external/bsd/less/dist/lsystem.c

   1 /*      $NetBSD: lsystem.c,v 1.4 2013/09/04 19:44:21 tron Exp $ */
   2
   3 /*
   4  * Copyright (C) 1984-2012  Mark Nudelman
   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 /*
  14  * Routines to execute other programs.
  15  * Necessarily very OS dependent.
  16  */
  17
  18 #include "less.h"
  19 #include <signal.h>
  20 #include "position.h"
  21
  22 #if MSDOS_COMPILER
  23 #include <dos.h>
  24 #ifdef _MSC_VER
  25 #include <direct.h>
  26 #define setdisk(n) _chdrive((n)+1)
  27 #else
  28 #include <dir.h>
  29 #endif
  30 #endif
  31
  32 extern int screen_trashed;
  33 extern IFILE curr_ifile;
  34
  35
  36 #if HAVE_SYSTEM
  37
  38 /*
  39  * Pass the specified command to a shell to be executed.
  40  * Like plain "system()", but handles resetting terminal modes, etc.
  41  */
  42         public void
  43 lsystem(cmd, donemsg)
  44         char *cmd;
  45         char *donemsg;
  46 {
  47         register int inp;
  48 #if HAVE_SHELL
  49         register char *shell;
  50         register char *p;
  51 #endif
  52         IFILE save_ifile;
  53 #if MSDOS_COMPILER && MSDOS_COMPILER!=WIN32C
  54         char cwd[FILENAME_MAX+1];
  55 #endif
  56
  57         /*
  58          * Print the command which is to be executed,
  59          * unless the command starts with a "-".
  60          */
  61         if (cmd[0] == '-')
  62                 cmd++;
  63         else
  64         {
  65                 clear_bot();
  66                 putstr("!");
  67                 putstr(cmd);
  68                 putstr("\n");
  69         }
  70
  71 #if MSDOS_COMPILER
  72 #if MSDOS_COMPILER==WIN32C
  73         if (*cmd == '\0')
  74                 cmd = getenv("COMSPEC");
  75 #else
  76         /*
  77          * Working directory is global on MSDOS.
  78          * The child might change the working directory, so we
  79          * must save and restore CWD across calls to "system",
  80          * or else we won't find our file when we return and
  81          * try to "reedit_ifile" it.
  82          */
  83         getcwd(cwd, FILENAME_MAX);
  84 #endif
  85 #endif
  86
  87         /*
  88          * Close the current input file.
  89          */
  90         save_ifile = save_curr_ifile();
  91         (void) edit_ifile(NULL_IFILE);
  92
  93         /*
  94          * De-initialize the terminal and take out of raw mode.
  95          */
  96         deinit();
  97         flush();        /* Make sure the deinit chars get out */
  98         raw_mode(0);
  99 #if MSDOS_COMPILER==WIN32C
 100         close_getchr();
 101 #endif
 102
 103         /*
 104          * Restore signals to their defaults.
 105          */
 106         init_signals(0);
 107
 108 #if HAVE_DUP
 109         /*
 110          * Force standard input to be the user's terminal
 111          * (the normal standard input), even if less's standard input
 112          * is coming from a pipe.
 113          */
 114         inp = dup(0);
 115         close(0);
 116 #if OS2
 117         /* The __open() system call translates "/dev/tty" to "con". */
 118         if (__open("/dev/tty", OPEN_READ) < 0)
 119 #else
 120         if (open("/dev/tty", OPEN_READ) < 0)
 121 #endif
 122                 dup(inp);
 123 #endif
 124
 125         /*
 126          * Pass the command to the system to be executed.
 127          * If we have a SHELL environment variable, use
 128          * <$SHELL -c "command"> instead of just <command>.
 129          * If the command is empty, just invoke a shell.
 130          */
 131 #if HAVE_SHELL
 132         p = NULL;
 133         if ((shell = lgetenv("SHELL")) != NULL && *shell != '\0')
 134         {
 135                 if (*cmd == '\0')
 136                         p = save(shell);
 137                 else
 138                 {
 139                         char *esccmd = shell_quote(cmd);
 140                         if (esccmd != NULL)
 141                         {
 142                                 int len = strlen(shell) + strlen(esccmd) + 5;
 143                                 p = (char *) ecalloc(len, sizeof(char));
 144                                 SNPRINTF3(p, len, "%s %s %s", shell, shell_coption(), esccmd);
 145                                 free(esccmd);
 146                         }
 147                 }
 148         }
 149         if (p == NULL)
 150         {
 151                 if (*cmd == '\0')
 152                         p = save("sh");
 153                 else
 154                         p = save(cmd);
 155         }
 156         system(p);
 157         free(p);
 158 #else
 159 #if MSDOS_COMPILER==DJGPPC
 160         /*
 161          * Make stdin of the child be in cooked mode.
 162          */
 163         setmode(0, O_TEXT);
 164         /*
 165          * We don't need to catch signals of the child (it
 166          * also makes trouble with some DPMI servers).
 167          */
 168         __djgpp_exception_toggle();
 169         system(cmd);
 170         __djgpp_exception_toggle();
 171 #else
 172         system(cmd);
 173 #endif
 174 #endif
 175
 176 #if HAVE_DUP
 177         /*
 178          * Restore standard input, reset signals, raw mode, etc.
 179          */
 180         close(0);
 181         dup(inp);
 182         close(inp);
 183 #endif
 184
 185 #if MSDOS_COMPILER==WIN32C
 186         open_getchr();
 187 #endif
 188         init_signals(1);
 189         raw_mode(1);
 190         if (donemsg != NULL)
 191         {
 192                 putstr(donemsg);
 193                 putstr("  (press RETURN)");
 194                 get_return();
 195                 putchr('\n');
 196                 flush();
 197         }
 198         init();
 199         screen_trashed = 1;
 200
 201 #if MSDOS_COMPILER && MSDOS_COMPILER!=WIN32C
 202         /*
 203          * Restore the previous directory (possibly
 204          * changed by the child program we just ran).
 205          */
 206         chdir(cwd);
 207 #if MSDOS_COMPILER != DJGPPC
 208         /*
 209          * Some versions of chdir() don't change to the drive
 210          * which is part of CWD.  (DJGPP does this in chdir.)
 211          */
 212         if (cwd[1] == ':')
 213         {
 214                 if (cwd[0] >= 'a' && cwd[0] <= 'z')
 215                         setdisk(cwd[0] - 'a');
 216                 else if (cwd[0] >= 'A' && cwd[0] <= 'Z')
 217                         setdisk(cwd[0] - 'A');
 218         }
 219 #endif
 220 #endif
 221
 222         /*
 223          * Reopen the current input file.
 224          */
 225         reedit_ifile(save_ifile);
 226
 227 #if defined(SIGWINCH) || defined(SIGWIND)
 228         /*
 229          * Since we were ignoring window change signals while we executed
 230          * the system command, we must assume the window changed.
 231          * Warning: this leaves a signal pending (in "sigs"),
 232          * so psignals() should be called soon after lsystem().
 233          */
 234         winch(0);
 235 #endif
 236 }
 237
 238 #endif
 239
 240 #if PIPEC
 241
 242 /*
 243  * Pipe a section of the input file into the given shell command.
 244  * The section to be piped is the section "between" the current
 245  * position and the position marked by the given letter.
 246  *
 247  * If the mark is after the current screen, the section between
 248  * the top line displayed and the mark is piped.
 249  * If the mark is before the current screen, the section between
 250  * the mark and the bottom line displayed is piped.
 251  * If the mark is on the current screen, or if the mark is ".",
 252  * the whole current screen is piped.
 253  */
 254         public int
 255 pipe_mark(c, cmd)
 256         int c;
 257         char *cmd;
 258 {
 259         POSITION mpos, tpos, bpos;
 260
 261         /*
 262          * mpos = the marked position.
 263          * tpos = top of screen.
 264          * bpos = bottom of screen.
 265          */
 266         mpos = markpos(c);
 267         if (mpos == NULL_POSITION)
 268                 return (-1);
 269         tpos = position(TOP);
 270         if (tpos == NULL_POSITION)
 271                 tpos = ch_zero();
 272         bpos = position(BOTTOM);
 273
 274         if (c == '.')
 275                 return (pipe_data(cmd, tpos, bpos));
 276         else if (mpos <= tpos)
 277                 return (pipe_data(cmd, mpos, bpos));
 278         else if (bpos == NULL_POSITION)
 279                 return (pipe_data(cmd, tpos, bpos));
 280         else
 281                 return (pipe_data(cmd, tpos, mpos));
 282 }
 283
 284 /*
 285  * Create a pipe to the given shell command.
 286  * Feed it the file contents between the positions spos and epos.
 287  */
 288         public int
 289 pipe_data(cmd, spos, epos)
 290         char *cmd;
 291         POSITION spos;
 292         POSITION epos;
 293 {
 294         register FILE *f;
 295         register int c;
 296
 297         /*
 298          * This is structured much like lsystem().
 299          * Since we're running a shell program, we must be careful
 300          * to perform the necessary deinitialization before running
 301          * the command, and reinitialization after it.
 302          */
 303         if (ch_seek(spos) != 0)
 304         {
 305                 error("Cannot seek to start position", NULL_PARG);
 306                 return (-1);
 307         }
 308
 309         if ((f = popen(cmd, "w")) == NULL)
 310         {
 311                 error("Cannot create pipe", NULL_PARG);
 312                 return (-1);
 313         }
 314         clear_bot();
 315         putstr("!");
 316         putstr(cmd);
 317         putstr("\n");
 318
 319         deinit();
 320         flush();
 321         raw_mode(0);
 322         init_signals(0);
 323 #if MSDOS_COMPILER==WIN32C
 324         close_getchr();
 325 #endif
 326 #ifdef SIGPIPE
 327         LSIGNAL(SIGPIPE, SIG_IGN);
 328 #endif
 329
 330         c = EOI;
 331         while (epos == NULL_POSITION || spos++ <= epos)
 332         {
 333                 /*
 334                  * Read a character from the file and give it to the pipe.
 335                  */
 336                 c = ch_forw_get();
 337                 if (c == EOI)
 338                         break;
 339                 if (putc(c, f) == EOF)
 340                         break;
 341         }
 342
 343         /*
 344          * Finish up the last line.
 345          */
 346         while (c != '\n' && c != EOI )
 347         {
 348                 c = ch_forw_get();
 349                 if (c == EOI)
 350                         break;
 351                 if (putc(c, f) == EOF)
 352                         break;
 353         }
 354
 355         pclose(f);
 356
 357 #ifdef SIGPIPE
 358         LSIGNAL(SIGPIPE, SIG_DFL);
 359 #endif
 360 #if MSDOS_COMPILER==WIN32C
 361         open_getchr();
 362 #endif
 363         init_signals(1);
 364         raw_mode(1);
 365         init();
 366         screen_trashed = 1;
 367 #if defined(SIGWINCH) || defined(SIGWIND)
 368         /* {{ Probably don't need this here. }} */
 369         winch(0);
 370 #endif
 371         return (0);
 372 }
 373
 374 #endif