use Fcntl qw( :DEFAULT :flock :seek );
sub precalc_sizes {
- ##
- # Precalculate index, bucket and bucket list sizes
- ##
+ ##
+ # Precalculate index, bucket and bucket list sizes
+ ##
my $self = shift;
$self->{index_size} = (2**8) * $self->{long_size};
}
sub set_pack {
- ##
- # Set pack/unpack modes (see file header for more)
- ##
+ ##
+ # Set pack/unpack modes (see file header for more)
+ ##
my $self = shift;
my ($long_s, $long_p, $data_s, $data_p) = @_;
##
# Set to 4 and 'N' for 32-bit offset tags (default). Theoretical limit of 4 GB per file.
- # (Perl must be compiled with largefile support for files > 2 GB)
+ # (Perl must be compiled with largefile support for files > 2 GB)
#
# Set to 8 and 'Q' for 64-bit offsets. Theoretical limit of 16 XB per file.
- # (Perl must be compiled with largefile and 64-bit long support)
+ # (Perl must be compiled with largefile and 64-bit long support)
##
$self->{long_size} = $long_s ? $long_s : 4;
$self->{long_pack} = $long_p ? $long_p : 'N';
$self->{data_size} = $data_s ? $data_s : 4;
$self->{data_pack} = $data_p ? $data_p : 'N';
- return $self->precalc_sizes();
+ return $self->precalc_sizes();
}
sub set_digest {
- ##
- # Set key digest function (default is MD5)
- ##
+ ##
+ # Set key digest function (default is MD5)
+ ##
my $self = shift;
my ($digest_func, $hash_size) = @_;
$self->{digest} = $digest_func ? $digest_func : \&Digest::MD5::md5;
$self->{hash_size} = $hash_size ? $hash_size : 16;
- return $self->precalc_sizes();
+ return $self->precalc_sizes();
}
sub new {
}
sub get_bucket_value {
- ##
- # Fetch single value given tag and MD5 digested key.
- ##
- my $self = shift;
- my ($obj, $tag, $md5) = @_;
- my $keys = $tag->{content};
+ ##
+ # Fetch single value given tag and MD5 digested key.
+ ##
+ my $self = shift;
+ my ($obj, $tag, $md5) = @_;
+ my $keys = $tag->{content};
my $fh = $obj->_fh;
- ##
- # Iterate through buckets, looking for a key match
- ##
+ ##
+ # Iterate through buckets, looking for a key match
+ ##
BUCKET:
- for (my $i=0; $i<$self->{max_buckets}; $i++) {
- my $key = substr($keys, $i * $self->{bucket_size}, $self->{hash_size});
- my $subloc = unpack($self->{long_pack}, substr($keys, ($i * $self->{bucket_size}) + $self->{hash_size}, $self->{long_size}));
+ for (my $i=0; $i<$self->{max_buckets}; $i++) {
+ my $key = substr($keys, $i * $self->{bucket_size}, $self->{hash_size});
+ my $subloc = unpack($self->{long_pack}, substr($keys, ($i * $self->{bucket_size}) + $self->{hash_size}, $self->{long_size}));
- if (!$subloc) {
- ##
- # Hit end of list, no match
- ##
- return;
- }
+ if (!$subloc) {
+ ##
+ # Hit end of list, no match
+ ##
+ return;
+ }
if ( $md5 ne $key ) {
next BUCKET;
# Key exists, but content is null
##
else { return; }
- } # i loop
+ } # i loop
- return;
+ return;
}
sub delete_bucket {
- ##
- # Delete single key/value pair given tag and MD5 digested key.
- ##
- my $self = shift;
- my ($obj, $tag, $md5) = @_;
- my $keys = $tag->{content};
+ ##
+ # Delete single key/value pair given tag and MD5 digested key.
+ ##
+ my $self = shift;
+ my ($obj, $tag, $md5) = @_;
+ my $keys = $tag->{content};
my $fh = $obj->_fh;
-
- ##
- # Iterate through buckets, looking for a key match
- ##
+
+ ##
+ # Iterate through buckets, looking for a key match
+ ##
BUCKET:
- for (my $i=0; $i<$self->{max_buckets}; $i++) {
- my $key = substr($keys, $i * $self->{bucket_size}, $self->{hash_size});
- my $subloc = unpack($self->{long_pack}, substr($keys, ($i * $self->{bucket_size}) + $self->{hash_size}, $self->{long_size}));
+ for (my $i=0; $i<$self->{max_buckets}; $i++) {
+ my $key = substr($keys, $i * $self->{bucket_size}, $self->{hash_size});
+ my $subloc = unpack($self->{long_pack}, substr($keys, ($i * $self->{bucket_size}) + $self->{hash_size}, $self->{long_size}));
- if (!$subloc) {
- ##
- # Hit end of list, no match
- ##
- return;
- }
+ if (!$subloc) {
+ ##
+ # Hit end of list, no match
+ ##
+ return;
+ }
if ( $md5 ne $key ) {
next BUCKET;
print( $fh chr(0) x $self->{bucket_size} );
return 1;
- } # i loop
+ } # i loop
- return;
+ return;
}
sub bucket_exists {
- ##
- # Check existence of single key given tag and MD5 digested key.
- ##
- my $self = shift;
- my ($obj, $tag, $md5) = @_;
- my $keys = $tag->{content};
-
- ##
- # Iterate through buckets, looking for a key match
- ##
+ ##
+ # Check existence of single key given tag and MD5 digested key.
+ ##
+ my $self = shift;
+ my ($obj, $tag, $md5) = @_;
+ my $keys = $tag->{content};
+
+ ##
+ # Iterate through buckets, looking for a key match
+ ##
BUCKET:
- for (my $i=0; $i<$self->{max_buckets}; $i++) {
- my $key = substr($keys, $i * $self->{bucket_size}, $self->{hash_size});
- my $subloc = unpack($self->{long_pack}, substr($keys, ($i * $self->{bucket_size}) + $self->{hash_size}, $self->{long_size}));
+ for (my $i=0; $i<$self->{max_buckets}; $i++) {
+ my $key = substr($keys, $i * $self->{bucket_size}, $self->{hash_size});
+ my $subloc = unpack($self->{long_pack}, substr($keys, ($i * $self->{bucket_size}) + $self->{hash_size}, $self->{long_size}));
- if (!$subloc) {
- ##
- # Hit end of list, no match
- ##
- return;
- }
+ if (!$subloc) {
+ ##
+ # Hit end of list, no match
+ ##
+ return;
+ }
if ( $md5 ne $key ) {
next BUCKET;
# Matched key -- return true
##
return 1;
- } # i loop
+ } # i loop
- return;
+ return;
}
sub find_bucket_list {
- ##
- # Locate offset for bucket list, given digested key
- ##
- my $self = shift;
- my ($obj, $md5) = @_;
-
- ##
- # Locate offset for bucket list using digest index system
- ##
- my $ch = 0;
- my $tag = $self->load_tag($obj, $obj->_base_offset);
- if (!$tag) { return; }
-
- while ($tag->{signature} ne DBM::Deep->SIG_BLIST) {
- $tag = $self->index_lookup($obj, $tag, ord(substr($md5, $ch, 1)));
- if (!$tag) { return; }
- $ch++;
- }
-
- return $tag;
+ ##
+ # Locate offset for bucket list, given digested key
+ ##
+ my $self = shift;
+ my ($obj, $md5) = @_;
+
+ ##
+ # Locate offset for bucket list using digest index system
+ ##
+ my $ch = 0;
+ my $tag = $self->load_tag($obj, $obj->_base_offset);
+ if (!$tag) { return; }
+
+ while ($tag->{signature} ne DBM::Deep->SIG_BLIST) {
+ $tag = $self->index_lookup($obj, $tag, ord(substr($md5, $ch, 1)));
+ if (!$tag) { return; }
+ $ch++;
+ }
+
+ return $tag;
}
sub traverse_index {
- ##
- # Scan index and recursively step into deeper levels, looking for next key.
- ##
+ ##
+ # Scan index and recursively step into deeper levels, looking for next key.
+ ##
my $self = shift;
my ($obj, $offset, $ch, $force_return_next) = @_;
$force_return_next = undef unless $force_return_next;
-
- my $tag = $self->load_tag($obj, $offset );
+
+ my $tag = $self->load_tag($obj, $offset );
my $fh = $obj->_fh;
-
- if ($tag->{signature} ne DBM::Deep->SIG_BLIST) {
- my $content = $tag->{content};
- my $start;
- if ($obj->{return_next}) { $start = 0; }
- else { $start = ord(substr($obj->{prev_md5}, $ch, 1)); }
-
- for (my $index = $start; $index < 256; $index++) {
- my $subloc = unpack($self->{long_pack}, substr($content, $index * $self->{long_size}, $self->{long_size}) );
- if ($subloc) {
- my $result = $self->traverse_index( $obj, $subloc, $ch + 1, $force_return_next );
- if (defined($result)) { return $result; }
- }
- } # index loop
-
- $obj->{return_next} = 1;
- } # tag is an index
-
- elsif ($tag->{signature} eq DBM::Deep->SIG_BLIST) {
- my $keys = $tag->{content};
- if ($force_return_next) { $obj->{return_next} = 1; }
-
- ##
- # Iterate through buckets, looking for a key match
- ##
- for (my $i=0; $i<$self->{max_buckets}; $i++) {
- my $key = substr($keys, $i * $self->{bucket_size}, $self->{hash_size});
- my $subloc = unpack($self->{long_pack}, substr($keys, ($i * $self->{bucket_size}) + $self->{hash_size}, $self->{long_size}));
-
- if (!$subloc) {
- ##
- # End of bucket list -- return to outer loop
- ##
- $obj->{return_next} = 1;
- last;
- }
- elsif ($key eq $obj->{prev_md5}) {
- ##
- # Located previous key -- return next one found
- ##
- $obj->{return_next} = 1;
- next;
- }
- elsif ($obj->{return_next}) {
- ##
- # Seek to bucket location and skip over signature
- ##
- seek($fh, $subloc + DBM::Deep->SIG_SIZE + $obj->_root->{file_offset}, SEEK_SET);
-
- ##
- # Skip over value to get to plain key
- ##
- my $size;
- read( $fh, $size, $self->{data_size}); $size = unpack($self->{data_pack}, $size);
- if ($size) { seek($fh, $size, SEEK_CUR); }
-
- ##
- # Read in plain key and return as scalar
- ##
- my $plain_key;
- read( $fh, $size, $self->{data_size}); $size = unpack($self->{data_pack}, $size);
- if ($size) { read( $fh, $plain_key, $size); }
-
- return $plain_key;
- }
- } # bucket loop
-
- $obj->{return_next} = 1;
- } # tag is a bucket list
-
- return;
+
+ if ($tag->{signature} ne DBM::Deep->SIG_BLIST) {
+ my $content = $tag->{content};
+ my $start;
+ if ($obj->{return_next}) { $start = 0; }
+ else { $start = ord(substr($obj->{prev_md5}, $ch, 1)); }
+
+ for (my $index = $start; $index < 256; $index++) {
+ my $subloc = unpack($self->{long_pack}, substr($content, $index * $self->{long_size}, $self->{long_size}) );
+ if ($subloc) {
+ my $result = $self->traverse_index( $obj, $subloc, $ch + 1, $force_return_next );
+ if (defined($result)) { return $result; }
+ }
+ } # index loop
+
+ $obj->{return_next} = 1;
+ } # tag is an index
+
+ elsif ($tag->{signature} eq DBM::Deep->SIG_BLIST) {
+ my $keys = $tag->{content};
+ if ($force_return_next) { $obj->{return_next} = 1; }
+
+ ##
+ # Iterate through buckets, looking for a key match
+ ##
+ for (my $i=0; $i<$self->{max_buckets}; $i++) {
+ my $key = substr($keys, $i * $self->{bucket_size}, $self->{hash_size});
+ my $subloc = unpack($self->{long_pack}, substr($keys, ($i * $self->{bucket_size}) + $self->{hash_size}, $self->{long_size}));
+
+ if (!$subloc) {
+ ##
+ # End of bucket list -- return to outer loop
+ ##
+ $obj->{return_next} = 1;
+ last;
+ }
+ elsif ($key eq $obj->{prev_md5}) {
+ ##
+ # Located previous key -- return next one found
+ ##
+ $obj->{return_next} = 1;
+ next;
+ }
+ elsif ($obj->{return_next}) {
+ ##
+ # Seek to bucket location and skip over signature
+ ##
+ seek($fh, $subloc + DBM::Deep->SIG_SIZE + $obj->_root->{file_offset}, SEEK_SET);
+
+ ##
+ # Skip over value to get to plain key
+ ##
+ my $size;
+ read( $fh, $size, $self->{data_size}); $size = unpack($self->{data_pack}, $size);
+ if ($size) { seek($fh, $size, SEEK_CUR); }
+
+ ##
+ # Read in plain key and return as scalar
+ ##
+ my $plain_key;
+ read( $fh, $size, $self->{data_size}); $size = unpack($self->{data_pack}, $size);
+ if ($size) { read( $fh, $plain_key, $size); }
+
+ return $plain_key;
+ }
+ } # bucket loop
+
+ $obj->{return_next} = 1;
+ } # tag is a bucket list
+
+ return;
}
sub get_next_key {
- ##
- # Locate next key, given digested previous one
- ##
+ ##
+ # Locate next key, given digested previous one
+ ##
my $self = shift;
my ($obj) = @_;
-
- $obj->{prev_md5} = $_[1] ? $_[1] : undef;
- $obj->{return_next} = 0;
-
- ##
- # If the previous key was not specifed, start at the top and
- # return the first one found.
- ##
- if (!$obj->{prev_md5}) {
- $obj->{prev_md5} = chr(0) x $self->{hash_size};
- $obj->{return_next} = 1;
- }
-
- return $self->traverse_index( $obj, $obj->_base_offset, 0 );
+
+ $obj->{prev_md5} = $_[1] ? $_[1] : undef;
+ $obj->{return_next} = 0;
+
+ ##
+ # If the previous key was not specifed, start at the top and
+ # return the first one found.
+ ##
+ if (!$obj->{prev_md5}) {
+ $obj->{prev_md5} = chr(0) x $self->{hash_size};
+ $obj->{return_next} = 1;
+ }
+
+ return $self->traverse_index( $obj, $obj->_base_offset, 0 );
}
1;
projects / dbsrgits/DBM-Deep.git / blobdiff