view ringtools/imy/durations.c @ 965:2969032bdfac

fcup-smsend[mult]: fix buglet in K&R C NULL pointer passing The only 100% safe way to pass a NULL pointer as a function argument in K&R C is to cast 0 to a pointer type; failing to do so may cause mysterious bugs (invalid stack frames or garbage in argument registers) on 64-bit machines. This issue has already been fixed in most of FC host tools, but I just found some missed spots: passing of NULL UDH to PDU encoding functions in fcup-smsend[mult] in the case of single (not concatenated) SMS.
author Mychaela Falconia <falcon@freecalypso.org>
date Fri, 01 Sep 2023 07:33:51 +0000
parents fd4c9bc7835d
children
line wrap: on
line source

/*
 * This module implements the step of precomputing various note durations
 * in TDMA frames.
 */

extern unsigned beats_per_min;
unsigned tdma_durations[6][4];

static float modifier_values[4] = {1.0f, 1.5f, 1.75f, 2.0f / 3.0f};

compute_note_durations()
{
	float beat_ref, basic_ms[6], dur_ms;
	unsigned dur_tdma;
	int i, j;

	beat_ref = 60000.0f / beats_per_min;
	basic_ms[0] = beat_ref * 4.0f;
	basic_ms[1] = beat_ref * 2.0f;
	basic_ms[2] = beat_ref;
	basic_ms[3] = beat_ref / 2.0f;
	basic_ms[4] = beat_ref / 4.0f;
	basic_ms[5] = beat_ref / 8.0f;
	for (i = 0; i < 6; i++) {
		for (j = 0; j < 4; j++) {
			dur_ms = basic_ms[i] * modifier_values[j];
			dur_tdma = dur_ms * 13.0f / 60.0f + 0.5f;
			tdma_durations[i][j] = dur_tdma;
		}
	}
}