Create a new print backend for the updated CUPS APIs

printing/backend/cups_printer.h

+// Copyright 2016 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.
+
+#ifndef PRINTING_BACKEND_CUPS_PRINTER_H_
+#define PRINTING_BACKEND_CUPS_PRINTER_H_
+
+#include <cups/cups.h>
+
+#include <memory>
+#include <string>
+#include <vector>
+
+#include "base/memory/weak_ptr.h"
+#include "printing/printing_export.h"
+#include "url/gurl.h"
+
+namespace base {
+class FilePath;
+}
+
+namespace printing {
+
+struct PrinterBasicInfo;
+
+class DestinationDeleter {

[Lei Zhang, 2016/07/13 01:08:42]

Could some of these be shared for use with print_backend_cups.cc? They seem
generally useful for any CUPS code that have to deal with these structures.

[skau, 2016/07/14 20:43:06]

I've moved them to a separate file.  It's probably useful as we convert to smart
pointers.

+ public:
+  void operator()(cups_dest_t* dest) const;
+};
+
+class DestInfoDeleter {
+ public:
+  void operator()(cups_dinfo_t* info) const;
+};
+
+// Represents a CUPS printer.
+// Retrieves information from CUPS printer objects as requested.
+class PRINTING_EXPORT CupsPrinter {
+ public:
+  // This object now owns |dest| and |info|.
+  explicit CupsPrinter(base::WeakPtr<http_t> http,

[Lei Zhang, 2016/07/13 01:08:42]

Not explicit.

[skau, 2016/07/14 20:43:06]

Done.

+                       cups_dest_t* dest,
+                       cups_dinfo_t* info);
+
+  CupsPrinter(CupsPrinter&& printer);
+
+  ~CupsPrinter();
+
+  // Returns true if this is the default printer
+  bool is_default() const;
+
+  // Returns the supported ipp attributes for the given |option_name|.
+  // ipp_attribute_t* is owned by CupsPrinter.
+  ipp_attribute_t* GetSupportedOptionValues(
+      base::StringPiece option_name) const;
+
+  // Returns supported attribute values for |option_name| where the value can be
+  // convered to a string.
+  std::vector<base::StringPiece> GetSupportedOptionValueStrings(
+      base::StringPiece option_name) const;
+
+  // Returns the default ipp attributes for the given |option_name|.
+  // ipp_attribute_t* is owned by CupsPrinter.
+  ipp_attribute_t* GetDefaultOptionValue(base::StringPiece option_name) const;
+
+  bool CheckOptionSupported(base::StringPiece name,
+                            base::StringPiece value) const;
+
+  // Returns the file name for the PPD retrieved from the print server.
+  base::FilePath GetPPD() const;
+
+  // Returns the name of the printer as configured in CUPS
+  const std::string GetName() const;
+
+  const std::string GetMakeAndModel() const;
+
+  // Returns true if the printer is currently reachable and working.
+  bool IsAvailable() const;
+
+  // Populates |basic_info| with the relevant information about the printer
+  bool ToPrinterInfo(PrinterBasicInfo* basic_info) const;
+
+  ipp_status_t CreateJob(int* job_id,
+                         base::StringPiece job_title,
+                         const std::vector<cups_option_t>& options);
+
+  bool StartDocument(int job_id,
+                     base::StringPiece document_name,
+                     bool last_doc,
+                     const std::vector<cups_option_t>& options);
+
+  bool StreamData(char* buffer, int len);

[Lei Zhang, 2016/07/13 01:32:04]

Can this take a const std::vector<char>&  - use STL containers as long as
possible.

[skau, 2016/07/14 20:43:06]

Done.

+
+  bool FinishDocument();
+
+  ipp_status_t CloseJob(int job_id);
+
+ private:
+  bool InitializeDestInfo() const;
+
+  base::WeakPtr<http_t> cups_http_;
+  std::unique_ptr<cups_dest_t, DestinationDeleter> destination_;
+  mutable std::unique_ptr<cups_dinfo_t, DestInfoDeleter> dest_info_;
+
+  DISALLOW_COPY_AND_ASSIGN(CupsPrinter);
+};
+
+}  // namespace printing
+
+#endif  // PRINTING_BACKEND_CUPS_PRINTER_H_