diff options
Diffstat (limited to 'extmod/os_dupterm.c')
| -rw-r--r-- | extmod/os_dupterm.c | 33 |
1 files changed, 27 insertions, 6 deletions
diff --git a/extmod/os_dupterm.c b/extmod/os_dupterm.c index cfd1c6261..298983e9c 100644 --- a/extmod/os_dupterm.c +++ b/extmod/os_dupterm.c @@ -94,6 +94,22 @@ uintptr_t mp_os_dupterm_poll(uintptr_t poll_flags) { } int mp_os_dupterm_rx_chr(void) { + #if MICROPY_PY_OS_DUPTERM_NOTIFY + // When os.dupterm_notify() is enabled it is usually called from a scheduled + // function, via mp_os_dupterm_notify(). That can lead to recursive calls of + // this function when this function is called from mp_hal_stdin_rx_chr(): + // - mp_hal_stdin_rx_chr() + // - mp_os_dupterm_rx_chr() + // - <Python code> + // - os.dupterm_notify() is scheduled via interrupt/event + // - <Python code> runs scheduled code (eg WebREPL -> rp2.Flash().writeblocks()) + // - mp_os_dupterm_notify() + // - mp_os_dupterm_rx_chr() + // Break that cycle by locking the scheduler during this function's duration. + mp_sched_lock(); + #endif + + int ret = -1; // no chars available for (size_t idx = 0; idx < MICROPY_PY_OS_DUPTERM; ++idx) { if (MP_STATE_VM(dupterm_objs[idx]) == MP_OBJ_NULL) { continue; @@ -106,7 +122,8 @@ int mp_os_dupterm_rx_chr(void) { const mp_stream_p_t *stream_p = mp_get_stream(MP_STATE_VM(dupterm_objs[idx])); mp_uint_t out_sz = stream_p->read(MP_STATE_VM(dupterm_objs[idx]), buf, 1, &errcode); if (errcode == 0 && out_sz != 0) { - return buf[0]; + ret = buf[0]; + break; } else { continue; } @@ -132,20 +149,24 @@ int mp_os_dupterm_rx_chr(void) { } else { // read 1 byte nlr_pop(); - if (buf[0] == mp_interrupt_char) { + ret = buf[0]; + if (ret == mp_interrupt_char) { // Signal keyboard interrupt to be raised as soon as the VM resumes mp_sched_keyboard_interrupt(); - return -2; + ret = -2; } - return buf[0]; + break; } } else { mp_os_deactivate(idx, "dupterm: Exception in read() method, deactivating: ", MP_OBJ_FROM_PTR(nlr.ret_val)); } } - // No chars available - return -1; + #if MICROPY_PY_OS_DUPTERM_NOTIFY + mp_sched_unlock(); + #endif + + return ret; } void mp_os_dupterm_tx_strn(const char *str, size_t len) { |