/* $OpenBSD: vfscanf.c,v 1.21 2006/01/13 21:33:28 millert Exp $ */ /*- * Copyright (c) 1990, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Chris Torek. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #include #include #include #include #include #include "local.h" #ifdef FLOATING_POINT #include "floatio.h" #endif #define BUF 513 /* Maximum length of numeric string. */ /* * Flags used during conversion. */ #define LONG 0x00001 /* l: long or double */ #define LONGDBL 0x00002 /* L: long double; unimplemented */ #define SHORT 0x00004 /* h: short */ #define SHORTSHORT 0x00008 /* hh: 8 bit integer */ #define LLONG 0x00010 /* ll: long long (+ deprecated q: quad) */ #define POINTER 0x00020 /* p: void * (as hex) */ #define SIZEINT 0x00040 /* z: (signed) size_t */ #define MAXINT 0x00080 /* j: intmax_t */ #define PTRINT 0x00100 /* t: ptrdiff_t */ #define NOSKIP 0x00200 /* [ or c: do not skip blanks */ #define SUPPRESS 0x00400 /* *: suppress assignment */ #define UNSIGNED 0x00800 /* %[oupxX] conversions */ /* * The following are used in numeric conversions only: * SIGNOK, HAVESIGN, NDIGITS, DPTOK, and EXPOK are for floating point; * SIGNOK, HAVESIGN, NDIGITS, PFXOK, and NZDIGITS are for integral. */ #define SIGNOK 0x01000 /* +/- is (still) legal */ #define HAVESIGN 0x02000 /* sign detected */ #define NDIGITS 0x04000 /* no digits detected */ #define DPTOK 0x08000 /* (float) decimal point is still legal */ #define EXPOK 0x10000 /* (float) exponent (e+3, etc) still legal */ #define PFXOK 0x08000 /* 0x prefix is (still) legal */ #define NZDIGITS 0x10000 /* no zero digits detected */ /* * Conversion types. */ #define CT_CHAR 0 /* %c conversion */ #define CT_CCL 1 /* %[...] conversion */ #define CT_STRING 2 /* %s conversion */ #define CT_INT 3 /* integer, i.e., strtoimax or strtoumax */ #define CT_FLOAT 4 /* floating, i.e., strtod */ #define u_char unsigned char #define u_long unsigned long static u_char *__sccl(char *, u_char *); #if !defined(VFSCANF) #define VFSCANF vfscanf #endif /* * vfscanf */ int VFSCANF(FILE *fp, const char *fmt0, __va_list ap) { u_char *fmt = (u_char *)fmt0; int c; /* character from format, or conversion */ size_t width; /* field width, or 0 */ char *p; /* points into all kinds of strings */ int n; /* handy integer */ int flags; /* flags as defined above */ char *p0; /* saves original value of p when necessary */ int nassigned; /* number of fields assigned */ int nread; /* number of characters consumed from fp */ int base; /* base argument to strtoimax/strtouimax */ char ccltab[256]; /* character class table for %[...] */ char buf[BUF]; /* buffer for numeric conversions */ /* `basefix' is used to avoid `if' tests in the integer scanner */ static short basefix[17] = { 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 }; _SET_ORIENTATION(fp, -1); nassigned = 0; nread = 0; base = 0; /* XXX just to keep gcc happy */ for (;;) { c = *fmt++; if (c == 0) return (nassigned); if (isspace(c)) { while ((fp->_r > 0 || __srefill(fp) == 0) && isspace(*fp->_p)) nread++, fp->_r--, fp->_p++; continue; } if (c != '%') goto literal; width = 0; flags = 0; /* * switch on the format. continue if done; * break once format type is derived. */ again: c = *fmt++; switch (c) { case '%': literal: if (fp->_r <= 0 && __srefill(fp)) goto input_failure; if (*fp->_p != c) goto match_failure; fp->_r--, fp->_p++; nread++; continue; case '*': flags |= SUPPRESS; goto again; case 'j': flags |= MAXINT; goto again; case 'L': flags |= LONGDBL; goto again; case 'h': if (*fmt == 'h') { fmt++; flags |= SHORTSHORT; } else { flags |= SHORT; } goto again; case 'l': if (*fmt == 'l') { fmt++; flags |= LLONG; } else { flags |= LONG; } goto again; case 'q': flags |= LLONG; /* deprecated */ goto again; case 't': flags |= PTRINT; goto again; case 'z': flags |= SIZEINT; goto again; case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': width = width * 10 + c - '0'; goto again; /* * Conversions. * Those marked `compat' are for 4.[123]BSD compatibility. * * (According to ANSI, E and X formats are supposed * to the same as e and x. Sorry about that.) */ case 'D': /* compat */ flags |= LONG; /* FALLTHROUGH */ case 'd': c = CT_INT; base = 10; break; case 'i': c = CT_INT; base = 0; break; case 'O': /* compat */ flags |= LONG; /* FALLTHROUGH */ case 'o': c = CT_INT; flags |= UNSIGNED; base = 8; break; case 'u': c = CT_INT; flags |= UNSIGNED; base = 10; break; case 'X': case 'x': flags |= PFXOK; /* enable 0x prefixing */ c = CT_INT; flags |= UNSIGNED; base = 16; break; #ifdef FLOATING_POINT case 'E': case 'G': case 'e': case 'f': case 'g': c = CT_FLOAT; break; #endif case 's': c = CT_STRING; break; case '[': fmt = __sccl(ccltab, fmt); flags |= NOSKIP; c = CT_CCL; break; case 'c': flags |= NOSKIP; c = CT_CHAR; break; case 'p': /* pointer format is like hex */ flags |= POINTER | PFXOK; c = CT_INT; flags |= UNSIGNED; base = 16; break; case 'n': if (flags & SUPPRESS) continue; if (flags & SHORTSHORT) *va_arg(ap, __signed char *) = nread; else if (flags & SHORT) *va_arg(ap, short *) = nread; else if (flags & LONG) *va_arg(ap, long *) = nread; else if (flags & SIZEINT) *va_arg(ap, ssize_t *) = nread; else if (flags & PTRINT) *va_arg(ap, ptrdiff_t *) = nread; else if (flags & LLONG) *va_arg(ap, long long *) = nread; else if (flags & MAXINT) *va_arg(ap, intmax_t *) = nread; else *va_arg(ap, int *) = nread; continue; /* * Disgusting backwards compatibility hacks. XXX */ case '\0': /* compat */ return (EOF); default: /* compat */ if (isupper(c)) flags |= LONG; c = CT_INT; base = 10; break; } /* * We have a conversion that requires input. */ if (fp->_r <= 0 && __srefill(fp)) goto input_failure; /* * Consume leading white space, except for formats * that suppress this. */ if ((flags & NOSKIP) == 0) { while (isspace(*fp->_p)) { nread++; if (--fp->_r > 0) fp->_p++; else if (__srefill(fp)) goto input_failure; } /* * Note that there is at least one character in * the buffer, so conversions that do not set NOSKIP * ca no longer result in an input failure. */ } /* * Do the conversion. */ switch (c) { case CT_CHAR: /* scan arbitrary characters (sets NOSKIP) */ if (width == 0) width = 1; if (flags & SUPPRESS) { size_t sum = 0; for (;;) { if ((n = fp->_r) < width) { sum += n; width -= n; fp->_p += n; if (__srefill(fp)) { if (sum == 0) goto input_failure; break; } } else { sum += width; fp->_r -= width; fp->_p += width; break; } } nread += sum; } else { size_t r = fread((void *)va_arg(ap, char *), 1, width, fp); if (r == 0) goto input_failure; nread += r; nassigned++; } break; case CT_CCL: /* scan a (nonempty) character class (sets NOSKIP) */ if (width == 0) width = (size_t)~0; /* `infinity' */ /* take only those things in the class */ if (flags & SUPPRESS) { n = 0; while (ccltab[*fp->_p]) { n++, fp->_r--, fp->_p++; if (--width == 0) break; if (fp->_r <= 0 && __srefill(fp)) { if (n == 0) goto input_failure; break; } } if (n == 0) goto match_failure; } else { p0 = p = va_arg(ap, char *); while (ccltab[*fp->_p]) { fp->_r--; *p++ = *fp->_p++; if (--width == 0) break; if (fp->_r <= 0 && __srefill(fp)) { if (p == p0) goto input_failure; break; } } n = p - p0; if (n == 0) goto match_failure; *p = '\0'; nassigned++; } nread += n; break; case CT_STRING: /* like CCL, but zero-length string OK, & no NOSKIP */ if (width == 0) width = (size_t)~0; if (flags & SUPPRESS) { n = 0; while (!isspace(*fp->_p)) { n++, fp->_r--, fp->_p++; if (--width == 0) break; if (fp->_r <= 0 && __srefill(fp)) break; } nread += n; } else { p0 = p = va_arg(ap, char *); while (!isspace(*fp->_p)) { fp->_r--; *p++ = *fp->_p++; if (--width == 0) break; if (fp->_r <= 0 && __srefill(fp)) break; } *p = '\0'; nread += p - p0; nassigned++; } continue; case CT_INT: /* scan an integer as if by strtoimax/strtoumax */ #ifdef hardway if (width == 0 || width > sizeof(buf) - 1) width = sizeof(buf) - 1; #else /* size_t is unsigned, hence this optimisation */ if (--width > sizeof(buf) - 2) width = sizeof(buf) - 2; width++; #endif flags |= SIGNOK | NDIGITS | NZDIGITS; for (p = buf; width; width--) { c = *fp->_p; /* * Switch on the character; `goto ok' * if we accept it as a part of number. */ switch (c) { /* * The digit 0 is always legal, but is * special. For %i conversions, if no * digits (zero or nonzero) have been * scanned (only signs), we will have * base==0. In that case, we should set * it to 8 and enable 0x prefixing. * Also, if we have not scanned zero digits * before this, do not turn off prefixing * (someone else will turn it off if we * have scanned any nonzero digits). */ case '0': if (base == 0) { base = 8; flags |= PFXOK; } if (flags & NZDIGITS) flags &= ~(SIGNOK|NZDIGITS|NDIGITS); else flags &= ~(SIGNOK|PFXOK|NDIGITS); goto ok; /* 1 through 7 always legal */ case '1': case '2': case '3': case '4': case '5': case '6': case '7': base = basefix[base]; flags &= ~(SIGNOK | PFXOK | NDIGITS); goto ok; /* digits 8 and 9 ok iff decimal or hex */ case '8': case '9': base = basefix[base]; if (base <= 8) break; /* not legal here */ flags &= ~(SIGNOK | PFXOK | NDIGITS); goto ok; /* letters ok iff hex */ case 'A': case 'B': case 'C': case 'D': case 'E': case 'F': case 'a': case 'b': case 'c': case 'd': case 'e': case 'f': /* no need to fix base here */ if (base <= 10) break; /* not legal here */ flags &= ~(SIGNOK | PFXOK | NDIGITS); goto ok; /* sign ok only as first character */ case '+': case '-': if (flags & SIGNOK) { flags &= ~SIGNOK; flags |= HAVESIGN; goto ok; } break; /* * x ok iff flag still set and 2nd char (or * 3rd char if we have a sign). */ case 'x': case 'X': if ((flags & PFXOK) && p == buf + 1 + !!(flags & HAVESIGN)) { base = 16; /* if %i */ flags &= ~PFXOK; goto ok; } break; } /* * If we got here, c is not a legal character * for a number. Stop accumulating digits. */ break; ok: /* * c is legal: store it and look at the next. */ *p++ = c; if (--fp->_r > 0) fp->_p++; else if (__srefill(fp)) break; /* EOF */ } /* * If we had only a sign, it is no good; push * back the sign. If the number ends in `x', * it was [sign] '0' 'x', so push back the x * and treat it as [sign] '0'. */ if (flags & NDIGITS) { if (p > buf) (void) ungetc(*(u_char *)--p, fp); goto match_failure; } c = ((u_char *)p)[-1]; if (c == 'x' || c == 'X') { --p; (void) ungetc(c, fp); } if ((flags & SUPPRESS) == 0) { uintmax_t res; *p = '\0'; if (flags & UNSIGNED) res = strtoumax(buf, NULL, base); else res = strtoimax(buf, NULL, base); if (flags & POINTER) *va_arg(ap, void **) = (void *)(uintptr_t)res; else if (flags & MAXINT) *va_arg(ap, intmax_t *) = res; else if (flags & LLONG) *va_arg(ap, long long *) = res; else if (flags & SIZEINT) *va_arg(ap, ssize_t *) = res; else if (flags & PTRINT) *va_arg(ap, ptrdiff_t *) = res; else if (flags & LONG) *va_arg(ap, long *) = res; else if (flags & SHORT) *va_arg(ap, short *) = res; else if (flags & SHORTSHORT) *va_arg(ap, __signed char *) = res; else *va_arg(ap, int *) = res; nassigned++; } nread += p - buf; break; #ifdef FLOATING_POINT case CT_FLOAT: /* scan a floating point number as if by strtod */ #ifdef hardway if (width == 0 || width > sizeof(buf) - 1) width = sizeof(buf) - 1; #else /* size_t is unsigned, hence this optimisation */ if (--width > sizeof(buf) - 2) width = sizeof(buf) - 2; width++; #endif flags |= SIGNOK | NDIGITS | DPTOK | EXPOK; for (p = buf; width; width--) { c = *fp->_p; /* * This code mimicks the integer conversion * code, but is much simpler. */ switch (c) { case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': flags &= ~(SIGNOK | NDIGITS); goto fok; case '+': case '-': if (flags & SIGNOK) { flags &= ~SIGNOK; goto fok; } break; case '.': if (flags & DPTOK) { flags &= ~(SIGNOK | DPTOK); goto fok; } break; case 'e': case 'E': /* no exponent without some digits */ if ((flags&(NDIGITS|EXPOK)) == EXPOK) { flags = (flags & ~(EXPOK|DPTOK)) | SIGNOK | NDIGITS; goto fok; } break; } break; fok: *p++ = c; if (--fp->_r > 0) fp->_p++; else if (__srefill(fp)) break; /* EOF */ } /* * If no digits, might be missing exponent digits * (just give back the exponent) or might be missing * regular digits, but had sign and/or decimal point. */ if (flags & NDIGITS) { if (flags & EXPOK) { /* no digits at all */ while (p > buf) ungetc(*(u_char *)--p, fp); goto match_failure; } /* just a bad exponent (e and maybe sign) */ c = *(u_char *)--p; if (c != 'e' && c != 'E') { (void) ungetc(c, fp);/* sign */ c = *(u_char *)--p; } (void) ungetc(c, fp); } if ((flags & SUPPRESS) == 0) { double res; *p = '\0'; res = strtod(buf, (char **) NULL); if (flags & LONGDBL) *va_arg(ap, long double *) = res; else if (flags & LONG) *va_arg(ap, double *) = res; else *va_arg(ap, float *) = res; nassigned++; } nread += p - buf; break; #endif /* FLOATING_POINT */ } } input_failure: return (nassigned ? nassigned : -1); match_failure: return (nassigned); } /* * Fill in the given table from the scanset at the given format * (just after `['). Return a pointer to the character past the * closing `]'. The table has a 1 wherever characters should be * considered part of the scanset. */ static u_char * __sccl(char *tab, u_char *fmt) { int c, n, v; /* first `clear' the whole table */ c = *fmt++; /* first char hat => negated scanset */ if (c == '^') { v = 1; /* default => accept */ c = *fmt++; /* get new first char */ } else v = 0; /* default => reject */ /* should probably use memset here */ for (n = 0; n < 256; n++) tab[n] = v; if (c == 0) return (fmt - 1);/* format ended before closing ] */ /* * Now set the entries corresponding to the actual scanset * to the opposite of the above. * * The first character may be ']' (or '-') without being special; * the last character may be '-'. */ v = 1 - v; for (;;) { tab[c] = v; /* take character c */ doswitch: n = *fmt++; /* and examine the next */ switch (n) { case 0: /* format ended too soon */ return (fmt - 1); case '-': /* * A scanset of the form * [01+-] * is defined as `the digit 0, the digit 1, * the character +, the character -', but * the effect of a scanset such as * [a-zA-Z0-9] * is implementation defined. The V7 Unix * scanf treats `a-z' as `the letters a through * z', but treats `a-a' as `the letter a, the * character -, and the letter a'. * * For compatibility, the `-' is not considerd * to define a range if the character following * it is either a close bracket (required by ANSI) * or is not numerically greater than the character * we just stored in the table (c). */ n = *fmt; if (n == ']' || n < c) { c = '-'; break; /* resume the for(;;) */ } fmt++; do { /* fill in the range */ tab[++c] = v; } while (c < n); #if 1 /* XXX another disgusting compatibility hack */ /* * Alas, the V7 Unix scanf also treats formats * such as [a-c-e] as `the letters a through e'. * This too is permitted by the standard.... */ goto doswitch; #else c = *fmt++; if (c == 0) return (fmt - 1); if (c == ']') return (fmt); #endif break; case ']': /* end of scanset */ return (fmt); default: /* just another character */ c = n; break; } } /* NOTREACHED */ }