8.1beta, Subtle bug in COPY in Solaris systems

Hello, 

First, I'll show the warnings seen when compiling postgres on 
SunOS 5.6 with gcc 3.2.1

copy.c: In function `GetDecimalFromHex':
copy.c:2660: warning: subscript has type `char'
copy.c: In function `CopyReadAttributesText':
copy.c:2805: warning: subscript has type `char'
copy.c:2813: warning: subscript has type `char'

Actually this warnings are caused by the isdigit function.
On Solaris systems, isdigit is organized as an array lookup, so all the 
arguments should be casted to unsigned char. 

2660c2660
<       if (isdigit(hex))
---
>       if (isdigit((unsigned char)hex))
2805c2805
<                                                       if (isxdigit(hexchar))
---
>                                                       if (isxdigit((unsigned char)hexchar))
2813c2813
<                                                                       if (isxdigit(hexchar))
---
>                                                                       if (isxdigit((unsigned char)hexchar))



Actually that problem cause not only warnings but real bugs too,
exploiting that problem. (when the char >128 and is not casted to 
unsigned, on  solaris there will be a negative indices of arrays)

For example on SunOS (or any Solaris):

test=# CREATE TABLE test0 (xx char(2));
CREATE TABLE
test=# copy test0 from stdin;
Enter data to be copied followed by a newline.
End with a backslash and a period on a line by itself.
>> \x3п
>> \.
test=# select length(xx) from test0;length 
--------     1
(1 row)


But on NOT Solaris: 

test=# CREATE TABLE test0 (xx char(2));
CREATE TABLE
test=# copy test0 from stdin;
Enter data to be copied followed by a newline.
End with a backslash and a period on a line by itself.
>> \x3п
>> \.
test=# select length(xx) from test0;length 
--------     2
(1 row)


I'm not sure that everybody will see that code properly due to encoding 
differences. But the idea is just feed postgres with "\x3" and one 
character with the code >128. 



Regards,Sergey

*****************************************************
Sergey E. Koposov
Max-Planck Institut fuer Astronomie
Web: http://lnfm1.sai.msu.ru/~math 
E-mail: math@sai.msu.ru