Redesign cloud printing subsystem layer.

chrome/service/cloud_print/print_system_cups.cc

Index: chrome/service/cloud_print/print_system_cups.cc
===================================================================
--- chrome/service/cloud_print/print_system_cups.cc	(revision 48641)
+++ chrome/service/cloud_print/print_system_cups.cc	(working copy)
@@ -2,7 +2,7 @@
 // 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/printer_info.h"
+#include "chrome/service/cloud_print/print_system.h"
 
 #include <cups/cups.h>
 #include <list>
@@ -25,7 +25,107 @@
 static const char kCUPSPrinterInfoOpt[] = "printer-info";
 static const char kCUPSPrinterStateOpt[] = "printer-state";
 
-void EnumeratePrinters(PrinterList* printer_list) {
+class PrintSystemCUPS : public PrintSystem {
+ public:
+  virtual void EnumeratePrinters(PrinterList* printer_list);
+
+  virtual bool GetPrinterCapsAndDefaults(const std::string& printer_name,
+                                         PrinterCapsAndDefaults* printer_info);
+
+  virtual bool ValidatePrintTicket(const std::string& printer_name,
+                                   const std::string& print_ticket_data);
+
+  virtual bool 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,
+                             PlatformJobId* job_id_ret);
+
+  virtual bool GetJobDetails(const std::string& printer_name,
+                             PlatformJobId job_id,
+                             PrintJobDetails *job_details);
+
+  virtual bool IsValidPrinter(const std::string& printer_name);
+
+  // TODO(gene): Add implementation for CUPS print server watcher.
+  class PrintServerWatcherCUPS
+    : public PrintSystem::PrintServerWatcher {
+   public:
+    PrintServerWatcherCUPS() {}
+
+    // PrintSystem::PrintServerWatcher interface
+    virtual bool StartWatching(
+        PrintSystem::PrintServerWatcher::Delegate* delegate) {
+      NOTIMPLEMENTED();
+      return true;
+    }
+    virtual bool StopWatching() {
+      NOTIMPLEMENTED();
+      return true;
+    }
+  };
+
+  class PrinterWatcherCUPS
+      : public PrintSystem::PrinterWatcher {
+   public:
+     explicit PrinterWatcherCUPS(PrintSystemCUPS* print_system,
+                                 const std::string& printer_name)
+         : printer_name_(printer_name), print_system_(print_system) {
+     }
+
+    // PrintSystem::PrinterWatcher interface
+    virtual bool StartWatching(
+        PrintSystem::PrinterWatcher::Delegate* delegate) {
+      if (delegate_ != NULL)
+        StopWatching();
+      delegate_ = delegate;
+      MessageLoop::current()->PostDelayedTask(FROM_HERE,
+          NewRunnableMethod(this,
+              &PrintSystemCUPS::PrinterWatcherCUPS::Update), 5000);
+      return true;
+    }
+    virtual bool StopWatching() {
+      delegate_ = NULL;
+      return true;
+    }
+    bool GetCurrentPrinterInfo(PrinterBasicInfo* printer_info) {
+      DCHECK(printer_info);
+      return print_system_->GetPrinterInfo(printer_name_, printer_info);
+    }
+
+    void Update() {
+      if (delegate_ == NULL)
+        return;  // Orphan call. We have been stopped already.
+      // For CUPS proxy, we are going to fire OnJobChanged notification
+      // periodically. Higher level will check if there are any outstanding
+      // jobs for this printer and check their status. If printer has no
+      // outstanding jobs, OnJobChanged() will do nothing.
+      delegate_->OnJobChanged();
+      MessageLoop::current()->PostDelayedTask(FROM_HERE,
+          NewRunnableMethod(this,
+              &PrintSystemCUPS::PrinterWatcherCUPS::Update),
+          kNotificationTimeout);
+    }
+   private:
+    static const int kNotificationTimeout = 5000;  // in ms
+    std::string printer_name_;
+    PrintSystem::PrinterWatcher::Delegate* delegate_;
+    scoped_refptr<PrintSystemCUPS> print_system_;
+    DISALLOW_COPY_AND_ASSIGN(PrinterWatcherCUPS);
+  };
+
+  virtual PrintSystem::PrintServerWatcher* CreatePrintServerWatcher();
+  virtual PrintSystem::PrinterWatcher* CreatePrinterWatcher(
+      const std::string& printer_name);
+
+  // Helper functions.
+  bool GetPrinterInfo(const std::string& printer_name, PrinterBasicInfo* info);
+  bool ParsePrintTicket(const std::string& print_ticket,
+                        std::map<std::string, std::string>* options);
+};
+
+void PrintSystemCUPS::EnumeratePrinters(PrinterList* printer_list) {
   DCHECK(printer_list);
   printer_list->clear();
 
@@ -59,22 +159,31 @@
 
   cupsFreeDests(num_dests, destinations);
 
-  DLOG(INFO) << "Enumerated " << printer_list->size() << " printers.";
+  DLOG(INFO) << "CP_CUPS: Enumerated " << printer_list->size() << " printers.";
 }
 
-bool GetPrinterCapsAndDefaults(const std::string& printer_name,
-                               PrinterCapsAndDefaults* printer_info) {
+bool PrintSystemCUPS::GetPrinterCapsAndDefaults(const std::string& printer_name,
+                                         PrinterCapsAndDefaults* printer_info) {
   DCHECK(printer_info);
 
-  DLOG(INFO) << "Getting Caps and Defaults for:  " << printer_name;
+  DLOG(INFO) << "CP_CUPS: Getting Caps and Defaults for: " << printer_name;
 
   static Lock ppd_lock;
   // cupsGetPPD returns a filename stored in a static buffer in CUPS.
   // Protect this code with lock.
   ppd_lock.Acquire();
-  FilePath ppd_path(cupsGetPPD(printer_name.c_str()));
+  FilePath ppd_path;
+  const char* ppd_file_path = cupsGetPPD(printer_name.c_str());
+  if (ppd_file_path)
+    ppd_path = FilePath(ppd_file_path);
   ppd_lock.Release();
 
+  // In some cases CUPS failed to get ppd file.
+  if (ppd_path.empty()) {
+    DLOG(ERROR) << "CP_CUPS: Failed to get PPD for: " << printer_name;
+    return false;
+  }
+
   std::string content;
   bool res = file_util::ReadFileToString(ppd_path, &content);
 
@@ -91,25 +200,16 @@
   return res;
 }
 
-bool ValidatePrintTicket(const std::string& printer_name,
-                         const std::string& print_ticket_data) {
+bool PrintSystemCUPS::ValidatePrintTicket(const std::string& printer_name,
+                                        const std::string& print_ticket_data) {
   scoped_ptr<Value> ticket_value(base::JSONReader::Read(print_ticket_data,
       false));
   return ticket_value != NULL && ticket_value->IsType(Value::TYPE_DICTIONARY);
 }
 
-std::string GenerateProxyId() {
-  // TODO(gene): This code should generate a unique id for proxy. ID should be
-  // unique for this user. Rand may return the same number. We'll need to change
-  // this in the future.
-  std::string id("CP_PROXY_");
-  id += Uint64ToString(base::RandUint64());
-  return id;
-}
-
 // Print ticket on linux is a JSON string containing only one dictionary.
-bool ParsePrintTicket(const std::string& print_ticket,
-                      std::map<std::string, std::string>* options) {
+bool PrintSystemCUPS::ParsePrintTicket(const std::string& print_ticket,
+                                  std::map<std::string, std::string>* options) {
   DCHECK(options);
   scoped_ptr<Value> ticket_value(base::JSONReader::Read(print_ticket, false));
   if (ticket_value == NULL || !ticket_value->IsType(Value::TYPE_DICTIONARY))
@@ -130,15 +230,15 @@
   return true;
 }
 
-bool 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,
-                   PlatformJobId* job_id_ret) {
+bool 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,
+                                    PlatformJobId* job_id_ret) {
   DCHECK(job_id_ret);
 
-  DLOG(INFO) << "Spooling print job for: " << printer_name;
+  DLOG(INFO) << "CP_CUPS: Spooling print job for: " << printer_name;
 
   // We need to store options as char* string for the duration of the
   // cupsPrintFile call. We'll use map here to store options, since
@@ -162,6 +262,8 @@
                              cups_options.size(),
                              &(cups_options[0]));
 
+  DLOG(INFO) << "CP_CUPS: Job spooled, id: " << job_id;
+
   if (job_id == 0)
     return false;
 
@@ -169,12 +271,12 @@
   return true;
 }
 
-bool GetJobDetails(const std::string& printer_name,
-                   PlatformJobId job_id,
-                   PrintJobDetails *job_details) {
+bool PrintSystemCUPS::GetJobDetails(const std::string& printer_name,
+                                    PlatformJobId job_id,
+                                    PrintJobDetails *job_details) {
   DCHECK(job_details);
 
-  DLOG(INFO) << "Getting job details for: " << printer_name <<
+  DLOG(INFO) << "CP_CUPS: Getting job details for: " << printer_name <<
       " job_id: " << job_id;
 
   cups_job_t* jobs = NULL;
@@ -212,10 +314,11 @@
   return found;
 }
 
-bool GetPrinterInfo(const std::string& printer_name, PrinterBasicInfo* info) {
+bool PrintSystemCUPS::GetPrinterInfo(const std::string& printer_name,
+                                     PrinterBasicInfo* info) {
   DCHECK(info);
 
-  DLOG(INFO) << "Getting printer info for: " << printer_name;
+  DLOG(INFO) << "CP_CUPS: Getting printer info for: " << printer_name;
 
   // This is not very efficient way to get specific printer info. CUPS 1.4
   // supports cupsGetNamedDest() function. However, CUPS 1.4 is not available
@@ -233,99 +336,34 @@
   return false;
 }
 
-bool IsValidPrinter(const std::string& printer_name) {
+bool PrintSystemCUPS::IsValidPrinter(const std::string& printer_name) {
   PrinterBasicInfo info;
   return GetPrinterInfo(printer_name, &info);
 }
 
-class PrinterChangeNotifier::NotificationState
-    : public base::RefCountedThreadSafe<
-        PrinterChangeNotifier::NotificationState> {
- public:
-  NotificationState() : delegate_(NULL) {}
-  bool Start(const std::string& printer_name,
-             PrinterChangeNotifier::Delegate* delegate) {
-    if (delegate_ != NULL)
-      Stop();
-
-    printer_name_ = printer_name;
-    delegate_ = delegate;
-
-    MessageLoop::current()->PostDelayedTask(FROM_HERE,
-        NewRunnableMethod(this,
-            &PrinterChangeNotifier::NotificationState::Update), 5000);
-    return true;
-  }
-  bool Stop() {
-    delegate_ = NULL;
-    return true;
-  }
-  void Update() {
-    if (delegate_ == NULL)
-      return;  // Orphan call. We have been stopped already.
-    // For CUPS proxy, we are going to fire OnJobChanged notification
-    // periodically. Higher level will check if there are any outstanding
-    // jobs for this printer and check their status. If printer has no
-    // outstanding jobs, OnJobChanged() will do nothing.
-    delegate_->OnJobChanged();
-    MessageLoop::current()->PostDelayedTask(FROM_HERE,
-        NewRunnableMethod(this,
-            &PrinterChangeNotifier::NotificationState::Update),
-        kNotificationTimeout);
-  }
-  std::string printer_name() const {
-    return printer_name_;
-  }
- private:
-  friend class base::RefCountedThreadSafe<
-      PrinterChangeNotifier::NotificationState>;
-  ~NotificationState() {
-    Stop();
-  }
-  static const int kNotificationTimeout = 5000;  // in ms
-  std::string printer_name_;  // The printer being watched
-  PrinterChangeNotifier::Delegate* delegate_;  // Delegate to notify
-};
-
-PrinterChangeNotifier::PrinterChangeNotifier() : state_(NULL) {
+PrintSystem::PrintServerWatcher*
+PrintSystemCUPS::CreatePrintServerWatcher() {
+  return new PrintServerWatcherCUPS();
 }
 
-PrinterChangeNotifier::~PrinterChangeNotifier() {
-  StopWatching();
+PrintSystem::PrinterWatcher* PrintSystemCUPS::CreatePrinterWatcher(
+    const std::string& printer_name) {
+  DCHECK(!printer_name.empty());
+  return new PrinterWatcherCUPS(this, printer_name);
 }
 
-bool PrinterChangeNotifier::StartWatching(const std::string& printer_name,
-                                          Delegate* delegate) {
-  if (state_) {
-    NOTREACHED();
-    return false;
-  }
-  state_ = new NotificationState;
-  state_->AddRef();
-  if (!state_->Start(printer_name, delegate)) {
-    StopWatching();
-    return false;
-  }
-  return true;
+std::string PrintSystem::GenerateProxyId() {
+  // TODO(gene): This code should generate a unique id for proxy. ID should be
+  // unique for this user. Rand may return the same number. We'll need to change
+  // this in the future.
+  std::string id("CP_PROXY_");
+  id += Uint64ToString(base::RandUint64());
+  return id;
 }
 
-bool PrinterChangeNotifier::StopWatching() {
-  if (!state_) {
-    return false;
-  }
-  state_->Stop();
-  state_->Release();
-  state_ = NULL;
-  return true;
+scoped_refptr<PrintSystem> PrintSystem::CreateInstance() {
+  return new PrintSystemCUPS;
 }
 
-bool PrinterChangeNotifier::GetCurrentPrinterInfo(
-    PrinterBasicInfo* printer_info) {
-  if (!state_) {
-    return false;
-  }
-  DCHECK(printer_info);
-  return GetPrinterInfo(state_->printer_name(), printer_info);
-}
 }  // namespace cloud_print