$|=1;
+# Check to see whether the tape.nn and fsys.nn files are sane.
+# checkallused checks that all the filesystems mounted are in fact
+# dumped in both full and incremental dumps.
+setstatus "FAILED configuration check";
print "Configuration check ...\n" or die $!;
system 'checkallused'; $? and die $?;
printdate();
+setstatus "FAILED reading TAPEID";
+# Try to read the tape ID from the tape into the file TAPEID
unlink 'TAPEID';
system "mt -f $tape rewind"; $? and die $?;
system "mt -f $tape setblk $blocksizebytes"; $? and die $?;
setstatus "FAILED during startup";
+# We need some ID; if the tape has one already that takes precedence;
+# otherwise the user might have set a tape ID that this should be
+# by creating really-TAPEID.
if (open T, "TAPEID") {
unlink 'really-TAPEID';
} elsif (open T, "really-TAPEID") {
die "No TAPEID.\n";
}
+# read the ID; it had better be a non-empty string of alphanumeric chars.
chomp($tapeid= <T>);
$tapeid =~ m/[^0-9a-zA-Z]/ and die "Bad TAPEID ($&).\n";
$tapeid =~ m/[0-9a-zA-Z]/ or die "Empty TAPEID.\n";
setstatus "FAILED at tape identity check";
+# We don't let the user overwrite the tape used for the last backup.
if (open L, "last-tape") {
chomp($lasttape= <L>);
close L;
die "Tape $tapeid same as last time.\n" if $tapeid eq $lasttape;
+# $tapeid identifies the individual tape; $tapedesc is its current
+# identity and function, for printing in messages. You can make these
+# namespaces the same if you like, or you can make the tape.<tapeid>
+# files be links to tape.<tapedesc> files.
if (defined($tapedesc= readlink "$etc/tape.$tapeid")) {
$tapedesc =~ s/^.*\.//;
$tapedesc .= "($tapeid)";
$tapedesc = $tapeid;
}
+# Parse the appropriate tape.nn file.
+# Format is: empty lines and lines starting '#' are ignored. Trailing
+# whitespace is ignored. File must end with 'end' on a line by itself.
+# Either there should be a line 'incremental' to indicate that this is
+# a tape for incremental backups, or a pair of lines 'filesystems fsg'
+# and 'next tapeid', indicating that this tape is part of a full
+# backup, containing the filesystem group fsg.
undef $fsys;
open D, "$etc/tape.$tapeid" or die "Unknown tape $tapeid ($!).\n";
for (;;) {
}
close D or die $!;
+# Incremental backups are handled by increm, not us.
if ($incremental) {
die "incremental tape $tapeid has next or filesystems\n"
if defined($next) || defined($fsys);
die $!;
}
+# Read the filesystem group definition (file fsys.nnn)
readfsys("$fsys");
openlog();
$doing= "dump of $fsys to tape $tapedesc in drive $tape";
print LOG "$doing:\n" or die $!;
+setstatus "FAILED writing tape ID";
+# First write the tape ID to this tape.
open T, ">TAPEID" or die $!;
-print T "$tapeid\n$tapedesc\n" or die $!;
+print T "$tapeid\n" or die $!;
close T or die $!;
system "tar -b$blocksize -vvcf TAPEID.tar TAPEID"; $? and die $?;
close(DUMPOW); close(TEEOW); close(BUFOW); close(FINDOW);
}
+# work out a find option string that will exclude the required files
+# Note that dump pays no attention to exclude options.
+$exclopt = '';
+foreach $exc (@excldir) {
+ $exclopt .= "-regex $exc -prune -o ";
+}
+foreach $exc (@excl) {
+ $exclopt .= "-regex $exc -o ";
+}
+
+# For each filesystem to be put on this tape:
for $tf (@fsys) {
printdate();
pipe(FINDOR,FINDOW) or die $!;
pipe(TEEOR,TEEOW) or die $!;
pipe(BUFOR,BUFOW) or die $!;
parsefsys();
+
+ # We can back up via dump or cpio or zafio
if ($tm eq 'dump') {
$dumpcmd= "dump 0bfu $softblocksizekb - $atf";
$dumpin= '</dev/null';
- } else {
+ } elsif ($tm eq 'cpio') {
startprocess '</dev/null','>&FINDOW',$rstr."find $atf -xdev -noleaf -print0";
$dumpcmd= "cpio -Hustar -o0C$softblocksizebytes";
$dumpin= '<&FINDOR';
+ } elsif ($tm eq 'zafio') {
+ # compress-each-file-then-archive using afio
+ startprocess '</dev/null','>&FINDOW',$rstr."find $atf -xdev -noleaf $exclopt -print";
+ # don't use verbose flag as this generates 2MB report emails :->
+ $dumpcmd = "afio -b $softblocksizebytes -Zo -";
+ $dumpin = '<&FINDOR';
+ } else {
+ die "unknown method $tm for $prefix:$atf\n";
}
+ # This is a funky way of doing a pipeline which pays attention
+ # to the exit status of all the commands in the pipeline.
+ # It is roughly equivalent to:
+ # md5sum <p >>this-md5sums
+ # dump <$dumpin | tee p | writebuffer | dd >/dev/null
startprocess '<p','>>this-md5sums','md5sum';
startprocess $dumpin,'>&DUMPOW',$rstr.$dumpcmd;
startprocess '<&DUMPOR','>&TEEOW','tee p';
endprocesses();
}
+# The backup should now be complete; verify it
+
setstatus "FAILED during check";
+# Rewind the tape and skip the TAPEID record
system "mt -f $tape rewind"; $? and die $?;
system "mt -f $ntape fsf 1"; $? and die $?;
+# Check the md5sums match for each filesystem on the tape
open S,"this-md5sums" or die $!;
for $tf (@fsys) {
printdate();
chomp($orgsum= <S>);
$orgsum =~ m/^[0-9a-fA-F]{32}$/i or die "orgsum \`$orgsum' ?";
- chomp($csum= `readbuffer <$ntape | md5sum`);
+ chomp($csum= `dd if=$ntape ibs=$blocksizebytes | readbuffer | md5sum`);
$orgsum eq $csum or die "MISMATCH $tf $csum $orgsum\n";
print "checksum ok $csum\t$tf\n" or die $!;
print LOG "checksum ok $csum\t$tf\n" or die $!;
setstatus "FAILED during cleanup";
+# Write to some status files to indicate what the backup system
+# ought to do when next invoked.
+# reset incremental backup count to 1.
open IAN,">increm-advance.new" or die $!;
print IAN "1\n" or die $!;
close IAN or die $!;
+# Next full backup is whatever the next link in the tape description
+# file says it ought to be.
open TN,">next-full.new" or die $!;
print TN "$next\n" or die $!;
close TN or die $!;
unlink 'last-tape','next-full';
+# We are the last tape to have been backed up
rename 'TAPEID','last-tape' or die $!;
rename 'this-md5sums',"md5sums.$fsys" or die $!;
rename 'log',"log.$fsys" or die $!;
~ian / chiark-utils.git / blobdiff