Implement Cdm::listStoredLicenses()

[ Merge of http://go/wvgerrit/23600 ]

This adds a new entry to IStorage:: -

  bool list(std::vector<std::string> file_names)

It returns the name of each file in the (origin-specific) file system.

b/34628115

Uses the current file system (origin-specific) bound to the CDM. Returns
the list of stored licenses (key_set_ids) in vector output parameter.

Test: verified by unittests on angler.

Change-Id: I988556b27c2a4b75f52b59bcd78cfeaddd649acd

libwvdrmengine/cdm/core/include/cdm_engine.h

@@ -4,6 +4,7 @@
 #define WVCDM_CORE_CDM_ENGINE_H_
 
 #include <string>
+#include <vector>
 
 #include "certificate_provisioning.h"
 #include "clock.h"
@@ -128,19 +129,29 @@ class CdmEngine {
   virtual CdmResponseType QueryOemCryptoSessionId(
       const CdmSessionId& session_id, CdmQueryMap* query_response);
 
-  // Provisioning related methods
+  // Generate and return a valid provisioning request.
   virtual CdmResponseType GetProvisioningRequest(
       CdmCertificateType cert_type, const std::string& cert_authority,
       CdmProvisioningRequest* request, std::string* default_url);
 
+  // Verify and process a provisioning response.
   virtual CdmResponseType HandleProvisioningResponse(
       const CdmProvisioningResponse& response, std::string* cert,
       std::string* wrapped_key);
 
+  // Return true if there is a device certificate on the current
+  // (origin-specific) file system.
   virtual bool IsProvisioned(CdmSecurityLevel security_level);
 
+  // Remove DRM certificate from the current (origin-specific)
+  // file system. This will force the device to reprovision itself.
   virtual CdmResponseType Unprovision(CdmSecurityLevel security_level);
 
+  // Return the list of key_set_ids stored on the current (origin-specific)
+  // file system.
+  virtual CdmResponseType ListStoredLicenses(
+      CdmSecurityLevel security_level, std::vector<std::string>* key_set_ids);
+
   // Usage related methods for streaming licenses
   // Retrieve a random usage info from the list of all usage infos for this app
   // id.

libwvdrmengine/cdm/core/include/cdm_session.h

@@ -5,6 +5,7 @@
 
 #include <set>
 #include <string>
+#include <vector>
 
 #include "crypto_session.h"
 #include "device_files.h"
@@ -119,6 +120,7 @@ class CdmSession {
   // release the underlying crypto session) rather than call this method.
   virtual CdmResponseType ReleaseCrypto();
 
+  // Delete current license and matching usage record
   bool DeleteLicense();
 
   // Generate unique ID for each new session.

libwvdrmengine/cdm/core/include/device_files.h

@@ -7,6 +7,7 @@
 
 #include <set>
 #include <string>
+#include <vector>
 
 #include "device_files.pb.h"
 #include "scoped_ptr.h"
@@ -78,6 +79,7 @@ class DeviceFiles {
       int64_t* grace_period_end_time, CdmAppParameterMap* app_parameters,
       std::string* usage_entry);
   virtual bool DeleteLicense(const std::string& key_set_id);
+  virtual bool ListLicenses(std::vector<std::string>* key_set_ids);
   virtual bool DeleteAllFiles();
   virtual bool DeleteAllLicenses();
   virtual bool LicenseExists(const std::string& key_set_id);
@@ -143,6 +145,7 @@ class DeviceFiles {
   bool RetrieveHashedFile(const std::string& name,
                           video_widevine_client::sdk::File* file);
   bool FileExists(const std::string& name);
+  bool ListFiles(std::vector<std::string>* names);
   bool RemoveFile(const std::string& name);
   ssize_t GetFileSize(const std::string& name);
 

libwvdrmengine/cdm/core/include/file_store.h

@@ -55,6 +55,11 @@ class FileSystem {
   virtual bool Remove(const std::string& file_path);
   virtual ssize_t FileSize(const std::string& file_path);
 
+  // Return the filenames stored at dir_path.
+  // dir_path will be stripped from the returned names.
+  virtual bool List(const std::string& dir_path,
+                    std::vector<std::string>* names);
+
   const std::string& origin() const { return origin_; }
   void SetOrigin(const std::string& origin);
 

libwvdrmengine/cdm/core/include/wv_cdm_types.h

@@ -271,6 +271,9 @@ enum CdmResponseType {
   SHRINK_USAGE_TABLER_HEADER_UNKNOWN_ERROR,
   MOVE_USAGE_ENTRY_UNKNOWN_ERROR,
   COPY_OLD_USAGE_ENTRY_UNKNOWN_ERROR,
+  INVALID_PARAMETERS_ENG_22,
+  STORE_LICENSE_ERROR_4, /* 235 */
+  LIST_LICENSES_ERROR,
 };
 
 enum CdmKeyStatus {