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| author | Joakim Tufvegren <jocke@barbanet.com> | 2021-08-03 23:40:08 +0200 |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2021-08-04 07:40:08 +1000 |
| commit | 2b097d670a9fa458b8d059f824a0cbbd5b6c6659 (patch) | |
| tree | 4a6d2acb69055bab2a408efe3bfacfcbdaccd57d /quantum/wpm.c | |
| parent | f2fc23d1b13045f991b0269c2853e3219b052b80 (diff) | |
| download | qmk_firmware-2b097d670a9fa458b8d059f824a0cbbd5b6c6659.tar.gz qmk_firmware-2b097d670a9fa458b8d059f824a0cbbd5b6c6659.zip | |
Fix overflows in WPM calculations (#13128)
* Fix overflow in WPM calculations.
First, the "fresh" WPM calculation could end up being up to 12000 (with
default `WPM_ESTIMATED_WORD_SIZE`) if keys were pressed more or less
simultaneously. This value has now been clamped down to 255, in effect
clamping WPM to its max value of 255.
Second, with `WPM_ALLOW_COUNT_REGRESSION` enabled, it was possible to
regress the WPM below 0 (i.e. to 255) by just repeatedly pressing
backspace.
* Fix WPM being limited to 235 due to float/int logic.
Diffstat (limited to 'quantum/wpm.c')
| -rw-r--r-- | quantum/wpm.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/quantum/wpm.c b/quantum/wpm.c index bec419a48e..e711e9fe73 100644 --- a/quantum/wpm.c +++ b/quantum/wpm.c @@ -17,6 +17,8 @@ #include "wpm.h" +#include <math.h> + // WPM Stuff static uint8_t current_wpm = 0; static uint16_t wpm_timer = 0; @@ -69,14 +71,22 @@ __attribute__((weak)) uint8_t wpm_regress_count(uint16_t keycode) { void update_wpm(uint16_t keycode) { if (wpm_keycode(keycode)) { if (wpm_timer > 0) { - current_wpm += ((60000 / timer_elapsed(wpm_timer) / WPM_ESTIMATED_WORD_SIZE) - current_wpm) * wpm_smoothing; + uint16_t latest_wpm = 60000 / timer_elapsed(wpm_timer) / WPM_ESTIMATED_WORD_SIZE; + if (latest_wpm > UINT8_MAX) { + latest_wpm = UINT8_MAX; + } + current_wpm += ceilf((latest_wpm - current_wpm) * wpm_smoothing); } wpm_timer = timer_read(); } #ifdef WPM_ALLOW_COUNT_REGRESSION uint8_t regress = wpm_regress_count(keycode); if (regress) { - current_wpm -= regress; + if (current_wpm < regress) { + current_wpm = 0; + } else { + current_wpm -= regress; + } wpm_timer = timer_read(); } #endif |