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[] = "@(#)printf.c 5.9 (Berkeley) 6/1/90"; 42 #endif /* not lint */ 43 44 #include <sys/types.h> 45 #include <stdio.h> 46 #include <string.h> 47 48 #define PF(f, func) { \ 49 if (fieldwidth) \ 50 if (precision) \ 51 (void)printf(f, fieldwidth, precision, func); \ 52 else \ 53 (void)printf(f, fieldwidth, func); \ 54 else if (precision) \ 55 (void)printf(f, precision, func); \ 56 else \ 57 (void)printf(f, func); \ 58 } 59 60 char **gargv; 61 62 main(argc, argv) 63 int argc; 64 char **argv; 65 { 66 static char *skip1, *skip2; 67 register char *format, *fmt, *start; 68 register int end, fieldwidth, precision; 69 char convch, nextch, *getstr(), *mklong(); 70 double getdouble(); 71 long getlong(); 72 73 if (argc < 2) { 74 fprintf(stderr, "usage: printf format [arg ...]\n"); 75 exit(1); 76 } 77 78 /* 79 * Basic algorithm is to scan the format string for conversion 80 * specifications -- once one is found, find out if the field 81 * width or precision is a '*'; if it is, gather up value. Note, 82 * format strings are reused as necessary to use up the provided 83 * arguments, arguments of zero/null string are provided to use 84 * up the format string. 85 */ 86 skip1 = "#-+ 0"; 87 skip2 = "*0123456789"; 88 89 escape(fmt = format = *++argv); /* backslash interpretation */ 90 gargv = ++argv; 91 for (;;) { 92 end = 0; 93 /* find next format specification */ 94 next: for (start = fmt;; ++fmt) { 95 if (!*fmt) { 96 /* avoid infinite loop */ 97 if (end == 1) { 98 fprintf(stderr, 99 "printf: missing format character.\n"); 100 exit(1); 101 } 102 end = 1; 103 if (fmt > start) 104 (void)printf("%s", start); 105 if (!*gargv) 106 exit(0); 107 fmt = format; 108 goto next; 109 } 110 /* %% prints a % */ 111 if (*fmt == '%') { 112 if (*++fmt != '%') 113 break; 114 *fmt++ = '\0'; 115 (void)printf("%s", start); 116 goto next; 117 } 118 } 119 120 /* skip to field width */ 121 for (; index(skip1, *fmt); ++fmt); 122 fieldwidth = *fmt == '*' ? getint() : 0; 123 124 /* skip to possible '.', get following precision */ 125 for (; index(skip2, *fmt); ++fmt); 126 if (*fmt == '.') 127 ++fmt; 128 precision = *fmt == '*' ? getint() : 0; 129 130 /* skip to conversion char */ 131 for (; index(skip2, *fmt); ++fmt); 132 if (!*fmt) { 133 fprintf(stderr, "printf: missing format character.\n"); 134 exit(1); 135 } 136 137 convch = *fmt; 138 nextch = *++fmt; 139 *fmt = '\0'; 140 switch(convch) { 141 case 'c': { 142 char p = getchr(); 143 PF(start, p); 144 break; 145 } 146 case 's': { 147 char *p = getstr(); 148 PF(start, p); 149 break; 150 } 151 case 'd': case 'i': case 'o': case 'u': case 'x': case 'X': { 152 char *f = mklong(start, convch); 153 long p = getlong(); 154 PF(f, p); 155 break; 156 } 157 case 'e': case 'E': case 'f': case 'g': case 'G': { 158 double p = getdouble(); 159 PF(start, p); 160 break; 161 } 162 default: 163 fprintf(stderr, "printf: illegal format character.\n"); 164 exit(1); 165 } 166 *fmt = nextch; 167 } 168 /* NOTREACHED */ 169 } 170 171 char * 172 mklong(str, ch) 173 char *str, ch; 174 { 175 int len; 176 char *copy, *malloc(); 177 178 len = strlen(str) + 2; 179 if (!(copy = malloc((u_int)len))) { /* never freed; XXX */ 180 fprintf(stderr, "printf: out of memory.\n"); 181 exit(1); 182 } 183 bcopy(str, copy, len - 3); 184 copy[len - 3] = 'l'; 185 copy[len - 2] = ch; 186 copy[len - 1] = '\0'; 187 return(copy); 188 } 189 190 escape(fmt) 191 register char *fmt; 192 { 193 register char *store; 194 register int value, c; 195 196 for (store = fmt; c = *fmt; ++fmt, ++store) { 197 if (c != '\\') { 198 *store = c; 199 continue; 200 } 201 switch (*++fmt) { 202 case '\0': /* EOS, user error */ 203 *store = '\\'; 204 *++store = '\0'; 205 return; 206 case '\\': /* backslash */ 207 case '\'': /* single quote */ 208 *store = *fmt; 209 break; 210 case 'a': /* bell/alert */ 211 *store = '\7'; 212 break; 213 case 'b': /* backspace */ 214 *store = '\b'; 215 break; 216 case 'f': /* form-feed */ 217 *store = '\f'; 218 break; 219 case 'n': /* newline */ 220 *store = '\n'; 221 break; 222 case 'r': /* carriage-return */ 223 *store = '\r'; 224 break; 225 case 't': /* horizontal tab */ 226 *store = '\t'; 227 break; 228 case 'v': /* vertical tab */ 229 *store = '\13'; 230 break; 231 /* octal constant */ 232 case '0': case '1': case '2': case '3': 233 case '4': case '5': case '6': case '7': 234 for (c = 3, value = 0; 235 c-- && *fmt >= '0' && *fmt <= '7'; ++fmt) { 236 value <<= 3; 237 value += *fmt - '0'; 238 } 239 --fmt; 240 *store = value; 241 break; 242 default: 243 *store = *fmt; 244 break; 245 } 246 } 247 *store = '\0'; 248 } 249 250 getchr() 251 { 252 if (!*gargv) 253 return((int)'\0'); 254 return((int)**gargv++); 255 } 256 257 char * 258 getstr() 259 { 260 if (!*gargv) 261 return(""); 262 return(*gargv++); 263 } 264 265 static char *number = "+-.0123456789"; 266 getint() 267 { 268 if (!*gargv) 269 return(0); 270 if (index(number, **gargv)) 271 return(atoi(*gargv++)); 272 return(asciicode()); 273 } 274 275 long 276 getlong() 277 { 278 long atol(); 279 280 if (!*gargv) 281 return((long)0); 282 if (index(number, **gargv)) 283 return(strtol(*gargv++, (char **)NULL, 0)); 284 return((long)asciicode()); 285 } 286 287 double 288 getdouble() 289 { 290 double atof(); 291 292 if (!*gargv) 293 return((double)0); 294 if (index(number, **gargv)) 295 return(atof(*gargv++)); 296 return((double)asciicode()); 297 } 298 299 asciicode() 300 { 301 register char ch; 302 303 ch = **gargv; 304 if (ch == '\'' || ch == '"') 305 ch = (*gargv)[1]; 306 ++gargv; 307 return(ch); 308 } 309