lib/libstand/printf.c

   1 /*-
   2  * Copyright (c) 1986, 1988, 1991, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  * (c) UNIX System Laboratories, Inc.
   5  * All or some portions of this file are derived from material licensed
   6  * to the University of California by American Telephone and Telegraph
   7  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
   8  * the permission of UNIX System Laboratories, Inc.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. Neither the name of the University nor the names of its contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  *      @(#)subr_prf.c  8.3 (Berkeley) 1/21/94
  35  * $FreeBSD: src/lib/libstand/printf.c,v 1.14 2010/07/12 15:32:45 jkim Exp $
  36  */
  37
  38 /*
  39  * Standaloneified version of the FreeBSD kernel printf family.
  40  */
  41
  42 #include <sys/types.h>
  43 #include <sys/stdint.h>
  44 #include <limits.h>
  45 #include <string.h>
  46 #include "stand.h"
  47
  48 /*
  49  * Note that stdarg.h and the ANSI style va_start macro is used for both
  50  * ANSI and traditional C compilers.
  51  */
  52 #include <stdarg.h>
  53
  54 struct snprintf_arg {
  55         char    *buf;
  56         size_t  remain;
  57 };
  58
  59 #define MAXNBUF (sizeof(intmax_t) * CHAR_BIT + 1)
  60
  61 static char     *ksprintn (char *buf, uintmax_t num, int base, int *len, int upper);
  62 static int      kvprintf(const char *, void (*)(int, void *), void *, va_list);
  63 static void     putchar_wrapper(int, void *);
  64 static void     snprintf_func(int, void *);
  65
  66 static void
  67 putchar_wrapper(int ch, void *arg __unused)
  68 {
  69         putchar(ch);
  70 }
  71
  72 int
  73 printf(const char *fmt, ...)
  74 {
  75         va_list ap;
  76         int retval;
  77
  78         va_start(ap, fmt);
  79         retval = kvprintf(fmt, putchar_wrapper, NULL, ap);
  80         va_end(ap);
  81         return retval;
  82 }
  83
  84 void
  85 vprintf(const char *fmt, va_list ap)
  86 {
  87
  88         kvprintf(fmt, putchar_wrapper, NULL, ap);
  89 }
  90
  91 int
  92 sprintf(char *buf, const char *cfmt, ...)
  93 {
  94         int retval;
  95         va_list ap;
  96
  97         va_start(ap, cfmt);
  98         retval = kvprintf(cfmt, NULL, buf, ap);
  99         buf[retval] = '\0';
 100         va_end(ap);
 101         return retval;
 102 }
 103
 104 void
 105 vsprintf(char *buf, const char *cfmt, va_list ap)
 106 {
 107         int     retval;
 108
 109         retval = kvprintf(cfmt, NULL, buf, ap);
 110         buf[retval] = '\0';
 111 }
 112
 113 int
 114 snprintf(char *buf, size_t size, const char *cfmt, ...)
 115 {
 116         int retval;
 117         va_list ap;
 118
 119         va_start(ap, cfmt);
 120         retval = vsnprintf(buf, size, cfmt, ap);
 121         __va_end(ap);
 122         return(retval);
 123 }
 124
 125 int
 126 vsnprintf(char *buf, size_t size, const char *cfmt, va_list ap)
 127 {
 128         struct snprintf_arg info;
 129         int retval;
 130
 131         info.buf = buf;
 132         info.remain = size;
 133         retval = kvprintf(cfmt, snprintf_func, &info, ap);
 134         if (info.remain >= 1)
 135                 *info.buf++ = '\0';
 136         return(retval);
 137 }
 138
 139 static void
 140 snprintf_func(int ch, void *arg)
 141 {
 142         struct snprintf_arg * const info = arg;
 143
 144         if (info->remain >= 2) {
 145                 *info->buf++ = ch;
 146                 info->remain--;
 147         }
 148 }
 149
 150 /*
 151  * Put a NUL-terminated ASCII number (base <= 36) in a buffer in reverse
 152  * order; return an optional length and a pointer to the last character
 153  * written in the buffer (i.e., the first character of the string).
 154  * The buffer pointed to by `nbuf' must have length >= MAXNBUF.
 155  */
 156 static char *
 157 ksprintn(char *nbuf, uintmax_t num, int base, int *lenp, int upper)
 158 {
 159         char *p, c;
 160
 161         p = nbuf;
 162         *p = '\0';
 163         do {
 164                 c = hex2ascii(num % base);
 165                 *++p = upper ? toupper(c) : c;
 166         } while (num /= base);
 167         if (lenp)
 168                 *lenp = p - nbuf;
 169         return (p);
 170 }
 171
 172 /*
 173  * Scaled down version of printf(3).
 174  */
 175 static int
 176 kvprintf(char const *fmt, void (*func)(int, void *), void *arg, va_list ap)
 177 {
 178 #define PCHAR(c) {int cc=(c); if (func) (*func)(cc, arg); else *d++ = cc; retval++; }
 179         char nbuf[MAXNBUF];
 180         char *d;
 181         const char *p, *percent;
 182         int ch, n;
 183         uintmax_t num;
 184         int base, lflag, qflag, tmp, width, ladjust, sharpflag, neg, sign, dot;
 185         int cflag, hflag, jflag, tflag, zflag;
 186         int dwidth, upper;
 187         char padc;
 188         int stop = 0, retval = 0;
 189
 190         num = 0;
 191         if (!func)
 192                 d = (char *) arg;
 193         else
 194                 d = NULL;
 195
 196         if (fmt == NULL)
 197                 fmt = "(fmt null)\n";
 198
 199         for (;;) {
 200                 padc = ' ';
 201                 width = 0;
 202                 while ((ch = (u_char)*fmt++) != '%' || stop) {
 203                         if (ch == '\0')
 204                                 return (retval);
 205                         PCHAR(ch);
 206                 }
 207                 percent = fmt - 1;
 208                 qflag = 0; lflag = 0; ladjust = 0; sharpflag = 0; neg = 0;
 209                 sign = 0; dot = 0; dwidth = 0; upper = 0;
 210                 cflag = 0; hflag = 0; jflag = 0; tflag = 0; zflag = 0;
 211
 212 reswitch:       switch (ch = (u_char)*fmt++) {
 213                 case '.':
 214                         dot = 1;
 215                         goto reswitch;
 216                 case '#':
 217                         sharpflag = 1;
 218                         goto reswitch;
 219                 case '+':
 220                         sign = 1;
 221                         goto reswitch;
 222                 case '-':
 223                         ladjust = 1;
 224                         goto reswitch;
 225                 case '%':
 226                         PCHAR(ch);
 227                         break;
 228                 case '*':
 229                         if (!dot) {
 230                                 width = va_arg(ap, int);
 231                                 if (width < 0) {
 232                                         ladjust = !ladjust;
 233                                         width = -width;
 234                                 }
 235                         } else {
 236                                 dwidth = va_arg(ap, int);
 237                         }
 238                         goto reswitch;
 239                 case '0':
 240                         if (!dot) {
 241                                 padc = '0';
 242                                 goto reswitch;
 243                         }
 244                 case '1': case '2': case '3': case '4':
 245                 case '5': case '6': case '7': case '8': case '9':
 246                                 for (n = 0;; ++fmt) {
 247                                         n = n * 10 + ch - '0';
 248                                         ch = *fmt;
 249                                         if (ch < '0' || ch > '9')
 250                                                 break;
 251                                 }
 252                         if (dot)
 253                                 dwidth = n;
 254                         else
 255                                 width = n;
 256                         goto reswitch;
 257                 case 'c':
 258                         PCHAR(va_arg(ap, int));
 259                         break;
 260                 case 'd':
 261                 case 'i':
 262                         base = 10;
 263                         sign = 1;
 264                         goto handle_sign;
 265                 case 'h':
 266                         if (hflag) {
 267                                 hflag = 0;
 268                                 cflag = 1;
 269                         } else
 270                                 hflag = 1;
 271                         goto reswitch;
 272                 case 'j':
 273                         jflag = 1;
 274                         goto reswitch;
 275                 case 'l':
 276                         if (lflag) {
 277                                 lflag = 0;
 278                                 qflag = 1;
 279                         } else
 280                                 lflag = 1;
 281                         goto reswitch;
 282                 case 'n':
 283                         if (jflag)
 284                                 *(va_arg(ap, intmax_t *)) = retval;
 285                         else if (qflag)
 286                                 *(va_arg(ap, quad_t *)) = retval;
 287                         else if (lflag)
 288                                 *(va_arg(ap, long *)) = retval;
 289                         else if (zflag)
 290                                 *(va_arg(ap, size_t *)) = retval;
 291                         else if (hflag)
 292                                 *(va_arg(ap, short *)) = retval;
 293                         else if (cflag)
 294                                 *(va_arg(ap, char *)) = retval;
 295                         else
 296                                 *(va_arg(ap, int *)) = retval;
 297                         break;
 298                 case 'o':
 299                         base = 8;
 300                         goto handle_nosign;
 301                 case 'p':
 302                         base = 16;
 303                         sharpflag = (width == 0);
 304                         sign = 0;
 305                         num = (uintptr_t)va_arg(ap, void *);
 306                         goto number;
 307                 case 'q':
 308                         qflag = 1;
 309                         goto reswitch;
 310                 case 's':
 311                         p = va_arg(ap, char *);
 312                         if (p == NULL)
 313                                 p = "(null)";
 314                         if (!dot)
 315                                 n = strlen (p);
 316                         else
 317                                 for (n = 0; n < dwidth && p[n]; n++)
 318                                         continue;
 319
 320                         width -= n;
 321
 322                         if (!ladjust && width > 0)
 323                                 while (width--)
 324                                         PCHAR(padc);
 325                         while (n--)
 326                                 PCHAR(*p++);
 327                         if (ladjust && width > 0)
 328                                 while (width--)
 329                                         PCHAR(padc);
 330                         break;
 331                 case 't':
 332                         tflag = 1;
 333                         goto reswitch;
 334                 case 'u':
 335                         base = 10;
 336                         goto handle_nosign;
 337                 case 'X':
 338                         upper = 1;
 339                 case 'x':
 340                         base = 16;
 341                         goto handle_nosign;
 342                 case 'z':
 343                         zflag = 1;
 344                         goto reswitch;
 345 handle_nosign:
 346                         sign = 0;
 347                         if (jflag)
 348                                 num = va_arg(ap, uintmax_t);
 349                         else if (qflag)
 350                                 num = va_arg(ap, u_quad_t);
 351                         else if (tflag)
 352                                 num = va_arg(ap, ptrdiff_t);
 353                         else if (lflag)
 354                                 num = va_arg(ap, u_long);
 355                         else if (zflag)
 356                                 num = va_arg(ap, size_t);
 357                         else if (hflag)
 358                                 num = (u_short)va_arg(ap, int);
 359                         else if (cflag)
 360                                 num = (u_char)va_arg(ap, int);
 361                         else
 362                                 num = va_arg(ap, u_int);
 363                         goto number;
 364 handle_sign:
 365                         if (jflag)
 366                                 num = va_arg(ap, intmax_t);
 367                         else if (qflag)
 368                                 num = va_arg(ap, quad_t);
 369                         else if (tflag)
 370                                 num = va_arg(ap, ptrdiff_t);
 371                         else if (lflag)
 372                                 num = va_arg(ap, long);
 373                         else if (zflag)
 374                                 num = va_arg(ap, ssize_t);
 375                         else if (hflag)
 376                                 num = (short)va_arg(ap, int);
 377                         else if (cflag)
 378                                 num = (char)va_arg(ap, int);
 379                         else
 380                                 num = va_arg(ap, int);
 381 number:
 382                         if (sign && (intmax_t)num < 0) {
 383                                 neg = 1;
 384                                 num = -(intmax_t)num;
 385                         }
 386                         p = ksprintn(nbuf, num, base, &n, upper);
 387                         tmp = 0;
 388                         if (sharpflag && num != 0) {
 389                                 if (base == 8)
 390                                         tmp++;
 391                                 else if (base == 16)
 392                                         tmp += 2;
 393                         }
 394                         if (neg)
 395                                 tmp++;
 396
 397                         if (!ladjust && padc == '0')
 398                                 dwidth = width - tmp;
 399                         width -= tmp + imax(dwidth, n);
 400                         dwidth -= n;
 401                         if (!ladjust)
 402                                 while (width-- > 0)
 403                                         PCHAR(' ');
 404                         if (neg)
 405                                 PCHAR('-');
 406                         if (sharpflag && num != 0) {
 407                                 if (base == 8) {
 408                                         PCHAR('0');
 409                                 } else if (base == 16) {
 410                                         PCHAR('0');
 411                                         PCHAR('x');
 412                                 }
 413                         }
 414                         while (dwidth-- > 0)
 415                                 PCHAR('0');
 416
 417                         while (*p)
 418                                 PCHAR(*p--);
 419
 420                         if (ladjust)
 421                                 while (width-- > 0)
 422                                         PCHAR(' ');
 423
 424                         break;
 425                 default:
 426                         while (percent < fmt)
 427                                 PCHAR(*percent++);
 428                         /*
 429                          * Since we ignore an formatting argument it is no
 430                          * longer safe to obey the remaining formatting
 431                          * arguments as the arguments will no longer match
 432                          * the format specs.
 433                          */
 434                         stop = 1;
 435                         break;
 436                 }
 437         }
 438 #undef PCHAR
 439 }