pgsql: Move the backup-block logic from XLogInsert to a new file, xlogi

Move the backup-block logic from XLogInsert to a new file, xloginsert.c.

xlog.c is huge, this makes it a little bit smaller, which is nice. Functions
related to putting together the WAL record are in xloginsert.c, and the
lower level stuff for managing WAL buffers and such are in xlog.c.

Also move the definition of XLogRecord to a separate header file. This
causes churn in the #includes of all the files that write WAL records, and
redo routines, but it avoids pulling in xlog.h into most places.

Reviewed by Michael Paquier, Alvaro Herrera, Andres Freund and Amit Kapila.

Branch
------
master

Details
-------
http://git.postgresql.org/pg/commitdiff/2076db2aea766c4c828dccc34ae35f614129000d

Modified Files
--------------
contrib/pg_xlogdump/pg_xlogdump.c       |    2 +-
doc/src/sgml/wal.sgml                   |   14 +-
src/backend/access/gin/ginbtree.c       |    1 +
src/backend/access/gin/gindatapage.c    |    1 +
src/backend/access/gin/ginentrypage.c   |    1 +
src/backend/access/gin/ginfast.c        |    1 +
src/backend/access/gin/gininsert.c      |    1 +
src/backend/access/gin/ginutil.c        |    1 +
src/backend/access/gin/ginvacuum.c      |    1 +
src/backend/access/gist/gistbuild.c     |    1 +
src/backend/access/gist/gistxlog.c      |    1 +
src/backend/access/heap/heapam.c        |    2 +
src/backend/access/heap/pruneheap.c     |    1 +
src/backend/access/heap/rewriteheap.c   |    1 +
src/backend/access/heap/visibilitymap.c |    1 +
src/backend/access/nbtree/nbtinsert.c   |    1 +
src/backend/access/nbtree/nbtpage.c     |    2 +
src/backend/access/nbtree/nbtree.c      |    1 +
src/backend/access/nbtree/nbtsort.c     |    2 +
src/backend/access/nbtree/nbtxlog.c     |    2 +
src/backend/access/spgist/spgdoinsert.c |    1 +
src/backend/access/spgist/spginsert.c   |    2 +
src/backend/access/spgist/spgvacuum.c   |    1 +
src/backend/access/spgist/spgxlog.c     |    1 +
src/backend/access/transam/Makefile     |    2 +-
src/backend/access/transam/clog.c       |    3 +
src/backend/access/transam/multixact.c  |    2 +
src/backend/access/transam/twophase.c   |    1 +
src/backend/access/transam/varsup.c     |    1 +
src/backend/access/transam/xact.c       |    2 +
src/backend/access/transam/xlog.c       |  761 +++----------------------------
src/backend/access/transam/xloginsert.c |  633 +++++++++++++++++++++++++
src/backend/access/transam/xlogreader.c |    2 +-
src/backend/access/transam/xlogutils.c  |  121 +++++
src/backend/catalog/heap.c              |    1 +
src/backend/catalog/namespace.c         |    1 +
src/backend/catalog/storage.c           |    2 +
src/backend/commands/cluster.c          |    1 +
src/backend/commands/copy.c             |    1 +
src/backend/commands/createas.c         |    1 +
src/backend/commands/dbcommands.c       |    1 +
src/backend/commands/matview.c          |    1 +
src/backend/commands/sequence.c         |    2 +
src/backend/commands/tablecmds.c        |    1 +
src/backend/commands/tablespace.c       |    2 +
src/backend/commands/vacuumlazy.c       |    1 +
src/backend/commands/variable.c         |    1 +
src/backend/storage/buffer/bufmgr.c     |    1 +
src/backend/storage/file/fd.c           |    1 +
src/backend/storage/ipc/procarray.c     |    3 +-
src/backend/storage/ipc/standby.c       |    1 +
src/backend/storage/lmgr/lock.c         |    1 +
src/backend/storage/lmgr/predicate.c    |    1 +
src/backend/tcop/utility.c              |    1 +
src/backend/utils/adt/txid.c            |    1 +
src/backend/utils/cache/relcache.c      |    1 +
src/backend/utils/cache/relmapper.c     |    2 +
src/backend/utils/init/postinit.c       |    1 +
src/backend/utils/sort/tuplestore.c     |    2 +
src/backend/utils/time/tqual.c          |    1 +
src/bin/pg_resetxlog/pg_resetxlog.c     |    1 +
src/include/access/clog.h               |    3 +-
src/include/access/gin.h                |    3 +-
src/include/access/gin_private.h        |    1 +
src/include/access/gist_private.h       |    1 +
src/include/access/hash.h               |    3 +-
src/include/access/heapam_xlog.h        |    4 +-
src/include/access/multixact.h          |    3 +-
src/include/access/nbtree.h             |    5 +-
src/include/access/spgist.h             |    3 +-
src/include/access/spgist_private.h     |    1 +
src/include/access/xact.h               |    4 +-
src/include/access/xlog.h               |  112 +----
src/include/access/xlog_internal.h      |   38 +-
src/include/access/xloginsert.h         |   66 +++
src/include/access/xlogrecord.h         |  100 ++++
src/include/access/xlogutils.h          |    8 +-
src/include/catalog/storage_xlog.h      |    3 +-
src/include/commands/dbcommands.h       |    3 +-
src/include/commands/sequence.h         |    3 +-
src/include/commands/tablespace.h       |    3 +-
src/include/replication/decode.h        |    1 +
src/include/storage/standby.h           |    3 +-
src/include/utils/relmapper.h           |    3 +-
84 files changed, 1123 insertions(+), 856 deletions(-)