HPM compatibility improvements

Improved compatibility, portability and standards conformance.

- Since it is not possible to portably and reliably re-use the core's
  symbols in plugins, symbols are no longer exported unless explicitly
  required, in the UNIX builds. This mimics the Windows behavior and
  adds HPM compatibility to OSes such as FreeBSD. Credits to Andrei Karas
  for making this possible.
- For convenience, it is no longer necessary to call GET_SYMBOL, since
  the plugin will automatically import all the available symbols when
  it's loaded, depending on the included headers.
- Plugins are now supposed to include the "common/hercules.h" header
  before including anything else.  Incluing common/HPMi.h,
  common/cbasetypes.h or conf/core.h is no longer necessary, as those
  are guaranteed to be automatically included by hercules.h.
- HPM API version bumped to 1.1.

Signed-off-by: Haru <haru@dotalux.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/src/map/trade.c b/src/map/trade.c
index 2f6e2a648..8af3ddf4a 100644
--- a/src/map/trade.c
+++ b/src/map/trade.c
@@ -25,6 +25,7 @@
 #include <string.h>
 
 struct trade_interface trade_s;
+struct trade_interface *trade;
 
 /*==========================================
  * Initiates a trade request.