| 1 | /* |
| 2 | * Copyright (c) 1988 Mark Nudleman |
| 3 | * Copyright (c) 1988 Regents of the University of California. |
| 4 | * All rights reserved. |
| 5 | * |
| 6 | * Redistribution and use in source and binary forms are permitted |
| 7 | * provided that the above copyright notice and this paragraph are |
| 8 | * duplicated in all such forms and that any documentation, |
| 9 | * advertising materials, and other materials related to such |
| 10 | * distribution and use acknowledge that the software was developed |
| 11 | * by Mark Nudleman and the University of California, Berkeley. The |
| 12 | * name of Mark Nudleman or the |
| 13 | * University may not be used to endorse or promote products derived |
| 14 | * from this software without specific prior written permission. |
| 15 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR |
| 16 | * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED |
| 17 | * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. |
| 18 | */ |
| 19 | |
| 20 | #ifndef lint |
| 21 | char copyright[] = |
| 22 | "@(#) Copyright (c) 1988 Mark Nudleman.\n\ |
| 23 | @(#) Copyright (c) 1988 Regents of the University of California.\n\ |
| 24 | All rights reserved.\n"; |
| 25 | #endif /* not lint */ |
| 26 | |
| 27 | #ifndef lint |
| 28 | static char sccsid[] = "@(#)main.c 5.7 (Berkeley) %G%"; |
| 29 | #endif /* not lint */ |
| 30 | |
| 31 | /* |
| 32 | * Entry point, initialization, miscellaneous routines. |
| 33 | */ |
| 34 | |
| 35 | #include "less.h" |
| 36 | #include "position.h" |
| 37 | |
| 38 | public int ispipe; |
| 39 | public char * first_cmd; |
| 40 | public char * every_first_cmd; |
| 41 | public int new_file; |
| 42 | public int is_tty; |
| 43 | public char *current_file; |
| 44 | public char *previous_file; |
| 45 | public POSITION prev_pos; |
| 46 | public int any_display; |
| 47 | public int scroll; |
| 48 | public int ac; |
| 49 | public char ** av; |
| 50 | public int curr_ac; |
| 51 | public int quitting; |
| 52 | |
| 53 | extern int file; |
| 54 | extern int quit_at_eof; |
| 55 | extern int cbufs; |
| 56 | extern int errmsgs; |
| 57 | |
| 58 | public char * editor; |
| 59 | |
| 60 | extern char * tagfile; |
| 61 | extern char * tagpattern; |
| 62 | extern int tagoption; |
| 63 | |
| 64 | /* |
| 65 | * Edit a new file. |
| 66 | * Filename "-" means standard input. |
| 67 | * No filename means the "current" file, from the command line. |
| 68 | */ |
| 69 | public void |
| 70 | edit(filename) |
| 71 | register char *filename; |
| 72 | { |
| 73 | register int f; |
| 74 | register char *m; |
| 75 | POSITION initial_pos; |
| 76 | char message[100]; |
| 77 | static int didpipe; |
| 78 | |
| 79 | initial_pos = NULL_POSITION; |
| 80 | if (filename == NULL || *filename == '\0') |
| 81 | { |
| 82 | if (curr_ac >= ac) |
| 83 | { |
| 84 | error("No current file"); |
| 85 | return; |
| 86 | } |
| 87 | filename = save(av[curr_ac]); |
| 88 | } else if (strcmp(filename, "#") == 0) |
| 89 | { |
| 90 | if (*previous_file == '\0') |
| 91 | { |
| 92 | error("no previous file"); |
| 93 | return; |
| 94 | } |
| 95 | filename = save(previous_file); |
| 96 | initial_pos = prev_pos; |
| 97 | } else |
| 98 | filename = save(filename); |
| 99 | |
| 100 | if (strcmp(filename, "-") == 0) |
| 101 | { |
| 102 | /* |
| 103 | * Use standard input. |
| 104 | */ |
| 105 | if (didpipe) |
| 106 | { |
| 107 | error("Can view standard input only once"); |
| 108 | return; |
| 109 | } |
| 110 | f = 0; |
| 111 | } else if ((m = bad_file(filename, message, sizeof(message))) != NULL) |
| 112 | { |
| 113 | error(m); |
| 114 | free(filename); |
| 115 | return; |
| 116 | } else if ((f = open(filename, 0)) < 0) |
| 117 | { |
| 118 | error(errno_message(filename, message, sizeof(message))); |
| 119 | free(filename); |
| 120 | return; |
| 121 | } |
| 122 | |
| 123 | if (isatty(f)) |
| 124 | { |
| 125 | /* |
| 126 | * Not really necessary to call this an error, |
| 127 | * but if the control terminal (for commands) |
| 128 | * and the input file (for data) are the same, |
| 129 | * we get weird results at best. |
| 130 | */ |
| 131 | error("Can't take input from a terminal"); |
| 132 | if (f > 0) |
| 133 | close(f); |
| 134 | free(filename); |
| 135 | return; |
| 136 | } |
| 137 | |
| 138 | /* |
| 139 | * We are now committed to using the new file. |
| 140 | * Close the current input file and set up to use the new one. |
| 141 | */ |
| 142 | if (file > 0) |
| 143 | close(file); |
| 144 | new_file = 1; |
| 145 | if (previous_file != NULL) |
| 146 | free(previous_file); |
| 147 | previous_file = current_file; |
| 148 | current_file = filename; |
| 149 | prev_pos = position(TOP); |
| 150 | ispipe = (f == 0); |
| 151 | if (ispipe) |
| 152 | didpipe = 1; |
| 153 | file = f; |
| 154 | ch_init(cbufs, 0); |
| 155 | init_mark(); |
| 156 | |
| 157 | if (every_first_cmd != NULL) |
| 158 | first_cmd = every_first_cmd; |
| 159 | |
| 160 | if (is_tty) |
| 161 | { |
| 162 | int no_display = !any_display; |
| 163 | any_display = 1; |
| 164 | if (no_display && errmsgs > 0) |
| 165 | { |
| 166 | /* |
| 167 | * We displayed some messages on error output |
| 168 | * (file descriptor 2; see error() function). |
| 169 | * Before erasing the screen contents, |
| 170 | * display the file name and wait for a keystroke. |
| 171 | */ |
| 172 | error(filename); |
| 173 | } |
| 174 | /* |
| 175 | * Indicate there is nothing displayed yet. |
| 176 | */ |
| 177 | pos_clear(); |
| 178 | if (initial_pos != NULL_POSITION) |
| 179 | jump_loc(initial_pos); |
| 180 | clr_linenum(); |
| 181 | } |
| 182 | } |
| 183 | |
| 184 | /* |
| 185 | * Edit the next file in the command line list. |
| 186 | */ |
| 187 | public void |
| 188 | next_file(n) |
| 189 | int n; |
| 190 | { |
| 191 | if (curr_ac + n >= ac) |
| 192 | { |
| 193 | if (quit_at_eof) |
| 194 | quit(); |
| 195 | error("No (N-th) next file"); |
| 196 | } else |
| 197 | edit(av[curr_ac += n]); |
| 198 | } |
| 199 | |
| 200 | /* |
| 201 | * Edit the previous file in the command line list. |
| 202 | */ |
| 203 | public void |
| 204 | prev_file(n) |
| 205 | int n; |
| 206 | { |
| 207 | if (curr_ac - n < 0) |
| 208 | error("No (N-th) previous file"); |
| 209 | else |
| 210 | edit(av[curr_ac -= n]); |
| 211 | } |
| 212 | |
| 213 | /* |
| 214 | * Copy a file directly to standard output. |
| 215 | * Used if standard output is not a tty. |
| 216 | */ |
| 217 | static void |
| 218 | cat_file() |
| 219 | { |
| 220 | register int c; |
| 221 | |
| 222 | while ((c = ch_forw_get()) != EOI) |
| 223 | putchr(c); |
| 224 | flush(); |
| 225 | } |
| 226 | |
| 227 | /* |
| 228 | * Entry point. |
| 229 | */ |
| 230 | main(argc, argv) |
| 231 | int argc; |
| 232 | char *argv[]; |
| 233 | { |
| 234 | char *getenv(); |
| 235 | |
| 236 | |
| 237 | /* |
| 238 | * Process command line arguments and LESS environment arguments. |
| 239 | * Command line arguments override environment arguments. |
| 240 | */ |
| 241 | init_prompt(); |
| 242 | init_option(); |
| 243 | scan_option(getenv("LESS")); |
| 244 | argv++; |
| 245 | while ( (--argc > 0) && |
| 246 | (argv[0][0] == '-' || argv[0][0] == '+') && |
| 247 | argv[0][1] != '\0') |
| 248 | scan_option(*argv++); |
| 249 | |
| 250 | editor = getenv("EDITOR"); |
| 251 | if (editor == NULL || *editor == '\0') |
| 252 | editor = EDIT_PGM; |
| 253 | |
| 254 | /* |
| 255 | * Set up list of files to be examined. |
| 256 | */ |
| 257 | ac = argc; |
| 258 | av = argv; |
| 259 | curr_ac = 0; |
| 260 | |
| 261 | /* |
| 262 | * Set up terminal, etc. |
| 263 | */ |
| 264 | is_tty = isatty(1); |
| 265 | if (!is_tty) |
| 266 | { |
| 267 | /* |
| 268 | * Output is not a tty. |
| 269 | * Just copy the input file(s) to output. |
| 270 | */ |
| 271 | if (ac < 1) |
| 272 | { |
| 273 | edit("-"); |
| 274 | cat_file(); |
| 275 | } else |
| 276 | { |
| 277 | do |
| 278 | { |
| 279 | edit((char *)NULL); |
| 280 | if (file >= 0) |
| 281 | cat_file(); |
| 282 | } while (++curr_ac < ac); |
| 283 | } |
| 284 | exit(0); |
| 285 | } |
| 286 | |
| 287 | raw_mode(1); |
| 288 | get_term(); |
| 289 | open_getchr(); |
| 290 | init(); |
| 291 | init_cmd(); |
| 292 | |
| 293 | init_signals(1); |
| 294 | |
| 295 | /* |
| 296 | * Select the first file to examine. |
| 297 | */ |
| 298 | if (tagoption) |
| 299 | { |
| 300 | /* |
| 301 | * A -t option was given. |
| 302 | * Verify that no filenames were also given. |
| 303 | * Edit the file selected by the "tags" search, |
| 304 | * and search for the proper line in the file. |
| 305 | */ |
| 306 | if (ac > 0) |
| 307 | { |
| 308 | error("No filenames allowed with -t option"); |
| 309 | quit(); |
| 310 | } |
| 311 | if (tagfile == NULL) |
| 312 | quit(); |
| 313 | edit(tagfile); |
| 314 | if (file < 0) |
| 315 | quit(); |
| 316 | if (tagsearch()) |
| 317 | quit(); |
| 318 | } else |
| 319 | if (ac < 1) |
| 320 | edit("-"); /* Standard input */ |
| 321 | else |
| 322 | { |
| 323 | /* |
| 324 | * Try all the files named as command arguments. |
| 325 | * We are simply looking for one which can be |
| 326 | * opened without error. |
| 327 | */ |
| 328 | do |
| 329 | { |
| 330 | edit((char *)NULL); |
| 331 | } while (file < 0 && ++curr_ac < ac); |
| 332 | } |
| 333 | |
| 334 | if (file >= 0) |
| 335 | commands(); |
| 336 | quit(); |
| 337 | /*NOTREACHED*/ |
| 338 | } |
| 339 | |
| 340 | /* |
| 341 | * Copy a string, truncating to the specified length if necessary. |
| 342 | * Unlike strncpy(), the resulting string is guaranteed to be null-terminated. |
| 343 | */ |
| 344 | public void |
| 345 | strtcpy(to, from, len) |
| 346 | char *to; |
| 347 | char *from; |
| 348 | unsigned int len; |
| 349 | { |
| 350 | strncpy(to, from, len); |
| 351 | to[len-1] = '\0'; |
| 352 | } |
| 353 | |
| 354 | /* |
| 355 | * Copy a string to a "safe" place |
| 356 | * (that is, to a buffer allocated by malloc). |
| 357 | */ |
| 358 | public char * |
| 359 | save(s) |
| 360 | char *s; |
| 361 | { |
| 362 | char *p, *strcpy(), *malloc(); |
| 363 | |
| 364 | p = malloc((u_int)strlen(s)+1); |
| 365 | if (p == NULL) |
| 366 | { |
| 367 | error("cannot allocate memory"); |
| 368 | quit(); |
| 369 | } |
| 370 | return(strcpy(p, s)); |
| 371 | } |
| 372 | |
| 373 | /* |
| 374 | * Exit the program. |
| 375 | */ |
| 376 | public void |
| 377 | quit() |
| 378 | { |
| 379 | /* |
| 380 | * Put cursor at bottom left corner, clear the line, |
| 381 | * reset the terminal modes, and exit. |
| 382 | */ |
| 383 | quitting = 1; |
| 384 | lower_left(); |
| 385 | clear_eol(); |
| 386 | deinit(); |
| 387 | flush(); |
| 388 | raw_mode(0); |
| 389 | exit(0); |
| 390 | } |