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IABSD.fr/src/bin/ksh/c_sh.c
tobias
- bin/ksh/c_sh.c
-
/* $OpenBSD: c_sh.c,v 1.63 2018/04/09 17:53:36 tobias Exp $ */ /* * built-in Bourne commands */ #include <sys/resource.h> #include <sys/stat.h> #include <sys/time.h> #include <ctype.h> #include <errno.h> #include <fcntl.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include "sh.h" static void p_tv(struct shf *, int, struct timeval *, int, char *, char *); static void p_ts(struct shf *, int, struct timespec *, int, char *, char *); /* :, false and true */ int c_label(char **wp) { return wp[0][0] == 'f' ? 1 : 0; } int c_shift(char **wp) { struct block *l = genv->loc; int n; int64_t val; char *arg; if (ksh_getopt(wp, &builtin_opt, null) == '?') return 1; arg = wp[builtin_opt.optind]; if (arg) { evaluate(arg, &val, KSH_UNWIND_ERROR, false); n = val; } else n = 1; if (n < 0) { bi_errorf("%s: bad number", arg); return (1); } if (l->argc < n) { bi_errorf("nothing to shift"); return (1); } l->argv[n] = l->argv[0]; l->argv += n; l->argc -= n; return 0; } int c_umask(char **wp) { int i; char *cp; int symbolic = 0; mode_t old_umask; int optc; while ((optc = ksh_getopt(wp, &builtin_opt, "S")) != -1) switch (optc) { case 'S': symbolic = 1; break; case '?': return 1; } cp = wp[builtin_opt.optind]; if (cp == NULL) { old_umask = umask(0); umask(old_umask); if (symbolic) { char buf[18]; int j; old_umask = ~old_umask; cp = buf; for (i = 0; i < 3; i++) { *cp++ = "ugo"[i]; *cp++ = '='; for (j = 0; j < 3; j++) if (old_umask & (1 << (8 - (3*i + j)))) *cp++ = "rwx"[j]; *cp++ = ','; } cp[-1] = '\0'; shprintf("%s\n", buf); } else shprintf("%#3.3o\n", old_umask); } else { mode_t new_umask; if (digit(*cp)) { for (new_umask = 0; *cp >= '0' && *cp <= '7'; cp++) new_umask = new_umask * 8 + (*cp - '0'); if (*cp) { bi_errorf("bad number"); return 1; } } else { /* symbolic format */ int positions, new_val; char op; old_umask = umask(0); umask(old_umask); /* in case of error */ old_umask = ~old_umask; new_umask = old_umask; positions = 0; while (*cp) { while (*cp && strchr("augo", *cp)) switch (*cp++) { case 'a': positions |= 0111; break; case 'u': positions |= 0100; break; case 'g': positions |= 0010; break; case 'o': positions |= 0001; break; } if (!positions) positions = 0111; /* default is a */ if (!strchr("=+-", op = *cp)) break; cp++; new_val = 0; while (*cp && strchr("rwxugoXs", *cp)) switch (*cp++) { case 'r': new_val |= 04; break; case 'w': new_val |= 02; break; case 'x': new_val |= 01; break; case 'u': new_val |= old_umask >> 6; break; case 'g': new_val |= old_umask >> 3; break; case 'o': new_val |= old_umask >> 0; break; case 'X': if (old_umask & 0111) new_val |= 01; break; case 's': /* ignored */ break; } new_val = (new_val & 07) * positions; switch (op) { case '-': new_umask &= ~new_val; break; case '=': new_umask = new_val | (new_umask & ~(positions * 07)); break; case '+': new_umask |= new_val; } if (*cp == ',') { positions = 0; cp++; } else if (!strchr("=+-", *cp)) break; } if (*cp) { bi_errorf("bad mask"); return 1; } new_umask = ~new_umask; } umask(new_umask); } return 0; } int c_dot(char **wp) { char *file, *cp; char **argv; int argc; int i; int err; if (ksh_getopt(wp, &builtin_opt, null) == '?') return 1; if ((cp = wp[builtin_opt.optind]) == NULL) return 0; file = search(cp, search_path, R_OK, &err); if (file == NULL) { bi_errorf("%s: %s", cp, err ? strerror(err) : "not found"); return 1; } /* Set positional parameters? */ if (wp[builtin_opt.optind + 1]) { argv = wp + builtin_opt.optind; argv[0] = genv->loc->argv[0]; /* preserve $0 */ for (argc = 0; argv[argc + 1]; argc++) ; } else { argc = 0; argv = NULL; } i = include(file, argc, argv, 0); if (i < 0) { /* should not happen */ bi_errorf("%s: %s", cp, strerror(errno)); return 1; } return i; } int c_wait(char **wp) { int rv = 0; int sig; if (ksh_getopt(wp, &builtin_opt, null) == '?') return 1; wp += builtin_opt.optind; if (*wp == NULL) { while (waitfor(NULL, &sig) >= 0) ; rv = sig; } else { for (; *wp; wp++) rv = waitfor(*wp, &sig); if (rv < 0) rv = sig ? sig : 127; /* magic exit code: bad job-id */ } return rv; } int c_read(char **wp) { int c = 0; int expand = 1, savehist = 0; int expanding; int ecode = 0; char *cp; int fd = 0; struct shf *shf; int optc; const char *emsg; XString cs, xs; struct tbl *vp; char *xp = NULL; while ((optc = ksh_getopt(wp, &builtin_opt, "prsu,")) != -1) switch (optc) { case 'p': if ((fd = coproc_getfd(R_OK, &emsg)) < 0) { bi_errorf("-p: %s", emsg); return 1; } break; case 'r': expand = 0; break; case 's': savehist = 1; break; case 'u': if (!*(cp = builtin_opt.optarg)) fd = 0; else if ((fd = check_fd(cp, R_OK, &emsg)) < 0) { bi_errorf("-u: %s: %s", cp, emsg); return 1; } break; case '?': return 1; } wp += builtin_opt.optind; if (*wp == NULL) *--wp = "REPLY"; /* Since we can't necessarily seek backwards on non-regular files, * don't buffer them so we can't read too much. */ shf = shf_reopen(fd, SHF_RD | SHF_INTERRUPT | can_seek(fd), shl_spare); if ((cp = strchr(*wp, '?')) != NULL) { *cp = 0; if (isatty(fd)) { /* at&t ksh says it prints prompt on fd if it's open * for writing and is a tty, but it doesn't do it * (it also doesn't check the interactive flag, * as is indicated in the Kornshell book). */ shellf("%s", cp+1); } } /* If we are reading from the co-process for the first time, * make sure the other side of the pipe is closed first. This allows * the detection of eof. * * This is not compatible with at&t ksh... the fd is kept so another * coproc can be started with same output, however, this means eof * can't be detected... This is why it is closed here. * If this call is removed, remove the eof check below, too. * coproc_readw_close(fd); */ if (savehist) Xinit(xs, xp, 128, ATEMP); expanding = 0; Xinit(cs, cp, 128, ATEMP); for (; *wp != NULL; wp++) { for (cp = Xstring(cs, cp); ; ) { if (c == '\n' || c == EOF) break; while (1) { c = shf_getc(shf); if (c == '\0') continue; if (c == EOF && shf_error(shf) && shf->errno_ == EINTR) { /* Was the offending signal one that * would normally kill a process? * If so, pretend the read was killed. */ ecode = fatal_trap_check(); /* non fatal (eg, CHLD), carry on */ if (!ecode) { shf_clearerr(shf); continue; } } break; } if (savehist) { Xcheck(xs, xp); Xput(xs, xp, c); } Xcheck(cs, cp); if (expanding) { expanding = 0; if (c == '\n') { c = 0; if (Flag(FTALKING_I) && isatty(fd)) { /* set prompt in case this is * called from .profile or $ENV */ set_prompt(PS2); pprompt(prompt, 0); } } else if (c != EOF) Xput(cs, cp, c); continue; } if (expand && c == '\\') { expanding = 1; continue; } if (c == '\n' || c == EOF) break; if (ctype(c, C_IFS)) { if (Xlength(cs, cp) == 0 && ctype(c, C_IFSWS)) continue; if (wp[1]) break; } Xput(cs, cp, c); } /* strip trailing IFS white space from last variable */ if (!wp[1]) while (Xlength(cs, cp) && ctype(cp[-1], C_IFS) && ctype(cp[-1], C_IFSWS)) cp--; Xput(cs, cp, '\0'); vp = global(*wp); /* Must be done before setting export. */ if (vp->flag & RDONLY) { shf_flush(shf); bi_errorf("%s is read only", *wp); return 1; } if (Flag(FEXPORT)) typeset(*wp, EXPORT, 0, 0, 0); if (!setstr(vp, Xstring(cs, cp), KSH_RETURN_ERROR)) { shf_flush(shf); return 1; } } shf_flush(shf); if (savehist) { Xput(xs, xp, '\0'); source->line++; histsave(source->line, Xstring(xs, xp), 1); Xfree(xs, xp); } /* if this is the co-process fd, close the file descriptor * (can get eof if and only if all processes are have died, ie, * coproc.njobs is 0 and the pipe is closed). */ if (c == EOF && !ecode) coproc_read_close(fd); return ecode ? ecode : c == EOF; } int c_eval(char **wp) { struct source *s; int rv; if (ksh_getopt(wp, &builtin_opt, null) == '?') return 1; s = pushs(SWORDS, ATEMP); s->u.strv = wp + builtin_opt.optind; if (!Flag(FPOSIX)) { /* * Handle case where the command is empty due to failed * command substitution, eg, eval "$(false)". * In this case, shell() will not set/change exstat (because * compiled tree is empty), so will use this value. * subst_exstat is cleared in execute(), so should be 0 if * there were no substitutions. * * A strict reading of POSIX says we don't do this (though * it is traditionally done). [from 1003.2-1992] * 3.9.1: Simple Commands * ... If there is a command name, execution shall * continue as described in 3.9.1.1. If there * is no command name, but the command contained a command * substitution, the command shall complete with the exit * status of the last command substitution * 3.9.1.1: Command Search and Execution * ...(1)...(a) If the command name matches the name of * a special built-in utility, that special built-in * utility shall be invoked. * 3.14.5: Eval * ... If there are no arguments, or only null arguments, * eval shall return an exit status of zero. */ exstat = subst_exstat; } rv = shell(s, false); afree(s, ATEMP); return (rv); } int c_trap(char **wp) { int i; char *s; Trap *p; if (ksh_getopt(wp, &builtin_opt, null) == '?') return 1; wp += builtin_opt.optind; if (*wp == NULL) { for (p = sigtraps, i = NSIG+1; --i >= 0; p++) { if (p->trap != NULL) { shprintf("trap -- "); print_value_quoted(p->trap); shprintf(" %s\n", p->name); } } return 0; } /* * Use case sensitive lookup for first arg so the * command 'exit' isn't confused with the pseudo-signal * 'EXIT'. */ s = (gettrap(*wp, false) == NULL) ? *wp++ : NULL; /* get command */ if (s != NULL && s[0] == '-' && s[1] == '\0') s = NULL; /* set/clear traps */ while (*wp != NULL) { p = gettrap(*wp++, true); if (p == NULL) { bi_errorf("bad signal %s", wp[-1]); return 1; } settrap(p, s); } return 0; } int c_exitreturn(char **wp) { int how = LEXIT; int n; char *arg; if (ksh_getopt(wp, &builtin_opt, null) == '?') return 1; arg = wp[builtin_opt.optind]; if (arg) { if (!getn(arg, &n)) { exstat = 1; warningf(true, "%s: bad number", arg); } else exstat = n; } if (wp[0][0] == 'r') { /* return */ struct env *ep; /* need to tell if this is exit or return so trap exit will * work right (POSIX) */ for (ep = genv; ep; ep = ep->oenv) if (STOP_RETURN(ep->type)) { how = LRETURN; break; } } if (how == LEXIT && !really_exit && j_stopped_running()) { really_exit = 1; how = LSHELL; } quitenv(NULL); /* get rid of any i/o redirections */ unwind(how); /* NOTREACHED */ return 0; } int c_brkcont(char **wp) { int n, quit; struct env *ep, *last_ep = NULL; char *arg; if (ksh_getopt(wp, &builtin_opt, null) == '?') return 1; arg = wp[builtin_opt.optind]; if (!arg) n = 1; else if (!bi_getn(arg, &n)) return 1; quit = n; if (quit <= 0) { /* at&t ksh does this for non-interactive shells only - weird */ bi_errorf("%s: bad value", arg); return 1; } /* Stop at E_NONE, E_PARSE, E_FUNC, or E_INCL */ for (ep = genv; ep && !STOP_BRKCONT(ep->type); ep = ep->oenv) if (ep->type == E_LOOP) { if (--quit == 0) break; ep->flags |= EF_BRKCONT_PASS; last_ep = ep; } if (quit) { /* at&t ksh doesn't print a message - just does what it * can. We print a message 'cause it helps in debugging * scripts, but don't generate an error (ie, keep going). */ if (n == quit) { warningf(true, "%s: cannot %s", wp[0], wp[0]); return 0; } /* POSIX says if n is too big, the last enclosing loop * shall be used. Doesn't say to print an error but we * do anyway 'cause the user messed up. */ if (last_ep) last_ep->flags &= ~EF_BRKCONT_PASS; warningf(true, "%s: can only %s %d level(s)", wp[0], wp[0], n - quit); } unwind(*wp[0] == 'b' ? LBREAK : LCONTIN); /* NOTREACHED */ } int c_set(char **wp) { int argi, setargs; struct block *l = genv->loc; char **owp = wp; if (wp[1] == NULL) { static const char *const args [] = { "set", "-", NULL }; return c_typeset((char **) args); } argi = parse_args(wp, OF_SET, &setargs); if (argi < 0) return 1; /* set $# and $* */ if (setargs) { owp = wp += argi - 1; wp[0] = l->argv[0]; /* save $0 */ while (*++wp != NULL) *wp = str_save(*wp, &l->area); l->argc = wp - owp - 1; l->argv = areallocarray(NULL, l->argc+2, sizeof(char *), &l->area); for (wp = l->argv; (*wp++ = *owp++) != NULL; ) ; } /* POSIX says set exit status is 0, but old scripts that use * getopt(1), use the construct: set -- `getopt ab:c "$@"` * which assumes the exit value set will be that of the `` * (subst_exstat is cleared in execute() so that it will be 0 * if there are no command substitutions). */ return Flag(FPOSIX) ? 0 : subst_exstat; } int c_unset(char **wp) { char *id; int optc, unset_var = 1; while ((optc = ksh_getopt(wp, &builtin_opt, "fv")) != -1) switch (optc) { case 'f': unset_var = 0; break; case 'v': unset_var = 1; break; case '?': return 1; } wp += builtin_opt.optind; for (; (id = *wp) != NULL; wp++) if (unset_var) { /* unset variable */ struct tbl *vp = global(id); if ((vp->flag&RDONLY)) { bi_errorf("%s is read only", vp->name); return 1; } unset(vp, strchr(id, '[') ? 1 : 0); } else { /* unset function */ define(id, NULL); } return 0; } static void p_tv(struct shf *shf, int posix, struct timeval *tv, int width, char *prefix, char *suffix) { if (posix) shf_fprintf(shf, "%s%*lld.%02ld%s", prefix ? prefix : "", width, (long long)tv->tv_sec, tv->tv_usec / 10000, suffix); else shf_fprintf(shf, "%s%*lldm%02lld.%02lds%s", prefix ? prefix : "", width, (long long)tv->tv_sec / 60, (long long)tv->tv_sec % 60, tv->tv_usec / 10000, suffix); } static void p_ts(struct shf *shf, int posix, struct timespec *ts, int width, char *prefix, char *suffix) { if (posix) shf_fprintf(shf, "%s%*lld.%02ld%s", prefix ? prefix : "", width, (long long)ts->tv_sec, ts->tv_nsec / 10000000, suffix); else shf_fprintf(shf, "%s%*lldm%02lld.%02lds%s", prefix ? prefix : "", width, (long long)ts->tv_sec / 60, (long long)ts->tv_sec % 60, ts->tv_nsec / 10000000, suffix); } int c_times(char **wp) { struct rusage usage; (void) getrusage(RUSAGE_SELF, &usage); p_tv(shl_stdout, 0, &usage.ru_utime, 0, NULL, " "); p_tv(shl_stdout, 0, &usage.ru_stime, 0, NULL, "\n"); (void) getrusage(RUSAGE_CHILDREN, &usage); p_tv(shl_stdout, 0, &usage.ru_utime, 0, NULL, " "); p_tv(shl_stdout, 0, &usage.ru_stime, 0, NULL, "\n"); return 0; } /* * time pipeline (really a statement, not a built-in command) */ int timex(struct op *t, int f, volatile int *xerrok) { #define TF_NOARGS BIT(0) #define TF_NOREAL BIT(1) /* don't report real time */ #define TF_POSIX BIT(2) /* report in posix format */ int rv = 0; struct rusage ru0, ru1, cru0, cru1; struct timeval usrtime, systime; struct timespec ts0, ts1, ts2; int tf = 0; extern struct timeval j_usrtime, j_systime; /* computed by j_wait */ clock_gettime(CLOCK_MONOTONIC, &ts0); getrusage(RUSAGE_SELF, &ru0); getrusage(RUSAGE_CHILDREN, &cru0); if (t->left) { /* * Two ways of getting cpu usage of a command: just use t0 * and t1 (which will get cpu usage from other jobs that * finish while we are executing t->left), or get the * cpu usage of t->left. at&t ksh does the former, while * pdksh tries to do the later (the j_usrtime hack doesn't * really work as it only counts the last job). */ timerclear(&j_usrtime); timerclear(&j_systime); rv = execute(t->left, f | XTIME, xerrok); if (t->left->type == TCOM) tf |= t->left->str[0]; clock_gettime(CLOCK_MONOTONIC, &ts1); getrusage(RUSAGE_SELF, &ru1); getrusage(RUSAGE_CHILDREN, &cru1); } else tf = TF_NOARGS; if (tf & TF_NOARGS) { /* ksh93 - report shell times (shell+kids) */ tf |= TF_NOREAL; timeradd(&ru0.ru_utime, &cru0.ru_utime, &usrtime); timeradd(&ru0.ru_stime, &cru0.ru_stime, &systime); } else { timersub(&ru1.ru_utime, &ru0.ru_utime, &usrtime); timeradd(&usrtime, &j_usrtime, &usrtime); timersub(&ru1.ru_stime, &ru0.ru_stime, &systime); timeradd(&systime, &j_systime, &systime); } if (!(tf & TF_NOREAL)) { timespecsub(&ts1, &ts0, &ts2); if (tf & TF_POSIX) p_ts(shl_out, 1, &ts2, 5, "real ", "\n"); else p_ts(shl_out, 0, &ts2, 5, NULL, " real "); } if (tf & TF_POSIX) p_tv(shl_out, 1, &usrtime, 5, "user ", "\n"); else p_tv(shl_out, 0, &usrtime, 5, NULL, " user "); if (tf & TF_POSIX) p_tv(shl_out, 1, &systime, 5, "sys ", "\n"); else p_tv(shl_out, 0, &systime, 5, NULL, " system\n"); shf_flush(shl_out); return rv; } void timex_hook(struct op *t, char **volatile *app) { char **wp = *app; int optc; int i, j; Getopt opt; ksh_getopt_reset(&opt, 0); opt.optind = 0; /* start at the start */ while ((optc = ksh_getopt(wp, &opt, ":p")) != -1) switch (optc) { case 'p': t->str[0] |= TF_POSIX; break; case '?': errorf("time: -%s unknown option", opt.optarg); case ':': errorf("time: -%s requires an argument", opt.optarg); } /* Copy command words down over options. */ if (opt.optind != 0) { for (i = 0; i < opt.optind; i++) afree(wp[i], ATEMP); for (i = 0, j = opt.optind; (wp[i] = wp[j]); i++, j++) ; } if (!wp[0]) t->str[0] |= TF_NOARGS; *app = wp; } /* exec with no args - args case is taken care of in comexec() */ int c_exec(char **wp) { int i; /* make sure redirects stay in place */ if (genv->savefd != NULL) { for (i = 0; i < NUFILE; i++) { if (genv->savefd[i] > 0) close(genv->savefd[i]); /* * For ksh keep anything > 2 private, * for sh, let them be (POSIX says what * happens is unspecified and the bourne shell * keeps them open). */ if (!Flag(FSH) && i > 2 && genv->savefd[i]) fcntl(i, F_SETFD, FD_CLOEXEC); } genv->savefd = NULL; } return 0; } static int c_suspend(char **wp) { if (wp[1] != NULL) { bi_errorf("too many arguments"); return 1; } if (Flag(FLOGIN)) { /* Can't suspend an orphaned process group. */ pid_t parent = getppid(); if (getpgid(parent) == getpgid(0) || getsid(parent) != getsid(0)) { bi_errorf("can't suspend a login shell"); return 1; } } j_suspend(); return 0; } /* dummy function, special case in comexec() */ int c_builtin(char **wp) { return 0; } extern int c_test(char **wp); /* in c_test.c */ extern int c_ulimit(char **wp); /* in c_ulimit.c */ /* A leading = means assignments before command are kept; * a leading * means a POSIX special builtin; * a leading + means a POSIX regular builtin * (* and + should not be combined). */ const struct builtin shbuiltins [] = { {"*=.", c_dot}, {"*=:", c_label}, {"[", c_test}, {"*=break", c_brkcont}, {"=builtin", c_builtin}, {"*=continue", c_brkcont}, {"*=eval", c_eval}, {"*=exec", c_exec}, {"*=exit", c_exitreturn}, {"+false", c_label}, {"*=return", c_exitreturn}, {"*=set", c_set}, {"*=shift", c_shift}, {"*=times", c_times}, {"*=trap", c_trap}, {"+=wait", c_wait}, {"+read", c_read}, {"test", c_test}, {"+true", c_label}, {"ulimit", c_ulimit}, {"+umask", c_umask}, {"*=unset", c_unset}, {"suspend", c_suspend}, {NULL, NULL} };