libansilove

tundra.c (4998B)

---

 /*
  * tundra.c
  * libansilove 1.3.1
  * https://www.ansilove.org
  *
  * Copyright (c) 2011-2022 Stefan Vogt, Brian Cassidy, and Frederic Cambus
  * All rights reserved.
  *
  * libansilove is licensed under the BSD 2-Clause license.
  * See LICENSE file for details.
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
 #include <gd.h>
 #include <stddef.h>
 #include <stdint.h>
 #include <string.h>
 #include "ansilove.h"
 #include "drawchar.h"
 #include "fonts.h"
 #include "output.h"
 
 #define TUNDRA_VERSION 24
 #define TUNDRA_STRING "TUNDRA24"
 
 #define TUNDRA_HEADER_LENGTH 9 /* 8 + 1 */
 
 #define TUNDRA_POSITION 1
 #define TUNDRA_COLOR_FOREGROUND 2
 #define TUNDRA_COLOR_BACKGROUND 4
 #define TUNDRA_COLOR_BOTH 6
 
 int
 ansilove_tundra(struct ansilove_ctx *ctx, struct ansilove_options *options)
 {
 	char tundra_version;
 	int32_t column = 0, row = 1;
 	uint32_t cursor, character, background = 0, foreground = 0;
 	uint32_t width, height;
 	size_t loop = TUNDRA_HEADER_LENGTH;
 	struct fontStruct fontData;
 
 	/* libgd image pointers */
 	gdImagePtr canvas;
 
 	if (ctx == NULL || options == NULL) {
 		if (ctx)
 			ctx->error = ANSILOVE_INVALID_PARAM;
 
 		return -1;
 	}
 
 	if (ctx->length < TUNDRA_HEADER_LENGTH)
 		goto error;
 
 	if (options->bits != 8 && options->bits !=9) {
 		ctx->error = ANSILOVE_RANGE_ERROR;
 		return -1;
 	}
 
 	options->columns = options->columns ? options->columns : 80;
 	int16_t columns = options->columns;
 
 	if (columns < 1 || columns > 4096) {
 		ctx->error = ANSILOVE_RANGE_ERROR;
 		return -1;
 	}
 
 	/* font selection */
 	memset(&fontData, 0, sizeof(struct fontStruct));
 	select_font(&fontData, options->font);
 
 	/* extract tundra header */
 	tundra_version = ctx->buffer[0];
 
 	if (tundra_version != TUNDRA_VERSION ||
 	    strncmp((const char *)ctx->buffer + 1, TUNDRA_STRING, 8))
 		goto error;
 
 	/* read tundra file a first time to find the image size */
 	while (loop < ctx->length) {
 		if (column == columns) {
 			column = 0;
 			row++;
 		}
 
 		cursor = ctx->buffer[loop];
 
 		switch (cursor) {
 		case TUNDRA_POSITION:
 			if (loop + 8 < ctx->length) {
 				row = (ctx->buffer[loop + 1] << 24) +
 				    (ctx->buffer[loop + 2] << 16) +
 				    (ctx->buffer[loop + 3] << 8) +
 				    ctx->buffer[loop + 4];
 
 				column = (ctx->buffer[loop + 5] << 24) +
 				    (ctx->buffer[loop + 6] << 16) +
 				    (ctx->buffer[loop + 7] << 8) +
 				    ctx->buffer[loop + 8];
 
 				loop += 8;
 			} else {
 				goto error;
 			}
 
 			break;
 
 		case TUNDRA_COLOR_FOREGROUND:
 		case TUNDRA_COLOR_BACKGROUND:
 			loop += 5;
 			column++;
 			break;
 
 		case TUNDRA_COLOR_BOTH:
 			loop += 9;
 			column++;
 			break;
 
 		default:
 			column++;
 		}
 
 		loop++;
 	}
 
 	width = columns * options->bits;
 	height = row * fontData.height;
 
 	if (!width || !height)
 		goto error;
 
 	/* allocate buffer image memory */
 	canvas = gdImageCreateTrueColor(width, height);
 
 	if (!canvas) {
 		ctx->error = ANSILOVE_GD_ERROR;
 		return -1;
 	}
 
 	/* process tundra */
 	column = 0;
 	row = 0;
 
 	loop = TUNDRA_HEADER_LENGTH;
 
 	while (loop < ctx->length) {
 		if (column == columns) {
 			column = 0;
 			row++;
 		}
 
 		cursor = character = ctx->buffer[loop];
 
 		switch (cursor) {
 		case TUNDRA_POSITION:
 			if (loop + 8 < ctx->length) {
 				row = (ctx->buffer[loop + 1] << 24) +
 				    (ctx->buffer[loop + 2] << 16) +
 				    (ctx->buffer[loop + 3] << 8) +
 				    ctx->buffer[loop + 4];
 
 				column =
 				    (ctx->buffer[loop + 5] << 24) +
 				    (ctx->buffer[loop + 6] << 16) +
 				    (ctx->buffer[loop + 7] << 8) +
 				    ctx->buffer[loop + 8];
 
 				loop += 8;
 			} else {
 				goto error;
 			}
 
 			break;
 
 		case TUNDRA_COLOR_FOREGROUND:
 			if (loop + 5 < ctx->length) {
 				foreground =
 				    (ctx->buffer[loop + 3] << 16) +
 				    (ctx->buffer[loop + 4] << 8) +
 				    ctx->buffer[loop + 5];
 
 				character = ctx->buffer[loop+1];
 
 				loop += 5;
 			} else {
 				goto error;
 			}
 
 			break;
 
 		case TUNDRA_COLOR_BACKGROUND:
 			if (loop + 5 < ctx->length) {
 				background = (ctx->buffer[loop + 3] << 16) +
 				    (ctx->buffer[loop + 4] << 8) +
 				    ctx->buffer[loop + 5];
 
 				character = ctx->buffer[loop + 1];
 
 				loop += 5;
 			} else {
 				goto error;
 			}
 
 			break;
 
 		case TUNDRA_COLOR_BOTH:
 			if (loop + 9 < ctx->length) {
 				foreground =
 				    (ctx->buffer[loop + 3] << 16) +
 				    (ctx->buffer[loop + 4] << 8) +
 				    ctx->buffer[loop + 5];
 
 				background =
 				    (ctx->buffer[loop + 7] << 16) +
 				    (ctx->buffer[loop + 8] << 8) +
 				    ctx->buffer[loop + 9];
 
 				character = ctx->buffer[loop + 1];
 
 				loop += 9;
 			} else {
 				goto error;
 			}
 
 			break;
 		}
 
 		if (character != TUNDRA_POSITION &&
 		    character != TUNDRA_COLOR_BACKGROUND &&
 		    character != TUNDRA_COLOR_FOREGROUND &&
 		    character != TUNDRA_COLOR_BOTH) {
 			drawchar(canvas, fontData.font_data, options->bits,
 			    fontData.height, column, row, background,
 			    foreground, character);
 
 			column++;
 		}
 
 		loop++;
 	}
 
 	/* create output image */
 	return output(ctx, options, canvas);
 
 error:
 	ctx->error = ANSILOVE_FORMAT_ERROR;
 	return -1;
 }