![[BACK]](/icons/back.gif){kind=icon}
Return to vfscanf.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / prex-old / usr / lib / libc / stdio|
Return to vfscanf.c CVS log | Up to [local] / prex-old / usr / lib / libc / stdio |
1.1 ! nbrk 1: /*-
! 2: * Copyright (c) 1990, 1993
! 3: * The Regents of the University of California. All rights reserved.
! 4: *
! 5: * This code is derived from software contributed to Berkeley by
! 6: * Chris Torek.
! 7: *
! 8: * Redistribution and use in source and binary forms, with or without
! 9: * modification, are permitted provided that the following conditions
! 10: * are met:
! 11: * 1. Redistributions of source code must retain the above copyright
! 12: * notice, this list of conditions and the following disclaimer.
! 13: * 2. Redistributions in binary form must reproduce the above copyright
! 14: * notice, this list of conditions and the following disclaimer in the
! 15: * documentation and/or other materials provided with the distribution.
! 16: * 3. Neither the name of the University nor the names of its contributors
! 17: * may be used to endorse or promote products derived from this software
! 18: * without specific prior written permission.
! 19: *
! 20: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
! 21: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
! 22: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
! 23: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
! 24: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
! 25: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
! 26: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
! 27: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
! 28: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
! 29: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
! 30: * SUCH DAMAGE.
! 31: */
! 32:
! 33: #include <stdio.h>
! 34: #include <stdlib.h>
! 35: #include <ctype.h>
! 36: #include <stdarg.h>
! 37: #include "local.h"
! 38:
! 39: #define BUF 513 /* Maximum length of numeric string. */
! 40:
! 41: /*
! 42: * Flags used during conversion.
! 43: */
! 44: #define LONG 0x01 /* l: long or double */
! 45: #define LONGDBL 0x02 /* L: long double; unimplemented */
! 46: #define SHORT 0x04 /* h: short */
! 47: #define SUPPRESS 0x08 /* suppress assignment */
! 48: #define POINTER 0x10 /* weird %p pointer (`fake hex') */
! 49: #define NOSKIP 0x20 /* do not skip blanks */
! 50:
! 51: /*
! 52: * The following are used in numeric conversions only:
! 53: * SIGNOK, NDIGITS, DPTOK, and EXPOK are for floating point;
! 54: * SIGNOK, NDIGITS, PFXOK, and NZDIGITS are for integral.
! 55: */
! 56: #define SIGNOK 0x40 /* +/- is (still) legal */
! 57: #define NDIGITS 0x80 /* no digits detected */
! 58:
! 59: #define DPTOK 0x100 /* (float) decimal point is still legal */
! 60: #define EXPOK 0x200 /* (float) exponent (e+3, etc) still legal */
! 61:
! 62: #define PFXOK 0x100 /* 0x prefix is (still) legal */
! 63: #define NZDIGITS 0x200 /* no zero digits detected */
! 64:
! 65: /*
! 66: * Conversion types.
! 67: */
! 68: #define CT_CHAR 0 /* %c conversion */
! 69: #define CT_CCL 1 /* %[...] conversion */
! 70: #define CT_STRING 2 /* %s conversion */
! 71: #define CT_INT 3 /* integer, i.e., strtol or strtoul */
! 72: #define CT_FLOAT 4 /* floating, i.e., strtod */
! 73:
! 74: #define u_char unsigned char
! 75: #define u_long unsigned long
! 76:
! 77: static u_char *__sccl(char *, u_char *);
! 78:
! 79: /*
! 80: * vfscanf
! 81: */
! 82: int
! 83: __svfscanf(fp, fmt0, ap)
! 84: FILE *fp;
! 85: char const *fmt0;
! 86: va_list ap;
! 87: {
! 88: u_char *fmt = (u_char *)fmt0;
! 89: int c; /* character from format, or conversion */
! 90: size_t width; /* field width, or 0 */
! 91: char *p; /* points into all kinds of strings */
! 92: int n; /* handy integer */
! 93: int flags; /* flags as defined above */
! 94: char *p0; /* saves original value of p when necessary */
! 95: int nassigned; /* number of fields assigned */
! 96: int nread; /* number of characters consumed from fp */
! 97: int base; /* base argument to strtol/strtoul */
! 98: u_long (*ccfn)(const char *, char **, int);
! 99: /* conversion function (strtol/strtoul) */
! 100: char ccltab[256]; /* character class table for %[...] */
! 101: char buf[BUF]; /* buffer for numeric conversions */
! 102:
! 103: /* `basefix' is used to avoid `if' tests in the integer scanner */
! 104: static short basefix[17] =
! 105: { 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 };
! 106:
! 107: nassigned = 0;
! 108: nread = 0;
! 109: base = 0; /* XXX just to keep gcc happy */
! 110: ccfn = NULL; /* XXX just to keep gcc happy */
! 111: for (;;) {
! 112: c = *fmt++;
! 113: if (c == 0)
! 114: return (nassigned);
! 115: if (isspace(c)) {
! 116: for (;;) {
! 117: if (fp->_r <= 0 && __srefill(fp))
! 118: return (nassigned);
! 119: if (!isspace(*fp->_p))
! 120: break;
! 121: nread++, fp->_r--, fp->_p++;
! 122: }
! 123: continue;
! 124: }
! 125: if (c != '%')
! 126: goto literal;
! 127: width = 0;
! 128: flags = 0;
! 129: /*
! 130: * switch on the format. continue if done;
! 131: * break once format type is derived.
! 132: */
! 133: again: c = *fmt++;
! 134: switch (c) {
! 135: case '%':
! 136: literal:
! 137: if (fp->_r <= 0 && __srefill(fp))
! 138: goto input_failure;
! 139: if (*fp->_p != c)
! 140: goto match_failure;
! 141: fp->_r--, fp->_p++;
! 142: nread++;
! 143: continue;
! 144:
! 145: case '*':
! 146: flags |= SUPPRESS;
! 147: goto again;
! 148: case 'l':
! 149: flags |= LONG;
! 150: goto again;
! 151: case 'L':
! 152: flags |= LONGDBL;
! 153: goto again;
! 154: case 'h':
! 155: flags |= SHORT;
! 156: goto again;
! 157:
! 158: case '0': case '1': case '2': case '3': case '4':
! 159: case '5': case '6': case '7': case '8': case '9':
! 160: width = width * 10 + c - '0';
! 161: goto again;
! 162:
! 163: /*
! 164: * Conversions.
! 165: * Those marked `compat' are for 4.[123]BSD compatibility.
! 166: *
! 167: * (According to ANSI, E and X formats are supposed
! 168: * to the same as e and x. Sorry about that.)
! 169: */
! 170: case 'D': /* compat */
! 171: flags |= LONG;
! 172: /* FALLTHROUGH */
! 173: case 'd':
! 174: c = CT_INT;
! 175: ccfn = (u_long (*)(const char *, char **, int))strtol;
! 176: base = 10;
! 177: break;
! 178:
! 179: case 'i':
! 180: c = CT_INT;
! 181: ccfn = (u_long (*)(const char *, char **, int))strtol;
! 182: base = 0;
! 183: break;
! 184:
! 185: case 'O': /* compat */
! 186: flags |= LONG;
! 187: /* FALLTHROUGH */
! 188: case 'o':
! 189: c = CT_INT;
! 190: ccfn = strtoul;
! 191: base = 8;
! 192: break;
! 193:
! 194: case 'u':
! 195: c = CT_INT;
! 196: ccfn = strtoul;
! 197: base = 10;
! 198: break;
! 199:
! 200: case 'X': /* compat XXX */
! 201: flags |= LONG;
! 202: /* FALLTHROUGH */
! 203: case 'x':
! 204: flags |= PFXOK; /* enable 0x prefixing */
! 205: c = CT_INT;
! 206: ccfn = strtoul;
! 207: base = 16;
! 208: break;
! 209:
! 210: case 's':
! 211: c = CT_STRING;
! 212: break;
! 213:
! 214: case '[':
! 215: fmt = __sccl(ccltab, fmt);
! 216: flags |= NOSKIP;
! 217: c = CT_CCL;
! 218: break;
! 219:
! 220: case 'c':
! 221: flags |= NOSKIP;
! 222: c = CT_CHAR;
! 223: break;
! 224:
! 225: case 'p': /* pointer format is like hex */
! 226: flags |= POINTER | PFXOK;
! 227: c = CT_INT;
! 228: ccfn = strtoul;
! 229: base = 16;
! 230: break;
! 231:
! 232: case 'n':
! 233: if (flags & SUPPRESS) /* ??? */
! 234: continue;
! 235: if (flags & SHORT)
! 236: *va_arg(ap, short *) = nread;
! 237: else if (flags & LONG)
! 238: *va_arg(ap, long *) = nread;
! 239: else
! 240: *va_arg(ap, int *) = nread;
! 241: continue;
! 242:
! 243: /*
! 244: * Disgusting backwards compatibility hacks. XXX
! 245: */
! 246: case '\0': /* compat */
! 247: return (EOF);
! 248:
! 249: default: /* compat */
! 250: if (isupper(c))
! 251: flags |= LONG;
! 252: c = CT_INT;
! 253: ccfn = (u_long (*)(const char *, char **, int))strtol;
! 254: base = 10;
! 255: break;
! 256: }
! 257:
! 258: /*
! 259: * We have a conversion that requires input.
! 260: */
! 261: if (fp->_r <= 0 && __srefill(fp))
! 262: goto input_failure;
! 263:
! 264: /*
! 265: * Consume leading white space, except for formats
! 266: * that suppress this.
! 267: */
! 268: if ((flags & NOSKIP) == 0) {
! 269: while (isspace(*fp->_p)) {
! 270: nread++;
! 271: if (--fp->_r > 0)
! 272: fp->_p++;
! 273: else if (__srefill(fp))
! 274: goto input_failure;
! 275: }
! 276: /*
! 277: * Note that there is at least one character in
! 278: * the buffer, so conversions that do not set NOSKIP
! 279: * ca no longer result in an input failure.
! 280: */
! 281: }
! 282:
! 283: /*
! 284: * Do the conversion.
! 285: */
! 286: switch (c) {
! 287:
! 288: case CT_CHAR:
! 289: /* scan arbitrary characters (sets NOSKIP) */
! 290: if (width == 0)
! 291: width = 1;
! 292: if (flags & SUPPRESS) {
! 293: size_t sum = 0;
! 294: for (;;) {
! 295: if ((size_t)(n = fp->_r) < width) {
! 296: sum += n;
! 297: width -= n;
! 298: fp->_p += n;
! 299: if (__srefill(fp)) {
! 300: if (sum == 0)
! 301: goto input_failure;
! 302: break;
! 303: }
! 304: } else {
! 305: sum += width;
! 306: fp->_r -= width;
! 307: fp->_p += width;
! 308: break;
! 309: }
! 310: }
! 311: nread += sum;
! 312: } else {
! 313: size_t r = fread((void *)va_arg(ap, char *), 1,
! 314: width, fp);
! 315:
! 316: if (r == 0)
! 317: goto input_failure;
! 318: nread += r;
! 319: nassigned++;
! 320: }
! 321: break;
! 322:
! 323: case CT_CCL:
! 324: /* scan a (nonempty) character class (sets NOSKIP) */
! 325: if (width == 0)
! 326: width = ~0; /* `infinity' */
! 327: /* take only those things in the class */
! 328: if (flags & SUPPRESS) {
! 329: n = 0;
! 330: while (ccltab[*fp->_p]) {
! 331: n++, fp->_r--, fp->_p++;
! 332: if (--width == 0)
! 333: break;
! 334: if (fp->_r <= 0 && __srefill(fp)) {
! 335: if (n == 0)
! 336: goto input_failure;
! 337: break;
! 338: }
! 339: }
! 340: if (n == 0)
! 341: goto match_failure;
! 342: } else {
! 343: p0 = p = va_arg(ap, char *);
! 344: while (ccltab[*fp->_p]) {
! 345: fp->_r--;
! 346: *p++ = *fp->_p++;
! 347: if (--width == 0)
! 348: break;
! 349: if (fp->_r <= 0 && __srefill(fp)) {
! 350: if (p == p0)
! 351: goto input_failure;
! 352: break;
! 353: }
! 354: }
! 355: n = p - p0;
! 356: if (n == 0)
! 357: goto match_failure;
! 358: *p = 0;
! 359: nassigned++;
! 360: }
! 361: nread += n;
! 362: break;
! 363:
! 364: case CT_STRING:
! 365: /* like CCL, but zero-length string OK, & no NOSKIP */
! 366: if (width == 0)
! 367: width = ~0;
! 368: if (flags & SUPPRESS) {
! 369: n = 0;
! 370: while (!isspace(*fp->_p)) {
! 371: n++, fp->_r--, fp->_p++;
! 372: if (--width == 0)
! 373: break;
! 374: if (fp->_r <= 0 && __srefill(fp))
! 375: break;
! 376: }
! 377: nread += n;
! 378: } else {
! 379: p0 = p = va_arg(ap, char *);
! 380: while (!isspace(*fp->_p)) {
! 381: fp->_r--;
! 382: *p++ = *fp->_p++;
! 383: if (--width == 0)
! 384: break;
! 385: if (fp->_r <= 0 && __srefill(fp))
! 386: break;
! 387: }
! 388: *p = 0;
! 389: nread += p - p0;
! 390: nassigned++;
! 391: }
! 392: continue;
! 393:
! 394: case CT_INT:
! 395: /* scan an integer as if by strtol/strtoul */
! 396: #ifdef hardway
! 397: if (width == 0 || width > sizeof(buf) - 1)
! 398: width = sizeof(buf) - 1;
! 399: #else
! 400: /* size_t is unsigned, hence this optimisation */
! 401: if (--width > sizeof(buf) - 2)
! 402: width = sizeof(buf) - 2;
! 403: width++;
! 404: #endif
! 405: flags |= SIGNOK | NDIGITS | NZDIGITS;
! 406: for (p = buf; width; width--) {
! 407: c = *fp->_p;
! 408: /*
! 409: * Switch on the character; `goto ok'
! 410: * if we accept it as a part of number.
! 411: */
! 412: switch (c) {
! 413:
! 414: /*
! 415: * The digit 0 is always legal, but is
! 416: * special. For %i conversions, if no
! 417: * digits (zero or nonzero) have been
! 418: * scanned (only signs), we will have
! 419: * base==0. In that case, we should set
! 420: * it to 8 and enable 0x prefixing.
! 421: * Also, if we have not scanned zero digits
! 422: * before this, do not turn off prefixing
! 423: * (someone else will turn it off if we
! 424: * have scanned any nonzero digits).
! 425: */
! 426: case '0':
! 427: if (base == 0) {
! 428: base = 8;
! 429: flags |= PFXOK;
! 430: }
! 431: if (flags & NZDIGITS)
! 432: flags &= ~(SIGNOK|NZDIGITS|NDIGITS);
! 433: else
! 434: flags &= ~(SIGNOK|PFXOK|NDIGITS);
! 435: goto ok;
! 436:
! 437: /* 1 through 7 always legal */
! 438: case '1': case '2': case '3':
! 439: case '4': case '5': case '6': case '7':
! 440: base = basefix[base];
! 441: flags &= ~(SIGNOK | PFXOK | NDIGITS);
! 442: goto ok;
! 443:
! 444: /* digits 8 and 9 ok iff decimal or hex */
! 445: case '8': case '9':
! 446: base = basefix[base];
! 447: if (base <= 8)
! 448: break; /* not legal here */
! 449: flags &= ~(SIGNOK | PFXOK | NDIGITS);
! 450: goto ok;
! 451:
! 452: /* letters ok iff hex */
! 453: case 'A': case 'B': case 'C':
! 454: case 'D': case 'E': case 'F':
! 455: case 'a': case 'b': case 'c':
! 456: case 'd': case 'e': case 'f':
! 457: /* no need to fix base here */
! 458: if (base <= 10)
! 459: break; /* not legal here */
! 460: flags &= ~(SIGNOK | PFXOK | NDIGITS);
! 461: goto ok;
! 462:
! 463: /* sign ok only as first character */
! 464: case '+': case '-':
! 465: if (flags & SIGNOK) {
! 466: flags &= ~SIGNOK;
! 467: goto ok;
! 468: }
! 469: break;
! 470:
! 471: /* x ok iff flag still set & 2nd char */
! 472: case 'x': case 'X':
! 473: if (flags & PFXOK && p == buf + 1) {
! 474: base = 16; /* if %i */
! 475: flags &= ~PFXOK;
! 476: goto ok;
! 477: }
! 478: break;
! 479: }
! 480:
! 481: /*
! 482: * If we got here, c is not a legal character
! 483: * for a number. Stop accumulating digits.
! 484: */
! 485: break;
! 486: ok:
! 487: /*
! 488: * c is legal: store it and look at the next.
! 489: */
! 490: *p++ = c;
! 491: if (--fp->_r > 0)
! 492: fp->_p++;
! 493: else if (__srefill(fp))
! 494: break; /* EOF */
! 495: }
! 496: /*
! 497: * If we had only a sign, it is no good; push
! 498: * back the sign. If the number ends in `x',
! 499: * it was [sign] '0' 'x', so push back the x
! 500: * and treat it as [sign] '0'.
! 501: */
! 502: if (flags & NDIGITS) {
! 503: if (p > buf)
! 504: (void) ungetc(*(u_char *)--p, fp);
! 505: goto match_failure;
! 506: }
! 507: c = ((u_char *)p)[-1];
! 508: if (c == 'x' || c == 'X') {
! 509: --p;
! 510: (void) ungetc(c, fp);
! 511: }
! 512: if ((flags & SUPPRESS) == 0) {
! 513: u_long res;
! 514:
! 515: *p = 0;
! 516: res = (*ccfn)(buf, (char **)NULL, base);
! 517: if (flags & POINTER)
! 518: *va_arg(ap, void **) = (void *)res;
! 519: else if (flags & SHORT)
! 520: *va_arg(ap, short *) = res;
! 521: else if (flags & LONG)
! 522: *va_arg(ap, long *) = res;
! 523: else
! 524: *va_arg(ap, int *) = res;
! 525: nassigned++;
! 526: }
! 527: nread += p - buf;
! 528: break;
! 529:
! 530: }
! 531: }
! 532: input_failure:
! 533: return (nassigned ? nassigned : -1);
! 534: match_failure:
! 535: return (nassigned);
! 536: }
! 537:
! 538: /*
! 539: * Fill in the given table from the scanset at the given format
! 540: * (just after `['). Return a pointer to the character past the
! 541: * closing `]'. The table has a 1 wherever characters should be
! 542: * considered part of the scanset.
! 543: */
! 544: static u_char *
! 545: __sccl(tab, fmt)
! 546: char *tab;
! 547: u_char *fmt;
! 548: {
! 549: int c, n, v;
! 550:
! 551: /* first `clear' the whole table */
! 552: c = *fmt++; /* first char hat => negated scanset */
! 553: if (c == '^') {
! 554: v = 1; /* default => accept */
! 555: c = *fmt++; /* get new first char */
! 556: } else
! 557: v = 0; /* default => reject */
! 558: /* should probably use memset here */
! 559: for (n = 0; n < 256; n++)
! 560: tab[n] = v;
! 561: if (c == 0)
! 562: return (fmt - 1);/* format ended before closing ] */
! 563:
! 564: /*
! 565: * Now set the entries corresponding to the actual scanset
! 566: * to the opposite of the above.
! 567: *
! 568: * The first character may be ']' (or '-') without being special;
! 569: * the last character may be '-'.
! 570: */
! 571: v = 1 - v;
! 572: for (;;) {
! 573: tab[c] = v; /* take character c */
! 574: doswitch:
! 575: n = *fmt++; /* and examine the next */
! 576: switch (n) {
! 577:
! 578: case 0: /* format ended too soon */
! 579: return (fmt - 1);
! 580:
! 581: case '-':
! 582: /*
! 583: * A scanset of the form
! 584: * [01+-]
! 585: * is defined as `the digit 0, the digit 1,
! 586: * the character +, the character -', but
! 587: * the effect of a scanset such as
! 588: * [a-zA-Z0-9]
! 589: * is implementation defined. The V7 Unix
! 590: * scanf treats `a-z' as `the letters a through
! 591: * z', but treats `a-a' as `the letter a, the
! 592: * character -, and the letter a'.
! 593: *
! 594: * For compatibility, the `-' is not considerd
! 595: * to define a range if the character following
! 596: * it is either a close bracket (required by ANSI)
! 597: * or is not numerically greater than the character
! 598: * we just stored in the table (c).
! 599: */
! 600: n = *fmt;
! 601: if (n == ']' || n < c) {
! 602: c = '-';
! 603: break; /* resume the for(;;) */
! 604: }
! 605: fmt++;
! 606: do { /* fill in the range */
! 607: tab[++c] = v;
! 608: } while (c < n);
! 609: #if 1 /* XXX another disgusting compatibility hack */
! 610: /*
! 611: * Alas, the V7 Unix scanf also treats formats
! 612: * such as [a-c-e] as `the letters a through e'.
! 613: * This too is permitted by the standard....
! 614: */
! 615: goto doswitch;
! 616: #else
! 617: c = *fmt++;
! 618: if (c == 0)
! 619: return (fmt - 1);
! 620: if (c == ']')
! 621: return (fmt);
! 622: #endif
! 623: break;
! 624:
! 625: case ']': /* end of scanset */
! 626: return (fmt);
! 627:
! 628: default: /* just another character */
! 629: c = n;
! 630: break;
! 631: }
! 632: }
! 633: /* NOTREACHED */
! 634: }