postgresql/src/port
Tom Lane 00cdd83521 Adopt the GNU convention for handling tar-archive members exceeding 8GB.
The POSIX standard for tar headers requires archive member sizes to be
printed in octal with at most 11 digits, limiting the representable file
size to 8GB.  However, GNU tar and apparently most other modern tars
support a convention in which oversized values can be stored in base-256,
allowing any practical file to be a tar member.  Adopt this convention
to remove two limitations:
* pg_dump with -Ft output format failed if the contents of any one table
exceeded 8GB.
* pg_basebackup failed if the data directory contained any file exceeding
8GB.  (This would be a fatal problem for installations configured with a
table segment size of 8GB or more, and it has also been seen to fail when
large core dump files exist in the data directory.)

File sizes under 8GB are still printed in octal, so that no compatibility
issues are created except in cases that would have failed entirely before.

In addition, this patch fixes several bugs in the same area:

* In 9.3 and later, we'd defined tarCreateHeader's file-size argument as
size_t, which meant that on 32-bit machines it would write a corrupt tar
header for file sizes between 4GB and 8GB, even though no error was raised.
This broke both "pg_dump -Ft" and pg_basebackup for such cases.

* pg_restore from a tar archive would fail on tables of size between 4GB
and 8GB, on machines where either "size_t" or "unsigned long" is 32 bits.
This happened even with an archive file not affected by the previous bug.

* pg_basebackup would fail if there were files of size between 4GB and 8GB,
even on 64-bit machines.

* In 9.3 and later, "pg_basebackup -Ft" failed entirely, for any file size,
on 64-bit big-endian machines.

In view of these potential data-loss bugs, back-patch to all supported
branches, even though removal of the documented 8GB limit might otherwise
be considered a new feature rather than a bug fix.
2015-11-21 20:21:31 -05:00
..
.gitignore Convert cvsignore to gitignore, and add .gitignore for build targets. 2010-09-22 12:57:04 +02:00
Makefile Revert error-throwing wrappers for the printf family of functions. 2015-05-19 18:19:38 -04:00
README Remove cvs keywords from all files. 2010-09-20 22:08:53 +02:00
chklocale.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
crypt.c Suppress dead, unportable src/port/crypt.c code. 2014-10-12 23:27:06 -04:00
dirent.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
dirmod.c Use FLEXIBLE_ARRAY_MEMBER in Windows-specific code. 2015-02-21 16:49:35 -05:00
erand48.c Redesign tablesample method API, and do extensive code review. 2015-07-25 14:39:00 -04:00
fls.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
fseeko.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
getaddrinfo.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
getopt.c pgindent run for 9.4 2014-05-06 12:12:18 -04:00
getopt_long.c Add support for optional_argument to our own getopt_long() implementation. 2014-09-10 17:21:50 +02:00
getpeereid.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
getrusage.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
gettimeofday.c pgindent run for 9.5 2015-05-23 21:35:49 -04:00
inet_aton.c pgindent run for 9.4 2014-05-06 12:12:18 -04:00
inet_net_ntop.c Pgindent run before 9.1 beta2. 2011-06-09 14:32:50 -04:00
isinf.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
kill.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
mkdtemp.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
noblock.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
open.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
path.c Fix libpq's behavior when /etc/passwd isn't readable. 2015-01-11 12:35:44 -05:00
pg_crc32c_choose.c pgindent run for 9.5 2015-05-23 21:35:49 -04:00
pg_crc32c_sb8.c Reorganize our CRC source files again. 2015-04-14 17:03:42 +03:00
pg_crc32c_sse42.c pgindent run for 9.5 2015-05-23 21:35:49 -04:00
pgcheckdir.c Improve pg_check_dir code and comments. 2015-02-17 10:19:30 -05:00
pgmkdirp.c Fix various typos and grammar errors in comments. 2015-04-26 18:42:31 +02:00
pgsleep.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
pgstrcasecmp.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
pqsignal.c Remove support for Unix systems without the POSIX signal APIs. 2015-08-31 12:56:10 -04:00
pthread-win32.h Remove cvs keywords from all files. 2010-09-20 22:08:53 +02:00
qsort.c Fix a low-probability crash in our qsort implementation. 2015-07-16 22:57:46 -04:00
qsort_arg.c Fix a low-probability crash in our qsort implementation. 2015-07-16 22:57:46 -04:00
quotes.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
random.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
rint.c Upgrade src/port/rint.c to be POSIX-compliant. 2015-03-25 15:54:18 -04:00
snprintf.c Revert error-throwing wrappers for the printf family of functions. 2015-05-19 18:19:38 -04:00
sprompt.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
srandom.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
strerror.c Remove cvs keywords from all files. 2010-09-20 22:08:53 +02:00
strlcat.c pgindent run for 9.4 2014-05-06 12:12:18 -04:00
strlcpy.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
system.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
tar.c Adopt the GNU convention for handling tar-archive members exceeding 8GB. 2015-11-21 20:21:31 -05:00
thread.c Remove configure test for nonstandard variants of getpwuid_r(). 2015-01-11 12:52:37 -05:00
unsetenv.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
win32.ico Revert binary change in copyright year adjustment. 2012-01-01 19:40:13 -05:00
win32env.c Update copyright for 2015 2015-01-06 11:43:47 -05:00
win32error.c Message improvements 2015-11-16 21:39:23 -05:00
win32setlocale.c pgindent run for 9.5 2015-05-23 21:35:49 -04:00
win32ver.rc Stamp HEAD as 9.6devel. 2015-06-30 14:01:15 -04:00

README

src/port/README

libpgport
=========

libpgport must have special behavior.  It supplies functions to both
libraries and applications.  However, there are two complexities:

1)  Libraries need to use object files that are compiled with exactly
the same flags as the library.  libpgport might not use the same flags,
so it is necessary to recompile the object files for individual
libraries.  This is done by removing -lpgport from the link line:

        # Need to recompile any libpgport object files
        LIBS := $(filter-out -lpgport, $(LIBS))

and adding infrastructure to recompile the object files:

        OBJS= execute.o typename.o descriptor.o data.o error.o prepare.o memory.o \
                connect.o misc.o path.o exec.o \
                $(filter snprintf.o, $(LIBOBJS))

The problem is that there is no testing of which object files need to be
added, but missing functions usually show up when linking user
applications.

2) For applications, we use -lpgport before -lpq, so the static files
from libpgport are linked first.  This avoids having applications
dependent on symbols that are _used_ by libpq, but not intended to be
exported by libpq.  libpq's libpgport usage changes over time, so such a
dependency is a problem.  Win32, Linux, and Darwin use an export list to
control the symbols exported by libpq.