[PATCH v5 2/8] plugins: Extend the pin code callback with the call number

[Alex Deymo <deymo@chromium.org>]

The plugin's pin code callback doesn't know about the pairing process. It
just provides a pin code based on the information provided to this function.
Although limited state could be added through other new callbacks, this fix
achieves this by providing more information to the callback itself. The
new argument "attempt" states the pin callback attempt of the particular
plugin for the current pairing of the device. This allows a plugin to try
different pincodes for the same device in the same pairing process.

To signal that the plugin doesn't provide any pin code for the provided device
the current implementation returns 0 (an empty pin code). Analogously, with
this fix, a plugin should return 0 when it doesn't have any other pin code to
provide for the given device.
---
 plugins/wiimote.c | 7 ++++++-
 src/adapter.c     | 2 +-
 src/adapter.h     | 3 ++-
 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/plugins/wiimote.c b/plugins/wiimote.c
index 90d6d7b..12312b6 100644
--- a/plugins/wiimote.c
+++ b/plugins/wiimote.c
@@ -70,12 +70,17 @@ static const char *wii_names[] = {
 };
 
 static ssize_t wii_pincb(struct btd_adapter *adapter, struct btd_device *device,
-						char *pinbuf, gboolean *display)
+			char *pinbuf, gboolean *display, unsigned int attempt)
 {
 	uint16_t vendor, product;
 	char addr[18], name[25];
 	unsigned int i;
 
+	/* Only try the pin code once per device. If it's not correct then it's
+	 * an unknown device. */
+	if (attempt > 1)
+		return 0;
+
 	ba2str(device_get_address(device), addr);
 
 	vendor = btd_device_get_vendor(device);
diff --git a/src/adapter.c b/src/adapter.c
index b317d47..bf10268 100644
--- a/src/adapter.c
+++ b/src/adapter.c
@@ -4795,7 +4795,7 @@ static ssize_t btd_adapter_pin_cb_iter_next(
 
 	while (iter->it != NULL) {
 		cb = iter->it->data;
-		ret = cb(adapter, device, pin_buf, display);
+		ret = cb(adapter, device, pin_buf, display, iter->attempt);
 		iter->attempt++;
 		if (ret > 0)
 			return ret;
diff --git a/src/adapter.h b/src/adapter.h
index 425a11f..09d80c2 100644
--- a/src/adapter.h
+++ b/src/adapter.h
@@ -132,7 +132,8 @@ int btd_cancel_authorization(guint id);
 int btd_adapter_restore_powered(struct btd_adapter *adapter);
 
 typedef ssize_t (*btd_adapter_pin_cb_t) (struct btd_adapter *adapter,
-			struct btd_device *dev, char *out, gboolean *display);
+			struct btd_device *dev, char *out, gboolean *display,
+							unsigned int attempt);
 void btd_adapter_register_pin_cb(struct btd_adapter *adapter,
 						btd_adapter_pin_cb_t cb);
 void btd_adapter_unregister_pin_cb(struct btd_adapter *adapter,
-- 
1.8.2.1