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 <stddef.h>
  46 #include <string.h>
  47 #include "stand.h"
  48
  49 /*
  50  * Note that stdarg.h and the ANSI style va_start macro is used for both
  51  * ANSI and traditional C compilers.
  52  */
  53 #include <stdarg.h>
  54
  55 struct snprintf_arg {
  56         char    *buf;
  57         size_t  remain;
  58 };
  59
  60 #define MAXNBUF (sizeof(intmax_t) * CHAR_BIT + 1)
  61
  62 static char     *ksprintn (char *buf, uintmax_t num, int base, int *len, int upper);
  63 static int      kvprintf(const char *, void (*)(int, void *), void *, va_list);
  64 static void     putchar_wrapper(int, void *);
  65 static void     snprintf_func(int, void *);
  66
  67 static void
  68 putchar_wrapper(int ch, void *arg __unused)
  69 {
  70         putchar(ch);
  71 }
  72
  73 int
  74 printf(const char *fmt, ...)
  75 {
  76         va_list ap;
  77         int retval;
  78
  79         va_start(ap, fmt);
  80         retval = kvprintf(fmt, putchar_wrapper, NULL, ap);
  81         va_end(ap);
  82         return retval;
  83 }
  84
  85 void
  86 vprintf(const char *fmt, va_list ap)
  87 {
  88
  89         kvprintf(fmt, putchar_wrapper, NULL, ap);
  90 }
  91
  92 int
  93 sprintf(char *buf, const char *cfmt, ...)
  94 {
  95         int retval;
  96         va_list ap;
  97
  98         va_start(ap, cfmt);
  99         retval = kvprintf(cfmt, NULL, buf, ap);
 100         buf[retval] = '\0';
 101         va_end(ap);
 102         return retval;
 103 }
 104
 105 void
 106 vsprintf(char *buf, const char *cfmt, va_list ap)
 107 {
 108         int     retval;
 109
 110         retval = kvprintf(cfmt, NULL, buf, ap);
 111         buf[retval] = '\0';
 112 }
 113
 114 int
 115 snprintf(char *buf, size_t size, const char *cfmt, ...)
 116 {
 117         int retval;
 118         va_list ap;
 119
 120         va_start(ap, cfmt);
 121         retval = vsnprintf(buf, size, cfmt, ap);
 122         __va_end(ap);
 123         return(retval);
 124 }
 125
 126 int
 127 vsnprintf(char *buf, size_t size, const char *cfmt, va_list ap)
 128 {
 129         struct snprintf_arg info;
 130         int retval;
 131
 132         info.buf = buf;
 133         info.remain = size;
 134         retval = kvprintf(cfmt, snprintf_func, &info, ap);
 135         if (info.remain >= 1)
 136                 *info.buf++ = '\0';
 137         return(retval);
 138 }
 139
 140 static void
 141 snprintf_func(int ch, void *arg)
 142 {
 143         struct snprintf_arg * const info = arg;
 144
 145         if (info->remain >= 2) {
 146                 *info->buf++ = ch;
 147                 info->remain--;
 148         }
 149 }
 150
 151 /*
 152  * Put a NUL-terminated ASCII number (base <= 36) in a buffer in reverse
 153  * order; return an optional length and a pointer to the last character
 154  * written in the buffer (i.e., the first character of the string).
 155  * The buffer pointed to by `nbuf' must have length >= MAXNBUF.
 156  */
 157 static char *
 158 ksprintn(char *nbuf, uintmax_t num, int base, int *lenp, int upper)
 159 {
 160         char *p, c;
 161
 162         p = nbuf;
 163         *p = '\0';
 164         do {
 165                 c = hex2ascii(num % base);
 166                 *++p = upper ? toupper(c) : c;
 167         } while (num /= base);
 168         if (lenp)
 169                 *lenp = p - nbuf;
 170         return (p);
 171 }
 172
 173 /*
 174  * Scaled down version of printf(3).
 175  */
 176 static int
 177 kvprintf(char const *fmt, void (*func)(int, void *), void *arg, va_list ap)
 178 {
 179 #define PCHAR(c) {int cc=(c); if (func) (*func)(cc, arg); else *d++ = cc; retval++; }
 180         char nbuf[MAXNBUF];
 181         char *d;
 182         const char *p, *percent;
 183         int ch, n;
 184         uintmax_t num;
 185         int base, lflag, qflag, tmp, width, ladjust, sharpflag, neg, sign, dot;
 186         int cflag, hflag, jflag, tflag, zflag;
 187         int dwidth, upper;
 188         char padc;
 189         int stop = 0, retval = 0;
 190
 191         num = 0;
 192         if (!func)
 193                 d = (char *) arg;
 194         else
 195                 d = NULL;
 196
 197         if (fmt == NULL)
 198                 fmt = "(fmt null)\n";
 199
 200         for (;;) {
 201                 padc = ' ';
 202                 width = 0;
 203                 while ((ch = (u_char)*fmt++) != '%' || stop) {
 204                         if (ch == '\0')
 205                                 return (retval);
 206                         PCHAR(ch);
 207                 }
 208                 percent = fmt - 1;
 209                 qflag = 0; lflag = 0; ladjust = 0; sharpflag = 0; neg = 0;
 210                 sign = 0; dot = 0; dwidth = 0; upper = 0;
 211                 cflag = 0; hflag = 0; jflag = 0; tflag = 0; zflag = 0;
 212
 213 reswitch:       switch (ch = (u_char)*fmt++) {
 214                 case '.':
 215                         dot = 1;
 216                         goto reswitch;
 217                 case '#':
 218                         sharpflag = 1;
 219                         goto reswitch;
 220                 case '+':
 221                         sign = 1;
 222                         goto reswitch;
 223                 case '-':
 224                         ladjust = 1;
 225                         goto reswitch;
 226                 case '%':
 227                         PCHAR(ch);
 228                         break;
 229                 case '*':
 230                         if (!dot) {
 231                                 width = va_arg(ap, int);
 232                                 if (width < 0) {
 233                                         ladjust = !ladjust;
 234                                         width = -width;
 235                                 }
 236                         } else {
 237                                 dwidth = va_arg(ap, int);
 238                         }
 239                         goto reswitch;
 240                 case '0':
 241                         if (!dot) {
 242                                 padc = '0';
 243                                 goto reswitch;
 244                         }
 245                 case '1': case '2': case '3': case '4':
 246                 case '5': case '6': case '7': case '8': case '9':
 247                                 for (n = 0;; ++fmt) {
 248                                         n = n * 10 + ch - '0';
 249                                         ch = *fmt;
 250                                         if (ch < '0' || ch > '9')
 251                                                 break;
 252                                 }
 253                         if (dot)
 254                                 dwidth = n;
 255                         else
 256                                 width = n;
 257                         goto reswitch;
 258                 case 'c':
 259                         PCHAR(va_arg(ap, int));
 260                         break;
 261                 case 'd':
 262                 case 'i':
 263                         base = 10;
 264                         sign = 1;
 265                         goto handle_sign;
 266                 case 'h':
 267                         if (hflag) {
 268                                 hflag = 0;
 269                                 cflag = 1;
 270                         } else
 271                                 hflag = 1;
 272                         goto reswitch;
 273                 case 'j':
 274                         jflag = 1;
 275                         goto reswitch;
 276                 case 'l':
 277                         if (lflag) {
 278                                 lflag = 0;
 279                                 qflag = 1;
 280                         } else
 281                                 lflag = 1;
 282                         goto reswitch;
 283                 case 'n':
 284                         if (jflag)
 285                                 *(va_arg(ap, intmax_t *)) = retval;
 286                         else if (qflag)
 287                                 *(va_arg(ap, quad_t *)) = retval;
 288                         else if (lflag)
 289                                 *(va_arg(ap, long *)) = retval;
 290                         else if (zflag)
 291                                 *(va_arg(ap, size_t *)) = retval;
 292                         else if (hflag)
 293                                 *(va_arg(ap, short *)) = retval;
 294                         else if (cflag)
 295                                 *(va_arg(ap, char *)) = retval;
 296                         else
 297                                 *(va_arg(ap, int *)) = retval;
 298                         break;
 299                 case 'o':
 300                         base = 8;
 301                         goto handle_nosign;
 302                 case 'p':
 303                         base = 16;
 304                         sharpflag = (width == 0);
 305                         sign = 0;
 306                         num = (uintptr_t)va_arg(ap, void *);
 307                         goto number;
 308                 case 'q':
 309                         qflag = 1;
 310                         goto reswitch;
 311                 case 's':
 312                         p = va_arg(ap, char *);
 313                         if (p == NULL)
 314                                 p = "(null)";
 315                         if (!dot)
 316                                 n = strlen (p);
 317                         else
 318                                 for (n = 0; n < dwidth && p[n]; n++)
 319                                         continue;
 320
 321                         width -= n;
 322
 323                         if (!ladjust && width > 0)
 324                                 while (width--)
 325                                         PCHAR(padc);
 326                         while (n--)
 327                                 PCHAR(*p++);
 328                         if (ladjust && width > 0)
 329                                 while (width--)
 330                                         PCHAR(padc);
 331                         break;
 332                 case 't':
 333                         tflag = 1;
 334                         goto reswitch;
 335                 case 'u':
 336                         base = 10;
 337                         goto handle_nosign;
 338                 case 'X':
 339                         upper = 1;
 340                 case 'x':
 341                         base = 16;
 342                         goto handle_nosign;
 343                 case 'z':
 344                         zflag = 1;
 345                         goto reswitch;
 346 handle_nosign:
 347                         sign = 0;
 348                         if (jflag)
 349                                 num = va_arg(ap, uintmax_t);
 350                         else if (qflag)
 351                                 num = va_arg(ap, u_quad_t);
 352                         else if (tflag)
 353                                 num = va_arg(ap, ptrdiff_t);
 354                         else if (lflag)
 355                                 num = va_arg(ap, u_long);
 356                         else if (zflag)
 357                                 num = va_arg(ap, size_t);
 358                         else if (hflag)
 359                                 num = (u_short)va_arg(ap, int);
 360                         else if (cflag)
 361                                 num = (u_char)va_arg(ap, int);
 362                         else
 363                                 num = va_arg(ap, u_int);
 364                         goto number;
 365 handle_sign:
 366                         if (jflag)
 367                                 num = va_arg(ap, intmax_t);
 368                         else if (qflag)
 369                                 num = va_arg(ap, quad_t);
 370                         else if (tflag)
 371                                 num = va_arg(ap, ptrdiff_t);
 372                         else if (lflag)
 373                                 num = va_arg(ap, long);
 374                         else if (zflag)
 375                                 num = va_arg(ap, ssize_t);
 376                         else if (hflag)
 377                                 num = (short)va_arg(ap, int);
 378                         else if (cflag)
 379                                 num = (char)va_arg(ap, int);
 380                         else
 381                                 num = va_arg(ap, int);
 382 number:
 383                         if (sign && (intmax_t)num < 0) {
 384                                 neg = 1;
 385                                 num = -(intmax_t)num;
 386                         }
 387                         p = ksprintn(nbuf, num, base, &n, upper);
 388                         tmp = 0;
 389                         if (sharpflag && num != 0) {
 390                                 if (base == 8)
 391                                         tmp++;
 392                                 else if (base == 16)
 393                                         tmp += 2;
 394                         }
 395                         if (neg)
 396                                 tmp++;
 397
 398                         if (!ladjust && padc == '0')
 399                                 dwidth = width - tmp;
 400                         width -= tmp + imax(dwidth, n);
 401                         dwidth -= n;
 402                         if (!ladjust)
 403                                 while (width-- > 0)
 404                                         PCHAR(' ');
 405                         if (neg)
 406                                 PCHAR('-');
 407                         if (sharpflag && num != 0) {
 408                                 if (base == 8) {
 409                                         PCHAR('0');
 410                                 } else if (base == 16) {
 411                                         PCHAR('0');
 412                                         PCHAR('x');
 413                                 }
 414                         }
 415                         while (dwidth-- > 0)
 416                                 PCHAR('0');
 417
 418                         while (*p)
 419                                 PCHAR(*p--);
 420
 421                         if (ladjust)
 422                                 while (width-- > 0)
 423                                         PCHAR(' ');
 424
 425                         break;
 426                 default:
 427                         while (percent < fmt)
 428                                 PCHAR(*percent++);
 429                         /*
 430                          * Since we ignore an formatting argument it is no
 431                          * longer safe to obey the remaining formatting
 432                          * arguments as the arguments will no longer match
 433                          * the format specs.
 434                          */
 435                         stop = 1;
 436                         break;
 437                 }
 438         }
 439 #undef PCHAR
 440 }