From 28228e7272b84ab03ab3b86becd57d69eed1dbfb Mon Sep 17 00:00:00 2001
From: Bastian Dehn <hhaalo@arcor.de>
Date: Fri, 23 Feb 2024 17:30:22 +0100
Subject: [PATCH] fix read empty data with test

---
 src/kds_s2000w_handler.c          | 40 ++++++++++++++++++++-----------
 src/kds_s2000w_handler.h          |  2 ++
 src/kds_s2000w_net.c              | 10 ++++----
 tests/kds_s2000w_net_read_tests.c | 39 ++++++++++++++++++++++++++++++
 tests/runtests.c                  |  2 ++
 5 files changed, 75 insertions(+), 18 deletions(-)

diff --git a/src/kds_s2000w_handler.c b/src/kds_s2000w_handler.c
index bd5eec9..e618767 100644
--- a/src/kds_s2000w_handler.c
+++ b/src/kds_s2000w_handler.c
@@ -155,12 +155,8 @@ void _get_current_scan_status(handler* h)
 	sleep(1);
 }
 
-void kds_s2000w_handler_open(const char* devicename, void** handle)
+handler* init_handler()
 {
-	debug_printf(ALL, "kds_s2000w_handler_open");
-	if (strcmp(devicename, "kds_s2000w_net") != 0)
-		return;
-
 	handler* h = malloc(sizeof(handler));
 	h->current_scan_status = malloc(sizeof(scan_status));
 	h->current_metadata = malloc(sizeof(metadata));
@@ -188,6 +184,30 @@ void kds_s2000w_handler_open(const char* devicename, void** handle)
 	h->read_info->readed_bytes_per_line = 0;
 	h->read_info->readed_lines = 0;
 
+	return h;
+}
+
+void free_handler(handler* h)
+{
+	free(h->current_scan_status);
+	h->current_scan_status = NULL;
+	free(h->current_metadata->image);
+	h->current_metadata->image = NULL;
+	free(h->current_metadata);
+	h->current_metadata = NULL;
+	free(h->read_info);
+	h->read_info = NULL;
+	free(h);
+	h = NULL;
+}
+
+void kds_s2000w_handler_open(const char* devicename, void** handle)
+{
+	debug_printf(ALL, "kds_s2000w_handler_open");
+	if (strcmp(devicename, "kds_s2000w_net") != 0)
+		return;
+
+	handler* h = init_handler();
 	*handle = h;
 
 	init_gamma_table();
@@ -252,15 +272,7 @@ void kds_s2000w_handler_close(void* handle)
 
 	kds_s2000w_client_close_session(h->sessionid);
 	h->sessionid = 0;
-	free(h->current_scan_status);
-	h->current_scan_status = NULL;
-	free(h->current_metadata->image);
-	h->current_metadata->image = NULL;
-	free(h->read_info);
-	h->read_info = NULL;
-	free(h->current_metadata);
-	h->current_metadata = NULL;
-	free(h);
+	free_handler(h);
 	h = NULL;
 }
 
diff --git a/src/kds_s2000w_handler.h b/src/kds_s2000w_handler.h
index 6f1798f..fdf6a66 100644
--- a/src/kds_s2000w_handler.h
+++ b/src/kds_s2000w_handler.h
@@ -47,6 +47,8 @@ typedef struct {
 	readinfo* read_info;
 } handler;
 
+handler* init_handler();
+void free_handler(handler* h);
 void kds_s2000w_handler_open(const char* devicename, void** handle);
 void kds_s2000w_handler_close(void* handle);
 void kds_s2000w_handler_get_option(void* handle, int option, void* value);
diff --git a/src/kds_s2000w_net.c b/src/kds_s2000w_net.c
index 6a15bdc..ad80a36 100644
--- a/src/kds_s2000w_net.c
+++ b/src/kds_s2000w_net.c
@@ -182,11 +182,13 @@ SANE_Status _sane_kds_s2000w_net_read(SANE_Handle handle, SANE_Byte* data,
 		sleep(1);
 		kds_s2000w_handler_open("kds_s2000w_net", handle);
 		return SANE_STATUS_CANCELLED;
-	}
+	}	
 
-	int skip_header_bytes = _sane_kds_s2000w_net_find_first_data_byte(h->current_metadata->image);
-	if (h->read_info->read_size <= 0)
-		h->read_info->read_size += skip_header_bytes;
+	if (h->current_metadata->image != NULL) {
+		int skip_header_bytes = _sane_kds_s2000w_net_find_first_data_byte(h->current_metadata->image);
+		if (h->read_info->read_size <= 0)
+			h->read_info->read_size += skip_header_bytes;
+	}
 
 	if (h->read_info->readed_lines >= h->current_metadata->lines) {
 		*length = 0;
diff --git a/tests/kds_s2000w_net_read_tests.c b/tests/kds_s2000w_net_read_tests.c
index 1324843..acc35ea 100644
--- a/tests/kds_s2000w_net_read_tests.c
+++ b/tests/kds_s2000w_net_read_tests.c
@@ -37,6 +37,45 @@ START_TEST(sane_kds_s2000w_net_read_cancel_test)
 }
 END_TEST
 
+START_TEST(sane_kds_s2000w_net_read_without_data)
+{
+	int length = 0;
+	handler* h = init_handler();
+	char* dataptr = malloc(sizeof(char));
+
+	SANE_Status status = _sane_kds_s2000w_net_read(h, dataptr, 65536, &length);
+
+	ck_assert_int_eq(status, SANE_STATUS_EOF);
+
+	free(dataptr);
+	dataptr = NULL;
+	free_handler(h);
+	h = NULL;
+}
+END_TEST
+
+START_TEST(sane_kds_s2000w_net_read_empty_image)
+{
+	int length = 0;
+	handler* h = init_handler();
+	h->current_metadata->size = 1;
+	char* image = malloc(sizeof(char));
+	image[0] = 0;
+	h->current_metadata->image = image;
+	char* dataptr = malloc(sizeof(char));
+
+	SANE_Status status = _sane_kds_s2000w_net_read(h, dataptr, 65536, &length);
+
+	ck_assert_int_eq(status, SANE_STATUS_EOF);
+
+	free(dataptr);
+	dataptr = NULL;
+	image = NULL;
+	free_handler(h);
+	h = NULL;
+}
+END_TEST
+
 START_TEST(sane_kds_s2000w_net_read_all_lines_test)
 {
 	handler h;
diff --git a/tests/runtests.c b/tests/runtests.c
index 696c6cd..69b0c8c 100644
--- a/tests/runtests.c
+++ b/tests/runtests.c
@@ -24,6 +24,8 @@ Suite* net_read()
 	TCase* net_read = tcase_create("read");
 	tcase_add_test(net_read, sane_kds_s2000w_net_find_first_data_byte_test);
 	tcase_add_test(net_read, sane_kds_s2000w_net_read_cancel_test);
+	tcase_add_test(net_read, sane_kds_s2000w_net_read_without_data);
+	tcase_add_test(net_read, sane_kds_s2000w_net_read_empty_image);
 	tcase_add_test(net_read, sane_kds_s2000w_net_read_all_lines_test);
 	tcase_add_test(net_read, sane_kds_s2000w_net_read_test);
 	tcase_add_test(net_read, sane_kds_s2000w_net_read_bytes_per_line_bigger_test);
-- 
2.39.5