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Postings from May 2002
Re: perl@16433
From:
Nicholas Clark
Date:
May 6, 2002 16:24
Subject:
Re: perl@16433
Message ID:
20020506232146.GF4698@Bagpuss.unfortu.net
On Mon, May 06, 2002 at 05:50:38PM +0300, Jarkko Hietaniemi wrote:
> - Storable finishing touches [Nicholas]
This is half of the finishing touches.
This makes Storable default to accepting files with future minor version
numbers. This will make upgrading Storable in the future less painful that
it currently is.
If the other half of the finishing touches (plugging the failure to free the
keybuf and membuf in the context structure) can't easily be solved in a way
that works on pre 5.7.3 then I believe that this Storable is good enough to
be the next CPAN release.
Dan - what version did you think Storable.pm should now be?
Can anyone see anything else that would suggest not releasing this Storable
to CPAN?
Potential backwards incompatible change - the set-by-perl context variables
are re-read per call into Storable, rather than once per thread.
This lets the user localise them and change their value from perl with the
expected behaviour.
Nicholas Clark
--
Even better than the real thing: http://nms-cgi.sourceforge.net/
--- ext/Storable/Storable.pm.orig Thu May 2 10:28:00 2002
+++ ext/Storable/Storable.pm Mon May 6 22:39:14 2002
@@ -102,6 +102,7 @@
# By default restricted hashes are downgraded on earlier perls.
$Storable::downgrade_restricted = 1;
+$Storable::accept_future_minor = 1;
bootstrap Storable;
1;
__END__
@@ -589,6 +590,25 @@
placeholder keys and leaving the keys and all values unlocked. To make
Storable C<croak()> instead, set C<$Storable::downgrade_restricted> to
a false value. To restore the default set it back to some C<TRUE> value.
+
+=item files from future versions of Storable
+
+Earlier versions of Storable would immediately croak if they encountered
+a file with a higher internal version number than the reading Storable
+knew about. Internal version numbers are increased each time new data
+types (such as restricted hashes) are added to the vocabulary of the file
+format. This meant that a newer Storable module had no way of writing a
+file readable by an older Storable, even if writer didn't store newer
+data types.
+
+This version of Storable will defer croaking until it encounters a data
+type in the file that it does not recognize. This means that it will
+continue to read files generated by newer Storable modules which are careful
+in what they write out, making it easier to upgrade Storable modules in a
+mixed environment.
+
+The old behaviour of immediate croaking can be re-instated by setting
+C<$Storable::accept_future_minor> to false.
=back
--- ext/Storable/Storable.xs.orig Sun May 5 17:54:19 2002
+++ ext/Storable/Storable.xs Mon May 6 23:48:45 2002
@@ -59,7 +59,7 @@
#include <XSUB.h>
#ifndef NETWARE
-#if 1
+#if 0
#define DEBUGME /* Debug mode, turns assertions on as well */
#define DASSERT /* Assertion mode */
#endif
@@ -339,6 +339,7 @@
#ifndef HAS_UTF8_ALL
int use_bytes; /* whether to bytes-ify utf8 */
#endif
+ int accept_future_minor; /* croak immediately on future minor versions? */
int s_dirty; /* context is dirty due to CROAK() -- can be cleaned */
int membuf_ro; /* true means membuf is read-only and msaved is rw */
struct extendable keybuf; /* for hash key retrieval */
@@ -1204,6 +1205,9 @@
sv_free((SV *) hook_seen);
}
+ cxt->forgive_me = -1; /* Fetched from perl if needed */
+ cxt->canonical = -1; /* Idem */
+
reset_context(cxt);
}
@@ -1249,6 +1253,7 @@
#ifndef HAS_UTF8_ALL
cxt->use_bytes = -1; /* Fetched from perl if needed */
#endif
+ cxt->accept_future_minor = -1; /* Fetched from perl if needed */
}
/*
@@ -1290,6 +1295,14 @@
sv_free((SV *) hseen); /* optional HV, for backward compat. */
}
+#ifndef HAS_RESTRICTED_HASHES
+ cxt->derestrict = -1; /* Fetched from perl if needed */
+#endif
+#ifndef HAS_UTF8_ALL
+ cxt->use_bytes = -1; /* Fetched from perl if needed */
+#endif
+ cxt->accept_future_minor = -1; /* Fetched from perl if needed */
+
reset_context(cxt);
}
@@ -4891,12 +4904,26 @@
(version_major == STORABLE_BIN_MAJOR &&
version_minor > STORABLE_BIN_MINOR)
) {
- TRACEME(("but I am version is %d.%d", STORABLE_BIN_MAJOR,
- STORABLE_BIN_MINOR));
-
+ int croak_now = 1;
+ TRACEME(("but I am version is %d.%d", STORABLE_BIN_MAJOR,
+ STORABLE_BIN_MINOR));
+
+ if (version_major == STORABLE_BIN_MAJOR) {
+ TRACEME(("cxt->accept_future_minor is %d",
+ cxt->accept_future_minor));
+ if (cxt->accept_future_minor < 0)
+ cxt->accept_future_minor
+ = (SvTRUE(perl_get_sv("Storable::accept_future_minor",
+ TRUE))
+ ? 1 : 0);
+ if (cxt->accept_future_minor == 1)
+ croak_now = 0; /* Don't croak yet. */
+ }
+ if (croak_now) {
CROAK(("Storable binary image v%d.%d more recent than I am (v%d.%d)",
- version_major, version_minor,
- STORABLE_BIN_MAJOR, STORABLE_BIN_MINOR));
+ version_major, version_minor,
+ STORABLE_BIN_MAJOR, STORABLE_BIN_MINOR));
+ }
}
/*
@@ -5034,7 +5061,19 @@
TRACEME(("had retrieved #%d at 0x%"UVxf, tag, PTR2UV(sv)));
SvREFCNT_inc(sv); /* One more reference to this same sv */
return sv; /* The SV pointer where object was retrieved */
- }
+ } else if (type >= SX_ERROR && cxt->ver_minor > STORABLE_BIN_MINOR) {
+ if (cxt->accept_future_minor < 0)
+ cxt->accept_future_minor
+ = (SvTRUE(perl_get_sv("Storable::accept_future_minor",
+ TRUE))
+ ? 1 : 0);
+ if (cxt->accept_future_minor == 1) {
+ CROAK(("Storable binary image v%d.%d contains data of type %d. "
+ "This Storable is v%d.%d and can only handle data types up to %d",
+ cxt->ver_major, cxt->ver_minor, type,
+ STORABLE_BIN_MAJOR, STORABLE_BIN_MINOR, SX_ERROR - 1));
+ }
+ }
first_time: /* Will disappear when support for old format is dropped */
--- ext/Storable/t/malice.t.orig Thu May 2 14:48:29 2002
+++ ext/Storable/t/malice.t Mon May 6 23:50:50 2002
@@ -48,7 +48,7 @@
# for network order, and 2 tests per byte on the 'pst0' "magic number" only
# present in files, but not in things store()ed to memory
$fancy = ($] > 5.007 ? 2 : 0);
- plan tests => 334 + length($Config{byteorder}) * 4 + $fancy * 8;
+ plan tests => 378 + length($Config{byteorder}) * 4 + $fancy * 8;
}
use Storable qw (store retrieve freeze thaw nstore nfreeze);
@@ -174,9 +174,17 @@
# )
my $minor4 = $header->{minor} + 4;
substr ($copy, $file_magic + 1, 1) = chr $minor4;
- test_corrupt ($copy, $sub,
- "/^Storable binary image v$header->{major}\.$minor4 more recent than I am \\(v$header->{major}\.$minor\\)/",
- "higher minor");
+ {
+ # Now by default newer minor version numbers are not a pain.
+ $clone = &$sub($copy);
+ ok ($@, "", "by default no error on higher minor");
+ test_hash ($clone);
+
+ local $Storable::accept_future_minor = 0;
+ test_corrupt ($copy, $sub,
+ "/^Storable binary image v$header->{major}\.$minor4 more recent than I am \\(v$header->{major}\.$minor\\)/",
+ "higher minor");
+ }
$copy = $contents;
my $major1 = $header->{major} + 1;
@@ -224,6 +232,29 @@
test_corrupt ($copy, $sub,
"/^Corrupted storable $what \\(binary v$header->{major}.$header->{minor}\\)/",
"bogus tag");
+
+ # Now drop the minor version number
+ substr ($copy, $file_magic + 1, 1) = chr $minor1;
+
+ test_corrupt ($copy, $sub,
+ "/^Corrupted storable $what \\(binary v$header->{major}.$minor1\\)/",
+ "bogus tag, minor less 1");
+ # Now increase the minor version number
+ substr ($copy, $file_magic + 1, 1) = chr $minor4;
+
+ # local $Storable::DEBUGME = 1;
+ # This is the delayed croak
+ test_corrupt ($copy, $sub,
+ "/^Storable binary image v$header->{major}.$minor4 contains data of type 255. This Storable is v$header->{major}.$header->{minor} and can only handle data types up to 25/",
+ "bogus tag, minor plus 4");
+ # And check again that this croak is not delayed:
+ {
+ # local $Storable::DEBUGME = 1;
+ local $Storable::accept_future_minor = 0;
+ test_corrupt ($copy, $sub,
+ "/^Storable binary image v$header->{major}\.$minor4 more recent than I am \\(v$header->{major}\.$minor\\)/",
+ "higher minor");
+ }
}
sub slurp {