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-rw-r--r--user/lib/libc/vsnprintf.c566
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diff --git a/user/lib/libc/vsnprintf.c b/user/lib/libc/vsnprintf.c
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+/*
+ ****************************************************************************
+ * (C) 2003 - Rolf Neugebauer - Intel Research Cambridge
+ ****************************************************************************
+ *
+ * File: printf.c
+ * Author: Rolf Neugebauer (neugebar@dcs.gla.ac.uk)
+ * Changes: Grzegorz Milos (gm281@cam.ac.uk)
+ *
+ * Date: Aug 2003, Aug 2005
+ *
+ * Environment: Xen Minimal OS
+ * Description: Library functions for printing
+ * (freebsd port, mainly sys/subr_prf.c)
+ *
+ ****************************************************************************
+ *
+ *-
+ * Copyright (c) 1992, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * This software was developed by the Computer Systems Engineering group
+ * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
+ * contributed to Berkeley.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD: src/sys/libkern/divdi3.c,v 1.6 1999/08/28 00:46:31 peter Exp $
+ */
+
+#include "ctype.h"
+#include "stdarg.h"
+#include "stdio.h"
+#include "string.h"
+
+static int skip_atoi(const char **s)
+{
+ int i = 0;
+
+ while (isdigit(**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' */
+
+static char *number(char *buf, char *end, long long num, int base, int size,
+ int precision, int type)
+{
+ char c, sign, tmp[66];
+ const char *digits;
+ const char small_digits[] = "0123456789abcdefghijklmnopqrstuvwxyz";
+ const char large_digits[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+ int i;
+
+ digits = (type & LARGE) ? large_digits : small_digits;
+ if (type & LEFT)
+ {
+ type &= ~ZEROPAD;
+ }
+ if (base < 2 || base > 36)
+ {
+ return buf;
+ }
+ 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
+ {
+ /* XXX KAF: force unsigned mod and div. */
+ /* XXX kernel does not support long long division */
+ unsigned long long num2 = (unsigned long long)num;
+ unsigned int base2 = (unsigned int)base;
+ while (num2 != 0)
+ {
+ tmp[i++] = digits[num2 % base2];
+ num2 /= base2;
+ }
+ }
+ if (i > precision)
+ {
+ precision = i;
+ }
+ size -= precision;
+ if (!(type & (ZEROPAD + LEFT)))
+ {
+ while (size-- > 0)
+ {
+ if (buf <= end)
+ {
+ *buf = ' ';
+ }
+ ++buf;
+ }
+ }
+ if (sign)
+ {
+ if (buf <= end)
+ {
+ *buf = sign;
+ }
+ ++buf;
+ }
+ if (type & SPECIAL)
+ {
+ if (base == 8)
+ {
+ if (buf <= end)
+ {
+ *buf = '0';
+ }
+ ++buf;
+ }
+ else if (base == 16)
+ {
+ if (buf <= end)
+ {
+ *buf = '0';
+ }
+ ++buf;
+ if (buf <= end)
+ {
+ *buf = digits[33];
+ }
+ ++buf;
+ }
+ }
+ if (!(type & LEFT))
+ {
+ while (size-- > 0)
+ {
+ if (buf <= end)
+ {
+ *buf = c;
+ }
+ ++buf;
+ }
+ }
+ while (i < precision--)
+ {
+ if (buf <= end)
+ {
+ *buf = '0';
+ }
+ ++buf;
+ }
+ while (i-- > 0)
+ {
+ if (buf <= end)
+ {
+ *buf = tmp[i];
+ }
+ ++buf;
+ }
+ while (size-- > 0)
+ {
+ if (buf <= end)
+ {
+ *buf = ' ';
+ }
+ ++buf;
+ }
+ return buf;
+}
+
+/* TODO This is a copy of the kernel vsnprintf. It has (almost)
+ * no error checking. It also is completely unable to handle
+ * floating point. - alvin */
+/**
+ * vsnprintf - Format a string and place it in a buffer
+ * @buf: The buffer to place the result into
+ * @size: The size of the buffer, including the trailing null space
+ * @fmt: The format string to use
+ * @args: Arguments for the format string
+ *
+ * Call this function if you are already dealing with a va_list.
+ * You probably want snprintf instead.
+ */
+int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
+{
+ int len;
+ unsigned long long num;
+ int i, base;
+ char *str, *end, c;
+ 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 */
+ /* 'z' support added 23/7/1999 S.H. */
+ /* 'z' changed to 'Z' --davidm 1/25/99 */
+
+ str = buf;
+ end = buf + size - 1;
+
+ if (end < buf - 1)
+ {
+ end = ((void *)-1);
+ size = end - buf + 1;
+ }
+
+ for (; *fmt; ++fmt)
+ {
+ if (*fmt != '%')
+ {
+ if (str <= end)
+ {
+ *str = *fmt;
+ }
+ ++str;
+ 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 (isdigit(*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 (isdigit(*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' || *fmt == 'Z')
+ {
+ qualifier = *fmt;
+ ++fmt;
+ if (qualifier == 'l' && *fmt == 'l')
+ {
+ qualifier = 'L';
+ ++fmt;
+ }
+ }
+ if (*fmt == 'q')
+ {
+ qualifier = 'L';
+ ++fmt;
+ }
+
+ /* default base */
+ base = 10;
+
+ switch (*fmt)
+ {
+ case 'c':
+ if (!(flags & LEFT))
+ {
+ while (--field_width > 0)
+ {
+ if (str <= end)
+ {
+ *str = ' ';
+ }
+ ++str;
+ }
+ }
+ c = (unsigned char)va_arg(args, int);
+ if (str <= end)
+ {
+ *str = c;
+ }
+ ++str;
+ while (--field_width > 0)
+ {
+ if (str <= end)
+ {
+ *str = ' ';
+ }
+ ++str;
+ }
+ continue;
+
+ case 's':
+ s = va_arg(args, char *);
+ if (!s)
+ {
+ s = "<NULL>";
+ }
+
+ len = strnlen(s, precision);
+
+ if (!(flags & LEFT))
+ {
+ while (len < field_width--)
+ {
+ if (str <= end)
+ {
+ *str = ' ';
+ }
+ ++str;
+ }
+ }
+ for (i = 0; i < len; ++i)
+ {
+ if (str <= end)
+ {
+ *str = *s;
+ }
+ ++str;
+ ++s;
+ }
+ while (len < field_width--)
+ {
+ if (str <= end)
+ {
+ *str = ' ';
+ }
+ ++str;
+ }
+ continue;
+
+ case 'p':
+ if (field_width == -1)
+ {
+ field_width = 2 * sizeof(void *);
+ flags |= ZEROPAD;
+ }
+ str = number(str, end, (unsigned long)va_arg(args, void *), 16,
+ field_width, precision, flags);
+ continue;
+
+ case 'n':
+ /* FIXME:
+ * What does C99 say about the overflow case here? */
+ if (qualifier == 'l')
+ {
+ long *ip = va_arg(args, long *);
+ *ip = (str - buf);
+ }
+ else if (qualifier == 'Z')
+ {
+ size_t *ip = va_arg(args, size_t *);
+ *ip = (str - buf);
+ }
+ else
+ {
+ int *ip = va_arg(args, int *);
+ *ip = (str - buf);
+ }
+ continue;
+
+ case '%':
+ if (str <= end)
+ {
+ *str = '%';
+ }
+ ++str;
+ continue;
+
+ /* integer number formats - set up the flags and "break" */
+ case 'o':
+ base = 8;
+ break;
+
+ case 'X':
+ flags |= LARGE;
+ base = 16;
+ break;
+ case 'x':
+ base = 16;
+ break;
+
+ case 'd':
+ case 'i':
+ flags |= SIGN;
+ case 'u':
+ break;
+ /* Added - TODO - alvin */
+ case 'f':
+ case 'F':
+ case 'g':
+ case 'G':
+ return -1;
+
+ default:
+ if (str <= end)
+ {
+ *str = '%';
+ }
+ ++str;
+ if (*fmt)
+ {
+ if (str <= end)
+ {
+ *str = *fmt;
+ }
+ ++str;
+ }
+ else
+ {
+ --fmt;
+ }
+ continue;
+ }
+ if (qualifier == 'L')
+ {
+ num = va_arg(args, long long);
+ }
+ else if (qualifier == 'l')
+ {
+ num = va_arg(args, unsigned long);
+ if (flags & SIGN)
+ {
+ num = (signed long)num;
+ }
+ }
+ else if (qualifier == 'Z')
+ {
+ num = va_arg(args, size_t);
+ }
+ else if (qualifier == 'h')
+ {
+ num = (unsigned short)va_arg(args, int);
+ if (flags & SIGN)
+ {
+ num = (signed short)num;
+ }
+ }
+ else
+ {
+ num = va_arg(args, unsigned int);
+ if (flags & SIGN)
+ {
+ num = (signed int)num;
+ }
+ }
+
+ str = number(str, end, num, base, field_width, precision, flags);
+ }
+ if (str <= end)
+ {
+ *str = '\0';
+ }
+ else if (size > 0)
+ {
+ /* don't write out a null byte if the buf size is zero */
+ *end = '\0';
+ }
+ /* the trailing null byte doesn't count towards the total
+ * ++str;
+ */
+ return str - buf;
+}
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