1 /* $NetBSD: subr_prf.c,v 1.15 2006/01/27 02:28:36 uwe Exp $ */ 2 3 /*- 4 * Copyright (c) 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)printf.c 8.1 (Berkeley) 6/11/93 32 */ 33 34 /* 35 * Scaled down version of printf(3). 36 */ 37 38 #include <sys/cdefs.h> 39 #include <sys/types.h> 40 #include <sys/stdint.h> /* XXX: for intptr_t */ 41 #include <machine/stdarg.h> 42 43 #include "stand.h" 44 45 static void kprintn(void (*)(int), u_long, int); 46 static void sputchar(int); 47 static void kdoprnt(void (*)(int), const char *, va_list); 48 49 static char *sbuf, *ebuf; 50 51 const char HEXDIGITS[] = "0123456789ABCDEF"; 52 const char hexdigits[] = "0123456789abcdef"; 53 54 static void 55 sputchar(int c) 56 { 57 58 if (sbuf < ebuf) 59 *sbuf++ = c; 60 } 61 62 void 63 vprintf(const char *fmt, va_list ap) 64 { 65 66 kdoprnt(putchar, fmt, ap); 67 } 68 69 int 70 vsnprintf(char *buf, size_t size, const char *fmt, va_list ap) 71 { 72 73 sbuf = buf; 74 ebuf = buf + size - 1; 75 kdoprnt(sputchar, fmt, ap); 76 *sbuf = '\0'; 77 return (sbuf - buf); 78 } 79 80 static void 81 kdoprnt(void (*put)(int), const char *fmt, va_list ap) 82 { 83 char *p; 84 int ch; 85 unsigned long ul; 86 int lflag; 87 88 for (;;) { 89 while ((ch = *fmt++) != '%') { 90 if (ch == '\0') 91 return; 92 put(ch); 93 } 94 lflag = 0; 95 reswitch: switch (ch = *fmt++) { 96 case 'l': 97 lflag = 1; 98 goto reswitch; 99 case 't': 100 #if 0 /* XXX: abuse intptr_t until the situation with ptrdiff_t is clear */ 101 lflag = (sizeof(ptrdiff_t) == sizeof(long)); 102 #else 103 lflag = (sizeof(intptr_t) == sizeof(long)); 104 #endif 105 goto reswitch; 106 case 'z': 107 lflag = (sizeof(size_t) == sizeof(unsigned long)); 108 goto reswitch; 109 case 'c': 110 ch = va_arg(ap, int); 111 put(ch & 0x7f); 112 break; 113 case 's': 114 p = va_arg(ap, char *); 115 while ((ch = *p++)) 116 put(ch); 117 break; 118 case 'd': 119 ul = lflag ? 120 va_arg(ap, long) : va_arg(ap, int); 121 if ((long)ul < 0) { 122 put('-'); 123 ul = -(long)ul; 124 } 125 kprintn(put, ul, 10); 126 break; 127 case 'o': 128 ul = lflag ? 129 va_arg(ap, u_long) : va_arg(ap, u_int); 130 kprintn(put, ul, 8); 131 break; 132 case 'u': 133 ul = lflag ? 134 va_arg(ap, u_long) : va_arg(ap, u_int); 135 kprintn(put, ul, 10); 136 break; 137 case 'p': 138 put('0'); 139 put('x'); 140 lflag = 1; 141 /* FALLTHROUGH */ 142 case 'x': 143 ul = lflag ? 144 va_arg(ap, u_long) : va_arg(ap, u_int); 145 kprintn(put, ul, 16); 146 break; 147 default: 148 put('%'); 149 if (lflag) 150 put('l'); 151 if (ch == '\0') 152 return; 153 put(ch); 154 } 155 } 156 } 157 158 static void 159 kprintn(void (*put)(int), unsigned long ul, int base) 160 { 161 /* hold a long in base 8 */ 162 char *p, buf[(sizeof(long) * NBBY / 3) + 1]; 163 164 p = buf; 165 do { 166 *p++ = hexdigits[ul % base]; 167 } while (ul /= base); 168 do { 169 put(*--p); 170 } while (p > buf); 171 } 172