On Aug 19, 2010, at 2:35 PM, Tom Lane wrote:
> Steven Schlansker <ste...@trumpet.io> writes:
>> I'm having a rather annoying problem - a particular string is causing the
>> Postgres COPY functionality to lose a byte, causing data corruption in
>> backups and transferred data.
>
> I was able to reproduce this on my own Mac. Some tracing shows that the
> problem is that isspace(0x85) returns true when in locale en_US.utf-8.
> This causes array_in to drop the final byte of the array element string,
> thinking that it's insignificant whitespace.
The 0x85 seems to be the second byte of a multibyte UTF-8
sequence. I'm not at all experienced with character encodings so I could
be totally off base, but isn't it wrong to ever call isspace(0x85),
whatever the result may be, given that the actual character is 0xCF85?
(U+03C5, GREEK SMALL LETTER UPSILON)
> I believe that you must
> not have produced the data file data.copy on a Mac, or at least not in
> that locale setting, because array_out should have double-quoted the
> array element given that behavior of isspace().
Correct, it was produced on a Linux machine. That said, the charset
there was also UTF-8.
>
> Now, it's probably less than sane for isspace() to be behaving that way,
> since in a UTF8-based locale 0x85 can't be regarded as a valid character
> code at all. But I'm not hopeful about the results of filing a bug with
> Apple, because their UTF8-based locales have a lot of other bu^H^Hdubious
> behaviors too, which they appear not to care much about.
I actually can't reproduce that behavior here:
#include <ctype.h>
#include <stdio.h>
int main() {
printf("%d\n", isspace(0x85));
return 0;
}
[ste...@xxx:~]% gcc -o test test.c
[ste...@xxx:~]% ./test
0
[ste...@xxx:~]% locale
LANG="en_US.utf-8"
LC_COLLATE="en_US.utf-8"
LC_CTYPE="en_US.utf-8"
LC_MESSAGES="en_US.utf-8"
LC_MONETARY="en_US.utf-8"
LC_NUMERIC="en_US.utf-8"
LC_TIME="en_US.utf-8"
LC_ALL=
[ste...@xxx:~]% uname -a
Darwin xxx.local 10.4.0 Darwin Kernel Version 10.4.0: Fri Apr 23 18:28:53 PDT
2010; root:xnu-1504.7.4~1/RELEASE_I386 i386 i386
Thanks much for your help,
Steven Schlansker
--
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers
