Driver optimization

Hello,
I used the psqlodbc driver and did a little profiling for the speed. It
turns out that the memory management is very slow, using malloc from the
crt.
I have found another implementation of malloc, at
http://gee.cs.oswego.edu/dl/html/malloc.html
source code at
ftp://g.oswego.edu/pub/misc/malloc.c

This version is in the public domain and could be included in the project.

The performance increase is dramatic.

If the changes are OK, please commit them to the official cvs

Just add the malloc.c to the project, define the symbols USE_DL_PREFIX
and USE_LOCKS=1 and add the following code to psqlodbc.h:

#ifdef USE_DL_PREFIX
void * __cdecl dlcalloc(size_t, size_t);
void __cdecl dlfree(void *);
void * __cdecl dlmalloc(size_t);
void * __cdecl dlrealloc(void *, size_t);
char * __cdecl dlstrdup (const char *);

#undef malloc
#undef realloc
#undef calloc
#undef free

#define malloc dlmalloc
#define realloc dlrealloc
#define calloc dlcalloc
#define free dlfree
#endif /* USE_DL_PREFIX */

Andrei Gaspar