| /* $OpenBSD: vfscanf.c,v 1.31 2014/03/19 05:17:01 guenther 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 "scanf_common.h" |
| |
| static const unsigned char* __sccl(char*, const unsigned char*); |
| |
| /* |
| * Internal, unlocked version of vfscanf |
| */ |
| int __svfscanf(FILE* fp, const char* fmt0, va_list ap) { |
| const unsigned char* fmt = reinterpret_cast<const unsigned char*>(fmt0); |
| int c; /* character from format, or conversion */ |
| size_t width; /* field width, or 0 */ |
| char* p; |
| wchar_t* wcp; |
| size_t n; |
| int flags; /* flags as defined above */ |
| 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 */ |
| size_t nconv; /* length of multibyte sequence converted */ |
| mbstate_t mbs; |
| void* allocation = nullptr; // Allocated but unassigned result for %mc/%ms/%m[. |
| size_t capacity = 0; // Number of char/wchar_t units allocated in `allocation`. |
| |
| _SET_ORIENTATION(fp, ORIENT_BYTES); |
| |
| nassigned = 0; |
| nread = 0; |
| 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++; |
| reswitch: |
| 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 'm': |
| flags |= ALLOCATE; |
| 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. |
| */ |
| case 'b': |
| c = CT_INT; |
| base = 2; |
| flags |= PFBOK; /* enable 0b prefixing */ |
| break; |
| |
| case 'D': /* compat */ |
| flags |= LONG; |
| __BIONIC_FALLTHROUGH; |
| case 'd': |
| c = CT_INT; |
| base = 10; |
| break; |
| |
| case 'i': |
| c = CT_INT; |
| base = 0; |
| break; |
| |
| case 'O': /* compat */ |
| flags |= LONG; |
| __BIONIC_FALLTHROUGH; |
| case 'o': |
| c = CT_INT; |
| flags |= UNSIGNED; |
| base = 8; |
| break; |
| |
| case 'u': |
| c = CT_INT; |
| flags |= UNSIGNED; |
| base = 10; |
| break; |
| |
| case 'w': { |
| int size = 0; |
| bool fast = false; |
| c = *fmt++; |
| if (c == 'f') { |
| fast = true; |
| c = *fmt++; |
| } |
| while (is_digit(c)) { |
| APPEND_DIGIT(size, c); |
| c = *fmt++; |
| } |
| flags |= w_to_flag(size, fast); |
| goto reswitch; |
| } |
| |
| case 'X': |
| case 'x': |
| flags |= PFXOK; /* enable 0x prefixing */ |
| c = CT_INT; |
| flags |= UNSIGNED; |
| base = 16; |
| break; |
| |
| case 'e': |
| case 'E': |
| case 'f': |
| case 'F': |
| case 'g': |
| case 'G': |
| case 'a': |
| case 'A': |
| c = CT_FLOAT; |
| break; |
| |
| case 's': |
| memset(ccltab, 1, 256); |
| ccltab['\t'] = ccltab['\n'] = ccltab['\v'] = ccltab['\f'] = ccltab['\r'] = ccltab[' '] = 0; |
| 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; |
| } |
| |
| if ((flags & ALLOCATE) != 0 && c > CT_STRING) { |
| __fortify_fatal("scanf 'm' only works with %%c/%%s/%%["); |
| } |
| if ((flags & (ALLOCATE|SUPPRESS)) == (ALLOCATE|SUPPRESS)) { |
| __fortify_fatal("scanf 'm' makes no sense with '*'"); |
| } |
| |
| /* |
| * 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 & LONG) { |
| if (flags & ALLOCATE) { |
| allocation = wcp = reinterpret_cast<wchar_t*>(malloc(width * sizeof(wchar_t))); |
| if (allocation == nullptr) goto allocation_failure; |
| } else if (flags & SUPPRESS) { |
| wcp = nullptr; |
| } else { |
| wcp = va_arg(ap, wchar_t*); |
| } |
| size_t bytes = 0; |
| while (width != 0) { |
| if (bytes == MB_CUR_MAX) { |
| fp->_flags |= __SERR; |
| goto input_failure; |
| } |
| buf[bytes++] = *fp->_p; |
| fp->_p++; |
| fp->_r--; |
| memset(&mbs, 0, sizeof(mbs)); |
| nconv = mbrtowc(wcp, buf, bytes, &mbs); |
| if (nconv == BIONIC_MULTIBYTE_RESULT_ILLEGAL_SEQUENCE) { |
| fp->_flags |= __SERR; |
| goto input_failure; |
| } |
| if (nconv == 0 && !(flags & SUPPRESS)) *wcp = L'\0'; |
| if (nconv != BIONIC_MULTIBYTE_RESULT_INCOMPLETE_SEQUENCE) { |
| nread += bytes; |
| width--; |
| if (!(flags & SUPPRESS)) wcp++; |
| bytes = 0; |
| } |
| if (fp->_r <= 0 && __srefill(fp)) { |
| if (bytes != 0) { |
| fp->_flags |= __SERR; |
| goto input_failure; |
| } |
| break; |
| } |
| } |
| if (allocation != nullptr) { |
| *va_arg(ap, wchar_t**) = reinterpret_cast<wchar_t*>(allocation); |
| allocation = nullptr; |
| } |
| if (!(flags & SUPPRESS)) nassigned++; |
| } else 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 { |
| if (flags & ALLOCATE) { |
| allocation = p = reinterpret_cast<char*>(malloc(width)); |
| if (allocation == nullptr) goto allocation_failure; |
| } else { |
| p = va_arg(ap, char*); |
| } |
| size_t r = fread(p, 1, width, fp); |
| if (r == 0) goto input_failure; |
| if (allocation != nullptr) { |
| *va_arg(ap, char**) = reinterpret_cast<char*>(allocation); |
| allocation = nullptr; |
| } |
| nread += r; |
| nassigned++; |
| } |
| break; |
| |
| case CT_CCL: |
| case CT_STRING: |
| // CT_CCL: scan a (nonempty) character class (sets NOSKIP). |
| // CT_STRING: like CCL, but zero-length string OK, & no NOSKIP. |
| if (width == 0) width = SIZE_MAX; |
| if (flags & LONG) { |
| // TODO: since no-one cares, replace this with a simple fgetwc loop? |
| n = 0; |
| if (flags & ALLOCATE) { |
| capacity = MIN(width, 32); |
| allocation = wcp = reinterpret_cast<wchar_t*>(malloc(sizeof(wchar_t) * capacity)); |
| if (allocation == nullptr) goto allocation_failure; |
| } else if (flags & SUPPRESS) { |
| wcp = nullptr; |
| } else { |
| wcp = va_arg(ap, wchar_t*); |
| } |
| size_t bytes = 0; |
| while ((c == CT_CCL || !isspace(*fp->_p)) && width != 0) { |
| if (bytes == MB_CUR_MAX) { |
| fp->_flags |= __SERR; |
| goto input_failure; |
| } |
| buf[bytes++] = *fp->_p; |
| fp->_p++; |
| fp->_r--; |
| wchar_t wc = L'\0'; |
| memset(&mbs, 0, sizeof(mbs)); |
| nconv = mbrtowc(&wc, buf, bytes, &mbs); |
| if (nconv == BIONIC_MULTIBYTE_RESULT_ILLEGAL_SEQUENCE) { |
| fp->_flags |= __SERR; |
| goto input_failure; |
| } |
| if (nconv != BIONIC_MULTIBYTE_RESULT_INCOMPLETE_SEQUENCE) { |
| if ((c == CT_CCL && wctob(wc) != EOF && !ccltab[wctob(wc)]) || (c == CT_STRING && iswspace(wc))) { |
| while (bytes != 0) { |
| bytes--; |
| ungetc(buf[bytes], fp); |
| } |
| break; |
| } |
| if (wcp) wcp[n] = wc; |
| n++; |
| if (allocation != nullptr && n == capacity) { |
| capacity *= 2; |
| wchar_t* new_allocation = |
| reinterpret_cast<wchar_t*>(realloc(allocation, sizeof(wchar_t) * capacity)); |
| if (new_allocation == nullptr) goto allocation_failure; |
| allocation = wcp = new_allocation; |
| } |
| nread += bytes; |
| width--; |
| bytes = 0; |
| } |
| if (fp->_r <= 0 && __srefill(fp)) { |
| if (bytes != 0) { |
| fp->_flags |= __SERR; |
| goto input_failure; |
| } |
| break; |
| } |
| } |
| if (c == CT_CCL && bytes != 0) { |
| fp->_flags |= __SERR; |
| goto input_failure; |
| } |
| if (allocation != nullptr) { |
| *va_arg(ap, wchar_t**) = reinterpret_cast<wchar_t*>(allocation); |
| allocation = nullptr; |
| } |
| } else 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 (c == CT_CCL && n == 0) goto input_failure; |
| break; |
| } |
| } |
| nread += n; |
| } else { |
| if (flags & ALLOCATE) { |
| capacity = MIN(width, 32); |
| allocation = p = reinterpret_cast<char*>(malloc(capacity)); |
| if (allocation == nullptr) goto allocation_failure; |
| } else { |
| p = va_arg(ap, char*); |
| } |
| n = 0; |
| while (ccltab[*fp->_p]) { |
| fp->_r--; |
| p[n++] = *fp->_p++; |
| if (allocation != nullptr && n == capacity) { |
| capacity *= 2; |
| char* new_allocation = reinterpret_cast<char*>(realloc(allocation, capacity)); |
| if (new_allocation == nullptr) goto allocation_failure; |
| allocation = p = new_allocation; |
| } |
| if (--width == 0) break; |
| if (fp->_r <= 0 && __srefill(fp)) { |
| if (c == CT_CCL && n == 0) goto input_failure; |
| break; |
| } |
| } |
| nread += n; |
| if (allocation != nullptr) { |
| *va_arg(ap, char**) = reinterpret_cast<char*>(allocation); |
| allocation = nullptr; |
| } |
| } |
| if (c == CT_CCL && n == 0) goto match_failure; |
| if (!(flags & SUPPRESS)) { |
| if (flags & LONG) { |
| wcp[n] = L'\0'; |
| } else { |
| p[n] = '\0'; |
| } |
| ++nassigned; |
| } |
| break; |
| |
| 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 0b/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 |= PFBOK | PFXOK; |
| } |
| if (flags & NZDIGITS) { |
| flags &= ~(SIGNOK | NZDIGITS | NDIGITS); |
| } else { |
| flags &= ~(SIGNOK | PFBOK | PFXOK | NDIGITS); |
| } |
| goto ok; |
| case 'B': |
| case 'b': |
| // Is this 'b' or 'B' potentially part of an "0b" prefix? |
| if ((flags & PFBOK) && p == buf + 1 + !!(flags & HAVESIGN)) { |
| base = 2; |
| flags &= ~PFBOK; |
| goto ok; |
| } |
| // No? Fall through and see if it's a hex digit instead then... |
| __BIONIC_FALLTHROUGH; |
| case '1': |
| case '2': |
| case '3': |
| case '4': |
| case '5': |
| case '6': |
| case '7': |
| case '8': |
| case '9': |
| case 'A': |
| case 'C': |
| case 'D': |
| case 'E': |
| case 'F': |
| case 'a': |
| case 'c': |
| case 'd': |
| case 'e': |
| case 'f': |
| if (base == 0) base = 10; |
| if (base != 16 && (c - '0') >= base) break; /* not legal here */ |
| flags &= ~(SIGNOK | PFBOK | 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 was `[-+]0[BbXx]`, push back and treat it |
| * as `[-+]0`. |
| */ |
| if (flags & NDIGITS) { |
| if (p > buf) ungetc(*reinterpret_cast<u_char*>(--p), fp); |
| goto match_failure; |
| } |
| c = reinterpret_cast<u_char*>(p)[-1]; |
| if ((base == 2 && (c == 'b' || c == 'B')) || c == 'x' || c == 'X') { |
| --p; |
| (void)ungetc(c, fp); |
| } |
| if ((flags & SUPPRESS) == 0) { |
| uintmax_t res; |
| |
| *p = '\0'; |
| if (flags & UNSIGNED) { |
| res = strtoumax(buf, nullptr, base); |
| } else { |
| res = strtoimax(buf, nullptr, base); |
| } |
| if (flags & POINTER) { |
| *va_arg(ap, void**) = reinterpret_cast<void*>(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; |
| |
| case CT_FLOAT: |
| /* scan a floating point number as if by strtod */ |
| if (width == 0 || width > sizeof(buf) - 1) width = sizeof(buf) - 1; |
| if ((width = parsefloat(fp, buf, buf + width)) == 0) goto match_failure; |
| if ((flags & SUPPRESS) == 0) { |
| if (flags & LONGDBL) { |
| long double res = strtold(buf, &p); |
| *va_arg(ap, long double*) = res; |
| } else if (flags & LONG) { |
| double res = strtod(buf, &p); |
| *va_arg(ap, double*) = res; |
| } else { |
| float res = strtof(buf, &p); |
| *va_arg(ap, float*) = res; |
| } |
| if (static_cast<size_t>(p - buf) != width) abort(); |
| nassigned++; |
| } |
| nread += width; |
| break; |
| } |
| } |
| allocation_failure: |
| input_failure: |
| free(allocation); |
| if (nassigned == 0) 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 const unsigned char* __sccl(char* tab, const unsigned 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 */ |
| } |
| memset(tab, v, 256); |
| 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 */ |
| } |
