| 1 | /* |
| 2 | * Copyright (c) 1980 Regents of the University of California. |
| 3 | * All rights reserved. The Berkeley Software License Agreement |
| 4 | * specifies the terms and conditions for redistribution. |
| 5 | * |
| 6 | * @(#)sh.h 5.6 (Berkeley) 2/25/91 |
| 7 | */ |
| 8 | #include <sys/param.h> |
| 9 | #include <sys/time.h> |
| 10 | #include <sys/resource.h> |
| 11 | #include <sys/stat.h> |
| 12 | #include <sys/signal.h> |
| 13 | #include <errno.h> |
| 14 | #include <setjmp.h> |
| 15 | #include "sh.local.h" |
| 16 | #include "sh.char.h" |
| 17 | |
| 18 | /* |
| 19 | * C shell |
| 20 | * |
| 21 | * Bill Joy, UC Berkeley |
| 22 | * October, 1978; May 1980 |
| 23 | * |
| 24 | * Jim Kulp, IIASA, Laxenburg Austria |
| 25 | * April, 1980 |
| 26 | */ |
| 27 | |
| 28 | #define isdir(d) ((d.st_mode & S_IFMT) == S_IFDIR) |
| 29 | |
| 30 | typedef char bool; |
| 31 | |
| 32 | #define eq(a, b) (strcmp(a, b) == 0) |
| 33 | |
| 34 | /* |
| 35 | * Global flags |
| 36 | */ |
| 37 | bool chkstop; /* Warned of stopped jobs... allow exit */ |
| 38 | bool didfds; /* Have setup i/o fd's for child */ |
| 39 | bool doneinp; /* EOF indicator after reset from readc */ |
| 40 | bool exiterr; /* Exit if error or non-zero exit status */ |
| 41 | bool child; /* Child shell ... errors cause exit */ |
| 42 | bool haderr; /* Reset was because of an error */ |
| 43 | bool intty; /* Input is a tty */ |
| 44 | bool intact; /* We are interactive... therefore prompt */ |
| 45 | bool justpr; /* Just print because of :p hist mod */ |
| 46 | bool loginsh; /* We are a loginsh -> .login/.logout */ |
| 47 | bool neednote; /* Need to pnotify() */ |
| 48 | bool noexec; /* Don't execute, just syntax check */ |
| 49 | bool pjobs; /* want to print jobs if interrupted */ |
| 50 | bool setintr; /* Set interrupts on/off -> Wait intr... */ |
| 51 | bool timflg; /* Time the next waited for command */ |
| 52 | bool havhash; /* path hashing is available */ |
| 53 | #ifdef FILEC |
| 54 | bool filec; /* doing filename expansion */ |
| 55 | #endif |
| 56 | |
| 57 | /* |
| 58 | * Global i/o info |
| 59 | */ |
| 60 | char *arginp; /* Argument input for sh -c and internal `xx` */ |
| 61 | int onelflg; /* 2 -> need line for -t, 1 -> exit on read */ |
| 62 | char *file; /* Name of shell file for $0 */ |
| 63 | |
| 64 | char *err; /* Error message from scanner/parser */ |
| 65 | int errno; /* Error from C library routines */ |
| 66 | char *shtemp; /* Temp name for << shell files in /tmp */ |
| 67 | struct timeval time0; /* Time at which the shell started */ |
| 68 | struct rusage ru0; |
| 69 | |
| 70 | /* |
| 71 | * Miscellany |
| 72 | */ |
| 73 | char *doldol; /* Character pid for $$ */ |
| 74 | int uid; /* Invokers uid */ |
| 75 | time_t chktim; /* Time mail last checked */ |
| 76 | int shpgrp; /* Pgrp of shell */ |
| 77 | int tpgrp; /* Terminal process group */ |
| 78 | /* If tpgrp is -1, leave tty alone! */ |
| 79 | int opgrp; /* Initial pgrp and tty pgrp */ |
| 80 | |
| 81 | /* |
| 82 | * These are declared here because they want to be |
| 83 | * initialized in sh.init.c (to allow them to be made readonly) |
| 84 | */ |
| 85 | |
| 86 | struct biltins { |
| 87 | char *bname; |
| 88 | int (*bfunct)(); |
| 89 | short minargs, maxargs; |
| 90 | } bfunc[]; |
| 91 | extern int nbfunc; |
| 92 | |
| 93 | struct srch { |
| 94 | char *s_name; |
| 95 | short s_value; |
| 96 | } srchn[]; |
| 97 | extern int nsrchn; |
| 98 | |
| 99 | /* |
| 100 | * To be able to redirect i/o for builtins easily, the shell moves the i/o |
| 101 | * descriptors it uses away from 0,1,2. |
| 102 | * Ideally these should be in units which are closed across exec's |
| 103 | * (this saves work) but for version 6, this is not usually possible. |
| 104 | * The desired initial values for these descriptors are defined in |
| 105 | * sh.local.h. |
| 106 | */ |
| 107 | short SHIN; /* Current shell input (script) */ |
| 108 | short SHOUT; /* Shell output */ |
| 109 | short SHDIAG; /* Diagnostic output... shell errs go here */ |
| 110 | short OLDSTD; /* Old standard input (def for cmds) */ |
| 111 | |
| 112 | /* |
| 113 | * Error control |
| 114 | * |
| 115 | * Errors in scanning and parsing set up an error message to be printed |
| 116 | * at the end and complete. Other errors always cause a reset. |
| 117 | * Because of source commands and .cshrc we need nested error catches. |
| 118 | */ |
| 119 | |
| 120 | jmp_buf reslab; |
| 121 | |
| 122 | #define setexit() ((void) setjmp(reslab)) |
| 123 | #define reset() longjmp(reslab, 0) |
| 124 | /* Should use structure assignment here */ |
| 125 | #define getexit(a) bcopy((char *)reslab, (char *)(a), sizeof reslab) |
| 126 | #define resexit(a) bcopy(((char *)(a)), (char *)reslab, sizeof reslab) |
| 127 | |
| 128 | char *gointr; /* Label for an onintr transfer */ |
| 129 | sig_t parintr; /* Parents interrupt catch */ |
| 130 | sig_t parterm; /* Parents terminate catch */ |
| 131 | |
| 132 | /* |
| 133 | * Lexical definitions. |
| 134 | * |
| 135 | * All lexical space is allocated dynamically. |
| 136 | * The eighth bit of characters is used to prevent recognition, |
| 137 | * and eventually stripped. |
| 138 | */ |
| 139 | #define QUOTE 0200 /* Eighth char bit used internally for 'ing */ |
| 140 | #define TRIM 0177 /* Mask to strip quote bit */ |
| 141 | |
| 142 | /* |
| 143 | * Each level of input has a buffered input structure. |
| 144 | * There are one or more blocks of buffered input for each level, |
| 145 | * exactly one if the input is seekable and tell is available. |
| 146 | * In other cases, the shell buffers enough blocks to keep all loops |
| 147 | * in the buffer. |
| 148 | */ |
| 149 | struct Bin { |
| 150 | off_t Bfseekp; /* Seek pointer */ |
| 151 | off_t Bfbobp; /* Seekp of beginning of buffers */ |
| 152 | off_t Bfeobp; /* Seekp of end of buffers */ |
| 153 | short Bfblocks; /* Number of buffer blocks */ |
| 154 | char **Bfbuf; /* The array of buffer blocks */ |
| 155 | } B; |
| 156 | |
| 157 | #define fseekp B.Bfseekp |
| 158 | #define fbobp B.Bfbobp |
| 159 | #define feobp B.Bfeobp |
| 160 | #define fblocks B.Bfblocks |
| 161 | #define fbuf B.Bfbuf |
| 162 | |
| 163 | #define btell() fseekp |
| 164 | |
| 165 | #ifndef btell |
| 166 | off_t btell(); |
| 167 | #endif |
| 168 | |
| 169 | /* |
| 170 | * The shell finds commands in loops by reseeking the input |
| 171 | * For whiles, in particular, it reseeks to the beginning of the |
| 172 | * line the while was on; hence the while placement restrictions. |
| 173 | */ |
| 174 | off_t lineloc; |
| 175 | |
| 176 | #ifdef TELL |
| 177 | bool cantell; /* Is current source tellable ? */ |
| 178 | #endif |
| 179 | |
| 180 | /* |
| 181 | * Input lines are parsed into doubly linked circular |
| 182 | * lists of words of the following form. |
| 183 | */ |
| 184 | struct wordent { |
| 185 | char *word; |
| 186 | struct wordent *prev; |
| 187 | struct wordent *next; |
| 188 | }; |
| 189 | |
| 190 | /* |
| 191 | * During word building, both in the initial lexical phase and |
| 192 | * when expanding $ variable substitutions, expansion by `!' and `$' |
| 193 | * must be inhibited when reading ahead in routines which are themselves |
| 194 | * processing `!' and `$' expansion or after characters such as `\' or in |
| 195 | * quotations. The following flags are passed to the getC routines |
| 196 | * telling them which of these substitutions are appropriate for the |
| 197 | * next character to be returned. |
| 198 | */ |
| 199 | #define DODOL 1 |
| 200 | #define DOEXCL 2 |
| 201 | #define DOALL DODOL|DOEXCL |
| 202 | |
| 203 | /* |
| 204 | * Labuf implements a general buffer for lookahead during lexical operations. |
| 205 | * Text which is to be placed in the input stream can be stuck here. |
| 206 | * We stick parsed ahead $ constructs during initial input, |
| 207 | * process id's from `$$', and modified variable values (from qualifiers |
| 208 | * during expansion in sh.dol.c) here. |
| 209 | */ |
| 210 | char labuf[BUFSIZ]; |
| 211 | |
| 212 | char *lap; |
| 213 | |
| 214 | /* |
| 215 | * Parser structure |
| 216 | * |
| 217 | * Each command is parsed to a tree of command structures and |
| 218 | * flags are set bottom up during this process, to be propagated down |
| 219 | * as needed during the semantics/exeuction pass (sh.sem.c). |
| 220 | */ |
| 221 | struct command { |
| 222 | short t_dtyp; /* Type of node */ |
| 223 | short t_dflg; /* Flags, e.g. FAND|... */ |
| 224 | union { |
| 225 | char *T_dlef; /* Input redirect word */ |
| 226 | struct command *T_dcar; /* Left part of list/pipe */ |
| 227 | } L; |
| 228 | union { |
| 229 | char *T_drit; /* Output redirect word */ |
| 230 | struct command *T_dcdr; /* Right part of list/pipe */ |
| 231 | } R; |
| 232 | #define t_dlef L.T_dlef |
| 233 | #define t_dcar L.T_dcar |
| 234 | #define t_drit R.T_drit |
| 235 | #define t_dcdr R.T_dcdr |
| 236 | char **t_dcom; /* Command/argument vector */ |
| 237 | struct command *t_dspr; /* Pointer to ()'d subtree */ |
| 238 | short t_nice; |
| 239 | }; |
| 240 | |
| 241 | #define TCOM 1 /* t_dcom <t_dlef >t_drit */ |
| 242 | #define TPAR 2 /* ( t_dspr ) <t_dlef >t_drit */ |
| 243 | #define TFIL 3 /* t_dlef | t_drit */ |
| 244 | #define TLST 4 /* t_dlef ; t_drit */ |
| 245 | #define TOR 5 /* t_dlef || t_drit */ |
| 246 | #define TAND 6 /* t_dlef && t_drit */ |
| 247 | |
| 248 | #define FSAVE (FNICE|FTIME|FNOHUP) /* save these when re-doing */ |
| 249 | |
| 250 | #define FAND (1<<0) /* executes in background */ |
| 251 | #define FCAT (1<<1) /* output is redirected >> */ |
| 252 | #define FPIN (1<<2) /* input is a pipe */ |
| 253 | #define FPOU (1<<3) /* output is a pipe */ |
| 254 | #define FPAR (1<<4) /* don't fork, last ()ized cmd */ |
| 255 | #define FINT (1<<5) /* should be immune from intr's */ |
| 256 | /* spare */ |
| 257 | #define FDIAG (1<<7) /* redirect unit 2 with unit 1 */ |
| 258 | #define FANY (1<<8) /* output was ! */ |
| 259 | #define FHERE (1<<9) /* input redirection is << */ |
| 260 | #define FREDO (1<<10) /* reexec aft if, repeat,... */ |
| 261 | #define FNICE (1<<11) /* t_nice is meaningful */ |
| 262 | #define FNOHUP (1<<12) /* nohup this command */ |
| 263 | #define FTIME (1<<13) /* time this command */ |
| 264 | |
| 265 | /* |
| 266 | * The keywords for the parser |
| 267 | */ |
| 268 | #define ZBREAK 0 |
| 269 | #define ZBRKSW 1 |
| 270 | #define ZCASE 2 |
| 271 | #define ZDEFAULT 3 |
| 272 | #define ZELSE 4 |
| 273 | #define ZEND 5 |
| 274 | #define ZENDIF 6 |
| 275 | #define ZENDSW 7 |
| 276 | #define ZEXIT 8 |
| 277 | #define ZFOREACH 9 |
| 278 | #define ZGOTO 10 |
| 279 | #define ZIF 11 |
| 280 | #define ZLABEL 12 |
| 281 | #define ZLET 13 |
| 282 | #define ZSET 14 |
| 283 | #define ZSWITCH 15 |
| 284 | #define ZTEST 16 |
| 285 | #define ZTHEN 17 |
| 286 | #define ZWHILE 18 |
| 287 | |
| 288 | /* |
| 289 | * Structure defining the existing while/foreach loops at this |
| 290 | * source level. Loops are implemented by seeking back in the |
| 291 | * input. For foreach (fe), the word list is attached here. |
| 292 | */ |
| 293 | struct whyle { |
| 294 | off_t w_start; /* Point to restart loop */ |
| 295 | off_t w_end; /* End of loop (0 if unknown) */ |
| 296 | char **w_fe, **w_fe0; /* Current/initial wordlist for fe */ |
| 297 | char *w_fename; /* Name for fe */ |
| 298 | struct whyle *w_next; /* Next (more outer) loop */ |
| 299 | } *whyles; |
| 300 | |
| 301 | /* |
| 302 | * Variable structure |
| 303 | * |
| 304 | * Aliases and variables are stored in AVL balanced binary trees. |
| 305 | */ |
| 306 | struct varent { |
| 307 | char **vec; /* Array of words which is the value */ |
| 308 | char *v_name; /* Name of variable/alias */ |
| 309 | struct varent *v_link[3]; /* The links, see below */ |
| 310 | int v_bal; /* Balance factor */ |
| 311 | } shvhed, aliases; |
| 312 | #define v_left v_link[0] |
| 313 | #define v_right v_link[1] |
| 314 | #define v_parent v_link[2] |
| 315 | |
| 316 | struct varent *adrof1(); |
| 317 | #define adrof(v) adrof1(v, &shvhed) |
| 318 | #define value(v) value1(v, &shvhed) |
| 319 | |
| 320 | /* |
| 321 | * The following are for interfacing redo substitution in |
| 322 | * aliases to the lexical routines. |
| 323 | */ |
| 324 | struct wordent *alhistp; /* Argument list (first) */ |
| 325 | struct wordent *alhistt; /* Node after last in arg list */ |
| 326 | char **alvec; /* The (remnants of) alias vector */ |
| 327 | |
| 328 | /* |
| 329 | * Filename/command name expansion variables |
| 330 | */ |
| 331 | short gflag; /* After tglob -> is globbing needed? */ |
| 332 | |
| 333 | /* |
| 334 | * A reasonable limit on number of arguments would seem to be |
| 335 | * the maximum number of characters in an arg list / 6. |
| 336 | */ |
| 337 | #define GAVSIZ NCARGS / 6 |
| 338 | |
| 339 | /* |
| 340 | * Variables for filename expansion |
| 341 | */ |
| 342 | char **gargv; /* Pointer to the (stack) arglist */ |
| 343 | short gargc; /* Number args in gargv */ |
| 344 | |
| 345 | /* |
| 346 | * Variables for command expansion. |
| 347 | */ |
| 348 | char **pargv; /* Pointer to the argv list space */ |
| 349 | char *pargs; /* Pointer to start current word */ |
| 350 | short pargc; /* Count of arguments in pargv */ |
| 351 | short pnleft; /* Number of chars left in pargs */ |
| 352 | char *pargcp; /* Current index into pargs */ |
| 353 | |
| 354 | /* |
| 355 | * History list |
| 356 | * |
| 357 | * Each history list entry contains an embedded wordlist |
| 358 | * from the scanner, a number for the event, and a reference count |
| 359 | * to aid in discarding old entries. |
| 360 | * |
| 361 | * Essentially "invisible" entries are put on the history list |
| 362 | * when history substitution includes modifiers, and thrown away |
| 363 | * at the next discarding since their event numbers are very negative. |
| 364 | */ |
| 365 | struct Hist { |
| 366 | struct wordent Hlex; |
| 367 | int Hnum; |
| 368 | int Href; |
| 369 | struct Hist *Hnext; |
| 370 | } Histlist; |
| 371 | |
| 372 | struct wordent paraml; /* Current lexical word list */ |
| 373 | int eventno; /* Next events number */ |
| 374 | int lastev; /* Last event reference (default) */ |
| 375 | |
| 376 | char HIST; /* history invocation character */ |
| 377 | char HISTSUB; /* auto-substitute character */ |
| 378 | |
| 379 | /* |
| 380 | * In lines for frequently called functions |
| 381 | */ |
| 382 | #define XFREE(cp) { \ |
| 383 | extern char end[]; \ |
| 384 | char stack; \ |
| 385 | if ((cp) >= end && (cp) < &stack) \ |
| 386 | free(cp); \ |
| 387 | } |
| 388 | char *alloctmp; |
| 389 | #define xalloc(i) ((alloctmp = malloc(i)) ? alloctmp : (char *)nomem(i)) |
| 390 | #define xrealloc(p, i) ((alloctmp = realloc(p, i)) ? alloctmp : (char *)nomem(i)) |
| 391 | |
| 392 | char *Dfix1(); |
| 393 | char **blkcat(); |
| 394 | char **blkcpy(); |
| 395 | char **blkend(); |
| 396 | char **blkspl(); |
| 397 | char *calloc(); |
| 398 | char *malloc(); |
| 399 | char *realloc(); |
| 400 | char *cname(); |
| 401 | char **copyblk(); |
| 402 | char **dobackp(); |
| 403 | char *domod(); |
| 404 | struct wordent *dosub(); |
| 405 | char *exp3(); |
| 406 | char *exp3a(); |
| 407 | char *exp4(); |
| 408 | char *exp5(); |
| 409 | char *exp6(); |
| 410 | struct Hist *enthist(); |
| 411 | struct Hist *findev(); |
| 412 | struct wordent *freenod(); |
| 413 | char *getenv(); |
| 414 | char *getinx(); |
| 415 | struct varent *getvx(); |
| 416 | struct passwd *getpwnam(); |
| 417 | struct wordent *gethent(); |
| 418 | struct wordent *getsub(); |
| 419 | char *getwd(); |
| 420 | char **globall(); |
| 421 | char *globone(); |
| 422 | char *index(); |
| 423 | struct biltins *isbfunc(); |
| 424 | off_t lseek(); |
| 425 | char *operate(); |
| 426 | int phup(); |
| 427 | void pintr(); |
| 428 | void pchild(); |
| 429 | char *putn(); |
| 430 | char *rindex(); |
| 431 | char **saveblk(); |
| 432 | char *savestr(); |
| 433 | char *strcat(); |
| 434 | char *strcpy(); |
| 435 | char *strend(); |
| 436 | char *strings(); |
| 437 | char *strip(); |
| 438 | char *strspl(); |
| 439 | char *subword(); |
| 440 | struct command *syntax(); |
| 441 | struct command *syn0(); |
| 442 | struct command *syn1(); |
| 443 | struct command *syn1a(); |
| 444 | struct command *syn1b(); |
| 445 | struct command *syn2(); |
| 446 | struct command *syn3(); |
| 447 | char *value1(); |
| 448 | char *xhome(); |
| 449 | char *xname(); |
| 450 | char *xset(); |
| 451 | |
| 452 | #define NOSTR ((char *) 0) |
| 453 | |
| 454 | /* |
| 455 | * setname is a macro to save space (see sh.err.c) |
| 456 | */ |
| 457 | char *bname; |
| 458 | #define setname(a) (bname = (a)) |
| 459 | |
| 460 | #ifdef VFORK |
| 461 | char *Vsav; |
| 462 | char **Vav; |
| 463 | char *Vdp; |
| 464 | #endif |
| 465 | |
| 466 | char **evalvec; |
| 467 | char *evalp; |
| 468 | |
| 469 | struct mesg { |
| 470 | char *iname; /* name from /usr/include */ |
| 471 | char *pname; /* print name */ |
| 472 | } mesg[]; |