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/*
* Copyright (c) 2000-2002 Opsycon AB (www.opsycon.se)
*
* 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 Opsycon AB.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*
*/
#include <ctype.h>
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
static const char* determine_base(const char* p, int& base)
{
if (p[0] == '0') {
switch (p[1]) {
case 'x':
base = 16;
break;
case 't':
case 'n':
base = 10;
break;
case 'o':
base = 8;
break;
default:
base = 10;
return p;
}
return p + 2;
}
base = 10;
return p;
}
static int _atob(unsigned long* vp, const char* p, int base)
{
unsigned long value, v1, v2;
char *q, tmp[20];
int digit;
if (p[0] == '0' && (p[1] == 'x' || p[1] == 'X')) {
base = 16;
p += 2;
}
if (base == 16 && (q = strchr(p, '.')) != 0) {
if (q - p > (int)sizeof(tmp) - 1)
return 0;
strncpy(tmp, p, q - p);
tmp[q - p] = '\0';
if (!_atob(&v1, tmp, 16))
return 0;
++q;
if (strchr(q, '.'))
return 0;
if (!_atob(&v2, q, 16))
return 0;
*vp = (v1 << 16) + v2;
return 1;
}
value = *vp = 0;
for (; *p; p++) {
if (*p >= '0' && *p <= '9')
digit = *p - '0';
else if (*p >= 'a' && *p <= 'f')
digit = *p - 'a' + 10;
else if (*p >= 'A' && *p <= 'F')
digit = *p - 'A' + 10;
else
return 0;
if (digit >= base)
return 0;
value *= base;
value += digit;
}
*vp = value;
return 1;
}
int atob(unsigned int* vp, const char* p, int base)
{
unsigned long v;
if (base == 0)
p = determine_base(p, base);
if (_atob(&v, p, base)) {
*vp = v;
return 1;
}
return 0;
}
#define ISSPACE " \t\n\r\f\v"
int vsscanf(const char* buf, const char* s, va_list ap)
{
int base = 10;
char* t;
char tmp[BUFSIZ];
bool noassign = false;
int count = 0;
int width = 0;
while (*s && *buf) {
while (isspace(*s))
s++;
if (*s == '%') {
s++;
for (; *s; s++) {
if (strchr("dibouxcsefg%", *s))
break;
if (*s == '*')
noassign = true;
else if (*s >= '1' && *s <= '9') {
const char* tc;
for (tc = s; isdigit(*s); s++)
;
strncpy(tmp, tc, s - tc);
tmp[s - tc] = '\0';
atob((uint32_t*)&width, tmp, 10);
s--;
}
}
if (*s == 's') {
while (isspace(*buf))
buf++;
if (!width)
width = strcspn(buf, ISSPACE);
if (!noassign) {
strncpy(t = va_arg(ap, char*), buf, width);
t[width] = '\0';
}
buf += width;
} else if (*s == 'c') {
if (!width)
width = 1;
if (!noassign) {
strncpy(t = va_arg(ap, char*), buf, width);
t[width] = '\0';
}
buf += width;
} else if (strchr("dobxu", *s)) {
while (isspace(*buf))
buf++;
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;
if (!width) {
if (isspace(*(s + 1)) || *(s + 1) == 0) {
width = strcspn(buf, ISSPACE);
} else {
auto* p = strchr(buf, *(s + 1));
if (p)
width = p - buf;
else {
noassign = true;
width = 0;
}
}
}
strncpy(tmp, buf, width);
tmp[width] = '\0';
buf += width;
if (!noassign) {
if (!atob(va_arg(ap, uint32_t*), tmp, base))
noassign = true;
}
}
if (!noassign)
++count;
width = 0;
noassign = false;
++s;
} else {
while (isspace(*buf))
buf++;
if (*s != *buf)
break;
else {
++s;
++buf;
}
}
}
return count;
}
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