nuttx/libs/libc/stdio/lib_libvscanf.c
2019-02-15 18:26:06 -06:00

1213 lines
36 KiB
C

/****************************************************************************
* libs/libc/stdio/lib_libsscanf.c
*
* Copyright (C) 2007, 2008, 2011-2014, 2016, 2019 Gregory Nutt. All rights
* reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
* Johannes Schock
*
* 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 NuttX 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 COPYRIGHT HOLDERS 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
* COPYRIGHT OWNER 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/compiler.h>
#include <sys/types.h>
#include <stdarg.h>
#include <stdlib.h>
#include <stdbool.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/streams.h>
#include "libc.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#define MAXLN 128
#define HH_MOD -2
#define H_MOD -1
#define NO_MOD 0
#define L_MOD 1
#define LL_MOD 2
#ifndef MIN
# define MIN(a,b) (((a) < (b)) ? (a) : (b))
#endif
#ifndef MAX
# define MAX(a,b) (((a) > (b)) ? (a) : (b))
#endif
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: findscanset
*
* Description:
* Fill in the given table from the scanset at the given format.
* Return a pointer to the character the closing ']'.
* The table has a 1 wherever characters should be considered part of the
* scanset.
*
* Function findscanset based on source function __sccl of FreeBSD
* (https://github.com/lattera/freebsd/blob/master/sys/kern/subr_scanf.c)
*
****************************************************************************/
#ifdef CONFIG_LIBC_SCANSET
static FAR const char *findscanset(FAR const char *fmt,
FAR unsigned char set[32])
{
int c;
int n;
int v;
int i;
fmt++; /* Skip '[' */
/* 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(set, 0, 32);
if (c == 0)
{
goto doexit;
}
/* 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 '-'.
*/
for (; ; )
{
set[c / 8] |= (1 << (c % 8)); /* Take character c */
doswitch:n = *fmt++; /* Examine the next */
switch (n)
{
case 0: /* Format ended too soon */
case ']': /* End of scanset */
goto doexit;
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 */
c++;
set[c / 8] |= (1 << (c % 8)); /* Take character c */
}
while (c < n);
/* 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;
default: /* Just another character */
c = n;
break;
}
}
doexit:
if (v) /* Default => accept */
{
for (i = 0; i < 32; i++) /* Invert all */
{
set[i] ^= 0xff;
}
}
return (fmt - 1);
}
#endif
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: lib_vscanf
*
* Description:
* Stream-oriented implementation that underlies scanf family: scanf,
* fscanf, vfscanf, sscanf, and vsscanf
*
****************************************************************************/
int lib_vscanf(FAR struct lib_instream_s *obj, FAR int *lastc,
FAR const IPTR char *fmt, va_list ap)
{
int c;
FAR char *tv;
FAR const char *tc;
int modifier;
bool noassign;
bool conv;
int assigncount;
int count;
int ngetstart;
int width;
int fwidth;
int base = 10;
char tmp[MAXLN];
#ifdef CONFIG_LIBC_LONG_LONG
FAR unsigned long long *plonglong = NULL;
#endif
FAR unsigned long *plong = NULL;
FAR unsigned int *pint = NULL;
FAR unsigned short *pshort = NULL;
FAR unsigned char *pchar = NULL;
#ifdef CONFIG_LIBC_SCANSET
unsigned char set[32]; /* Bit field (256 / 8) */
#endif
/* keep this for future reference linfo("buf=\"%s\" fmt=\"%s\"\n", buf, fmt); */
/* Parse the format, extracting values from the input buffer as needed */
assigncount = 0;
count = 0;
width = 0;
conv = false;
noassign = false;
modifier = NO_MOD;
ngetstart = obj->nget; /* for %n calculations */
/* Make sure lastc is not NULL. */
if (lastc == NULL)
{
lastc = &c;
}
/* Loop until all characters in the fmt string have been processed. We may
* have to continue loop after reaching the end the input data in order to
* handle trailing %n format specifiers.
*/
/* Get first character, we keep always the next character in c */
c = obj->get(obj);
while (*fmt)
{
/* Skip over white spaces */
if (isspace(*fmt))
{
while (isspace(c))
{
c = obj->get(obj);
}
}
while (isspace(*fmt))
{
fmt++;
}
/* Check for a conversion specifier */
if (*fmt == '%')
{
linfo("Specifier found\n");
/* Check for qualifiers on the conversion specifier */
fmt++;
for (; *fmt; fmt++)
{
linfo("Processing %c\n", *fmt);
#ifdef CONFIG_LIBC_SCANSET
if (strchr("dibouxXcseEfFgGaAn[%", *fmt))
#else
if (strchr("dibouxXcseEfFgGaAn%", *fmt))
#endif
{
if (*fmt != '%')
{
conv = true;
}
break;
}
if (*fmt == '*')
{
noassign = true;
}
else if (*fmt == 'l' || *fmt == 'L')
{
modifier = L_MOD;
if (*(fmt + 1) == 'l' || *(fmt + 1) == 'L')
{
modifier = LL_MOD;
fmt++;
}
}
else if (*fmt == 'h' || *fmt == 'H')
{
modifier = H_MOD;
if (*(fmt + 1) == 'h' || *(fmt + 1) == 'H')
{
modifier = HH_MOD;
fmt++;
}
}
else if (*fmt >= '1' && *fmt <= '9')
{
for (tc = fmt; isdigit(*fmt); fmt++)
;
strncpy(tmp, tc, fmt - tc);
tmp[fmt - tc] = '\0';
width = atoi(tmp);
fmt--;
}
}
/* Process %s: String conversion */
if (*fmt == 's')
{
linfo("Performing string conversion\n");
/* Get a pointer to the char * value. We need to do this even
* of we have reached the end of the input data in order to
* update the 'ap' variable.
*/
tv = NULL; /* To avoid warnings about begin uninitialized */
if (!noassign)
{
tv = va_arg(ap, FAR char *);
tv[0] = '\0';
}
/* Skip over white space */
while (isspace(c))
{
c = obj->get(obj);
}
/* But we only perform the data conversion is we still have
* bytes remaining in the input data stream.
*/
if (c > 0)
{
/* Use the actual field's width if 1) no fieldwidth
* specified or 2) the actual field's width is smaller
* than fieldwidth specified.
*/
fwidth = 0;
while ((!width || (fwidth < width)) && (c > 0) &&
!isspace(c))
{
if (!noassign)
{
tv[fwidth] = c;
}
fwidth++;
c = obj->get(obj);
}
if (!noassign)
{
tv[fwidth] = '\0';
assigncount++;
}
count++;
}
}
#ifdef CONFIG_LIBC_SCANSET
/* Process %[: Scanset conversion */
if (*fmt == '[')
{
linfo("Performing scanset conversion\n");
fmt = findscanset(fmt, set); /* find scanset */
/* Get a pointer to the char * value. We need to do this even
* if we have reached the end of the input data in order to
* update the 'ap' variable.
*/
tv = NULL; /* To avoid warnings about begin uninitialized */
if (!noassign)
{
tv = va_arg(ap, FAR char *);
tv[0] = '\0';
}
/* But we only perform the data conversion is we still have
* bytes remaining in the input data stream.
*/
if (c > 0)
{
/* Use the actual field's width if 1) no fieldwidth
* specified or 2) the actual field's width is smaller
* than the fieldwidth specified.
*/
fwidth = 0;
while ((!width || (fwidth < width)) && (c > 0)
&& ((set[c / 8] & (1 << (c % 8))) != 0))
{
if (!noassign)
{
tv[fwidth] = c;
}
fwidth++;
c = obj->get(obj);
}
if (!fwidth)
{
*lastc = c;
return assigncount;
}
if (!noassign)
{
tv[fwidth] = '\0';
assigncount++;
}
count++;
}
}
#endif
/* Process %c: Character conversion */
else if (*fmt == 'c')
{
linfo("Performing character conversion\n");
/* Get a pointer to the char * value. We need to do this even
* if we have reached the end of the input data in order to
* update the 'ap' variable.
*/
tv = NULL; /* To avoid warnings about being uninitialized */
if (!noassign)
{
tv = va_arg(ap, FAR char *);
tv[0] = '\0';
}
/* But we only perform the data conversion is we still have
* bytes remaining in the input data stream.
*/
if (c > 0)
{
/* Was a field width specified? */
if (!width)
{
/* No, then width is this one single character */
width = 1;
}
/* Copy the character(s) (if we are making an assignment) */
fwidth = 0;
while ((fwidth < width) && c > 0)
{
if (!noassign)
{
tv[fwidth] = c;
}
fwidth++;
c = obj->get(obj);
}
if (fwidth != width)
{
*lastc = c;
return assigncount;
}
if (!noassign)
{
assigncount++;
}
count++;
}
}
/* Process %d, %o, %b, %x, %u: Various integer conversions */
else if (strchr("dobxXui", *fmt))
{
bool sign;
linfo("Performing integer conversion\n");
/* Get a pointer to the integer value. We need to do this even
* if we have reached the end of the input data in order to
* update the 'ap' variable.
*/
if (!noassign)
{
/* We have to check whether we need to return a long or an
* int.
*/
switch (modifier)
{
case HH_MOD:
pchar = va_arg(ap, FAR unsigned char *);
*pchar = 0;
break;
case H_MOD:
pshort = va_arg(ap, FAR unsigned short *);
*pshort = 0;
break;
case NO_MOD:
pint = va_arg(ap, FAR unsigned int *);
*pint = 0;
break;
default:
case L_MOD:
plong = va_arg(ap, FAR unsigned long *);
*plong = 0;
break;
#ifdef CONFIG_LIBC_LONG_LONG
case LL_MOD:
plonglong = va_arg(ap, FAR unsigned long long *);
*plonglong = 0;
break;
#endif
}
}
/* Skip over any white space before the integer string */
while (isspace(c))
{
c = obj->get(obj);
}
/* But we only perform the data conversion if we still have
* bytes remaining in the input data stream.
*/
if (c > 0)
{
FAR char *endptr;
int prefix;
bool stopconv;
int errsave;
unsigned long tmplong = 0;
#ifdef CONFIG_LIBC_LONG_LONG
unsigned long long tmplonglong = 0;
#endif
/* Copy the real string into a temporary working buffer. */
if (!width || width > sizeof(tmp) - 1)
{
width = sizeof(tmp) - 1;
}
/* The base of the integer conversion depends on the
* specific conversion specification.
*/
fwidth = 0;
prefix = 0;
stopconv = false;
sign = false;
switch (*fmt)
{
default:
case 'd':
sign = true;
/* FALLTHROUGH */
case 'u':
while (fwidth < width && !stopconv)
{
if (c == '-' || c == '+')
{
if (fwidth != 0)
{
stopconv = true;
}
}
else if (!(c >= '0' && c <= '9'))
{
stopconv = true;
}
if (!stopconv)
{
tmp[fwidth++] = c;
c = obj->get(obj);
}
}
base = 10;
break;
case 'x':
case 'X':
while (fwidth < width && !stopconv)
{
if (c == '-' || c == '+')
{
if (fwidth != 0)
{
stopconv = true;
}
}
else if (c == '0')
{
if (prefix == 0)
{
prefix = 1;
}
}
else if (c == 'x' || c == 'X')
{
if (prefix == 1)
{
prefix = 2;
}
else
{
stopconv = true;
}
}
else if (!((c >= '0' && c <= '9') ||
(c >= 'a' && c <= 'f') ||
(c >= 'A' && c <= 'F')))
{
stopconv = true;
}
else
{
prefix = 2;
}
if (!stopconv)
{
tmp[fwidth++] = c;
c = obj->get(obj);
}
}
base = 16;
break;
case 'o':
while (fwidth < width && !stopconv)
{
if (c == '-' || c == '+')
{
if (fwidth != 0)
{
stopconv = true;
}
}
else if (!(c >= '0' && c <= '7'))
{
stopconv = true;
}
if (!stopconv)
{
tmp[fwidth++] = c;
c = obj->get(obj);
}
}
base = 8;
break;
case 'b': /* not official? */
while (fwidth < width && !stopconv)
{
if (c == '-' || c == '+')
{
if (fwidth != 0)
{
stopconv = true;
}
}
else if (!(c >= '0' && c <= '1'))
{
stopconv = true;
}
if (!stopconv)
{
tmp[fwidth++] = c;
c = obj->get(obj);
}
}
base = 2;
break;
case 'i':
sign = true;
base = 10;
while (fwidth < width && !stopconv)
{
if (c == '-' || c == '+')
{
if (fwidth != 0)
{
stopconv = true;
}
}
else if (c == '0')
{
if (prefix == 0)
{
prefix = 1;
base = 8;
}
}
else if (c == 'x' || c == 'X')
{
if (prefix == 1)
{
prefix = 2;
base = 16;
}
else
{
stopconv = true;
}
}
else if (!((c >= '0' && c <= '7' && base >= 8) ||
(c >= '8' && c <= '9' && base >= 10) ||
(c >= 'a' && c <= 'f' && base == 16) ||
(c >= 'A' && c <= 'F' && base == 16)))
{
stopconv = true;
}
else
{
prefix = 2;
}
if (!stopconv)
{
tmp[fwidth++] = c;
c = obj->get(obj);
}
}
break;
}
tmp[fwidth] = 0;
linfo("tmp[]=\"%s\"\n", tmp);
/* Perform the integer conversion */
/* Preserve the errno value */
errsave = get_errno();
set_errno(0);
switch (modifier)
{
#ifndef CONFIG_LIBC_LONG_LONG
case LL_MOD:
#endif
case HH_MOD:
case H_MOD:
case NO_MOD:
default:
if (sign)
{
tmplong = strtol(tmp, &endptr, base);
}
else
{
tmplong = strtoul(tmp, &endptr, base);
}
break;
#ifdef CONFIG_LIBC_LONG_LONG
case LL_MOD:
if (sign)
{
tmplonglong = strtoll(tmp, &endptr, base);
}
else
{
tmplonglong = strtoull(tmp, &endptr, base);
}
break;
#endif
}
/* Check if the number was successfully converted */
if (tmp == endptr || get_errno() == ERANGE)
{
*lastc = c;
return assigncount;
}
set_errno(errsave);
if (!noassign)
{
/* We have to check whether we need to return a long or
* an int.
*/
switch (modifier)
{
case HH_MOD:
linfo("Return %ld to 0x%p\n", tmplong, pchar);
*pchar = (unsigned char)tmplong;
break;
case H_MOD:
linfo("Return %ld to 0x%p\n", tmplong, pshort);
*pshort = (unsigned short)tmplong;
break;
case NO_MOD:
linfo("Return %ld to 0x%p\n", tmplong, pint);
*pint = (unsigned int)tmplong;
break;
#ifndef CONFIG_LIBC_LONG_LONG
case L_MOD:
#endif
default:
linfo("Return %ld to 0x%p\n", tmplong, plong);
*plong = tmplong;
break;
#ifdef CONFIG_LIBC_LONG_LONG
case LL_MOD:
linfo("Return %lld to 0x%p\n", tmplonglong,
plonglong);
*plonglong = tmplonglong;
break;
#endif
}
assigncount++;
}
count++;
}
}
/* Process %a, %A, %f, %F, %e, %E, %g, and %G: Floating point
* conversions.
*/
else if (strchr("aAfFeEgG", *fmt) != NULL)
{
#ifdef CONFIG_HAVE_DOUBLE
FAR double *pd = NULL;
#endif
FAR float *pf = NULL;
linfo("Performing floating point conversion\n");
/* Get a pointer to the double value. We need to do this even
* if we have reached the end of the input data in order to
* upate the 'ap' variable.
*/
if (!noassign)
{
/* We have to check whether we need to return a float or a
* double.
*/
#ifdef CONFIG_HAVE_DOUBLE
if (modifier >= L_MOD)
{
pd = va_arg(ap, FAR double *);
*pd = 0.0;
}
else
#endif
{
pf = va_arg(ap, FAR float *);
*pf = 0.0;
}
}
#ifdef CONFIG_LIBC_FLOATINGPOINT
/* Skip over any white space before the real string */
while (isspace(c))
{
c = obj->get(obj);
}
/* But we only perform the data conversion is we still have
* bytes remaining in the input data stream.
*/
if (c > 0)
{
FAR char *endptr;
bool expnt;
bool dot;
bool sign;
bool stopconv;
int errsave;
# ifdef CONFIG_HAVE_DOUBLE
double dvalue;
# endif
float fvalue;
/* Was a fieldwidth specified? */
if (!width || width > sizeof(tmp) - 1)
{
width = sizeof(tmp) - 1;
}
/* Copy the real string into a temporary working buffer. */
fwidth = 0;
expnt = false;
sign = false;
dot = false;
stopconv = false;
while (fwidth < width && !stopconv)
{
if (c == '-' || c == '+')
{
if (!sign)
{
sign = true;
}
else
{
stopconv = true;
}
}
else if (c == '.')
{
if (!dot)
{
dot = true;
sign = true;
}
else
{
stopconv = true;
}
}
else if (c == 'e' || c == 'E')
{
if (!expnt)
{
expnt = true;
sign = false;
}
else
{
stopconv = true;
}
}
else if (!(c >= '0' && c <= '9'))
{
stopconv = true;
}
else
{
sign = true;
}
if (!stopconv)
{
tmp[fwidth++] = c;
c = obj->get(obj);
}
}
tmp[fwidth] = 0;
linfo("tmp[]=\"%s\"\n", tmp);
/* Perform the floating point conversion */
/* Preserve the errno value */
errsave = get_errno();
set_errno(0);
# ifdef CONFIG_HAVE_DOUBLE
if (modifier >= L_MOD)
{
/* Get the converted double value */
dvalue = strtod(tmp, &endptr);
}
else
# endif
{
fvalue = strtof(tmp, &endptr);
}
/* Check if the number was successfully converted */
if (tmp == endptr || get_errno() == ERANGE)
{
*lastc = c;
return assigncount;
}
set_errno(errsave);
if (!noassign)
{
/* We have to check whether we need to return a float or
* a double.
*/
# ifdef CONFIG_HAVE_DOUBLE
if (modifier >= L_MOD)
{
/* Return the double value */
linfo("Return %f to %p\n", dvalue, pd);
*pd = dvalue;
}
else
# endif
{
/* Return the float value */
linfo("Return %f to %p\n", (double)fvalue, pf);
*pf = fvalue;
}
assigncount++;
}
count++;
}
#endif
}
/* Process %n: Character count */
else if (*fmt == 'n')
{
linfo("Performing character count\n");
if (!noassign)
{
size_t nchars = (size_t) (obj->nget - ngetstart);
if (c != EOF)
{
/* One more character already read */
nchars--;
}
/* Note %n does not count as a conversion */
switch (modifier)
{
case HH_MOD:
pchar = va_arg(ap, FAR unsigned char *);
*pchar = (unsigned char)nchars;
break;
case H_MOD:
pshort = va_arg(ap, FAR unsigned short *);
*pshort = (unsigned short)nchars;
break;
case NO_MOD:
pint = va_arg(ap, FAR unsigned int *);
*pint = (unsigned int)nchars;
break;
default:
case L_MOD:
plong = va_arg(ap, FAR unsigned long *);
*plong = (unsigned long)nchars;
break;
#ifdef CONFIG_LIBC_LONG_LONG
case LL_MOD:
plonglong = va_arg(ap, FAR unsigned long long *);
*plonglong = (unsigned long long)nchars;
break;
#endif
}
}
count++;
}
else if (*fmt == '%')
{
if (c != '%')
{
break;
}
else
{
c = obj->get(obj);
}
}
width = 0;
noassign = false;
modifier = NO_MOD;
fmt++;
}
/* It is not a conversion specifier */
else if (c > 0)
{
#if 0
/* Skip over any leading spaces in the input buffer */
while (isspace(c))
{
c = obj->get(obj);
}
#endif
/* Skip over matching characters in the buffer and format */
if (*fmt != c)
{
break;
}
else
{
fmt++;
c = obj->get(obj);
}
}
else
{
/* NULL terminator encountered */
break;
}
}
/* sscanf is required to return EOF if the input ends before the first
* matching failure or conversion.
*/
*lastc = c;
return (count || !conv) ? assigncount : EOF;
}