1 /* 2 * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 3 * Use is subject to license terms. 4 */ 5 6 /* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */ 7 /* All Rights Reserved */ 8 9 /* 10 * Copyright (c) 1980 Regents of the University of California. 11 * All rights reserved. The Berkeley Software License Agreement 12 * specifies the terms and conditions for redistribution. 13 */ 14 15 #include <stdlib.h> /* MB_xxx, mbxxx(), wcxxx() etc. */ 16 #include <limits.h> 17 #include <sys/time.h> 18 #include <sys/types.h> 19 #include <sys/siginfo.h> 20 #include <sys/ucontext.h> 21 #include <sys/param.h> 22 #include <sys/stat.h> 23 #include <sys/termios.h> 24 #include <sys/ttold.h> 25 #include <errno.h> 26 #include <signal.h> /* std sysV signal.h */ 27 #include <setjmp.h> 28 #include <sys/resource.h> 29 #include <netdb.h> /* for MAXHOSTNAMELEN */ 30 #include "signal.h" /* mainly BSD related signal.h */ 31 #include "sh.local.h" 32 #include "sh.char.h" 33 34 35 #ifdef MBCHAR 36 #if !defined(MB_LEN_MAX) || !defined(MB_CUR_MAX) 37 Error: I need both ANSI macros! 38 #endif 39 #else 40 #if !defined(MB_LEN_MAX) 41 #define MB_LEN_MAX 1 42 #endif 43 #if !defined(MB_CUR_MAX) 44 #define MB_CUR_MAX 1 45 #endif 46 #endif 47 48 #ifndef MBCHAR /* Let's replace the ANSI functions with our own macro 49 * for efficiency! 50 */ 51 #define mbtowc(pwc, pmb, n_is_ignored) ((*(pwc) = *(pmb)), 1) 52 #define wctomb(pmb, wc) ((*(pmb) = ((char)wc)), 1) 53 #endif /* !MBCHAR */ 54 55 /* 56 * C shell 57 * 58 * Bill Joy, UC Berkeley 59 * October, 1978; May 1980 60 * 61 * Jim Kulp, IIASA, Laxenburg Austria 62 * April, 1980 63 */ 64 65 /* 66 * If we are setting the $cwd variable becuz we did a 67 * cd, chdir, pushd, popd command, then set didchdir to 68 * 1. This prevents globbing down when setting $cwd. 69 * However, if the user set $cwd, we want the globbing 70 * done; so, didchdir would be equal to 0 in that case. 71 */ 72 extern int didchdir; 73 74 #define isdir(d) ((d.st_mode & S_IFMT) == S_IFDIR) 75 76 typedef char bool; 77 78 /* 79 * tchar (Tagged CHARacter) is a place holder to keep a QUOTE bit and 80 * a character. 81 * For European language handling, lower 8 bits of tchar is used 82 * to store a character. For other languages, especially Asian, 16 bits 83 * are used to store a character. 84 * Following typedef's assume short int is a 16-bit entity and long int is 85 * a 32-bit entity. 86 * The QUOTE bit tells whether the character is subject to further 87 * interpretation such as history substitution, file mathing, command 88 * subsitution. TRIM is a mask to strip off the QUOTE bit. 89 */ 90 #ifdef MBCHAR /* For multibyte character handling. */ 91 typedef long int tchar; 92 #define QUOTE 0x80000000 93 #define TRIM 0x7fffffff 94 #else /* !MBCHAR */ /* European language requires only 8 bits. */ 95 typedef unsigned short int tchar; 96 #define QUOTE 0x8000 97 #define TRIM 0x00ff 98 #endif /* !MBCHAR */ 99 #define eq(a, b) (strcmp_(a, b) == 0) 100 101 102 /* 103 * Global flags 104 */ 105 extern bool chkstop; /* Warned of stopped jobs... allow exit */ 106 extern bool didfds; /* Have setup i/o fd's for child */ 107 extern bool doneinp; /* EOF indicator after reset from readc */ 108 extern bool exiterr; /* Exit if error or non-zero exit status */ 109 extern bool child; /* Child shell ... errors cause exit */ 110 extern bool haderr; /* Reset was because of an error */ 111 extern bool intty; /* Input is a tty */ 112 extern bool cflg; /* invoked with -c option */ 113 extern bool justpr; /* Just print because of :p hist mod */ 114 extern bool loginsh; /* We are a loginsh -> .login/.logout */ 115 extern bool neednote; /* Need to pnotify() */ 116 extern bool noexec; /* Don't execute, just syntax check */ 117 extern bool pjobs; /* want to print jobs if interrupted */ 118 extern bool setintr; /* Set interrupts on/off -> Wait intr... */ 119 extern bool havhash; /* path hashing is available */ 120 extern bool havhash2; /* cdpath hashing is available */ 121 #ifdef FILEC 122 extern bool filec; /* doing filename expansion */ 123 #endif 124 125 /* 126 * Global i/o info 127 */ 128 extern tchar *arginp; /* Argument input for sh -c and internal `xx` */ 129 extern int onelflg; /* 2 -> need line for -t, 1 -> exit on read */ 130 extern tchar *file; /* Name of shell file for $0 */ 131 132 extern char *err_msg; /* Error message from scanner/parser */ 133 extern struct timeval time0; /* Time at which the shell started */ 134 135 /* 136 * Miscellany 137 */ 138 extern tchar *doldol; /* Character pid for $$ */ 139 extern int uid; /* Invokers uid */ 140 extern int shpgrp; /* Pgrp of shell */ 141 extern int tpgrp; /* Terminal process group */ 142 /* If tpgrp is -1, leave tty alone! */ 143 extern int opgrp; /* Initial pgrp and tty pgrp */ 144 145 /* 146 * These are declared here because they want to be 147 * initialized in sh.init.c (to allow them to be made readonly) 148 */ 149 150 extern struct biltins { 151 tchar *bname; 152 int (*bfunct)(); 153 short minargs, maxargs; 154 } bfunc[]; 155 extern int nbfunc; 156 157 extern struct srch { 158 tchar *s_name; 159 short s_value; 160 } srchn[]; 161 extern int nsrchn; 162 163 /* 164 * To be able to redirect i/o for builtins easily, the shell moves the i/o 165 * descriptors it uses away from 0,1,2. 166 * Ideally these should be in units which are closed across exec's 167 * (this saves work) but for version 6, this is not usually possible. 168 * The desired initial values for these descriptors are defined in 169 * sh.local.h. 170 */ 171 extern short SHIN; /* Current shell input (script) */ 172 extern short SHOUT; /* Shell output */ 173 extern short SHDIAG; /* Diagnostic output... shell errs go here */ 174 extern short OLDSTD; /* Old standard input (def for cmds) */ 175 176 /* 177 * Error control 178 * 179 * Errors in scanning and parsing set up an error message to be printed 180 * at the end and complete. Other errors always cause a reset. 181 * Because of source commands and .cshrc we need nested error catches. 182 */ 183 184 extern jmp_buf reslab; 185 186 #define setexit() ((void) setjmp(reslab)) 187 #define reset() longjmp(reslab, 0) 188 /* Should use structure assignment here */ 189 #define getexit(a) copy((void *)(a), (void *)reslab, sizeof reslab) 190 #define resexit(a) copy((void *)reslab, ((void *)(a)), sizeof reslab) 191 192 extern tchar *gointr; /* Label for an onintr transfer */ 193 extern void (*parintr)(); /* Parents interrupt catch */ 194 extern void (*parterm)(); /* Parents terminate catch */ 195 196 197 /* 198 * Each level of input has a buffered input structure. 199 * There are one or more blocks of buffered input for each level, 200 * exactly one if the input is seekable and tell is available. 201 * In other cases, the shell buffers enough blocks to keep all loops 202 * in the buffer. 203 */ 204 extern struct Bin { 205 off_t Bfseekp; /* Seek pointer */ 206 off_t Bfbobp; /* Seekp of beginning of buffers */ 207 off_t Bfeobp; /* Seekp of end of buffers */ 208 short Bfblocks; /* Number of buffer blocks */ 209 tchar **Bfbuf; /* The array of buffer blocks */ 210 } B; 211 212 #define fseekp B.Bfseekp 213 #define fbobp B.Bfbobp 214 #define feobp B.Bfeobp 215 #define fblocks B.Bfblocks 216 #define fbuf B.Bfbuf 217 218 #define btell() fseekp 219 220 #ifndef btell 221 extern off_t btell(void); 222 #endif 223 224 /* 225 * The shell finds commands in loops by reseeking the input 226 * For whiles, in particular, it reseeks to the beginning of the 227 * line the while was on; hence the while placement restrictions. 228 */ 229 extern off_t lineloc; 230 231 #ifdef TELL 232 extern bool cantell; /* Is current source tellable ? */ 233 #endif 234 235 /* 236 * Input lines are parsed into doubly linked circular 237 * lists of words of the following form. 238 */ 239 struct wordent { 240 tchar *word; 241 struct wordent *prev; 242 struct wordent *next; 243 }; 244 245 /* 246 * During word building, both in the initial lexical phase and 247 * when expanding $ variable substitutions, expansion by `!' and `$' 248 * must be inhibited when reading ahead in routines which are themselves 249 * processing `!' and `$' expansion or after characters such as `\' or in 250 * quotations. The following flags are passed to the getC routines 251 * telling them which of these substitutions are appropriate for the 252 * next character to be returned. 253 */ 254 #define DODOL 1 255 #define DOEXCL 2 256 #define DOALL DODOL|DOEXCL 257 258 extern tchar *lap; 259 260 /* 261 * Parser structure 262 * 263 * Each command is parsed to a tree of command structures and 264 * flags are set bottom up during this process, to be propagated down 265 * as needed during the semantics/exeuction pass (sh.sem.c). 266 */ 267 struct command { 268 short t_dtyp; /* Type of node */ 269 short t_dflg; /* Flags, e.g. FAND|... */ 270 union { 271 tchar *T_dlef; /* Input redirect word */ 272 struct command *T_dcar; /* Left part of list/pipe */ 273 } L; 274 union { 275 tchar *T_drit; /* Output redirect word */ 276 struct command *T_dcdr; /* Right part of list/pipe */ 277 } R; 278 #define t_dlef L.T_dlef 279 #define t_dcar L.T_dcar 280 #define t_drit R.T_drit 281 #define t_dcdr R.T_dcdr 282 tchar **t_dcom; /* Command/argument vector */ 283 char *cfname; /* char pathname for execv */ 284 char **cargs; /* char arg vec for execv */ 285 struct command *t_dspr; /* Pointer to ()'d subtree */ 286 short t_nice; 287 }; 288 289 #define TCOM 1 /* t_dcom <t_dlef >t_drit */ 290 #define TPAR 2 /* ( t_dspr ) <t_dlef >t_drit */ 291 #define TFIL 3 /* t_dlef | t_drit */ 292 #define TLST 4 /* t_dlef ; t_drit */ 293 #define TOR 5 /* t_dlef || t_drit */ 294 #define TAND 6 /* t_dlef && t_drit */ 295 296 #define FSAVE (FNICE|FTIME|FNOHUP) /* save these when re-doing */ 297 298 #define FAND (1<<0) /* executes in background */ 299 #define FCAT (1<<1) /* output is redirected >> */ 300 #define FPIN (1<<2) /* input is a pipe */ 301 #define FPOU (1<<3) /* output is a pipe */ 302 #define FPAR (1<<4) /* don't fork, last ()ized cmd */ 303 #define FINT (1<<5) /* should be immune from intr's */ 304 /* spare */ 305 #define FDIAG (1<<7) /* redirect unit 2 with unit 1 */ 306 #define FANY (1<<8) /* output was ! */ 307 #define FHERE (1<<9) /* input redirection is << */ 308 #define FREDO (1<<10) /* reexec aft if, repeat,... */ 309 #define FNICE (1<<11) /* t_nice is meaningful */ 310 #define FNOHUP (1<<12) /* nohup this command */ 311 #define FTIME (1<<13) /* time this command */ 312 313 /* 314 * The keywords for the parser 315 */ 316 #define ZBREAK 0 317 #define ZBRKSW 1 318 #define ZCASE 2 319 #define ZDEFAULT 3 320 #define ZELSE 4 321 #define ZEND 5 322 #define ZENDIF 6 323 #define ZENDSW 7 324 #define ZEXIT 8 325 #define ZFOREACH 9 326 #define ZGOTO 10 327 #define ZIF 11 328 #define ZLABEL 12 329 #define ZLET 13 330 #define ZSET 14 331 #define ZSWITCH 15 332 #define ZTEST 16 333 #define ZTHEN 17 334 #define ZWHILE 18 335 336 /* 337 * Structure defining the existing while/foreach loops at this 338 * source level. Loops are implemented by seeking back in the 339 * input. For foreach (fe), the word list is attached here. 340 */ 341 extern struct whyle { 342 off_t w_start; /* Point to restart loop */ 343 off_t w_end; /* End of loop (0 if unknown) */ 344 tchar **w_fe, **w_fe0; /* Current/initial wordlist for fe */ 345 tchar *w_fename; /* Name for fe */ 346 struct whyle *w_next; /* Next (more outer) loop */ 347 } *whyles; 348 349 /* 350 * Variable structure 351 * 352 * Aliases and variables are stored in AVL balanced binary trees. 353 */ 354 extern struct varent { 355 tchar **vec; /* Array of words which is the value */ 356 tchar *v_name; /* Name of variable/alias */ 357 struct varent *v_link[3]; /* The links, see below */ 358 int v_bal; /* Balance factor */ 359 } shvhed, aliases; 360 #define v_left v_link[0] 361 #define v_right v_link[1] 362 #define v_parent v_link[2] 363 364 struct varent *adrof1(); 365 #define adrof(v) adrof1(v, &shvhed) 366 #define value(v) value1(v, &shvhed) 367 368 /* 369 * MAX_VAR_LEN - maximum variable name defined by csh man page to be 128 370 */ 371 #define MAX_VAR_LEN 128 372 373 /* 374 * MAX_VREF_LEN - maximum variable reference $name[...] 375 * it can be as big as a csh word, which is 1024 376 */ 377 #define MAX_VREF_LEN 1024 378 379 380 /* 381 * The following are for interfacing redo substitution in 382 * aliases to the lexical routines. 383 */ 384 extern struct wordent *alhistp; /* Argument list (first) */ 385 extern struct wordent *alhistt; /* Node after last in arg list */ 386 extern tchar **alvec; /* The (remnants of) alias vector */ 387 388 /* 389 * Filename/command name expansion variables 390 */ 391 extern short gflag; /* After tglob -> is globbing needed? */ 392 393 /* 394 * A reasonable limit on number of arguments would seem to be 395 * the maximum number of characters in an arg list / 6. 396 * 397 * XXX: With the new VM system, NCARGS has become enormous, making 398 * it impractical to allocate arrays with NCARGS / 6 entries on 399 * the stack. The proper fix is to revamp code elsewhere (in 400 * sh.dol.c and sh.glob.c) to use a different technique for handling 401 * command line arguments. In the meantime, we simply fall back 402 * on using the old value of NCARGS. 403 */ 404 #ifdef notyet 405 #define GAVSIZ (NCARGS / 6) 406 #else /* notyet */ 407 #define GAVSIZ (10240 / 6) 408 #endif /* notyet */ 409 410 /* 411 * Variables for filename expansion 412 */ 413 extern tchar **gargv; /* Pointer to the (stack) arglist */ 414 extern long gargc; /* Number args in gargv */ 415 416 /* 417 * Variables for command expansion. 418 */ 419 extern tchar **pargv; /* Pointer to the argv list space */ 420 421 /* 422 * History list 423 * 424 * Each history list entry contains an embedded wordlist 425 * from the scanner, a number for the event, and a reference count 426 * to aid in discarding old entries. 427 * 428 * Essentially "invisible" entries are put on the history list 429 * when history substitution includes modifiers, and thrown away 430 * at the next discarding since their event numbers are very negative. 431 */ 432 extern struct Hist { 433 struct wordent Hlex; 434 int Hnum; 435 int Href; 436 struct Hist *Hnext; 437 } Histlist; 438 439 extern struct wordent paraml; /* Current lexical word list */ 440 extern int eventno; /* Next events number */ 441 442 extern tchar HIST; /* history invocation character */ 443 extern tchar HISTSUB; /* auto-substitute character */ 444 445 extern void *xalloc(size_t); 446 extern void *xcalloc(size_t, size_t); 447 extern void *xrealloc(void *, size_t); 448 extern void xfree(void *); 449 450 extern void Putchar(tchar); 451 extern void bferr(char *) __NORETURN; 452 extern void error() __NORETURN; 453 extern void exitstat(void) __NORETURN; 454 extern tchar *Dfix1(tchar *); 455 extern tchar **blkcpy(tchar **, tchar **); 456 extern tchar **blkspl(tchar **, tchar **); 457 extern char **blkspl_(char **, char **); 458 extern tchar **copyblk(tchar **); 459 extern tchar **dobackp(tchar *, bool); 460 extern tchar *domod(tchar *, int); 461 extern struct Hist *enthist(int, struct wordent *, bool); 462 extern tchar *getenv_(tchar *); 463 extern tchar *getenvs_(char *); 464 extern tchar *getwd_(tchar *); 465 extern tchar **glob(tchar **); 466 extern tchar *globone(tchar *); 467 extern tchar *index_(tchar *, tchar); 468 extern struct biltins *isbfunc(struct command *); 469 extern void pintr(void); 470 extern void pchild(void); 471 extern tchar *putn(int); 472 extern tchar *rindex_(tchar *, tchar); 473 extern tchar **saveblk(tchar **); 474 extern tchar *savestr(tchar *); 475 extern tchar *strcat_(tchar *, tchar *); 476 extern int strlen_(tchar *); 477 extern tchar *strcpy_(tchar *, tchar *); 478 extern tchar *strend(tchar *); 479 extern tchar *strip(tchar *); 480 extern tchar *strspl(tchar *, tchar *); 481 extern struct command *syntax(struct wordent *, struct wordent *, int); 482 extern tchar *value1(tchar *, struct varent *); 483 484 #define NOSTR ((tchar *) 0) 485 486 /* 487 * setname is a macro to copy the path in bname. (see sh.err.c) 488 * Here we are dynamically reallocating the bname to the new length 489 * to store the new path 490 */ 491 extern tchar *bname; 492 #define setname(a) { \ 493 bname = xrealloc(bname, (strlen_(a)+1) * sizeof (tchar)); \ 494 strcpy_(bname, a); \ 495 bname[strlen_(a)] = '\0'; \ 496 } 497 498 #ifdef VFORK 499 extern tchar *Vsav; 500 extern tchar **Vav; 501 extern tchar *Vdp; 502 #endif 503 504 extern tchar **evalvec; 505 extern tchar *evalp; 506 507 /* Conversion functions between char and tchar strings. */ 508 tchar *strtots(tchar *, char *); 509 char *tstostr(char *, tchar *); 510 511 #ifndef NULL 512 #define NULL 0 513 #endif 514 515 516 /* 517 * Xhash is an array of HSHSIZ bits (HSHSIZ / 8 chars), which are used 518 * to hash execs. If it is allocated (havhash true), then to tell 519 * whether ``name'' is (possibly) present in the i'th component 520 * of the variable path, you look at the bit in xhash indexed by 521 * hash(hashname("name"), i). This is setup automatically 522 * after .login is executed, and recomputed whenever ``path'' is 523 * changed. 524 * The two part hash function is designed to let texec() call the 525 * more expensive hashname() only once and the simple hash() several 526 * times (once for each path component checked). 527 * Byte size is assumed to be 8. 528 */ 529 #define HSHSIZ (32*1024) /* 4k bytes */ 530 #define HSHMASK (HSHSIZ - 1) 531 #define HSHMUL 243 532 533 /* 534 * The following two arrays are used for caching. xhash 535 * is for caching path variable and xhash2 is for cdpath 536 * variable. 537 */ 538 539 extern char xhash[HSHSIZ / 8]; 540 extern char xhash2[HSHSIZ / 8]; 541 #define hash(a, b) ((a) * HSHMUL + (b) & HSHMASK) 542 #define bit(h, b) ((h)[(b) >> 3] & 1 << ((b) & 7)) /* bit test */ 543 #define bis(h, b) ((h)[(b) >> 3] |= 1 << ((b) & 7)) /* bit set */ 544