b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame^] | 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 | |
| 8 | size_t strnlen(const char * s, size_t count) |
| 9 | { |
| 10 | const char *sc; |
| 11 | |
| 12 | for (sc = s; count-- && *sc != '\0'; ++sc) |
| 13 | /* nothing */; |
| 14 | return sc - s; |
| 15 | } |
| 16 | |
| 17 | # define do_div(n, base) ({ \ |
| 18 | unsigned int __base = (base); \ |
| 19 | unsigned int __rem; \ |
| 20 | __rem = ((unsigned long long)(n)) % __base; \ |
| 21 | (n) = ((unsigned long long)(n)) / __base; \ |
| 22 | __rem; \ |
| 23 | }) |
| 24 | |
| 25 | |
| 26 | static int skip_atoi(const char **s) |
| 27 | { |
| 28 | int i, c; |
| 29 | |
| 30 | for (i = 0; '0' <= (c = **s) && c <= '9'; ++*s) |
| 31 | i = i*10 + c - '0'; |
| 32 | return i; |
| 33 | } |
| 34 | |
| 35 | #define ZEROPAD 1 /* pad with zero */ |
| 36 | #define SIGN 2 /* unsigned/signed long */ |
| 37 | #define PLUS 4 /* show plus */ |
| 38 | #define SPACE 8 /* space if plus */ |
| 39 | #define LEFT 16 /* left justified */ |
| 40 | #define SPECIAL 32 /* 0x */ |
| 41 | #define LARGE 64 /* use 'ABCDEF' instead of 'abcdef' */ |
| 42 | |
| 43 | static char * number(char * str, unsigned long long num, int base, int size, int precision, int type) |
| 44 | { |
| 45 | char c,sign,tmp[66]; |
| 46 | const char *digits="0123456789abcdefghijklmnopqrstuvwxyz"; |
| 47 | int i; |
| 48 | |
| 49 | if (type & LARGE) |
| 50 | digits = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"; |
| 51 | if (type & LEFT) |
| 52 | type &= ~ZEROPAD; |
| 53 | if (base < 2 || base > 36) |
| 54 | return 0; |
| 55 | c = (type & ZEROPAD) ? '0' : ' '; |
| 56 | sign = 0; |
| 57 | if (type & SIGN) { |
| 58 | if ((signed long long)num < 0) { |
| 59 | sign = '-'; |
| 60 | num = - (signed long long)num; |
| 61 | size--; |
| 62 | } else if (type & PLUS) { |
| 63 | sign = '+'; |
| 64 | size--; |
| 65 | } else if (type & SPACE) { |
| 66 | sign = ' '; |
| 67 | size--; |
| 68 | } |
| 69 | } |
| 70 | if (type & SPECIAL) { |
| 71 | if (base == 16) |
| 72 | size -= 2; |
| 73 | else if (base == 8) |
| 74 | size--; |
| 75 | } |
| 76 | i = 0; |
| 77 | if (num == 0) |
| 78 | tmp[i++]='0'; |
| 79 | else while (num != 0) { |
| 80 | tmp[i++] = digits[do_div(num, base)]; |
| 81 | } |
| 82 | if (i > precision) |
| 83 | precision = i; |
| 84 | size -= precision; |
| 85 | if (!(type&(ZEROPAD+LEFT))) |
| 86 | while(size-->0) |
| 87 | *str++ = ' '; |
| 88 | if (sign) |
| 89 | *str++ = sign; |
| 90 | if (type & SPECIAL) { |
| 91 | if (base==8) |
| 92 | *str++ = '0'; |
| 93 | else if (base==16) { |
| 94 | *str++ = '0'; |
| 95 | *str++ = digits[33]; |
| 96 | } |
| 97 | } |
| 98 | if (!(type & LEFT)) |
| 99 | while (size-- > 0) |
| 100 | *str++ = c; |
| 101 | while (i < precision--) |
| 102 | *str++ = '0'; |
| 103 | while (i-- > 0) |
| 104 | *str++ = tmp[i]; |
| 105 | while (size-- > 0) |
| 106 | *str++ = ' '; |
| 107 | return str; |
| 108 | } |
| 109 | |
| 110 | int vsprintf(char *buf, const char *fmt, va_list args) |
| 111 | { |
| 112 | int len; |
| 113 | unsigned long long num; |
| 114 | int i, base; |
| 115 | char * str; |
| 116 | const char *s; |
| 117 | |
| 118 | int flags; /* flags to number() */ |
| 119 | |
| 120 | int field_width; /* width of output field */ |
| 121 | int precision; /* min. # of digits for integers; max |
| 122 | number of chars for from string */ |
| 123 | int qualifier; /* 'h', 'l', or 'L' for integer fields */ |
| 124 | /* 'z' support added 23/7/1999 S.H. */ |
| 125 | /* 'z' changed to 'Z' --davidm 1/25/99 */ |
| 126 | |
| 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 '-': flags |= LEFT; goto repeat; |
| 140 | case '+': flags |= PLUS; goto repeat; |
| 141 | case ' ': flags |= SPACE; goto repeat; |
| 142 | case '#': flags |= SPECIAL; goto repeat; |
| 143 | case '0': flags |= ZEROPAD; goto repeat; |
| 144 | } |
| 145 | |
| 146 | /* get field width */ |
| 147 | field_width = -1; |
| 148 | if ('0' <= *fmt && *fmt <= '9') |
| 149 | field_width = skip_atoi(&fmt); |
| 150 | else if (*fmt == '*') { |
| 151 | ++fmt; |
| 152 | /* it's the next argument */ |
| 153 | field_width = va_arg(args, int); |
| 154 | if (field_width < 0) { |
| 155 | field_width = -field_width; |
| 156 | flags |= LEFT; |
| 157 | } |
| 158 | } |
| 159 | |
| 160 | /* get the precision */ |
| 161 | precision = -1; |
| 162 | if (*fmt == '.') { |
| 163 | ++fmt; |
| 164 | if ('0' <= *fmt && *fmt <= '9') |
| 165 | precision = skip_atoi(&fmt); |
| 166 | else if (*fmt == '*') { |
| 167 | ++fmt; |
| 168 | /* it's the next argument */ |
| 169 | precision = va_arg(args, int); |
| 170 | } |
| 171 | if (precision < 0) |
| 172 | precision = 0; |
| 173 | } |
| 174 | |
| 175 | /* get the conversion qualifier */ |
| 176 | qualifier = -1; |
| 177 | if (*fmt == 'l' && *(fmt + 1) == 'l') { |
| 178 | qualifier = 'q'; |
| 179 | fmt += 2; |
| 180 | } else if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' |
| 181 | || *fmt == 'Z') { |
| 182 | qualifier = *fmt; |
| 183 | ++fmt; |
| 184 | } |
| 185 | |
| 186 | /* default base */ |
| 187 | base = 10; |
| 188 | |
| 189 | switch (*fmt) { |
| 190 | case 'c': |
| 191 | if (!(flags & LEFT)) |
| 192 | while (--field_width > 0) |
| 193 | *str++ = ' '; |
| 194 | *str++ = (unsigned char) va_arg(args, int); |
| 195 | while (--field_width > 0) |
| 196 | *str++ = ' '; |
| 197 | continue; |
| 198 | |
| 199 | case 's': |
| 200 | s = va_arg(args, char *); |
| 201 | if (!s) |
| 202 | s = "<NULL>"; |
| 203 | |
| 204 | len = strnlen(s, precision); |
| 205 | |
| 206 | if (!(flags & LEFT)) |
| 207 | while (len < field_width--) |
| 208 | *str++ = ' '; |
| 209 | for (i = 0; i < len; ++i) |
| 210 | *str++ = *s++; |
| 211 | while (len < field_width--) |
| 212 | *str++ = ' '; |
| 213 | continue; |
| 214 | |
| 215 | case 'p': |
| 216 | if (field_width == -1) { |
| 217 | field_width = 2*sizeof(void *); |
| 218 | flags |= ZEROPAD; |
| 219 | } |
| 220 | str = number(str, |
| 221 | (unsigned long) va_arg(args, void *), 16, |
| 222 | field_width, precision, flags); |
| 223 | continue; |
| 224 | |
| 225 | |
| 226 | case 'n': |
| 227 | if (qualifier == 'l') { |
| 228 | long * ip = va_arg(args, long *); |
| 229 | *ip = (str - buf); |
| 230 | } else if (qualifier == 'Z') { |
| 231 | size_t * ip = va_arg(args, size_t *); |
| 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 | if (flags & SIGN) |
| 271 | num = (signed long) num; |
| 272 | } else if (qualifier == 'q') { |
| 273 | num = va_arg(args, unsigned long long); |
| 274 | if (flags & SIGN) |
| 275 | num = (signed long long) num; |
| 276 | } else if (qualifier == 'Z') { |
| 277 | num = va_arg(args, size_t); |
| 278 | } else if (qualifier == 'h') { |
| 279 | num = (unsigned short) va_arg(args, int); |
| 280 | if (flags & SIGN) |
| 281 | num = (signed short) num; |
| 282 | } else { |
| 283 | num = va_arg(args, unsigned int); |
| 284 | if (flags & SIGN) |
| 285 | num = (signed int) num; |
| 286 | } |
| 287 | str = number(str, num, base, field_width, precision, flags); |
| 288 | } |
| 289 | *str = '\0'; |
| 290 | return str-buf; |
| 291 | } |
| 292 | |
| 293 | int sprintf(char * buf, const char *fmt, ...) |
| 294 | { |
| 295 | va_list args; |
| 296 | int i; |
| 297 | |
| 298 | va_start(args, fmt); |
| 299 | i=vsprintf(buf,fmt,args); |
| 300 | va_end(args); |
| 301 | return i; |
| 302 | } |