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/*
* Scanf code. Extend File namespace with reading code
*/
extend namespace File {
public int fscanf (file f, string format, *poly args ...)
/*
* According to 'format', read from 'f' to 'args'
*/
{
/* Skip whitespace */
void whitespace ()
{
int c;
while (!end (f))
if (!Ctype::isspace (c = getc (f))) {
ungetc (c, f);
break;
}
}
bool isbinary (int c)
{
if ('0' <= c && c <= '1')
return true;
if (c == '-')
return true;
return false;
}
bool isoctal (int c)
{
if ('0' <= c && c <= '7')
return true;
if (c == '-')
return true;
return false;
}
bool isdecimal (int c)
{
if ('0' <= c && c <= '9')
return true;
if (c == '-')
return true;
return false;
}
bool ishex (int c)
{
if ('0' <= c && c <= '9')
return true;
if ('a' <= c && c <= 'f')
return true;
if ('A' <= c && c <= 'F')
return true;
if (c == '-')
return true;
return false;
}
bool isfloat (int c)
{
if ('0' <= c && c <= '9')
return true;
if (c == 'e')
return true;
if (c == '-')
return true;
if (c == '.')
return true;
if (c == '{' || c == '}')
return true;
return false;
}
/* return next integer in input */
int integer (bool(int c) test, int base)
{
int c;
string s = "";
whitespace();
while (!end (f)) {
if (!test (c = getc (f))) {
ungetc (c, f);
break;
}
s = s + String::new(c);
}
return string_to_integer (s, base);
}
/* return next number in input */
real number (bool(int c) test)
{
int c;
string s = "";
whitespace();
while (!end (f)) {
if (!test (c = getc (f))) {
ungetc (c, f);
break;
}
s = s + String::new(c);
}
return string_to_real (s);
}
string word ()
{
whitespace();
string s = "";
while (!end (f)) {
int c = getc(f);
if (!Ctype::isgraph (c)) {
ungetc (c, f);
break;
}
s = s + String::new(c);
}
return s;
}
int i = 0;
int argc = 0;
int c;
while (i < String::length (format) && !end(f) && !error(f))
{
switch (format[i]) {
case ' ':
case '\t':
whitespace ();
break;
case '%':
i++;
switch (format[i]) {
case 'b': case 'B':
*args[argc++] = integer (isbinary, 2);
break;
case 'o': case 'O':
*args[argc++] = integer (isoctal, 8);
break;
case 'd': case 'D':
*args[argc++] = integer (isdecimal, 10);
break;
case 'x': case 'X':
*args[argc++] = integer (ishex, 16);
break;
case 'e': case 'E':
case 'f': case 'F':
case 'g': case 'G':
*args[argc++] = number(isfloat);
break;
case 'c':
*args[argc++] = getc(f);
break;
case 's':
*args[argc++] = word();
break;
default:
if (end (f))
return argc;
c = getc(f);
if (c != format[i]) {
ungetc (c, f);
return argc;
}
break;
}
break;
default:
if (end (f))
return argc;
c = getc(f);
if (c != format[i]) {
ungetc (c, f);
return argc;
}
break;
}
i++;
}
return argc;
}
public int sscanf (string s, string format, *poly args...)
/*
* According to 'format', read from 's' to 'args'
*/
{
file sf = string_read(s);
int n = fscanf (sf, format, args ...);
close(sf);
return n;
}
public namespace ScanfGlobals {
public int scanf (string format, *poly args...)
/*
* According to 'format', read from stdin to 'args'
*/
{
return fscanf (stdin, format, args ...);
}
}
public import ScanfGlobals;
}
import File::ScanfGlobals;
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