bin/ksh/sh.h

   1 /*      $OpenBSD: sh.h,v 1.31 2012/09/10 01:25:30 tedu Exp $    */
   2
   3 /*
   4  * Public Domain Bourne/Korn shell
   5  */
   6
   7 /* $From: sh.h,v 1.2 1994/05/19 18:32:40 michael Exp michael $ */
   8
   9 #include "config.h"     /* system and option configuration info */
  10
  11 /* Start of common headers */
  12
  13 #include <stdio.h>
  14 #include <sys/types.h>
  15 #include <setjmp.h>
  16 #include <stdbool.h>
  17 #include <stddef.h>
  18 #include <stdlib.h>
  19 #include <unistd.h>
  20 #include <string.h>
  21 #include <stdarg.h>
  22
  23 #include <errno.h>
  24 #include <fcntl.h>
  25 #include <limits.h>
  26
  27 #include <signal.h>
  28
  29 #include <paths.h>
  30
  31 /* Find a integer type that is at least 32 bits (or die) - SIZEOF_* defined
  32  * by autoconf (assumes an 8 bit byte, but I'm not concerned).
  33  * NOTE: INT32 may end up being more than 32 bits.
  34  */
  35 # define INT32  int
  36
  37 /* end of common headers */
  38
  39 /* some useful #defines */
  40 #ifdef EXTERN
  41 # define I__(i) = i
  42 #else
  43 # define I__(i)
  44 # define EXTERN extern
  45 # define EXTERN_DEFINED
  46 #endif
  47
  48 #define EXECSHELL       _PATH_BSHELL
  49 #define EXECSHELL_STR   "EXECSHELL"
  50
  51 #define NELEM(a) (sizeof(a) / sizeof((a)[0]))
  52 #define sizeofN(type, n) (sizeof(type) * (n))
  53 #define BIT(i)  (1<<(i))        /* define bit in flag */
  54
  55 /* Table flag type - needs > 16 and < 32 bits */
  56 typedef INT32 Tflag;
  57
  58 #define NUFILE  32              /* Number of user-accessible files */
  59 #define FDBASE  10              /* First file usable by Shell */
  60
  61 /* Make MAGIC a char that might be printed to make bugs more obvious, but
  62  * not a char that is used often.  Also, can't use the high bit as it causes
  63  * portability problems (calling strchr(x, 0x80|'x') is error prone).
  64  */
  65 #define MAGIC           (7)     /* prefix for *?[!{,} during expand */
  66 #define ISMAGIC(c)      ((unsigned char)(c) == MAGIC)
  67 #define NOT             '!'     /* might use ^ (ie, [!...] vs [^..]) */
  68
  69 #define LINE    2048            /* input line size */
  70 #define PATH    1024            /* pathname size (todo: PATH_MAX/pathconf()) */
  71 #define ARRAYMAX (10*1024-1)    /* max array index */
  72
  73 EXTERN  const char *kshname;    /* $0 */
  74 EXTERN  pid_t   kshpid;         /* $$, shell pid */
  75 EXTERN  pid_t   procpid;        /* pid of executing process */
  76 EXTERN  uid_t   ksheuid;        /* effective uid of shell */
  77 EXTERN  int     exstat;         /* exit status */
  78 EXTERN  int     subst_exstat;   /* exit status of last $(..)/`..` */
  79 EXTERN  const char *safe_prompt; /* safe prompt if PS1 substitution fails */
  80 EXTERN  char    username[];     /* username for \u prompt expansion */
  81
  82 /*
  83  * Area-based allocation built on malloc/free
  84  */
  85 typedef struct Area {
  86         struct link *freelist;  /* free list */
  87 } Area;
  88
  89 EXTERN  Area    aperm;          /* permanent object space */
  90 #define APERM   &aperm
  91 #define ATEMP   &e->area
  92
  93 #ifdef KSH_DEBUG
  94 # define kshdebug_init()        kshdebug_init_()
  95 # define kshdebug_printf(a)     kshdebug_printf_ a
  96 # define kshdebug_dump(a)       kshdebug_dump_ a
  97 #else /* KSH_DEBUG */
  98 # define kshdebug_init()
  99 # define kshdebug_printf(a)
 100 # define kshdebug_dump(a)
 101 #endif /* KSH_DEBUG */
 102
 103 /*
 104  * parsing & execution environment
 105  */
 106 EXTERN  struct env {
 107         short   type;                   /* environment type - see below */
 108         short   flags;                  /* EF_* */
 109         Area    area;                   /* temporary allocation area */
 110         struct  block *loc;             /* local variables and functions */
 111         short  *savefd;                 /* original redirected fd's */
 112         struct  env *oenv;              /* link to previous environment */
 113         sigjmp_buf jbuf;                /* long jump back to env creator */
 114         struct temp *temps;             /* temp files */
 115 } *e;
 116
 117 /* struct env.type values */
 118 #define E_NONE  0               /* dummy environment */
 119 #define E_PARSE 1               /* parsing command # */
 120 #define E_FUNC  2               /* executing function # */
 121 #define E_INCL  3               /* including a file via . # */
 122 #define E_EXEC  4               /* executing command tree */
 123 #define E_LOOP  5               /* executing for/while # */
 124 #define E_ERRH  6               /* general error handler # */
 125 /* # indicates env has valid jbuf (see unwind()) */
 126
 127 /* struct env.flag values */
 128 #define EF_FUNC_PARSE   BIT(0)  /* function being parsed */
 129 #define EF_BRKCONT_PASS BIT(1)  /* set if E_LOOP must pass break/continue on */
 130 #define EF_FAKE_SIGDIE  BIT(2)  /* hack to get info from unwind to quitenv */
 131
 132 /* Do breaks/continues stop at env type e? */
 133 #define STOP_BRKCONT(t) ((t) == E_NONE || (t) == E_PARSE \
 134                          || (t) == E_FUNC || (t) == E_INCL)
 135 /* Do returns stop at env type e? */
 136 #define STOP_RETURN(t)  ((t) == E_FUNC || (t) == E_INCL)
 137
 138 /* values for siglongjmp(e->jbuf, 0) */
 139 #define LRETURN 1               /* return statement */
 140 #define LEXIT   2               /* exit statement */
 141 #define LERROR  3               /* errorf() called */
 142 #define LLEAVE  4               /* untrappable exit/error */
 143 #define LINTR   5               /* ^C noticed */
 144 #define LBREAK  6               /* break statement */
 145 #define LCONTIN 7               /* continue statement */
 146 #define LSHELL  8               /* return to interactive shell() */
 147 #define LAEXPR  9               /* error in arithmetic expression */
 148
 149 /* option processing */
 150 #define OF_CMDLINE      0x01    /* command line */
 151 #define OF_SET          0x02    /* set builtin */
 152 #define OF_SPECIAL      0x04    /* a special variable changing */
 153 #define OF_INTERNAL     0x08    /* set internally by shell */
 154 #define OF_ANY          (OF_CMDLINE | OF_SET | OF_SPECIAL | OF_INTERNAL)
 155
 156 struct option {
 157     const char  *name;  /* long name of option */
 158     char        c;      /* character flag (if any) */
 159     short       flags;  /* OF_* */
 160 };
 161 extern const struct option options[];
 162
 163 /*
 164  * flags (the order of these enums MUST match the order in misc.c(options[]))
 165  */
 166 enum sh_flag {
 167         FEXPORT = 0,    /* -a: export all */
 168 #ifdef BRACE_EXPAND
 169         FBRACEEXPAND,   /* enable {} globbing */
 170 #endif
 171         FBGNICE,        /* bgnice */
 172         FCOMMAND,       /* -c: (invocation) execute specified command */
 173         FCSHHISTORY,    /* csh-style history enabled */
 174 #ifdef EMACS
 175         FEMACS,         /* emacs command editing */
 176         FEMACSUSEMETA,  /* use 8th bit as meta */
 177 #endif
 178         FERREXIT,       /* -e: quit on error */
 179 #ifdef EMACS
 180         FGMACS,         /* gmacs command editing */
 181 #endif
 182         FIGNOREEOF,     /* eof does not exit */
 183         FTALKING,       /* -i: interactive */
 184         FKEYWORD,       /* -k: name=value anywhere */
 185         FLOGIN,         /* -l: a login shell */
 186         FMARKDIRS,      /* mark dirs with / in file name completion */
 187         FMONITOR,       /* -m: job control monitoring */
 188         FNOCLOBBER,     /* -C: don't overwrite existing files */
 189         FNOEXEC,        /* -n: don't execute any commands */
 190         FNOGLOB,        /* -f: don't do file globbing */
 191         FNOHUP,         /* -H: don't kill running jobs when login shell exits */
 192         FNOLOG,         /* don't save functions in history (ignored) */
 193 #ifdef  JOBS
 194         FNOTIFY,        /* -b: asynchronous job completion notification */
 195 #endif
 196         FNOUNSET,       /* -u: using an unset var is an error */
 197         FPHYSICAL,      /* -o physical: don't do logical cd's/pwd's */
 198         FPOSIX,         /* -o posix: be posixly correct */
 199         FPRIVILEGED,    /* -p: use suid_profile */
 200         FRESTRICTED,    /* -r: restricted shell */
 201         FSH,            /* -o sh: favor sh behaviour */
 202         FSTDIN,         /* -s: (invocation) parse stdin */
 203         FTRACKALL,      /* -h: create tracked aliases for all commands */
 204         FVERBOSE,       /* -v: echo input */
 205 #ifdef VI
 206         FVI,            /* vi command editing */
 207         FVIRAW,         /* always read in raw mode (ignored) */
 208         FVISHOW8,       /* display chars with 8th bit set as is (versus M-) */
 209         FVITABCOMPLETE, /* enable tab as file name completion char */
 210         FVIESCCOMPLETE, /* enable ESC as file name completion in command mode */
 211 #endif
 212         FXTRACE,        /* -x: execution trace */
 213         FTALKING_I,     /* (internal): initial shell was interactive */
 214         FNFLAGS /* (place holder: how many flags are there) */
 215 };
 216
 217 #define Flag(f) (shell_flags[(int) (f)])
 218
 219 EXTERN  char shell_flags [FNFLAGS];
 220
 221 EXTERN  char    null [] I__("");        /* null value for variable */
 222 EXTERN  char    space [] I__(" ");
 223 EXTERN  char    newline [] I__("\n");
 224
 225 enum temp_type {
 226         TT_HEREDOC_EXP, /* expanded heredoc */
 227         TT_HIST_EDIT    /* temp file used for history editing (fc -e) */
 228 };
 229 typedef enum temp_type Temp_type;
 230 /* temp/heredoc files.  The file is removed when the struct is freed. */
 231 struct temp {
 232         struct temp     *next;
 233         struct shf      *shf;
 234         int             pid;            /* pid of process parsed here-doc */
 235         Temp_type       type;
 236         char            *name;
 237 };
 238
 239 /*
 240  * stdio and our IO routines
 241  */
 242
 243 #define shl_spare       (&shf_iob[0])   /* for c_read()/c_print() */
 244 #define shl_stdout      (&shf_iob[1])
 245 #define shl_out         (&shf_iob[2])
 246 EXTERN int shl_stdout_ok;
 247
 248 /*
 249  * trap handlers
 250  */
 251 typedef struct trap {
 252         int     signal;         /* signal number */
 253         const char *name;       /* short name */
 254         const char *mess;       /* descriptive name */
 255         char   *trap;           /* trap command */
 256         volatile sig_atomic_t set; /* trap pending */
 257         int     flags;          /* TF_* */
 258         sig_t cursig;           /* current handler (valid if TF_ORIG_* set) */
 259         sig_t shtrap;           /* shell signal handler */
 260 } Trap;
 261
 262 /* values for Trap.flags */
 263 #define TF_SHELL_USES   BIT(0)  /* shell uses signal, user can't change */
 264 #define TF_USER_SET     BIT(1)  /* user has (tried to) set trap */
 265 #define TF_ORIG_IGN     BIT(2)  /* original action was SIG_IGN */
 266 #define TF_ORIG_DFL     BIT(3)  /* original action was SIG_DFL */
 267 #define TF_EXEC_IGN     BIT(4)  /* restore SIG_IGN just before exec */
 268 #define TF_EXEC_DFL     BIT(5)  /* restore SIG_DFL just before exec */
 269 #define TF_DFL_INTR     BIT(6)  /* when received, default action is LINTR */
 270 #define TF_TTY_INTR     BIT(7)  /* tty generated signal (see j_waitj) */
 271 #define TF_CHANGED      BIT(8)  /* used by runtrap() to detect trap changes */
 272 #define TF_FATAL        BIT(9)  /* causes termination if not trapped */
 273
 274 /* values for setsig()/setexecsig() flags argument */
 275 #define SS_RESTORE_MASK 0x3     /* how to restore a signal before an exec() */
 276 #define SS_RESTORE_CURR 0       /* leave current handler in place */
 277 #define SS_RESTORE_ORIG 1       /* restore original handler */
 278 #define SS_RESTORE_DFL  2       /* restore to SIG_DFL */
 279 #define SS_RESTORE_IGN  3       /* restore to SIG_IGN */
 280 #define SS_FORCE        BIT(3)  /* set signal even if original signal ignored */
 281 #define SS_USER         BIT(4)  /* user is doing the set (ie, trap command) */
 282 #define SS_SHTRAP       BIT(5)  /* trap for internal use (CHLD,ALRM,WINCH) */
 283
 284 #define SIGEXIT_        0       /* for trap EXIT */
 285 #define SIGERR_         NSIG    /* for trap ERR */
 286
 287 EXTERN  volatile sig_atomic_t trap;     /* traps pending? */
 288 EXTERN  volatile sig_atomic_t intrsig;  /* pending trap interrupts command */
 289 EXTERN  volatile sig_atomic_t fatal_trap;/* received a fatal signal */
 290 extern  volatile sig_atomic_t got_sigwinch;
 291 extern  Trap    sigtraps[NSIG+1];
 292
 293 /*
 294  * TMOUT support
 295  */
 296 /* values for ksh_tmout_state */
 297 enum tmout_enum {
 298         TMOUT_EXECUTING = 0,    /* executing commands */
 299         TMOUT_READING,          /* waiting for input */
 300         TMOUT_LEAVING           /* have timed out */
 301 };
 302 EXTERN unsigned int ksh_tmout;
 303 EXTERN enum tmout_enum ksh_tmout_state I__(TMOUT_EXECUTING);
 304
 305 /* For "You have stopped jobs" message */
 306 EXTERN int really_exit;
 307
 308 /*
 309  * fast character classes
 310  */
 311 #define C_ALPHA  BIT(0)         /* a-z_A-Z */
 312 #define C_DIGIT  BIT(1)         /* 0-9 */
 313 #define C_LEX1   BIT(2)         /* \0 \t\n|&;<>() */
 314 #define C_VAR1   BIT(3)         /* *@#!$-? */
 315 #define C_IFSWS  BIT(4)         /* \t \n (IFS white space) */
 316 #define C_SUBOP1 BIT(5)         /* "=-+?" */
 317 #define C_SUBOP2 BIT(6)         /* "#%" */
 318 #define C_IFS    BIT(7)         /* $IFS */
 319 #define C_QUOTE  BIT(8)         /*  \n\t"#$&'()*;<>?[\`| (needing quoting) */
 320
 321 extern  short ctypes [];
 322
 323 #define ctype(c, t)     !!(ctypes[(unsigned char)(c)]&(t))
 324 #define letter(c)       ctype(c, C_ALPHA)
 325 #define digit(c)        ctype(c, C_DIGIT)
 326 #define letnum(c)       ctype(c, C_ALPHA|C_DIGIT)
 327
 328 EXTERN int ifs0 I__(' ');       /* for "$*" */
 329
 330 /* Argument parsing for built-in commands and getopts command */
 331
 332 /* Values for Getopt.flags */
 333 #define GF_ERROR        BIT(0)  /* call errorf() if there is an error */
 334 #define GF_PLUSOPT      BIT(1)  /* allow +c as an option */
 335 #define GF_NONAME       BIT(2)  /* don't print argv[0] in errors */
 336
 337 /* Values for Getopt.info */
 338 #define GI_MINUS        BIT(0)  /* an option started with -... */
 339 #define GI_PLUS         BIT(1)  /* an option started with +... */
 340 #define GI_MINUSMINUS   BIT(2)  /* arguments were ended with -- */
 341
 342 typedef struct {
 343         int             optind;
 344         int             uoptind;/* what user sees in $OPTIND */
 345         char            *optarg;
 346         int             flags;  /* see GF_* */
 347         int             info;   /* see GI_* */
 348         unsigned int    p;      /* 0 or index into argv[optind - 1] */
 349         char            buf[2]; /* for bad option OPTARG value */
 350 } Getopt;
 351
 352 EXTERN Getopt builtin_opt;      /* for shell builtin commands */
 353 EXTERN Getopt user_opt;         /* parsing state for getopts builtin command */
 354
 355 /* This for co-processes */
 356
 357 typedef INT32 Coproc_id; /* something that won't (realisticly) wrap */
 358 struct coproc {
 359         int     read;           /* pipe from co-process's stdout */
 360         int     readw;          /* other side of read (saved temporarily) */
 361         int     write;          /* pipe to co-process's stdin */
 362         Coproc_id id;           /* id of current output pipe */
 363         int     njobs;          /* number of live jobs using output pipe */
 364         void    *job;           /* 0 or job of co-process using input pipe */
 365 };
 366 EXTERN struct coproc coproc;
 367
 368 /* Used in jobs.c and by coprocess stuff in exec.c */
 369 EXTERN sigset_t         sm_default, sm_sigchld;
 370
 371 extern const char ksh_version[];
 372
 373 /* name of called builtin function (used by error functions) */
 374 EXTERN char     *builtin_argv0;
 375 EXTERN Tflag    builtin_flag;   /* flags of called builtin (SPEC_BI, etc.) */
 376
 377 /* current working directory, and size of memory allocated for same */
 378 EXTERN char     *current_wd;
 379 EXTERN int      current_wd_size;
 380
 381 #ifdef EDIT
 382 /* Minimum required space to work with on a line - if the prompt leaves less
 383  * space than this on a line, the prompt is truncated.
 384  */
 385 # define MIN_EDIT_SPACE 7
 386 /* Minimum allowed value for x_cols: 2 for prompt, 3 for " < " at end of line
 387  */
 388 # define MIN_COLS       (2 + MIN_EDIT_SPACE + 3)
 389 EXTERN  int     x_cols I__(80); /* tty columns */
 390 #else
 391 # define x_cols 80              /* for pr_menu(exec.c) */
 392 #endif
 393
 394 /* These to avoid bracket matching problems */
 395 #define OPAREN  '('
 396 #define CPAREN  ')'
 397 #define OBRACK  '['
 398 #define CBRACK  ']'
 399 #define OBRACE  '{'
 400 #define CBRACE  '}'
 401
 402 /* Determine the location of the system (common) profile */
 403 #define KSH_SYSTEM_PROFILE "/etc/profile"
 404
 405 /* Used by v_evaluate() and setstr() to control action when error occurs */
 406 #define KSH_UNWIND_ERROR        0       /* unwind the stack (longjmp) */
 407 #define KSH_RETURN_ERROR        1       /* return 1/0 for success/failure */
 408
 409 #include "shf.h"
 410 #include "table.h"
 411 #include "tree.h"
 412 #include "expand.h"
 413 #include "lex.h"
 414 #include "proto.h"
 415
 416 /* be sure not to interfere with anyone else's idea about EXTERN */
 417 #ifdef EXTERN_DEFINED
 418 # undef EXTERN_DEFINED
 419 # undef EXTERN
 420 #endif
 421 #undef I__