ui/display/util/x11/edid_parser_x11.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "ui/display/util/x11/edid_parser_x11.h"
   6
   7 #include <X11/extensions/Xrandr.h>
   8 #include <X11/Xatom.h>
   9 #include <X11/Xlib.h>
  10
  11 #include "base/strings/string_util.h"
  12 #include "ui/display/util/edid_parser.h"
  13 #include "ui/gfx/x/x11_types.h"
  14
  15 namespace ui {
  16
  17 namespace {
  18
  19 bool IsRandRAvailable() {
  20   int randr_version_major = 0;
  21   int randr_version_minor = 0;
  22   static bool is_randr_available = XRRQueryVersion(
  23       gfx::GetXDisplay(), &randr_version_major, &randr_version_minor);
  24   return is_randr_available;
  25 }
  26
  27 // Get the EDID data from the |output| and stores to |edid|.
  28 // Returns true if EDID property is successfully obtained. Otherwise returns
  29 // false and does not touch |edid|.
  30 bool GetEDIDProperty(XID output, std::vector<uint8_t>* edid) {
  31   if (!IsRandRAvailable())
  32     return false;
  33
  34   Display* display = gfx::GetXDisplay();
  35
  36   static Atom edid_property = XInternAtom(
  37       gfx::GetXDisplay(),
  38       RR_PROPERTY_RANDR_EDID, false);
  39
  40   bool has_edid_property = false;
  41   int num_properties = 0;
  42   gfx::XScopedPtr<Atom[]> properties(
  43       XRRListOutputProperties(display, output, &num_properties));
  44   for (int i = 0; i < num_properties; ++i) {
  45     if (properties[i] == edid_property) {
  46       has_edid_property = true;
  47       break;
  48     }
  49   }
  50   if (!has_edid_property)
  51     return false;
  52
  53   Atom actual_type;
  54   int actual_format;
  55   unsigned long bytes_after;
  56   unsigned long nitems = 0;
  57   unsigned char* prop = nullptr;
  58   XRRGetOutputProperty(display,
  59                        output,
  60                        edid_property,
  61                        0,                // offset
  62                        128,              // length
  63                        false,            // _delete
  64                        false,            // pending
  65                        AnyPropertyType,  // req_type
  66                        &actual_type,
  67                        &actual_format,
  68                        &nitems,
  69                        &bytes_after,
  70                        &prop);
  71   DCHECK_EQ(XA_INTEGER, actual_type);
  72   DCHECK_EQ(8, actual_format);
  73   edid->assign(prop, prop + nitems);
  74   XFree(prop);
  75   return true;
  76 }
  77
  78 // Gets some useful data from the specified output device, such like
  79 // manufacturer's ID, product code, and human readable name. Returns false if it
  80 // fails to get those data and doesn't touch manufacturer ID/product code/name.
  81 // nullptr can be passed for unwanted output parameters.
  82 bool GetOutputDeviceData(XID output,
  83                          uint16_t* manufacturer_id,
  84                          std::string* human_readable_name) {
  85   std::vector<uint8_t> edid;
  86   if (!GetEDIDProperty(output, &edid))
  87     return false;
  88
  89   return ParseOutputDeviceData(edid, manufacturer_id, nullptr,
  90                                human_readable_name, nullptr, nullptr);
  91 }
  92
  93 }  // namespace
  94
  95 bool GetDisplayId(XID output_id,
  96                   uint8_t output_index,
  97                   int64_t* display_id_out) {
  98   std::vector<uint8_t> edid;
  99   if (!GetEDIDProperty(output_id, &edid))
 100     return false;
 101
 102   bool result =
 103       GetDisplayIdFromEDID(edid, output_index, display_id_out, nullptr);
 104   return result;
 105 }
 106
 107 std::string GetDisplayName(RROutput output) {
 108   std::string display_name;
 109   GetOutputDeviceData(output, nullptr, &display_name);
 110   return display_name;
 111 }
 112
 113 bool GetOutputOverscanFlag(RROutput output, bool* flag) {
 114   std::vector<uint8_t> edid;
 115   if (!GetEDIDProperty(output, &edid))
 116     return false;
 117
 118   bool found = ParseOutputOverscanFlag(edid, flag);
 119   return found;
 120 }
 121
 122 }  // namespace ui