Initial commit

.gitignore

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+*.swp

README.md

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+twinkl
+------
+
+A simple multiclient network protocol for your blinkenlights.
+

include/config.h

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+#ifndef _CONFIG_H_
+#define _CONFIG_H_
+
+/*
+ * Here be Configuration
+ */
+
+// Number of channels
+#define TWINKL_CHANNEL_COUNT 512
+
+// Number of priority levels
+#define TWINKL_LEVEL_COUNT 8
+
+
+/*
+ * Only automagic below this point
+ */
+
+// ceil(TWINKL_CHANNEL_COUNT / 8)
+#define TWINKL_MASK_BYTES ((TWINKL_CHANNEL_COUNT + 7) / 8)
+
+
+#endif

include/message.h

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+#ifndef _MESSAGE_H_
+#define _MESSAGE_H_
+
+#include <stdint.h>
+
+#include "config.h"
+#include "util.h"
+
+struct twinkl_message {
+
+	// Channel values from 0 to 255
+	uint8_t values[TWINKL_CHANNEL_COUNT];
+
+	/*
+	 * Mask bits
+	 *
+	 * If the value of channel X should be set,
+	 * set bit X % 8 in byte X / 8.
+     */
+	uint8_t mask[TWINKL_MASK_BYTES];
+
+	// Priority of this message.
+	uint8_t priority;
+};
+
+
+/*
+ * Static helper functions for messages
+ */ 
+static inline void twinkl_init_message(struct twinkl_message *msg) {
+	twinkl_memset(msg->values, 0, TWINKL_CHANNEL_COUNT);
+	twinkl_memset(msg->mask, 0, TWINKL_MASK_BYTES);
+	msg->priority = 0;
+}
+
+static inline void twinkl_set_value(struct twinkl_message *msg, uint16_t chan, uint8_t value) {
+	if(chan < TWINKL_CHANNEL_COUNT) {
+		msg->values[chan] = value;
+
+		uint16_t byte = chan / 8;
+		uint8_t bit = chan % 8;
+		msg->mask[byte] |= (1 << bit);
+	}
+}
+
+static inline void twinkl_unset_value(struct twinkl_message *msg, uint16_t chan) {
+	if(chan < TWINKL_CHANNEL_COUNT) {
+		msg->values[chan] = 0;
+
+		uint16_t byte = chan / 8;
+		uint8_t bit = chan % 8;
+		msg->mask[byte] &= ~(1 << bit);
+	}
+}
+
+static inline void twinkl_set_priority(struct twinkl_message *msg, uint8_t priority) {
+	if(priority < TWINKL_LEVEL_COUNT) {
+		msg->priority = priority;
+	}
+}
+
+#endif

include/twinkl.h

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+#ifndef _TWINKL_H_
+#define _TWINKL_H_
+
+#include <stdint.h>
+
+#include "message.h"
+
+void twinkl_init(void);
+
+void twinkl_process_message(struct twinkl_message* msg);
+
+uint8_t twinkl_has_changes(void);
+
+void twinkl_render(uint8_t *channels);
+
+
+#endif

include/util.h

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+#ifndef _UTIL_H_
+#define _UTIL_H_
+
+#include <stdlib.h>
+
+void* __attribute__((weak)) twinkl_memset(void *ptr, int value, size_t num);
+void* __attribute__((weak)) twinkl_memcpy(void * destination, const void * source, size_t num);
+
+#endif

twinkl.c

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+#include <stdint.h>
+
+#include "config.h"
+#include "util.h"
+#include "twinkl.h"
+
+
+uint8_t twinkl_channels[TWINKL_LEVEL_COUNT][TWINKL_CHANNEL_COUNT];
+uint8_t twinkl_masks[TWINKL_LEVEL_COUNT][TWINKL_MASK_BYTES];
+
+uint8_t twinkl_has_changed;
+
+
+void twinkl_init() {
+	twinkl_memset(twinkl_channels, 0, TWINKL_LEVEL_COUNT * TWINKL_CHANNEL_COUNT);
+	twinkl_memset(twinkl_masks, 0, TWINKL_LEVEL_COUNT * TWINKL_MASK_BYTES);
+
+	twinkl_has_changed = 0;
+}
+
+
+void twinkl_process_message(struct twinkl_message *msg) {
+	if(msg->priority < TWINKL_LEVEL_COUNT) {
+		twinkl_memcpy(twinkl_channels[msg->priority], msg->values, TWINKL_CHANNEL_COUNT);
+		twinkl_memcpy(twinkl_masks[msg->priority], msg->mask, TWINKL_MASK_BYTES);
+
+		twinkl_has_changed = 1;
+	}
+}
+
+
+uint8_t twinkl_has_changes() {
+	return twinkl_has_changed;
+}
+
+
+uint8_t get_mask_bit(uint8_t level, uint16_t channel) {
+	if(level >= TWINKL_LEVEL_COUNT && channel >= TWINKL_CHANNEL_COUNT) {
+		return 0;
+	}
+
+	uint16_t byte = channel / 8;
+	uint8_t bit = channel % 8;
+	
+	if((twinkl_masks[level][byte] & (1 << bit)) != 0) {
+		return 1;
+	}
+	else {
+		return 0;
+	}
+}
+
+
+void twinkl_render(uint8_t *channels) {
+	uint16_t chan;
+	uint8_t level;
+
+	for(chan = 0; chan < TWINKL_CHANNEL_COUNT; chan++) {
+		for(level = 0; level < TWINKL_LEVEL_COUNT; level++) {
+			if(get_mask_bit(level,chan)) {
+				channels[chan] = twinkl_channels[level][chan];
+				break;
+			}
+		}
+	}
+
+	twinkl_has_changed = 0;
+}
+

util.c

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+#include <string.h>
+
+#include "util.h"
+
+void* twinkl_memset(void *ptr, int value, size_t num) {
+	return memset(ptr, value, num);
+}
+
+void* twinkl_memcpy(void *destination, const void *source, size_t num) {
+	return memcpy(destination, source, num);
+}