From aee59a33bea1fe66a8ff8e8ac63bb045392ab28c Mon Sep 17 00:00:00 2001
From: Jef Driesen <jefdriesen@users.sourceforge.net>
Date: Tue, 29 Aug 2017 20:25:55 +0200
Subject: [PATCH] Add support for querying the available built-in transports

Because the list of supported built-in transports depends on the
availability of external libraries (libusb, hidapi) and the operating
system, the application needs some mechanism to retrieve this
information at runtime. Therefore, a new dc_context_get_transports()
function is added, which returns a bitmask with all the available
built-in transports.
---
 include/libdivecomputer/context.h |  3 +++
 src/context.c                     | 36 +++++++++++++++++++++++++++++++
 src/libdivecomputer.symbols       |  1 +
 3 files changed, 40 insertions(+)

diff --git a/include/libdivecomputer/context.h b/include/libdivecomputer/context.h
index 861dbeb..824b67b 100644
--- a/include/libdivecomputer/context.h
+++ b/include/libdivecomputer/context.h
@@ -53,6 +53,9 @@ dc_context_set_loglevel (dc_context_t *context, dc_loglevel_t loglevel);
 dc_status_t
 dc_context_set_logfunc (dc_context_t *context, dc_logfunc_t logfunc, void *userdata);
 
+unsigned int
+dc_context_get_transports (dc_context_t *context);
+
 #ifdef __cplusplus
 }
 #endif /* __cplusplus */
diff --git a/src/context.c b/src/context.c
index 181fef1..8c73aca 100644
--- a/src/context.c
+++ b/src/context.c
@@ -19,6 +19,10 @@
  * MA 02110-1301 USA
  */
 
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
 #include <stdlib.h>
 #include <stdio.h>
 #include <stdarg.h>
@@ -313,3 +317,35 @@ dc_context_hexdump (dc_context_t *context, dc_loglevel_t loglevel, const char *f
 
 	return DC_STATUS_SUCCESS;
 }
+
+unsigned int
+dc_context_get_transports (dc_context_t *context)
+{
+	UNUSED(context);
+
+	return DC_TRANSPORT_SERIAL
+#if defined(HAVE_LIBUSB)
+		| DC_TRANSPORT_USB
+#endif
+#if defined(HAVE_HIDAPI)
+		| DC_TRANSPORT_USBHID
+#elif defined(HAVE_LIBUSB) && !defined(__APPLE__)
+		| DC_TRANSPORT_USBHID
+#endif
+#ifdef _WIN32
+#ifdef HAVE_AF_IRDA_H
+		| DC_TRANSPORT_IRDA
+#endif
+#ifdef HAVE_WS2BTH_H
+		| DC_TRANSPORT_BLUETOOTH
+#endif
+#else /* _WIN32 */
+#ifdef HAVE_LINUX_IRDA_H
+		| DC_TRANSPORT_IRDA
+#endif
+#ifdef HAVE_BLUEZ
+		| DC_TRANSPORT_BLUETOOTH
+#endif
+#endif /* _WIN32 */
+	;
+}
diff --git a/src/libdivecomputer.symbols b/src/libdivecomputer.symbols
index 6f95948..4433a68 100644
--- a/src/libdivecomputer.symbols
+++ b/src/libdivecomputer.symbols
@@ -21,6 +21,7 @@ dc_context_new
 dc_context_free
 dc_context_set_loglevel
 dc_context_set_logfunc
+dc_context_get_transports
 
 dc_iterator_next
 dc_iterator_free