[PATCH 4/6 v2] Bluetooth: Refactor UUID-16 list generation into its own function

[Johan Hedberg <johan.hedberg@gmail.com>]

From: Johan Hedberg <johan.hedberg@intel.com>

We will need to create three separate UUID lists in the EIR data (for
16, 32 and 128 bit UUIDs) so the code is easier to follow if each list
is generated in their own function.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
---
 net/bluetooth/mgmt.c |   72 ++++++++++++++++++++++++++++----------------------
 1 file changed, 40 insertions(+), 32 deletions(-)

diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index abf941d..3c8e69f 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -435,11 +435,48 @@ static u32 get_current_settings(struct hci_dev *hdev)
 
 #define PNP_INFO_SVCLASS_ID		0x1200
 
+static u8 *create_uuid16_list(struct hci_dev *hdev, u8 *data, ptrdiff_t len)
+{
+	u8 *ptr = data, *uuids_start = NULL;
+	struct bt_uuid *uuid;
+
+	if (len < 4)
+		return ptr;
+
+	list_for_each_entry(uuid, &hdev->uuid16, list) {
+		u16 uuid16;
+
+		uuid16 = get_unaligned_le16(&uuid->uuid[12]);
+		if (uuid16 < 0x1100)
+			continue;
+
+		if (uuid16 == PNP_INFO_SVCLASS_ID)
+			continue;
+
+		if (!uuids_start) {
+			uuids_start = ptr;
+			uuids_start[0] = 1;
+			uuids_start[1] = EIR_UUID16_ALL;
+			ptr += 2;
+		}
+
+		/* Stop if not enough space to put next UUID */
+		if ((ptr - data) + sizeof(u16) > len) {
+			uuids_start[1] = EIR_UUID16_SOME;
+			break;
+		}
+
+		*ptr++ = (uuid16 & 0x00ff);
+		*ptr++ = (uuid16 & 0xff00) >> 8;
+		uuids_start[0] += sizeof(uuid16);
+	}
+
+	return ptr;
+}
+
 static void create_eir(struct hci_dev *hdev, u8 *data)
 {
 	u8 *ptr = data;
-	u8 *uuids_start;
-	struct bt_uuid *uuid;
 	size_t name_len;
 
 	name_len = strlen(hdev->dev_name);
@@ -480,36 +517,7 @@ static void create_eir(struct hci_dev *hdev, u8 *data)
 		ptr += 10;
 	}
 
-	uuids_start = NULL;
-
-	/* Group all UUID16 types */
-	list_for_each_entry(uuid, &hdev->uuid16, list) {
-		u16 uuid16;
-
-		uuid16 = get_unaligned_le16(&uuid->uuid[12]);
-		if (uuid16 < 0x1100)
-			continue;
-
-		if (uuid16 == PNP_INFO_SVCLASS_ID)
-			continue;
-
-		if (!uuids_start) {
-			uuids_start = ptr;
-			uuids_start[0] = 1;
-			uuids_start[1] = EIR_UUID16_ALL;
-			ptr += 2;
-		}
-
-		/* Stop if not enough space to put next UUID */
-		if ((ptr - data) + 2 + sizeof(u16) > HCI_MAX_EIR_LENGTH) {
-			uuids_start[1] = EIR_UUID16_SOME;
-			break;
-		}
-
-		*ptr++ = (uuid16 & 0x00ff);
-		*ptr++ = (uuid16 & 0xff00) >> 8;
-		uuids_start[0] += sizeof(uuid16);
-	}
+	ptr = create_uuid16_list(hdev, ptr, HCI_MAX_EIR_LENGTH - (ptr - data));
 }
 
 static int update_eir(struct hci_dev *hdev)
-- 
1.7.10.4