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-rw-r--r--lib/libc/stdio/vfscanf.c748
1 files changed, 748 insertions, 0 deletions
diff --git a/lib/libc/stdio/vfscanf.c b/lib/libc/stdio/vfscanf.c
new file mode 100644
index 0000000..22ed5a0
--- /dev/null
+++ b/lib/libc/stdio/vfscanf.c
@@ -0,0 +1,748 @@
+/*-
+ * 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. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. 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.
+ */
+
+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "@(#)vfscanf.c 8.1 (Berkeley) 6/4/93";
+#endif /* LIBC_SCCS and not lint */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <ctype.h>
+#if __STDC__
+#include <stdarg.h>
+#else
+#include <varargs.h>
+#endif
+#include "local.h"
+
+#define FLOATING_POINT
+
+#include "floatio.h"
+#define BUF 513 /* Maximum length of numeric string. */
+
+/*
+ * Flags used during conversion.
+ */
+#define LONG 0x01 /* l: long or double */
+#define LONGDBL 0x02 /* L: long double; unimplemented */
+#define SHORT 0x04 /* h: short */
+#define SUPPRESS 0x08 /* suppress assignment */
+#define POINTER 0x10 /* weird %p pointer (`fake hex') */
+#define NOSKIP 0x20 /* do not skip blanks */
+
+/*
+ * The following are used in numeric conversions only:
+ * SIGNOK, NDIGITS, DPTOK, and EXPOK are for floating point;
+ * SIGNOK, NDIGITS, PFXOK, and NZDIGITS are for integral.
+ */
+#define SIGNOK 0x40 /* +/- is (still) legal */
+#define NDIGITS 0x80 /* no digits detected */
+
+#define DPTOK 0x100 /* (float) decimal point is still legal */
+#define EXPOK 0x200 /* (float) exponent (e+3, etc) still legal */
+
+#define PFXOK 0x100 /* 0x prefix is (still) legal */
+#define NZDIGITS 0x200 /* 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., strtol or strtoul */
+#define CT_FLOAT 4 /* floating, i.e., strtod */
+
+#define u_char unsigned char
+#define u_long unsigned long
+
+static u_char *__sccl();
+
+/*
+ * vfscanf
+ */
+__svfscanf(fp, fmt0, ap)
+ register FILE *fp;
+ char const *fmt0;
+ va_list ap;
+{
+ register u_char *fmt = (u_char *)fmt0;
+ register int c; /* character from format, or conversion */
+ register size_t width; /* field width, or 0 */
+ register char *p; /* points into all kinds of strings */
+ register int n; /* handy integer */
+ register int flags; /* flags as defined above */
+ register 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 strtol/strtoul */
+ u_long (*ccfn)(); /* conversion function (strtol/strtoul) */
+ 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 };
+
+ nassigned = 0;
+ nread = 0;
+ base = 0; /* XXX just to keep gcc happy */
+ ccfn = NULL; /* XXX just to keep gcc happy */
+ for (;;) {
+ c = *fmt++;
+ if (c == 0)
+ return (nassigned);
+ if (isspace(c)) {
+ for (;;) {
+ if (fp->_r <= 0 && __srefill(fp))
+ return (nassigned);
+ if (!isspace(*fp->_p))
+ break;
+ 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 'l':
+ flags |= LONG;
+ goto again;
+ case 'L':
+ flags |= LONGDBL;
+ goto again;
+ case 'h':
+ flags |= SHORT;
+ 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;
+ ccfn = (u_long (*)())strtol;
+ base = 10;
+ break;
+
+ case 'i':
+ c = CT_INT;
+ ccfn = (u_long (*)())strtol;
+ base = 0;
+ break;
+
+ case 'O': /* compat */
+ flags |= LONG;
+ /* FALLTHROUGH */
+ case 'o':
+ c = CT_INT;
+ ccfn = strtoul;
+ base = 8;
+ break;
+
+ case 'u':
+ c = CT_INT;
+ ccfn = strtoul;
+ base = 10;
+ break;
+
+ case 'X': /* compat XXX */
+ flags |= LONG;
+ /* FALLTHROUGH */
+ case 'x':
+ flags |= PFXOK; /* enable 0x prefixing */
+ c = CT_INT;
+ ccfn = strtoul;
+ base = 16;
+ break;
+
+#ifdef FLOATING_POINT
+ case 'E': /* compat XXX */
+ case 'F': /* compat */
+ flags |= LONG;
+ /* FALLTHROUGH */
+ 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;
+ ccfn = strtoul;
+ base = 16;
+ break;
+
+ case 'n':
+ if (flags & SUPPRESS) /* ??? */
+ continue;
+ if (flags & SHORT)
+ *va_arg(ap, short *) = nread;
+ else if (flags & LONG)
+ *va_arg(ap, long *) = 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;
+ ccfn = (u_long (*)())strtol;
+ 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 = ~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 = ~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 strtol/strtoul */
+#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;
+ goto ok;
+ }
+ break;
+
+ /* x ok iff flag still set & 2nd char */
+ case 'x': case 'X':
+ if (flags & PFXOK && p == buf + 1) {
+ 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) {
+ u_long res;
+
+ *p = 0;
+ res = (*ccfn)(buf, (char **)NULL, base);
+ if (flags & POINTER)
+ *va_arg(ap, void **) = (void *)res;
+ else if (flags & SHORT)
+ *va_arg(ap, short *) = res;
+ else if (flags & LONG)
+ *va_arg(ap, long *) = 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 & 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(tab, fmt)
+ register char *tab;
+ register u_char *fmt;
+{
+ register 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 */
+}
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