contrib/less/main.c

   1 /*
   2  * Copyright (C) 1984-2015  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      pr_type;
  60
  61
  62 /*
  63  * Entry point.
  64  */
  65 int
  66 main(argc, argv)
  67         int argc;
  68         char *argv[];
  69 {
  70         IFILE ifile;
  71         char *s;
  72
  73 #ifdef __EMX__
  74         _response(&argc, &argv);
  75         _wildcard(&argc, &argv);
  76 #endif
  77
  78         progname = *argv++;
  79         argc--;
  80
  81         secure = 0;
  82         s = lgetenv("LESSSECURE");
  83         if (s != NULL && *s != '\0')
  84                 secure = 1;
  85
  86 #ifdef WIN32
  87         if (getenv("HOME") == NULL)
  88         {
  89                 /*
  90                  * If there is no HOME environment variable,
  91                  * try the concatenation of HOMEDRIVE + HOMEPATH.
  92                  */
  93                 char *drive = getenv("HOMEDRIVE");
  94                 char *path  = getenv("HOMEPATH");
  95                 if (drive != NULL && path != NULL)
  96                 {
  97                         char *env = (char *) ecalloc(strlen(drive) +
  98                                         strlen(path) + 6, sizeof(char));
  99                         strcpy(env, "HOME=");
 100                         strcat(env, drive);
 101                         strcat(env, path);
 102                         putenv(env);
 103                 }
 104         }
 105         GetConsoleTitle(consoleTitle, sizeof(consoleTitle)/sizeof(char));
 106 #endif /* WIN32 */
 107
 108         /*
 109          * Process command line arguments and LESS environment arguments.
 110          * Command line arguments override environment arguments.
 111          */
 112         is_tty = isatty(1);
 113         get_term();
 114         init_cmds();
 115         init_charset();
 116         init_line();
 117         init_cmdhist();
 118         init_option();
 119         init_search();
 120
 121         /*
 122          * If the name of the executable program is "more",
 123          * act like LESS_IS_MORE is set.
 124          */
 125         for (s = progname + strlen(progname);  s > progname;  s--)
 126         {
 127                 if (s[-1] == PATHNAME_SEP[0])
 128                         break;
 129         }
 130         if (strcmp(s, "more") == 0)
 131                 less_is_more = 1;
 132
 133         init_prompt();
 134
 135         s = lgetenv(less_is_more ? "MORE" : "LESS");
 136         if (s != NULL)
 137                 scan_option(save(s));
 138
 139 #define isoptstring(s)  (((s)[0] == '-' || (s)[0] == '+') && (s)[1] != '\0')
 140         while (argc > 0 && (isoptstring(*argv) || isoptpending()))
 141         {
 142                 s = *argv++;
 143                 argc--;
 144                 if (strcmp(s, "--") == 0)
 145                         break;
 146                 scan_option(s);
 147         }
 148 #undef isoptstring
 149
 150         if (isoptpending())
 151         {
 152                 /*
 153                  * Last command line option was a flag requiring a
 154                  * following string, but there was no following string.
 155                  */
 156                 nopendopt();
 157                 quit(QUIT_OK);
 158         }
 159
 160 #if EDITOR
 161         editor = lgetenv("VISUAL");
 162         if (editor == NULL || *editor == '\0')
 163         {
 164                 editor = lgetenv("EDITOR");
 165                 if (editor == NULL || *editor == '\0')
 166                         editor = EDIT_PGM;
 167         }
 168         editproto = lgetenv("LESSEDIT");
 169         if (editproto == NULL || *editproto == '\0')
 170                 editproto = "%E ?lm+%lm. %f";
 171 #endif
 172
 173         /*
 174          * Call get_ifile with all the command line filenames
 175          * to "register" them with the ifile system.
 176          */
 177         ifile = NULL_IFILE;
 178         if (dohelp)
 179                 ifile = get_ifile(FAKE_HELPFILE, ifile);
 180         while (argc-- > 0)
 181         {
 182                 char *filename;
 183 #if (MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC)
 184                 /*
 185                  * Because the "shell" doesn't expand filename patterns,
 186                  * treat each argument as a filename pattern rather than
 187                  * a single filename.
 188                  * Expand the pattern and iterate over the expanded list.
 189                  */
 190                 struct textlist tlist;
 191                 char *gfilename;
 192
 193                 gfilename = lglob(*argv++);
 194                 init_textlist(&tlist, gfilename);
 195                 filename = NULL;
 196                 while ((filename = forw_textlist(&tlist, filename)) != NULL)
 197                 {
 198                         (void) get_ifile(filename, ifile);
 199                         ifile = prev_ifile(NULL_IFILE);
 200                 }
 201                 free(gfilename);
 202 #else
 203                 filename = shell_quote(*argv);
 204                 if (filename == NULL)
 205                         filename = *argv;
 206                 argv++;
 207                 (void) get_ifile(filename, ifile);
 208                 ifile = prev_ifile(NULL_IFILE);
 209                 free(filename);
 210 #endif
 211         }
 212         /*
 213          * Set up terminal, etc.
 214          */
 215         if (!is_tty)
 216         {
 217                 /*
 218                  * Output is not a tty.
 219                  * Just copy the input file(s) to output.
 220                  */
 221                 SET_BINARY(1);
 222                 if (nifile() == 0)
 223                 {
 224                         if (edit_stdin() == 0)
 225                                 cat_file();
 226                 } else if (edit_first() == 0)
 227                 {
 228                         do {
 229                                 cat_file();
 230                         } while (edit_next(1) == 0);
 231                 }
 232                 quit(QUIT_OK);
 233         }
 234
 235         if (missing_cap && !know_dumb)
 236                 error("WARNING: terminal is not fully functional", NULL_PARG);
 237         init_mark();
 238         open_getchr();
 239         raw_mode(1);
 240         init_signals(1);
 241
 242         /*
 243          * Select the first file to examine.
 244          */
 245 #if TAGS
 246         if (tagoption != NULL || strcmp(tags, "-") == 0)
 247         {
 248                 /*
 249                  * A -t option was given.
 250                  * Verify that no filenames were also given.
 251                  * Edit the file selected by the "tags" search,
 252                  * and search for the proper line in the file.
 253                  */
 254                 if (nifile() > 0)
 255                 {
 256                         error("No filenames allowed with -t option", NULL_PARG);
 257                         quit(QUIT_ERROR);
 258                 }
 259                 findtag(tagoption);
 260                 if (edit_tagfile())  /* Edit file which contains the tag */
 261                         quit(QUIT_ERROR);
 262                 /*
 263                  * Search for the line which contains the tag.
 264                  * Set up initial_scrpos so we display that line.
 265                  */
 266                 initial_scrpos.pos = tagsearch();
 267                 if (initial_scrpos.pos == NULL_POSITION)
 268                         quit(QUIT_ERROR);
 269                 initial_scrpos.ln = jump_sline;
 270         } else
 271 #endif
 272         if (nifile() == 0)
 273         {
 274                 if (edit_stdin())  /* Edit standard input */
 275                         quit(QUIT_ERROR);
 276         } else
 277         {
 278                 if (edit_first())  /* Edit first valid file in cmd line */
 279                         quit(QUIT_ERROR);
 280         }
 281
 282         init();
 283         commands();
 284         quit(QUIT_OK);
 285         /*NOTREACHED*/
 286         return (0);
 287 }
 288
 289 /*
 290  * Copy a string to a "safe" place
 291  * (that is, to a buffer allocated by calloc).
 292  */
 293         public char *
 294 save(s)
 295         char *s;
 296 {
 297         register char *p;
 298
 299         p = (char *) ecalloc(strlen(s)+1, sizeof(char));
 300         strcpy(p, s);
 301         return (p);
 302 }
 303
 304 /*
 305  * Allocate memory.
 306  * Like calloc(), but never returns an error (NULL).
 307  */
 308         public VOID_POINTER
 309 ecalloc(count, size)
 310         int count;
 311         unsigned int size;
 312 {
 313         register VOID_POINTER p;
 314
 315         p = (VOID_POINTER) calloc(count, size);
 316         if (p != NULL)
 317                 return (p);
 318         error("Cannot allocate memory", NULL_PARG);
 319         quit(QUIT_ERROR);
 320         /*NOTREACHED*/
 321         return (NULL);
 322 }
 323
 324 /*
 325  * Skip leading spaces in a string.
 326  */
 327         public char *
 328 skipsp(s)
 329         register char *s;
 330 {
 331         while (*s == ' ' || *s == '\t')
 332                 s++;
 333         return (s);
 334 }
 335
 336 /*
 337  * See how many characters of two strings are identical.
 338  * If uppercase is true, the first string must begin with an uppercase
 339  * character; the remainder of the first string may be either case.
 340  */
 341         public int
 342 sprefix(ps, s, uppercase)
 343         char *ps;
 344         char *s;
 345         int uppercase;
 346 {
 347         register int c;
 348         register int sc;
 349         register int len = 0;
 350
 351         for ( ;  *s != '\0';  s++, ps++)
 352         {
 353                 c = *ps;
 354                 if (uppercase)
 355                 {
 356                         if (len == 0 && ASCII_IS_LOWER(c))
 357                                 return (-1);
 358                         if (ASCII_IS_UPPER(c))
 359                                 c = ASCII_TO_LOWER(c);
 360                 }
 361                 sc = *s;
 362                 if (len > 0 && ASCII_IS_UPPER(sc))
 363                         sc = ASCII_TO_LOWER(sc);
 364                 if (c != sc)
 365                         break;
 366                 len++;
 367         }
 368         return (len);
 369 }
 370
 371 /*
 372  * Exit the program.
 373  */
 374         public void
 375 quit(status)
 376         int status;
 377 {
 378         static int save_status;
 379
 380         /*
 381          * Put cursor at bottom left corner, clear the line,
 382          * reset the terminal modes, and exit.
 383          */
 384         if (status < 0)
 385                 status = save_status;
 386         else
 387                 save_status = status;
 388         quitting = 1;
 389         edit((char*)NULL);
 390         save_cmdhist();
 391         if (any_display && is_tty)
 392                 clear_bot();
 393         deinit();
 394         flush();
 395         raw_mode(0);
 396 #if MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC
 397         /*
 398          * If we don't close 2, we get some garbage from
 399          * 2's buffer when it flushes automatically.
 400          * I cannot track this one down  RB
 401          * The same bug shows up if we use ^C^C to abort.
 402          */
 403         close(2);
 404 #endif
 405 #ifdef WIN32
 406         SetConsoleTitle(consoleTitle);
 407 #endif
 408         close_getchr();
 409         exit(status);
 410 }