qt: Support reading signed/encrypted archives directly from a file

* lang/qt/src/decryptverifyarchivejob.cpp,
lang/qt/src/decryptverifyarchivejob.h (DecryptVerifyArchiveJob): Add
member functions setInputFile, inputFile.
* lang/qt/src/decryptverifyarchivejob_p.h
(DecryptVerifyArchiveJobPrivate): Add member m_inputFilePath.
* lang/qt/src/qgpgmedecryptverifyarchivejob.cpp (decrypt_verify): Move
creation of indata to decrypt_verify_from_io_device.
(decrypt_verify_from_io_device, decrypt_verify_from_file_name): New.
(QGpgMEDecryptVerifyArchiveJob::start): Use
decrypt_verify_from_io_device instead of decrypt_verify.
(QGpgMEDecryptVerifyArchiveJobPrivate::startIt): Start the job with the
values from member variables.

* lang/qt/tests/run-decryptverifyarchivejob.cpp (createInput): Remove.
(main): Remove creation of input. Make the job read the archive directly
from the given archive name.
--

This makes it possible to tell gpgtar to read the signed/encrypted
archive directly from a specified file bypassing GpgME's Data IO.

GnuPG-bug-id: 6530

6 files changed, 76 insertions, 38 deletions

diff --git a/NEWS b/NEWS
index 7712c7d9..790e646a 100644
--- a/NEWS
+++ b/NEWS
@@ -11,6 +11,9 @@ Noteworthy changes in version 1.21.0 (unreleased)
  * qt: Allow writing the created archives directly to a
    file.  [T6530]
 
+ * qt: Allow reading the signed/encrypted archive to decrypt
+   or verify directly from a file.  [T6530]
+
  * qt: Qt Jobs working with QIODeviceDataProvider now properly
    handle input-size hints and progress for files larger.
    2^32 bytes in 32 bit builds.  [T6534]
@@ -23,6 +26,8 @@ Noteworthy changes in version 1.21.0 (unreleased)
  cpp: Data::setFlag                         NEW.
  cpp: Data::setSizeHint                     NEW.
  qt: Job::startIt                           NEW.
+ qt: DecryptVerifyArchiveJob::setInputFile  NEW.
+ qt: DecryptVerifyArchiveJob::inputFile     NEW.
  qt: EncryptArchiveJob::setRecipients       NEW.
  qt: EncryptArchiveJob::recipients          NEW.
  qt: EncryptArchiveJob::setInputPaths       NEW.
diff --git a/lang/qt/src/decryptverifyarchivejob.cpp b/lang/qt/src/decryptverifyarchivejob.cpp
index ebfd36ca..76c1721a 100644
--- a/lang/qt/src/decryptverifyarchivejob.cpp
+++ b/lang/qt/src/decryptverifyarchivejob.cpp
@@ -56,6 +56,18 @@ bool DecryptVerifyArchiveJob::isSupported()
     return (gpgVersion >= "2.4.1") || (gpgVersion >= "2.2.42" && gpgVersion < "2.3.0");
 }
 
+void DecryptVerifyArchiveJob::setInputFile(const QString &path)
+{
+    auto d = jobPrivate<DecryptVerifyArchiveJobPrivate>(this);
+    d->m_inputFilePath = path;
+}
+
+QString DecryptVerifyArchiveJob::inputFile() const
+{
+    auto d = jobPrivate<DecryptVerifyArchiveJobPrivate>(this);
+    return d->m_inputFilePath;
+}
+
 void DecryptVerifyArchiveJob::setOutputDirectory(const QString &outputDirectory)
 {
     auto d = jobPrivate<DecryptVerifyArchiveJobPrivate>(this);
diff --git a/lang/qt/src/decryptverifyarchivejob.h b/lang/qt/src/decryptverifyarchivejob.h
index 4e72be2d..6d87dd36 100644
--- a/lang/qt/src/decryptverifyarchivejob.h
+++ b/lang/qt/src/decryptverifyarchivejob.h
@@ -63,6 +63,18 @@ public:
 
     static bool isSupported();
 
+    /**
+     * Sets the path of the file to read the archive from.
+     *
+     * Used if the job is started with startIt().
+     */
+    void setInputFile(const QString &path);
+    QString inputFile() const;
+
+    /**
+     * Sets the directory the content of the decrypted archive shall be
+     * written to.
+     */
     void setOutputDirectory(const QString &outputDirectory);
     QString outputDirectory() const;
 
diff --git a/lang/qt/src/decryptverifyarchivejob_p.h b/lang/qt/src/decryptverifyarchivejob_p.h
index b4e66530..e0823d23 100644
--- a/lang/qt/src/decryptverifyarchivejob_p.h
+++ b/lang/qt/src/decryptverifyarchivejob_p.h
@@ -41,6 +41,7 @@ namespace QGpgME
 
 struct DecryptVerifyArchiveJobPrivate : public JobPrivate
 {
+    QString m_inputFilePath;
     QString m_outputDirectory;
 };
 
diff --git a/lang/qt/src/qgpgmedecryptverifyarchivejob.cpp b/lang/qt/src/qgpgmedecryptverifyarchivejob.cpp
index 3fd58e35..98ca7403 100644
--- a/lang/qt/src/qgpgmedecryptverifyarchivejob.cpp
+++ b/lang/qt/src/qgpgmedecryptverifyarchivejob.cpp
@@ -43,6 +43,8 @@
 #include "dataprovider.h"
 #include "decryptverifyarchivejob_p.h"
 
+#include <QFile>
+
 #include <data.h>
 
 using namespace QGpgME;
@@ -64,11 +66,7 @@ public:
     ~QGpgMEDecryptVerifyArchiveJobPrivate() override = default;
 
 private:
-    GpgME::Error startIt() override
-    {
-        Q_ASSERT(!"Not supported by this Job class.");
-        return Error::fromCode(GPG_ERR_NOT_SUPPORTED);
-    }
+    GpgME::Error startIt() override;
 
     void startNow() override
     {
@@ -89,19 +87,9 @@ QGpgMEDecryptVerifyArchiveJob::QGpgMEDecryptVerifyArchiveJob(Context *context)
 }
 
 static QGpgMEDecryptVerifyArchiveJob::result_type decrypt_verify(Context *ctx,
-                                                                 QThread *thread,
-                                                                 const std::weak_ptr<QIODevice> &cipherText_,
+                                                                 const GpgME::Data &indata,
                                                                  const QString &outputDirectory)
 {
-    const std::shared_ptr<QIODevice> cipherText = cipherText_.lock();
-    const _detail::ToThreadMover ctMover(cipherText, thread);
-
-    QGpgME::QIODeviceDataProvider in{cipherText};
-    Data indata(&in);
-    if (!cipherText->isSequential()) {
-        indata.setSizeHint(cipherText->size());
-    }
-
     Data outdata;
     if (!outputDirectory.isEmpty()) {
         outdata.setFileName(outputDirectory.toStdString());
@@ -113,13 +101,39 @@ static QGpgMEDecryptVerifyArchiveJob::result_type decrypt_verify(Context *ctx,
     return std::make_tuple(res.first, res.second, log, ae);
 }
 
+static QGpgMEDecryptVerifyArchiveJob::result_type decrypt_verify_from_io_device(Context *ctx,
+                                                                                QThread *thread,
+                                                                                const std::weak_ptr<QIODevice> &cipherText_,
+                                                                                const QString &outputDirectory)
+{
+    const std::shared_ptr<QIODevice> cipherText = cipherText_.lock();
+    const _detail::ToThreadMover ctMover(cipherText, thread);
+    QGpgME::QIODeviceDataProvider in{cipherText};
+    Data indata(&in);
+    if (!cipherText->isSequential()) {
+        indata.setSizeHint(cipherText->size());
+    }
+
+    return decrypt_verify(ctx, indata, outputDirectory);
+}
+
+static QGpgMEDecryptVerifyArchiveJob::result_type decrypt_verify_from_file_name(Context *ctx,
+                                                                                const QString &inputFile,
+                                                                                const QString &outputDirectory)
+{
+    Data indata;
+    indata.setFileName(QFile::encodeName(inputFile).constData());
+
+    return decrypt_verify(ctx, indata, outputDirectory);
+}
+
 GpgME::Error QGpgMEDecryptVerifyArchiveJob::start(const std::shared_ptr<QIODevice> &cipherText)
 {
     if (!cipherText) {
         return Error::fromCode(GPG_ERR_INV_VALUE);
     }
 
-    run(std::bind(&decrypt_verify,
+    run(std::bind(&decrypt_verify_from_io_device,
                   std::placeholders::_1,
                   std::placeholders::_2,
                   std::placeholders::_3,
@@ -128,4 +142,17 @@ GpgME::Error QGpgMEDecryptVerifyArchiveJob::start(const std::shared_ptr<QIODevic
     return {};
 }
 
+GpgME::Error QGpgMEDecryptVerifyArchiveJobPrivate::startIt()
+{
+    if (m_inputFilePath.isEmpty()) {
+        return Error::fromCode(GPG_ERR_INV_VALUE);
+    }
+
+    q->run([=](Context *ctx) {
+        return decrypt_verify_from_file_name(ctx, m_inputFilePath, m_outputDirectory);
+    });
+
+    return {};
+}
+
 #include "qgpgmedecryptverifyarchivejob.moc"
diff --git a/lang/qt/tests/run-decryptverifyarchivejob.cpp b/lang/qt/tests/run-decryptverifyarchivejob.cpp
index cc588fcc..59073458 100644
--- a/lang/qt/tests/run-decryptverifyarchivejob.cpp
+++ b/lang/qt/tests/run-decryptverifyarchivejob.cpp
@@ -40,7 +40,6 @@
 #include <QCommandLineParser>
 #include <QCoreApplication>
 #include <QDebug>
-#include <QFile>
 
 #include <context.h>
 #include <decryptionresult.h>
@@ -85,20 +84,6 @@ CommandLineOptions parseCommandLine(const QStringList &arguments)
     return options;
 }
 
-std::shared_ptr<QIODevice> createInput(const QString &fileName)
-{
-    std::shared_ptr<QFile> input;
-
-    if (!QFile::exists(fileName)) {
-        qCritical() << "Error: File" << fileName << "does not exist.";
-    } else {
-        input.reset(new QFile{fileName});
-        input->open(QIODevice::ReadOnly);
-    }
-
-    return input;
-}
-
 int main(int argc, char **argv)
 {
     GpgME::initializeLibrary();
@@ -113,16 +98,12 @@ int main(int argc, char **argv)
         return 1;
     }
 
-    auto input = createInput(options.archiveName);
-    if (!input) {
-        return 1;
-    }
-
     auto job = QGpgME::openpgp()->decryptVerifyArchiveJob();
     if (!job) {
         std::cerr << "Error: Could not create job" << std::endl;
         return 1;
     }
+    job->setInputFile(options.archiveName);
     job->setOutputDirectory(options.outputDirectory);
     QObject::connect(job, &QGpgME::DecryptVerifyArchiveJob::result, &app, [](const GpgME::DecryptionResult &decryptionResult, const GpgME::VerificationResult &verificationResult, const QString &auditLog, const GpgME::Error &) {
         std::cerr << "Diagnostics: " << auditLog << std::endl;
@@ -131,7 +112,7 @@ int main(int argc, char **argv)
         qApp->quit();
     });
 
-    const auto err = job->start(input);
+    const auto err = job->startIt();
     if (err) {
         std::cerr << "Error: Starting the job failed: " << err.asString() << std::endl;
         return 1;