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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) Paul Mackerras 1997.
4 */
5#include <stdarg.h>
6#include <stddef.h>
7#include "string.h"
8#include "stdio.h"
9#include "ops.h"
10
11size_t strnlen(const char * s, size_t count)
12{
13 const char *sc;
14
15 for (sc = s; count-- && *sc != '\0'; ++sc)
16 /* nothing */;
17 return sc - s;
18}
19
20char *strrchr(const char *s, int c)
21{
22 const char *last = NULL;
23 do {
24 if (*s == (char)c)
25 last = s;
26 } while (*s++);
27 return (char *)last;
28}
29
30#ifdef __powerpc64__
31
32# define do_div(n, base) ({ \
33 unsigned int __base = (base); \
34 unsigned int __rem; \
35 __rem = ((unsigned long long)(n)) % __base; \
36 (n) = ((unsigned long long)(n)) / __base; \
37 __rem; \
38})
39
40#else
41
42extern unsigned int __div64_32(unsigned long long *dividend,
43 unsigned int divisor);
44
45/* The unnecessary pointer compare is there
46 * to check for type safety (n must be 64bit)
47 */
48# define do_div(n,base) ({ \
49 unsigned int __base = (base); \
50 unsigned int __rem; \
51 (void)(((typeof((n)) *)0) == ((unsigned long long *)0)); \
52 if (((n) >> 32) == 0) { \
53 __rem = (unsigned int)(n) % __base; \
54 (n) = (unsigned int)(n) / __base; \
55 } else \
56 __rem = __div64_32(&(n), __base); \
57 __rem; \
58 })
59
60#endif /* __powerpc64__ */
61
62static int skip_atoi(const char **s)
63{
64 int i, c;
65
66 for (i = 0; '0' <= (c = **s) && c <= '9'; ++*s)
67 i = i*10 + c - '0';
68 return i;
69}
70
71#define ZEROPAD 1 /* pad with zero */
72#define SIGN 2 /* unsigned/signed long */
73#define PLUS 4 /* show plus */
74#define SPACE 8 /* space if plus */
75#define LEFT 16 /* left justified */
76#define SPECIAL 32 /* 0x */
77#define LARGE 64 /* use 'ABCDEF' instead of 'abcdef' */
78
79static char * number(char * str, unsigned long long num, int base, int size, int precision, int type)
80{
81 char c,sign,tmp[66];
82 const char *digits="0123456789abcdefghijklmnopqrstuvwxyz";
83 int i;
84
85 if (type & LARGE)
86 digits = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
87 if (type & LEFT)
88 type &= ~ZEROPAD;
89 if (base < 2 || base > 36)
90 return 0;
91 c = (type & ZEROPAD) ? '0' : ' ';
92 sign = 0;
93 if (type & SIGN) {
94 if ((signed long long)num < 0) {
95 sign = '-';
96 num = - (signed long long)num;
97 size--;
98 } else if (type & PLUS) {
99 sign = '+';
100 size--;
101 } else if (type & SPACE) {
102 sign = ' ';
103 size--;
104 }
105 }
106 if (type & SPECIAL) {
107 if (base == 16)
108 size -= 2;
109 else if (base == 8)
110 size--;
111 }
112 i = 0;
113 if (num == 0)
114 tmp[i++]='0';
115 else while (num != 0) {
116 tmp[i++] = digits[do_div(num, base)];
117 }
118 if (i > precision)
119 precision = i;
120 size -= precision;
121 if (!(type&(ZEROPAD+LEFT)))
122 while(size-->0)
123 *str++ = ' ';
124 if (sign)
125 *str++ = sign;
126 if (type & SPECIAL) {
127 if (base==8)
128 *str++ = '0';
129 else if (base==16) {
130 *str++ = '0';
131 *str++ = digits[33];
132 }
133 }
134 if (!(type & LEFT))
135 while (size-- > 0)
136 *str++ = c;
137 while (i < precision--)
138 *str++ = '0';
139 while (i-- > 0)
140 *str++ = tmp[i];
141 while (size-- > 0)
142 *str++ = ' ';
143 return str;
144}
145
146int vsprintf(char *buf, const char *fmt, va_list args)
147{
148 int len;
149 unsigned long long num;
150 int i, base;
151 char * str;
152 const char *s;
153
154 int flags; /* flags to number() */
155
156 int field_width; /* width of output field */
157 int precision; /* min. # of digits for integers; max
158 number of chars for from string */
159 int qualifier; /* 'h', 'l', or 'L' for integer fields */
160 /* 'z' support added 23/7/1999 S.H. */
161 /* 'z' changed to 'Z' --davidm 1/25/99 */
162
163
164 for (str=buf ; *fmt ; ++fmt) {
165 if (*fmt != '%') {
166 *str++ = *fmt;
167 continue;
168 }
169
170 /* process flags */
171 flags = 0;
172 repeat:
173 ++fmt; /* this also skips first '%' */
174 switch (*fmt) {
175 case '-': flags |= LEFT; goto repeat;
176 case '+': flags |= PLUS; goto repeat;
177 case ' ': flags |= SPACE; goto repeat;
178 case '#': flags |= SPECIAL; goto repeat;
179 case '0': flags |= ZEROPAD; goto repeat;
180 }
181
182 /* get field width */
183 field_width = -1;
184 if ('0' <= *fmt && *fmt <= '9')
185 field_width = skip_atoi(&fmt);
186 else if (*fmt == '*') {
187 ++fmt;
188 /* it's the next argument */
189 field_width = va_arg(args, int);
190 if (field_width < 0) {
191 field_width = -field_width;
192 flags |= LEFT;
193 }
194 }
195
196 /* get the precision */
197 precision = -1;
198 if (*fmt == '.') {
199 ++fmt;
200 if ('0' <= *fmt && *fmt <= '9')
201 precision = skip_atoi(&fmt);
202 else if (*fmt == '*') {
203 ++fmt;
204 /* it's the next argument */
205 precision = va_arg(args, int);
206 }
207 if (precision < 0)
208 precision = 0;
209 }
210
211 /* get the conversion qualifier */
212 qualifier = -1;
213 if (*fmt == 'l' && *(fmt + 1) == 'l') {
214 qualifier = 'q';
215 fmt += 2;
216 } else if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L'
217 || *fmt == 'Z') {
218 qualifier = *fmt;
219 ++fmt;
220 }
221
222 /* default base */
223 base = 10;
224
225 switch (*fmt) {
226 case 'c':
227 if (!(flags & LEFT))
228 while (--field_width > 0)
229 *str++ = ' ';
230 *str++ = (unsigned char) va_arg(args, int);
231 while (--field_width > 0)
232 *str++ = ' ';
233 continue;
234
235 case 's':
236 s = va_arg(args, char *);
237 if (!s)
238 s = "<NULL>";
239
240 len = strnlen(s, precision);
241
242 if (!(flags & LEFT))
243 while (len < field_width--)
244 *str++ = ' ';
245 for (i = 0; i < len; ++i)
246 *str++ = *s++;
247 while (len < field_width--)
248 *str++ = ' ';
249 continue;
250
251 case 'p':
252 if (field_width == -1) {
253 field_width = 2*sizeof(void *);
254 flags |= ZEROPAD;
255 }
256 str = number(str,
257 (unsigned long) va_arg(args, void *), 16,
258 field_width, precision, flags);
259 continue;
260
261
262 case 'n':
263 if (qualifier == 'l') {
264 long * ip = va_arg(args, long *);
265 *ip = (str - buf);
266 } else if (qualifier == 'Z') {
267 size_t * ip = va_arg(args, size_t *);
268 *ip = (str - buf);
269 } else {
270 int * ip = va_arg(args, int *);
271 *ip = (str - buf);
272 }
273 continue;
274
275 case '%':
276 *str++ = '%';
277 continue;
278
279 /* integer number formats - set up the flags and "break" */
280 case 'o':
281 base = 8;
282 break;
283
284 case 'X':
285 flags |= LARGE;
286 case 'x':
287 base = 16;
288 break;
289
290 case 'd':
291 case 'i':
292 flags |= SIGN;
293 case 'u':
294 break;
295
296 default:
297 *str++ = '%';
298 if (*fmt)
299 *str++ = *fmt;
300 else
301 --fmt;
302 continue;
303 }
304 if (qualifier == 'l') {
305 num = va_arg(args, unsigned long);
306 if (flags & SIGN)
307 num = (signed long) num;
308 } else if (qualifier == 'q') {
309 num = va_arg(args, unsigned long long);
310 if (flags & SIGN)
311 num = (signed long long) num;
312 } else if (qualifier == 'Z') {
313 num = va_arg(args, size_t);
314 } else if (qualifier == 'h') {
315 num = (unsigned short) va_arg(args, int);
316 if (flags & SIGN)
317 num = (signed short) num;
318 } else {
319 num = va_arg(args, unsigned int);
320 if (flags & SIGN)
321 num = (signed int) num;
322 }
323 str = number(str, num, base, field_width, precision, flags);
324 }
325 *str = '\0';
326 return str-buf;
327}
328
329static char sprint_buf[1024];
330
331int
332printf(const char *fmt, ...)
333{
334 va_list args;
335 int n;
336
337 va_start(args, fmt);
338 n = vsprintf(sprint_buf, fmt, args);
339 va_end(args);
340 if (console_ops.write)
341 console_ops.write(sprint_buf, n);
342 return n;
343}