[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	7.3 (Berkeley) %G%";
#endif not lint

/* The pwb version this is based on */
static char *printf_id = "@(#) printf.c:2.2 6/5/79";
#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();

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;
			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) {
						putchar('0');
						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) {
		putchar(*s++);
		alen--;
		width--;
	}
	npad = width - alen;
	
	/* emit any leading pad characters */
	if (!sign)
		while (--npad >= 0)
			putchar(cfill);
			
	/* emit the string itself */
	while (--alen >= 0)
		putchar(*s++);
		
	/* emit trailing pad characters */
	if (sign)
		while (--npad >= 0)
			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
70190965	8	static char *sccsid = "@(#)printf.c 7.3 (Berkeley) %G%";
edf71f48 DF	9	#endif not lint
edf71f48 DF	10
7c4625ef	11	/* The pwb version this is based on */
6fcce21a	12	static char *printf_id = "@(#) printf.c:2.2 6/5/79";
5f4b8e7a MH	13	#include "varargs.h"
	14	/*
	15	* This version of printf is compatible with the Version 7 C
	16	* printf. The differences are only minor except that this
	17	* printf assumes it is to print through putchar. Version 7
	18	* printf is more general (and is much larger) and includes
	19	* provisions for floating point.
	20	*/
	21
	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
	32	printf(va_alist)
	33	va_dcl
	34	{
	35	va_list ap;
	36	register char *fmt;
	37	char fcode;
	38	int prec;
	39	int length,mask1,nbits,n;
	40	long int mask2, num;
	41	register char *bptr;
	42	char *ptr;
	43	char buf[134];
	44
	45	va_start(ap);
	46	fmt = va_arg(ap,char *);
	47	for (;;) {
	48	/* process format string first */
	49	while ((fcode = *fmt++)!='%') {
	50	/* ordinary (non-%) character */
	51	if (fcode=='\0')
	52	return;
	53	putchar(fcode);
	54	}
	55	/* length modifier: -1 for h, 1 for l, 0 for none */
	56	length = 0;
	57	/* check for a leading - sign */
	58	sign = 0;
	59	if (*fmt == '-') {
	60	sign++;
	61	fmt++;
	62	}
	63	/* a '0' may follow the - sign */
	64	/* this is the requested fill character */
	65	fill = 1;
	66	if (*fmt == '0') {
	67	fill--;
	68	fmt++;
	69	}
	70
	71	/* Now comes a digit string which may be a '' /
	72	if (fmt == '') {
	73	width = va_arg(ap, int);
	74	if (width < 0) {
	75	width = -width;
	76	sign = !sign;
77	}
78	fmt++;
79	}
80	else {
81	width = 0;
82	while (fmt>='0' && fmt<='9')
83	width = width * 10 + (*fmt++ - '0');
84	}
85
86	/* maybe a decimal point followed by more digits (or '') /
87	if (*fmt=='.') {
88	if (++fmt == '') {
89	prec = va_arg(ap, int);
90	fmt++;
91	}
92	else {
93	prec = 0;
94	while (fmt>='0' && fmt<='9')
95	prec = prec * 10 + (*fmt++ - '0');
96	}
97	}
98	else
99	prec = -1;
100
101	/*
102	* At this point, "sign" is nonzero if there was
103	* a sign, "fill" is 0 if there was a leading
104	* zero and 1 otherwise, "width" and "prec"
105	* contain numbers corresponding to the digit
106	* strings before and after the decimal point,
107	* respectively, and "fmt" addresses the next
108	* character after the whole mess. If there was
109	* no decimal point, "prec" will be -1.
110	*/
111	switch (*fmt) {
112	case 'L':
113	case 'l':
114	length = 2;
115	/* no break!! */
116	case 'h':
117	case 'H':
118	length--;
119	fmt++;
120	break;
121	}
122
123	/*
124	* At exit from the following switch, we will
125	* emit the characters starting at "bptr" and
126	* ending at "ptr"-1, unless fcode is '\0'.
127	*/
128	switch (fcode = *fmt++) {
129	/* process characters and strings first */
130	case 'c':
131	buf[0] = va_arg(ap, int);
132	ptr = bptr = &buf[0];
133	if (buf[0] != '\0')
134	ptr++;
135	break;
136	case 's':
137	bptr = va_arg(ap,char *);
138	if (bptr==0)
139	bptr = "(null pointer)";
140	if (prec < 0)
141	prec = MAXINT;
142	for (n=0; *bptr++ && n < prec; n++) ;
143	ptr = --bptr;
144	bptr -= n;
145	break;
146	case 'O':
147	length = 1;
148	fcode = 'o';
149	/* no break */
150	case 'o':
151	case 'X':
152	case 'x':
153	if (length > 0)
154	num = va_arg(ap,long);
155	else
156	num = (unsigned)va_arg(ap,int);
157	if (fcode=='o') {
158	mask1 = 0x7;
159	mask2 = 0x1fffffffL;
160	nbits = 3;
161	}
162	else {
163	mask1 = 0xf;
164	mask2 = 0x0fffffffL;
165	nbits = 4;
166	}
167	n = (num!=0);
168	bptr = buf + MAXOCT + 3;
169	/* shift and mask for speed */
170	do
171	if (((int) num & mask1) < 10)
172	*--bptr = ((int) num & mask1) + 060;
173	else
174	*--bptr = ((int) num & mask1) + 0127;
175	while (num = (num >> nbits) & mask2);
176
177	if (fcode=='o') {
178	if (n)
179	*--bptr = '0';
180	}
181	else
182	if (!sign && fill <= 0) {
183	putchar('0');
184	putchar(fcode);
185	width -= 2;
186	}
187	else {
188	*--bptr = fcode;
189	*--bptr = '0';
190	}
191	ptr = buf + MAXOCT + 3;
192	break;
193	case 'D':
194	case 'U':
195	case 'I':
196	length = 1;
197	fcode = fcode + 'a' - 'A';
198	/* no break */
199	case 'd':
200	case 'i':
201	case 'u':
202	if (length > 0)
203	num = va_arg(ap,long);
204	else {
205	n = va_arg(ap,int);
206	if (fcode=='u')
207	num = (unsigned) n;
208	else
209	num = (long) n;
210	}
211	if (n = (fcode != 'u' && num < 0))
212	num = -num;
213	/* now convert to digits */
214	bptr = _p_dconv(num, buf);
215	if (n)
216	*--bptr = '-';
217	if (fill == 0)
218	fill = -1;
219	ptr = buf + MAXDIGS + 1;
220	break;
221	default:
222	/* not a control character,
223	* print it.
224	*/
225	ptr = bptr = &fcode;
226	ptr++;
227	break;
228	}
229	if (fcode != '\0')
230	_p_emit(bptr,ptr);
231	}
232	va_end(ap);
233	}
234
235	/* _p_dconv converts the unsigned long integer "value" to
236	* printable decimal and places it in "buffer", right-justified.
237	* The value returned is the address of the first non-zero character,
238	* or the address of the last character if all are zero.
239	* The result is NOT null terminated, and is MAXDIGS characters long,
240	* starting at buffer[1] (to allow for insertion of a sign).
241	*
242	* This program assumes it is running on 2's complement machine
243	* with reasonable overflow treatment.
244	*/
245	char *
246	_p_dconv(value, buffer)
247	long value;
248	char *buffer;
249	{
250	register char *bp;
251	register int svalue;
252	int n;
253	long lval;
254
255	bp = buffer;
256
257	/* zero is a special case */
258	if (value == 0) {
259	bp += MAXDIGS;
260	*bp = '0';
261	return(bp);
262	}
263
264	/* develop the leading digit of the value in "n" */
265	n = 0;
266	while (value < 0) {
267	value -= BIG; /* will eventually underflow */
268	n++;
269	}
270	while ((lval = value - BIG) >= 0) {
271	value = lval;
272	n++;
273	}
274
275	/* stash it in buffer[1] to allow for a sign */
276	bp[1] = n + '0';
277	/*
278	* Now develop the rest of the digits. Since speed counts here,
279	* we do it in two loops. The first gets "value" down until it
280	* is no larger than MAXINT. The second one uses integer divides
281	* rather than long divides to speed it up.
282	*/
283	bp += MAXDIGS + 1;
284	while (value > MAXINT) {
285	*--bp = (int)(value % 10) + '0';
286	value /= 10;
287	}
288
289	/* cannot lose precision */
290	svalue = value;
291	while (svalue > 0) {
292	*--bp = (svalue % 10) + '0';
293	svalue /= 10;
294	}
295
296	/* fill in intermediate zeroes if needed */
297	if (buffer[1] != '0') {
298	while (bp > buffer + 2)
299	*--bp = '0';
300	--bp;
301	}
302	return(bp);
303	}
304
305	/*
306	* This program sends string "s" to putchar. The character after
307	* the end of "s" is given by "send". This allows the size of the
308	* field to be computed; it is stored in "alen". "width" contains the
309	* user specified length. If width<alen, the width will be taken to
310	* be alen. "sign" is zero if the string is to be right-justified
311	* in the field, nonzero if it is to be left-justified. "fill" is
312	* 0 if the string is to be padded with '0', positive if it is to be
313	* padded with ' ', and negative if an initial '-' should appear before
314	* any padding in right-justification (to avoid printing "-3" as
315	* "000-3" where "-0003" was intended).
316	*/
317	_p_emit(s, send)
318	register char *s;
319	char *send;
320	{
321	char cfill;
322	register int alen;
323	int npad;
324
325	alen = send - s;
326	if (alen > width)
327	width = alen;
328	cfill = fill>0? ' ': '0';
329
330	/* we may want to print a leading '-' before anything */
331	if (*s == '-' && fill < 0) {
332	putchar(*s++);
333	alen--;
334	width--;
335	}
336	npad = width - alen;
337
338	/* emit any leading pad characters */
339	if (!sign)
340	while (--npad >= 0)
341	putchar(cfill);
342
343	/* emit the string itself */
344	while (--alen >= 0)
345	putchar(*s++);
346
347	/* emit trailing pad characters */
348	if (sign)
349	while (--npad >= 0)
350	putchar(cfill);
351	}