xref: /linux/arch/alpha/boot/stdio.c (revision fd639726bf15fca8ee1a00dce8e0096d0ad9bd18)
1 /*
2  * Copyright (C) Paul Mackerras 1997.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * as published by the Free Software Foundation; either version
7  * 2 of the License, or (at your option) any later version.
8  */
9 #include <stdarg.h>
10 #include <stddef.h>
11 
12 size_t strnlen(const char * s, size_t count)
13 {
14 	const char *sc;
15 
16 	for (sc = s; count-- && *sc != '\0'; ++sc)
17 		/* nothing */;
18 	return sc - s;
19 }
20 
21 # define do_div(n, base) ({						\
22 	unsigned int __base = (base);					\
23 	unsigned int __rem;						\
24 	__rem = ((unsigned long long)(n)) % __base;			\
25 	(n) = ((unsigned long long)(n)) / __base;			\
26 	__rem;								\
27 })
28 
29 
30 static int skip_atoi(const char **s)
31 {
32 	int i, c;
33 
34 	for (i = 0; '0' <= (c = **s) && c <= '9'; ++*s)
35 		i = i*10 + c - '0';
36 	return i;
37 }
38 
39 #define ZEROPAD	1		/* pad with zero */
40 #define SIGN	2		/* unsigned/signed long */
41 #define PLUS	4		/* show plus */
42 #define SPACE	8		/* space if plus */
43 #define LEFT	16		/* left justified */
44 #define SPECIAL	32		/* 0x */
45 #define LARGE	64		/* use 'ABCDEF' instead of 'abcdef' */
46 
47 static char * number(char * str, unsigned long long num, int base, int size, int precision, int type)
48 {
49 	char c,sign,tmp[66];
50 	const char *digits="0123456789abcdefghijklmnopqrstuvwxyz";
51 	int i;
52 
53 	if (type & LARGE)
54 		digits = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
55 	if (type & LEFT)
56 		type &= ~ZEROPAD;
57 	if (base < 2 || base > 36)
58 		return 0;
59 	c = (type & ZEROPAD) ? '0' : ' ';
60 	sign = 0;
61 	if (type & SIGN) {
62 		if ((signed long long)num < 0) {
63 			sign = '-';
64 			num = - (signed long long)num;
65 			size--;
66 		} else if (type & PLUS) {
67 			sign = '+';
68 			size--;
69 		} else if (type & SPACE) {
70 			sign = ' ';
71 			size--;
72 		}
73 	}
74 	if (type & SPECIAL) {
75 		if (base == 16)
76 			size -= 2;
77 		else if (base == 8)
78 			size--;
79 	}
80 	i = 0;
81 	if (num == 0)
82 		tmp[i++]='0';
83 	else while (num != 0) {
84 		tmp[i++] = digits[do_div(num, base)];
85 	}
86 	if (i > precision)
87 		precision = i;
88 	size -= precision;
89 	if (!(type&(ZEROPAD+LEFT)))
90 		while(size-->0)
91 			*str++ = ' ';
92 	if (sign)
93 		*str++ = sign;
94 	if (type & SPECIAL) {
95 		if (base==8)
96 			*str++ = '0';
97 		else if (base==16) {
98 			*str++ = '0';
99 			*str++ = digits[33];
100 		}
101 	}
102 	if (!(type & LEFT))
103 		while (size-- > 0)
104 			*str++ = c;
105 	while (i < precision--)
106 		*str++ = '0';
107 	while (i-- > 0)
108 		*str++ = tmp[i];
109 	while (size-- > 0)
110 		*str++ = ' ';
111 	return str;
112 }
113 
114 int vsprintf(char *buf, const char *fmt, va_list args)
115 {
116 	int len;
117 	unsigned long long num;
118 	int i, base;
119 	char * str;
120 	const char *s;
121 
122 	int flags;		/* flags to number() */
123 
124 	int field_width;	/* width of output field */
125 	int precision;		/* min. # of digits for integers; max
126 				   number of chars for from string */
127 	int qualifier;		/* 'h', 'l', or 'L' for integer fields */
128 	                        /* 'z' support added 23/7/1999 S.H.    */
129 				/* 'z' changed to 'Z' --davidm 1/25/99 */
130 
131 
132 	for (str=buf ; *fmt ; ++fmt) {
133 		if (*fmt != '%') {
134 			*str++ = *fmt;
135 			continue;
136 		}
137 
138 		/* process flags */
139 		flags = 0;
140 		repeat:
141 			++fmt;		/* this also skips first '%' */
142 			switch (*fmt) {
143 				case '-': flags |= LEFT; goto repeat;
144 				case '+': flags |= PLUS; goto repeat;
145 				case ' ': flags |= SPACE; goto repeat;
146 				case '#': flags |= SPECIAL; goto repeat;
147 				case '0': flags |= ZEROPAD; goto repeat;
148 				}
149 
150 		/* get field width */
151 		field_width = -1;
152 		if ('0' <= *fmt && *fmt <= '9')
153 			field_width = skip_atoi(&fmt);
154 		else if (*fmt == '*') {
155 			++fmt;
156 			/* it's the next argument */
157 			field_width = va_arg(args, int);
158 			if (field_width < 0) {
159 				field_width = -field_width;
160 				flags |= LEFT;
161 			}
162 		}
163 
164 		/* get the precision */
165 		precision = -1;
166 		if (*fmt == '.') {
167 			++fmt;
168 			if ('0' <= *fmt && *fmt <= '9')
169 				precision = skip_atoi(&fmt);
170 			else if (*fmt == '*') {
171 				++fmt;
172 				/* it's the next argument */
173 				precision = va_arg(args, int);
174 			}
175 			if (precision < 0)
176 				precision = 0;
177 		}
178 
179 		/* get the conversion qualifier */
180 		qualifier = -1;
181 		if (*fmt == 'l' && *(fmt + 1) == 'l') {
182 			qualifier = 'q';
183 			fmt += 2;
184 		} else if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L'
185 			|| *fmt == 'Z') {
186 			qualifier = *fmt;
187 			++fmt;
188 		}
189 
190 		/* default base */
191 		base = 10;
192 
193 		switch (*fmt) {
194 		case 'c':
195 			if (!(flags & LEFT))
196 				while (--field_width > 0)
197 					*str++ = ' ';
198 			*str++ = (unsigned char) va_arg(args, int);
199 			while (--field_width > 0)
200 				*str++ = ' ';
201 			continue;
202 
203 		case 's':
204 			s = va_arg(args, char *);
205 			if (!s)
206 				s = "<NULL>";
207 
208 			len = strnlen(s, precision);
209 
210 			if (!(flags & LEFT))
211 				while (len < field_width--)
212 					*str++ = ' ';
213 			for (i = 0; i < len; ++i)
214 				*str++ = *s++;
215 			while (len < field_width--)
216 				*str++ = ' ';
217 			continue;
218 
219 		case 'p':
220 			if (field_width == -1) {
221 				field_width = 2*sizeof(void *);
222 				flags |= ZEROPAD;
223 			}
224 			str = number(str,
225 				(unsigned long) va_arg(args, void *), 16,
226 				field_width, precision, flags);
227 			continue;
228 
229 
230 		case 'n':
231 			if (qualifier == 'l') {
232 				long * ip = va_arg(args, long *);
233 				*ip = (str - buf);
234 			} else if (qualifier == 'Z') {
235 				size_t * ip = va_arg(args, size_t *);
236 				*ip = (str - buf);
237 			} else {
238 				int * ip = va_arg(args, int *);
239 				*ip = (str - buf);
240 			}
241 			continue;
242 
243 		case '%':
244 			*str++ = '%';
245 			continue;
246 
247 		/* integer number formats - set up the flags and "break" */
248 		case 'o':
249 			base = 8;
250 			break;
251 
252 		case 'X':
253 			flags |= LARGE;
254 		case 'x':
255 			base = 16;
256 			break;
257 
258 		case 'd':
259 		case 'i':
260 			flags |= SIGN;
261 		case 'u':
262 			break;
263 
264 		default:
265 			*str++ = '%';
266 			if (*fmt)
267 				*str++ = *fmt;
268 			else
269 				--fmt;
270 			continue;
271 		}
272 		if (qualifier == 'l') {
273 			num = va_arg(args, unsigned long);
274 			if (flags & SIGN)
275 				num = (signed long) num;
276 		} else if (qualifier == 'q') {
277 			num = va_arg(args, unsigned long long);
278 			if (flags & SIGN)
279 				num = (signed long long) num;
280 		} else if (qualifier == 'Z') {
281 			num = va_arg(args, size_t);
282 		} else if (qualifier == 'h') {
283 			num = (unsigned short) va_arg(args, int);
284 			if (flags & SIGN)
285 				num = (signed short) num;
286 		} else {
287 			num = va_arg(args, unsigned int);
288 			if (flags & SIGN)
289 				num = (signed int) num;
290 		}
291 		str = number(str, num, base, field_width, precision, flags);
292 	}
293 	*str = '\0';
294 	return str-buf;
295 }
296 
297 int sprintf(char * buf, const char *fmt, ...)
298 {
299 	va_list args;
300 	int i;
301 
302 	va_start(args, fmt);
303 	i=vsprintf(buf,fmt,args);
304 	va_end(args);
305 	return i;
306 }
307