From: Dmitry Bogatov <d.bogatov@samsung.com>
Date: Tue, 26 Nov 2013 13:50:34 +0000 (+0400)
Subject: [REFACTOR] Refactor semi-pure calculation of msg_data payload length
X-Git-Tag: Tizen_SDK_2.3~106
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=ad6630a40e76c20aefb05295f4335df6e77eb005;p=platform%2Fcore%2Fsystem%2Fswap-manager.git

[REFACTOR] Refactor semi-pure calculation of msg_data payload length

Change-Id: I25d46ab034e85055e8e7945984c2b72462031bca
Signed-off-by: Dmitry Bogatov <d.bogatov@samsung.com>
---

diff --git a/daemon/da_protocol.h b/daemon/da_protocol.h
index 1bb3e89..573bcd8 100644
--- a/daemon/da_protocol.h
+++ b/daemon/da_protocol.h
@@ -268,6 +268,14 @@ struct process_info_t {
 	float load;
 };
 
+/**
+ * NOTE:
+ *
+ * Adding pointer memebers to struct %system_info_t REQUIRES updating code,
+ * calculating length of bytevector, suitable for serializing it. See
+ * msg_data_payload_length()
+ *
+ */
 struct system_info_t {
 	// system_cpu
 	float app_cpu_usage;
diff --git a/daemon/sys_stat.c b/daemon/sys_stat.c
index 8fd29c2..31b849a 100644
--- a/daemon/sys_stat.c
+++ b/daemon/sys_stat.c
@@ -2532,19 +2532,14 @@ int sys_stat_prepare(void)
 	return 0;
 }
 
-struct msg_data_t *pack_system_info(struct system_info_t *sys_info)
+static uint32_t msg_data_payload_length(const struct system_info_t *sys_info)
 {
-	struct msg_data_t *msg = NULL;
-	char *p = NULL;
-	int i = 0;
-	uint32_t len = 0;
+	uint32_t len = sizeof(*sys_info);
 
-	len += sizeof(*sys_info);
-
-	// num_of_cpu is unknown at compile time
+	/* num_of_cpu is unknown at compile time */
 	len += 2 * num_of_cpu * sizeof(float);
 
-	// subtract pointers
+	/* subtract pointers */
 	len -= sizeof(sys_info->cpu_frequency) + sizeof(sys_info->cpu_load);
 	len -= sizeof(sys_info->thread_load) + sizeof(sys_info->process_load);
 
@@ -2556,6 +2551,16 @@ struct msg_data_t *pack_system_info(struct system_info_t *sys_info)
 		len += sys_info->count_of_processes *
 			sizeof(*sys_info->process_load);
 
+	return len;
+}
+
+struct msg_data_t *pack_system_info(struct system_info_t *sys_info)
+{
+	const int len = msg_data_payload_length(sys_info);
+	struct msg_data_t *msg = NULL;
+	char *p = NULL;
+	int i = 0;
+
 	msg = malloc(MSG_DATA_HDR_LEN + len);
 	if (!msg) {
 		LOGE("Cannot alloc message: %d bytes\n", len);