Revert of Reland 2:Geolocation: move from content/browser to device/

content/browser/geolocation/wifi_data_provider_corewlan_mac.mm

Index: content/browser/geolocation/wifi_data_provider_corewlan_mac.mm
diff --git a/content/browser/geolocation/wifi_data_provider_corewlan_mac.mm b/content/browser/geolocation/wifi_data_provider_corewlan_mac.mm
new file mode 100644
index 0000000000000000000000000000000000000000..89485d55bea2a85fd849f7601f2380e803d041e8
--- /dev/null
+++ b/content/browser/geolocation/wifi_data_provider_corewlan_mac.mm
@@ -0,0 +1,192 @@
+// Copyright (c) 2011 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.
+
+// Implements a WLAN API binding for CoreWLAN, as available on OSX 10.6
+
+#include "content/browser/geolocation/wifi_data_provider_mac.h"
+
+#include <dlfcn.h>
+#import <Foundation/Foundation.h>
+#include <stdint.h>
+
+#include "base/mac/scoped_nsautorelease_pool.h"
+#include "base/mac/scoped_nsobject.h"
+#include "base/macros.h"
+#include "base/metrics/histogram.h"
+#include "base/strings/sys_string_conversions.h"
+
+// Define a subset of the CoreWLAN interfaces we require. We can't depend on
+// CoreWLAN.h existing as we need to build on 10.5 SDKs. We can't just send
+// messages to an untyped id due to the build treating warnings as errors,
+// hence the reason we need class definitions.
+// TODO(joth): When we build all 10.6 code exclusively 10.6 SDK (or later)
+// tidy this up to use the framework directly. See http://crbug.com/37703
+
+@interface CWInterface : NSObject
++ (CWInterface*)interface;
++ (CWInterface*)interfaceWithName:(NSString*)name;
++ (NSArray*)supportedInterfaces;
+- (NSArray*)scanForNetworksWithParameters:(NSDictionary*)parameters
+                                    error:(NSError**)error;
+@end
+
+@interface CWNetwork : NSObject <NSCopying, NSCoding>
+@property (nonatomic, readonly) NSString* ssid;
+@property (nonatomic, readonly) NSString* bssid;
+@property (nonatomic, readonly) NSData* bssidData;
+@property (nonatomic, readonly) NSNumber* securityMode;
+@property (nonatomic, readonly) NSNumber* phyMode;
+@property (nonatomic, readonly) NSNumber* channel;
+@property (nonatomic, readonly) NSNumber* rssi;
+@property (nonatomic, readonly) NSInteger rssiValue;
+@property (nonatomic, readonly) NSNumber* noise;
+@property (nonatomic, readonly) NSData* ieData;
+@property (nonatomic, readonly) BOOL isIBSS;
+- (BOOL)isEqualToNetwork:(CWNetwork*)network;
+@end
+
+namespace content {
+
+class CoreWlanApi : public WifiDataProviderCommon::WlanApiInterface {
+ public:
+  CoreWlanApi() {}
+
+  // Must be called before any other interface method. Will return false if the
+  // CoreWLAN framework cannot be initialized (e.g. running on pre-10.6 OSX),
+  // in which case no other method may be called.
+  bool Init();
+
+  // WlanApiInterface
+  bool GetAccessPointData(WifiData::AccessPointDataSet* data) override;
+
+ private:
+  base::scoped_nsobject<NSBundle> bundle_;
+  base::scoped_nsobject<NSString> merge_key_;
+
+  DISALLOW_COPY_AND_ASSIGN(CoreWlanApi);
+};
+
+bool CoreWlanApi::Init() {
+  // As the WLAN api binding runs on its own thread, we need to provide our own
+  // auto release pool. It's simplest to do this as an automatic variable in
+  // each method that needs it, to ensure the scoping is correct and does not
+  // interfere with any other code using autorelease pools on the thread.
+  base::mac::ScopedNSAutoreleasePool auto_pool;
+  bundle_.reset([[NSBundle alloc]
+      initWithPath:@"/System/Library/Frameworks/CoreWLAN.framework"]);
+  if (!bundle_) {
+    DVLOG(1) << "Failed to load the CoreWLAN framework bundle";
+    return false;
+  }
+
+  // Dynamically look up the value of the kCWScanKeyMerge (i.e. without build
+  // time dependency on the 10.6 specific library).
+  void* dl_handle = dlopen([[bundle_ executablePath] fileSystemRepresentation],
+                           RTLD_LAZY | RTLD_LOCAL);
+  if (dl_handle) {
+    NSString* key = *reinterpret_cast<NSString**>(dlsym(dl_handle,
+                                                        "kCWScanKeyMerge"));
+    if (key)
+      merge_key_.reset([key copy]);
+  }
+  // "Leak" dl_handle rather than dlclose it, to ensure |merge_key_|
+  // remains valid.
+  if (!merge_key_) {
+    // Fall back to a known-working value should the lookup fail (if
+    // this value is itself wrong it's not the end of the world, we might just
+    // get very slightly lower quality location fixes due to SSID merges).
+    DLOG(WARNING) << "Could not dynamically load the CoreWLAN merge key";
+    merge_key_.reset([@"SCAN_MERGE" retain]);
+  }
+
+  return true;
+}
+
+bool CoreWlanApi::GetAccessPointData(WifiData::AccessPointDataSet* data) {
+  base::mac::ScopedNSAutoreleasePool auto_pool;
+  // Initialize the scan parameters with scan key merging disabled, so we get
+  // every AP listed in the scan without any SSID de-duping logic.
+  NSDictionary* params =
+      [NSDictionary dictionaryWithObject:[NSNumber numberWithBool:NO]
+                                  forKey:merge_key_.get()];
+
+  Class cw_interface_class = [bundle_ classNamed:@"CWInterface"];
+  NSArray* supported_interfaces = [cw_interface_class supportedInterfaces];
+  uint interface_error_count = 0;
+  for (NSString* interface_name in supported_interfaces) {
+    CWInterface* corewlan_interface =
+        [cw_interface_class interfaceWithName:interface_name];
+    if (!corewlan_interface) {
+      DLOG(WARNING) << interface_name << ": initWithName failed";
+      ++interface_error_count;
+      continue;
+    }
+
+    const base::TimeTicks start_time = base::TimeTicks::Now();
+
+    NSError* err = nil;
+    NSArray* scan = [corewlan_interface scanForNetworksWithParameters:params
+                                                                error:&err];
+    const int error_code = [err code];
+    const int count = [scan count];
+    // We could get an error code but count != 0 if the scan was interrupted,
+    // for example. For our purposes this is not fatal, so process as normal.
+    if (error_code && count == 0) {
+      DLOG(WARNING) << interface_name << ": CoreWLAN scan failed with error "
+                    << error_code;
+      ++interface_error_count;
+      continue;
+    }
+
+    const base::TimeDelta duration = base::TimeTicks::Now() - start_time;
+
+    UMA_HISTOGRAM_CUSTOM_TIMES(
+        "Net.Wifi.ScanLatency",
+        duration,
+        base::TimeDelta::FromMilliseconds(1),
+        base::TimeDelta::FromMinutes(1),
+        100);
+
+    DVLOG(1) << interface_name << ": found " << count << " wifi APs";
+
+    for (CWNetwork* network in scan) {
+      DCHECK(network);
+      AccessPointData access_point_data;
+      NSData* mac = [network bssidData];
+      DCHECK([mac length] == 6);
+      if (![mac bytes])
+        continue;  // crbug.com/545501
+      access_point_data.mac_address =
+          MacAddressAsString16(static_cast<const uint8_t*>([mac bytes]));
+      access_point_data.radio_signal_strength = [network rssiValue];
+      access_point_data.channel = [[network channel] intValue];
+      access_point_data.signal_to_noise =
+          access_point_data.radio_signal_strength - [[network noise] intValue];
+      access_point_data.ssid = base::SysNSStringToUTF16([network ssid]);
+      data->insert(access_point_data);
+    }
+  }
+
+  UMA_HISTOGRAM_CUSTOM_COUNTS(
+      "Net.Wifi.InterfaceCount",
+      [supported_interfaces count] - interface_error_count,
+      1,
+      5,
+      6);
+
+  // Return true even if some interfaces failed to scan, so long as at least
+  // one interface did not fail.
+  return interface_error_count == 0 ||
+         [supported_interfaces count] > interface_error_count;
+}
+
+WifiDataProviderCommon::WlanApiInterface* NewCoreWlanApi() {
+  std::unique_ptr<CoreWlanApi> self(new CoreWlanApi);
+  if (self->Init())
+    return self.release();
+
+  return NULL;
+}
+
+}  // namespace content