(1) Return a boolean instead of util::Status for methods in wv_cas_ecm.h

(2) Update wv_cas_ecm_example to NOT depend on ABSL

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=218884631

example/wv_cas_ecm_example.cc

@@ -8,47 +8,43 @@
 
 // Example of how to use the wv_cas_ecm library.
 
+#include <iostream>
 #include <string>
 
-#include "gflags/gflags.h"
-#include "glog/logging.h"
-#include "absl/strings/escaping.h"
-#include "absl/strings/str_cat.h"
-#include "util/status.h"
 #include "media_cas_packager_sdk/public/wv_cas_ecm.h"
 
+const int kContentIvSize = 16;
+const bool kKeyRotationEnabled = true;
+const int kCryptoMode = 1;                                          // CTR
 const char kEvenKey[] = "even_content_key";                         // 16 bytes
 const char kEvenContentIv8Bytes[] = "evencont";                     // 8 bytes
+const char kEvenContentIv16Bytes[] = "evencontevencont";            // 16 bytes
 const char kOddKey[] = "odd_content_key.";                          // 16 bytes
 const char kOddContentIv8Bytes[] = "oddcont.";                      // 8 bytes
+const char kOddContentIv16Bytes[] = "oddcont.oddcont.";             // 16 bytes
 const char kEntitlementKeyId[] = "ent_key_id......";                // 16 bytes
 const char kEntitlementKey[] = "entitlement_key.................";  // 32 bytes
 
 int main(int argc, char **argv) {
-  gflags::ParseCommandLineFlags(&argc, &argv, true);
-
   widevine::cas::WvCasEcm wv_cas_ecm;
-  auto status = wv_cas_ecm.Initialize(/* content_iv_size= */ 16,
+  bool status =
-                                      /* key_rotation_enabled= */ true,
+      wv_cas_ecm.Initialize(kContentIvSize, kKeyRotationEnabled, kCryptoMode);
-                                      /* crypto_mode= */ 1);
+  if (!status) {
-  if (!status.ok()) {
+    std::cerr << "Failed to initialize WV CAS ECM, error." << std::endl;
-    LOG(FATAL) << "Failed to initialize WV CAS ECM, error: " << status;
   }
   std::string ecm;
-  status = wv_cas_ecm.GenerateEcm(
+  status = wv_cas_ecm.GenerateEcm(kEvenKey, kEvenContentIv16Bytes, kOddKey,
-      /* even_key= */ kEvenKey,
+                                  kOddContentIv16Bytes, kEntitlementKeyId,
-      /* even_content_iv= */
+                                  kEntitlementKey, &ecm);
-      absl::StrCat(kEvenContentIv8Bytes, kEvenContentIv8Bytes),
+  if (!status) {
-      /* odd_key= */ kOddKey,
+    std::cerr << "Failed to generate WV CAS ECM, error" << std::endl;
-      /* odd_content_iv= */
-      absl::StrCat(kOddContentIv8Bytes, kOddContentIv8Bytes),
-      /* entitlement_key_id= */ kEntitlementKeyId,
-      /* entitlement_key= */ kEntitlementKey, &ecm);
-  if (!status.ok()) {
-    LOG(FATAL) << "Failed to generate WV CAS ECM, error: " << status;
   } else {
-    LOG(INFO) << "Generated WV CAS ECM (in hex): "
+    std::cout << "ECM size: " << ecm.size() << std::endl;
-              << absl::BytesToHexString(ecm);
+    std::cout << "ECM bytes: ";
+    for (size_t i = 0; i < ecm.size(); i++) {
+      printf("'\\x%x', ", static_cast<uint16_t>(ecm.at(i)));
+    }
+    std::cout << std::endl;
   }
 
   return 0;

media_cas_packager_sdk/public/wv_cas_ecm.h

@@ -47,12 +47,12 @@ class WvCasEcm {
   //   only CTR is supported by Widevine CAS plugin for now
   //
   // Returns:
-  // - A status indicating whether there was any error during initialization
+  // - A boolean indicating whether there was any error during initialization
   //
   // Note:
   // - 'even'/'odd' key in the ECM will be be encrypted using AEC_CBC
-  virtual util::Status Initialize(int content_iv_size,
+  virtual bool Initialize(int content_iv_size, bool key_rotation_enabled,
-                                  bool key_rotation_enabled, int crypto_mode);
+                          int crypto_mode);
 
   // Generate an ECM containing two keys (even and odd). Can be called when
   // |key_rotation_enabled| is initialized to 'true'.
@@ -67,20 +67,18 @@ class WvCasEcm {
   // - |ecm| for returning the generated ECM, must not be nullptr
   //
   // Returns:
-  // - A status indicating whether there was any error during processing
+  // - A boolean indicating whether there was any error during processing
   //
   // Note:
   // - The same |entitlement_key| will be used to encrypt both |even_key|
   //   and |odd_key| in the ECM
   // - Size of |even_content_iv| and |odd_content_iv| must match
   //   |content_iv_size| set during initialization
-  virtual util::Status GenerateEcm(const std::string& even_key,
+  virtual bool GenerateEcm(const std::string& even_key,
-                                   const std::string& even_content_iv,
+                           const std::string& even_content_iv, const std::string& odd_key,
-                                   const std::string& odd_key,
                            const std::string& odd_content_iv,
                            const std::string& entitlement_key_id,
-                                   const std::string& entitlement_key,
+                           const std::string& entitlement_key, std::string* ecm) const;
-                                   std::string* ecm) const;
 
   // Generate an ECM containing only a singe even key. Can be called when
   // |key_rotation_enabled| is initialized to 'false'.
@@ -93,12 +91,12 @@ class WvCasEcm {
   // - |ecm| for returning the generated ECM, must not be nullptr
   //
   // Returns:
-  // - A status indicating whether there was any error during processing
+  // - A boolean indicating whether there was any error during processing
   //
   // Note:
   // - Size of |even_content_iv| and |odd_content_iv| must match
   //   |content_iv_size| set during initialization
-  virtual util::Status GenerateSingleKeyEcm(const std::string& even_key,
+  virtual bool GenerateSingleKeyEcm(const std::string& even_key,
                                     const std::string& even_content_iv,
                                     const std::string& entitlement_key_id,
                                     const std::string& entitlement_key,