Distinguish between C and SQL mode for C-style comments.

SQL standard asks for allowing nested comments, while C does not. Therefore the
two comments, while mostly similar, have to be parsed seperately.
Allow C array definitions to use sizeof().

When parsing C variable definitions ecpg should allow sizeof() operators as array dimensions.
Fix new and latent bugs with errno handling in secure_read/secure_write.

These functions must be careful that they return the intended value of
errno to their callers.  There were several scenarios where this might
not happen:

1. The recent SSL renegotiation patch added a hunk of code that would
execute after setting errno.  In the first place, it's doubtful that we
should consider renegotiation to be successfully completed after a failure,
and in the second, there's no real guarantee that the called OpenSSL
routines wouldn't clobber errno.  Fix by not executing that hunk except
during success exit.

2. errno was left in an unknown state in case of an unrecognized return
code from SSL_get_error().  While this is a "can't happen" case, it seems
like a good idea to be sure we know what would happen, so reset errno to
ECONNRESET in such cases.  (The corresponding code in libpq's fe-secure.c
already did this.)

3. There was an (undocumented) assumption that client_read_ended() wouldn't
change errno.  While true in the current state of the code, this seems less
than future-proof.  Add explicit saving/restoring of errno to make sure
that changes in the called functions won't break things.

I see no need to back-patch, since #1 is new code and the other two issues
are mostly hypothetical.

Per discussion with Amit Kapila.
Lessen library-loading log level.

Previously, messages were emitted at the LOG level every time a
backend preloaded a library. That was acceptable (though unnecessary)
for shared_preload_libraries; but it was excessive for
local_preload_libraries and session_preload_libraries. Reduce to
DEBUG1.

Also, there was logic in the EXEC_BACKEND case to avoid repeated
messages for shared_preload_libraries by demoting them to
DEBUG2. DEBUG1 seems more appropriate there, as well, so eliminate
that special case.

Peter Geoghegan.
Fix ecpg parsing of sizeof().

The last fix used the wrong non-terminal to define valid types.
More improvement to comment parsing in ecpg.

ECPG is not supposed to allow and output nested comments in C. These comments
are only allowed in the SQL parts and must not be written into the C file.
Also the different handling of different comments is documented.
Change SET LOCAL/CONSTRAINTS/TRANSACTION and ABORT behavior

Change SET LOCAL/CONSTRAINTS/TRANSACTION behavior outside of a
transaction block from error (post-9.3) to warning.  (Was nothing in <=
9.3.)  Also change ABORT outside of a transaction block from notice to
warning.
Add missing entry for session_preload_libraries in sample config.

The omission was apparently an oversight in the original patch.
Handle domains over arrays like plain arrays in PL/python.

Domains over arrays are now converted to/from python lists when passed as
arguments or return values. Like regular arrays.

This has some potential to break applications that rely on the old behavior
that they are passed as strings, but in practice there probably aren't many
such applications out there.

Rodolfo Campero
ECPG: Make the preprocessor emit ';' if the variable type for a list of
variables is varchar. This fixes this test case:

int main(void)
{
    exec sql begin declare section;
    varchar a[50], b[50];
    exec sql end declare section;

    return 0;
}

Since varchars are internally turned into custom structs and
the type name is emitted for these variable declarations,
the preprocessed code previously had:

struct varchar_1  { ... }  a _,_  struct varchar_2  { ... }  b ;

The comma in the generated C file was a syntax error.

There are no regression test changes since it's not exercised.

Patch by Boszormenyi Zoltan <zb@cybertec.at>
ECPG: Free the malloc()'ed variables in the test so it comes out clean on
Valgrind runs.

Patch by Boszormenyi Zoltan <zb@cybertec.at>
ECPG: Add EXEC SQL CLOSE C to the tests.

Patch by Boszormenyi Zoltan <zb@cybertec.at>
ECPG: Simplify free_variable()

Patch by Boszormenyi Zoltan <zb@cybertec.at>
ECPG: Fix offset to NULL/size indicator array.

Patch by Boszormenyi Zoltan <zb@cybertec.at>
Oops, forgot to "git add" last minute changes to regression test.
doc: Add id to index in XSLT build

That way, the HTML file name of the index will be the same as currently
for the DSSSL build.
Implement information_schema.parameters.parameter_default column

Reviewed-by: Ali Dar <ali.munir.dar@gmail.com>
Reviewed-by: Amit Khandekar <amit.khandekar@enterprisedb.com>
Reviewed-by: Rodolfo Campero <rodolfo.campero@anachronics.com>
Fix typo in release note.

Backpatch to 9.1.

Josh Kupershmidt
Add --xlogdir option to pg_basebackup, for specifying the pg_xlog directory.

Haribabu kommi, slightly modified by me.
ECPG: Fix searching for quoted cursor names case-sensitively.

Patch by Böszörményi Zoltán <zb@cybertec.at>