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-rw-r--r--usr/dash/eval.c1092
1 files changed, 1092 insertions, 0 deletions
diff --git a/usr/dash/eval.c b/usr/dash/eval.c
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--- /dev/null
+++ b/usr/dash/eval.c
@@ -0,0 +1,1092 @@
+/*-
+ * Copyright (c) 1993
+ * The Regents of the University of California. All rights reserved.
+ * Copyright (c) 1997-2005
+ * Herbert Xu <herbert@gondor.apana.org.au>. All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Kenneth Almquist.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <stdlib.h>
+#include <signal.h>
+#include <unistd.h>
+#include <sys/types.h>
+
+/*
+ * Evaluate a command.
+ */
+
+#include "shell.h"
+#include "nodes.h"
+#include "syntax.h"
+#include "expand.h"
+#include "parser.h"
+#include "jobs.h"
+#include "eval.h"
+#include "builtins.h"
+#include "options.h"
+#include "exec.h"
+#include "redir.h"
+#include "input.h"
+#include "output.h"
+#include "trap.h"
+#include "var.h"
+#include "memalloc.h"
+#include "error.h"
+#include "show.h"
+#include "mystring.h"
+#ifndef SMALL
+#include "myhistedit.h"
+#endif
+
+
+/* flags in argument to evaltree */
+#define EV_EXIT 01 /* exit after evaluating tree */
+#define EV_TESTED 02 /* exit status is checked; ignore -e flag */
+
+int evalskip; /* set if we are skipping commands */
+STATIC int skipcount; /* number of levels to skip */
+MKINIT int loopnest; /* current loop nesting level */
+static int funcline; /* starting line number of current function, or 0 if not in a function */
+
+
+char *commandname;
+int exitstatus; /* exit status of last command */
+int back_exitstatus; /* exit status of backquoted command */
+
+
+#if !defined(__alpha__) || (defined(__GNUC__) && __GNUC__ >= 3)
+STATIC
+#endif
+void evaltreenr(union node *, int) __attribute__ ((__noreturn__));
+STATIC void evalloop(union node *, int);
+STATIC void evalfor(union node *, int);
+STATIC void evalcase(union node *, int);
+STATIC void evalsubshell(union node *, int);
+STATIC void expredir(union node *);
+STATIC void evalpipe(union node *, int);
+#ifdef notyet
+STATIC void evalcommand(union node *, int, struct backcmd *);
+#else
+STATIC void evalcommand(union node *, int);
+#endif
+STATIC int evalbltin(const struct builtincmd *, int, char **, int);
+STATIC int evalfun(struct funcnode *, int, char **, int);
+STATIC void prehash(union node *);
+STATIC int eprintlist(struct output *, struct strlist *, int);
+STATIC int bltincmd(int, char **);
+
+
+STATIC const struct builtincmd bltin = {
+ .name = nullstr,
+ .builtin = bltincmd
+};
+
+
+/*
+ * Called to reset things after an exception.
+ */
+
+#ifdef mkinit
+INCLUDE "eval.h"
+
+RESET {
+ evalskip = 0;
+ loopnest = 0;
+}
+#endif
+
+
+
+/*
+ * The eval commmand.
+ */
+
+static int evalcmd(int argc, char **argv, int flags)
+{
+ char *p;
+ char *concat;
+ char **ap;
+
+ if (argc > 1) {
+ p = argv[1];
+ if (argc > 2) {
+ STARTSTACKSTR(concat);
+ ap = argv + 2;
+ for (;;) {
+ concat = stputs(p, concat);
+ if ((p = *ap++) == NULL)
+ break;
+ STPUTC(' ', concat);
+ }
+ STPUTC('\0', concat);
+ p = grabstackstr(concat);
+ }
+ return evalstring(p, flags & EV_TESTED);
+ }
+ return 0;
+}
+
+
+/*
+ * Execute a command or commands contained in a string.
+ */
+
+int
+evalstring(char *s, int flags)
+{
+ union node *n;
+ struct stackmark smark;
+ int status;
+
+ setinputstring(s);
+ setstackmark(&smark);
+
+ status = 0;
+ while ((n = parsecmd(0)) != NEOF) {
+ evaltree(n, flags);
+ status = exitstatus;
+ popstackmark(&smark);
+ if (evalskip)
+ break;
+ }
+ popfile();
+
+ return status;
+}
+
+
+
+/*
+ * Evaluate a parse tree. The value is left in the global variable
+ * exitstatus.
+ */
+
+void
+evaltree(union node *n, int flags)
+{
+ int checkexit = 0;
+ void (*evalfn)(union node *, int);
+ unsigned isor;
+ int status;
+ if (n == NULL) {
+ TRACE(("evaltree(NULL) called\n"));
+ goto out;
+ }
+#ifndef SMALL
+ displayhist = 1; /* show history substitutions done with fc */
+#endif
+ TRACE(("pid %d, evaltree(%p: %d, %d) called\n",
+ getpid(), n, n->type, flags));
+ switch (n->type) {
+ default:
+#ifdef DEBUG
+ out1fmt("Node type = %d\n", n->type);
+#ifndef USE_GLIBC_STDIO
+ flushout(out1);
+#endif
+ break;
+#endif
+ case NNOT:
+ evaltree(n->nnot.com, EV_TESTED);
+ status = !exitstatus;
+ goto setstatus;
+ case NREDIR:
+ errlinno = lineno = n->nredir.linno;
+ if (funcline)
+ lineno -= funcline - 1;
+ expredir(n->nredir.redirect);
+ pushredir(n->nredir.redirect);
+ status = redirectsafe(n->nredir.redirect, REDIR_PUSH);
+ if (!status) {
+ evaltree(n->nredir.n, flags & EV_TESTED);
+ status = exitstatus;
+ }
+ if (n->nredir.redirect)
+ popredir(0);
+ goto setstatus;
+ case NCMD:
+#ifdef notyet
+ if (eflag && !(flags & EV_TESTED))
+ checkexit = ~0;
+ evalcommand(n, flags, (struct backcmd *)NULL);
+ break;
+#else
+ evalfn = evalcommand;
+checkexit:
+ if (eflag && !(flags & EV_TESTED))
+ checkexit = ~0;
+ goto calleval;
+#endif
+ case NFOR:
+ evalfn = evalfor;
+ goto calleval;
+ case NWHILE:
+ case NUNTIL:
+ evalfn = evalloop;
+ goto calleval;
+ case NSUBSHELL:
+ case NBACKGND:
+ evalfn = evalsubshell;
+ goto checkexit;
+ case NPIPE:
+ evalfn = evalpipe;
+ goto checkexit;
+ case NCASE:
+ evalfn = evalcase;
+ goto calleval;
+ case NAND:
+ case NOR:
+ case NSEMI:
+#if NAND + 1 != NOR
+#error NAND + 1 != NOR
+#endif
+#if NOR + 1 != NSEMI
+#error NOR + 1 != NSEMI
+#endif
+ isor = n->type - NAND;
+ evaltree(
+ n->nbinary.ch1,
+ (flags | ((isor >> 1) - 1)) & EV_TESTED
+ );
+ if ((!exitstatus) == isor)
+ break;
+ if (!evalskip) {
+ n = n->nbinary.ch2;
+evaln:
+ evalfn = evaltree;
+calleval:
+ evalfn(n, flags);
+ break;
+ }
+ break;
+ case NIF:
+ evaltree(n->nif.test, EV_TESTED);
+ if (evalskip)
+ break;
+ if (exitstatus == 0) {
+ n = n->nif.ifpart;
+ goto evaln;
+ } else if (n->nif.elsepart) {
+ n = n->nif.elsepart;
+ goto evaln;
+ }
+ goto success;
+ case NDEFUN:
+ defun(n);
+success:
+ status = 0;
+setstatus:
+ exitstatus = status;
+ break;
+ }
+out:
+ if (checkexit & exitstatus)
+ goto exexit;
+
+ if (pendingsigs)
+ dotrap();
+
+ if (flags & EV_EXIT) {
+exexit:
+ exraise(EXEXIT);
+ }
+}
+
+
+#if !defined(__alpha__) || (defined(__GNUC__) && __GNUC__ >= 3)
+STATIC
+#endif
+void evaltreenr(union node *n, int flags)
+#ifdef HAVE_ATTRIBUTE_ALIAS
+ __attribute__ ((alias("evaltree")));
+#else
+{
+ evaltree(n, flags);
+ abort();
+}
+#endif
+
+
+STATIC void
+evalloop(union node *n, int flags)
+{
+ int status;
+
+ loopnest++;
+ status = 0;
+ flags &= EV_TESTED;
+ for (;;) {
+ int i;
+
+ evaltree(n->nbinary.ch1, EV_TESTED);
+ if (evalskip) {
+skipping: if (evalskip == SKIPCONT && --skipcount <= 0) {
+ evalskip = 0;
+ continue;
+ }
+ if (evalskip == SKIPBREAK && --skipcount <= 0)
+ evalskip = 0;
+ break;
+ }
+ i = exitstatus;
+ if (n->type != NWHILE)
+ i = !i;
+ if (i != 0)
+ break;
+ evaltree(n->nbinary.ch2, flags);
+ status = exitstatus;
+ if (evalskip)
+ goto skipping;
+ }
+ loopnest--;
+ exitstatus = status;
+}
+
+
+
+STATIC void
+evalfor(union node *n, int flags)
+{
+ struct arglist arglist;
+ union node *argp;
+ struct strlist *sp;
+ struct stackmark smark;
+
+ errlinno = lineno = n->nfor.linno;
+ if (funcline)
+ lineno -= funcline - 1;
+
+ setstackmark(&smark);
+ arglist.lastp = &arglist.list;
+ for (argp = n->nfor.args ; argp ; argp = argp->narg.next) {
+ expandarg(argp, &arglist, EXP_FULL | EXP_TILDE);
+ /* XXX */
+ if (evalskip)
+ goto out;
+ }
+ *arglist.lastp = NULL;
+
+ exitstatus = 0;
+ loopnest++;
+ flags &= EV_TESTED;
+ for (sp = arglist.list ; sp ; sp = sp->next) {
+ setvar(n->nfor.var, sp->text, 0);
+ evaltree(n->nfor.body, flags);
+ if (evalskip) {
+ if (evalskip == SKIPCONT && --skipcount <= 0) {
+ evalskip = 0;
+ continue;
+ }
+ if (evalskip == SKIPBREAK && --skipcount <= 0)
+ evalskip = 0;
+ break;
+ }
+ }
+ loopnest--;
+out:
+ popstackmark(&smark);
+}
+
+
+
+STATIC void
+evalcase(union node *n, int flags)
+{
+ union node *cp;
+ union node *patp;
+ struct arglist arglist;
+ struct stackmark smark;
+
+ errlinno = lineno = n->ncase.linno;
+ if (funcline)
+ lineno -= funcline - 1;
+
+ setstackmark(&smark);
+ arglist.lastp = &arglist.list;
+ expandarg(n->ncase.expr, &arglist, EXP_TILDE);
+ exitstatus = 0;
+ for (cp = n->ncase.cases ; cp && evalskip == 0 ; cp = cp->nclist.next) {
+ for (patp = cp->nclist.pattern ; patp ; patp = patp->narg.next) {
+ if (casematch(patp, arglist.list->text)) {
+ if (evalskip == 0) {
+ evaltree(cp->nclist.body, flags);
+ }
+ goto out;
+ }
+ }
+ }
+out:
+ popstackmark(&smark);
+}
+
+
+
+/*
+ * Kick off a subshell to evaluate a tree.
+ */
+
+STATIC void
+evalsubshell(union node *n, int flags)
+{
+ struct job *jp;
+ int backgnd = (n->type == NBACKGND);
+ int status;
+
+ errlinno = lineno = n->nredir.linno;
+ if (funcline)
+ lineno -= funcline - 1;
+
+ expredir(n->nredir.redirect);
+ if (!backgnd && flags & EV_EXIT && !have_traps())
+ goto nofork;
+ INTOFF;
+ jp = makejob(n, 1);
+ if (forkshell(jp, n, backgnd) == 0) {
+ INTON;
+ flags |= EV_EXIT;
+ if (backgnd)
+ flags &=~ EV_TESTED;
+nofork:
+ redirect(n->nredir.redirect, 0);
+ evaltreenr(n->nredir.n, flags);
+ /* never returns */
+ }
+ status = 0;
+ if (! backgnd)
+ status = waitforjob(jp);
+ exitstatus = status;
+ INTON;
+}
+
+
+
+/*
+ * Compute the names of the files in a redirection list.
+ */
+
+STATIC void
+expredir(union node *n)
+{
+ union node *redir;
+
+ for (redir = n ; redir ; redir = redir->nfile.next) {
+ struct arglist fn;
+ fn.lastp = &fn.list;
+ switch (redir->type) {
+ case NFROMTO:
+ case NFROM:
+ case NTO:
+ case NCLOBBER:
+ case NAPPEND:
+ expandarg(redir->nfile.fname, &fn, EXP_TILDE | EXP_REDIR);
+ redir->nfile.expfname = fn.list->text;
+ break;
+ case NFROMFD:
+ case NTOFD:
+ if (redir->ndup.vname) {
+ expandarg(redir->ndup.vname, &fn, EXP_FULL | EXP_TILDE);
+ fixredir(redir, fn.list->text, 1);
+ }
+ break;
+ }
+ }
+}
+
+
+
+/*
+ * Evaluate a pipeline. All the processes in the pipeline are children
+ * of the process creating the pipeline. (This differs from some versions
+ * of the shell, which make the last process in a pipeline the parent
+ * of all the rest.)
+ */
+
+STATIC void
+evalpipe(union node *n, int flags)
+{
+ struct job *jp;
+ struct nodelist *lp;
+ int pipelen;
+ int prevfd;
+ int pip[2];
+
+ TRACE(("evalpipe(0x%lx) called\n", (long)n));
+ pipelen = 0;
+ for (lp = n->npipe.cmdlist ; lp ; lp = lp->next)
+ pipelen++;
+ flags |= EV_EXIT;
+ INTOFF;
+ jp = makejob(n, pipelen);
+ prevfd = -1;
+ for (lp = n->npipe.cmdlist ; lp ; lp = lp->next) {
+ prehash(lp->n);
+ pip[1] = -1;
+ if (lp->next) {
+ if (pipe(pip) < 0) {
+ close(prevfd);
+ sh_error("Pipe call failed");
+ }
+ }
+ if (forkshell(jp, lp->n, n->npipe.backgnd) == 0) {
+ INTON;
+ if (pip[1] >= 0) {
+ close(pip[0]);
+ }
+ if (prevfd > 0) {
+ dup2(prevfd, 0);
+ close(prevfd);
+ }
+ if (pip[1] > 1) {
+ dup2(pip[1], 1);
+ close(pip[1]);
+ }
+ evaltreenr(lp->n, flags);
+ /* never returns */
+ }
+ if (prevfd >= 0)
+ close(prevfd);
+ prevfd = pip[0];
+ close(pip[1]);
+ }
+ if (n->npipe.backgnd == 0) {
+ exitstatus = waitforjob(jp);
+ TRACE(("evalpipe: job done exit status %d\n", exitstatus));
+ }
+ INTON;
+}
+
+
+
+/*
+ * Execute a command inside back quotes. If it's a builtin command, we
+ * want to save its output in a block obtained from malloc. Otherwise
+ * we fork off a subprocess and get the output of the command via a pipe.
+ * Should be called with interrupts off.
+ */
+
+void
+evalbackcmd(union node *n, struct backcmd *result)
+{
+ int pip[2];
+ struct job *jp;
+
+ result->fd = -1;
+ result->buf = NULL;
+ result->nleft = 0;
+ result->jp = NULL;
+ if (n == NULL) {
+ goto out;
+ }
+
+ if (pipe(pip) < 0)
+ sh_error("Pipe call failed");
+ jp = makejob(n, 1);
+ if (forkshell(jp, n, FORK_NOJOB) == 0) {
+ FORCEINTON;
+ close(pip[0]);
+ if (pip[1] != 1) {
+ dup2(pip[1], 1);
+ close(pip[1]);
+ }
+ ifsfree();
+ evaltreenr(n, EV_EXIT);
+ /* NOTREACHED */
+ }
+ close(pip[1]);
+ result->fd = pip[0];
+ result->jp = jp;
+
+out:
+ TRACE(("evalbackcmd done: fd=%d buf=0x%x nleft=%d jp=0x%x\n",
+ result->fd, result->buf, result->nleft, result->jp));
+}
+
+static char **
+parse_command_args(char **argv, const char **path)
+{
+ char *cp, c;
+
+ for (;;) {
+ cp = *++argv;
+ if (!cp)
+ return 0;
+ if (*cp++ != '-')
+ break;
+ if (!(c = *cp++))
+ break;
+ if (c == '-' && !*cp) {
+ if (!*++argv)
+ return 0;
+ break;
+ }
+ do {
+ switch (c) {
+ case 'p':
+ *path = defpath;
+ break;
+ default:
+ /* run 'typecmd' for other options */
+ return 0;
+ }
+ } while ((c = *cp++));
+ }
+ return argv;
+}
+
+
+
+/*
+ * Execute a simple command.
+ */
+
+STATIC void
+#ifdef notyet
+evalcommand(union node *cmd, int flags, struct backcmd *backcmd)
+#else
+evalcommand(union node *cmd, int flags)
+#endif
+{
+ struct localvar_list *localvar_stop;
+ struct redirtab *redir_stop;
+ struct stackmark smark;
+ union node *argp;
+ struct arglist arglist;
+ struct arglist varlist;
+ char **argv;
+ int argc;
+ struct strlist *sp;
+#ifdef notyet
+ int pip[2];
+#endif
+ struct cmdentry cmdentry;
+ struct job *jp;
+ char *lastarg;
+ const char *path;
+ int spclbltin;
+ int execcmd;
+ int status;
+ char **nargv;
+
+ errlinno = lineno = cmd->ncmd.linno;
+ if (funcline)
+ lineno -= funcline - 1;
+
+ /* First expand the arguments. */
+ TRACE(("evalcommand(0x%lx, %d) called\n", (long)cmd, flags));
+ setstackmark(&smark);
+ localvar_stop = pushlocalvars();
+ back_exitstatus = 0;
+
+ cmdentry.cmdtype = CMDBUILTIN;
+ cmdentry.u.cmd = &bltin;
+ varlist.lastp = &varlist.list;
+ *varlist.lastp = NULL;
+ arglist.lastp = &arglist.list;
+ *arglist.lastp = NULL;
+
+ argc = 0;
+ for (argp = cmd->ncmd.args; argp; argp = argp->narg.next) {
+ struct strlist **spp;
+
+ spp = arglist.lastp;
+ expandarg(argp, &arglist, EXP_FULL | EXP_TILDE);
+ for (sp = *spp; sp; sp = sp->next)
+ argc++;
+ }
+
+ /* Reserve one extra spot at the front for shellexec. */
+ nargv = stalloc(sizeof (char *) * (argc + 2));
+ argv = ++nargv;
+ for (sp = arglist.list ; sp ; sp = sp->next) {
+ TRACE(("evalcommand arg: %s\n", sp->text));
+ *nargv++ = sp->text;
+ }
+ *nargv = NULL;
+
+ lastarg = NULL;
+ if (iflag && funcline == 0 && argc > 0)
+ lastarg = nargv[-1];
+
+ preverrout.fd = 2;
+ expredir(cmd->ncmd.redirect);
+ redir_stop = pushredir(cmd->ncmd.redirect);
+ status = redirectsafe(cmd->ncmd.redirect, REDIR_PUSH|REDIR_SAVEFD2);
+
+ path = vpath.text;
+ for (argp = cmd->ncmd.assign; argp; argp = argp->narg.next) {
+ struct strlist **spp;
+ char *p;
+
+ spp = varlist.lastp;
+ expandarg(argp, &varlist, EXP_VARTILDE);
+
+ mklocal((*spp)->text);
+
+ /*
+ * Modify the command lookup path, if a PATH= assignment
+ * is present
+ */
+ p = (*spp)->text;
+ if (varequal(p, path))
+ path = p;
+ }
+
+ /* Print the command if xflag is set. */
+ if (xflag) {
+ struct output *out;
+ int sep;
+
+ out = &preverrout;
+ outstr(expandstr(ps4val()), out);
+ sep = 0;
+ sep = eprintlist(out, varlist.list, sep);
+ eprintlist(out, arglist.list, sep);
+ outcslow('\n', out);
+#ifdef FLUSHERR
+ flushout(out);
+#endif
+ }
+
+ execcmd = 0;
+ spclbltin = -1;
+
+ /* Now locate the command. */
+ if (argc) {
+ const char *oldpath;
+ int cmd_flag = DO_ERR;
+
+ path += 5;
+ oldpath = path;
+ for (;;) {
+ find_command(argv[0], &cmdentry, cmd_flag, path);
+ if (cmdentry.cmdtype == CMDUNKNOWN) {
+ status = 127;
+#ifdef FLUSHERR
+ flushout(&errout);
+#endif
+ goto bail;
+ }
+
+ /* implement bltin and command here */
+ if (cmdentry.cmdtype != CMDBUILTIN)
+ break;
+ if (spclbltin < 0)
+ spclbltin =
+ cmdentry.u.cmd->flags &
+ BUILTIN_SPECIAL
+ ;
+ if (cmdentry.u.cmd == EXECCMD)
+ execcmd++;
+ if (cmdentry.u.cmd != COMMANDCMD)
+ break;
+
+ path = oldpath;
+ nargv = parse_command_args(argv, &path);
+ if (!nargv)
+ break;
+ argc -= nargv - argv;
+ argv = nargv;
+ cmd_flag |= DO_NOFUNC;
+ }
+ }
+
+ if (status) {
+bail:
+ exitstatus = status;
+
+ /* We have a redirection error. */
+ if (spclbltin > 0)
+ exraise(EXERROR);
+
+ goto out;
+ }
+
+ /* Execute the command. */
+ switch (cmdentry.cmdtype) {
+ default:
+ /* Fork off a child process if necessary. */
+ if (!(flags & EV_EXIT) || have_traps()) {
+ INTOFF;
+ jp = makejob(cmd, 1);
+ if (forkshell(jp, cmd, FORK_FG) != 0) {
+ exitstatus = waitforjob(jp);
+ INTON;
+ break;
+ }
+ FORCEINTON;
+ }
+ listsetvar(varlist.list, VEXPORT|VSTACK);
+ shellexec(argv, path, cmdentry.u.index);
+ /* NOTREACHED */
+
+ case CMDBUILTIN:
+ if (spclbltin > 0 || argc == 0) {
+ poplocalvars(1);
+ if (execcmd && argc > 1)
+ listsetvar(varlist.list, VEXPORT);
+ }
+ if (evalbltin(cmdentry.u.cmd, argc, argv, flags)) {
+ int status;
+ int i;
+
+ i = exception;
+ if (i == EXEXIT)
+ goto raise;
+
+ status = (i == EXINT) ? SIGINT + 128 : 2;
+ exitstatus = status;
+
+ if (i == EXINT || spclbltin > 0) {
+raise:
+ longjmp(handler->loc, 1);
+ }
+ FORCEINTON;
+ }
+ break;
+
+ case CMDFUNCTION:
+ poplocalvars(1);
+ if (evalfun(cmdentry.u.func, argc, argv, flags))
+ goto raise;
+ break;
+ }
+
+out:
+ if (cmd->ncmd.redirect)
+ popredir(execcmd);
+ unwindredir(redir_stop);
+ unwindlocalvars(localvar_stop);
+ if (lastarg)
+ /* dsl: I think this is intended to be used to support
+ * '_' in 'vi' command mode during line editing...
+ * However I implemented that within libedit itself.
+ */
+ setvar("_", lastarg, 0);
+ popstackmark(&smark);
+}
+
+STATIC int
+evalbltin(const struct builtincmd *cmd, int argc, char **argv, int flags)
+{
+ char *volatile savecmdname;
+ struct jmploc *volatile savehandler;
+ struct jmploc jmploc;
+ int status;
+ int i;
+
+ savecmdname = commandname;
+ savehandler = handler;
+ if ((i = setjmp(jmploc.loc)))
+ goto cmddone;
+ handler = &jmploc;
+ commandname = argv[0];
+ argptr = argv + 1;
+ optptr = NULL; /* initialize nextopt */
+ if (cmd == EVALCMD)
+ status = evalcmd(argc, argv, flags);
+ else
+ status = (*cmd->builtin)(argc, argv);
+ flushall();
+ status |= outerr(out1);
+ exitstatus = status;
+cmddone:
+ freestdout();
+ commandname = savecmdname;
+ handler = savehandler;
+
+ return i;
+}
+
+STATIC int
+evalfun(struct funcnode *func, int argc, char **argv, int flags)
+{
+ volatile struct shparam saveparam;
+ struct jmploc *volatile savehandler;
+ struct jmploc jmploc;
+ int e;
+ int savefuncline;
+
+ saveparam = shellparam;
+ savefuncline = funcline;
+ savehandler = handler;
+ if ((e = setjmp(jmploc.loc))) {
+ goto funcdone;
+ }
+ INTOFF;
+ handler = &jmploc;
+ shellparam.malloc = 0;
+ func->count++;
+ funcline = func->n.ndefun.linno;
+ INTON;
+ shellparam.nparam = argc - 1;
+ shellparam.p = argv + 1;
+ shellparam.optind = 1;
+ shellparam.optoff = -1;
+ pushlocalvars();
+ evaltree(func->n.ndefun.body, flags & EV_TESTED);
+ poplocalvars(0);
+funcdone:
+ INTOFF;
+ funcline = savefuncline;
+ freefunc(func);
+ freeparam(&shellparam);
+ shellparam = saveparam;
+ handler = savehandler;
+ INTON;
+ evalskip &= ~SKIPFUNC;
+ return e;
+}
+
+
+/*
+ * Search for a command. This is called before we fork so that the
+ * location of the command will be available in the parent as well as
+ * the child. The check for "goodname" is an overly conservative
+ * check that the name will not be subject to expansion.
+ */
+
+STATIC void
+prehash(union node *n)
+{
+ struct cmdentry entry;
+
+ if (n->type == NCMD && n->ncmd.args)
+ if (goodname(n->ncmd.args->narg.text))
+ find_command(n->ncmd.args->narg.text, &entry, 0,
+ pathval());
+}
+
+
+
+/*
+ * Builtin commands. Builtin commands whose functions are closely
+ * tied to evaluation are implemented here.
+ */
+
+/*
+ * No command given.
+ */
+
+STATIC int
+bltincmd(int argc, char **argv)
+{
+ /*
+ * Preserve exitstatus of a previous possible redirection
+ * as POSIX mandates
+ */
+ return back_exitstatus;
+}
+
+
+/*
+ * Handle break and continue commands. Break, continue, and return are
+ * all handled by setting the evalskip flag. The evaluation routines
+ * above all check this flag, and if it is set they start skipping
+ * commands rather than executing them. The variable skipcount is
+ * the number of loops to break/continue, or the number of function
+ * levels to return. (The latter is always 1.) It should probably
+ * be an error to break out of more loops than exist, but it isn't
+ * in the standard shell so we don't make it one here.
+ */
+
+int
+breakcmd(int argc, char **argv)
+{
+ int n = argc > 1 ? number(argv[1]) : 1;
+
+ if (n <= 0)
+ badnum(argv[1]);
+ if (n > loopnest)
+ n = loopnest;
+ if (n > 0) {
+ evalskip = (**argv == 'c')? SKIPCONT : SKIPBREAK;
+ skipcount = n;
+ }
+ return 0;
+}
+
+
+/*
+ * The return command.
+ */
+
+int
+returncmd(int argc, char **argv)
+{
+ /*
+ * If called outside a function, do what ksh does;
+ * skip the rest of the file.
+ */
+ evalskip = SKIPFUNC;
+ return argv[1] ? number(argv[1]) : exitstatus;
+}
+
+
+int
+falsecmd(int argc, char **argv)
+{
+ return 1;
+}
+
+
+int
+truecmd(int argc, char **argv)
+{
+ return 0;
+}
+
+
+int
+execcmd(int argc, char **argv)
+{
+ if (argc > 1) {
+ iflag = 0; /* exit on error */
+ mflag = 0;
+ optschanged();
+ shellexec(argv + 1, pathval(), 0);
+ }
+ return 0;
+}
+
+
+STATIC int
+eprintlist(struct output *out, struct strlist *sp, int sep)
+{
+ while (sp) {
+ const char *p;
+
+ p = " %s";
+ p += (1 - sep);
+ sep |= 1;
+ outfmt(out, p, sp->text);
+ sp = sp->next;
+ }
+
+ return sep;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-25 21:47:17 +0000