[thirdparty/bird.git] / lib / printf.c

/*
 *	BIRD Library -- Formatted Output
 *
 *	(c) 1991, 1992 Lars Wirzenius & Linus Torvalds
 *
 *	Hacked up for BIRD by Martin Mares <mj@ucw.cz>
 *	Buffer size limitation implemented by Martin Mares.
 */

#include "nest/bird.h"
#include "string.h"

#include <errno.h>

/* we use this so that we can do without the ctype library */
#define is_digit(c)	((c) >= '0' && (c) <= '9')

static int skip_atoi(const char **s)
{
	int i=0;

	while (is_digit(**s))
		i = i*10 + *((*s)++) - '0';
	return i;
}

#define ZEROPAD	1		/* pad with zero */
#define SIGN	2		/* unsigned/signed long */
#define PLUS	4		/* show plus */
#define SPACE	8		/* space if plus */
#define LEFT	16		/* left justified */
#define SPECIAL	32		/* 0x */
#define LARGE	64		/* use 'ABCDEF' instead of 'abcdef' */

#define do_div(n,base) ({ \
int __res; \
__res = ((unsigned long) n) % (unsigned) base; \
n = ((unsigned long) n) / (unsigned) base; \
__res; })

static char * number(char * str, long num, int base, int size, int precision,
	int type, int remains)
{
	char c,sign,tmp[66];
	const char *digits="0123456789abcdefghijklmnopqrstuvwxyz";
	int i;

	if (size >= 0 && (remains -= size) < 0)
		return NULL;
	if (type & LARGE)
		digits = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
	if (type & LEFT)
		type &= ~ZEROPAD;
	if (base < 2 || base > 36)
		return 0;
	c = (type & ZEROPAD) ? '0' : ' ';
	sign = 0;
	if (type & SIGN) {
		if (num < 0) {
			sign = '-';
			num = -num;
			size--;
		} else if (type & PLUS) {
			sign = '+';
			size--;
		} else if (type & SPACE) {
			sign = ' ';
			size--;
		}
	}
	if (type & SPECIAL) {
		if (base == 16)
			size -= 2;
		else if (base == 8)
			size--;
	}
	i = 0;
	if (num == 0)
		tmp[i++]='0';
	else while (num != 0)
		tmp[i++] = digits[do_div(num,base)];
	if (i > precision)
		precision = i;
	size -= precision;
	if (size < 0 && -size > remains)
		return NULL;
	if (!(type&(ZEROPAD+LEFT)))
		while(size-->0)
			*str++ = ' ';
	if (sign)
		*str++ = sign;
	if (type & SPECIAL) {
		if (base==8)
			*str++ = '0';
		else if (base==16) {
			*str++ = '0';
			*str++ = digits[33];
		}
	}
	if (!(type & LEFT))
		while (size-- > 0)
			*str++ = c;
	while (i < precision--)
		*str++ = '0';
	while (i-- > 0)
		*str++ = tmp[i];
	while (size-- > 0)
		*str++ = ' ';
	return str;
}

/**
 * bvsnprintf - BIRD's vsnprintf()
 * @buf: destination buffer
 * @size: size of the buffer
 * @fmt: format string
 * @args: a list of arguments to be formatted
 *
 * This functions acts like ordinary sprintf() except that it checks
 * available space to avoid buffer overflows and it allows some more
 * format specifiers: |%I| for formatting of IP addresses and |%M| for
 * error messages (uses strerror() to translate @errno code to
 * message text). On the other hand, it doesn't support floating
 * point numbers.
 *
 * Result: number of characters of the output string or -1 if
 * the buffer space was insufficient.
 */
int bvsnprintf(char *buf, int size, const char *fmt, va_list args)
{
	int len;
	unsigned long num;
	int i, base;
	char *str, *start;
	const char *s;

	int flags;		/* flags to number() */

	int field_width;	/* width of output field */
	int precision;		/* min. # of digits for integers; max
				   number of chars for from string */
	int qualifier;		/* 'h', 'l', or 'L' for integer fields */

	for (start=str=buf ; *fmt ; ++fmt, size-=(str-start), start=str) {
		if (*fmt != '%') {
			if (!size)
				return -1;
			*str++ = *fmt;
			continue;
		}
			
		/* process flags */
		flags = 0;
		repeat:
			++fmt;		/* this also skips first '%' */
			switch (*fmt) {
				case '-': flags |= LEFT; goto repeat;
				case '+': flags |= PLUS; goto repeat;
				case ' ': flags |= SPACE; goto repeat;
				case '#': flags |= SPECIAL; goto repeat;
				case '0': flags |= ZEROPAD; goto repeat;
				}
		
		/* get field width */
		field_width = -1;
		if (is_digit(*fmt))
			field_width = skip_atoi(&fmt);
		else if (*fmt == '*') {
			++fmt;
			/* it's the next argument */
			field_width = va_arg(args, int);
			if (field_width < 0) {
				field_width = -field_width;
				flags |= LEFT;
			}
		}

		/* get the precision */
		precision = -1;
		if (*fmt == '.') {
			++fmt;	
			if (is_digit(*fmt))
				precision = skip_atoi(&fmt);
			else if (*fmt == '*') {
				++fmt;
				/* it's the next argument */
				precision = va_arg(args, int);
			}
			if (precision < 0)
				precision = 0;
		}

		/* get the conversion qualifier */
		qualifier = -1;
		if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L') {
			qualifier = *fmt;
			++fmt;
		}

		/* default base */
		base = 10;

		if (field_width > size)
			return -1;
		switch (*fmt) {
		case 'c':
			if (!(flags & LEFT))
				while (--field_width > 0)
					*str++ = ' ';
			*str++ = (unsigned char) va_arg(args, int);
			while (--field_width > 0)
				*str++ = ' ';
			continue;

		case 'm':
			s = strerror(errno);
			goto str;
		case 'M':
			s = strerror(va_arg(args, int));
			goto str;
		case 's':
			s = va_arg(args, char *);
			if (!s)
				s = "<NULL>";

		str:
			len = strlen(s);
			if (precision >= 0 && len > precision)
				len = precision;
			if (len > size)
				return -1;

			if (!(flags & LEFT))
				while (len < field_width--)
					*str++ = ' ';
			for (i = 0; i < len; ++i)
				*str++ = *s++;
			while (len < field_width--)
				*str++ = ' ';
			continue;

		case 'p':
			if (field_width == -1) {
				field_width = 2*sizeof(void *);
				flags |= ZEROPAD;
			}
			str = number(str,
				(unsigned long) va_arg(args, void *), 16,
				field_width, precision, flags, size);
			if (!str)
				return -1;
			continue;


		case 'n':
			if (qualifier == 'l') {
				long * ip = va_arg(args, long *);
				*ip = (str - buf);
			} else {
				int * ip = va_arg(args, int *);
				*ip = (str - buf);
			}
			continue;

		/* IP address */
		case 'I':
			if (size < STD_ADDRESS_P_LENGTH)
				return -1;
			if (flags & SPECIAL)
				str = ip_ntox(va_arg(args, ip_addr), str);
			else {
				len = ip_ntop(va_arg(args, ip_addr), str) - str;
				str += len;
				if (field_width >= 0)
					while (len++ < STD_ADDRESS_P_LENGTH)
						*str++ = ' ';
			}
			continue;

		/* integer number formats - set up the flags and "break" */
		case 'o':
			base = 8;
			break;

		case 'X':
			flags |= LARGE;
		case 'x':
			base = 16;
			break;

		case 'd':
		case 'i':
			flags |= SIGN;
		case 'u':
			break;

		default:
			if (size < 2)
				return -1;
			if (*fmt != '%')
				*str++ = '%';
			if (*fmt)
				*str++ = *fmt;
			else
				--fmt;
			continue;
		}
		if (qualifier == 'l')
			num = va_arg(args, unsigned long);
		else if (qualifier == 'h') {
			num = (unsigned short) va_arg(args, int);
			if (flags & SIGN)
				num = (short) num;
		} else if (flags & SIGN)
			num = va_arg(args, int);
		else
			num = va_arg(args, unsigned int);
		str = number(str, num, base, field_width, precision, flags, size);
		if (!str)
			return -1;
	}
	if (!size)
		return -1;
	*str = '\0';
	return str-buf;
}

/**
 * bvsprintf - BIRD's vsprintf()
 * @buf: buffer
 * @fmt: format string
 * @args: a list of arguments to be formatted
 *
 * This function is equivalent to bvsnprintf() with an infinite
 * buffer size. Please use carefully only when you are absolutely
 * sure the buffer won't overflow.
 */
int bvsprintf(char *buf, const char *fmt, va_list args)
{
  return bvsnprintf(buf, 1000000000, fmt, args);
}

/**
 * bsprintf - BIRD's sprintf()
 * @buf: buffer
 * @fmt: format string
 *
 * This function is equivalent to bvsnprintf() with an infinite
 * buffer size and variable arguments instead of a &va_list.
 * Please use carefully only when you are absolutely
 * sure the buffer won't overflow.
 */
int bsprintf(char * buf, const char *fmt, ...)
{
  va_list args;
  int i;

  va_start(args, fmt);
  i=bvsnprintf(buf, 1000000000, fmt, args);
  va_end(args);
  return i;
}

/**
 * bsnprintf - BIRD's snprintf()
 * @buf: buffer
 * @size: buffer size
 * @fmt: format string
 *
 * This function is equivalent to bsnprintf() with variable arguments instead of a &va_list.
 */
int bsnprintf(char * buf, int size, const char *fmt, ...)
{
  va_list args;
  int i;

  va_start(args, fmt);
  i=bvsnprintf(buf, size, fmt, args);
  va_end(args);
  return i;
}
Commit	Line	Data
ecacdfa4 MM	1	/*
	2	* BIRD Library -- Formatted Output
	3	*
	4	* (c) 1991, 1992 Lars Wirzenius & Linus Torvalds
	5	*
	6	* Hacked up for BIRD by Martin Mares <mj@ucw.cz>
53a416d3	7	* Buffer size limitation implemented by Martin Mares.
ecacdfa4 MM	8	*/
	9
	10	#include "nest/bird.h"
	11	#include "string.h"
	12
d997534f	13	#include <errno.h>
d997534f	14
ecacdfa4 MM	15	/* we use this so that we can do without the ctype library */
	16	#define is_digit(c) ((c) >= '0' && (c) <= '9')
	17
	18	static int skip_atoi(const char **s)
	19	{
	20	int i=0;
	21
	22	while (is_digit(**s))
	23	i = i10 + ((*s)++) - '0';
	24	return i;
	25	}
	26
	27	#define ZEROPAD 1 /* pad with zero */
	28	#define SIGN 2 /* unsigned/signed long */
	29	#define PLUS 4 /* show plus */
	30	#define SPACE 8 /* space if plus */
	31	#define LEFT 16 /* left justified */
	32	#define SPECIAL 32 /* 0x */
	33	#define LARGE 64 /* use 'ABCDEF' instead of 'abcdef' */
	34
	35	#define do_div(n,base) ({ \
	36	int __res; \
	37	__res = ((unsigned long) n) % (unsigned) base; \
	38	n = ((unsigned long) n) / (unsigned) base; \
	39	__res; })
	40
53a416d3 MM	41	static char * number(char * str, long num, int base, int size, int precision,
53a416d3 MM	42	int type, int remains)
ecacdfa4 MM	43	{
	44	char c,sign,tmp[66];
	45	const char *digits="0123456789abcdefghijklmnopqrstuvwxyz";
	46	int i;
	47
53a416d3 MM	48	if (size >= 0 && (remains -= size) < 0)
53a416d3 MM	49	return NULL;
ecacdfa4 MM	50	if (type & LARGE)
	51	digits = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
	52	if (type & LEFT)
	53	type &= ~ZEROPAD;
	54	if (base < 2 \|\| base > 36)
	55	return 0;
	56	c = (type & ZEROPAD) ? '0' : ' ';
	57	sign = 0;
	58	if (type & SIGN) {
	59	if (num < 0) {
	60	sign = '-';
	61	num = -num;
	62	size--;
	63	} else if (type & PLUS) {
	64	sign = '+';
	65	size--;
	66	} else if (type & SPACE) {
	67	sign = ' ';
	68	size--;
	69	}
	70	}
	71	if (type & SPECIAL) {
	72	if (base == 16)
	73	size -= 2;
	74	else if (base == 8)
	75	size--;
	76	}
	77	i = 0;
	78	if (num == 0)
	79	tmp[i++]='0';
	80	else while (num != 0)
	81	tmp[i++] = digits[do_div(num,base)];
	82	if (i > precision)
	83	precision = i;
	84	size -= precision;
53a416d3 MM	85	if (size < 0 && -size > remains)
53a416d3 MM	86	return NULL;
ecacdfa4 MM	87	if (!(type&(ZEROPAD+LEFT)))
	88	while(size-->0)
	89	*str++ = ' ';
	90	if (sign)
	91	*str++ = sign;
	92	if (type & SPECIAL) {
	93	if (base==8)
	94	*str++ = '0';
	95	else if (base==16) {
	96	*str++ = '0';
	97	*str++ = digits[33];
	98	}
	99	}
	100	if (!(type & LEFT))
	101	while (size-- > 0)
	102	*str++ = c;
	103	while (i < precision--)
	104	*str++ = '0';
	105	while (i-- > 0)
	106	*str++ = tmp[i];
	107	while (size-- > 0)
	108	*str++ = ' ';
	109	return str;
	110	}
	111
7722938d MM	112	/**
	113	* bvsnprintf - BIRD's vsnprintf()
	114	* @buf: destination buffer
	115	* @size: size of the buffer
	116	* @fmt: format string
	117	* @args: a list of arguments to be formatted
	118	*
	119	* This functions acts like ordinary sprintf() except that it checks
	120	* available space to avoid buffer overflows and it allows some more
	121	* format specifiers: \|%I\| for formatting of IP addresses and \|%M\| for
	122	* error messages (uses strerror() to translate @errno code to
	123	* message text). On the other hand, it doesn't support floating
	124	* point numbers.
	125	*
	126	* Result: number of characters of the output string or -1 if
	127	* the buffer space was insufficient.
	128	*/
53a416d3	129	int bvsnprintf(char buf, int size, const char fmt, va_list args)
ecacdfa4 MM	130	{
	131	int len;
	132	unsigned long num;
	133	int i, base;
53a416d3	134	char str, start;
ecacdfa4 MM	135	const char *s;
	136
	137	int flags; /* flags to number() */
	138
	139	int field_width; /* width of output field */
	140	int precision; /* min. # of digits for integers; max
	141	number of chars for from string */
	142	int qualifier; /* 'h', 'l', or 'L' for integer fields */
	143
53a416d3	144	for (start=str=buf ; *fmt ; ++fmt, size-=(str-start), start=str) {
ecacdfa4	145	if (*fmt != '%') {
53a416d3 MM	146	if (!size)
53a416d3 MM	147	return -1;
ecacdfa4 MM	148	str++ = fmt;
	149	continue;
	150	}
	151
	152	/* process flags */
	153	flags = 0;
	154	repeat:
	155	++fmt; /* this also skips first '%' */
	156	switch (*fmt) {
	157	case '-': flags \|= LEFT; goto repeat;
	158	case '+': flags \|= PLUS; goto repeat;
	159	case ' ': flags \|= SPACE; goto repeat;
	160	case '#': flags \|= SPECIAL; goto repeat;
	161	case '0': flags \|= ZEROPAD; goto repeat;
	162	}
	163
	164	/* get field width */
	165	field_width = -1;
	166	if (is_digit(*fmt))
	167	field_width = skip_atoi(&fmt);
	168	else if (fmt == '') {
	169	++fmt;
	170	/* it's the next argument */
	171	field_width = va_arg(args, int);
	172	if (field_width < 0) {
	173	field_width = -field_width;
	174	flags \|= LEFT;
	175	}
	176	}
	177
	178	/* get the precision */
	179	precision = -1;
	180	if (*fmt == '.') {
	181	++fmt;
	182	if (is_digit(*fmt))
	183	precision = skip_atoi(&fmt);
	184	else if (fmt == '') {
	185	++fmt;
	186	/* it's the next argument */
	187	precision = va_arg(args, int);
	188	}
	189	if (precision < 0)
	190	precision = 0;
	191	}
	192
	193	/* get the conversion qualifier */
	194	qualifier = -1;
	195	if (fmt == 'h' \|\| fmt == 'l' \|\| *fmt == 'L') {
	196	qualifier = *fmt;
	197	++fmt;
	198	}
	199
	200	/* default base */
	201	base = 10;
	202
53a416d3 MM	203	if (field_width > size)
53a416d3 MM	204	return -1;
ecacdfa4 MM	205	switch (*fmt) {
	206	case 'c':
	207	if (!(flags & LEFT))
	208	while (--field_width > 0)
	209	*str++ = ' ';
	210	*str++ = (unsigned char) va_arg(args, int);
	211	while (--field_width > 0)
	212	*str++ = ' ';
	213	continue;
	214
d997534f MM	215	case 'm':
	216	s = strerror(errno);
	217	goto str;
53943a00 MM	218	case 'M':
	219	s = strerror(va_arg(args, int));
	220	goto str;
ecacdfa4 MM	221	case 's':
	222	s = va_arg(args, char *);
	223	if (!s)
	224	s = "<NULL>";
	225
d997534f	226	str:
ecacdfa4 MM	227	len = strlen(s);
	228	if (precision >= 0 && len > precision)
	229	len = precision;
53a416d3 MM	230	if (len > size)
53a416d3 MM	231	return -1;
ecacdfa4 MM	232
	233	if (!(flags & LEFT))
	234	while (len < field_width--)
	235	*str++ = ' ';
	236	for (i = 0; i < len; ++i)
	237	str++ = s++;
	238	while (len < field_width--)
	239	*str++ = ' ';
	240	continue;
	241
	242	case 'p':
	243	if (field_width == -1) {
	244	field_width = 2sizeof(void );
	245	flags \|= ZEROPAD;
	246	}
	247	str = number(str,
	248	(unsigned long) va_arg(args, void *), 16,
53a416d3 MM	249	field_width, precision, flags, size);
	250	if (!str)
	251	return -1;
ecacdfa4 MM	252	continue;
	253
	254
	255	case 'n':
	256	if (qualifier == 'l') {
	257	long * ip = va_arg(args, long *);
	258	*ip = (str - buf);
	259	} else {
	260	int * ip = va_arg(args, int *);
	261	*ip = (str - buf);
	262	}
	263	continue;
	264
	265	/* IP address */
	266	case 'I':
53a416d3 MM	267	if (size < STD_ADDRESS_P_LENGTH)
53a416d3 MM	268	return -1;
ecacdfa4 MM	269	if (flags & SPECIAL)
	270	str = ip_ntox(va_arg(args, ip_addr), str);
	271	else {
	272	len = ip_ntop(va_arg(args, ip_addr), str) - str;
	273	str += len;
	274	if (field_width >= 0)
	275	while (len++ < STD_ADDRESS_P_LENGTH)
	276	*str++ = ' ';
	277	}
	278	continue;
	279
	280	/* integer number formats - set up the flags and "break" */
	281	case 'o':
	282	base = 8;
	283	break;
	284
	285	case 'X':
	286	flags \|= LARGE;
	287	case 'x':
	288	base = 16;
	289	break;
	290
	291	case 'd':
	292	case 'i':
	293	flags \|= SIGN;
	294	case 'u':
	295	break;
	296
	297	default:
53a416d3 MM	298	if (size < 2)
53a416d3 MM	299	return -1;
ecacdfa4 MM	300	if (*fmt != '%')
	301	*str++ = '%';
	302	if (*fmt)
	303	str++ = fmt;
	304	else
	305	--fmt;
	306	continue;
	307	}
	308	if (qualifier == 'l')
	309	num = va_arg(args, unsigned long);
	310	else if (qualifier == 'h') {
4254dc45	311	num = (unsigned short) va_arg(args, int);
ecacdfa4	312	if (flags & SIGN)
4254dc45	313	num = (short) num;
ecacdfa4 MM	314	} else if (flags & SIGN)
	315	num = va_arg(args, int);
	316	else
	317	num = va_arg(args, unsigned int);
53a416d3 MM	318	str = number(str, num, base, field_width, precision, flags, size);
	319	if (!str)
	320	return -1;
ecacdfa4	321	}
53a416d3 MM	322	if (!size)
53a416d3 MM	323	return -1;
ecacdfa4 MM	324	*str = '\0';
	325	return str-buf;
	326	}
	327
7722938d MM	328	/**
	329	* bvsprintf - BIRD's vsprintf()
	330	* @buf: buffer
	331	* @fmt: format string
	332	* @args: a list of arguments to be formatted
	333	*
	334	* This function is equivalent to bvsnprintf() with an infinite
	335	* buffer size. Please use carefully only when you are absolutely
	336	* sure the buffer won't overflow.
	337	*/
53a416d3 MM	338	int bvsprintf(char buf, const char fmt, va_list args)
	339	{
	340	return bvsnprintf(buf, 1000000000, fmt, args);
	341	}
	342
7722938d MM	343	/**
	344	* bsprintf - BIRD's sprintf()
	345	* @buf: buffer
	346	* @fmt: format string
	347	*
	348	* This function is equivalent to bvsnprintf() with an infinite
	349	* buffer size and variable arguments instead of a &va_list.
	350	* Please use carefully only when you are absolutely
	351	* sure the buffer won't overflow.
	352	*/
ecacdfa4 MM	353	int bsprintf(char * buf, const char *fmt, ...)
ecacdfa4 MM	354	{
53a416d3 MM	355	va_list args;
53a416d3 MM	356	int i;
ecacdfa4	357
53a416d3 MM	358	va_start(args, fmt);
	359	i=bvsnprintf(buf, 1000000000, fmt, args);
	360	va_end(args);
	361	return i;
	362	}
	363
7722938d MM	364	/**
	365	* bsnprintf - BIRD's snprintf()
	366	* @buf: buffer
	367	* @size: buffer size
	368	* @fmt: format string
	369	*
	370	* This function is equivalent to bsnprintf() with variable arguments instead of a &va_list.
	371	*/
53a416d3 MM	372	int bsnprintf(char * buf, int size, const char *fmt, ...)
	373	{
	374	va_list args;
	375	int i;
	376
	377	va_start(args, fmt);
	378	i=bvsnprintf(buf, size, fmt, args);
	379	va_end(args);
	380	return i;
ecacdfa4	381	}