Making CUPS calls non-blocking....

chrome/service/cloud_print/print_system_cups.cc

 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/service/cloud_print/print_system.h"
 
 #include <cups/cups.h>
 #include <dlfcn.h>
 #include <errno.h>
 #include <pthread.h>
@@ skipping 604 matching lines @@
   return new PrintSystemCUPS(print_system_settings);
 }
 
 int PrintSystemCUPS::PrintFile(const GURL& url, const char* name,
                                const char* filename, const char* title,
                                int num_options, cups_option_t* options) {
   if (url.is_empty()) {  // Use default (local) print server.
     return cupsPrintFile(name, filename, title, num_options, options);
   } else {
     printing::HttpConnectionCUPS http(url);
+    http.SetBlocking(false);
     return cupsPrintFile2(http.http(), name, filename,
                           title, num_options, options);
   }
 }
 
 int PrintSystemCUPS::GetJobs(cups_job_t** jobs, const GURL& url,
                              const char* name, int myjobs, int whichjobs) {
   if (url.is_empty()) {  // Use default (local) print server.
     return cupsGetJobs(jobs, name, myjobs, whichjobs);
   } else {
     printing::HttpConnectionCUPS http(url);
+    http.SetBlocking(false);
     return cupsGetJobs2(http.http(), jobs, name, myjobs, whichjobs);
   }
 }
 
 PlatformJobId PrintSystemCUPS::SpoolPrintJob(
     const std::string& print_ticket,
     const FilePath& print_data_file_path,
     const std::string& print_data_mime_type,
     const std::string& printer_name,
     const std::string& job_title,
@@ skipping 80 matching lines @@
       *short_printer_name = full_printer_name.substr(separator + 1);
       return &(*it);
     }
   }
 
   LOG(WARNING) << "Server not found for printer: " << full_printer_name;
   return NULL;
 }
 
 }  // namespace cloud_print