/**************************************************************
 * Original:
 * Patrick Powell Tue Apr 11 09:48:21 PDT 1995
 * A bombproof version of doprnt(dopr) included.
 * Sigh.  This sort of thing is always nasty do deal with.  Note that
 * the version here does not include floating point...
 *
 * snprintf() is used instead of sprintf() as it does limit checks
 * for string length.  This covers a nasty loophole.
 *
 * The other functions are there to prevent NULL pointers from
 * causing nast effects.
 *
 * More Recently:
 *  Brandon Long <blong@fiction.net> 9/15/96 for mutt 0.43
 *  This was ugly.  It is still ugly.  I opted out of floating point
 *  numbers, but the formatter understands just about everything
 *  from the normal C string format, at least as far as I can tell from
 *  the Solaris 2.5 printf(3S) man page.
 *
 *  Brandon Long <blong@fiction.net> 10/22/97 for mutt 0.87.1
 *    Ok, added some minimal floating point support, which means this
 *    probably requires libm on most operating systems.  Don't yet
 *    support the exponent(e,E) and sigfig(g,G).  Also, fmtint()
 *    was pretty badly broken, it just wasn't being exercised in ways
 *    which showed it, so that's been fixed.  Also, formated the code
 *    to mutt conventions, and removed dead code left over from the
 *    original.  Also, there is now a builtin-test, just compile with:
 *           gcc -DTEST_SNPRINTF -o snprintf snprintf.c -lm
 *    and run snprintf for results.
 *
 *  Thomas Roessler <roessler@guug.de> 01/27/98 for mutt 0.89i
 *    The PGP code was using unsigned hexadecimal formats.
 *    Unfortunately, unsigned formats simply didn't work.
 *
 *  Michael Elkins <me@cs.hmc.edu> 03/05/98 for mutt 0.90.8
 *    The original code assumed that both snprintf() and vsnprintf() were
 *    missing.  Some systems only have snprintf() but not vsnprintf(), so
 *    the code is now broken down under HAVE_SNPRINTF and HAVE_VSNPRINTF.
 *
 **************************************************************/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif


#if !defined(HAVE_SNPRINTF) || !defined(HAVE_VSNPRINTF)

#include <string.h>
#include <ctype.h>
#include <sys/types.h>

/* Define this as a fall through, HAVE_STDARG_H is probably already set */

#define HAVE_VARARGS_H

/* varargs declarations: */

#if defined(HAVE_STDARG_H)
#include <stdarg.h>
#define HAVE_STDARGS		/* let's hope that works everywhere(mj) */
#define VA_LOCAL_DECL   va_list ap
#define VA_START(f)     va_start(ap, f)
#define VA_SHIFT(v,t)  ;	/* no-op for ANSI */
#define VA_END          va_end(ap)
#else
#if defined(HAVE_VARARGS_H)
#include <varargs.h>
#undef HAVE_STDARGS
#define VA_LOCAL_DECL   va_list ap
#define VA_START(f)     va_start(ap)	/* f is ignored! */
#define VA_SHIFT(v,t) v = va_arg(ap,t)
#define VA_END        va_end(ap)
#else
/*XX ** NO VARARGS ** XX */
#endif
#endif

/*int snprintf(char *str, size_t count, const char *fmt, ...); */
/*int vsnprintf(char *str, size_t count, const char *fmt, va_list arg); */

static void
dopr(char *buffer, size_t maxlen, const char *format, va_list args);
static void
fmtstr(char *buffer, size_t * currlen, size_t maxlen, char *value,
		int flags, int min, int max);
static void
fmtint(char *buffer, size_t * currlen, size_t maxlen, long value,
		int base, int min, int max, int flags);
static void
fmtfp(char *buffer, size_t * currlen, size_t maxlen, long double fvalue,
		int min, int max, int flags);
static void
dopr_outch(char *buffer, size_t * currlen, size_t maxlen, char c);

/*
 * dopr(): poor man's version of doprintf
 */

/* format read states */
#define DP_S_DEFAULT 0
#define DP_S_FLAGS   1
#define DP_S_MIN     2
#define DP_S_DOT     3
#define DP_S_MAX     4
#define DP_S_MOD     5
#define DP_S_CONV    6
#define DP_S_DONE    7

/* format flags - Bits */
#define DP_F_MINUS 	(1 << 0)
#define DP_F_PLUS  	(1 << 1)
#define DP_F_SPACE 	(1 << 2)
#define DP_F_NUM   	(1 << 3)
#define DP_F_ZERO  	(1 << 4)
#define DP_F_UP    	(1 << 5)
#define DP_F_UNSIGNED 	(1 << 6)

/* Conversion Flags */
#define DP_C_SHORT   1
#define DP_C_LONG    2
#define DP_C_LDOUBLE 3

#define char_to_int(p)(p - '0')
#define MAX(p,q)((p >= q) ? p : q)

static void
dopr(char *buffer, size_t maxlen, const char *format, va_list args)
{
	char ch;
	long value;
	long double fvalue;
	char *strvalue;
	int min;
	int max;
	int state;
	int flags;
	int cflags;
	size_t currlen;

	state = DP_S_DEFAULT;
	currlen = flags = cflags = min = 0;
	max = -1;
	ch = *format++;

	while (state != DP_S_DONE)
	{
		if ((ch == '\0') ||(currlen >= maxlen))
			state = DP_S_DONE;

		switch(state)
		{
			case DP_S_DEFAULT:
				if (ch == '%')
					state = DP_S_FLAGS;
				else
					dopr_outch(buffer, &currlen, maxlen, ch);
				ch = *format++;
				break;
			case DP_S_FLAGS:
				switch(ch)
				{
					case '-':
						flags |= DP_F_MINUS;
						ch = *format++;
						break;
					case '+':
						flags |= DP_F_PLUS;
						ch = *format++;
						break;
					case ' ':
						flags |= DP_F_SPACE;
						ch = *format++;
						break;
					case '#':
						flags |= DP_F_NUM;
						ch = *format++;
						break;
					case '0':
						flags |= DP_F_ZERO;
						ch = *format++;
						break;
					default:
						state = DP_S_MIN;
						break;
				}
				break;
			case DP_S_MIN:
				if (isdigit((unsigned char) ch))
				{
					min = 10 * min + char_to_int(ch);
					ch = *format++;
				}
				else if (ch == '*')
				{
					min = va_arg(args, int);
					ch = *format++;
					state = DP_S_DOT;
				}
				else
					state = DP_S_DOT;
				break;
			case DP_S_DOT:
				if (ch == '.')
				{
					state = DP_S_MAX;
					ch = *format++;
				}
				else
					state = DP_S_MOD;
				break;
			case DP_S_MAX:
				if (isdigit((unsigned char) ch))
				{
					if (max < 0)
						max = 0;
					max = 10 * max + char_to_int(ch);
					ch = *format++;
				}
				else if (ch == '*')
				{
					max = va_arg(args, int);
					ch = *format++;
					state = DP_S_MOD;
				}
				else
					state = DP_S_MOD;
				break;
			case DP_S_MOD:
				/* Currently, we don't support Long Long, bummer */
				switch(ch)
				{
					case 'h':
						cflags = DP_C_SHORT;
						ch = *format++;
						break;
					case 'l':
						cflags = DP_C_LONG;
						ch = *format++;
						break;
					case 'L':
						cflags = DP_C_LDOUBLE;
						ch = *format++;
						break;
					default:
						break;
				}
				state = DP_S_CONV;
				break;
			case DP_S_CONV:
				switch(ch)
				{
					case 'd':
					case 'i':
						if (cflags == DP_C_SHORT)
							value = va_arg(args, short int);
						else if (cflags == DP_C_LONG)
							value = va_arg(args, long int);
						else
							value = va_arg(args, int);
						fmtint(buffer, &currlen, maxlen, value, 10, min, max, flags);
						break;
					case 'o':
						flags |= DP_F_UNSIGNED;
						if (cflags == DP_C_SHORT)
							value = va_arg(args, unsigned short int);
						else if (cflags == DP_C_LONG)
							value = va_arg(args, unsigned long int);
						else
							value = va_arg(args, unsigned int);
						fmtint(buffer, &currlen, maxlen, value, 8, min, max, flags);
						break;
					case 'u':
						flags |= DP_F_UNSIGNED;
						if (cflags == DP_C_SHORT)
							value = va_arg(args, unsigned short int);
						else if (cflags == DP_C_LONG)
							value = va_arg(args, unsigned long int);
						else
							value = va_arg(args, unsigned int);
						fmtint(buffer, &currlen, maxlen, value, 10, min, max, flags);
						break;
					case 'X':
						flags |= DP_F_UP;
					case 'x':
						flags |= DP_F_UNSIGNED;
						if (cflags == DP_C_SHORT)
							value = va_arg(args, unsigned short int);
						else if (cflags == DP_C_LONG)
							value = va_arg(args, unsigned long int);
						else
							value = va_arg(args, unsigned int);
						fmtint(buffer, &currlen, maxlen, value, 16, min, max, flags);
						break;
					case 'f':
						if (cflags == DP_C_LDOUBLE)
							fvalue = va_arg(args, long double);
						else
							fvalue = va_arg(args, double);
						/* um, floating point? */
						fmtfp(buffer, &currlen, maxlen, fvalue, min, max, flags);
						break;
					case 'E':
						flags |= DP_F_UP;
					case 'e':
						if (cflags == DP_C_LDOUBLE)
							fvalue = va_arg(args, long double);
						else
							fvalue = va_arg(args, double);
						break;
					case 'G':
						flags |= DP_F_UP;
					case 'g':
						if (cflags == DP_C_LDOUBLE)
							fvalue = va_arg(args, long double);
						else
							fvalue = va_arg(args, double);
						break;
					case 'c':
						dopr_outch(buffer, &currlen, maxlen, va_arg(args, int));
						break;
					case 's':
						strvalue = va_arg(args, char *);
						if (max < 0)
							max = maxlen;	/* ie, no max */
						fmtstr(buffer, &currlen, maxlen, strvalue, flags, min, max);
						break;
					case 'p':
						strvalue = va_arg(args, void *);
						fmtint(buffer, &currlen, maxlen,(long) strvalue, 16, min, max, flags);
						break;
					case 'n':
						if (cflags == DP_C_SHORT)
						{
							short int *num;
							num = va_arg(args, short int *);
							*num = currlen;
						}
						else if (cflags == DP_C_LONG)
						{
							long int *num;
							num = va_arg(args, long int *);
							*num = currlen;
						}
						else
						{
							int *num;
							num = va_arg(args, int *);
							*num = currlen;
						}
						break;
					case '%':
						dopr_outch(buffer, &currlen, maxlen, ch);
						break;
					case 'w':
						/* not supported yet, treat as next char */
						ch = *format++;
						break;
					default:
						/* Unknown, skip */
						break;
				}
				ch = *format++;
				state = DP_S_DEFAULT;
				flags = cflags = min = 0;
				max = -1;
				break;
			case DP_S_DONE:
				break;
			default:
				/* hmm? */
				break;		/* some picky compilers need this */
		}
	}
	if (currlen < maxlen - 1)
		buffer[currlen] = '\0';
	else
		buffer[maxlen - 1] = '\0';
}

static void
fmtstr(char *buffer, size_t * currlen, size_t maxlen,
		char *value, int flags, int min, int max)
{
	int padlen, strln;		/* amount to pad */
	int cnt = 0;

	if (value == 0)
	{
		value = "<NULL>";
	}

	for (strln = 0; value[strln]; ++strln);	/* strlen */
	padlen = min - strln;
	if (padlen < 0)
		padlen = 0;
	if (flags & DP_F_MINUS)
		padlen = -padlen;		/* Left Justify */

	while ((padlen > 0) &&(cnt < max))
	{
		dopr_outch(buffer, currlen, maxlen, ' ');
		--padlen;
		++cnt;
	}
	while (*value &&(cnt < max))
	{
		dopr_outch(buffer, currlen, maxlen, *value++);
		++cnt;
	}
	while ((padlen < 0) &&(cnt < max))
	{
		dopr_outch(buffer, currlen, maxlen, ' ');
		++padlen;
		++cnt;
	}
}

/* Have to handle DP_F_NUM(ie 0x and 0 alternates) */

	static void
fmtint(char *buffer, size_t * currlen, size_t maxlen,
		long value, int base, int min, int max, int flags)
{
	int signvalue = 0;
	unsigned long uvalue;
	char convert[20];
	int place = 0;
	int spadlen = 0;		/* amount to space pad */
	int zpadlen = 0;		/* amount to zero pad */
	int caps = 0;

	if (max < 0)
		max = 0;

	uvalue = value;

	if (!(flags & DP_F_UNSIGNED))
	{
		if (value < 0)
		{
			signvalue = '-';
			uvalue = -value;
		}
		else if (flags & DP_F_PLUS)	/* Do a sign(+/i) */
			signvalue = '+';
		else if (flags & DP_F_SPACE)
			signvalue = ' ';
	}

	if (flags & DP_F_UP)
		caps = 1;			/* Should characters be upper case? */

	do
	{
		convert[place++] =
			(caps ? "0123456789ABCDEF" : "0123456789abcdef")
			[uvalue %(unsigned) base];
		uvalue =(uvalue /(unsigned) base);
	}
	while (uvalue &&(place < 20));
	if (place == 20)
		place--;
	convert[place] = 0;

	zpadlen = max - place;
	spadlen = min - MAX(max, place) -(signvalue ? 1 : 0);
	if (zpadlen < 0)
		zpadlen = 0;
	if (spadlen < 0)
		spadlen = 0;
	if (flags & DP_F_ZERO)
	{
		zpadlen = MAX(zpadlen, spadlen);
		spadlen = 0;
	}
	if (flags & DP_F_MINUS)
		spadlen = -spadlen;		/* Left Justifty */

#ifdef DEBUG_SNPRINTF
	dprint(1,(debugfile, "zpad: %d, spad: %d, min: %d, max: %d, place: %d\n",
				zpadlen, spadlen, min, max, place));
#endif

	/* Spaces */
	while (spadlen > 0)
	{
		dopr_outch(buffer, currlen, maxlen, ' ');
		--spadlen;
	}

	/* Sign */
	if (signvalue)
		dopr_outch(buffer, currlen, maxlen, signvalue);

	/* Zeros */
	if (zpadlen > 0)
	{
		while (zpadlen > 0)
		{
			dopr_outch(buffer, currlen, maxlen, '0');
			--zpadlen;
		}
	}

	/* Digits */
	while (place > 0)
		dopr_outch(buffer, currlen, maxlen, convert[--place]);

	/* Left Justified spaces */
	while (spadlen < 0)
	{
		dopr_outch(buffer, currlen, maxlen, ' ');
		++spadlen;
	}
}

	static long double
abs_val(long double value)
{
	long double result = value;

	if (value < 0)
		result = -value;

	return result;
}

	static long double
pow10(int exp)
{
	long double result = 1;

	while (exp)
	{
		result *= 10;
		exp--;
	}

	return result;
}

	static long
round(long double value)
{
	long intpart;

	intpart = value;
	value = value - intpart;
	if (value >= 0.5)
		intpart++;

	return intpart;
}

	static void
fmtfp(char *buffer, size_t * currlen, size_t maxlen,
		long double fvalue, int min, int max, int flags)
{
	int signvalue = 0;
	long double ufvalue;
	char iconvert[20];
	char fconvert[20];
	int iplace = 0;
	int fplace = 0;
	int padlen = 0;		/* amount to pad */
	int zpadlen = 0;
	int caps = 0;
	long intpart;
	long fracpart;

	/*
	 * AIX manpage says the default is 0, but Solaris says the default
	 * is 6, and sprintf on AIX defaults to 6
	 */
	if (max < 0)
		max = 6;

	ufvalue = abs_val(fvalue);

	if (fvalue < 0)
		signvalue = '-';
	else if (flags & DP_F_PLUS)	/* Do a sign(+/i) */
		signvalue = '+';
	else if (flags & DP_F_SPACE)
		signvalue = ' ';

#if 0
	if (flags & DP_F_UP)
		caps = 1;			/* Should characters be upper case? */
#endif

	intpart = ufvalue;

	/*
	 * Sorry, we only support 9 digits past the decimal because of our
	 * conversion method
	 */
	if (max > 9)
		max = 9;

	/* We "cheat" by converting the fractional part to integer by
	 * multiplying by a factor of 10
	 */
	fracpart = round((pow10(max)) *(ufvalue - intpart));

	if (fracpart >= pow10(max))
	{
		intpart++;
		fracpart -= pow10(max);
	}

#ifdef DEBUG_SNPRINTF
	dprint(1,(debugfile, "fmtfp: %f =? %d.%d\n", fvalue, intpart, fracpart));
#endif

	/* Convert integer part */
	do
	{
		iconvert[iplace++] =
			(caps ? "0123456789ABCDEF" : "0123456789abcdef")[intpart % 10];
		intpart =(intpart / 10);
	}
	while (intpart &&(iplace < 20));
	if (iplace == 20)
		iplace--;
	iconvert[iplace] = 0;

	/* Convert fractional part */
	do
	{
		fconvert[fplace++] =
			(caps ? "0123456789ABCDEF" : "0123456789abcdef")[fracpart % 10];
		fracpart =(fracpart / 10);
	}
	while (fracpart &&(fplace < 20));
	if (fplace == 20)
		fplace--;
	fconvert[fplace] = 0;

	/* -1 for decimal point, another -1 if we are printing a sign */
	padlen = min - iplace - max - 1 -((signvalue) ? 1 : 0);
	zpadlen = max - fplace;
	if (zpadlen < 0)
		zpadlen = 0;
	if (padlen < 0)
		padlen = 0;
	if (flags & DP_F_MINUS)
		padlen = -padlen;		/* Left Justifty */

	if ((flags & DP_F_ZERO) &&(padlen > 0))
	{
		if (signvalue)
		{
			dopr_outch(buffer, currlen, maxlen, signvalue);
			--padlen;
			signvalue = 0;
		}
		while (padlen > 0)
		{
			dopr_outch(buffer, currlen, maxlen, '0');
			--padlen;
		}
	}
	while (padlen > 0)
	{
		dopr_outch(buffer, currlen, maxlen, ' ');
		--padlen;
	}
	if (signvalue)
		dopr_outch(buffer, currlen, maxlen, signvalue);

	while (iplace > 0)
		dopr_outch(buffer, currlen, maxlen, iconvert[--iplace]);

	/*
	 * Decimal point.  This should probably use locale to find the correct
	 * char to print out.
	 */
	dopr_outch(buffer, currlen, maxlen, '.');

	while (fplace > 0)
		dopr_outch(buffer, currlen, maxlen, fconvert[--fplace]);

	while (zpadlen > 0)
	{
		dopr_outch(buffer, currlen, maxlen, '0');
		--zpadlen;
	}

	while (padlen < 0)
	{
		dopr_outch(buffer, currlen, maxlen, ' ');
		++padlen;
	}
}

	static void
dopr_outch(char *buffer, size_t * currlen, size_t maxlen, char c)
{
	if (*currlen < maxlen)
		buffer[(*currlen)++] = c;
}
#endif /* !defined(HAVE_SNPRINTF) || !defined(HAVE_VSNPRINTF) */

#ifndef HAVE_VSNPRINTF
	int
vsnprintf(char *str, size_t count, const char *fmt, va_list args)
{
	str[0] = 0;
	dopr(str, count, fmt, args);
	return (strlen(str));
}
#endif /* !HAVE_VSNPRINTF */

#ifndef HAVE_SNPRINTF
/* VARARGS3 */
#ifdef HAVE_STDARGS
	int
snprintf(char *str, size_t count, const char *fmt,...)
#else
	int
snprintf(va_alist)
	va_dcl
#endif
{
#ifndef HAVE_STDARGS
	char *str;
	size_t count;
	char *fmt;
#endif
	VA_LOCAL_DECL;

	VA_START(fmt);
	VA_SHIFT(str, char *);
	VA_SHIFT(count, size_t);
	VA_SHIFT(fmt, char *);
	(void) vsnprintf(str, count, fmt, ap);
	VA_END;
	return (strlen(str));
}

#ifdef TEST_SNPRINTF
#ifndef LONG_STRING
#define LONG_STRING 1024
#endif
int
main(void)
{
	char buf1[LONG_STRING];
	char buf2[LONG_STRING];
	char *fp_fmt[] =
	{
		"%-1.5f",
		"%1.5f",
		"%123.9f",
		"%10.5f",
		"% 10.5f",
		"%+22.9f",
		"%+4.9f",
		"%01.3f",
		"%4f",
		"%3.1f",
		"%3.2f",
		NULL
	};
	double fp_nums[] =
	{-1.5, 134.21, 91340.2, 341.1234, 0203.9, 0.96, 0.996,
		0.9996, 1.996, 4.136, 0};
	char *int_fmt[] =
	{
		"%-1.5d",
		"%1.5d",
		"%123.9d",
		"%5.5d",
		"%10.5d",
		"% 10.5d",
		"%+22.33d",
		"%01.3d",
		"%4d",
		NULL
	};
	long int_nums[] =
	{-1, 134, 91340, 341, 0203, 0};
	int x, y;
	int fail = 0;
	int num = 0;

	printf("Testing snprintf format codes against system sprintf...\n");

	for (x = 0; fp_fmt[x] != NULL; x++)
		for (y = 0; fp_nums[y] != 0; y++)
		{
			snprintf(buf1, sizeof(buf1), fp_fmt[x], fp_nums[y]);
			sprintf(buf2, fp_fmt[x], fp_nums[y]);
			if (strcmp(buf1, buf2))
			{
				printf("snprintf doesn't match Format: %s\n\tsnprintf = %s\n\tsprintf  = %s\n",
						fp_fmt[x], buf1, buf2);
				fail++;
			}
			num++;
		}

	for (x = 0; int_fmt[x] != NULL; x++)
		for (y = 0; int_nums[y] != 0; y++)
		{
			snprintf(buf1, sizeof(buf1), int_fmt[x], int_nums[y]);
			sprintf(buf2, int_fmt[x], int_nums[y]);
			if (strcmp(buf1, buf2))
			{
				printf("snprintf doesn't match Format: %s\n\tsnprintf = %s\n\tsprintf  = %s\n",
						int_fmt[x], buf1, buf2);
				fail++;
			}
			num++;
		}
	printf("%d tests failed out of %d.\n", fail, num);
}
#endif /* SNPRINTF_TEST */

#endif /* !HAVE_SNPRINTF */