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This commit was manufactured by cvs2svn to create tag 'FreeBSD-release/1.0'.
[unix-history] / gnu / lib / libg++ / iostream / sbufvscan.C
/*
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley. The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
// Extensively hacked for GNU iostream by Per Bothner 1991, 1992.
// Changes copyright Per Bothner 1992.
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "%W% (Berkeley) %G%";
#endif /* LIBC_SCCS and not lint */
#include <ioprivate.h>
#include <ctype.h>
#ifndef NO_STDARG
#include <stdarg.h>
#else
#include <varargs.h>
#endif
#ifndef NO_FLOATING_POINT
#define FLOATING_POINT
#endif
#ifdef FLOATING_POINT
#include "floatio.h"
#define BUF (MAXEXP+MAXFRACT+3) /* 3 = sign + decimal point + NUL */
#else
#define BUF 40
#endif
/*
* 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
extern "C" u_long strtoul(const char*, char**, int);
static const u_char *__sccl(register char *tab, register const u_char *fmt);
// If state is non-NULL, set failbit and/or eofbit as appropriate.
int streambuf::vscan(char const *fmt0,
_G_va_list ap,
ios *stream /* = NULL */)
{
register const u_char *fmt = (const 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 */
// Assignments to base and ccfn are just to suppress warnings from gcc.
int base = 0; /* base argument to strtol/strtoul */
typedef u_long (*strtoulfn)(const char*, char**, int);
strtoulfn ccfn = 0;
// conversion function (strtol/strtoul)
char ccltab[256]; /* character class table for %[...] */
char buf[BUF]; /* buffer for numeric conversions */
int seen_eof = 0;
/* `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;
for (;;) {
c = *fmt++;
if (c == 0)
goto done;
if (isspace(c)) {
for (;;) {
c = sbumpc();
if (c == EOF)
goto eof_failure;
if (!isspace(c)) {
sputbackc(c);
break;
}
nread++;
}
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:
n = sbumpc();
if (n == EOF)
goto eof_failure;
if (n != c) {
sputbackc(n);
goto match_failure;
}
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 = (strtoulfn)strtol;
base = 10;
break;
case 'i':
c = CT_INT;
ccfn = (strtoulfn)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':
case 'x':
flags |= PFXOK; /* enable 0x prefixing */
c = CT_INT;
ccfn = strtoul;
base = 16;
break;
#ifdef FLOATING_POINT
case 'E': case 'F':
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 */
nassigned = EOF;
goto done;
default: /* compat */
if (isupper(c))
flags |= LONG;
c = CT_INT;
ccfn = (strtoulfn)strtol;
base = 10;
break;
}
/*
* We have a conversion that requires input.
*/
if (sgetc() == EOF)
goto eof_failure;
/*
* Consume leading white space, except for formats
* that suppress this.
*/
if ((flags & NOSKIP) == 0) {
n = (unsigned char)*_gptr;
while (isspace(n)) {
_gptr++;
nread++;
n = sgetc();
if (n == EOF)
goto eof_failure;
}
// Note that there is at least one character in
// the buffer, so conversions that do not set NOSKIP
// can no longer result in an input failure.
}
/*
* Do the conversion.
*/
switch (c) {
case CT_CHAR:
/* scan arbitrary characters (sets NOSKIP) */
if (width == 0) // FIXME!
width = 1;
if (flags & SUPPRESS) {
size_t sum = 0;
for (;;) {
if ((n = _egptr - _gptr) < (int)width) {
sum += n;
width -= n;
_gptr += n;
if (underflow() == EOF)
if (sum == 0)
goto eof_failure;
else {
seen_eof++;
break;
}
} else {
sum += width;
_gptr += width;
break;
}
}
nread += sum;
} else {
size_t r = sgetn((char*)va_arg(ap, char*),
width);
if (r != width)
goto eof_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[(unsigned char)*_gptr]) {
n++, _gptr++;
if (--width == 0)
break;
if (sgetc() == EOF) {
if (n == 0)
goto eof_failure;
seen_eof++;
break;
}
}
if (n == 0)
goto match_failure;
} else {
p0 = p = va_arg(ap, char *);
while (ccltab[(unsigned char)*_gptr]) {
*p++ = *_gptr++;
if (--width == 0)
break;
if (sgetc() == EOF) {
if (p == p0)
goto eof_failure;
seen_eof++;
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((unsigned char)*_gptr)) {
n++, _gptr++;
if (--width == 0)
break;
if (sgetc() == EOF) {
seen_eof++;
break;
}
}
nread += n;
} else {
p0 = p = va_arg(ap, char *);
while (!isspace((unsigned char)*_gptr)) {
*p++ = *_gptr++;
if (--width == 0)
break;
if (sgetc() == EOF) {
seen_eof++;
break;
}
}
*p = 0;
nread += p - p0;
nassigned++;
}
continue;
case CT_INT:
/* scan an integer as if by strtol/strtoul */
if (width == 0 || width > sizeof(buf) - 1)
width = sizeof(buf) - 1;
flags |= SIGNOK | NDIGITS | NZDIGITS;
for (p = buf; width; width--) {
c = (unsigned char)*_gptr;
/*
* 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;
_gptr++;
if (sgetc() == EOF) {
seen_eof++;
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) sputbackc(*(u_char *)--p);
goto match_failure;
}
c = ((u_char *)p)[-1];
if (c == 'x' || c == 'X') {
--p;
(void) sputbackc(c);
}
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 */
if (width == 0 || width > sizeof(buf) - 1)
width = sizeof(buf) - 1;
flags |= SIGNOK | NDIGITS | DPTOK | EXPOK;
for (p = buf; width; width--) {
c = (unsigned char)*_gptr;
/*
* 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;
_gptr++;
if (sgetc() == EOF) {
seen_eof++;
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)
sputbackc(*(u_char *)--p);
goto match_failure;
}
/* just a bad exponent (e and maybe sign) */
c = *(u_char *)--p;
if (c != 'e' && c != 'E') {
(void)sputbackc(c);/* sign */
c = *(u_char *)--p;
}
(void) sputbackc(c);
}
if ((flags & SUPPRESS) == 0) {
double res;
*p = 0;
#ifdef USE_DTOA
res = strtod(buf, NULL);
#else
res = atof(buf);
#endif
if (flags & LONG)
*va_arg(ap, double *) = res;
else
*va_arg(ap, float *) = res;
nassigned++;
}
nread += p - buf;
break;
#endif /* FLOATING_POINT */
}
}
eof_failure:
seen_eof++;
input_failure:
if (nassigned == 0)
nassigned = -1;
match_failure:
if (stream)
stream->set(ios::failbit);
done:
if (stream && seen_eof)
stream->set(ios::eofbit);
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 u_char *__sccl(register char *tab, register const 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 */
}
int streambuf::scan(char const *format ...)
{
va_list ap;
va_start(ap, format);
int count = vscan(format, ap);
va_end(ap);
return count;
}
Continuous source code history from original PDP-7 UNIX to FreeBSD 2, the first fully unencumbered FreeBSD release.