cpp: Use gpgme_op_decrypt_ex and add new flags.

* lang/cpp/src/context.cpp: New decrypt and decryptVerify functions
that take flags as arguments. Use new variants in old functions.
(Context::setDecryptionFlags): New helper.
(Context::Private::Private): Initialize new member.
* lang/cpp/src/context_p.h (Context::Private::decryptFlags): New.
* lang/cpp/src/context.h (Context::DecryptFlags): New enum.
(Context::EncryptionFlags): Extend for EncryptWrap.

--
The setDecryptionFlags provides a generic way to set decryption
flags for the whole context. This allows existing code to just
keep using the old functions and modify the decryption behavior
in a central place.

lang/cpp/src/context.cpp

@@ -280,6 +280,11 @@ std::unique_ptr<Context> Context::createForEngine(Engine eng, Error *error)
     return std::unique_ptr<Context>(new Context(ctx));
 }
 
+void Context::setDecryptionFlags(DecryptionFlags flags)
+{
+    d->decryptFlags = flags;
+}
+
 //
 //
 // Context::Private
@@ -294,7 +299,8 @@ Context::Private::Private(gpgme_ctx_t c)
       lastAssuanInquireData(Data::null),
       lastAssuanTransaction(),
       lastEditInteractor(),
-      lastCardEditInteractor()
+      lastCardEditInteractor(),
+      decryptFlags(DecryptNone)
 {
 
 }
@@ -904,21 +910,32 @@ std::unique_ptr<AssuanTransaction> Context::takeLastAssuanTransaction()
     return std::move(d->lastAssuanTransaction);
 }
 
-DecryptionResult Context::decrypt(const Data &cipherText, Data &plainText)
+DecryptionResult Context::decrypt(const Data &cipherText, Data &plainText, const DecryptionFlags flags)
 {
     d->lastop = Private::Decrypt;
     const Data::Private *const cdp = cipherText.impl();
     Data::Private *const pdp = plainText.impl();
-    d->lasterr = gpgme_op_decrypt(d->ctx, cdp ? cdp->data : 0, pdp ? pdp->data : 0);
+    d->lasterr = gpgme_op_decrypt_ext(d->ctx, static_cast<gpgme_decrypt_flags_t> (d->decryptFlags), cdp ? cdp->data : 0, pdp ? pdp->data : 0);
     return DecryptionResult(d->ctx, Error(d->lasterr));
 }
 
+DecryptionResult Context::decrypt(const Data &cipherText, Data &plainText)
+{
+    return decrypt(cipherText, plainText, DecryptNone);
+}
+
+Error Context::startDecryption(const Data &cipherText, Data &plainText, const DecryptionFlags flags)
+{
+    d->lastop = Private::Decrypt;
+    const Data::Private *const cdp = cipherText.impl();
+    Data::Private *const pdp = plainText.impl();
+    return Error(d->lasterr = gpgme_op_decrypt_ext_start(d->ctx, static_cast<gpgme_decrypt_flags_t> (d->decryptFlags),
+                 cdp ? cdp->data : 0, pdp ? pdp->data : 0));
+}
+
 Error Context::startDecryption(const Data &cipherText, Data &plainText)
 {
-    d->lastop = Private::Decrypt;
+    return startDecryption(cipherText, plainText, DecryptNone);
-    const Data::Private *const cdp = cipherText.impl();
-    Data::Private *const pdp = plainText.impl();
-    return Error(d->lasterr = gpgme_op_decrypt_start(d->ctx, cdp ? cdp->data : 0, pdp ? pdp->data : 0));
 }
 
 DecryptionResult Context::decryptionResult() const
@@ -973,22 +990,33 @@ VerificationResult Context::verificationResult() const
     }
 }
 
-std::pair<DecryptionResult, VerificationResult> Context::decryptAndVerify(const Data &cipherText, Data &plainText)
+std::pair<DecryptionResult, VerificationResult> Context::decryptAndVerify(const Data &cipherText, Data &plainText, DecryptionFlags flags)
 {
     d->lastop = Private::DecryptAndVerify;
     const Data::Private *const cdp = cipherText.impl();
     Data::Private *const pdp = plainText.impl();
-    d->lasterr = gpgme_op_decrypt_verify(d->ctx, cdp ? cdp->data : 0, pdp ? pdp->data : 0);
+    d->lasterr = gpgme_op_decrypt_ext(d->ctx, static_cast<gpgme_decrypt_flags_t> (d->decryptFlags | DecryptVerify),
+                                      cdp ? cdp->data : 0, pdp ? pdp->data : 0);
     return std::make_pair(DecryptionResult(d->ctx, Error(d->lasterr)),
                           VerificationResult(d->ctx, Error(d->lasterr)));
 }
 
-Error Context::startCombinedDecryptionAndVerification(const Data &cipherText, Data &plainText)
+std::pair<DecryptionResult, VerificationResult> Context::decryptAndVerify(const Data &cipherText, Data &plainText)
+{
+    return decryptAndVerify(cipherText, plainText, DecryptNone);
+}
+
+Error Context::startCombinedDecryptionAndVerification(const Data &cipherText, Data &plainText, DecryptionFlags flags)
 {
     d->lastop = Private::DecryptAndVerify;
     const Data::Private *const cdp = cipherText.impl();
     Data::Private *const pdp = plainText.impl();
-    return Error(d->lasterr = gpgme_op_decrypt_verify_start(d->ctx, cdp ? cdp->data : 0, pdp ? pdp->data : 0));
+    return Error(d->lasterr = gpgme_op_decrypt_ext_start(d->ctx, static_cast<gpgme_decrypt_flags_t> (d->decryptFlags | DecryptVerify), cdp ? cdp->data : 0, pdp ? pdp->data : 0));
+}
+
+Error Context::startCombinedDecryptionAndVerification(const Data &cipherText, Data &plainText)
+{
+    return startCombinedDecryptionAndVerification(cipherText, plainText, DecryptNone);
 }
 
 unsigned int to_auditlog_flags(unsigned int flags)

lang/cpp/src/context.h

@@ -261,14 +261,28 @@ public:
     //
     // Crypto Operations
     //
-    //
+
+    enum DecryptionFlags {
+        // Keep in line with core's flags
+        DecryptNone = 0,
+        DecryptVerify = 1,
+        DecryptUnwrap = 128,
+        DecryptMaxValue = 0x80000000
+    };
 
     //
     // Decryption
     //
 
+    // Alternative way to set decryption flags as they were added only in
+    // 1.9.0 and so other API can still be used but with 1.9.0 additionally
+    // flags can be set.
+    void setDecryptionFlags (const DecryptionFlags flags);
+
     DecryptionResult decrypt(const Data &cipherText, Data &plainText);
     GpgME::Error startDecryption(const Data &cipherText, Data &plainText);
+    DecryptionResult decrypt(const Data &cipherText, Data &plainText, const DecryptionFlags flags);
+    GpgME::Error startDecryption(const Data &cipherText, Data &plainText, const DecryptionFlags flags);
     DecryptionResult decryptionResult() const;
 
     //
@@ -286,7 +300,9 @@ public:
     //
 
     std::pair<DecryptionResult, VerificationResult> decryptAndVerify(const Data &cipherText, Data &plainText);
+    std::pair<DecryptionResult, VerificationResult> decryptAndVerify(const Data &cipherText, Data &plainText, const DecryptionFlags flags);
     GpgME::Error startCombinedDecryptionAndVerification(const Data &cipherText, Data &plainText);
+    GpgME::Error startCombinedDecryptionAndVerification(const Data &cipherText, Data &plainText, const DecryptionFlags flags);
     // use verificationResult() and decryptionResult() to retrieve the result objects...
 
     //
@@ -325,7 +341,9 @@ public:
         Prepare = 4,
         ExpectSign = 8,
         NoCompress = 16,
-        Symmetric = 32
+        Symmetric = 32,
+        ThrowKeyIds = 64,
+        EncryptWrap = 128
     };
     EncryptionResult encrypt(const std::vector<Key> &recipients, const Data &plainText, Data &cipherText, EncryptionFlags flags);
     GpgME::Error encryptSymmetrically(const Data &plainText, Data &cipherText);

lang/cpp/src/context_p.h

@@ -77,6 +77,7 @@ public:
     Data lastAssuanInquireData;
     std::unique_ptr<AssuanTransaction> lastAssuanTransaction;
     std::unique_ptr<EditInteractor> lastEditInteractor, lastCardEditInteractor;
+    DecryptionFlags decryptFlags;
 };
 
 } // namespace GpgME