Ticket History #8485: Fix btree byte swapping for overflow data

Add known file test case for btree byte swap

Add a regression test for the preceding bugfix. This test uses btree
database files with known contents and byte orders with short keys and
overflow data items.

(back ported from commit af3e7a4ac8b49ae8047ae2be7070d32feb69217d)

https://github.com/krb5/krb5/commit/7e76a6eb8f738e7395766cc043c3755431bab718
Author: Tom Yu <tlyu@mit.edu>
Commit: 7e76a6eb8f738e7395766cc043c3755431bab718
Branch: krb5-1.14
.gitignore | 3 +
src/plugins/kdb/db2/libdb2/test/Makefile.in | 8 +++-
src/plugins/kdb/db2/libdb2/test/run.test | 26 ++++++++++-
src/plugins/kdb/db2/libdb2/test/t.be.txt | 64 +++++++++++++++++++++++++++
src/plugins/kdb/db2/libdb2/test/t.le.txt | 64 +++++++++++++++++++++++++++
5 files changed, 162 insertions(+), 3 deletions(-)

Fix btree byte swapping for overflow data

When operating on a btree database file of the opposite endianness,
libdb2 was swapping the wrong bytes if a record had a short key but
overflow data. Fix this bug by not incrementing p when swapping a
P_BIGKEY overflow pointer, and by always skipping the full key size
before swapping a P_BIGDATA overflow pointer (instead of assuming that
a P_BIGKEY pointer always precedes a P_BIGDATA pointer).

(cherry picked from commit b6238a61769ffbf8a8ac653baeed1c3373b961f8)

https://github.com/krb5/krb5/commit/b777b47bf7e24a44ae20065c28382e9a2d3834ef
Author: Tom Yu <tlyu@mit.edu>
Commit: b777b47bf7e24a44ae20065c28382e9a2d3834ef
Branch: krb5-1.13
src/plugins/kdb/db2/libdb2/btree/bt_conv.c | 15 +++++++++------
1 files changed, 9 insertions(+), 6 deletions(-)