X-Git-Url: http://git.rot13.org/?p=BackupPC.git;a=blobdiff_plain;f=lib%2FBackupPC%2FPoolWrite.pm;h=415c67f40776eda0e87412ad44bbc1ed6ded861c;hp=2cfd8dca5b9a2700a98977371a672124eb03b582;hb=5b79f9a3c01bca16dd4d211e76fc53daa549e421;hpb=79e0593c501fd58046feeca20c315cc4ac283435

diff --git a/lib/BackupPC/PoolWrite.pm b/lib/BackupPC/PoolWrite.pm
index 2cfd8dc..415c67f 100644
--- a/lib/BackupPC/PoolWrite.pm
+++ b/lib/BackupPC/PoolWrite.pm
@@ -38,7 +38,7 @@
 #   Craig Barratt  <cbarratt@users.sourceforge.net>
 #
 # COPYRIGHT
-#   Copyright (C) 2001-2003  Craig Barratt
+#   Copyright (C) 2001-2007  Craig Barratt
 #
 #   This program is free software; you can redistribute it and/or modify
 #   it under the terms of the GNU General Public License as published by
@@ -56,7 +56,7 @@
 #
 #========================================================================
 #
-# Version 2.1.0beta2, released 23 May 2004.
+# Version 3.1.0, released 25 Nov 2007.
 #
 # See http://backuppc.sourceforge.net.
 #
@@ -142,7 +142,19 @@ sub write
                 my $fileName = $a->{fileCnt} < 0 ? $a->{base}
                                         : "$a->{base}_$a->{fileCnt}";
                 last if ( !-f $fileName );
+                #
+                # Don't attempt to match pool files that already
+                # have too many hardlinks.  Also, don't match pool
+                # files with only one link since starting in
+                # BackupPC v3.0, BackupPC_nightly could be running
+                # in parallel (and removing those files).  This doesn't
+                # eliminate all possible race conditions, but just
+                # reduces the odds.  Other design steps eliminate
+                # the remaining race conditions of linking vs
+                # removing.
+                #
                 if ( (stat(_))[3] >= $a->{hardLinkMax}
+                    || (stat(_))[3] <= 1
 		    || !defined($fh = BackupPC::FileZIO->open($fileName, 0,
                                                      $a->{compress})) ) {
                     $a->{fileCnt}++;
@@ -352,13 +364,6 @@ sub write
 	}
     }
 
-    #
-    # Close the compare files
-    #
-    foreach my $f ( @{$a->{files}} ) {
-        $f->{fh}->close();
-    }
-
     if ( $a->{fileSize} == 0 ) {
         #
         # Simply create an empty file
@@ -370,9 +375,21 @@ sub write
         } else {
             close(OUT);
         }
+        #
+        # Close the compare files
+        #
+        foreach my $f ( @{$a->{files}} ) {
+            $f->{fh}->close();
+        }
         return (1, $a->{digest}, -s $a->{fileName}, $a->{errors});
     } elsif ( defined($a->{fhOut}) ) {
         $a->{fhOut}->close();
+        #
+        # Close the compare files
+        #
+        foreach my $f ( @{$a->{files}} ) {
+            $f->{fh}->close();
+        }
         return (0, $a->{digest}, -s $a->{fileName}, $a->{errors});
     } else {
         if ( @{$a->{files}} == 0 ) {
@@ -390,12 +407,51 @@ sub write
             #}
             #push(@{$a->{errors}}, $str);
         }
-        #print("   Linking $a->{fileName} to $a->{files}[0]->{name}\n");
-        if ( @{$a->{files}} && !link($a->{files}[0]->{name}, $a->{fileName}) ) {
-            push(@{$a->{errors}}, "Can't link $a->{fileName} to"
-                                . " $a->{files}[0]->{name}\n");
+        for ( my $i = 0 ; $i < @{$a->{files}} ; $i++ ) {
+            if ( link($a->{files}[$i]->{name}, $a->{fileName}) ) {
+                #print("  Linked $a->{fileName} to $a->{files}[$i]->{name}\n");
+                #
+                # Close the compare files
+                #
+                foreach my $f ( @{$a->{files}} ) {
+                    $f->{fh}->close();
+                }
+                return (1, $a->{digest}, -s $a->{fileName}, $a->{errors});
+            }
         }
-        return (1, $a->{digest}, -s $a->{fileName}, $a->{errors});
+        #
+        # We were unable to link to the pool.  Either we're at the
+        # hardlink max, or the pool file got deleted.  Recover by
+        # writing the matching file, since we still have an open
+        # handle.
+        #
+        for ( my $i = 0 ; $i < @{$a->{files}} ; $i++ ) {
+            if ( !$a->{files}[$i]->{fh}->rewind() ) {
+                push(@{$a->{errors}}, 
+                         "Unable to rewind $a->{files}[$i]->{name}"
+                       . " for copy after link fail\n");
+                next;
+            }
+            $a->{fhOut} = BackupPC::FileZIO->open($a->{fileName},
+                                            1, $a->{compress});
+            if ( !defined($a->{fhOut}) ) {
+                push(@{$a->{errors}},
+                        "Unable to open $a->{fileName}"
+                      . " for writing after link fail\n");
+            } else {
+                $a->filePartialCopy($a->{files}[$i]->{fh}, $a->{fhOut},
+                                    $a->{nWrite});
+                $a->{fhOut}->close;
+            }
+            last;
+        }
+        #
+        # Close the compare files
+        #
+        foreach my $f ( @{$a->{files}} ) {
+            $f->{fh}->close();
+        }
+        return (0, $a->{digest}, -s $a->{fileName}, $a->{errors});
     }
 }
 
@@ -494,4 +550,53 @@ sub filePartialCompare
     return 1;
 }
 
+#
+# LinkOrCopy() does a hardlink from oldFile to newFile.
+#
+# If that fails (because there are too many links on oldFile)
+# then oldFile is copied to newFile, and the pool stats are
+# returned to be added to the new file list.  That allows
+# BackupPC_link to try again, and to create a new pool file
+# if necessary.
+#
+sub LinkOrCopy
+{
+    my($bpc, $oldFile, $oldFileComp, $newFile, $newFileComp) = @_;
+    my($nRead, $data);
+
+    unlink($newFile)  if ( -f $newFile );
+    #
+    # Try to link if hardlink limit is ok, and compression types
+    # are the same
+    #
+    return (1, undef) if ( (stat($oldFile))[3] < $bpc->{Conf}{HardLinkMax}
+                            && !$oldFileComp == !$newFileComp
+                            && link($oldFile, $newFile) );
+    #
+    # There are too many links on oldFile, or compression
+    # type if different, so now we have to copy it.
+    #
+    # We need to compute the file size, which is expensive
+    # since we need to read the file twice.  That's probably
+    # ok since the hardlink limit is rarely hit.
+    #
+    my $readFd = BackupPC::FileZIO->open($oldFile, 0, $oldFileComp);
+    if ( !defined($readFd) ) {
+        return (0, undef, undef, undef, ["LinkOrCopy: can't open $oldFile"]);
+    }
+    while ( $readFd->read(\$data, $BufSize) > 0 ) {
+        $nRead += length($data);
+    }
+    $readFd->rewind();
+
+    my $poolWrite = BackupPC::PoolWrite->new($bpc, $newFile,
+                                             $nRead, $newFileComp);
+    while ( $readFd->read(\$data, $BufSize) > 0 ) {
+        $poolWrite->write(\$data);
+    }
+    my($exists, $digest, $outSize, $errs) = $poolWrite->close;
+
+    return ($exists, $digest, $nRead, $outSize, $errs);
+}
+
 1;