793 lines
		
	
	
		
			17 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			793 lines
		
	
	
		
			17 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*-
 | |
|  * Copyright (c) 1991, 1993
 | |
|  *	The Regents of the University of California.  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.
 | |
|  * 4. 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.
 | |
|  */
 | |
| 
 | |
| #ifndef lint
 | |
| #if 0
 | |
| static char sccsid[] = "@(#)exec.c	8.4 (Berkeley) 6/8/95";
 | |
| #endif
 | |
| #endif /* not lint */
 | |
| /*
 | |
| #include <sys/cdefs.h>
 | |
| __FBSDID("$FreeBSD: src/bin/sh/exec.c,v 1.24.2.1 2004/09/30 04:41:55 des Exp $");
 | |
| */
 | |
| 
 | |
| #include <sys/types.h>
 | |
| #include <sys/stat.h>
 | |
| #include <unistd.h>
 | |
| #include <fcntl.h>
 | |
| #include <errno.h>
 | |
| #include <stdlib.h>
 | |
| 
 | |
| /*
 | |
|  * When commands are first encountered, they are entered in a hash table.
 | |
|  * This ensures that a full path search will not have to be done for them
 | |
|  * on each invocation.
 | |
|  *
 | |
|  * We should investigate converting to a linear search, even though that
 | |
|  * would make the command name "hash" a misnomer.
 | |
|  */
 | |
| 
 | |
| #include "shell.h"
 | |
| #include "main.h"
 | |
| #include "nodes.h"
 | |
| #include "parser.h"
 | |
| #include "redir.h"
 | |
| #include "eval.h"
 | |
| #include "exec.h"
 | |
| #include "builtins.h"
 | |
| #include "var.h"
 | |
| #include "options.h"
 | |
| #include "input.h"
 | |
| #include "output.h"
 | |
| #include "syntax.h"
 | |
| #include "memalloc.h"
 | |
| #include "error.h"
 | |
| #include "init.h"
 | |
| #include "mystring.h"
 | |
| #include "show.h"
 | |
| #include "jobs.h"
 | |
| #include "alias.h"
 | |
| 
 | |
| 
 | |
| #define CMDTABLESIZE 31		/* should be prime */
 | |
| #define ARB 1			/* actual size determined at run time */
 | |
| 
 | |
| 
 | |
| 
 | |
| struct tblentry {
 | |
| 	struct tblentry *next;	/* next entry in hash chain */
 | |
| 	union param param;	/* definition of builtin function */
 | |
| 	short cmdtype;		/* index identifying command */
 | |
| 	char rehash;		/* if set, cd done since entry created */
 | |
| 	char cmdname[ARB];	/* name of command */
 | |
| };
 | |
| 
 | |
| 
 | |
| STATIC struct tblentry *cmdtable[CMDTABLESIZE];
 | |
| STATIC int builtinloc = -1;		/* index in path of %builtin, or -1 */
 | |
| int exerrno = 0;			/* Last exec error */
 | |
| 
 | |
| 
 | |
| STATIC void tryexec(char *, char **, char **);
 | |
| STATIC void printentry(struct tblentry *, int);
 | |
| STATIC struct tblentry *cmdlookup(char *, int);
 | |
| STATIC void delete_cmd_entry(void);
 | |
| STATIC void addcmdentry(char *, struct cmdentry *);
 | |
| 
 | |
| 
 | |
| 
 | |
| /*
 | |
|  * Exec a program.  Never returns.  If you change this routine, you may
 | |
|  * have to change the find_command routine as well.
 | |
|  */
 | |
| 
 | |
| void
 | |
| shellexec(char **argv, char **envp, char *path, int index)
 | |
| {
 | |
| 	char *cmdname;
 | |
| 	int e;
 | |
| 
 | |
| 	if (strchr(argv[0], '/') != NULL) {
 | |
| 		tryexec(argv[0], argv, envp);
 | |
| 		e = errno;
 | |
| 	} else {
 | |
| 		e = ENOENT;
 | |
| 		while ((cmdname = padvance(&path, argv[0])) != NULL) {
 | |
| 			if (--index < 0 && pathopt == NULL) {
 | |
| 				tryexec(cmdname, argv, envp);
 | |
| 				if (errno != ENOENT && errno != ENOTDIR)
 | |
| 					e = errno;
 | |
| 			}
 | |
| 			stunalloc(cmdname);
 | |
| 		}
 | |
| 	}
 | |
| 
 | |
| 	/* Map to POSIX errors */
 | |
| 	switch (e) {
 | |
| 	case EACCES:
 | |
| 		exerrno = 126;
 | |
| 		break;
 | |
| 	case ENOENT:
 | |
| 		exerrno = 127;
 | |
| 		break;
 | |
| 	default:
 | |
| 		exerrno = 2;
 | |
| 		break;
 | |
| 	}
 | |
| 	if (e == ENOENT || e == ENOTDIR)
 | |
| 		exerror(EXEXEC, "%s: not found", argv[0]);
 | |
| 	exerror(EXEXEC, "%s: %s", argv[0], strerror(e));
 | |
| }
 | |
| 
 | |
| 
 | |
| STATIC void
 | |
| tryexec(char *cmd, char **argv, char **envp)
 | |
| {
 | |
| 	int e;
 | |
| 
 | |
| 	execve(cmd, argv, envp);
 | |
| #if !__minix_vmd
 | |
| 	e = errno;
 | |
| 	if (e == ENOEXEC) {
 | |
| 		initshellproc();
 | |
| 		setinputfile(cmd, 0);
 | |
| 		commandname = arg0 = savestr(argv[0]);
 | |
| 		setparam(argv + 1);
 | |
| 		exraise(EXSHELLPROC);
 | |
| 		/*NOTREACHED*/
 | |
| 	}
 | |
| 	errno = e;
 | |
| #endif
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Do a path search.  The variable path (passed by reference) should be
 | |
|  * set to the start of the path before the first call; padvance will update
 | |
|  * this value as it proceeds.  Successive calls to padvance will return
 | |
|  * the possible path expansions in sequence.  If an option (indicated by
 | |
|  * a percent sign) appears in the path entry then the global variable
 | |
|  * pathopt will be set to point to it; otherwise pathopt will be set to
 | |
|  * NULL.
 | |
|  */
 | |
| 
 | |
| char *pathopt;
 | |
| 
 | |
| char *
 | |
| padvance(char **path, char *name)
 | |
| {
 | |
| 	char *p, *q;
 | |
| 	char *start;
 | |
| 	int len;
 | |
| 
 | |
| 	if (*path == NULL)
 | |
| 		return NULL;
 | |
| 	start = *path;
 | |
| 	for (p = start ; *p && *p != ':' && *p != '%' ; p++);
 | |
| 	len = p - start + strlen(name) + 2;	/* "2" is for '/' and '\0' */
 | |
| 	while (stackblocksize() < len)
 | |
| 		growstackblock();
 | |
| 	q = stackblock();
 | |
| 	if (p != start) {
 | |
| 		memcpy(q, start, p - start);
 | |
| 		q += p - start;
 | |
| 		*q++ = '/';
 | |
| 	}
 | |
| 	strcpy(q, name);
 | |
| 	pathopt = NULL;
 | |
| 	if (*p == '%') {
 | |
| 		pathopt = ++p;
 | |
| 		while (*p && *p != ':')  p++;
 | |
| 	}
 | |
| 	if (*p == ':')
 | |
| 		*path = p + 1;
 | |
| 	else
 | |
| 		*path = NULL;
 | |
| 	return stalloc(len);
 | |
| }
 | |
| 
 | |
| 
 | |
| 
 | |
| /*** Command hashing code ***/
 | |
| 
 | |
| 
 | |
| int
 | |
| hashcmd(int argc __unused, char **argv __unused)
 | |
| {
 | |
| 	struct tblentry **pp;
 | |
| 	struct tblentry *cmdp;
 | |
| 	int c;
 | |
| 	int verbose;
 | |
| 	struct cmdentry entry;
 | |
| 	char *name;
 | |
| 
 | |
| 	verbose = 0;
 | |
| 	while ((c = nextopt("rv")) != '\0') {
 | |
| 		if (c == 'r') {
 | |
| 			clearcmdentry(0);
 | |
| 		} else if (c == 'v') {
 | |
| 			verbose++;
 | |
| 		}
 | |
| 	}
 | |
| 	if (*argptr == NULL) {
 | |
| 		for (pp = cmdtable ; pp < &cmdtable[CMDTABLESIZE] ; pp++) {
 | |
| 			for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
 | |
| 				if (cmdp->cmdtype == CMDNORMAL)
 | |
| 					printentry(cmdp, verbose);
 | |
| 			}
 | |
| 		}
 | |
| 		return 0;
 | |
| 	}
 | |
| 	while ((name = *argptr) != NULL) {
 | |
| 		if ((cmdp = cmdlookup(name, 0)) != NULL
 | |
| 		 && (cmdp->cmdtype == CMDNORMAL
 | |
| 		     || (cmdp->cmdtype == CMDBUILTIN && builtinloc >= 0)))
 | |
| 			delete_cmd_entry();
 | |
| 		find_command(name, &entry, 1, pathval());
 | |
| 		if (verbose) {
 | |
| 			if (entry.cmdtype != CMDUNKNOWN) {	/* if no error msg */
 | |
| 				cmdp = cmdlookup(name, 0);
 | |
| 				if (cmdp != NULL)
 | |
| 					printentry(cmdp, verbose);
 | |
| 				else
 | |
| 					outfmt(&errout, "%s: not found\n", name);
 | |
| 			}
 | |
| 			flushall();
 | |
| 		}
 | |
| 		argptr++;
 | |
| 	}
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| 
 | |
| STATIC void
 | |
| printentry(struct tblentry *cmdp, int verbose)
 | |
| {
 | |
| 	int index;
 | |
| 	char *path;
 | |
| 	char *name;
 | |
| 
 | |
| 	if (cmdp->cmdtype == CMDNORMAL) {
 | |
| 		index = cmdp->param.index;
 | |
| 		path = pathval();
 | |
| 		do {
 | |
| 			name = padvance(&path, cmdp->cmdname);
 | |
| 			stunalloc(name);
 | |
| 		} while (--index >= 0);
 | |
| 		out1str(name);
 | |
| 	} else if (cmdp->cmdtype == CMDBUILTIN) {
 | |
| 		out1fmt("builtin %s", cmdp->cmdname);
 | |
| 	} else if (cmdp->cmdtype == CMDFUNCTION) {
 | |
| 		out1fmt("function %s", cmdp->cmdname);
 | |
| 		if (verbose) {
 | |
| 			INTOFF;
 | |
| 			name = commandtext(cmdp->param.func);
 | |
| 			out1c(' ');
 | |
| 			out1str(name);
 | |
| 			ckfree(name);
 | |
| 			INTON;
 | |
| 		}
 | |
| #if DEBUG
 | |
| 	} else {
 | |
| 		error("internal error: cmdtype %d", cmdp->cmdtype);
 | |
| #endif
 | |
| 	}
 | |
| 	if (cmdp->rehash)
 | |
| 		out1c('*');
 | |
| 	out1c('\n');
 | |
| }
 | |
| 
 | |
| 
 | |
| 
 | |
| /*
 | |
|  * Resolve a command name.  If you change this routine, you may have to
 | |
|  * change the shellexec routine as well.
 | |
|  */
 | |
| 
 | |
| void
 | |
| find_command(char *name, struct cmdentry *entry, int printerr, char *path)
 | |
| {
 | |
| 	struct tblentry *cmdp;
 | |
| 	int index;
 | |
| 	int prev;
 | |
| 	char *fullname;
 | |
| 	struct stat statb;
 | |
| 	int e;
 | |
| 	int i;
 | |
| 
 | |
| 	/* If name contains a slash, don't use the hash table */
 | |
| 	if (strchr(name, '/') != NULL) {
 | |
| 		entry->cmdtype = CMDNORMAL;
 | |
| 		entry->u.index = 0;
 | |
| 		return;
 | |
| 	}
 | |
| 
 | |
| 	/* If name is in the table, and not invalidated by cd, we're done */
 | |
| 	if ((cmdp = cmdlookup(name, 0)) != NULL && cmdp->rehash == 0)
 | |
| 		goto success;
 | |
| 
 | |
| 	/* If %builtin not in path, check for builtin next */
 | |
| 	if (builtinloc < 0 && (i = find_builtin(name)) >= 0) {
 | |
| 		INTOFF;
 | |
| 		cmdp = cmdlookup(name, 1);
 | |
| 		cmdp->cmdtype = CMDBUILTIN;
 | |
| 		cmdp->param.index = i;
 | |
| 		INTON;
 | |
| 		goto success;
 | |
| 	}
 | |
| 
 | |
| 	/* We have to search path. */
 | |
| 	prev = -1;		/* where to start */
 | |
| 	if (cmdp) {		/* doing a rehash */
 | |
| 		if (cmdp->cmdtype == CMDBUILTIN)
 | |
| 			prev = builtinloc;
 | |
| 		else
 | |
| 			prev = cmdp->param.index;
 | |
| 	}
 | |
| 
 | |
| 	e = ENOENT;
 | |
| 	index = -1;
 | |
| loop:
 | |
| 	while ((fullname = padvance(&path, name)) != NULL) {
 | |
| 		stunalloc(fullname);
 | |
| 		index++;
 | |
| 		if (pathopt) {
 | |
| 			if (prefix("builtin", pathopt)) {
 | |
| 				if ((i = find_builtin(name)) < 0)
 | |
| 					goto loop;
 | |
| 				INTOFF;
 | |
| 				cmdp = cmdlookup(name, 1);
 | |
| 				cmdp->cmdtype = CMDBUILTIN;
 | |
| 				cmdp->param.index = i;
 | |
| 				INTON;
 | |
| 				goto success;
 | |
| 			} else if (prefix("func", pathopt)) {
 | |
| 				/* handled below */
 | |
| 			} else {
 | |
| 				goto loop;	/* ignore unimplemented options */
 | |
| 			}
 | |
| 		}
 | |
| 		/* if rehash, don't redo absolute path names */
 | |
| 		if (fullname[0] == '/' && index <= prev) {
 | |
| 			if (index < prev)
 | |
| 				goto loop;
 | |
| 			TRACE(("searchexec \"%s\": no change\n", name));
 | |
| 			goto success;
 | |
| 		}
 | |
| 		if (stat(fullname, &statb) < 0) {
 | |
| 			if (errno != ENOENT && errno != ENOTDIR)
 | |
| 				e = errno;
 | |
| 			goto loop;
 | |
| 		}
 | |
| 		e = EACCES;	/* if we fail, this will be the error */
 | |
| 		if (!S_ISREG(statb.st_mode))
 | |
| 			goto loop;
 | |
| 		if (pathopt) {		/* this is a %func directory */
 | |
| 			stalloc(strlen(fullname) + 1);
 | |
| 			readcmdfile(fullname);
 | |
| 			if ((cmdp = cmdlookup(name, 0)) == NULL || cmdp->cmdtype != CMDFUNCTION)
 | |
| 				error("%s not defined in %s", name, fullname);
 | |
| 			stunalloc(fullname);
 | |
| 			goto success;
 | |
| 		}
 | |
| #ifdef notdef
 | |
| 		if (statb.st_uid == geteuid()) {
 | |
| 			if ((statb.st_mode & 0100) == 0)
 | |
| 				goto loop;
 | |
| 		} else if (statb.st_gid == getegid()) {
 | |
| 			if ((statb.st_mode & 010) == 0)
 | |
| 				goto loop;
 | |
| 		} else {
 | |
| 			if ((statb.st_mode & 01) == 0)
 | |
| 				goto loop;
 | |
| 		}
 | |
| #endif
 | |
| 		TRACE(("searchexec \"%s\" returns \"%s\"\n", name, fullname));
 | |
| 		INTOFF;
 | |
| 		cmdp = cmdlookup(name, 1);
 | |
| 		cmdp->cmdtype = CMDNORMAL;
 | |
| 		cmdp->param.index = index;
 | |
| 		INTON;
 | |
| 		goto success;
 | |
| 	}
 | |
| 
 | |
| 	/* We failed.  If there was an entry for this command, delete it */
 | |
| 	if (cmdp)
 | |
| 		delete_cmd_entry();
 | |
| 	if (printerr) {
 | |
| 		if (e == ENOENT || e == ENOTDIR)
 | |
| 			outfmt(out2, "%s: not found\n", name);
 | |
| 		else
 | |
| 			outfmt(out2, "%s: %s\n", name, strerror(e));
 | |
| 	}
 | |
| 	entry->cmdtype = CMDUNKNOWN;
 | |
| 	return;
 | |
| 
 | |
| success:
 | |
| 	cmdp->rehash = 0;
 | |
| 	entry->cmdtype = cmdp->cmdtype;
 | |
| 	entry->u = cmdp->param;
 | |
| }
 | |
| 
 | |
| 
 | |
| 
 | |
| /*
 | |
|  * Search the table of builtin commands.
 | |
|  */
 | |
| 
 | |
| int
 | |
| find_builtin(char *name)
 | |
| {
 | |
| 	const struct builtincmd *bp;
 | |
| 
 | |
| 	for (bp = builtincmd ; bp->name ; bp++) {
 | |
| 		if (*bp->name == *name && equal(bp->name, name))
 | |
| 			return bp->code;
 | |
| 	}
 | |
| 	return -1;
 | |
| }
 | |
| 
 | |
| 
 | |
| 
 | |
| /*
 | |
|  * Called when a cd is done.  Marks all commands so the next time they
 | |
|  * are executed they will be rehashed.
 | |
|  */
 | |
| 
 | |
| void
 | |
| hashcd(void)
 | |
| {
 | |
| 	struct tblentry **pp;
 | |
| 	struct tblentry *cmdp;
 | |
| 
 | |
| 	for (pp = cmdtable ; pp < &cmdtable[CMDTABLESIZE] ; pp++) {
 | |
| 		for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
 | |
| 			if (cmdp->cmdtype == CMDNORMAL
 | |
| 			 || (cmdp->cmdtype == CMDBUILTIN && builtinloc >= 0))
 | |
| 				cmdp->rehash = 1;
 | |
| 		}
 | |
| 	}
 | |
| }
 | |
| 
 | |
| 
 | |
| 
 | |
| /*
 | |
|  * Called before PATH is changed.  The argument is the new value of PATH;
 | |
|  * pathval() still returns the old value at this point.  Called with
 | |
|  * interrupts off.
 | |
|  */
 | |
| 
 | |
| void
 | |
| changepath(const char *newval)
 | |
| {
 | |
| 	const char *old, *new;
 | |
| 	int index;
 | |
| 	int firstchange;
 | |
| 	int bltin;
 | |
| 
 | |
| 	old = pathval();
 | |
| 	new = newval;
 | |
| 	firstchange = 9999;	/* assume no change */
 | |
| 	index = 0;
 | |
| 	bltin = -1;
 | |
| 	for (;;) {
 | |
| 		if (*old != *new) {
 | |
| 			firstchange = index;
 | |
| 			if ((*old == '\0' && *new == ':')
 | |
| 			 || (*old == ':' && *new == '\0'))
 | |
| 				firstchange++;
 | |
| 			old = new;	/* ignore subsequent differences */
 | |
| 		}
 | |
| 		if (*new == '\0')
 | |
| 			break;
 | |
| 		if (*new == '%' && bltin < 0 && prefix("builtin", new + 1))
 | |
| 			bltin = index;
 | |
| 		if (*new == ':') {
 | |
| 			index++;
 | |
| 		}
 | |
| 		new++, old++;
 | |
| 	}
 | |
| 	if (builtinloc < 0 && bltin >= 0)
 | |
| 		builtinloc = bltin;		/* zap builtins */
 | |
| 	if (builtinloc >= 0 && bltin < 0)
 | |
| 		firstchange = 0;
 | |
| 	clearcmdentry(firstchange);
 | |
| 	builtinloc = bltin;
 | |
| }
 | |
| 
 | |
| 
 | |
| /*
 | |
|  * Clear out command entries.  The argument specifies the first entry in
 | |
|  * PATH which has changed.
 | |
|  */
 | |
| 
 | |
| void
 | |
| clearcmdentry(int firstchange)
 | |
| {
 | |
| 	struct tblentry **tblp;
 | |
| 	struct tblentry **pp;
 | |
| 	struct tblentry *cmdp;
 | |
| 
 | |
| 	INTOFF;
 | |
| 	for (tblp = cmdtable ; tblp < &cmdtable[CMDTABLESIZE] ; tblp++) {
 | |
| 		pp = tblp;
 | |
| 		while ((cmdp = *pp) != NULL) {
 | |
| 			if ((cmdp->cmdtype == CMDNORMAL &&
 | |
| 			     cmdp->param.index >= firstchange)
 | |
| 			 || (cmdp->cmdtype == CMDBUILTIN &&
 | |
| 			     builtinloc >= firstchange)) {
 | |
| 				*pp = cmdp->next;
 | |
| 				ckfree(cmdp);
 | |
| 			} else {
 | |
| 				pp = &cmdp->next;
 | |
| 			}
 | |
| 		}
 | |
| 	}
 | |
| 	INTON;
 | |
| }
 | |
| 
 | |
| 
 | |
| /*
 | |
|  * Delete all functions.
 | |
|  */
 | |
| 
 | |
| #ifdef mkinit
 | |
| INCLUDE "exec.h"
 | |
| SHELLPROC {
 | |
| 	deletefuncs();
 | |
| }
 | |
| #endif
 | |
| 
 | |
| void
 | |
| deletefuncs(void)
 | |
| {
 | |
| 	struct tblentry **tblp;
 | |
| 	struct tblentry **pp;
 | |
| 	struct tblentry *cmdp;
 | |
| 
 | |
| 	INTOFF;
 | |
| 	for (tblp = cmdtable ; tblp < &cmdtable[CMDTABLESIZE] ; tblp++) {
 | |
| 		pp = tblp;
 | |
| 		while ((cmdp = *pp) != NULL) {
 | |
| 			if (cmdp->cmdtype == CMDFUNCTION) {
 | |
| 				*pp = cmdp->next;
 | |
| 				freefunc(cmdp->param.func);
 | |
| 				ckfree(cmdp);
 | |
| 			} else {
 | |
| 				pp = &cmdp->next;
 | |
| 			}
 | |
| 		}
 | |
| 	}
 | |
| 	INTON;
 | |
| }
 | |
| 
 | |
| 
 | |
| 
 | |
| /*
 | |
|  * Locate a command in the command hash table.  If "add" is nonzero,
 | |
|  * add the command to the table if it is not already present.  The
 | |
|  * variable "lastcmdentry" is set to point to the address of the link
 | |
|  * pointing to the entry, so that delete_cmd_entry can delete the
 | |
|  * entry.
 | |
|  */
 | |
| 
 | |
| STATIC struct tblentry **lastcmdentry;
 | |
| 
 | |
| 
 | |
| STATIC struct tblentry *
 | |
| cmdlookup(char *name, int add)
 | |
| {
 | |
| 	int hashval;
 | |
| 	char *p;
 | |
| 	struct tblentry *cmdp;
 | |
| 	struct tblentry **pp;
 | |
| 
 | |
| 	p = name;
 | |
| 	hashval = *p << 4;
 | |
| 	while (*p)
 | |
| 		hashval += *p++;
 | |
| 	hashval &= 0x7FFF;
 | |
| 	pp = &cmdtable[hashval % CMDTABLESIZE];
 | |
| 	for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
 | |
| 		if (equal(cmdp->cmdname, name))
 | |
| 			break;
 | |
| 		pp = &cmdp->next;
 | |
| 	}
 | |
| 	if (add && cmdp == NULL) {
 | |
| 		INTOFF;
 | |
| 		cmdp = *pp = ckmalloc(sizeof (struct tblentry) - ARB
 | |
| 					+ strlen(name) + 1);
 | |
| 		cmdp->next = NULL;
 | |
| 		cmdp->cmdtype = CMDUNKNOWN;
 | |
| 		cmdp->rehash = 0;
 | |
| 		strcpy(cmdp->cmdname, name);
 | |
| 		INTON;
 | |
| 	}
 | |
| 	lastcmdentry = pp;
 | |
| 	return cmdp;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Delete the command entry returned on the last lookup.
 | |
|  */
 | |
| 
 | |
| STATIC void
 | |
| delete_cmd_entry(void)
 | |
| {
 | |
| 	struct tblentry *cmdp;
 | |
| 
 | |
| 	INTOFF;
 | |
| 	cmdp = *lastcmdentry;
 | |
| 	*lastcmdentry = cmdp->next;
 | |
| 	ckfree(cmdp);
 | |
| 	INTON;
 | |
| }
 | |
| 
 | |
| 
 | |
| 
 | |
| /*
 | |
|  * Add a new command entry, replacing any existing command entry for
 | |
|  * the same name.
 | |
|  */
 | |
| 
 | |
| static void
 | |
| addcmdentry(char *name, struct cmdentry *entry)
 | |
| {
 | |
| 	struct tblentry *cmdp;
 | |
| 
 | |
| 	INTOFF;
 | |
| 	cmdp = cmdlookup(name, 1);
 | |
| 	if (cmdp->cmdtype == CMDFUNCTION) {
 | |
| 		freefunc(cmdp->param.func);
 | |
| 	}
 | |
| 	cmdp->cmdtype = entry->cmdtype;
 | |
| 	cmdp->param = entry->u;
 | |
| 	INTON;
 | |
| }
 | |
| 
 | |
| 
 | |
| /*
 | |
|  * Define a shell function.
 | |
|  */
 | |
| 
 | |
| void
 | |
| defun(char *name, union node *func)
 | |
| {
 | |
| 	struct cmdentry entry;
 | |
| 
 | |
| 	INTOFF;
 | |
| 	entry.cmdtype = CMDFUNCTION;
 | |
| 	entry.u.func = copyfunc(func);
 | |
| 	addcmdentry(name, &entry);
 | |
| 	INTON;
 | |
| }
 | |
| 
 | |
| 
 | |
| /*
 | |
|  * Delete a function if it exists.
 | |
|  */
 | |
| 
 | |
| int
 | |
| unsetfunc(char *name)
 | |
| {
 | |
| 	struct tblentry *cmdp;
 | |
| 
 | |
| 	if ((cmdp = cmdlookup(name, 0)) != NULL && cmdp->cmdtype == CMDFUNCTION) {
 | |
| 		freefunc(cmdp->param.func);
 | |
| 		delete_cmd_entry();
 | |
| 		return (0);
 | |
| 	}
 | |
| 	return (0);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Locate and print what a word is...
 | |
|  */
 | |
| 
 | |
| int
 | |
| typecmd(int argc, char **argv)
 | |
| {
 | |
| 	struct cmdentry entry;
 | |
| 	struct tblentry *cmdp;
 | |
| 	char **pp;
 | |
| 	struct alias *ap;
 | |
| 	int i;
 | |
| 	int error = 0;
 | |
| 	extern char *const parsekwd[];
 | |
| 
 | |
| 	for (i = 1; i < argc; i++) {
 | |
| 		out1str(argv[i]);
 | |
| 		/* First look at the keywords */
 | |
| 		for (pp = (char **)parsekwd; *pp; pp++)
 | |
| 			if (**pp == *argv[i] && equal(*pp, argv[i]))
 | |
| 				break;
 | |
| 
 | |
| 		if (*pp) {
 | |
| 			out1str(" is a shell keyword\n");
 | |
| 			continue;
 | |
| 		}
 | |
| 
 | |
| 		/* Then look at the aliases */
 | |
| 		if ((ap = lookupalias(argv[i], 1)) != NULL) {
 | |
| 			out1fmt(" is an alias for %s\n", ap->val);
 | |
| 			continue;
 | |
| 		}
 | |
| 
 | |
| 		/* Then check if it is a tracked alias */
 | |
| 		if ((cmdp = cmdlookup(argv[i], 0)) != NULL) {
 | |
| 			entry.cmdtype = cmdp->cmdtype;
 | |
| 			entry.u = cmdp->param;
 | |
| 		}
 | |
| 		else {
 | |
| 			/* Finally use brute force */
 | |
| 			find_command(argv[i], &entry, 0, pathval());
 | |
| 		}
 | |
| 
 | |
| 		switch (entry.cmdtype) {
 | |
| 		case CMDNORMAL: {
 | |
| 			if (strchr(argv[i], '/') == NULL) {
 | |
| 				char *path = pathval(), *name;
 | |
| 				int j = entry.u.index;
 | |
| 				do {
 | |
| 					name = padvance(&path, argv[i]);
 | |
| 					stunalloc(name);
 | |
| 				} while (--j >= 0);
 | |
| 				out1fmt(" is%s %s\n",
 | |
| 				    cmdp ? " a tracked alias for" : "", name);
 | |
| 			} else {
 | |
| 				if (access(argv[i], X_OK) == 0)
 | |
| 					out1fmt(" is %s\n", argv[i]);
 | |
| 				else
 | |
| 					out1fmt(": %s\n", strerror(errno));
 | |
| 			}
 | |
| 			break;
 | |
| 		}
 | |
| 		case CMDFUNCTION:
 | |
| 			out1str(" is a shell function\n");
 | |
| 			break;
 | |
| 
 | |
| 		case CMDBUILTIN:
 | |
| 			out1str(" is a shell builtin\n");
 | |
| 			break;
 | |
| 
 | |
| 		default:
 | |
| 			out1str(": not found\n");
 | |
| 			error |= 127;
 | |
| 			break;
 | |
| 		}
 | |
| 	}
 | |
| 	return error;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * $PchId: exec.c,v 1.6 2006/04/10 14:47:03 philip Exp $
 | |
|  */
 | 
