/************************************************************
* lib_sscanf.c
*
* Copyright (C) 2007 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* 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 Gregory Nutt 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 <sys/types.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <debug.h>
/************************************************************
* Definitions
************************************************************/
#define MAXLN 128
/************************************************************
* Private Type Declarations
************************************************************/
/************************************************************
* Private Function Prototypes
************************************************************/
/************************************************************
* Global Function Prototypes
************************************************************/
int vsscanf(char *buf, const char *s, va_list ap);
/**********************************************************
* Global Constant Data
**********************************************************/
/************************************************************
* Global Variables
************************************************************/
/**********************************************************
* Private Constant Data
**********************************************************/
static const char spaces[] = " \t\n\r\f\v";
/************************************************************
* Private Variables
************************************************************/
/************************************************************
* Function: sscanf
*
* Description:
* ANSI standard sscanf implementation.
*
************************************************************/
int sscanf(const char *buf, const char *fmt, ...)
{
va_list ap;
int count;
va_start(ap, fmt);
count = vsscanf((char*)buf, fmt, ap);
va_end(ap);
return count;
} /* end sscanf */
/************************************************************
* Function: vsscanf
*
* Description:
* ANSI standard vsscanf implementation.
*
************************************************************/
int vsscanf(char *buf, const char *s, va_list ap)
{
int count;
int noassign;
int width;
int base = 10;
int lflag;
char *tv;
const char *tc;
char tmp[MAXLN];
vdbg("vsscanf: buf=\"%s\" fmt=\"%s\"\n", buf, s);
count = noassign = width = lflag = 0;
while (*s && *buf)
{
/* Skip over white space */
while (isspace(*s))
s++;
/* Check for a conversion specifier */
if (*s == '%')
{
vdbg("vsscanf: Specifier found\n");
/* Check for qualifiers on the conversion specifier */
s++;
for (; *s; s++)
{
vdbg("vsscanf: Processing %c\n", *s);
if (strchr("dibouxcsefg%", *s))
break;
if (*s == '*')
noassign = 1;
else if (*s == 'l' || *s == 'L')
lflag = 1;
else if (*s >= '1' && *s <= '9') {
for (tc = s; isdigit(*s); s++);
strncpy(tmp, tc, s - tc);
tmp[s - tc] = '\0';
width = atoi(tmp);
/* atob(&width, tmp, 10); */
s--;
}
}
/* Process %s: String conversion */
if (*s == 's')
{
vdbg("vsscanf: Performing string conversion\n");
while (isspace(*buf))
buf++;
if (!width)
{
width = strcspn(buf, spaces);
}
if (!noassign)
{
tv = va_arg(ap, char*);
strncpy(tv, buf, width);
tv[width] = '\0';
}
buf += width;
}
/* Process %c: Character conversion */
else if (*s == 'c')
{
vdbg("vsscanf: Performing character conversion\n");
if (!width)
width = 1;
if (!noassign)
{
tv = va_arg(ap, char*);
strncpy(tv, buf, width);
tv[width] = '\0';
}
buf += width;
}
/* Process %d, %o, %b, %x, %u: Various integer conversions */
else if (strchr("dobxu", *s))
{
vdbg("vsscanf: Performing integer conversion\n");
/* Skip over any white space before the integer string */
while (isspace(*buf))
buf++;
/* The base of the integer conversion depends on the specific
* conversion specification.
*/
if (*s == 'd' || *s == 'u')
base = 10;
else if (*s == 'x')
base = 16;
else if (*s == 'o')
base = 8;
else if (*s == 'b')
base = 2;
/* Copy the integer string into a temporary working buffer. */
if (!width)
{
if (isspace(*(s + 1)) || *(s + 1) == 0)
{
width = strcspn(buf, spaces);
}
else
{
width = strchr(buf, *(s + 1)) - buf;
}
}
strncpy(tmp, buf, width);
tmp[width] = '\0';
vdbg("vsscanf: tmp[]=\"%s\"\n", tmp);
/* Perform the integer conversion */
buf += width;
if (!noassign)
{
int *pint = va_arg(ap, int*);
int tmpint = strtol(tmp, NULL, base);
vdbg("vsscanf: Return %d to 0x%p\n", tmpint, pint);
*pint = tmpint;
}
}
/* Process %f: Floating point conversion */
else if (*s == 'f')
{
vdbg("vsscanf: Performing floating point conversion\n");
/* Skip over any white space before the real string */
while (isspace(*buf))
buf++;
/* Copy the real string into a temporary working buffer. */
if (!width)
{
if (isspace(*(s + 1)) || *(s + 1) == 0)
{
width = strcspn(buf, spaces);
}
else
{
width = strchr(buf, *(s + 1)) - buf;
}
}
strncpy(tmp, buf, width);
tmp[width] = '\0';
buf += width;
vdbg("vsscanf: tmp[]=\"%s\"\n", tmp);
/* Perform the floating point conversion */
if (!noassign)
{
/* strtod always returns a double */
double dvalue = strtod(tmp, NULL);
void *pv = va_arg(ap, void*);
vdbg("vsscanf: Return %f to 0x%p\n", dvalue, pv);
/* But we have to check whether we need to return a
* float or a double.
*/
if (lflag)
{
*((double*)pv) = dvalue;
}
else
{
*((float*)pv) = (float)dvalue;
}
}
}
if (!noassign)
count++;
width = noassign = lflag = 0;
s++;
}
/* Its is not a conversion specifier */
else
{
while (isspace(*buf))
buf++;
if (*s != *buf)
break;
else
s++, buf++;
}
}
return count;
}
