//-----------------------------------------------------------------------------
/// InitCommunication
///
/// This function only needs to be called by wrapper plugins. It sets up the
/// inter-process communication between the wrapper (which is in the app's
/// process space) and the PerfServer.
//-----------------------------------------------------------------------------
bool InitCommunication(const char* strShortDescription, ProcessRequest_type pProcessRequestCallback)
{
unsigned long pid = osGetCurrentProcessId();
#ifdef _WIN32
sprintf_s(g_strSharedMemoryName, PS_MAX_PATH, "%lu/%s", pid, strShortDescription);
#else
// the '/' character can't be used as a filename in Linux, so just use the plugin name as the shared memory name
// (ignore the process ID)
sprintf_s(g_strSharedMemoryName, PS_MAX_PATH, "%lu %s", pid, strShortDescription);
#endif
if (smCreate(g_strSharedMemoryName, 100, sizeof(HTTPRequestHeader)) == false)
{
Log(logERROR, "InitCommunication: Can't open or create SharedMemory for %s.\n", strShortDescription);
return false;
}
if (smOpen("PLUGINS_TO_GPS") == false)
{
smClose(g_strSharedMemoryName);
Log(logERROR, "InitCommunication: Can't open SharedMemory for PLUGINS_TO_GPS.\n");
return false;
}
// store a local pointer to the ProcessRequest function
g_processRequest = pProcessRequestCallback;
if (g_processRequest == NULL)
{
smClose(g_strSharedMemoryName);
Log(logERROR, "InitCommunication: ProcessRequest is NULL\n");
return false;
}
// protect the maps from being changed by other threads using the mutex
ScopeLock lock(s_mutex);
g_requestMap.clear();
g_pBufferedResponse = NULL;
g_uBufferedResponseSize = 0;
return true;
}
//--------------------------------------------------------------
/// Create the shared memory needed to communicate between the
/// web server and the plugin
/// \return true if successful, false if error
//--------------------------------------------------------------
bool ProcessTracker::CreateSharedMemory()
{
#ifdef _WIN32
if (smExists("GPS_TO_MDLL"))
{
if (smOpen("GPS_TO_MDLL"))
{
if (smLockGet("GPS_TO_MDLL"))
{
//the shared memory already exists, so we need to read everything from it, to make sure it's empty
// closing and recreated the shared memory does not work because the MicroDLL has it open
// so that it can inject into any spawned processes (via CreateProcess). If MicroDLL doesn't keep
// a handle to the shared memory, it could be closed by everyone, get destroyed and then it wouldn't
// be able to follow CreateProcess.
char tmp[ PS_MAX_PATH ];
while (smGet("GPS_TO_MDLL", NULL, 0) != 0)
{
// the smGet call will clear the shared memory
smGet("GPS_TO_MDLL", tmp, PS_MAX_PATH);
}
smUnlockGet("GPS_TO_MDLL");
}
}
}
// now write the plugin info into the shared memory
// Put wrapper info into a shared memory for micro DLL
// make the shared memory big enough for all the wrappers that are known about
// even though we're only going to write in the wrappers that are allowed
if (smCreate("GPS_TO_MDLL", (unsigned long)GetWrapperMap().size() * 3, PS_MAX_PATH))
{
// lock the buffer if it has enough space for 3 strings for each of the allowed wrappers
unsigned long ulNumBuffers = (unsigned long) g_allowedWrappersMap.size() * 3;
if (smLockPut("GPS_TO_MDLL", ulNumBuffers * PS_MAX_PATH, ulNumBuffers))
{
char strPath[PS_MAX_PATH];
char strName[PS_MAX_PATH];
char strDlls[PS_MAX_PATH];
for (WrapperMap::const_iterator iter = g_allowedWrappersMap.begin();
iter != g_allowedWrappersMap.end();
++iter)
{
strcpy_s(strPath, PS_MAX_PATH, iter->second.strPluginPath.asCharArray());
strcpy_s(strName, PS_MAX_PATH, iter->second.strPluginName.asCharArray());
strcpy_s(strDlls, PS_MAX_PATH, iter->second.strWrappedDll.asCharArray());
if (smPut("GPS_TO_MDLL", (void*) strPath, PS_MAX_PATH) == false ||
smPut("GPS_TO_MDLL", (void*) strName, PS_MAX_PATH) == false ||
smPut("GPS_TO_MDLL", (void*) strDlls, PS_MAX_PATH) == false)
{
Log(logERROR, "Couldn't put wrapper info into shared memory.\n");
smUnlockPut("GPS_TO_MDLL");
return false;
}
}
smUnlockPut("GPS_TO_MDLL");
}
else
{
Log(logERROR, "There is not enough space in the shared memory for the desired content.\n");
return false;
}
}
else
{
Log(logERROR, "Couldn't create shared memory to pass wrapper registration\n");
return false;
}
#else
for (WrapperMap::const_iterator iter = g_allowedWrappersMap.begin();
iter != g_allowedWrappersMap.end();
++iter)
{
// On Linux, Create the shared memory from the PerfStudio server so that
// it is cleaned up properly.
if (smCreate(iter->second.strPluginShortDesc.asCharArray(), 100, sizeof(HTTPRequestHeader)) == false)
{
Log(logERROR, "Couldn't create shared memory for plugin.\n");
return false;
}
}
#endif // def _WIN32
return true;
}
