1 /* 2 * Copyright (c) 1989 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #ifndef lint 35 char copyright[] = 36 "@(#) Copyright (c) 1989 The Regents of the University of California.\n\ 37 All rights reserved.\n"; 38 #endif /* not lint */ 39 40 #ifndef lint 41 /*static char sccsid[] = "from: @(#)printf.c 5.9 (Berkeley) 6/1/90";*/ 42 static char rcsid[] = "$Id: printf.c,v 1.3 1993/08/01 18:10:03 mycroft Exp $"; 43 #endif /* not lint */ 44 45 #include <sys/types.h> 46 #include <stdio.h> 47 #include <string.h> 48 49 #define PF(f, func) { \ 50 if (fieldwidth) \ 51 if (precision) \ 52 (void)printf(f, fieldwidth, precision, func); \ 53 else \ 54 (void)printf(f, fieldwidth, func); \ 55 else if (precision) \ 56 (void)printf(f, precision, func); \ 57 else \ 58 (void)printf(f, func); \ 59 } 60 61 char **gargv; 62 63 main(argc, argv) 64 int argc; 65 char **argv; 66 { 67 static char *skip1, *skip2; 68 register char *format, *fmt, *start; 69 register int end, fieldwidth, precision; 70 char convch, nextch, *getstr(), *mklong(); 71 double getdouble(); 72 long getlong(); 73 74 if (argc < 2) { 75 fprintf(stderr, "usage: printf format [arg ...]\n"); 76 exit(1); 77 } 78 79 /* 80 * Basic algorithm is to scan the format string for conversion 81 * specifications -- once one is found, find out if the field 82 * width or precision is a '*'; if it is, gather up value. Note, 83 * format strings are reused as necessary to use up the provided 84 * arguments, arguments of zero/null string are provided to use 85 * up the format string. 86 */ 87 skip1 = "#-+ 0"; 88 skip2 = "*0123456789"; 89 90 escape(fmt = format = *++argv); /* backslash interpretation */ 91 gargv = ++argv; 92 for (;;) { 93 end = 0; 94 /* find next format specification */ 95 next: for (start = fmt;; ++fmt) { 96 if (!*fmt) { 97 /* avoid infinite loop */ 98 if (end == 1) { 99 fprintf(stderr, 100 "printf: missing format character.\n"); 101 exit(1); 102 } 103 end = 1; 104 if (fmt > start) 105 (void)printf("%s", start); 106 if (!*gargv) 107 exit(0); 108 fmt = format; 109 goto next; 110 } 111 /* %% prints a % */ 112 if (*fmt == '%') { 113 if (*++fmt != '%') 114 break; 115 *fmt++ = '\0'; 116 (void)printf("%s", start); 117 goto next; 118 } 119 } 120 121 /* skip to field width */ 122 for (; index(skip1, *fmt); ++fmt); 123 fieldwidth = *fmt == '*' ? getint() : 0; 124 125 /* skip to possible '.', get following precision */ 126 for (; index(skip2, *fmt); ++fmt); 127 if (*fmt == '.') 128 ++fmt; 129 precision = *fmt == '*' ? getint() : 0; 130 131 /* skip to conversion char */ 132 for (; index(skip2, *fmt); ++fmt); 133 if (!*fmt) { 134 fprintf(stderr, "printf: missing format character.\n"); 135 exit(1); 136 } 137 138 convch = *fmt; 139 nextch = *++fmt; 140 *fmt = '\0'; 141 switch(convch) { 142 case 'c': { 143 char p = getchr(); 144 PF(start, p); 145 break; 146 } 147 case 's': { 148 char *p = getstr(); 149 PF(start, p); 150 break; 151 } 152 case 'd': case 'i': case 'o': case 'u': case 'x': case 'X': { 153 char *f = mklong(start, convch); 154 long p = getlong(); 155 PF(f, p); 156 break; 157 } 158 case 'e': case 'E': case 'f': case 'g': case 'G': { 159 double p = getdouble(); 160 PF(start, p); 161 break; 162 } 163 default: 164 fprintf(stderr, "printf: illegal format character.\n"); 165 exit(1); 166 } 167 *fmt = nextch; 168 } 169 /* NOTREACHED */ 170 } 171 172 char * 173 mklong(str, ch) 174 char *str, ch; 175 { 176 int len; 177 char *copy, *malloc(); 178 179 len = strlen(str) + 2; 180 if (!(copy = malloc((u_int)len))) { /* never freed; XXX */ 181 fprintf(stderr, "printf: out of memory.\n"); 182 exit(1); 183 } 184 bcopy(str, copy, len - 3); 185 copy[len - 3] = 'l'; 186 copy[len - 2] = ch; 187 copy[len - 1] = '\0'; 188 return(copy); 189 } 190 191 escape(fmt) 192 register char *fmt; 193 { 194 register char *store; 195 register int value, c; 196 197 for (store = fmt; c = *fmt; ++fmt, ++store) { 198 if (c != '\\') { 199 *store = c; 200 continue; 201 } 202 switch (*++fmt) { 203 case '\0': /* EOS, user error */ 204 *store = '\\'; 205 *++store = '\0'; 206 return; 207 case '\\': /* backslash */ 208 case '\'': /* single quote */ 209 *store = *fmt; 210 break; 211 case 'a': /* bell/alert */ 212 *store = '\7'; 213 break; 214 case 'b': /* backspace */ 215 *store = '\b'; 216 break; 217 case 'f': /* form-feed */ 218 *store = '\f'; 219 break; 220 case 'n': /* newline */ 221 *store = '\n'; 222 break; 223 case 'r': /* carriage-return */ 224 *store = '\r'; 225 break; 226 case 't': /* horizontal tab */ 227 *store = '\t'; 228 break; 229 case 'v': /* vertical tab */ 230 *store = '\13'; 231 break; 232 /* octal constant */ 233 case '0': case '1': case '2': case '3': 234 case '4': case '5': case '6': case '7': 235 for (c = 3, value = 0; 236 c-- && *fmt >= '0' && *fmt <= '7'; ++fmt) { 237 value <<= 3; 238 value += *fmt - '0'; 239 } 240 --fmt; 241 *store = value; 242 break; 243 default: 244 *store = *fmt; 245 break; 246 } 247 } 248 *store = '\0'; 249 } 250 251 getchr() 252 { 253 if (!*gargv) 254 return((int)'\0'); 255 return((int)**gargv++); 256 } 257 258 char * 259 getstr() 260 { 261 if (!*gargv) 262 return(""); 263 return(*gargv++); 264 } 265 266 static char *number = "+-.0123456789"; 267 getint() 268 { 269 if (!*gargv) 270 return(0); 271 if (index(number, **gargv)) 272 return(atoi(*gargv++)); 273 return(asciicode()); 274 } 275 276 long 277 getlong() 278 { 279 long atol(); 280 281 if (!*gargv) 282 return((long)0); 283 if (index(number, **gargv)) 284 return(strtol(*gargv++, (char **)NULL, 0)); 285 return((long)asciicode()); 286 } 287 288 double 289 getdouble() 290 { 291 double atof(); 292 293 if (!*gargv) 294 return((double)0); 295 if (index(number, **gargv)) 296 return(atof(*gargv++)); 297 return((double)asciicode()); 298 } 299 300 asciicode() 301 { 302 register char ch; 303 304 ch = **gargv; 305 if (ch == '\'' || ch == '"') 306 ch = (*gargv)[1]; 307 ++gargv; 308 return(ch); 309 } 310