, "failed to seek to sector %"PRIuSEC"", pos);
+ errno = 0; n = read(dvdfd, p, want*SECTORSZ);
+ if (n >= 0) n /= SECTORSZ;
+ } else {
+ memset(p, 0, want*SECTORSZ);
+ n = want;
+ }
+
+ if (n > 0) { done += n; pos += n; p += n*SECTORSZ; want -= n; }
+ else if (!n || errno != EINTR) break;
+ }
+ if (fakeerr && !errno) errno = fakeerr;
+ return (!done && errno ? -1 : done);
+}
+
+static ssize_t find_good_sector(secaddr *pos_inout, secaddr end,
+ unsigned char *buf, secaddr sz)
+{
+ int i;
+ secaddr pos = *pos_inout, bad_lo, bad_hi, good, step;
+ ssize_t n;
+
+ report_bad_blocks_progress(pos, pos, errno);
+ for (i = 0; i < 4; i++) {
+ n = read_sectors(pos, buf, 1);
+ if (n > 0) {
+ clear_progress();
+ moan("sector %"PRIuSEC" read ok after retry", pos);
+ bad_lo = bad_hi = pos;
+ goto recovered;
+ }
+ }
+
+ bad_lo = pos; step = 1; bad_hi = pos + 1;
+ for (;;) {
+ report_bad_blocks_progress(bad_lo, bad_hi, errno);
+ if (bad_hi >= end) {
+ clear_progress();
+ moan("giving up on this extent");
+ n = 0; goto recovered;
+ }
+ step *= 2;
+ if (step > end - bad_lo) step = end - bad_lo;
+ pos = bad_lo + step - 1;
+ n = read_sectors(pos, buf, 1);
+ if (n > 0) break;
+ bad_hi = pos + 1;
}
- if (n < 0 && errno == EINTR) goto again;
+ good = pos;
+ while (good > bad_hi) {
+ report_bad_blocks_progress(bad_lo, bad_hi, errno);
+ pos = bad_hi + (good - bad_hi)/2;
+ n = read_sectors(pos, buf, 1);
+ if (n > 0) good = pos;
+ else bad_hi = pos + 1;
+ }
+recovered:
+ if (bad_hi > bad_lo) {
+ clear_progress();
+ moan("skipping %"PRIuSEC" bad sectors (%"PRIuSEC" .. %"PRIuSEC")",
+ bad_hi - bad_lo, bad_lo, bad_hi);
+ if (mapfile) {
+ if (!mapfp) {
+ mapfp = fopen(mapfile, "w");
+ if (!mapfp)
+ bail_syserr(errno, "failed to open bad-sector map file `%s'",
+ optarg);
+ fprintf(mapfp, "## bad sector map\n\n");
+ }
+ fprintf(mapfp, "%"PRIuSEC" %"PRIuSEC"\n", bad_lo, bad_hi);
+ fflush(mapfp);
+ if (ferror(mapfp))
+ bail_syserr(errno, "error writing bad-sector map file");
+ }
+ if (lseek(outfd, (off_t)(bad_hi - bad_lo)*SECTORSZ, SEEK_CUR) < 0)
+ bail_syserr(errno, "failed to seek past bad sectors");
+ status = 1;
+ }
+ *pos_inout = bad_hi;
return (n);
}
{
#define BUFSECTORS 512
- int least, i;
+ int least;
unsigned char buf[BUFSECTORS*SECTORSZ];
secaddr pos;
- secaddr bad_lo, bad_hi, good, step;
size_t want;
ssize_t n;
static int first_time = 1;
struct file *f;
char fn[MAXFNSZ];
int act = -1;
+ int i;
#endif
least = least_live();
want = end - pos; if (want > BUFSECTORS) want = BUFSECTORS;
n = read_sectors(pos, buf, want);
- if (n <= 0) {
- report_bad_blocks_progress(pos, pos, errno);
- for (i = 0; i < 4; i++) {
- n = read_sectors(pos, buf, 1);
- if (n > 0) {
- clear_progress();
- moan("sector %"PRIuSEC" read ok after retry", pos);
- bad_lo = bad_hi = pos;
- goto recovered;
- }
- }
-
- bad_lo = pos; step = 1; bad_hi = pos + 1;
- for (;;) {
- report_bad_blocks_progress(bad_lo, bad_hi, errno);
- if (bad_hi >= end) {
- clear_progress();
- moan("giving up on this extent");
- n = 0; goto recovered;
- }
- step *= 2;
- if (step > end - bad_lo) step = end - bad_lo;
- pos = bad_lo + step - 1;
- n = read_sectors(pos, buf, 1);
- if (n > 0) break;
- bad_hi = pos + 1;
- }
-
- good = pos;
- while (good > bad_hi) {
- report_bad_blocks_progress(bad_lo, bad_hi, errno);
- pos = bad_hi + (good - bad_hi)/2;
- n = read_sectors(pos, buf, 1);
- if (n > 0) good = pos;
- else bad_hi = pos + 1;
- }
- recovered:
- if (bad_hi > bad_lo) {
- clear_progress();
- moan("skipping %"PRIuSEC" bad sectors (%"PRIuSEC" .. %"PRIuSEC")",
- bad_hi - bad_lo, bad_lo, bad_hi);
- if (mapfile) {
- if (!mapfp) {
- mapfp = fopen(mapfile, "w");
- if (!mapfp)
- bail_syserr(errno, "failed to open bad-sector map file `%s'",
- optarg);
- fprintf(mapfp, "## bad sector map\n\n");
- }
- fprintf(mapfp, "%"PRIuSEC" %"PRIuSEC"\n", bad_lo, bad_hi);
- fflush(mapfp);
- if (ferror(mapfp))
- bail_syserr(errno, "error writing bad-sector map file");
- }
- if (lseek(outfd, (off_t)(bad_hi - bad_lo)*SECTORSZ, SEEK_CUR) < 0)
- bail_syserr(errno, "failed to seek past bad sectors");
- status = 1;
- }
- pos = bad_hi;
- }
-
+ if (n <= 0) n = find_good_sector(&pos, end, buf, BUFSECTORS);
if (n > 0) { carefully_write(outfd, buf, n*SECTORSZ); pos += n; }
report_progress(pos); fflush(stdout);
}
~mdw / dvdrip / blobdiff