MS Windows, mingw compatibility of recent snapshots

Dear Al,

enclosed you will find an improved patch of c_attach.cc for MS Windows 
with correct error message handling, now tested with the gnucap att and 
det commands.

Regards

Holger


/* MS Windows portability added to c_attach.cc
  * DLLs may be loaded with the following patch
  */
//testing=none
#ifdef _WIN32
#include <windows.h>
#undef min
#undef max
#else
#include <dlfcn.h>
#endif

#include "ap.h"
#include "c_comand.h"

#ifdef _WIN32
/*--------------------------------------------------------------------------*/
static std::map<const std::string, HINSTANCE> attach_list;
/*--------------------------------------------------------------------------*/
void CMD::attach(CS& cmd)
{
   int here = cmd.cursor();
   std::string s;
   cmd >> s;

   LPVOID lpMsgBuf;
   DWORD dw;
   // load dll by its filename s (including path with backslashes)
   HINSTANCE handle = LoadLibrary(s.c_str());
   if (handle) {
     attach_list[s] = handle;
   }else{
     // get the error code
     dw = GetLastError();
     // get the corresponding error message
     FormatMessage(
         FORMAT_MESSAGE_ALLOCATE_BUFFER |
         FORMAT_MESSAGE_FROM_SYSTEM |
         FORMAT_MESSAGE_IGNORE_INSERTS,
         NULL,
         dw,
         MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
         (LPTSTR) &lpMsgBuf,
         0, NULL );
     // send the error message
     cmd.warn(bERROR, here, (LPCTSTR)lpMsgBuf);
     // free the error message buffer
     LocalFree(lpMsgBuf);
   }
}
/*--------------------------------------------------------------------------*/
void CMD::detach(CS& cmd)
{
   int here = cmd.cursor();
   std::string s;
   cmd >> s;

   HINSTANCE handle = attach_list[s];
   if (handle) {
     FreeLibrary(handle);
     attach_list[s] = NULL;
   }else{
     cmd.warn(bERROR, here, "plugin not attached");
   }
}
#else
/*--------------------------------------------------------------------------*/
static std::map<const std::string, void*> attach_list;
/*--------------------------------------------------------------------------*/
void CMD::attach(CS& cmd)
{
   int here = cmd.cursor();
   std::string s;
   cmd >> s;

   void* handle = dlopen(s.c_str(), RTLD_NOW);
   if (handle) {
     attach_list[s] = handle;
   }else{
     cmd.warn(bERROR, here, dlerror());
   }
}
/*--------------------------------------------------------------------------*/
void CMD::detach(CS& cmd)
{
   int here = cmd.cursor();
   std::string s;
   cmd >> s;

   void* handle = attach_list[s];
   if (handle) {
     dlclose(handle);
     attach_list[s] = NULL;
   }else{
     cmd.warn(bERROR, here, "plugin not attached");
   }
}
#endif
/*--------------------------------------------------------------------------*/
/*--------------------------------------------------------------------------*/