1 /* 2 * Copyright (C) 1984-2024 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 * Routines to execute other programs. 13 * Necessarily very OS dependent. 14 */ 15 16 #include "less.h" 17 #include <signal.h> 18 #include "position.h" 19 20 #if MSDOS_COMPILER 21 #include <dos.h> 22 #if MSDOS_COMPILER==WIN32C && defined(MINGW) 23 #include <direct.h> 24 #define setdisk(n) _chdrive((n)+1) 25 #else 26 #ifdef _MSC_VER 27 #include <direct.h> 28 #define setdisk(n) _chdrive((n)+1) 29 #else 30 #include <dir.h> 31 #endif 32 #endif 33 #endif 34 35 extern IFILE curr_ifile; 36 37 38 #if HAVE_SYSTEM 39 40 /* 41 * Pass the specified command to a shell to be executed. 42 * Like plain "system()", but handles resetting terminal modes, etc. 43 */ 44 public void lsystem(constant char *cmd, constant char *donemsg) 45 { 46 int inp; 47 #if HAVE_SHELL 48 constant char *shell; 49 char *p; 50 #endif 51 IFILE save_ifile; 52 #if MSDOS_COMPILER && MSDOS_COMPILER!=WIN32C 53 char cwd[FILENAME_MAX+1]; 54 #endif 55 56 /* 57 * Print the command which is to be executed, 58 * unless the command starts with a "-". 59 */ 60 if (cmd[0] == '-') 61 cmd++; 62 else 63 { 64 clear_bot(); 65 putstr("!"); 66 putstr(cmd); 67 putstr("\n"); 68 } 69 70 #if MSDOS_COMPILER 71 #if MSDOS_COMPILER==WIN32C 72 if (*cmd == '\0') 73 cmd = getenv("COMSPEC"); 74 #else 75 /* 76 * Working directory is global on MSDOS. 77 * The child might change the working directory, so we 78 * must save and restore CWD across calls to "system", 79 * or else we won't find our file when we return and 80 * try to "reedit_ifile" it. 81 */ 82 getcwd(cwd, FILENAME_MAX); 83 #endif 84 #endif 85 86 /* 87 * Close the current input file. 88 */ 89 save_ifile = save_curr_ifile(); 90 (void) edit_ifile(NULL_IFILE); 91 92 /* 93 * De-initialize the terminal and take out of raw mode. 94 */ 95 deinit(); 96 flush(); /* Make sure the deinit chars get out */ 97 raw_mode(0); 98 #if MSDOS_COMPILER==WIN32C 99 close_getchr(); 100 #endif 101 102 /* 103 * Restore signals to their defaults. 104 */ 105 init_signals(0); 106 107 #if HAVE_DUP 108 /* 109 * Force standard input to be the user's terminal 110 * (the normal standard input), even if less's standard input 111 * is coming from a pipe. 112 */ 113 inp = dup(0); 114 close(0); 115 #if !MSDOS_COMPILER 116 if (open_tty() < 0) 117 #endif 118 dup(inp); 119 #endif 120 121 /* 122 * Pass the command to the system to be executed. 123 * If we have a SHELL environment variable, use 124 * <$SHELL -c "command"> instead of just <command>. 125 * If the command is empty, just invoke a shell. 126 */ 127 #if HAVE_SHELL 128 p = NULL; 129 if ((shell = lgetenv("SHELL")) != NULL && *shell != '\0') 130 { 131 if (*cmd == '\0') 132 p = save(shell); 133 else 134 { 135 char *esccmd = shell_quote(cmd); 136 if (esccmd != NULL) 137 { 138 size_t len = strlen(shell) + strlen(esccmd) + 5; 139 p = (char *) ecalloc(len, sizeof(char)); 140 SNPRINTF3(p, len, "%s %s %s", shell, shell_coption(), esccmd); 141 free(esccmd); 142 } 143 } 144 } 145 if (p == NULL) 146 { 147 if (*cmd == '\0') 148 p = save("sh"); 149 else 150 p = save(cmd); 151 } 152 system(p); 153 free(p); 154 #else 155 #if MSDOS_COMPILER==DJGPPC 156 /* 157 * Make stdin of the child be in cooked mode. 158 */ 159 setmode(0, O_TEXT); 160 /* 161 * We don't need to catch signals of the child (it 162 * also makes trouble with some DPMI servers). 163 */ 164 __djgpp_exception_toggle(); 165 system(cmd); 166 __djgpp_exception_toggle(); 167 #else 168 system(cmd); 169 #endif 170 #endif 171 172 #if HAVE_DUP 173 /* 174 * Restore standard input, reset signals, raw mode, etc. 175 */ 176 close(0); 177 dup(inp); 178 close(inp); 179 #endif 180 181 #if MSDOS_COMPILER==WIN32C 182 open_getchr(); 183 #endif 184 init_signals(1); 185 raw_mode(1); 186 if (donemsg != NULL) 187 { 188 putstr(donemsg); 189 putstr(" (press RETURN)"); 190 get_return(); 191 putchr('\n'); 192 flush(); 193 } 194 init(); 195 screen_trashed(); 196 197 #if MSDOS_COMPILER && MSDOS_COMPILER!=WIN32C 198 /* 199 * Restore the previous directory (possibly 200 * changed by the child program we just ran). 201 */ 202 chdir(cwd); 203 #if MSDOS_COMPILER != DJGPPC 204 /* 205 * Some versions of chdir() don't change to the drive 206 * which is part of CWD. (DJGPP does this in chdir.) 207 */ 208 if (cwd[1] == ':') 209 { 210 if (cwd[0] >= 'a' && cwd[0] <= 'z') 211 setdisk(cwd[0] - 'a'); 212 else if (cwd[0] >= 'A' && cwd[0] <= 'Z') 213 setdisk(cwd[0] - 'A'); 214 } 215 #endif 216 #endif 217 218 /* 219 * Reopen the current input file. 220 */ 221 reedit_ifile(save_ifile); 222 223 #if defined(SIGWINCH) || defined(SIGWIND) 224 /* 225 * Since we were ignoring window change signals while we executed 226 * the system command, we must assume the window changed. 227 * Warning: this leaves a signal pending (in "sigs"), 228 * so psignals() should be called soon after lsystem(). 229 */ 230 winch(0); 231 #endif 232 } 233 234 #endif 235 236 #if PIPEC 237 238 /* 239 * Pipe a section of the input file into the given shell command. 240 * The section to be piped is the section "between" the current 241 * position and the position marked by the given letter. 242 * 243 * If the mark is after the current screen, the section between 244 * the top line displayed and the mark is piped. 245 * If the mark is before the current screen, the section between 246 * the mark and the bottom line displayed is piped. 247 * If the mark is on the current screen, or if the mark is ".", 248 * the whole current screen is piped. 249 */ 250 public int pipe_mark(char c, constant char *cmd) 251 { 252 POSITION mpos, tpos, bpos; 253 254 /* 255 * mpos = the marked position. 256 * tpos = top of screen. 257 * bpos = bottom of screen. 258 */ 259 mpos = markpos(c); 260 if (mpos == NULL_POSITION) 261 return (-1); 262 tpos = position(TOP); 263 if (tpos == NULL_POSITION) 264 tpos = ch_zero(); 265 bpos = position(BOTTOM); 266 267 if (c == '.') 268 return (pipe_data(cmd, tpos, bpos)); 269 else if (mpos <= tpos) 270 return (pipe_data(cmd, mpos, bpos)); 271 else if (bpos == NULL_POSITION) 272 return (pipe_data(cmd, tpos, bpos)); 273 else 274 return (pipe_data(cmd, tpos, mpos)); 275 } 276 277 /* 278 * Create a pipe to the given shell command. 279 * Feed it the file contents between the positions spos and epos. 280 */ 281 public int pipe_data(constant char *cmd, POSITION spos, POSITION epos) 282 { 283 FILE *f; 284 int c; 285 286 /* 287 * This is structured much like lsystem(). 288 * Since we're running a shell program, we must be careful 289 * to perform the necessary deinitialization before running 290 * the command, and reinitialization after it. 291 */ 292 if (ch_seek(spos) != 0) 293 { 294 error("Cannot seek to start position", NULL_PARG); 295 return (-1); 296 } 297 298 if ((f = popen(cmd, "w")) == NULL) 299 { 300 error("Cannot create pipe", NULL_PARG); 301 return (-1); 302 } 303 clear_bot(); 304 putstr("!"); 305 putstr(cmd); 306 putstr("\n"); 307 308 deinit(); 309 flush(); 310 raw_mode(0); 311 init_signals(0); 312 #if MSDOS_COMPILER==WIN32C 313 close_getchr(); 314 #endif 315 #ifdef SIGPIPE 316 LSIGNAL(SIGPIPE, SIG_IGN); 317 #endif 318 319 c = EOI; 320 while (epos == NULL_POSITION || spos++ <= epos) 321 { 322 /* 323 * Read a character from the file and give it to the pipe. 324 */ 325 c = ch_forw_get(); 326 if (c == EOI) 327 break; 328 if (putc(c, f) == EOF) 329 break; 330 } 331 332 /* 333 * Finish up the last line. 334 */ 335 while (c != '\n' && c != EOI ) 336 { 337 c = ch_forw_get(); 338 if (c == EOI) 339 break; 340 if (putc(c, f) == EOF) 341 break; 342 } 343 344 pclose(f); 345 346 #ifdef SIGPIPE 347 LSIGNAL(SIGPIPE, SIG_DFL); 348 #endif 349 #if MSDOS_COMPILER==WIN32C 350 open_getchr(); 351 #endif 352 init_signals(1); 353 raw_mode(1); 354 init(); 355 screen_trashed(); 356 #if defined(SIGWINCH) || defined(SIGWIND) 357 /* {{ Probably don't need this here. }} */ 358 winch(0); 359 #endif 360 return (0); 361 } 362 363 #endif 364