xref: /linux/drivers/video/logo/pnmtologo.c (revision 375c4d1583948cf2439833e4a85d5a0aee853895)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Convert a logo in ASCII PNM format to C source suitable for inclusion in
4  *  the Linux kernel
5  *
6  *  (C) Copyright 2001-2003 by Geert Uytterhoeven <geert@linux-m68k.org>
7  */
8 
9 #include <ctype.h>
10 #include <errno.h>
11 #include <stdarg.h>
12 #include <stdio.h>
13 #include <stdlib.h>
14 #include <string.h>
15 #include <unistd.h>
16 
17 
18 static const char *programname;
19 static const char *filename;
20 static const char *logoname = "linux_logo";
21 static const char *outputname;
22 static FILE *out;
23 
24 
25 #define LINUX_LOGO_MONO		1	/* monochrome black/white */
26 #define LINUX_LOGO_VGA16	2	/* 16 colors VGA text palette */
27 #define LINUX_LOGO_CLUT224	3	/* 224 colors */
28 #define LINUX_LOGO_GRAY256	4	/* 256 levels grayscale */
29 
30 static const char *logo_types[LINUX_LOGO_GRAY256+1] = {
31 	[LINUX_LOGO_MONO] = "LINUX_LOGO_MONO",
32 	[LINUX_LOGO_VGA16] = "LINUX_LOGO_VGA16",
33 	[LINUX_LOGO_CLUT224] = "LINUX_LOGO_CLUT224",
34 	[LINUX_LOGO_GRAY256] = "LINUX_LOGO_GRAY256"
35 };
36 
37 #define MAX_LINUX_LOGO_COLORS	224
38 
39 struct color {
40 	unsigned char red;
41 	unsigned char green;
42 	unsigned char blue;
43 };
44 
45 static const struct color clut_vga16[16] = {
46 	{ 0x00, 0x00, 0x00 },
47 	{ 0x00, 0x00, 0xaa },
48 	{ 0x00, 0xaa, 0x00 },
49 	{ 0x00, 0xaa, 0xaa },
50 	{ 0xaa, 0x00, 0x00 },
51 	{ 0xaa, 0x00, 0xaa },
52 	{ 0xaa, 0x55, 0x00 },
53 	{ 0xaa, 0xaa, 0xaa },
54 	{ 0x55, 0x55, 0x55 },
55 	{ 0x55, 0x55, 0xff },
56 	{ 0x55, 0xff, 0x55 },
57 	{ 0x55, 0xff, 0xff },
58 	{ 0xff, 0x55, 0x55 },
59 	{ 0xff, 0x55, 0xff },
60 	{ 0xff, 0xff, 0x55 },
61 	{ 0xff, 0xff, 0xff },
62 };
63 
64 
65 static int logo_type = LINUX_LOGO_CLUT224;
66 static unsigned int logo_width;
67 static unsigned int logo_height;
68 static struct color **logo_data;
69 static struct color logo_clut[MAX_LINUX_LOGO_COLORS];
70 static unsigned int logo_clutsize;
71 static int is_plain_pbm = 0;
72 
73 static void die(const char *fmt, ...)
74 __attribute__((noreturn)) __attribute((format (printf, 1, 2)));
75 static void usage(void) __attribute((noreturn));
76 
77 
78 static unsigned int get_number(FILE *fp)
79 {
80 	int c, val;
81 
82 	/* Skip leading whitespace */
83 	do {
84 		c = fgetc(fp);
85 		if (c == EOF)
86 			die("%s: end of file\n", filename);
87 		if (c == '#') {
88 			/* Ignore comments 'till end of line */
89 			do {
90 				c = fgetc(fp);
91 				if (c == EOF)
92 					die("%s: end of file\n", filename);
93 			} while (c != '\n');
94 		}
95 	} while (isspace(c));
96 
97 	/* Parse decimal number */
98 	val = 0;
99 	while (isdigit(c)) {
100 		val = 10*val+c-'0';
101 		/* some PBM are 'broken'; GiMP for example exports a PBM without space
102 		 * between the digits. This is Ok cause we know a PBM can only have a '1'
103 		 * or a '0' for the digit.
104 		 */
105 		if (is_plain_pbm)
106 			break;
107 		c = fgetc(fp);
108 		if (c == EOF)
109 			die("%s: end of file\n", filename);
110 	}
111 	return val;
112 }
113 
114 static unsigned int get_number255(FILE *fp, unsigned int maxval)
115 {
116 	unsigned int val = get_number(fp);
117 
118 	return (255*val+maxval/2)/maxval;
119 }
120 
121 static void read_image(void)
122 {
123 	FILE *fp;
124 	unsigned int i, j;
125 	int magic;
126 	unsigned int maxval;
127 
128 	/* open image file */
129 	fp = fopen(filename, "r");
130 	if (!fp)
131 		die("Cannot open file %s: %s\n", filename, strerror(errno));
132 
133 	/* check file type and read file header */
134 	magic = fgetc(fp);
135 	if (magic != 'P')
136 		die("%s is not a PNM file\n", filename);
137 	magic = fgetc(fp);
138 	switch (magic) {
139 	case '1':
140 	case '2':
141 	case '3':
142 		/* Plain PBM/PGM/PPM */
143 		break;
144 
145 	case '4':
146 	case '5':
147 	case '6':
148 		/* Binary PBM/PGM/PPM */
149 		die("%s: Binary PNM is not supported\n"
150 		"Use pnmnoraw(1) to convert it to ASCII PNM\n", filename);
151 
152 	default:
153 		die("%s is not a PNM file\n", filename);
154 	}
155 	logo_width = get_number(fp);
156 	logo_height = get_number(fp);
157 
158 	/* allocate image data */
159 	logo_data = (struct color **)malloc(logo_height*sizeof(struct color *));
160 	if (!logo_data)
161 		die("%s\n", strerror(errno));
162 	for (i = 0; i < logo_height; i++) {
163 		logo_data[i] = malloc(logo_width*sizeof(struct color));
164 	if (!logo_data[i])
165 		die("%s\n", strerror(errno));
166 	}
167 
168 	/* read image data */
169 	switch (magic) {
170 	case '1':
171 		/* Plain PBM */
172 		is_plain_pbm = 1;
173 		for (i = 0; i < logo_height; i++)
174 			for (j = 0; j < logo_width; j++)
175 				logo_data[i][j].red = logo_data[i][j].green =
176 					logo_data[i][j].blue = 255*(1-get_number(fp));
177 		break;
178 
179 	case '2':
180 		/* Plain PGM */
181 		maxval = get_number(fp);
182 		for (i = 0; i < logo_height; i++)
183 			for (j = 0; j < logo_width; j++)
184 				logo_data[i][j].red = logo_data[i][j].green =
185 					logo_data[i][j].blue = get_number255(fp, maxval);
186 		break;
187 
188 	case '3':
189 		/* Plain PPM */
190 		maxval = get_number(fp);
191 		for (i = 0; i < logo_height; i++)
192 			for (j = 0; j < logo_width; j++) {
193 				logo_data[i][j].red = get_number255(fp, maxval);
194 				logo_data[i][j].green = get_number255(fp, maxval);
195 				logo_data[i][j].blue = get_number255(fp, maxval);
196 			}
197 		break;
198 	}
199 
200 	/* close file */
201 	fclose(fp);
202 }
203 
204 static inline int is_black(struct color c)
205 {
206 	return c.red == 0 && c.green == 0 && c.blue == 0;
207 }
208 
209 static inline int is_white(struct color c)
210 {
211 	return c.red == 255 && c.green == 255 && c.blue == 255;
212 }
213 
214 static inline int is_gray(struct color c)
215 {
216 	return c.red == c.green && c.red == c.blue;
217 }
218 
219 static inline int is_equal(struct color c1, struct color c2)
220 {
221 	return c1.red == c2.red && c1.green == c2.green && c1.blue == c2.blue;
222 }
223 
224 static void write_header(void)
225 {
226 	/* open logo file */
227 	if (outputname) {
228 		out = fopen(outputname, "w");
229 		if (!out)
230 			die("Cannot create file %s: %s\n", outputname, strerror(errno));
231 	} else {
232 		out = stdout;
233 	}
234 
235 	fputs("/*\n", out);
236 	fputs(" *  DO NOT EDIT THIS FILE!\n", out);
237 	fputs(" *\n", out);
238 	fprintf(out, " *  Linux logo %s\n", logoname);
239 	fputs(" */\n\n", out);
240 	fputs("#include <linux/linux_logo.h>\n\n", out);
241 	fprintf(out, "static unsigned char %s_data[] __initdata = {\n",
242 		logoname);
243 }
244 
245 static void write_footer(void)
246 {
247 	fputs("\n};\n\n", out);
248 	fprintf(out, "const struct linux_logo %s __initconst = {\n", logoname);
249 	fprintf(out, "\t.type\t\t= %s,\n", logo_types[logo_type]);
250 	fprintf(out, "\t.width\t\t= %u,\n", logo_width);
251 	fprintf(out, "\t.height\t\t= %u,\n", logo_height);
252 	if (logo_type == LINUX_LOGO_CLUT224) {
253 		fprintf(out, "\t.clutsize\t= %u,\n", logo_clutsize);
254 		fprintf(out, "\t.clut\t\t= %s_clut,\n", logoname);
255 	}
256 	fprintf(out, "\t.data\t\t= %s_data\n", logoname);
257 	fputs("};\n\n", out);
258 
259 	/* close logo file */
260 	if (outputname)
261 		fclose(out);
262 }
263 
264 static int write_hex_cnt;
265 
266 static void write_hex(unsigned char byte)
267 {
268 	if (write_hex_cnt % 12)
269 		fprintf(out, ", 0x%02x", byte);
270 	else if (write_hex_cnt)
271 		fprintf(out, ",\n\t0x%02x", byte);
272 	else
273 		fprintf(out, "\t0x%02x", byte);
274 	write_hex_cnt++;
275 }
276 
277 static void write_logo_mono(void)
278 {
279 	unsigned int i, j;
280 	unsigned char val, bit;
281 
282 	/* validate image */
283 	for (i = 0; i < logo_height; i++)
284 		for (j = 0; j < logo_width; j++)
285 			if (!is_black(logo_data[i][j]) && !is_white(logo_data[i][j]))
286 				die("Image must be monochrome\n");
287 
288 	/* write file header */
289 	write_header();
290 
291 	/* write logo data */
292 	for (i = 0; i < logo_height; i++) {
293 		for (j = 0; j < logo_width;) {
294 			for (val = 0, bit = 0x80; bit && j < logo_width; j++, bit >>= 1)
295 				if (logo_data[i][j].red)
296 					val |= bit;
297 			write_hex(val);
298 		}
299 	}
300 
301 	/* write logo structure and file footer */
302 	write_footer();
303 }
304 
305 static void write_logo_vga16(void)
306 {
307 	unsigned int i, j, k;
308 	unsigned char val;
309 
310 	/* validate image */
311 	for (i = 0; i < logo_height; i++)
312 		for (j = 0; j < logo_width; j++) {
313 			for (k = 0; k < 16; k++)
314 				if (is_equal(logo_data[i][j], clut_vga16[k]))
315 					break;
316 			if (k == 16)
317 				die("Image must use the 16 console colors only\n"
318 				    "Use ppmquant(1) -map clut_vga16.ppm to reduce the number "
319 				    "of colors\n");
320 		}
321 
322 	/* write file header */
323 	write_header();
324 
325 	/* write logo data */
326 	for (i = 0; i < logo_height; i++)
327 		for (j = 0; j < logo_width; j++) {
328 			for (k = 0; k < 16; k++)
329 				if (is_equal(logo_data[i][j], clut_vga16[k]))
330 					break;
331 			val = k<<4;
332 			if (++j < logo_width) {
333 				for (k = 0; k < 16; k++)
334 					if (is_equal(logo_data[i][j], clut_vga16[k]))
335 						break;
336 				val |= k;
337 			}
338 			write_hex(val);
339 		}
340 
341 	/* write logo structure and file footer */
342 	write_footer();
343 }
344 
345 static void write_logo_clut224(void)
346 {
347 	unsigned int i, j, k;
348 
349 	/* validate image */
350 	for (i = 0; i < logo_height; i++)
351 		for (j = 0; j < logo_width; j++) {
352 			for (k = 0; k < logo_clutsize; k++)
353 				if (is_equal(logo_data[i][j], logo_clut[k]))
354 					break;
355 			if (k == logo_clutsize) {
356 				if (logo_clutsize == MAX_LINUX_LOGO_COLORS)
357 					die("Image has more than %d colors\n"
358 					    "Use ppmquant(1) to reduce the number of colors\n",
359 					    MAX_LINUX_LOGO_COLORS);
360 				logo_clut[logo_clutsize++] = logo_data[i][j];
361 			}
362 		}
363 
364 	/* write file header */
365 	write_header();
366 
367 	/* write logo data */
368 	for (i = 0; i < logo_height; i++)
369 		for (j = 0; j < logo_width; j++) {
370 			for (k = 0; k < logo_clutsize; k++)
371 				if (is_equal(logo_data[i][j], logo_clut[k]))
372 					break;
373 			write_hex(k+32);
374 		}
375 	fputs("\n};\n\n", out);
376 
377 	/* write logo clut */
378 	fprintf(out, "static unsigned char %s_clut[] __initdata = {\n",
379 		logoname);
380 	write_hex_cnt = 0;
381 	for (i = 0; i < logo_clutsize; i++) {
382 		write_hex(logo_clut[i].red);
383 		write_hex(logo_clut[i].green);
384 		write_hex(logo_clut[i].blue);
385 	}
386 
387 	/* write logo structure and file footer */
388 	write_footer();
389 }
390 
391 static void write_logo_gray256(void)
392 {
393 	unsigned int i, j;
394 
395 	/* validate image */
396 	for (i = 0; i < logo_height; i++)
397 		for (j = 0; j < logo_width; j++)
398 			if (!is_gray(logo_data[i][j]))
399 				die("Image must be grayscale\n");
400 
401 	/* write file header */
402 	write_header();
403 
404 	/* write logo data */
405 	for (i = 0; i < logo_height; i++)
406 		for (j = 0; j < logo_width; j++)
407 			write_hex(logo_data[i][j].red);
408 
409 	/* write logo structure and file footer */
410 	write_footer();
411 }
412 
413 static void die(const char *fmt, ...)
414 {
415 	va_list ap;
416 
417 	va_start(ap, fmt);
418 	vfprintf(stderr, fmt, ap);
419 	va_end(ap);
420 
421 	exit(1);
422 }
423 
424 static void usage(void)
425 {
426 	die("\n"
427 	"Usage: %s [options] <filename>\n"
428 	"\n"
429 	"Valid options:\n"
430 	"	-h		  : display this usage information\n"
431 	"	-n <name>   : specify logo name (default: linux_logo)\n"
432 	"	-o <output> : output to file <output> instead of stdout\n"
433 	"	-t <type>   : specify logo type, one of\n"
434 	"					  mono	: monochrome black/white\n"
435 	"					  vga16   : 16 colors VGA text palette\n"
436 	"					  clut224 : 224 colors (default)\n"
437 	"					  gray256 : 256 levels grayscale\n"
438 	"\n", programname);
439 }
440 
441 int main(int argc, char *argv[])
442 {
443 	int opt;
444 
445 	programname = argv[0];
446 
447 	opterr = 0;
448 	while (1) {
449 		opt = getopt(argc, argv, "hn:o:t:");
450 		if (opt == -1)
451 			break;
452 
453 		switch (opt) {
454 		case 'h':
455 			usage();
456 			break;
457 
458 		case 'n':
459 			logoname = optarg;
460 			break;
461 
462 		case 'o':
463 			outputname = optarg;
464 			break;
465 
466 		case 't':
467 			if (!strcmp(optarg, "mono"))
468 				logo_type = LINUX_LOGO_MONO;
469 			else if (!strcmp(optarg, "vga16"))
470 				logo_type = LINUX_LOGO_VGA16;
471 			else if (!strcmp(optarg, "clut224"))
472 				logo_type = LINUX_LOGO_CLUT224;
473 			else if (!strcmp(optarg, "gray256"))
474 				logo_type = LINUX_LOGO_GRAY256;
475 			else
476 				usage();
477 			break;
478 
479 		default:
480 			usage();
481 			break;
482 		}
483 	}
484 	if (optind != argc-1)
485 		usage();
486 
487 	filename = argv[optind];
488 
489 	read_image();
490 	switch (logo_type) {
491 	case LINUX_LOGO_MONO:
492 		write_logo_mono();
493 		break;
494 
495 	case LINUX_LOGO_VGA16:
496 		write_logo_vga16();
497 		break;
498 
499 	case LINUX_LOGO_CLUT224:
500 		write_logo_clut224();
501 		break;
502 
503 	case LINUX_LOGO_GRAY256:
504 		write_logo_gray256();
505 		break;
506 	}
507 	exit(0);
508 }
509