#72 ecs_OpenDynamicLib fails on 64 bit Windows

[csd]

The problem is in the ecs_OpenDynamicLib function (in ecs_dyna.c) within the #ifdef _WINDOWS block. The check for failed load looks like this:

if ((int) handle <= (int) HINSTANCE_ERROR) {
    // ... Handle LoadLibrary failure
}

On 64 bit Windows, LoadModule returns a 64 bit value, but int is 32 bit. Casting to (signed) int drops the high 32 bits. The low 32 bits, interpreted as an int can be negative, causing OGDI to think the load failed.

From reading the MSDN docs for LoadModule, it would seem that the correct check should be like this:

if (handle == NULL) {
    // ... Handle LoadLibrary failure
}

[Even Rouault]

Fixed in
Checking in ogdi/c-api/ecs_dyna.c;
/cvsroot/ogdi/devdir/ogdi/c-api/ecs_dyna.c,v <-- ecs_dyna.c
new revision: 1.6; previous revision: 1.5