1 // SPDX-License-Identifier: GPL-2.0-only 2 /* -*- linux-c -*- ------------------------------------------------------- * 3 * 4 * Copyright (C) 1991, 1992 Linus Torvalds 5 * Copyright 2007 rPath, Inc. - All Rights Reserved 6 * 7 * ----------------------------------------------------------------------- */ 8 9 /* 10 * Oh, it's a waste of space, but oh-so-yummy for debugging. This 11 * version of printf() does not include 64-bit support. "Live with 12 * it." 13 * 14 */ 15 16 #include "boot.h" 17 18 static int skip_atoi(const char **s) 19 { 20 int i = 0; 21 22 while (isdigit(**s)) 23 i = i * 10 + *((*s)++) - '0'; 24 return i; 25 } 26 27 #define ZEROPAD 1 /* pad with zero */ 28 #define SIGN 2 /* unsigned/signed long */ 29 #define PLUS 4 /* show plus */ 30 #define SPACE 8 /* space if plus */ 31 #define LEFT 16 /* left justified */ 32 #define SMALL 32 /* Must be 32 == 0x20 */ 33 #define SPECIAL 64 /* 0x */ 34 35 #define __do_div(n, base) ({ \ 36 int __res; \ 37 __res = ((unsigned long) n) % (unsigned) base; \ 38 n = ((unsigned long) n) / (unsigned) base; \ 39 __res; }) 40 41 static char *number(char *str, long num, int base, int size, int precision, 42 int type) 43 { 44 /* we are called with base 8, 10 or 16, only, thus don't need "G..." */ 45 static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */ 46 47 char tmp[66]; 48 char c, sign, locase; 49 int i; 50 51 /* locase = 0 or 0x20. ORing digits or letters with 'locase' 52 * produces same digits or (maybe lowercased) letters */ 53 locase = (type & SMALL); 54 if (type & LEFT) 55 type &= ~ZEROPAD; 56 if (base < 2 || base > 16) 57 return NULL; 58 c = (type & ZEROPAD) ? '0' : ' '; 59 sign = 0; 60 if (type & SIGN) { 61 if (num < 0) { 62 sign = '-'; 63 num = -num; 64 size--; 65 } else if (type & PLUS) { 66 sign = '+'; 67 size--; 68 } else if (type & SPACE) { 69 sign = ' '; 70 size--; 71 } 72 } 73 if (type & SPECIAL) { 74 if (base == 16) 75 size -= 2; 76 else if (base == 8) 77 size--; 78 } 79 i = 0; 80 if (num == 0) 81 tmp[i++] = '0'; 82 else 83 while (num != 0) 84 tmp[i++] = (digits[__do_div(num, base)] | locase); 85 if (i > precision) 86 precision = i; 87 size -= precision; 88 if (!(type & (ZEROPAD + LEFT))) 89 while (size-- > 0) 90 *str++ = ' '; 91 if (sign) 92 *str++ = sign; 93 if (type & SPECIAL) { 94 if (base == 8) 95 *str++ = '0'; 96 else if (base == 16) { 97 *str++ = '0'; 98 *str++ = ('X' | locase); 99 } 100 } 101 if (!(type & LEFT)) 102 while (size-- > 0) 103 *str++ = c; 104 while (i < precision--) 105 *str++ = '0'; 106 while (i-- > 0) 107 *str++ = tmp[i]; 108 while (size-- > 0) 109 *str++ = ' '; 110 return str; 111 } 112 113 int vsprintf(char *buf, const char *fmt, va_list args) 114 { 115 int len; 116 unsigned long num; 117 int i, base; 118 char *str; 119 const char *s; 120 121 int flags; /* flags to number() */ 122 123 int field_width; /* width of output field */ 124 int precision; /* min. # of digits for integers; max 125 number of chars for from string */ 126 int qualifier; /* 'h', 'l', or 'L' for integer fields */ 127 128 for (str = buf; *fmt; ++fmt) { 129 if (*fmt != '%') { 130 *str++ = *fmt; 131 continue; 132 } 133 134 /* process flags */ 135 flags = 0; 136 repeat: 137 ++fmt; /* this also skips first '%' */ 138 switch (*fmt) { 139 case '-': 140 flags |= LEFT; 141 goto repeat; 142 case '+': 143 flags |= PLUS; 144 goto repeat; 145 case ' ': 146 flags |= SPACE; 147 goto repeat; 148 case '#': 149 flags |= SPECIAL; 150 goto repeat; 151 case '0': 152 flags |= ZEROPAD; 153 goto repeat; 154 } 155 156 /* get field width */ 157 field_width = -1; 158 if (isdigit(*fmt)) 159 field_width = skip_atoi(&fmt); 160 else if (*fmt == '*') { 161 ++fmt; 162 /* it's the next argument */ 163 field_width = va_arg(args, int); 164 if (field_width < 0) { 165 field_width = -field_width; 166 flags |= LEFT; 167 } 168 } 169 170 /* get the precision */ 171 precision = -1; 172 if (*fmt == '.') { 173 ++fmt; 174 if (isdigit(*fmt)) 175 precision = skip_atoi(&fmt); 176 else if (*fmt == '*') { 177 ++fmt; 178 /* it's the next argument */ 179 precision = va_arg(args, int); 180 } 181 if (precision < 0) 182 precision = 0; 183 } 184 185 /* get the conversion qualifier */ 186 qualifier = -1; 187 if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L') { 188 qualifier = *fmt; 189 ++fmt; 190 } 191 192 /* default base */ 193 base = 10; 194 195 switch (*fmt) { 196 case 'c': 197 if (!(flags & LEFT)) 198 while (--field_width > 0) 199 *str++ = ' '; 200 *str++ = (unsigned char)va_arg(args, int); 201 while (--field_width > 0) 202 *str++ = ' '; 203 continue; 204 205 case 's': 206 s = va_arg(args, char *); 207 len = strnlen(s, precision); 208 209 if (!(flags & LEFT)) 210 while (len < field_width--) 211 *str++ = ' '; 212 for (i = 0; i < len; ++i) 213 *str++ = *s++; 214 while (len < field_width--) 215 *str++ = ' '; 216 continue; 217 218 case 'p': 219 if (field_width == -1) { 220 field_width = 2 * sizeof(void *); 221 flags |= ZEROPAD; 222 } 223 str = number(str, 224 (unsigned long)va_arg(args, void *), 16, 225 field_width, precision, flags); 226 continue; 227 228 case 'n': 229 if (qualifier == 'l') { 230 long *ip = va_arg(args, long *); 231 *ip = (str - buf); 232 } else { 233 int *ip = va_arg(args, int *); 234 *ip = (str - buf); 235 } 236 continue; 237 238 case '%': 239 *str++ = '%'; 240 continue; 241 242 /* integer number formats - set up the flags and "break" */ 243 case 'o': 244 base = 8; 245 break; 246 247 case 'x': 248 flags |= SMALL; 249 case 'X': 250 base = 16; 251 break; 252 253 case 'd': 254 case 'i': 255 flags |= SIGN; 256 case 'u': 257 break; 258 259 default: 260 *str++ = '%'; 261 if (*fmt) 262 *str++ = *fmt; 263 else 264 --fmt; 265 continue; 266 } 267 if (qualifier == 'l') 268 num = va_arg(args, unsigned long); 269 else if (qualifier == 'h') { 270 num = (unsigned short)va_arg(args, int); 271 if (flags & SIGN) 272 num = (short)num; 273 } else if (flags & SIGN) 274 num = va_arg(args, int); 275 else 276 num = va_arg(args, unsigned int); 277 str = number(str, num, base, field_width, precision, flags); 278 } 279 *str = '\0'; 280 return str - buf; 281 } 282 283 int sprintf(char *buf, const char *fmt, ...) 284 { 285 va_list args; 286 int i; 287 288 va_start(args, fmt); 289 i = vsprintf(buf, fmt, args); 290 va_end(args); 291 return i; 292 } 293 294 int printf(const char *fmt, ...) 295 { 296 char printf_buf[1024]; 297 va_list args; 298 int printed; 299 300 va_start(args, fmt); 301 printed = vsprintf(printf_buf, fmt, args); 302 va_end(args); 303 304 puts(printf_buf); 305 306 return printed; 307 } 308