X-Git-Url: https://git.distorted.org.uk/~mdw/dvdrip/blobdiff_plain/513eba4411f9c6f8b09375734fdaafc49a962eae..0f0ba33faf1e5109b2826c1c343ab13e618782c3:/dvd-sector-copy.c?ds=sidebyside

diff --git a/dvd-sector-copy.c b/dvd-sector-copy.c
index 28a4943..bbe0c10 100644
--- a/dvd-sector-copy.c
+++ b/dvd-sector-copy.c
@@ -415,9 +415,11 @@ static int compare_badblock(const void *a, const void *b)
 
 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
@@ -440,22 +442,95 @@ static ssize_t read_sectors(secaddr pos, void *buf, secaddr want)
     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);
 }
 
@@ -463,10 +538,9 @@ static void emit(secaddr start, secaddr end)
 {
 #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;
@@ -474,6 +548,7 @@ static void emit(secaddr start, secaddr end)
   struct file *f;
   char fn[MAXFNSZ];
   int act = -1;
+  int i;
 #endif
 
   least = least_live();
@@ -521,67 +596,7 @@ static void emit(secaddr start, secaddr end)
     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);
   }