1 /*
2 * Oh, it's a waste of space, but oh-so-yummy for debugging. It's just
3 * initialization code anyway, so it doesn't take up space when we're
4 * actually running. This version of printf() does not include 64-bit
5 * support. "Live with it."
6 *
7 * Most of this code was shamelessly snarfed from the Linux kernel, then
8 * modified. It's therefore GPL.
9 *
10 * printf() isn't actually needed to build syslinux.com, but during
11 * debugging it's handy.
12 */
13
14 #include <stdarg.h>
15 #include <stdio.h>
16 #include "mystuff.h"
17
strnlen(const char * s,int maxlen)18 static int strnlen(const char *s, int maxlen)
19 {
20 const char *es = s;
21 while (*es && maxlen) {
22 es++;
23 maxlen--;
24 }
25
26 return (es - s);
27 }
28
29 #define ZEROPAD 1 /* pad with zero */
30 #define SIGN 2 /* unsigned/signed long */
31 #define PLUS 4 /* show plus */
32 #define SPACE 8 /* space if plus */
33 #define LEFT 16 /* left justified */
34 #define SPECIAL 32 /* 0x */
35 #define LARGE 64 /* use 'ABCDEF' instead of 'abcdef' */
36
37 #define do_div(n,base) ({ \
38 int __res; \
39 __res = ((unsigned long) n) % (unsigned) base; \
40 n = ((unsigned long) n) / (unsigned) base; \
41 __res; })
42
number(char * str,long num,int base,int size,int precision,int type)43 static char *number(char *str, long num, int base, int size, int precision,
44 int type)
45 {
46 char c, sign, tmp[66];
47 const char *digits = "0123456789abcdefghijklmnopqrstuvwxyz";
48 int i;
49
50 if (type & LARGE)
51 digits = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
52 if (type & LEFT)
53 type &= ~ZEROPAD;
54 if (base < 2 || base > 36)
55 return 0;
56 c = (type & ZEROPAD) ? '0' : ' ';
57 sign = 0;
58 if (type & SIGN) {
59 if (num < 0) {
60 sign = '-';
61 num = -num;
62 size--;
63 } else if (type & PLUS) {
64 sign = '+';
65 size--;
66 } else if (type & SPACE) {
67 sign = ' ';
68 size--;
69 }
70 }
71 if (type & SPECIAL) {
72 if (base == 16)
73 size -= 2;
74 else if (base == 8)
75 size--;
76 }
77 i = 0;
78 if (num == 0)
79 tmp[i++] = '0';
80 else
81 while (num != 0)
82 tmp[i++] = digits[do_div(num, base)];
83 if (i > precision)
84 precision = i;
85 size -= precision;
86 if (!(type & (ZEROPAD + LEFT)))
87 while (size-- > 0)
88 *str++ = ' ';
89 if (sign)
90 *str++ = sign;
91 if (type & SPECIAL) {
92 if (base == 8)
93 *str++ = '0';
94 else if (base == 16) {
95 *str++ = '0';
96 *str++ = digits[33];
97 }
98 }
99 if (!(type & LEFT))
100 while (size-- > 0)
101 *str++ = c;
102 while (i < precision--)
103 *str++ = '0';
104 while (i-- > 0)
105 *str++ = tmp[i];
106 while (size-- > 0)
107 *str++ = ' ';
108 return str;
109 }
110
111 /* Forward decl. needed for IP address printing stuff... */
112 int sprintf(char *buf, const char *fmt, ...);
113
vsprintf(char * buf,const char * fmt,va_list args)114 int vsprintf(char *buf, const char *fmt, va_list args)
115 {
116 int len;
117 unsigned 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
129 for (str = buf; *fmt; ++fmt) {
130 if (*fmt != '%') {
131 *str++ = *fmt;
132 continue;
133 }
134
135 /* process flags */
136 flags = 0;
137 repeat:
138 ++fmt; /* this also skips first '%' */
139 switch (*fmt) {
140 case '-':
141 flags |= LEFT;
142 goto repeat;
143 case '+':
144 flags |= PLUS;
145 goto repeat;
146 case ' ':
147 flags |= SPACE;
148 goto repeat;
149 case '#':
150 flags |= SPECIAL;
151 goto repeat;
152 case '0':
153 flags |= ZEROPAD;
154 goto repeat;
155 }
156
157 /* get field width */
158 field_width = -1;
159 if (isdigit(*fmt))
160 field_width = skip_atou(&fmt);
161 else if (*fmt == '*') {
162 ++fmt;
163 /* it's the next argument */
164 field_width = va_arg(args, int);
165 if (field_width < 0) {
166 field_width = -field_width;
167 flags |= LEFT;
168 }
169 }
170
171 /* get the precision */
172 precision = -1;
173 if (*fmt == '.') {
174 ++fmt;
175 if (isdigit(*fmt))
176 precision = skip_atou(&fmt);
177 else if (*fmt == '*') {
178 ++fmt;
179 /* it's the next argument */
180 precision = va_arg(args, int);
181 }
182 if (precision < 0)
183 precision = 0;
184 }
185
186 /* get the conversion qualifier */
187 qualifier = -1;
188 if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L') {
189 qualifier = *fmt;
190 ++fmt;
191 }
192
193 /* default base */
194 base = 10;
195
196 switch (*fmt) {
197 case 'c':
198 if (!(flags & LEFT))
199 while (--field_width > 0)
200 *str++ = ' ';
201 *str++ = (unsigned char)va_arg(args, int);
202 while (--field_width > 0)
203 *str++ = ' ';
204 continue;
205
206 case 's':
207 s = va_arg(args, char *);
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 case 'n':
230 if (qualifier == 'l') {
231 long *ip = va_arg(args, long *);
232 *ip = (str - buf);
233 } else {
234 int *ip = va_arg(args, int *);
235 *ip = (str - buf);
236 }
237 continue;
238
239 case '%':
240 *str++ = '%';
241 continue;
242
243 /* integer number formats - set up the flags and "break" */
244 case 'o':
245 base = 8;
246 break;
247
248 case 'X':
249 flags |= LARGE;
250 case 'x':
251 base = 16;
252 break;
253
254 case 'd':
255 case 'i':
256 flags |= SIGN;
257 case 'u':
258 break;
259
260 default:
261 *str++ = '%';
262 if (*fmt)
263 *str++ = *fmt;
264 else
265 --fmt;
266 continue;
267 }
268 if (qualifier == 'l')
269 num = va_arg(args, unsigned long);
270 else if (qualifier == 'h') {
271 num = (unsigned short)va_arg(args, int);
272 if (flags & SIGN)
273 num = (short)num;
274 } else if (flags & SIGN)
275 num = va_arg(args, int);
276 else
277 num = va_arg(args, unsigned int);
278 str = number(str, num, base, field_width, precision, flags);
279 }
280 *str = '\0';
281 return str - buf;
282 }
283
sprintf(char * buf,const char * fmt,...)284 int sprintf(char *buf, const char *fmt, ...)
285 {
286 va_list args;
287 int i;
288
289 va_start(args, fmt);
290 i = vsprintf(buf, fmt, args);
291 va_end(args);
292 return i;
293 }
294
printf(const char * fmt,...)295 int printf(const char *fmt, ...)
296 {
297 char printf_buf[1024];
298 va_list args;
299 int printed;
300
301 va_start(args, fmt);
302 printed = vsprintf(printf_buf, fmt, args);
303 va_end(args);
304
305 puts(printf_buf);
306
307 return printed;
308 }
309