C++: Wrap resource access API

Introduce a ResourceReader delegate class with virtual methods
corresponding to the C callback functions.

diff --git a/bindings/cxx/classes.cpp b/bindings/cxx/classes.cpp
index 25ac45b6235d166eeb735b50e7b49ac399969e45..a944faa21b879aaa191ddf7acf4e224e27c2a195 100644 (file)
--- a/bindings/cxx/classes.cpp
+++ b/bindings/cxx/classes.cpp
@@ -72,6 +72,50 @@ Error::~Error() throw()
 {
 }
 
+ResourceReader::~ResourceReader()
+{
+}
+
+SR_PRIV int ResourceReader::open_callback(struct sr_resource *res,
+               const char *name, void *cb_data)
+{
+       try {
+               auto *const reader = static_cast<ResourceReader*>(cb_data);
+               reader->open(res, name);
+       } catch (const Error &err) {
+               return err.result;
+       } catch (...) {
+               return SR_ERR;
+       }
+       return SR_OK;
+}
+
+SR_PRIV int ResourceReader::close_callback(struct sr_resource *res, void *cb_data)
+{
+       try {
+               auto *const reader = static_cast<ResourceReader*>(cb_data);
+               reader->close(res);
+       } catch (const Error &err) {
+               return err.result;
+       } catch (...) {
+               return SR_ERR;
+       }
+       return SR_OK;
+}
+
+SR_PRIV ssize_t ResourceReader::read_callback(const struct sr_resource *res,
+               void *buf, size_t count, void *cb_data)
+{
+       try {
+               auto *const reader = static_cast<ResourceReader*>(cb_data);
+               return reader->read(res, buf, count);
+       } catch (const Error &err) {
+               return err.result;
+       } catch (...) {
+               return SR_ERR;
+       }
+}
+
 shared_ptr<Context> Context::create()
 {
        return shared_ptr<Context>(new Context(), Context::Deleter());
@@ -196,13 +240,26 @@ void Context::set_log_callback(LogCallbackFunction callback)
 {
        _log_callback = callback;
        check(sr_log_callback_set(call_log_callback, &_log_callback));
-} 
+}
 
 void Context::set_log_callback_default()
 {
        check(sr_log_callback_set_default());
        _log_callback = nullptr;
-} 
+}
+
+void Context::set_resource_reader(ResourceReader *reader)
+{
+       if (reader) {
+               check(sr_resource_set_hooks(_structure,
+                               &ResourceReader::open_callback,
+                               &ResourceReader::close_callback,
+                               &ResourceReader::read_callback, reader));
+       } else {
+               check(sr_resource_set_hooks(_structure,
+                               nullptr, nullptr, nullptr, nullptr));
+       }
+}
 
 shared_ptr<Session> Context::create_session()
 {

diff --git a/bindings/cxx/include/libsigrokcxx/libsigrokcxx.hpp b/bindings/cxx/include/libsigrokcxx/libsigrokcxx.hpp
index f96901f335ffbeef4be67262fbf428f895ab3ccb..b9e8a4f268288ff0c1b916d15e9e22b6f6eb7ece 100644 (file)
--- a/bindings/cxx/include/libsigrokcxx/libsigrokcxx.hpp
+++ b/bindings/cxx/include/libsigrokcxx/libsigrokcxx.hpp
@@ -232,6 +232,29 @@ protected:
 /** Type of log callback */
 typedef function<void(const LogLevel *, string message)> LogCallbackFunction;
 
+/** Resource reader delegate. */
+class SR_API ResourceReader
+{
+public:
+       ResourceReader() {}
+       virtual ~ResourceReader();
+private:
+       /** Resource open hook. */
+       virtual void open(struct sr_resource *res, string name) = 0;
+       /** Resource close hook. */
+       virtual void close(struct sr_resource *res) = 0;
+       /** Resource read hook. */
+       virtual size_t read(const struct sr_resource *res, void *buf, size_t count) = 0;
+
+       static SR_PRIV int open_callback(struct sr_resource *res,
+                       const char *name, void *cb_data);
+       static SR_PRIV int close_callback(struct sr_resource *res,
+                       void *cb_data);
+       static SR_PRIV ssize_t read_callback(const struct sr_resource *res,
+                       void *buf, size_t count, void *cb_data);
+       friend class Context;
+};
+
 /** The global libsigrok context */
 class SR_API Context : public UserOwned<Context, struct sr_context>
 {
@@ -258,6 +281,9 @@ public:
        void set_log_callback(LogCallbackFunction callback);
        /** Set the log callback to the default handler. */
        void set_log_callback_default();
+       /** Install a delegate for reading resource files.
+        * @param reader The resource reader delegate, or nullptr to unset. */
+       void set_resource_reader(ResourceReader *reader);
        /** Create a new session. */
        shared_ptr<Session> create_session();
        /** Create a new user device. */