[unix-history] / usr / src / usr.bin / ex / printf.c

/*
 * Copyright (c) 1980 Regents of the University of California.
 * All rights reserved.  The Berkeley software License Agreement
 * specifies the terms and conditions for redistribution.
 */

#ifndef lint
static char *sccsid = "@(#)printf.c	7.4 (Berkeley) %G%";
/* The pwb version this is based on */
static char *printf_id = "@(#) printf.c:2.2 6/5/79";
#endif not lint

#include <varargs.h>
 
/*
 * This version of printf is compatible with the Version 7 C
 * printf. The differences are only minor except that this
 * printf assumes it is to print through putchar. Version 7
 * printf is more general (and is much larger) and includes
 * provisions for floating point.
 */

#define MAXOCT	11	/* Maximum octal digits in a long */
#define MAXINT	32767	/* largest normal length positive integer */
#define BIG	1000000000  /* largest power of 10 less than an unsigned long */
#define MAXDIGS	10	/* number of digits in BIG */

static int width, sign, fill;

char *_p_dconv();

/* VARARGS */
ex_printf(va_alist)
	va_dcl
{
	va_list ap;
	register char *fmt;
	char fcode;
	int prec;
	int length,mask1,nbits,n;
	long int mask2, num;
	register char *bptr;
	char *ptr;
	char buf[134];

	va_start(ap);
	fmt = va_arg(ap,char *);
	for (;;) {
		/* process format string first */
		while ((fcode = *fmt++)!='%') {
			/* ordinary (non-%) character */
			if (fcode=='\0')
				return;
			ex_putchar(fcode);
		}
		/* length modifier: -1 for h, 1 for l, 0 for none */
		length = 0;
		/* check for a leading - sign */
		sign = 0;
		if (*fmt == '-') {
			sign++;
			fmt++;
		}
		/* a '0' may follow the - sign */
		/* this is the requested fill character */
		fill = 1;
		if (*fmt == '0') {
			fill--;
			fmt++;
		}
		
		/* Now comes a digit string which may be a '*' */
		if (*fmt == '*') {
			width = va_arg(ap, int);
			if (width < 0) {
				width = -width;
				sign = !sign;
			}
			fmt++;
		}
		else {
			width = 0;
			while (*fmt>='0' && *fmt<='9')
				width = width * 10 + (*fmt++ - '0');
		}
		
		/* maybe a decimal point followed by more digits (or '*') */
		if (*fmt=='.') {
			if (*++fmt == '*') {
				prec = va_arg(ap, int);
				fmt++;
			}
			else {
				prec = 0;
				while (*fmt>='0' && *fmt<='9')
					prec = prec * 10 + (*fmt++ - '0');
			}
		}
		else
			prec = -1;
		
		/*
		 * At this point, "sign" is nonzero if there was
		 * a sign, "fill" is 0 if there was a leading
		 * zero and 1 otherwise, "width" and "prec"
		 * contain numbers corresponding to the digit
		 * strings before and after the decimal point,
		 * respectively, and "fmt" addresses the next
		 * character after the whole mess. If there was
		 * no decimal point, "prec" will be -1.
		 */
		switch (*fmt) {
			case 'L':
			case 'l':
				length = 2;
				/* no break!! */
			case 'h':
			case 'H':
				length--;
				fmt++;
				break;
		}
		
		/*
		 * At exit from the following switch, we will
		 * emit the characters starting at "bptr" and
		 * ending at "ptr"-1, unless fcode is '\0'.
		 */
		switch (fcode = *fmt++) {
			/* process characters and strings first */
			case 'c':
				buf[0] = va_arg(ap, int);
				ptr = bptr = &buf[0];
				if (buf[0] != '\0')
					ptr++;
				break;
			case 's':
				bptr = va_arg(ap,char *);
				if (bptr==0)
					bptr = "(null pointer)";
				if (prec < 0)
					prec = MAXINT;
				for (n=0; *bptr++ && n < prec; n++) ;
				ptr = --bptr;
				bptr -= n;
				break;
			case 'O':
				length = 1;
				fcode = 'o';
				/* no break */
			case 'o':
			case 'X':
			case 'x':
				if (length > 0)
					num = va_arg(ap,long);
				else
					num = (unsigned)va_arg(ap,int);
				if (fcode=='o') {
					mask1 = 0x7;
					mask2 = 0x1fffffffL;
					nbits = 3;
				}
				else {
					mask1 = 0xf;
					mask2 = 0x0fffffffL;
					nbits = 4;
				}
				n = (num!=0);
				bptr = buf + MAXOCT + 3;
				/* shift and mask for speed */
				do
				    if (((int) num & mask1) < 10)
					*--bptr = ((int) num & mask1) + 060;
				    else
					*--bptr = ((int) num & mask1) + 0127;
				while (num = (num >> nbits) & mask2);
				
				if (fcode=='o') {
					if (n)
						*--bptr = '0';
				}
				else
					if (!sign && fill <= 0) {
						ex_putchar('0');
						ex_putchar(fcode);
						width -= 2;
					}
					else {
						*--bptr = fcode;
						*--bptr = '0';
					}
				ptr = buf + MAXOCT + 3;
				break;
			case 'D':
			case 'U':
			case 'I':
				length = 1;
				fcode = fcode + 'a' - 'A';
				/* no break */
			case 'd':
			case 'i':
			case 'u':
				if (length > 0)
					num = va_arg(ap,long);
				else {
					n = va_arg(ap,int);
					if (fcode=='u')
						num = (unsigned) n;
					else
						num = (long) n;
				}
				if (n = (fcode != 'u' && num < 0))
					num = -num;
				/* now convert to digits */
				bptr = _p_dconv(num, buf);
				if (n)
					*--bptr = '-';
				if (fill == 0)
					fill = -1;
				ptr = buf + MAXDIGS + 1;
				break;
			default:
				/* not a control character, 
				 * print it.
				 */
				ptr = bptr = &fcode;
				ptr++;
				break;
			}
			if (fcode != '\0')
				_p_emit(bptr,ptr);
	}
	va_end(ap);
}

/* _p_dconv converts the unsigned long integer "value" to
 * printable decimal and places it in "buffer", right-justified.
 * The value returned is the address of the first non-zero character,
 * or the address of the last character if all are zero.
 * The result is NOT null terminated, and is MAXDIGS characters long,
 * starting at buffer[1] (to allow for insertion of a sign).
 *
 * This program assumes it is running on 2's complement machine
 * with reasonable overflow treatment.
 */
char *
_p_dconv(value, buffer)
	long value;
	char *buffer;
{
	register char *bp;
	register int svalue;
	int n;
	long lval;
	
	bp = buffer;
	
	/* zero is a special case */
	if (value == 0) {
		bp += MAXDIGS;
		*bp = '0';
		return(bp);
	}
	
	/* develop the leading digit of the value in "n" */
	n = 0;
	while (value < 0) {
		value -= BIG;	/* will eventually underflow */
		n++;
	}
	while ((lval = value - BIG) >= 0) {
		value = lval;
		n++;
	}
	
	/* stash it in buffer[1] to allow for a sign */
	bp[1] = n + '0';
	/*
	 * Now develop the rest of the digits. Since speed counts here,
	 * we do it in two loops. The first gets "value" down until it
	 * is no larger than MAXINT. The second one uses integer divides
	 * rather than long divides to speed it up.
	 */
	bp += MAXDIGS + 1;
	while (value > MAXINT) {
		*--bp = (int)(value % 10) + '0';
		value /= 10;
	}
	
	/* cannot lose precision */
	svalue = value;
	while (svalue > 0) {
		*--bp = (svalue % 10) + '0';
		svalue /= 10;
	}
	
	/* fill in intermediate zeroes if needed */
	if (buffer[1] != '0') {
		while (bp > buffer + 2)
			*--bp = '0';
		--bp;
	}
	return(bp);
}

/*
 * This program sends string "s" to putchar. The character after
 * the end of "s" is given by "send". This allows the size of the
 * field to be computed; it is stored in "alen". "width" contains the
 * user specified length. If width<alen, the width will be taken to
 * be alen. "sign" is zero if the string is to be right-justified
 * in the field, nonzero if it is to be left-justified. "fill" is
 * 0 if the string is to be padded with '0', positive if it is to be
 * padded with ' ', and negative if an initial '-' should appear before
 * any padding in right-justification (to avoid printing "-3" as
 * "000-3" where "-0003" was intended).
 */
_p_emit(s, send)
	register char *s;
	char *send;
{
	char cfill;
	register int alen;
	int npad;
	
	alen = send - s;
	if (alen > width)
		width = alen;
	cfill = fill>0? ' ': '0';
	
	/* we may want to print a leading '-' before anything */
	if (*s == '-' && fill < 0) {
		ex_putchar(*s++);
		alen--;
		width--;
	}
	npad = width - alen;
	
	/* emit any leading pad characters */
	if (!sign)
		while (--npad >= 0)
			ex_putchar(cfill);
			
	/* emit the string itself */
	while (--alen >= 0)
		ex_putchar(*s++);
		
	/* emit trailing pad characters */
	if (sign)
		while (--npad >= 0)
			ex_putchar(cfill);
}
Commit	Line	Data
edf71f48 DF	1	/*
	2	* Copyright (c) 1980 Regents of the University of California.
	3	* All rights reserved. The Berkeley software License Agreement
	4	* specifies the terms and conditions for redistribution.
	5	*/
	6
	7	#ifndef lint
5a6c967e	8	static char *sccsid = "@(#)printf.c 7.4 (Berkeley) %G%";
7c4625ef	9	/* The pwb version this is based on */
6fcce21a	10	static char *printf_id = "@(#) printf.c:2.2 6/5/79";
5a6c967e CH	11	#endif not lint
	12
	13	#include <varargs.h>
	14
5f4b8e7a MH	15	/*
	16	* This version of printf is compatible with the Version 7 C
	17	* printf. The differences are only minor except that this
	18	* printf assumes it is to print through putchar. Version 7
	19	* printf is more general (and is much larger) and includes
	20	* provisions for floating point.
	21	*/
5f4b8e7a MH	22
	23	#define MAXOCT 11 /* Maximum octal digits in a long */
	24	#define MAXINT 32767 /* largest normal length positive integer */
	25	#define BIG 1000000000 /* largest power of 10 less than an unsigned long */
	26	#define MAXDIGS 10 /* number of digits in BIG */
	27
	28	static int width, sign, fill;
	29
	30	char *_p_dconv();
	31
5a6c967e CH	32	/* VARARGS */
5a6c967e CH	33	ex_printf(va_alist)
5f4b8e7a MH	34	va_dcl
	35	{
	36	va_list ap;
	37	register char *fmt;
	38	char fcode;
	39	int prec;
	40	int length,mask1,nbits,n;
	41	long int mask2, num;
	42	register char *bptr;
	43	char *ptr;
	44	char buf[134];
	45
	46	va_start(ap);
	47	fmt = va_arg(ap,char *);
	48	for (;;) {
	49	/* process format string first */
	50	while ((fcode = *fmt++)!='%') {
	51	/* ordinary (non-%) character */
	52	if (fcode=='\0')
	53	return;
5a6c967e	54	ex_putchar(fcode);
5f4b8e7a MH	55	}
	56	/* length modifier: -1 for h, 1 for l, 0 for none */
	57	length = 0;
	58	/* check for a leading - sign */
	59	sign = 0;
	60	if (*fmt == '-') {
	61	sign++;
	62	fmt++;
	63	}
	64	/* a '0' may follow the - sign */
	65	/* this is the requested fill character */
	66	fill = 1;
	67	if (*fmt == '0') {
	68	fill--;
	69	fmt++;
	70	}
	71
	72	/* Now comes a digit string which may be a '' /
	73	if (fmt == '') {
	74	width = va_arg(ap, int);
	75	if (width < 0) {
	76	width = -width;
	77	sign = !sign;
	78	}
	79	fmt++;
	80	}
	81	else {
	82	width = 0;
	83	while (fmt>='0' && fmt<='9')
	84	width = width * 10 + (*fmt++ - '0');
	85	}
	86
	87	/* maybe a decimal point followed by more digits (or '') /
	88	if (*fmt=='.') {
	89	if (++fmt == '') {
	90	prec = va_arg(ap, int);
	91	fmt++;
	92	}
	93	else {
	94	prec = 0;
	95	while (fmt>='0' && fmt<='9')
	96	prec = prec * 10 + (*fmt++ - '0');
	97	}
	98	}
	99	else
	100	prec = -1;
	101
	102	/*
	103	* At this point, "sign" is nonzero if there was
	104	* a sign, "fill" is 0 if there was a leading
	105	* zero and 1 otherwise, "width" and "prec"
	106	* contain numbers corresponding to the digit
	107	* strings before and after the decimal point,
	108	* respectively, and "fmt" addresses the next
	109	* character after the whole mess. If there was
	110	* no decimal point, "prec" will be -1.
	111	*/
	112	switch (*fmt) {
	113	case 'L':
	114	case 'l':
	115	length = 2;
	116	/* no break!! */
	117	case 'h':
	118	case 'H':
119	length--;
120	fmt++;
121	break;
122	}
123
124	/*
125	* At exit from the following switch, we will
126	* emit the characters starting at "bptr" and
127	* ending at "ptr"-1, unless fcode is '\0'.
128	*/
129	switch (fcode = *fmt++) {
130	/* process characters and strings first */
131	case 'c':
132	buf[0] = va_arg(ap, int);
133	ptr = bptr = &buf[0];
134	if (buf[0] != '\0')
135	ptr++;
136	break;
137	case 's':
138	bptr = va_arg(ap,char *);
139	if (bptr==0)
140	bptr = "(null pointer)";
141	if (prec < 0)
142	prec = MAXINT;
143	for (n=0; *bptr++ && n < prec; n++) ;
144	ptr = --bptr;
145	bptr -= n;
146	break;
147	case 'O':
148	length = 1;
149	fcode = 'o';
150	/* no break */
151	case 'o':
152	case 'X':
153	case 'x':
154	if (length > 0)
155	num = va_arg(ap,long);
156	else
157	num = (unsigned)va_arg(ap,int);
158	if (fcode=='o') {
159	mask1 = 0x7;
160	mask2 = 0x1fffffffL;
161	nbits = 3;
162	}
163	else {
164	mask1 = 0xf;
165	mask2 = 0x0fffffffL;
166	nbits = 4;
167	}
168	n = (num!=0);
169	bptr = buf + MAXOCT + 3;
170	/* shift and mask for speed */
171	do
172	if (((int) num & mask1) < 10)
173	*--bptr = ((int) num & mask1) + 060;
174	else
175	*--bptr = ((int) num & mask1) + 0127;
176	while (num = (num >> nbits) & mask2);
177
178	if (fcode=='o') {
179	if (n)
180	*--bptr = '0';
181	}
182	else
183	if (!sign && fill <= 0) {
5a6c967e CH	184	ex_putchar('0');
5a6c967e CH	185	ex_putchar(fcode);
5f4b8e7a MH	186	width -= 2;
	187	}
	188	else {
	189	*--bptr = fcode;
	190	*--bptr = '0';
	191	}
	192	ptr = buf + MAXOCT + 3;
	193	break;
	194	case 'D':
	195	case 'U':
	196	case 'I':
	197	length = 1;
	198	fcode = fcode + 'a' - 'A';
	199	/* no break */
	200	case 'd':
	201	case 'i':
	202	case 'u':
	203	if (length > 0)
	204	num = va_arg(ap,long);
	205	else {
	206	n = va_arg(ap,int);
	207	if (fcode=='u')
	208	num = (unsigned) n;
	209	else
	210	num = (long) n;
	211	}
	212	if (n = (fcode != 'u' && num < 0))
	213	num = -num;
	214	/* now convert to digits */
	215	bptr = _p_dconv(num, buf);
	216	if (n)
	217	*--bptr = '-';
	218	if (fill == 0)
	219	fill = -1;
	220	ptr = buf + MAXDIGS + 1;
	221	break;
	222	default:
	223	/* not a control character,
	224	* print it.
	225	*/
	226	ptr = bptr = &fcode;
	227	ptr++;
	228	break;
	229	}
	230	if (fcode != '\0')
	231	_p_emit(bptr,ptr);
	232	}
	233	va_end(ap);
	234	}
	235
	236	/* _p_dconv converts the unsigned long integer "value" to
	237	* printable decimal and places it in "buffer", right-justified.
	238	* The value returned is the address of the first non-zero character,
	239	* or the address of the last character if all are zero.
	240	* The result is NOT null terminated, and is MAXDIGS characters long,
	241	* starting at buffer[1] (to allow for insertion of a sign).
	242	*
	243	* This program assumes it is running on 2's complement machine
	244	* with reasonable overflow treatment.
	245	*/
	246	char *
	247	_p_dconv(value, buffer)
	248	long value;
	249	char *buffer;
250	{
251	register char *bp;
252	register int svalue;
253	int n;
254	long lval;
255
256	bp = buffer;
257
258	/* zero is a special case */
259	if (value == 0) {
260	bp += MAXDIGS;
261	*bp = '0';
262	return(bp);
263	}
264
265	/* develop the leading digit of the value in "n" */
266	n = 0;
267	while (value < 0) {
268	value -= BIG; /* will eventually underflow */
269	n++;
270	}
271	while ((lval = value - BIG) >= 0) {
272	value = lval;
273	n++;
274	}
275
276	/* stash it in buffer[1] to allow for a sign */
277	bp[1] = n + '0';
278	/*
279	* Now develop the rest of the digits. Since speed counts here,
280	* we do it in two loops. The first gets "value" down until it
281	* is no larger than MAXINT. The second one uses integer divides
282	* rather than long divides to speed it up.
283	*/
284	bp += MAXDIGS + 1;
285	while (value > MAXINT) {
286	*--bp = (int)(value % 10) + '0';
287	value /= 10;
288	}
289
290	/* cannot lose precision */
291	svalue = value;
292	while (svalue > 0) {
293	*--bp = (svalue % 10) + '0';
294	svalue /= 10;
295	}
296
297	/* fill in intermediate zeroes if needed */
298	if (buffer[1] != '0') {
299	while (bp > buffer + 2)
300	*--bp = '0';
301	--bp;
302	}
303	return(bp);
304	}
305
306	/*
307	* This program sends string "s" to putchar. The character after
308	* the end of "s" is given by "send". This allows the size of the
309	* field to be computed; it is stored in "alen". "width" contains the
310	* user specified length. If width<alen, the width will be taken to
311	* be alen. "sign" is zero if the string is to be right-justified
312	* in the field, nonzero if it is to be left-justified. "fill" is
313	* 0 if the string is to be padded with '0', positive if it is to be
314	* padded with ' ', and negative if an initial '-' should appear before
315	* any padding in right-justification (to avoid printing "-3" as
316	* "000-3" where "-0003" was intended).
317	*/
318	_p_emit(s, send)
319	register char *s;
320	char *send;
321	{
322	char cfill;
323	register int alen;
324	int npad;
325
326	alen = send - s;
327	if (alen > width)
328	width = alen;
329	cfill = fill>0? ' ': '0';
330
331	/* we may want to print a leading '-' before anything */
332	if (*s == '-' && fill < 0) {
5a6c967e	333	ex_putchar(*s++);
5f4b8e7a MH	334	alen--;
	335	width--;
	336	}
	337	npad = width - alen;
	338
	339	/* emit any leading pad characters */
	340	if (!sign)
	341	while (--npad >= 0)
5a6c967e	342	ex_putchar(cfill);
5f4b8e7a MH	343
	344	/* emit the string itself */
	345	while (--alen >= 0)
5a6c967e	346	ex_putchar(*s++);
5f4b8e7a MH	347
	348	/* emit trailing pad characters */
	349	if (sign)
	350	while (--npad >= 0)
5a6c967e	351	ex_putchar(cfill);
5f4b8e7a	352	}