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
18static const char *programname;
19static const char *filename;
20static const char *logoname = "linux_logo";
21static const char *outputname;
22static 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
30static 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
39struct color {
40	unsigned char red;
41	unsigned char green;
42	unsigned char blue;
43};
44
45static 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
65static int logo_type = LINUX_LOGO_CLUT224;
66static unsigned int logo_width;
67static unsigned int logo_height;
68static struct color **logo_data;
69static struct color logo_clut[MAX_LINUX_LOGO_COLORS];
70static unsigned int logo_clutsize;
71static int is_plain_pbm = 0;
72
73static void die(const char *fmt, ...)
74__attribute__((noreturn)) __attribute((format (printf, 1, 2)));
75static void usage(void) __attribute((noreturn));
76
77
78static 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
114static 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
121static 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
204static inline int is_black(struct color c)
205{
206	return c.red == 0 && c.green == 0 && c.blue == 0;
207}
208
209static inline int is_white(struct color c)
210{
211	return c.red == 255 && c.green == 255 && c.blue == 255;
212}
213
214static inline int is_gray(struct color c)
215{
216	return c.red == c.green && c.red == c.blue;
217}
218
219static 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
224static 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, " *  It was automatically generated from %s\n", filename);
239	fputs(" *\n", out);
240	fprintf(out, " *  Linux logo %s\n", logoname);
241	fputs(" */\n\n", out);
242	fputs("#include <linux/linux_logo.h>\n\n", out);
243	fprintf(out, "static unsigned char %s_data[] __initdata = {\n",
244		logoname);
245}
246
247static void write_footer(void)
248{
249	fputs("\n};\n\n", out);
250	fprintf(out, "const struct linux_logo %s __initconst = {\n", logoname);
251	fprintf(out, "\t.type\t\t= %s,\n", logo_types[logo_type]);
252	fprintf(out, "\t.width\t\t= %d,\n", logo_width);
253	fprintf(out, "\t.height\t\t= %d,\n", logo_height);
254	if (logo_type == LINUX_LOGO_CLUT224) {
255		fprintf(out, "\t.clutsize\t= %d,\n", logo_clutsize);
256		fprintf(out, "\t.clut\t\t= %s_clut,\n", logoname);
257	}
258	fprintf(out, "\t.data\t\t= %s_data\n", logoname);
259	fputs("};\n\n", out);
260
261	/* close logo file */
262	if (outputname)
263		fclose(out);
264}
265
266static int write_hex_cnt;
267
268static void write_hex(unsigned char byte)
269{
270	if (write_hex_cnt % 12)
271		fprintf(out, ", 0x%02x", byte);
272	else if (write_hex_cnt)
273		fprintf(out, ",\n\t0x%02x", byte);
274	else
275		fprintf(out, "\t0x%02x", byte);
276	write_hex_cnt++;
277}
278
279static void write_logo_mono(void)
280{
281	unsigned int i, j;
282	unsigned char val, bit;
283
284	/* validate image */
285	for (i = 0; i < logo_height; i++)
286		for (j = 0; j < logo_width; j++)
287			if (!is_black(logo_data[i][j]) && !is_white(logo_data[i][j]))
288				die("Image must be monochrome\n");
289
290	/* write file header */
291	write_header();
292
293	/* write logo data */
294	for (i = 0; i < logo_height; i++) {
295		for (j = 0; j < logo_width;) {
296			for (val = 0, bit = 0x80; bit && j < logo_width; j++, bit >>= 1)
297				if (logo_data[i][j].red)
298					val |= bit;
299			write_hex(val);
300		}
301	}
302
303	/* write logo structure and file footer */
304	write_footer();
305}
306
307static void write_logo_vga16(void)
308{
309	unsigned int i, j, k;
310	unsigned char val;
311
312	/* validate image */
313	for (i = 0; i < logo_height; i++)
314		for (j = 0; j < logo_width; j++) {
315			for (k = 0; k < 16; k++)
316				if (is_equal(logo_data[i][j], clut_vga16[k]))
317					break;
318			if (k == 16)
319				die("Image must use the 16 console colors only\n"
320				    "Use ppmquant(1) -map clut_vga16.ppm to reduce the number "
321				    "of colors\n");
322		}
323
324	/* write file header */
325	write_header();
326
327	/* write logo data */
328	for (i = 0; i < logo_height; i++)
329		for (j = 0; j < logo_width; j++) {
330			for (k = 0; k < 16; k++)
331				if (is_equal(logo_data[i][j], clut_vga16[k]))
332					break;
333			val = k<<4;
334			if (++j < logo_width) {
335				for (k = 0; k < 16; k++)
336					if (is_equal(logo_data[i][j], clut_vga16[k]))
337						break;
338				val |= k;
339			}
340			write_hex(val);
341		}
342
343	/* write logo structure and file footer */
344	write_footer();
345}
346
347static void write_logo_clut224(void)
348{
349	unsigned int i, j, k;
350
351	/* validate image */
352	for (i = 0; i < logo_height; i++)
353		for (j = 0; j < logo_width; j++) {
354			for (k = 0; k < logo_clutsize; k++)
355				if (is_equal(logo_data[i][j], logo_clut[k]))
356					break;
357			if (k == logo_clutsize) {
358				if (logo_clutsize == MAX_LINUX_LOGO_COLORS)
359					die("Image has more than %d colors\n"
360					    "Use ppmquant(1) to reduce the number of colors\n",
361					    MAX_LINUX_LOGO_COLORS);
362				logo_clut[logo_clutsize++] = logo_data[i][j];
363			}
364		}
365
366	/* write file header */
367	write_header();
368
369	/* write logo data */
370	for (i = 0; i < logo_height; i++)
371		for (j = 0; j < logo_width; j++) {
372			for (k = 0; k < logo_clutsize; k++)
373				if (is_equal(logo_data[i][j], logo_clut[k]))
374					break;
375			write_hex(k+32);
376		}
377	fputs("\n};\n\n", out);
378
379	/* write logo clut */
380	fprintf(out, "static unsigned char %s_clut[] __initdata = {\n",
381		logoname);
382	write_hex_cnt = 0;
383	for (i = 0; i < logo_clutsize; i++) {
384		write_hex(logo_clut[i].red);
385		write_hex(logo_clut[i].green);
386		write_hex(logo_clut[i].blue);
387	}
388
389	/* write logo structure and file footer */
390	write_footer();
391}
392
393static void write_logo_gray256(void)
394{
395	unsigned int i, j;
396
397	/* validate image */
398	for (i = 0; i < logo_height; i++)
399		for (j = 0; j < logo_width; j++)
400			if (!is_gray(logo_data[i][j]))
401				die("Image must be grayscale\n");
402
403	/* write file header */
404	write_header();
405
406	/* write logo data */
407	for (i = 0; i < logo_height; i++)
408		for (j = 0; j < logo_width; j++)
409			write_hex(logo_data[i][j].red);
410
411	/* write logo structure and file footer */
412	write_footer();
413}
414
415static void die(const char *fmt, ...)
416{
417	va_list ap;
418
419	va_start(ap, fmt);
420	vfprintf(stderr, fmt, ap);
421	va_end(ap);
422
423	exit(1);
424}
425
426static void usage(void)
427{
428	die("\n"
429	"Usage: %s [options] <filename>\n"
430	"\n"
431	"Valid options:\n"
432	"	-h		  : display this usage information\n"
433	"	-n <name>   : specify logo name (default: linux_logo)\n"
434	"	-o <output> : output to file <output> instead of stdout\n"
435	"	-t <type>   : specify logo type, one of\n"
436	"					  mono	: monochrome black/white\n"
437	"					  vga16   : 16 colors VGA text palette\n"
438	"					  clut224 : 224 colors (default)\n"
439	"					  gray256 : 256 levels grayscale\n"
440	"\n", programname);
441}
442
443int main(int argc, char *argv[])
444{
445	int opt;
446
447	programname = argv[0];
448
449	opterr = 0;
450	while (1) {
451		opt = getopt(argc, argv, "hn:o:t:");
452		if (opt == -1)
453			break;
454
455		switch (opt) {
456		case 'h':
457			usage();
458			break;
459
460		case 'n':
461			logoname = optarg;
462			break;
463
464		case 'o':
465			outputname = optarg;
466			break;
467
468		case 't':
469			if (!strcmp(optarg, "mono"))
470				logo_type = LINUX_LOGO_MONO;
471			else if (!strcmp(optarg, "vga16"))
472				logo_type = LINUX_LOGO_VGA16;
473			else if (!strcmp(optarg, "clut224"))
474				logo_type = LINUX_LOGO_CLUT224;
475			else if (!strcmp(optarg, "gray256"))
476				logo_type = LINUX_LOGO_GRAY256;
477			else
478				usage();
479			break;
480
481		default:
482			usage();
483			break;
484		}
485	}
486	if (optind != argc-1)
487		usage();
488
489	filename = argv[optind];
490
491	read_image();
492	switch (logo_type) {
493	case LINUX_LOGO_MONO:
494		write_logo_mono();
495		break;
496
497	case LINUX_LOGO_VGA16:
498		write_logo_vga16();
499		break;
500
501	case LINUX_LOGO_CLUT224:
502		write_logo_clut224();
503		break;
504
505	case LINUX_LOGO_GRAY256:
506		write_logo_gray256();
507		break;
508	}
509	exit(0);
510}
511