Add a method to query IPP printers for attributes.

printing/backend/cups_jobs.h

Index: printing/backend/cups_jobs.h
diff --git a/printing/backend/cups_jobs.h b/printing/backend/cups_jobs.h
index b1ca693c82858288fdf01ebffc2f41eda426e141..42cb20ce946c52158777dcfe39579f1f742a18df 100644
--- a/printing/backend/cups_jobs.h
+++ b/printing/backend/cups_jobs.h
@@ -10,6 +10,7 @@
 #include <cups/cups.h>
 
 #include <string>
+#include <utility>
 #include <vector>
 
 #include "printing/printing_export.h"
@@ -110,6 +111,23 @@ struct PRINTING_EXPORT PrinterStatus {
   std::string message;
 };
 
+struct PRINTING_EXPORT PrinterInfo {
+  PrinterInfo();
+  PrinterInfo(const PrinterInfo& info);
+
+  ~PrinterInfo();
+
+  // printer-make-and-model
+  std::string make_and_model;
+
+  // ipp-versions-supported
+  // A collection of major, minor pairs.
+  std::vector<std::pair<int, int>> ipp_versions;
+
+  // Does ipp-features-supported contain 'ipp-everywhere'.
+  bool ipp_everywhere = false;
+};
+
 // Specifies classes of jobs.
 enum JobCompletionState {
   COMPLETED,  // only completed jobs
@@ -125,6 +143,13 @@ void ParseJobsResponse(ipp_t* response,
 // Attempts to extract a PrinterStatus object out of |response|.
 void ParsePrinterStatus(ipp_t* response, PrinterStatus* printer_status);
 
+// Queries the printer at |address| on |port| with a Get-Printer-Attributes
+// request to populate |printer_info|.  Returns false if the request failed.

[Carlson, 2017/05/25 19:04:36]

This is a long latency function with no callback, that should be noted in the
comment.

[skau, 2017/05/27 02:01:20]

I've added a file comment since it applies to all the functions.

+bool PRINTING_EXPORT GetPrinterInfo(const std::string& address,
+                                    const int port,
+                                    const std::string& resource,
+                                    PrinterInfo* printer_info);
+
 // Attempts to retrieve printer status using connection |http| for |printer_id|.
 // Returns true if succcssful and updates the fields in |printer_status| as
 // appropriate.  Returns false if the request failed.