diff src/edl.c @ 3:bd99b6549eb4

*: expand in readme and rename src/main to src/edl
author Paper <mrpapersonic@gmail.com>
date Sun, 24 Dec 2023 20:22:54 -0500
parents
children c2408abb258a
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line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/edl.c	Sun Dec 24 20:22:54 2023 -0500
@@ -0,0 +1,305 @@
+#include <string.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include "edl.h"
+
+#define strnchr(haystack, needle, length) (char*)memchr(haystack, needle, strnlen(haystack, length))
+
+static uint32_t EDL_internal_crcn32b(const unsigned char* restrict message, size_t length) {
+	uint32_t crc = 0xFFFFFFFF;
+
+	size_t i;
+	for (i = 0; i < length && message[i]; i++) {
+		crc = crc ^ message[i];
+		size_t j;
+		for (j = 0; j < 8; j++)
+			crc = (crc >> 1) ^ (0xEDB88320 & -(crc & 1));
+	}
+
+	return ~crc;
+}
+
+/* This parses the first line of the EDL and
+ * creates an array with CRC32 hashes in
+ * the order of the strings.
+*/
+static uint32_t* EDL_internal_parse_first_line(const char* data, size_t* restrict length) {
+	size_t hashes_size = 32, current_hash = 0;
+	uint32_t* hashes = malloc(hashes_size * sizeof(uint32_t));
+
+	size_t len_until_newline = strchr(data, '\n') - data, i, b;
+	for (i = 0, b = 0; i < len_until_newline; i++, b++) {
+		if (data[i] == ';') {
+			if (current_hash >= hashes_size)
+				hashes = realloc(hashes, (hashes_size *= 2) * sizeof(uint32_t));
+			hashes[current_hash++] = EDL_internal_crcn32b((const unsigned char*)&data[i - b], b);
+			b = -1; // ew
+		}
+	}
+
+	*length = current_hash;
+
+	return hashes;
+}
+
+/* -- Functions to extract different datatypes -- */
+
+static size_t EDL_internal_append_offset(const char* input, size_t offset, size_t length) {
+	size_t s = 0;
+
+	s += strchr(&input[offset + s], ';') - &input[offset];
+	if (s + offset > length)
+		return s;
+
+	s += strspn(&input[offset + s], ";\t ");
+	if (s + offset > length)
+		return s;
+
+	return s;
+}
+
+static size_t EDL_internal_get_int(const char* input, size_t offset, size_t length, int* int_return) {
+	if (offset > length)
+		return 0;
+
+	{
+		char* ptr_return;
+		*int_return = strtol(&input[offset], &ptr_return, 10);
+
+		if (!ptr_return)
+			return 0;
+	}
+
+	return EDL_internal_append_offset(input, offset, length);
+}
+
+static size_t EDL_internal_get_double(const char* input, size_t offset, size_t length, double* double_return) {
+	if (offset > length)
+		return 0;
+
+	{
+		char* ptr_return;
+		*double_return = strtod(&input[offset], &ptr_return);
+
+		if (!ptr_return)
+			return 0;
+	}
+
+	return EDL_internal_append_offset(input, offset, length);
+}
+
+static size_t EDL_internal_get_bool(const char* input, size_t offset, size_t length, bool* bool_return) {
+	if (offset > length)
+		return 0;
+
+	if (strncmp((input + offset), "TRUE", 4))
+		*bool_return = true;
+	else if (strncmp((input + offset), "FALSE", 5))
+		*bool_return = false;
+
+	return EDL_internal_append_offset(input, offset, length);
+}
+
+static size_t EDL_internal_get_media_type(const char* input, size_t offset, size_t length, MediaType* media_return) {
+	if (offset > length)
+		return 0;
+
+	if (strncmp(input + offset, "VIDEO", 5))
+		*media_return = MEDIATYPE_VIDEO;
+	else if (strncmp(input + offset, "AUDIO", 5))
+		*media_return = MEDIATYPE_AUDIO;
+
+	return EDL_internal_append_offset(input, offset, length);
+}
+
+static size_t EDL_internal_get_string(const char* input, size_t offset, size_t length, char** string_return) {
+	/* Windows filenames will *NEVER* include double quotes.
+	   This might break with EDL files created with Reaper on Linux. */
+	if (offset > length)
+		return 0;
+
+	size_t start = strchr(&input[offset], '\"') - &input[offset] + 1;
+	if (start + offset > length)
+		return 0;
+
+	size_t s_length = strchr(&input[offset + start], '\"') - &input[offset] - start;
+	if (start + s_length + offset > length)
+		return 0;
+
+	*string_return = malloc((s_length + 1) * sizeof(char));
+	if (!*string_return)
+		return 0;
+
+	memcpy(*string_return, &input[offset + start], s_length);
+	(*string_return)[s_length] = '\0';
+
+	return EDL_internal_append_offset(input, offset, length);
+}
+
+/* memory management routines */
+
+static int EDL_internal_reallocate(EDL_file* input, size_t new_capacity) {
+	input->arr = realloc(input->arr, new_capacity * sizeof(EDL_line));
+	if (!input->arr)
+		return 0;
+
+	if (new_capacity > input->capacity)
+		memset(input->arr + input->capacity, 0, new_capacity - input->capacity);
+
+	input->capacity = new_capacity;
+
+	return 1;
+}
+
+static int EDL_internal_allocate_memory(EDL_file* input) {
+	return EDL_internal_reallocate(input, input->capacity ? input->capacity * 2 : 16);
+}
+
+static int EDL_internal_shrink_memory_to_fit(EDL_file* input) {
+	return EDL_internal_reallocate(input, input->size);
+}
+
+/* the important function */
+EDL_file EDL_parse(const char* data, size_t length) {
+	EDL_file edl = {0};
+	if (!EDL_internal_allocate_memory(&edl))
+		return edl;
+
+	size_t order_size = 0;
+	uint32_t* order = EDL_internal_parse_first_line(data, &order_size);
+
+	size_t offset = strnchr(data, '\n', length) - data + 1;
+	while ((offset = strnchr(data + offset, '\n', length - offset) - data + 1) < length) {
+		size_t local_offset = offset; // this is so our original offset stays intact
+
+		bool ok = true;
+
+		for (int i = 0; i < order_size; i++) {
+#define ADD_TO_OFFSET(x, a) \
+{ \
+	size_t o = a(data, local_offset, length, &edl.arr[edl.size].x); \
+	if (!o) \
+		ok = false; \
+	local_offset += o; \
+}
+			switch (order[i]) {
+				case 0x1541c503: /* ID */
+					ADD_TO_OFFSET(id, EDL_internal_get_int);
+					break;
+				case 0x4b211812: /* Track */
+					ADD_TO_OFFSET(track, EDL_internal_get_int);
+					break;
+				case 0xbb46516f: /* StartTime */
+					ADD_TO_OFFSET(start_time, EDL_internal_get_double);
+					break;
+				case 0xaeac5df7: /* Length */
+					ADD_TO_OFFSET(length, EDL_internal_get_double);
+					break;
+				case 0x03834606: /* PlayRate */
+					ADD_TO_OFFSET(play_rate, EDL_internal_get_double);
+					break;
+				case 0x0c2083d3: /* Locked */
+					ADD_TO_OFFSET(locked, EDL_internal_get_bool);
+					break;
+				case 0xe60c8b1d: /* Normalized */
+					ADD_TO_OFFSET(normalized, EDL_internal_get_bool);
+					break;
+				case 0xbe5802c9: /* StretchMethod */
+					ADD_TO_OFFSET(stretch_method, EDL_internal_get_int);
+					break;
+				case 0x4ec8be4c: /* Looped */
+					ADD_TO_OFFSET(looped, EDL_internal_get_bool);
+					break;
+				case 0xe6cb84d1: /* OnRuler */
+					ADD_TO_OFFSET(on_ruler, EDL_internal_get_bool);
+					break;
+				case 0x035f84c2: /* MediaType */
+					ADD_TO_OFFSET(media_type, EDL_internal_get_media_type);
+					break;
+				case 0x379d32c5: /* FileName */
+					ADD_TO_OFFSET(filename, EDL_internal_get_string);
+					break;
+				case 0x9f334738: /* Stream */
+					ADD_TO_OFFSET(stream, EDL_internal_get_int);
+					break;
+				case 0x07b4e0e7: /* StreamStart */
+					ADD_TO_OFFSET(stream_start, EDL_internal_get_double);
+					break;
+				case 0x8f16c7b8: /* StreamLength */
+					ADD_TO_OFFSET(stream_length, EDL_internal_get_double);
+					break;
+				case 0xd2edd7e4: /* FadeTimeIn */
+					ADD_TO_OFFSET(fade_time_in, EDL_internal_get_double);
+					break;
+				case 0x792e8c40: /* FadeTimeOut */
+					ADD_TO_OFFSET(fade_time_out, EDL_internal_get_double);
+					break;
+				case 0x98374657: /* SustainGain */
+					ADD_TO_OFFSET(sustain_gain, EDL_internal_get_double);
+					break;
+				case 0x3e998b1f: /* CurveIn */
+					ADD_TO_OFFSET(curve_in, EDL_internal_get_int);
+					break;
+				case 0x82fb09c4: /* GainIn */
+					ADD_TO_OFFSET(gain_in, EDL_internal_get_double);
+					break;
+				case 0x53add388: /* CurveOut */
+					ADD_TO_OFFSET(curve_out, EDL_internal_get_int);
+					break;
+				case 0x4210ba56: /* GainOut */
+					ADD_TO_OFFSET(gain_out, EDL_internal_get_double);
+					break;
+				case 0x89c4df6c: /* Layer */
+					ADD_TO_OFFSET(layer, EDL_internal_get_int);
+					break;
+				case 0xadf2f1a3: /* Color */
+					ADD_TO_OFFSET(color, EDL_internal_get_int);
+					break;
+				case 0xa56b43e1: /* CurveInR */
+					ADD_TO_OFFSET(curve_in_r, EDL_internal_get_int);
+					break;
+				case 0xcb6d715e: /* CurveOutR */
+					ADD_TO_OFFSET(curve_out_r, EDL_internal_get_int);
+					break;
+				case 0x9da1b9ed: /* PlayPitch */
+					ADD_TO_OFFSET(play_pitch, EDL_internal_get_double);
+					break;
+				case 0x2bda6ed4: /* LockPitch */
+					ADD_TO_OFFSET(lock_pitch, EDL_internal_get_bool);
+					break;
+				case 0x3071a4c6: /* FirstChannel */
+					ADD_TO_OFFSET(first_channel, EDL_internal_get_int);
+					break;
+				case 0x7de1bd40: /* Channels */
+					ADD_TO_OFFSET(channels, EDL_internal_get_int);
+					break;
+				default:
+					/* ... what */
+					break;
+			}
+		}
+
+		if (!ok)
+			break;
+
+		if (++edl.size >= edl.capacity)
+			EDL_internal_allocate_memory(&edl);
+	}
+
+	EDL_internal_shrink_memory_to_fit(&edl);
+
+	free(order);
+
+	return edl;
+}
+
+void EDL_free(EDL_file file) {
+	size_t i;
+	for (i = 0; i < file.size; i++) {
+		if (file.arr[i].filename)
+			free(file.arr[i].filename);
+	}
+	free(file.arr);
+}