msIOContext* msIO_pushStdoutToBufferAndGetOldContext()
{
msIOContextGroup *group = msIO_GetContextGroup();
msIOContext *old_context;
/* Backup current context */
old_context = (msIOContext*) msSmallMalloc(sizeof(msIOContext));
memcpy(old_context, &group->stdout_context, sizeof(msIOContext));
msIO_installStdoutToBuffer();
return old_context;
}
/**
* @details This is called by `MapservAsync` and runs in a different thread to
* that function. It performs the actual work of interacting with
* mapserver. The code is based on the logic found in the `mapserv` program but
* the output is instead buffered using the mapserver output buffering
* functionality: it can then be captured and passed back to the client.
*
* @param req The asynchronous libuv request.
*/
void Map::MapservWork(uv_work_t *req) {
/* No HandleScope! This is run in a separate thread: *No* contact
should be made with the Node/V8 world here. */
MapBaton *baton = static_cast<MapBaton*>(req->data);
mapservObj* mapserv = NULL;
bool reportError = false; // flag an error as worthy of reporting
if (msDebugInitFromEnv() != MS_SUCCESS) {
reportError = true;
goto handle_error;
}
mapserv = msAllocMapServObj();
msIO_installStdinFromBuffer(); // required to catch POSTS without data
msIO_installStdoutToBuffer(); // required to capture mapserver output
// load the CGI parameters from the environment object
mapserv->request->NumParams = wrap_loadParams(mapserv->request,
GetEnv,
const_cast<char *>(baton->body.c_str()),
baton->body.length(),
static_cast<void *>(&(baton->env)));
if( mapserv->request->NumParams == -1 ) {
// no errors are generated by default but messages are output instead
msSetError( MS_MISCERR, "No request parameters loaded",
"Map::MapservWork" );
reportError = true;
goto get_output;
}
// Copy the map into the mapservObj for this request
if(!LoadMap(mapserv, baton->map)) {
reportError = true;
goto get_output;
}
// Execute the request
if(msCGIDispatchRequest(mapserv) != MS_SUCCESS) {
reportError = true;
goto get_output;
}
get_output:
// Get the content type. If headers other than content-type need to be
// retrieved it may be best to use something along the lines of
// <https://github.com/joyent/http-parser>.
baton->content_type = msIO_stripStdoutBufferContentType();
msIO_stripStdoutBufferContentHeaders();
// Get the buffered output
baton->buffer = msIO_getStdoutBufferBytes();
handle_error:
// handle any unhandled errors
errorObj *error = msGetErrorObj();
if (error && error->code != MS_NOERR) {
// report the error if requested
if (reportError) {
baton->error = new MapserverError(error);
}
msResetErrorList(); // clear all handled errors
}
// clean up
msFreeMapServObj(mapserv);
msIO_resetHandlers();
msDebugCleanup();
return;
}
