libusbg: examples: Add sample application to export gadget

Add sample C code which shows how to use new functionality
of libusbg - gadget export. This program allows to export
chosen gadget from configfs to a file.

Signed-off-by: Krzysztof Opasiak <k.opasiak@samsung.com>

2 files changed, 83 insertions, 1 deletions

diff --git a/examples/Makefile.am b/examples/Makefile.am
index abafe3c..aeb0273 100644
--- a/examples/Makefile.am
+++ b/examples/Makefile.am
@@ -1,7 +1,8 @@
-bin_PROGRAMS = show-gadgets gadget-acm-ecm gadget-vid-pid-remove gadget-ffs
+bin_PROGRAMS = show-gadgets gadget-acm-ecm gadget-vid-pid-remove gadget-ffs gadget-export
 gadget_acm_ecm_SOURCES = gadget-acm-ecm.c
 show_gadgets_SOURCES = show-gadgets.c
 gadget_vid_pid_remove_SOURCES = gadget-vid-pid-remove.c
 gadget_ffs_SOURCES = gadget-ffs.c
+gadget_export_SOURCE = gadget-export.c
 AM_CPPFLAGS=-I../include/
 AM_LDFLAGS=-L../src/ -lusbg
diff --git a/examples/gadget-export.c b/examples/gadget-export.c
new file mode 100644
index 0000000..9d51e9e
--- /dev/null
+++ b/examples/gadget-export.c
@@ -0,0 +1,81 @@
+/*
+ * Copyright (C) 2014 Samsung Electronics
+ *
+ * Krzysztof Opasiak <k.opasiak@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+/**
+ * @file gadget-export.c
+ * @example gadget-export.c
+ * This is an example of how to export a gadget to file.
+ * Common reason of doing this is to share schema of gadget
+ * between different devices or preserve gadget between reboots.
+ */
+
+#include <errno.h>
+#include <string.h>
+#include <stdio.h>
+#include <usbg/usbg.h>
+
+int main(int argc, char **argv)
+{
+	usbg_state *s;
+	usbg_gadget *g;
+	int ret = -EINVAL;
+	int usbg_ret;
+	FILE *output;
+
+	if (argc != 3) {
+		fprintf(stderr, "Usage: gadget-export gadget_name file_name\n");
+		return ret;
+	}
+
+	/* Prepare output file */
+	output = fopen(argv[2], "w");
+	if (!output) {
+		fprintf(stderr, "Error on fopen. Error: %s\n", strerror(errno));
+		goto out1;
+	}
+
+	/* Do gadget exporting */
+	usbg_ret = usbg_init("/sys/kernel/config", &s);
+	if (usbg_ret != USBG_SUCCESS) {
+		fprintf(stderr, "Error on USB gadget init\n");
+		fprintf(stderr, "Error: %s : %s\n", usbg_error_name(usbg_ret),
+				usbg_strerror(usbg_ret));
+		goto out2;
+	}
+
+	g = usbg_get_gadget(s, argv[1]);
+	if (!g) {
+		fprintf(stderr, "Error on get gadget\n");
+		goto out3;
+	}
+
+	usbg_ret = usbg_export_gadget(g, output);
+	if (usbg_ret != USBG_SUCCESS) {
+		fprintf(stderr, "Error on export gadget\n");
+		fprintf(stderr, "Error: %s : %s\n", usbg_error_name(usbg_ret),
+				usbg_strerror(usbg_ret));
+		goto out3;
+	}
+
+	ret = 0;
+
+out3:
+	usbg_cleanup(s);
+out2:
+	fclose(output);
+out1:
+	return ret;
+}