+/* 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);
+}
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