main.c revision 1.6
1 /* $NetBSD: main.c,v 1.6 2003/08/07 09:28:00 agc Exp $ */ 2 3 /* 4 * Copyright (c) 1988, 1993 5 * 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 32 /* 33 * Copyright (c) 1988 Mark Nudleman 34 * 35 * Redistribution and use in source and binary forms, with or without 36 * modification, are permitted provided that the following conditions 37 * are met: 38 * 1. Redistributions of source code must retain the above copyright 39 * notice, this list of conditions and the following disclaimer. 40 * 2. Redistributions in binary form must reproduce the above copyright 41 * notice, this list of conditions and the following disclaimer in the 42 * documentation and/or other materials provided with the distribution. 43 * 3. All advertising materials mentioning features or use of this software 44 * must display the following acknowledgement: 45 * This product includes software developed by the University of 46 * California, Berkeley and its contributors. 47 * 4. Neither the name of the University nor the names of its contributors 48 * may be used to endorse or promote products derived from this software 49 * without specific prior written permission. 50 * 51 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 52 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 53 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 54 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 55 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 56 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 57 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 58 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 59 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 60 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 61 * SUCH DAMAGE. 62 */ 63 64 #include <sys/cdefs.h> 65 #ifndef lint 66 __COPYRIGHT( 67 "@(#) Copyright (c) 1988 Mark Nudleman.\n\ 68 @(#) Copyright (c) 1988, 1993 69 Regents of the University of California. All rights reserved.\n"); 70 #endif /* not lint */ 71 72 #ifndef lint 73 #if 0 74 static char sccsid[] = "@(#)main.c 8.1 (Berkeley) 6/7/93"; 75 #else 76 __RCSID("$NetBSD: main.c,v 1.6 2003/08/07 09:28:00 agc Exp $"); 77 #endif 78 #endif /* not lint */ 79 80 /* 81 * Entry point, initialization, miscellaneous routines. 82 */ 83 84 #include <sys/types.h> 85 #include <sys/file.h> 86 #include <stdio.h> 87 #include <string.h> 88 #include <errno.h> 89 #include <stdlib.h> 90 #include <unistd.h> 91 92 #include "less.h" 93 #include "extern.h" 94 95 int ispipe; 96 int new_file; 97 int is_tty; 98 char *current_file, *previous_file, *current_name, *next_name; 99 off_t prev_pos; 100 int any_display; 101 int scroll; 102 int ac; 103 char **av; 104 int curr_ac; 105 int quitting; 106 107 static void cat_file __P((void)); 108 /* 109 * Edit a new file. 110 * Filename "-" means standard input. 111 * No filename means the "current" file, from the command line. 112 */ 113 int 114 edit(filename) 115 char *filename; 116 { 117 int f; 118 char *m; 119 off_t initial_pos; 120 static int didpipe; 121 char message[100], *p; 122 123 initial_pos = NULL_POSITION; 124 if (filename == NULL || *filename == '\0') { 125 if (curr_ac >= ac) { 126 error("No current file"); 127 return(0); 128 } 129 filename = save(av[curr_ac]); 130 } 131 else if (strcmp(filename, "#") == 0) { 132 if (*previous_file == '\0') { 133 error("no previous file"); 134 return(0); 135 } 136 filename = save(previous_file); 137 initial_pos = prev_pos; 138 } else 139 filename = save(filename); 140 141 /* use standard input. */ 142 if (!strcmp(filename, "-")) { 143 if (didpipe) { 144 error("Can view standard input only once"); 145 return(0); 146 } 147 f = 0; 148 } 149 else if ((m = bad_file(filename, message, sizeof(message))) != NULL) { 150 error(m); 151 free(filename); 152 return(0); 153 } 154 else if ((f = open(filename, O_RDONLY, 0)) < 0) { 155 (void)snprintf(message, sizeof(message), "%s: %s", filename, 156 strerror(errno)); 157 error(message); 158 free(filename); 159 return(0); 160 } 161 162 if (isatty(f)) { 163 /* 164 * Not really necessary to call this an error, 165 * but if the control terminal (for commands) 166 * and the input file (for data) are the same, 167 * we get weird results at best. 168 */ 169 error("Can't take input from a terminal"); 170 if (f > 0) 171 (void)close(f); 172 (void)free(filename); 173 return(0); 174 } 175 176 /* 177 * We are now committed to using the new file. 178 * Close the current input file and set up to use the new one. 179 */ 180 if (file > 0) 181 (void)close(file); 182 new_file = 1; 183 if (previous_file != NULL) 184 free(previous_file); 185 previous_file = current_file; 186 current_file = filename; 187 pos_clear(); 188 prev_pos = position(TOP); 189 ispipe = (f == 0); 190 if (ispipe) { 191 didpipe = 1; 192 current_name = "stdin"; 193 } else 194 current_name = (p = rindex(filename, '/')) ? p + 1 : filename; 195 if (curr_ac >= ac) 196 next_name = NULL; 197 else 198 next_name = av[curr_ac + 1]; 199 file = f; 200 ch_init(cbufs, 0); 201 init_mark(); 202 203 if (is_tty) { 204 int no_display = !any_display; 205 any_display = 1; 206 if (no_display && errmsgs > 0) { 207 /* 208 * We displayed some messages on error output 209 * (file descriptor 2; see error() function). 210 * Before erasing the screen contents, 211 * display the file name and wait for a keystroke. 212 */ 213 error(filename); 214 } 215 /* 216 * Indicate there is nothing displayed yet. 217 */ 218 if (initial_pos != NULL_POSITION) 219 jump_loc(initial_pos); 220 clr_linenum(); 221 } 222 return(1); 223 } 224 225 /* 226 * Edit the next file in the command line list. 227 */ 228 void 229 next_file(n) 230 int n; 231 { 232 if (curr_ac + n >= ac) { 233 if (quit_at_eof || position(TOP) == NULL_POSITION) 234 quit(); 235 error("No (N-th) next file"); 236 } 237 else 238 (void)edit(av[curr_ac += n]); 239 } 240 241 /* 242 * Edit the previous file in the command line list. 243 */ 244 void 245 prev_file(n) 246 int n; 247 { 248 if (curr_ac - n < 0) 249 error("No (N-th) previous file"); 250 else 251 (void)edit(av[curr_ac -= n]); 252 } 253 254 /* 255 * copy a file directly to standard output; used if stdout is not a tty. 256 * the only processing is to squeeze multiple blank input lines. 257 */ 258 static void 259 cat_file() 260 { 261 int c, empty; 262 263 if (squeeze) { 264 empty = 0; 265 while ((c = ch_forw_get()) != EOI) 266 if (c != '\n') { 267 putchr(c); 268 empty = 0; 269 } 270 else if (empty < 2) { 271 putchr(c); 272 ++empty; 273 } 274 } 275 else while ((c = ch_forw_get()) != EOI) 276 putchr(c); 277 flush(); 278 } 279 280 int 281 main(argc, argv) 282 int argc; 283 char **argv; 284 { 285 int envargc, argcnt; 286 char *envargv[2]; 287 288 /* 289 * Process command line arguments and MORE environment arguments. 290 * Command line arguments override environment arguments. 291 */ 292 if ((envargv[1] = getenv("MORE")) != NULL) { 293 envargc = 2; 294 envargv[0] = "more"; 295 envargv[2] = NULL; 296 (void)option(envargc, envargv); 297 } 298 argcnt = option(argc, argv); 299 argv += argcnt; 300 argc -= argcnt; 301 302 /* 303 * Set up list of files to be examined. 304 */ 305 ac = argc; 306 av = argv; 307 curr_ac = 0; 308 309 /* 310 * Set up terminal, etc. 311 */ 312 is_tty = isatty(1); 313 if (!is_tty) { 314 /* 315 * Output is not a tty. 316 * Just copy the input file(s) to output. 317 */ 318 if (ac < 1) { 319 (void)edit("-"); 320 cat_file(); 321 } else { 322 do { 323 (void)edit((char *)NULL); 324 if (file >= 0) 325 cat_file(); 326 } while (++curr_ac < ac); 327 } 328 exit(0); 329 } 330 331 raw_mode(1); 332 get_term(); 333 open_getchr(); 334 init(); 335 init_signals(1); 336 337 /* select the first file to examine. */ 338 if (ac < 1) 339 (void)edit("-"); /* Standard input */ 340 else { 341 /* 342 * Try all the files named as command arguments. 343 * We are simply looking for one which can be 344 * opened without error. 345 */ 346 do { 347 (void)edit((char *)NULL); 348 } while (file < 0 && ++curr_ac < ac); 349 } 350 351 if (file >= 0) 352 commands(); 353 quit(); 354 } 355 356 /* 357 * Copy a string to a "safe" place 358 * (that is, to a buffer allocated by malloc). 359 */ 360 char * 361 save(s) 362 char *s; 363 { 364 char *p; 365 366 p = strdup(s); 367 if (p == NULL) 368 { 369 error("cannot allocate memory"); 370 quit(); 371 } 372 return(p); 373 } 374 375 /* 376 * Exit the program. 377 */ 378 void 379 quit() 380 { 381 /* 382 * Put cursor at bottom left corner, clear the line, 383 * reset the terminal modes, and exit. 384 */ 385 quitting = 1; 386 lower_left(); 387 clear_eol(); 388 deinit(); 389 flush(); 390 raw_mode(0); 391 exit(0); 392 } 393
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