Implement Chromium side of MediaKeys.isTypeSupported().

content/renderer/media/crypto/key_systems.cc

Index: content/renderer/media/crypto/key_systems.cc
diff --git a/content/renderer/media/crypto/key_systems.cc b/content/renderer/media/crypto/key_systems.cc
index a15e0b3578172be5e3ddcbaa4dc6e41a307ebf21..8acbf35060aaa0aefbda764a6a069fe43273eebb 100644
--- a/content/renderer/media/crypto/key_systems.cc
+++ b/content/renderer/media/crypto/key_systems.cc
@@ -14,6 +14,7 @@
 #include "base/time/time.h"
 #include "content/public/common/content_client.h"
 #include "content/public/common/eme_codec.h"
+#include "content/public/common/eme_init_data_type.h"
 #include "content/public/renderer/content_renderer_client.h"
 #include "content/public/renderer/key_system_info.h"
 #include "content/renderer/media/crypto/key_systems_support_uma.h"
@@ -35,6 +36,11 @@ struct CodecMask {
   EmeCodec mask;
 };
 
+struct InitDataTypeMask {

[ddorwin, 2014/09/13 01:20:45]

nit: move IDT stuff before container and codec to match ITS order.

[sandersd (OOO until July 31), 2014/09/22 23:45:53]

Done.

+  const char* type;
+  EmeInitDataType mask;

[ddorwin, 2014/09/13 01:20:45]

This seems like more of a type string to enum map.

I see that CodecMask is named this way, though. :(
Maybe we can replace "mask" with "enum" throughout.

[sandersd (OOO until July 31), 2014/09/22 23:45:52]

I had a go at renaming these, hopefully it's better.

+};
+
 // Mapping between container types and the masks of associated codecs.
 // Only audio codec can belong to a "audio/*" container. Both audio and video
 // codecs can belong to a "video/*" container.
@@ -61,6 +67,13 @@ CodecMask kCodecMasks[] = {
 #endif  // defined(USE_PROPRIETARY_CODECS)
 };
 
+// Mapping between initialization data types and their masks.

[ddorwin, 2014/09/13 01:20:45]

ditto on moving

[sandersd (OOO until July 31), 2014/09/22 23:45:53]

Done.

+InitDataTypeMask kInitDataTypeMasks[] = {
+    {"cenc", EME_INIT_DATA_TYPE_CENC},

[ddorwin, 2014/09/13 03:51:05]

This is a straight conversion and never depends on the key system. Should we
just do the conversion from JS string to usable value in WebCDMImpl.cc?

[sandersd (OOO until July 31), 2014/09/22 23:45:53]

We can, but then blink needs to know what the supported values are (and the enum
needs to move there), which seems wrong.

[ddorwin, 2014/09/23 22:48:15]

I think it's probably reasonable for Blink to know the possibly supported
values. If one is registered, it can be added to that interface. It's still up
to Chromium _whether_ it is supported.

+    {"webm", EME_INIT_DATA_TYPE_WEBM},
+    {"keyids", EME_INIT_DATA_TYPE_KEYIDS},
+};
+
 static void AddClearKey(std::vector<KeySystemInfo>* concrete_key_systems) {
   KeySystemInfo info(kClearKeyKeySystem);
 
@@ -80,6 +93,8 @@ static void AddClearKey(std::vector<KeySystemInfo>* concrete_key_systems) {
   info.supported_codecs |= EME_CODEC_MP4_ALL;
 #endif  // defined(USE_PROPRIETARY_CODECS)
 
+  info.supported_init_data_types = EME_INIT_DATA_TYPE_ALL;

[ddorwin, 2014/09/13 01:20:46]

ditto on moving (also in other files)

[sandersd (OOO until July 31), 2014/09/22 23:45:52]

Done.

+
   info.use_aes_decryptor = true;
 
   concrete_key_systems->push_back(info);
@@ -93,6 +108,12 @@ class KeySystems {
 
   bool IsConcreteSupportedKeySystem(const std::string& key_system);
 
+  bool IsSupportedKeySystem(const std::string& key_system);
+
+  bool IsSupportedKeySystemWithInitDataType(
+      const std::string& key_system,
+      const std::string& init_data_type);
+
   bool IsSupportedKeySystemWithMediaMimeType(
       const std::string& mime_type,
       const std::vector<std::string>& codecs,
@@ -120,6 +141,7 @@ class KeySystems {
       const std::string& pepper_type,
 #endif
       SupportedCodecs supported_codecs,
+      SupportedInitDataTypes supported_init_data_types,

[ddorwin, 2014/09/13 01:20:45]

nit: move up one line to match ITS order.

[sandersd (OOO until July 31), 2014/09/22 23:45:52]

Done.

       const std::string& parent_key_system);
 
   friend struct base::DefaultLazyInstanceTraits<KeySystems>;
@@ -133,12 +155,14 @@ class KeySystems {
     std::string pepper_type;
 #endif
     SupportedCodecs supported_codecs;
+    SupportedInitDataTypes supported_init_data_types;

[ddorwin, 2014/09/13 01:20:45]

ditto

[sandersd (OOO until July 31), 2014/09/22 23:45:52]

Done.

   };
 
   typedef base::hash_map<std::string, KeySystemProperties>
       KeySystemPropertiesMap;
   typedef base::hash_map<std::string, std::string> ParentKeySystemMap;
   typedef base::hash_map<std::string, EmeCodec> CodecMaskMap;
+  typedef base::hash_map<std::string, EmeInitDataType> InitDataTypeMaskMap;

[ddorwin, 2014/09/13 01:20:46]

ditto

[sandersd (OOO until July 31), 2014/09/22 23:45:53]

Done.

 
   KeySystems();
   ~KeySystems() {}
@@ -167,6 +191,7 @@ class KeySystems {
 
   CodecMaskMap container_codec_masks_;
   CodecMaskMap codec_masks_;
+  InitDataTypeMaskMap init_data_type_masks_;

[ddorwin, 2014/09/13 01:20:45]

ditto

[sandersd (OOO until July 31), 2014/09/22 23:45:53]

Done.

 
   bool needs_update_;
   base::Time last_update_time_;
@@ -189,18 +214,15 @@ KeySystems& KeySystems::GetInstance() {
 // the instance is lazily initiated.
 KeySystems::KeySystems() : needs_update_(true) {
   // Build container and codec masks for quick look up.
-  for (size_t i = 0; i < arraysize(kContainerCodecMasks); ++i) {
-    const CodecMask& container_codec_mask = kContainerCodecMasks[i];
-    DCHECK(container_codec_masks_.find(container_codec_mask.type) ==
-           container_codec_masks_.end());
-    container_codec_masks_[container_codec_mask.type] =
-        container_codec_mask.mask;
-  }
-  for (size_t i = 0; i < arraysize(kCodecMasks); ++i) {
-    const CodecMask& codec_mask = kCodecMasks[i];
-    DCHECK(codec_masks_.find(codec_mask.type) == codec_masks_.end());
-    codec_masks_[codec_mask.type] = codec_mask.mask;
+#define BUILD_MASK(dst, src)                      \

[ddorwin, 2014/09/13 01:20:45]

Macros aren't allowed. Would a template function work?

[sandersd (OOO until July 31), 2014/09/22 23:45:52]

I've expanded the macro, but I do think the macro version is harder to typo.

+  for (size_t i = 0; i < arraysize(src); ++i) {   \
+    DCHECK(dst.find(src[i].type) == dst.end()); \
+    dst[src[i].type] = src[i].mask;              \
   }
+  BUILD_MASK(container_codec_masks_, kContainerCodecMasks);
+  BUILD_MASK(codec_masks_, kCodecMasks);
+  BUILD_MASK(init_data_type_masks_, kInitDataTypeMasks);
+#undef BUILD_MASK
 
   UpdateSupportedKeySystems();
 
@@ -264,6 +286,7 @@ void KeySystems::AddConcreteSupportedKeySystems(
                                   key_system_info.pepper_type,
 #endif
                                   key_system_info.supported_codecs,
+                                  key_system_info.supported_init_data_types,
                                   key_system_info.parent_key_system);
   }
 }
@@ -275,6 +298,7 @@ void KeySystems::AddConcreteSupportedKeySystem(
     const std::string& pepper_type,
 #endif
     SupportedCodecs supported_codecs,
+    SupportedInitDataTypes supported_init_data_types,
     const std::string& parent_key_system) {
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK(!IsConcreteSupportedKeySystem(concrete_key_system))
@@ -291,6 +315,7 @@ void KeySystems::AddConcreteSupportedKeySystem(
 #endif
 
   properties.supported_codecs = supported_codecs;
+  properties.supported_init_data_types = supported_init_data_types;
 
   concrete_key_system_map_[concrete_key_system] = properties;
 
@@ -306,8 +331,7 @@ void KeySystems::AddConcreteSupportedKeySystem(
 
 bool KeySystems::IsConcreteSupportedKeySystem(const std::string& key_system) {
   DCHECK(thread_checker_.CalledOnValidThread());
-  return concrete_key_system_map_.find(key_system) !=
-      concrete_key_system_map_.end();
+  return concrete_key_system_map_.count(key_system);

[ddorwin, 2014/09/13 01:20:45]

Is there a reason you made this change? Not that it matters in practice, but his
requires iterating through the entire list even after one is found.

[sandersd (OOO until July 31), 2014/09/22 23:45:53]

It's a hash_map.

 }
 
 bool KeySystems::IsSupportedContainer(
@@ -369,6 +393,45 @@ bool KeySystems::IsSupportedContainerAndCodecs(
   return true;
 }
 
+bool KeySystems::IsSupportedKeySystem(const std::string& key_system) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  return (parent_key_system_map_.count(key_system) ||

[ddorwin, 2014/09/13 01:20:45]

ditto.

[sandersd (OOO until July 31), 2014/09/22 23:45:53]

Acknowledged.

+          concrete_key_system_map_.count(key_system));

[ddorwin, 2014/09/13 01:20:45]

minor: We're more likely to see concrete key system queries, so check that one
first.

[sandersd (OOO until July 31), 2014/09/22 23:45:53]

Done.

+}
+
+bool KeySystems::IsSupportedKeySystemWithInitDataType(
+    const std::string& key_system,
+    const std::string& init_data_type) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  // If |key_system| is a parent key system, use its concrete child.
+  std::string concrete_key_system = key_system;
+  ParentKeySystemMap::const_iterator parent_key_system_iter =
+      parent_key_system_map_.find(key_system);
+  if (parent_key_system_iter != parent_key_system_map_.end())
+    concrete_key_system = parent_key_system_iter->second;
+
+  // Locate |concrete_key_system|.
+  KeySystemPropertiesMap::const_iterator key_system_iter =
+      concrete_key_system_map_.find(concrete_key_system);
+  if (key_system_iter == concrete_key_system_map_.end())
+    return false;
+
+  // Check |init_data_type|.
+  InitDataTypeMaskMap::const_iterator init_data_type_iter =
+      init_data_type_masks_.find(init_data_type);
+  if (init_data_type_iter == init_data_type_masks_.end())
+    return false;
+
+  // Check |key_system| x |init_data_type|.
+  const KeySystemProperties& properties = key_system_iter->second;
+  const EmeInitDataType& init_data_type_mask = init_data_type_iter->second;
+  if (!(properties.supported_init_data_types & init_data_type_mask))
+    return false;
+
+  return true;
+}
+
 bool KeySystems::IsSupportedKeySystemWithMediaMimeType(
     const std::string& mime_type,
     const std::vector<std::string>& codecs,
@@ -488,6 +551,17 @@ bool IsConcreteSupportedKeySystem(const std::string& key_system) {
   return KeySystems::GetInstance().IsConcreteSupportedKeySystem(key_system);
 }
 
+bool IsSupportedKeySystem(const std::string& key_system) {
+  return KeySystems::GetInstance().IsSupportedKeySystem(key_system);
+}
+
+bool IsSupportedKeySystemWithInitDataType(
+    const std::string& key_system,
+    const std::string& init_data_type) {
+  return KeySystems::GetInstance().IsSupportedKeySystemWithInitDataType(
+      key_system, init_data_type);
+}
+
 bool IsSupportedKeySystemWithMediaMimeType(
     const std::string& mime_type,
     const std::vector<std::string>& codecs,