bin/less/main.c

   1 /*
   2  * Copyright (C) 1984-2012  Mark Nudelman
   3  * Modified for use with illumos by Garrett D'Amore.
   4  * Copyright 2014 Garrett D'Amore <garrett@damore.org>
   5  *
   6  * You may distribute under the terms of either the GNU General Public
   7  * License or the Less License, as specified in the README file.
   8  *
   9  * For more information, see the README file.
  10  */
  11
  12 /*
  13  * Entry point, initialization, miscellaneous routines.
  14  */
  15
  16 #include <sys/types.h>
  17
  18 #include <libgen.h>
  19 #include <stdarg.h>
  20
  21 #include "less.h"
  22
  23 char    *every_first_cmd = NULL;
  24 int     new_file;
  25 int     is_tty;
  26 IFILE   curr_ifile = NULL;
  27 IFILE   old_ifile = NULL;
  28 struct scrpos initial_scrpos;
  29 int     any_display = FALSE;
  30 off_t   start_attnpos = -1;
  31 off_t   end_attnpos = -1;
  32 int     wscroll;
  33
  34 static char     *progname;
  35
  36 int     quitting;
  37 int     secure;
  38 int     dohelp;
  39
  40 int logfile = -1;
  41 int force_logfile = FALSE;
  42 char *namelogfile = NULL;
  43 char *editor;
  44 char *editproto;
  45
  46 extern char     *tags;
  47 extern char     *tagoption;
  48 extern int      jump_sline;
  49 extern int      less_is_more;
  50 extern int      missing_cap;
  51 extern int      know_dumb;
  52 extern int      quit_if_one_screen;
  53 extern int      quit_at_eof;
  54 extern int      pr_type;
  55 extern int      hilite_search;
  56 extern int      use_lessopen;
  57 extern int      no_init;
  58 extern int      top_scroll;
  59 extern int      errmsgs;
  60
  61
  62 /*
  63  * Entry point.
  64  */
  65 int
  66 main(int argc, char *argv[])
  67 {
  68         IFILE ifile;
  69         char *s;
  70
  71         progname = basename(argv[0]);
  72         argv++;
  73         argc--;
  74
  75         /*
  76          * If the name of the executable program is "more",
  77          * act like LESS_IS_MORE is set.  We have to set this as early
  78          * as possible for POSIX.
  79          */
  80         if (strcmp(progname, "more") == 0)
  81                 less_is_more = 1;
  82         else {
  83                 s = lgetenv("LESS_IS_MORE");
  84                 if (s != NULL && *s != '\0')
  85                         less_is_more = 1;
  86         }
  87
  88         secure = 0;
  89         s = lgetenv("LESSSECURE");
  90         if (s != NULL && *s != '\0')
  91                 secure = 1;
  92
  93         if (secure) {
  94                 if (pledge("stdio rpath wpath tty", NULL) == -1) {
  95                         perror("pledge");
  96                         exit(1);
  97                 }
  98         } else {
  99                 if (pledge("stdio rpath wpath cpath fattr proc exec tty", NULL) == -1) {
 100                         perror("pledge");
 101                         exit(1);
 102                 }
 103         }
 104
 105         /*
 106          * Process command line arguments and LESS environment arguments.
 107          * Command line arguments override environment arguments.
 108          */
 109         is_tty = isatty(1);
 110         get_term();
 111         init_cmds();
 112         init_charset();
 113         init_line();
 114         init_cmdhist();
 115         init_option();
 116         init_search();
 117
 118
 119         init_prompt();
 120
 121         if (less_is_more) {
 122                 /* this is specified by XPG */
 123                 quit_at_eof = OPT_ON;
 124
 125                 /* more users don't like the warning */
 126                 know_dumb = OPT_ON;
 127
 128                 /* default prompt is medium */
 129                 pr_type = OPT_ON;
 130
 131                 /* do not hilight search terms */
 132                 hilite_search = OPT_OFF;
 133
 134                 /* do not use LESSOPEN */
 135                 use_lessopen = OPT_OFF;
 136
 137                 /* do not set init strings to terminal */
 138                 no_init = OPT_ON;
 139
 140                 /* repaint from top of screen */
 141                 top_scroll = OPT_OFF;
 142         }
 143
 144         s = lgetenv(less_is_more ? "MORE" : "LESS");
 145         if (s != NULL)
 146                 scan_option(estrdup(s));
 147
 148 #define isoptstring(s)  (((s)[0] == '-' || (s)[0] == '+') && (s)[1] != '\0')
 149         while (argc > 0 && (isoptstring(*argv) || isoptpending())) {
 150                 s = *argv++;
 151                 argc--;
 152                 if (strcmp(s, "--") == 0)
 153                         break;
 154                 scan_option(s);
 155         }
 156 #undef isoptstring
 157
 158         if (isoptpending()) {
 159                 /*
 160                  * Last command line option was a flag requiring a
 161                  * following string, but there was no following string.
 162                  */
 163                 nopendopt();
 164                 quit(QUIT_OK);
 165         }
 166
 167         if (errmsgs) {
 168                 quit(QUIT_ERROR);
 169         }
 170         if (less_is_more && quit_at_eof == OPT_ONPLUS) {
 171                 extern int no_init;
 172                 no_init = OPT_ON;
 173         }
 174         if (less_is_more && pr_type == OPT_ONPLUS) {
 175                 extern int quiet;
 176                 quiet = VERY_QUIET;
 177         }
 178
 179         editor = lgetenv("VISUAL");
 180         if (editor == NULL || *editor == '\0') {
 181                 editor = lgetenv("EDITOR");
 182                 if (editor == NULL || *editor == '\0')
 183                         editor = EDIT_PGM;
 184         }
 185         editproto = lgetenv("LESSEDIT");
 186         if (editproto == NULL || *editproto == '\0')
 187                 editproto = "%E ?lm+%lm. %f";
 188
 189         /*
 190          * Call get_ifile with all the command line filenames
 191          * to "register" them with the ifile system.
 192          */
 193         ifile = NULL;
 194         if (dohelp)
 195                 ifile = get_ifile(helpfile(), ifile);
 196         while (argc-- > 0) {
 197                 char *filename;
 198                 filename = shell_quote(*argv);
 199                 if (filename == NULL)
 200                         filename = *argv;
 201                 argv++;
 202                 (void) get_ifile(filename, ifile);
 203                 ifile = prev_ifile(NULL);
 204                 free(filename);
 205         }
 206         /*
 207          * Set up terminal, etc.
 208          */
 209         if (!is_tty) {
 210                 /*
 211                  * Output is not a tty.
 212                  * Just copy the input file(s) to output.
 213                  */
 214                 if (nifile() == 0) {
 215                         if (edit_stdin() == 0)
 216                                 cat_file();
 217                 } else if (edit_first() == 0) {
 218                         do {
 219                                 cat_file();
 220                         } while (edit_next(1) == 0);
 221                 }
 222                 quit(QUIT_OK);
 223         }
 224
 225         if (missing_cap && !know_dumb)
 226                 error("WARNING: terminal is not fully functional", NULL);
 227         init_mark();
 228         open_getchr();
 229
 230         if (secure)
 231                 if (pledge("stdio rpath tty", NULL) == -1) {
 232                         perror("pledge");
 233                         exit(1);
 234                 }
 235
 236         raw_mode(1);
 237         init_signals(1);
 238
 239         /*
 240          * Select the first file to examine.
 241          */
 242         if (tagoption != NULL || strcmp(tags, "-") == 0) {
 243                 /*
 244                  * A -t option was given.
 245                  * Verify that no filenames were also given.
 246                  * Edit the file selected by the "tags" search,
 247                  * and search for the proper line in the file.
 248                  */
 249                 if (nifile() > 0) {
 250                         error("No filenames allowed with -t option", NULL);
 251                         quit(QUIT_ERROR);
 252                 }
 253                 findtag(tagoption);
 254                 if (edit_tagfile())  /* Edit file which contains the tag */
 255                         quit(QUIT_ERROR);
 256                 /*
 257                  * Search for the line which contains the tag.
 258                  * Set up initial_scrpos so we display that line.
 259                  */
 260                 initial_scrpos.pos = tagsearch();
 261                 if (initial_scrpos.pos == -1)
 262                         quit(QUIT_ERROR);
 263                 initial_scrpos.ln = jump_sline;
 264         } else if (nifile() == 0) {
 265                 if (edit_stdin())  /* Edit standard input */
 266                         quit(QUIT_ERROR);
 267         } else {
 268                 if (edit_first())  /* Edit first valid file in cmd line */
 269                         quit(QUIT_ERROR);
 270         }
 271
 272         init();
 273         commands();
 274         quit(QUIT_OK);
 275         return (0);
 276 }
 277
 278 /*
 279  * Allocate memory.
 280  * Like calloc(), but never returns an error (NULL).
 281  */
 282 void *
 283 ecalloc(int count, unsigned int size)
 284 {
 285         void *p;
 286
 287         p = calloc(count, size);
 288         if (p != NULL)
 289                 return (p);
 290         error("Cannot allocate memory", NULL);
 291         quit(QUIT_ERROR);
 292         return (NULL);
 293 }
 294
 295 char *
 296 easprintf(const char *fmt, ...)
 297 {
 298         char *p = NULL;
 299         int rv;
 300         va_list ap;
 301
 302         va_start(ap, fmt);
 303         rv = vasprintf(&p, fmt, ap);
 304         va_end(ap);
 305
 306         if (p == NULL || rv < 0) {
 307                 error("Cannot allocate memory", NULL);
 308                 quit(QUIT_ERROR);
 309         }
 310         return (p);
 311 }
 312
 313 char *
 314 estrdup(const char *str)
 315 {
 316         char *n;
 317
 318         n = strdup(str);
 319         if (n == NULL) {
 320                 error("Cannot allocate memory", NULL);
 321                 quit(QUIT_ERROR);
 322         }
 323         return (n);
 324 }
 325
 326 /*
 327  * Skip leading spaces in a string.
 328  */
 329 char *
 330 skipsp(char *s)
 331 {
 332         while (*s == ' ' || *s == '\t')
 333                 s++;
 334         return (s);
 335 }
 336
 337 /*
 338  * See how many characters of two strings are identical.
 339  * If uppercase is true, the first string must begin with an uppercase
 340  * character; the remainder of the first string may be either case.
 341  */
 342 int
 343 sprefix(char *ps, char *s, int uppercase)
 344 {
 345         int c;
 346         int sc;
 347         int len = 0;
 348
 349         for (; *s != '\0'; s++, ps++) {
 350                 c = *ps;
 351                 if (uppercase) {
 352                         if (len == 0 && islower(c))
 353                                 return (-1);
 354                         c = tolower(c);
 355                 }
 356                 sc = *s;
 357                 if (len > 0)
 358                         sc = tolower(sc);
 359                 if (c != sc)
 360                         break;
 361                 len++;
 362         }
 363         return (len);
 364 }
 365
 366 /*
 367  * Exit the program.
 368  */
 369 void
 370 quit(int status)
 371 {
 372         static int save_status;
 373
 374         /*
 375          * Put cursor at bottom left corner, clear the line,
 376          * reset the terminal modes, and exit.
 377          */
 378         if (status < 0)
 379                 status = save_status;
 380         else
 381                 save_status = status;
 382         quitting = 1;
 383         edit(NULL);
 384         if (!secure)
 385                 save_cmdhist();
 386         if (any_display && is_tty)
 387                 clear_bot();
 388         deinit();
 389         flush(1);
 390         raw_mode(0);
 391         exit(status);
 392 }
 393
 394 char *
 395 helpfile(void)
 396 {
 397         return (less_is_more ? HELPDIR "/more.help" : HELPDIR "/less.help");
 398 }