/* module_info.cc

   Copyright 1999 Cygnus Solutions.

   Written by Egor Duda <deo@logos-m.ru>

This file is part of Cygwin.

This software is a copyrighted work licensed under the terms of the
Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
details. */

#include <stdlib.h>
#include <windows.h>
#include <psapi.h>

static int psapi_loaded = 0;
static HMODULE psapi_module_handle = NULL;

typedef BOOL WINAPI (tf_EnumProcessModules) (HANDLE, HMODULE *, DWORD,
					     LPDWORD);
typedef BOOL WINAPI (tf_GetModuleInformation) (HANDLE, HMODULE, LPMODULEINFO,
					       DWORD);
typedef DWORD WINAPI (tf_GetModuleFileNameExA) (HANDLE, HMODULE, LPSTR,
						DWORD);

static tf_EnumProcessModules *psapi_EnumProcessModules = NULL;
static tf_GetModuleInformation *psapi_GetModuleInformation = NULL;
static tf_GetModuleFileNameExA *psapi_GetModuleFileNameExA = NULL;

/* Returns full name of Dll, which is loaded by hProcess at BaseAddress.
   Uses psapi.dll. */

char *
psapi_get_module_name (HANDLE hProcess, DWORD BaseAddress)
{
  DWORD len;
  MODULEINFO mi;
  unsigned int i;
  HMODULE dh_buf[1];
  HMODULE *DllHandle = dh_buf;
  DWORD cbNeeded;
  BOOL ok;

  char name_buf[MAX_PATH + 1];

  if (!psapi_loaded ||
      psapi_EnumProcessModules == NULL ||
      psapi_GetModuleInformation == NULL ||
      psapi_GetModuleFileNameExA == NULL)
    {
      if (psapi_loaded)
	goto failed;
      psapi_loaded = 1;
      psapi_module_handle = LoadLibrary ("psapi.dll");
      if (!psapi_module_handle)
	goto failed;
      psapi_EnumProcessModules =
	(tf_EnumProcessModules *) GetProcAddress (psapi_module_handle,
						  "EnumProcessModules");
      psapi_GetModuleInformation =
	(tf_GetModuleInformation *) GetProcAddress (psapi_module_handle,
						    "GetModuleInformation");
      psapi_GetModuleFileNameExA =
	(tf_GetModuleFileNameExA *) GetProcAddress (psapi_module_handle,
						    "GetModuleFileNameExA");
      if (psapi_EnumProcessModules == NULL
	  || psapi_GetModuleInformation == NULL
	  || psapi_GetModuleFileNameExA == NULL)
	goto failed;
    }

  ok = (*psapi_EnumProcessModules) (hProcess,
				    DllHandle, sizeof (HMODULE), &cbNeeded);

  if (!ok || !cbNeeded)
    goto failed;
  DllHandle = (HMODULE *) malloc (cbNeeded);
  if (!DllHandle)
    goto failed;
  ok = (*psapi_EnumProcessModules) (hProcess, DllHandle, cbNeeded, &cbNeeded);
  if (!ok)
    {
      free (DllHandle);
      goto failed;
    }

  for (i = 0; i < cbNeeded / sizeof (HMODULE); i++)
    {
      if (!(*psapi_GetModuleInformation) (hProcess,
					  DllHandle[i], &mi, sizeof (mi)))
	{
	  free (DllHandle);
	  goto failed;
	}

      len = (*psapi_GetModuleFileNameExA) (hProcess,
					   DllHandle[i], name_buf, MAX_PATH);
      if (len == 0)
	{
	  free (DllHandle);
	  goto failed;
	}

      if ((DWORD) (mi.lpBaseOfDll) == BaseAddress)
	{
	  free (DllHandle);
	  return strdup (name_buf);
	}
    }

failed:
  return NULL;
}
