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9#include <stdarg.h>
10#include <stddef.h>
11
12size_t strnlen(const char * s, size_t count)
13{
14 const char *sc;
15
16 for (sc = s; count-- && *sc != '\0'; ++sc)
17 ;
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
30static 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
40#define SIGN 2
41#define PLUS 4
42#define SPACE 8
43#define LEFT 16
44#define SPECIAL 32
45#define LARGE 64
46
47static 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
114int 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;
123
124 int field_width;
125 int precision;
126
127 int qualifier;
128
129
130
131
132 for (str=buf ; *fmt ; ++fmt) {
133 if (*fmt != '%') {
134 *str++ = *fmt;
135 continue;
136 }
137
138
139 flags = 0;
140 repeat:
141 ++fmt;
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
151 field_width = -1;
152 if ('0' <= *fmt && *fmt <= '9')
153 field_width = skip_atoi(&fmt);
154 else if (*fmt == '*') {
155 ++fmt;
156
157 field_width = va_arg(args, int);
158 if (field_width < 0) {
159 field_width = -field_width;
160 flags |= LEFT;
161 }
162 }
163
164
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
173 precision = va_arg(args, int);
174 }
175 if (precision < 0)
176 precision = 0;
177 }
178
179
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
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
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
297int 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
