vfscanf.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
* Copyright (c) 2000-2001, 2004 Sendmail, Inc. and its suppliers.
* All rights reserved.
* 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.
*
* By using this file, you agree to the terms and conditions set
* forth in the LICENSE file which can be found at the top level of
* the sendmail distribution.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <sm/gen.h>
SM_IDSTR(id, "@(#)$Id: vfscanf.c,v 1.52 2004/08/03 20:56:32 ca Exp $")
#include <ctype.h>
#include <stdlib.h>
#include <errno.h>
#include <setjmp.h>
#include <sys/time.h>
#include <sm/varargs.h>
#include <sm/config.h>
#include <sm/io.h>
#include <sm/signal.h>
#include <sm/clock.h>
#include <sm/string.h>
#include "local.h"
#define BUF 513 /* Maximum length of numeric string. */
/* Flags used during conversion. */
#define LONG 0x01 /* l: long or double */
#define SHORT 0x04 /* h: short */
#define QUAD 0x08 /* q: quad (same as ll) */
#define SUPPRESS 0x10 /* suppress assignment */
#define POINTER 0x20 /* weird %p pointer (`fake hex') */
#define NOSKIP 0x40 /* 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 0x080 /* +/- is (still) legal */
#define NDIGITS 0x100 /* no digits detected */
#define DPTOK 0x200 /* (float) decimal point is still legal */
#define EXPOK 0x400 /* (float) exponent (e+3, etc) still legal */
#define PFXOK 0x200 /* 0x prefix is (still) legal */
#define NZDIGITS 0x400 /* 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., strtoll or strtoull */
#define CT_FLOAT 4 /* floating, i.e., strtod */
static void scanalrm __P((int));
static unsigned char *sm_sccl __P((char *, unsigned char *));
static jmp_buf ScanTimeOut;
/*
** SCANALRM -- handler when timeout activated for sm_io_vfscanf()
**
** Returns flow of control to where setjmp(ScanTimeOut) was set.
**
** Parameters:
** sig -- unused
**
** Returns:
** does not return
**
** Side Effects:
** returns flow of control to setjmp(ScanTimeOut).
**
** NOTE: THIS CAN BE CALLED FROM A SIGNAL HANDLER. DO NOT ADD
** ANYTHING TO THIS ROUTINE UNLESS YOU KNOW WHAT YOU ARE
** DOING.
*/
/* ARGSUSED0 */
static void
scanalrm(sig)
int sig;
{
longjmp(ScanTimeOut, 1);
}
/*
** SM_VFSCANF -- convert input into data units
**
** Parameters:
** fp -- file pointer for input data
** timeout -- time intvl allowed to complete (milliseconds)
** fmt0 -- format for finding data units
** ap -- vectors for memory location for storing data units
**
** Results:
** Success: number of data units assigned
** Failure: SM_IO_EOF
*/
int
sm_vfscanf(fp, timeout, fmt0, ap)
register SM_FILE_T *fp;
int SM_NONVOLATILE timeout;
char const *fmt0;
va_list SM_NONVOLATILE ap;
{
register unsigned char *SM_NONVOLATILE fmt = (unsigned 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 strtoll/strtoull */
ULONGLONG_T (*ccfn)(); /* conversion function (strtoll/strtoull) */
char ccltab[256]; /* character class table for %[...] */
char buf[BUF]; /* buffer for numeric conversions */
SM_EVENT *evt = NULL;
/* `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 };
if (timeout == SM_TIME_DEFAULT)
timeout = fp->f_timeout;
if (timeout == SM_TIME_IMMEDIATE)
{
/*
** Filling the buffer will take time and we are wanted to
** return immediately. So...
*/
errno = EAGAIN;
return SM_IO_EOF;
}
if (timeout != SM_TIME_FOREVER)
{
if (setjmp(ScanTimeOut) != 0)
{
errno = EAGAIN;
return SM_IO_EOF;
}
evt = sm_seteventm(timeout, scanalrm, 0);
}
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)
{
if (evt != NULL)
sm_clrevent(evt); /* undo our timeout */
return nassigned;
}
if (isspace(c))
{
while ((fp->f_r > 0 || sm_refill(fp, SM_TIME_FOREVER)
== 0) &&
isspace(*fp->f_p))
nread++, fp->f_r--, fp->f_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->f_r <= 0 && sm_refill(fp, SM_TIME_FOREVER))
goto input_failure;
if (*fp->f_p != c)
goto match_failure;
fp->f_r--, fp->f_p++;
nread++;
continue;
case '*':
flags |= SUPPRESS;
goto again;
case 'h':
flags |= SHORT;
goto again;
case 'l':
if (*fmt == 'l')
{
fmt++;
flags |= QUAD;
}
else
{
flags |= LONG;
}
goto again;
case 'q':
flags |= QUAD;
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 = (ULONGLONG_T (*)())sm_strtoll;
base = 10;
break;
case 'i':
c = CT_INT;
ccfn = (ULONGLONG_T (*)())sm_strtoll;
base = 0;
break;
case 'O': /* compat */
flags |= LONG;
/* FALLTHROUGH */
case 'o':
c = CT_INT;
ccfn = sm_strtoull;
base = 8;
break;
case 'u':
c = CT_INT;
ccfn = sm_strtoull;
base = 10;
break;
case 'X':
case 'x':
flags |= PFXOK; /* enable 0x prefixing */
c = CT_INT;
ccfn = sm_strtoull;
base = 16;
break;
case 'E':
case 'G':
case 'e':
case 'f':
case 'g':
c = CT_FLOAT;
break;
case 's':
c = CT_STRING;
break;
case '[':
fmt = sm_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 = sm_strtoull;
base = 16;
break;
case 'n':
if (flags & SUPPRESS) /* ??? */
continue;
if (flags & SHORT)
*SM_VA_ARG(ap, short *) = nread;
else if (flags & LONG)
*SM_VA_ARG(ap, long *) = nread;
else
*SM_VA_ARG(ap, int *) = nread;
continue;
/* Disgusting backwards compatibility hacks. XXX */
case '\0': /* compat */
if (evt != NULL)
sm_clrevent(evt); /* undo our timeout */
return SM_IO_EOF;
default: /* compat */
if (isupper(c))
flags |= LONG;
c = CT_INT;
ccfn = (ULONGLONG_T (*)()) sm_strtoll;
base = 10;
break;
}
/* We have a conversion that requires input. */
if (fp->f_r <= 0 && sm_refill(fp, SM_TIME_FOREVER))
goto input_failure;
/*
** Consume leading white space, except for formats
** that suppress this.
*/
if ((flags & NOSKIP) == 0)
{
while (isspace(*fp->f_p))
{
nread++;
if (--fp->f_r > 0)
fp->f_p++;
else if (sm_refill(fp, SM_TIME_FOREVER))
goto input_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)
width = 1;
if (flags & SUPPRESS)
{
size_t sum = 0;
for (;;)
{
if ((size_t) (n = fp->f_r) < width)
{
sum += n;
width -= n;
fp->f_p += n;
if (sm_refill(fp,
SM_TIME_FOREVER))
{
if (sum == 0)
goto input_failure;
break;
}
}
else
{
sum += width;
fp->f_r -= width;
fp->f_p += width;
break;
}
}
nread += sum;
}
else
{
size_t r;
r = sm_io_read(fp, SM_TIME_FOREVER,
(void *) SM_VA_ARG(ap, char *),
width);
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->f_p] != '\0')
{
n++, fp->f_r--, fp->f_p++;
if (--width == 0)
break;
if (fp->f_r <= 0 &&
sm_refill(fp, SM_TIME_FOREVER))
{
if (n == 0) /* XXX how? */
goto input_failure;
break;
}
}
if (n == 0)
goto match_failure;
}
else
{
p0 = p = SM_VA_ARG(ap, char *);
while (ccltab[*fp->f_p] != '\0')
{
fp->f_r--;
*p++ = *fp->f_p++;
if (--width == 0)
break;
if (fp->f_r <= 0 &&
sm_refill(fp, SM_TIME_FOREVER))
{
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->f_p))
{
n++, fp->f_r--, fp->f_p++;
if (--width == 0)
break;
if (fp->f_r <= 0 &&
sm_refill(fp, SM_TIME_FOREVER))
break;
}
nread += n;
}
else
{
p0 = p = SM_VA_ARG(ap, char *);
while (!isspace(*fp->f_p))
{
fp->f_r--;
*p++ = *fp->f_p++;
if (--width == 0)
break;
if (fp->f_r <= 0 &&
sm_refill(fp, SM_TIME_FOREVER))
break;
}
*p = 0;
nread += p - p0;
nassigned++;
}
continue;
case CT_INT:
/* scan an integer as if by strtoll/strtoull */
#if SM_CONF_BROKEN_SIZE_T
if (width == 0 || width > sizeof(buf) - 1)
width = sizeof(buf) - 1;
#else /* SM_CONF_BROKEN_SIZE_T */
/* size_t is unsigned, hence this optimisation */
if (--width > sizeof(buf) - 2)
width = sizeof(buf) - 2;
width++;
#endif /* SM_CONF_BROKEN_SIZE_T */
flags |= SIGNOK | NDIGITS | NZDIGITS;
for (p = buf; width > 0; width--)
{
c = *fp->f_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->f_r > 0)
fp->f_p++;
else if (sm_refill(fp, SM_TIME_FOREVER))
break; /* SM_IO_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) sm_io_ungetc(fp, SM_TIME_DEFAULT,
*(unsigned char *)--p);
goto match_failure;
}
c = ((unsigned char *)p)[-1];
if (c == 'x' || c == 'X')
{
--p;
(void) sm_io_ungetc(fp, SM_TIME_DEFAULT, c);
}
if ((flags & SUPPRESS) == 0)
{
ULONGLONG_T res;
*p = 0;
res = (*ccfn)(buf, (char **)NULL, base);
if (flags & POINTER)
*SM_VA_ARG(ap, void **) =
(void *)(long) res;
else if (flags & QUAD)
*SM_VA_ARG(ap, LONGLONG_T *) = res;
else if (flags & LONG)
*SM_VA_ARG(ap, long *) = res;
else if (flags & SHORT)
*SM_VA_ARG(ap, short *) = res;
else
*SM_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;
flags |= SIGNOK | NDIGITS | DPTOK | EXPOK;
for (p = buf; width; width--)
{
c = *fp->f_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->f_r > 0)
fp->f_p++;
else if (sm_refill(fp, SM_TIME_FOREVER))
break; /* SM_IO_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)
(void) sm_io_ungetc(fp,
SM_TIME_DEFAULT,
*(unsigned char *)--p);
goto match_failure;
}
/* just a bad exponent (e and maybe sign) */
c = *(unsigned char *) --p;
if (c != 'e' && c != 'E')
{
(void) sm_io_ungetc(fp, SM_TIME_DEFAULT,
c); /* sign */
c = *(unsigned char *)--p;
}
(void) sm_io_ungetc(fp, SM_TIME_DEFAULT, c);
}
if ((flags & SUPPRESS) == 0)
{
double res;
*p = 0;
res = strtod(buf, (char **) NULL);
if (flags & LONG)
*SM_VA_ARG(ap, double *) = res;
else
*SM_VA_ARG(ap, float *) = res;
nassigned++;
}
nread += p - buf;
break;
}
}
input_failure:
if (evt != NULL)
sm_clrevent(evt); /* undo our timeout */
return nassigned ? nassigned : -1;
match_failure:
if (evt != NULL)
sm_clrevent(evt); /* undo our timeout */
return nassigned;
}
/*
** SM_SCCL -- sequenced character comparison list
**
** 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.
**
** Parameters:
** tab -- array flagging "active" char's to match (returned)
** fmt -- character list (within "[]")
**
** Results:
*/
static unsigned char *
sm_sccl(tab, fmt)
register char *tab;
register unsigned 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;
break;
#endif
case ']': /* end of scanset */
return fmt;
default: /* just another character */
c = n;
break;
}
}
/* NOTREACHED */
}