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Distributed under the MIT License.
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/************************************************************************ 
 * This file is part of PDCurses. PDCurses is public domain software;	*
 * you may use it for any purpose. This software is provided AS IS with	*
 * NO WARRANTY whatsoever.						*
 *									*
 * If you use PDCurses in an application, an acknowledgement would be	*
 * appreciated, but is not mandatory. If you make corrections or	*
 * enhancements to PDCurses, please forward them to the current		*
 * maintainer for the benefit of other users.				*
 *									*
 * See the file maintain.er for details of the current maintainer.	*
 ************************************************************************/

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <curspriv.h>

RCSID("$Id: scanw.c,v 1.38 2007/06/14 14:11:30 wmcbrine Exp $")

/*man-start**************************************************************

  Name:								scanw

  Synopsis:
	int scanw(const char *fmt, ...);
	int wscanw(WINDOW *win, const char *fmt, ...);
	int mvscanw(int y, int x, const char *fmt, ...);
	int mvwscanw(WINDOW *win, int y, int x, const char *fmt, ...);
	int vwscanw(WINDOW *win, const char *fmt, va_list varglist);
	int vw_scanw(WINDOW *win, const char *fmt, va_list varglist);

  Description:
	These routines correspond to scanf(). scanw() reads input from
	the default window; wscanw() from the specified window.
	mvscanw() and mvwscanw() move the cursor to the specified
	position before reading.

	wgetstr() is called to get a string from the window, and the 
	resulting line is used as input for the scan.  All character 
	interpretation is carried out according to the scanf() function 
	rules.

  Return Value:
	Upon successful completion, the scanw, mvscanw, mvwscanw and
	wscanw functions return the number of items successfully
	matched.  On end-of-file, they return EOF.  Otherwise they
	return ERR.

  Portability				     X/Open    BSD    SYS V
	scanw					Y	Y	Y
	wscanw					Y	Y	Y
	mvscanw					Y	Y	Y
	mvwscanw				Y	Y	Y
	vwscanw					Y	-      4.0
	vw_scanw				Y

**man-end****************************************************************/

#include <string.h>

#ifndef HAVE_VSSCANF
# include <stdlib.h>
# include <ctype.h>
# include <limits.h>

static int _pdc_vsscanf(const char *, const char *, va_list);

# define vsscanf _pdc_vsscanf
#endif

int vwscanw(WINDOW *win, const char *fmt, va_list varglist)
{
	char scanbuf[256];

	PDC_LOG(("vwscanw() - called\n"));

	if (wgetnstr(win, scanbuf, 255) == ERR)
		return ERR;

	return vsscanf(scanbuf, fmt, varglist);
}

int scanw(const char *fmt, ...)
{
	va_list args;
	int retval;

	PDC_LOG(("scanw() - called\n"));

	va_start(args, fmt);
	retval = vwscanw(stdscr, fmt, args);
	va_end(args);

	return retval;
}

int wscanw(WINDOW *win, const char *fmt, ...)
{
	va_list args;
	int retval;

	PDC_LOG(("wscanw() - called\n"));

	va_start(args, fmt);
	retval = vwscanw(win, fmt, args);
	va_end(args);

	return retval;
}

int mvscanw(int y, int x, const char *fmt, ...)
{
	va_list args;
	int retval;

	PDC_LOG(("mvscanw() - called\n"));

	if (move(y, x) == ERR)
		return ERR;

	va_start(args, fmt);
	retval = vwscanw(stdscr, fmt, args);
	va_end(args);

	return retval;
}

int mvwscanw(WINDOW *win, int y, int x, const char *fmt, ...)
{
	va_list args;
	int retval;

	PDC_LOG(("mvscanw() - called\n"));

	if (wmove(win, y, x) == ERR)
		return ERR;

	va_start(args, fmt);
	retval = vwscanw(win, fmt, args);
	va_end(args);

	return retval;
}

int vw_scanw(WINDOW *win, const char *fmt, va_list varglist)
{
	PDC_LOG(("vw_scanw() - called\n"));

	return vwscanw(win, fmt, varglist);
}

#ifndef HAVE_VSSCANF

/* _pdc_vsscanf() - Internal routine to parse and format an input 
   buffer. It scans a series of input fields; each field is formatted 
   according to a supplied format string and the formatted input is 
   stored in the variable number of addresses passed. Returns the number 
   of input fields or EOF on error.

   Don't compile this unless required. Some compilers (at least Borland 
   C++ 3.0) have to link with math libraries due to the use of floats.

   Based on vsscanf.c and input.c from emx 0.8f library source, 
   Copyright (c) 1990-1992 by Eberhard Mattes, who has kindly agreed to 
   its inclusion in PDCurses. */

#define WHITE(x) ((x) == ' ' || (x) == '\t' || (x) == '\n')

#define NEXT(x) \
        do { \
            x = *buf++; \
            if (!x) \
               return (count ? count : EOF); \
            ++chars; \
           } while (0)

#define UNGETC() \
        do { \
            --buf; --chars; \
           } while (0)

static int _pdc_vsscanf(const char *buf, const char *fmt, va_list arg_ptr)
{
	int count, chars, c, width, radix, d, i;
	int *int_ptr;
	long *long_ptr;
	short *short_ptr;
	char *char_ptr;
	unsigned char f;
	char neg, assign, ok, size;
	long n;
	char map[256], end;
	double dx, dd, *dbl_ptr;
	float *flt_ptr;
	int exp;
	char eneg;

	count = 0;
	chars = 0;
	c = 0;
	while ((f = *fmt) != 0)
	{
		if (WHITE(f))
		{
			do
			{
				++fmt;
				f = *fmt;
			}
			while (WHITE(f));
			do
			{
				c = *buf++;
				if (!c)
				{
					if (!f || count)
						return count;
					else
						return EOF;
				} else
					++chars;
			}
			while (WHITE(c));
			UNGETC();
		} else if (f != '%')
		{
			NEXT(c);
			if (c != f)
				return count;
			++fmt;
		} else
		{
			assign = TRUE;
			width = INT_MAX;
			char_ptr = NULL;
			++fmt;
			if (*fmt == '*')
			{
				assign = FALSE;
				++fmt;
			}
			if (isdigit(*fmt))
			{
				width = 0;
				while (isdigit(*fmt))
					width = width * 10 + (*fmt++ - '0');
				if (!width)
					width = INT_MAX;
			}
			size = 0;
			if (*fmt == 'h' || *fmt == 'l')
				size = *fmt++;
			f = *fmt;
			switch (f)
			{
			case 'c':
				if (width == INT_MAX)
					width = 1;
				if (assign)
					char_ptr = va_arg(arg_ptr, char *);
				while (width > 0)
				{
					--width;
					NEXT(c);
					if (assign)
					{
						*char_ptr++ = (char) c;
						++count;
					}
				}
				break;
			case '[':
				memset(map, 0, 256);
				end = 0;
				++fmt;
				if (*fmt == '^')
				{
					++fmt;
					end = 1;
				}
				i = 0;
				for (;;)
				{
					f = (unsigned char) *fmt;
					switch (f)
					{
					case 0:
						/* avoid skipping past 0 */
						--fmt;
						NEXT(c);
						goto string;
					case ']':
						if (i > 0)
						{
							NEXT(c);
							goto string;
						}
						/* no break */
					default:
						if (fmt[1] == '-' && fmt[2]
						    && f <
						    (unsigned char) fmt[2])
						{
							memset(map + f, 1,
							       (unsigned char)
							       fmt[2] - f);
							fmt += 2;
						} else
							map[f] = 1;
						break;
					}
					++fmt;
					++i;
				}
			case 's':
				memset(map, 0, 256);
				map[' '] = 1;
				map['\n'] = 1;
				map['\r'] = 1;
				map['\t'] = 1;
				end = 1;
				do
				{
					NEXT(c);
				}
				while (WHITE(c));
			      string:
				if (assign)
					char_ptr = va_arg(arg_ptr, char *);
				while (width > 0
				       && map[(unsigned char) c] != end)
				{
					--width;
					if (assign)
						*char_ptr++ = (char) c;
					c = *buf++;
					if (!c)
						break;
					else
						++chars;
				}
				if (assign)
				{
					*char_ptr = 0;
					++count;
				}
				if (!c)
					return count;
				else
					UNGETC();
				break;
			case 'f':
			case 'e':
			case 'E':
			case 'g':
			case 'G':
				neg = ok = FALSE;
				dx = 0.0;
				do
				{
					NEXT(c);
				}
				while (WHITE(c));
				if (c == '+')
				{
					NEXT(c);
					--width;
				} else if (c == '-')
				{
					neg = TRUE;
					NEXT(c);
					--width;
				}
				while (width > 0 && isdigit(c))
				{
					--width;
					dx = dx * 10.0 + (double) (c - '0');
					ok = TRUE;
					c = *buf++;
					if (!c)
						break;
					else
						++chars;
				}
				if (width > 0 && c == '.')
				{
					--width;
					dd = 10.0;
					NEXT(c);
					while (width > 0 && isdigit(c))
					{
						--width;
						dx += (double) (c - '0') / dd;
						dd *= 10.0;
						ok = TRUE;
						c = *buf++;
						if (!c)
							break;
						else
							++chars;
					}
				}
				if (!ok)
					return count;
				if (width > 0 && (c == 'e' || c == 'E'))
				{
					eneg = FALSE;
					exp = 0;
					NEXT(c);
					--width;
					if (width > 0 && c == '+')
					{
						NEXT(c);
						--width;
					} else if (width > 0 && c == '-')
					{
						eneg = TRUE;
						NEXT(c);
						--width;
					}
					if (!(width > 0 && isdigit(c)))
					{
						UNGETC();
						return count;
					}
					while (width > 0 && isdigit(c))
					{
						--width;
						exp = exp * 10 + (c - '0');
						c = *buf++;
						if (!c)
							break;
						else
							++chars;
					}
					if (eneg)
						exp = -exp;
					while (exp > 0)
					{
						dx *= 10.0;
						--exp;
					}
					while (exp < 0)
					{
						dx /= 10.0;
						++exp;
					}
				}
				if (assign)
				{
					if (neg)
						dx = -dx;
					if (size == 'l')
					{
						dbl_ptr =
						    va_arg(arg_ptr, double *);
						*dbl_ptr = dx;
					} else
					{
						flt_ptr =
						    va_arg(arg_ptr, float *);
						*flt_ptr = (float) dx;
					}
					++count;
				}
				if (!c)
					return count;
				else
					UNGETC();
				break;
			case 'i':
				neg = FALSE;
				radix = 10;
				do
				{
					NEXT(c);
				}
				while (WHITE(c));
				if (!(width > 0 && c == '0'))
					goto scan_complete_number;
				NEXT(c);
				--width;
				if (width > 0 && (c == 'x' || c == 'X'))
				{
					NEXT(c);
					radix = 16;
					--width;
				} else if (width > 0 && (c >= '0' && c <= '7'))
					radix = 8;
				goto scan_unsigned_number;
			case 'd':
			case 'u':
			case 'o':
			case 'x':
			case 'X':
				do
				{
					NEXT(c);
				}
				while (WHITE(c));
				switch (f)
				{
				case 'o':
					radix = 8;
					break;
				case 'x':
				case 'X':
					radix = 16;
					break;
				default:
					radix = 10;
					break;
				}
			      scan_complete_number:
				neg = FALSE;
				if (width > 0 && c == '+')
				{
					NEXT(c);
					--width;
				} else if (width > 0 && c == '-' && radix == 10)
				{
					neg = TRUE;
					NEXT(c);
					--width;
				}
			      scan_unsigned_number:
				n = 0;
				ok = FALSE;
				while (width > 0)
				{
					--width;
					if (isdigit(c))
						d = c - '0';
					else if (isupper(c))
						d = c - 'A' + 10;
					else if (islower(c))
						d = c - 'a' + 10;
					else
						break;
					if (d < 0 || d >= radix)
						break;
					ok = TRUE;
					n = n * radix + d;
					c = *buf++;
					if (!c)
						break;
					else
						++chars;
				}
				if (!ok)
					return count;
				if (assign)
				{
					if (neg)
						n = -n;
					switch (size)
					{
					case 'h':
						short_ptr =
						    va_arg(arg_ptr, short *);
						*short_ptr = (short) n;
						break;
					case 'l':
						long_ptr =
						    va_arg(arg_ptr, long *);
						*long_ptr = (long) n;
						break;
					default:
						int_ptr =
						    va_arg(arg_ptr, int *);
						*int_ptr = (int) n;
					}
					++count;
				}
				if (!c)
					return count;
				else
					UNGETC();
				break;
			case 'n':
				if (assign)
				{
					int_ptr = va_arg(arg_ptr, int *);
					*int_ptr = chars;
					++count;
				}
				break;
			default:
				if (!f)	/* % at end of string */
					return count;
				NEXT(c);
				if (c != f)
					return count;
				break;
			}
			++fmt;
		}
	}
	return count;
}
#endif /* HAVE_VSSCANF */

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