From 59dc585ccd070ef94ba7a5dfe173a803b1dfd41f Mon Sep 17 00:00:00 2001 From: "Marco Trevisan (Treviño)" Date: Mon, 19 Feb 2024 21:41:44 +0100 Subject: egismoc: Simplify check bytes computation We use big endian values for generating the check bytes, but we can do the same logic in a simpler way. --- libfprint/drivers/egismoc/egismoc.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/libfprint/drivers/egismoc/egismoc.c b/libfprint/drivers/egismoc/egismoc.c index c33809e..960df14 100644 --- a/libfprint/drivers/egismoc/egismoc.c +++ b/libfprint/drivers/egismoc/egismoc.c @@ -293,19 +293,21 @@ egismoc_get_check_bytes (const guchar *value, { fp_dbg ("Get check bytes"); EgisMocCheckBytes check_bytes; - guint16 big_endian_values[(int) ((value_length + 1) / 2)]; + const size_t steps = (value_length + 1) / 2; + guint16 big_endian_values[steps]; size_t sum_values = 0; - int s = 0; - for (int i = 0; i < value_length; i = i + 2, s++) + for (int i = 0, j = 0; i < value_length; i += 2, j++) { - if (i + 1 < value_length) - big_endian_values[s] = (((guint16) value[i + 1]) << 8) | (0x00ff & value[i]); - else - big_endian_values[s] = (((guint16) 0x00) << 8) | (0x00ff & value[i]); + big_endian_values[j] = 0; + + if (i < value_length - 1) + big_endian_values[j] = value[i + 1] << 8; + + big_endian_values[j] |= (value[i] & 0x00ff); } - for (int i = 0; i < s; i++) + for (int i = 0; i < steps; i++) sum_values += big_endian_values[i]; check_bytes.check_value = 0xffff - (sum_values % 0xffff); -- cgit v1.2.3