contrib/less/main.c

   1 /*
   2  * Copyright (C) 1984-2012  Mark Nudelman
   3  *
   4  * You may distribute under the terms of either the GNU General Public
   5  * License or the Less License, as specified in the README file.
   6  *
   7  * For more information, see the README file.
   8  */
   9
  10
  11 /*
  12  * Entry point, initialization, miscellaneous routines.
  13  */
  14
  15 #include "less.h"
  16 #if MSDOS_COMPILER==WIN32C
  17 #include <windows.h>
  18 #endif
  19
  20 public char *   every_first_cmd = NULL;
  21 public int      new_file;
  22 public int      is_tty;
  23 public IFILE    curr_ifile = NULL_IFILE;
  24 public IFILE    old_ifile = NULL_IFILE;
  25 public struct scrpos initial_scrpos;
  26 public int      any_display = FALSE;
  27 public POSITION start_attnpos = NULL_POSITION;
  28 public POSITION end_attnpos = NULL_POSITION;
  29 public int      wscroll;
  30 public char *   progname;
  31 public int      quitting;
  32 public int      secure;
  33 public int      dohelp;
  34
  35 #if LOGFILE
  36 public int      logfile = -1;
  37 public int      force_logfile = FALSE;
  38 public char *   namelogfile = NULL;
  39 #endif
  40
  41 #if EDITOR
  42 public char *   editor;
  43 public char *   editproto;
  44 #endif
  45
  46 #if TAGS
  47 extern char *   tags;
  48 extern char *   tagoption;
  49 extern int      jump_sline;
  50 #endif
  51
  52 #ifdef WIN32
  53 static char consoleTitle[256];
  54 #endif
  55
  56 extern int      less_is_more;
  57 extern int      missing_cap;
  58 extern int      know_dumb;
  59 extern int      quit_if_one_screen;
  60 extern int      pr_type;
  61
  62
  63 /*
  64  * Entry point.
  65  */
  66 int
  67 main(argc, argv)
  68         int argc;
  69         char *argv[];
  70 {
  71         IFILE ifile;
  72         char *s;
  73
  74 #ifdef __EMX__
  75         _response(&argc, &argv);
  76         _wildcard(&argc, &argv);
  77 #endif
  78
  79         progname = *argv++;
  80         argc--;
  81
  82         secure = 0;
  83         s = lgetenv("LESSSECURE");
  84         if (s != NULL && *s != '\0')
  85                 secure = 1;
  86
  87 #ifdef WIN32
  88         if (getenv("HOME") == NULL)
  89         {
  90                 /*
  91                  * If there is no HOME environment variable,
  92                  * try the concatenation of HOMEDRIVE + HOMEPATH.
  93                  */
  94                 char *drive = getenv("HOMEDRIVE");
  95                 char *path  = getenv("HOMEPATH");
  96                 if (drive != NULL && path != NULL)
  97                 {
  98                         char *env = (char *) ecalloc(strlen(drive) +
  99                                         strlen(path) + 6, sizeof(char));
 100                         strcpy(env, "HOME=");
 101                         strcat(env, drive);
 102                         strcat(env, path);
 103                         putenv(env);
 104                 }
 105         }
 106         GetConsoleTitle(consoleTitle, sizeof(consoleTitle)/sizeof(char));
 107 #endif /* WIN32 */
 108
 109         /*
 110          * Process command line arguments and LESS environment arguments.
 111          * Command line arguments override environment arguments.
 112          */
 113         is_tty = isatty(1);
 114         get_term();
 115         init_cmds();
 116         init_charset();
 117         init_line();
 118         init_cmdhist();
 119         init_option();
 120         init_search();
 121
 122         /*
 123          * If the name of the executable program is "more",
 124          * act like LESS_IS_MORE is set.
 125          */
 126         for (s = progname + strlen(progname);  s > progname;  s--)
 127         {
 128                 if (s[-1] == PATHNAME_SEP[0])
 129                         break;
 130         }
 131         if (strcmp(s, "more") == 0)
 132                 less_is_more = 1;
 133
 134         init_prompt();
 135
 136         s = lgetenv(less_is_more ? "MORE" : "LESS");
 137         if (s != NULL)
 138                 scan_option(save(s));
 139
 140 #define isoptstring(s)  (((s)[0] == '-' || (s)[0] == '+') && (s)[1] != '\0')
 141         while (argc > 0 && (isoptstring(*argv) || isoptpending()))
 142         {
 143                 s = *argv++;
 144                 argc--;
 145                 if (strcmp(s, "--") == 0)
 146                         break;
 147                 scan_option(s);
 148         }
 149 #undef isoptstring
 150
 151         if (isoptpending())
 152         {
 153                 /*
 154                  * Last command line option was a flag requiring a
 155                  * following string, but there was no following string.
 156                  */
 157                 nopendopt();
 158                 quit(QUIT_OK);
 159         }
 160
 161         if (less_is_more && get_quit_at_eof())
 162                 quit_if_one_screen = TRUE;
 163
 164 #if EDITOR
 165         editor = lgetenv("VISUAL");
 166         if (editor == NULL || *editor == '\0')
 167         {
 168                 editor = lgetenv("EDITOR");
 169                 if (editor == NULL || *editor == '\0')
 170                         editor = EDIT_PGM;
 171         }
 172         editproto = lgetenv("LESSEDIT");
 173         if (editproto == NULL || *editproto == '\0')
 174                 editproto = "%E ?lm+%lm. %f";
 175 #endif
 176
 177         /*
 178          * Call get_ifile with all the command line filenames
 179          * to "register" them with the ifile system.
 180          */
 181         ifile = NULL_IFILE;
 182         if (dohelp)
 183                 ifile = get_ifile(FAKE_HELPFILE, ifile);
 184         while (argc-- > 0)
 185         {
 186                 char *filename;
 187 #if (MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC)
 188                 /*
 189                  * Because the "shell" doesn't expand filename patterns,
 190                  * treat each argument as a filename pattern rather than
 191                  * a single filename.
 192                  * Expand the pattern and iterate over the expanded list.
 193                  */
 194                 struct textlist tlist;
 195                 char *gfilename;
 196
 197                 gfilename = lglob(*argv++);
 198                 init_textlist(&tlist, gfilename);
 199                 filename = NULL;
 200                 while ((filename = forw_textlist(&tlist, filename)) != NULL)
 201                 {
 202                         (void) get_ifile(filename, ifile);
 203                         ifile = prev_ifile(NULL_IFILE);
 204                 }
 205                 free(gfilename);
 206 #else
 207                 filename = shell_quote(*argv);
 208                 if (filename == NULL)
 209                         filename = *argv;
 210                 argv++;
 211                 (void) get_ifile(filename, ifile);
 212                 ifile = prev_ifile(NULL_IFILE);
 213                 free(filename);
 214 #endif
 215         }
 216         /*
 217          * Set up terminal, etc.
 218          */
 219         if (!is_tty)
 220         {
 221                 /*
 222                  * Output is not a tty.
 223                  * Just copy the input file(s) to output.
 224                  */
 225                 SET_BINARY(1);
 226                 if (nifile() == 0)
 227                 {
 228                         if (edit_stdin() == 0)
 229                                 cat_file();
 230                 } else if (edit_first() == 0)
 231                 {
 232                         do {
 233                                 cat_file();
 234                         } while (edit_next(1) == 0);
 235                 }
 236                 quit(QUIT_OK);
 237         }
 238
 239         if (missing_cap && !know_dumb)
 240                 error("WARNING: terminal is not fully functional", NULL_PARG);
 241         init_mark();
 242         open_getchr();
 243         raw_mode(1);
 244         init_signals(1);
 245
 246         /*
 247          * Select the first file to examine.
 248          */
 249 #if TAGS
 250         if (tagoption != NULL || strcmp(tags, "-") == 0)
 251         {
 252                 /*
 253                  * A -t option was given.
 254                  * Verify that no filenames were also given.
 255                  * Edit the file selected by the "tags" search,
 256                  * and search for the proper line in the file.
 257                  */
 258                 if (nifile() > 0)
 259                 {
 260                         error("No filenames allowed with -t option", NULL_PARG);
 261                         quit(QUIT_ERROR);
 262                 }
 263                 findtag(tagoption);
 264                 if (edit_tagfile())  /* Edit file which contains the tag */
 265                         quit(QUIT_ERROR);
 266                 /*
 267                  * Search for the line which contains the tag.
 268                  * Set up initial_scrpos so we display that line.
 269                  */
 270                 initial_scrpos.pos = tagsearch();
 271                 if (initial_scrpos.pos == NULL_POSITION)
 272                         quit(QUIT_ERROR);
 273                 initial_scrpos.ln = jump_sline;
 274         } else
 275 #endif
 276         if (nifile() == 0)
 277         {
 278                 if (edit_stdin())  /* Edit standard input */
 279                         quit(QUIT_ERROR);
 280         } else
 281         {
 282                 if (edit_first())  /* Edit first valid file in cmd line */
 283                         quit(QUIT_ERROR);
 284         }
 285
 286         init();
 287         commands();
 288         quit(QUIT_OK);
 289         /*NOTREACHED*/
 290         return (0);
 291 }
 292
 293 /*
 294  * Copy a string to a "safe" place
 295  * (that is, to a buffer allocated by calloc).
 296  */
 297         public char *
 298 save(s)
 299         char *s;
 300 {
 301         register char *p;
 302
 303         p = (char *) ecalloc(strlen(s)+1, sizeof(char));
 304         strcpy(p, s);
 305         return (p);
 306 }
 307
 308 /*
 309  * Allocate memory.
 310  * Like calloc(), but never returns an error (NULL).
 311  */
 312         public VOID_POINTER
 313 ecalloc(count, size)
 314         int count;
 315         unsigned int size;
 316 {
 317         register VOID_POINTER p;
 318
 319         p = (VOID_POINTER) calloc(count, size);
 320         if (p != NULL)
 321                 return (p);
 322         error("Cannot allocate memory", NULL_PARG);
 323         quit(QUIT_ERROR);
 324         /*NOTREACHED*/
 325         return (NULL);
 326 }
 327
 328 /*
 329  * Skip leading spaces in a string.
 330  */
 331         public char *
 332 skipsp(s)
 333         register char *s;
 334 {
 335         while (*s == ' ' || *s == '\t')
 336                 s++;
 337         return (s);
 338 }
 339
 340 /*
 341  * See how many characters of two strings are identical.
 342  * If uppercase is true, the first string must begin with an uppercase
 343  * character; the remainder of the first string may be either case.
 344  */
 345         public int
 346 sprefix(ps, s, uppercase)
 347         char *ps;
 348         char *s;
 349         int uppercase;
 350 {
 351         register int c;
 352         register int sc;
 353         register int len = 0;
 354
 355         for ( ;  *s != '\0';  s++, ps++)
 356         {
 357                 c = *ps;
 358                 if (uppercase)
 359                 {
 360                         if (len == 0 && ASCII_IS_LOWER(c))
 361                                 return (-1);
 362                         if (ASCII_IS_UPPER(c))
 363                                 c = ASCII_TO_LOWER(c);
 364                 }
 365                 sc = *s;
 366                 if (len > 0 && ASCII_IS_UPPER(sc))
 367                         sc = ASCII_TO_LOWER(sc);
 368                 if (c != sc)
 369                         break;
 370                 len++;
 371         }
 372         return (len);
 373 }
 374
 375 /*
 376  * Exit the program.
 377  */
 378         public void
 379 quit(status)
 380         int status;
 381 {
 382         static int save_status;
 383
 384         /*
 385          * Put cursor at bottom left corner, clear the line,
 386          * reset the terminal modes, and exit.
 387          */
 388         if (status < 0)
 389                 status = save_status;
 390         else
 391                 save_status = status;
 392         quitting = 1;
 393         edit((char*)NULL);
 394         save_cmdhist();
 395         if (any_display && is_tty)
 396                 clear_bot();
 397         deinit();
 398         flush();
 399         raw_mode(0);
 400 #if MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC
 401         /*
 402          * If we don't close 2, we get some garbage from
 403          * 2's buffer when it flushes automatically.
 404          * I cannot track this one down  RB
 405          * The same bug shows up if we use ^C^C to abort.
 406          */
 407         close(2);
 408 #endif
 409 #ifdef WIN32
 410         SetConsoleTitle(consoleTitle);
 411 #endif
 412         close_getchr();
 413         exit(status);
 414 }