Seems this one got lost along the way somewhere. At least, I didn't get it
back... Trying a resend.

//Magnus

>  -----Original Message-----
> From:         Magnus Hagander  
> Sent: den 20 januari 2001 14:29
> To:   '[EMAIL PROTECTED]'
> Subject:      Postgresql on win32
> 
> Hello!
> 
> Here is a patch to make the current snapshot compile on Win32 
> (native, libpq and psql) again. Changes are:
> 1) psql requires the includes of "io.h" and "fcntl.h" in 
> command.c in order to make a call to open() work (io.h for 
> _open(), fcntl.h for the O_xxx)
> 2) PG_VERSION is no longer defined in version.h[.in], but in 
> configure.in. Since we don't do configure on native win32, we 
> need to put it in config.h.win32 :-(
> 3) Added define of SYSCONFDIR to config.h.win32 - libpq won't 
> compile without it. This functionality is *NOT* tested - it's 
> just defined as "" for now. May work, may not.
> 4) DEF_PGPORT renamed to DEF_PGPORT_STR
> 
> I have done the "basic tests" on it - it connects to a 
> database, and I can run queries. Haven't tested any of the 
> fancier functions (yet).
> 
> However, I stepped on a much bigger problem when fixing psql 
> to work. It no longer works when linked against the .DLL 
> version of libpq (which the Makefile does for it). I have 
> left it linked against this version anyway, pending the 
> comments I get on this mail :-)
> The problem is that there are strings being allocated from 
> libpq.dll using PQExpBuffers (for example, initPQExpBuffer() 
> on line 92 of input.c). These are being allocated using the 
> malloc function used by libpq.dll. This function *may* be 
> different from the malloc function used by psql.exe - only 
> the resulting pointer must be valid. And with the default 
> linking methods, it *WILL* be different. Later, psql.exe 
> tries to free() this string, at which point it crashes 
> because the free() function can't find the allocated block 
> (it's on the allocated blocks list used by the runtime lib of 
> libpq.dll).
> 
> Shouldn't the right thing to do be to have psql call 
> termPQExpBuffer() on the data instead? As it is now, 
> gets_fromFile() will just return the pointer received from 
> the PQExpBuffer.data (this may well be present at several 
> places - this is the one I was bitten by so far). Isn't that 
> kind of "accessing the internals of the PQExpBuffer 
> structure" wrong? Instead, perhaps it shuold make a copy of 
> the string, adn then termPQExpBuffer() it? In that case, the 
> string will have been allocated from within the same library 
> as the free() is called.
> 
> I can get it to work just fine by doing this - changing from 
> (around line 100 of input.c):
>                 if (buffer.data[buffer.len - 1] == '\n')
>                 {
>                         buffer.data[buffer.len - 1] = '\0';
>                         return buffer.data;
>                 }
> to
>               if (buffer.data[buffer.len - 1] == '\n')
>               {
>                       char *tmps;
>                       buffer.data[buffer.len - 1] = '\0';
>                       tmps = strdup(buffer.data);
>                       termPQExpBuffer(&buffer);
>                       return tmps;
>               }
> 
> and the same a bit further down in the same function.
> 
> But, as I said above, this may be at more places in the code? 
> Perhaps someone more familiar to it could comment on that?
> 
> 
> What do you think shuld be done about this? Personally, I go 
> by the "If you allocate a piece of memory using an interface, 
> use the same interface to free it", but the question is how 
> to make it work :-)
> 
> 
> Also, AFAIK this only affects psql.exe, so the changes made 
> to the libpq files by this patch are required no matter how 
> the other issue is handled.
> 
> Regards,
>  Magnus
> 
> 
>  <<pgsql-win32.patch>> 

pgsql-win32.patch

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