2a9c11dd53
command not found. Add extra exception type and generalize error handling routines to take that exception type. Use a global variable exerrno to keep the last exec error.
846 lines
17 KiB
C
846 lines
17 KiB
C
/* $NetBSD: exec.c,v 1.19 1996/10/16 14:35:45 christos Exp $ */
|
|
|
|
/*-
|
|
* 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.
|
|
* 3. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by the University of
|
|
* California, Berkeley and its contributors.
|
|
* 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";
|
|
#else
|
|
static char rcsid[] = "$NetBSD: exec.c,v 1.19 1996/10/16 14:35:45 christos Exp $";
|
|
#endif
|
|
#endif /* not lint */
|
|
|
|
#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"
|
|
|
|
|
|
#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 __P((char *, char **, char **));
|
|
STATIC void execinterp __P((char **, char **));
|
|
STATIC void printentry __P((struct tblentry *, int));
|
|
STATIC void clearcmdentry __P((int));
|
|
STATIC struct tblentry *cmdlookup __P((char *, int));
|
|
STATIC void delete_cmd_entry __P((void));
|
|
|
|
|
|
|
|
/*
|
|
* Exec a program. Never returns. If you change this routine, you may
|
|
* have to change the find_command routine as well.
|
|
*/
|
|
|
|
void
|
|
shellexec(argv, envp, path, index)
|
|
char **argv, **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;
|
|
}
|
|
exerror(EXEXEC, "%s: %s", argv[0], errmsg(e, E_EXEC));
|
|
}
|
|
|
|
|
|
STATIC void
|
|
tryexec(cmd, argv, envp)
|
|
char *cmd;
|
|
char **argv;
|
|
char **envp;
|
|
{
|
|
int e;
|
|
#ifndef BSD
|
|
char *p;
|
|
#endif
|
|
|
|
#ifdef SYSV
|
|
do {
|
|
execve(cmd, argv, envp);
|
|
} while (errno == EINTR);
|
|
#else
|
|
execve(cmd, argv, envp);
|
|
#endif
|
|
e = errno;
|
|
if (e == ENOEXEC) {
|
|
initshellproc();
|
|
setinputfile(cmd, 0);
|
|
commandname = arg0 = savestr(argv[0]);
|
|
#ifndef BSD
|
|
pgetc(); pungetc(); /* fill up input buffer */
|
|
p = parsenextc;
|
|
if (parsenleft > 2 && p[0] == '#' && p[1] == '!') {
|
|
argv[0] = cmd;
|
|
execinterp(argv, envp);
|
|
}
|
|
#endif
|
|
setparam(argv + 1);
|
|
exraise(EXSHELLPROC);
|
|
/*NOTREACHED*/
|
|
}
|
|
errno = e;
|
|
}
|
|
|
|
|
|
#ifndef BSD
|
|
/*
|
|
* Execute an interpreter introduced by "#!", for systems where this
|
|
* feature has not been built into the kernel. If the interpreter is
|
|
* the shell, return (effectively ignoring the "#!"). If the execution
|
|
* of the interpreter fails, exit.
|
|
*
|
|
* This code peeks inside the input buffer in order to avoid actually
|
|
* reading any input. It would benefit from a rewrite.
|
|
*/
|
|
|
|
#define NEWARGS 5
|
|
|
|
STATIC void
|
|
execinterp(argv, envp)
|
|
char **argv, **envp;
|
|
{
|
|
int n;
|
|
char *inp;
|
|
char *outp;
|
|
char c;
|
|
char *p;
|
|
char **ap;
|
|
char *newargs[NEWARGS];
|
|
int i;
|
|
char **ap2;
|
|
char **new;
|
|
|
|
n = parsenleft - 2;
|
|
inp = parsenextc + 2;
|
|
ap = newargs;
|
|
for (;;) {
|
|
while (--n >= 0 && (*inp == ' ' || *inp == '\t'))
|
|
inp++;
|
|
if (n < 0)
|
|
goto bad;
|
|
if ((c = *inp++) == '\n')
|
|
break;
|
|
if (ap == &newargs[NEWARGS])
|
|
bad: error("Bad #! line");
|
|
STARTSTACKSTR(outp);
|
|
do {
|
|
STPUTC(c, outp);
|
|
} while (--n >= 0 && (c = *inp++) != ' ' && c != '\t' && c != '\n');
|
|
STPUTC('\0', outp);
|
|
n++, inp--;
|
|
*ap++ = grabstackstr(outp);
|
|
}
|
|
if (ap == newargs + 1) { /* if no args, maybe no exec is needed */
|
|
p = newargs[0];
|
|
for (;;) {
|
|
if (equal(p, "sh") || equal(p, "ash")) {
|
|
return;
|
|
}
|
|
while (*p != '/') {
|
|
if (*p == '\0')
|
|
goto break2;
|
|
p++;
|
|
}
|
|
p++;
|
|
}
|
|
break2:;
|
|
}
|
|
i = (char *)ap - (char *)newargs; /* size in bytes */
|
|
if (i == 0)
|
|
error("Bad #! line");
|
|
for (ap2 = argv ; *ap2++ != NULL ; );
|
|
new = ckmalloc(i + ((char *)ap2 - (char *)argv));
|
|
ap = newargs, ap2 = new;
|
|
while ((i -= sizeof (char **)) >= 0)
|
|
*ap2++ = *ap++;
|
|
ap = argv;
|
|
while (*ap2++ = *ap++);
|
|
shellexec(new, envp, pathval(), 0);
|
|
}
|
|
#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(path, name)
|
|
char **path;
|
|
char *name;
|
|
{
|
|
register 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(argc, argv)
|
|
int argc;
|
|
char **argv;
|
|
{
|
|
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) {
|
|
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);
|
|
printentry(cmdp, verbose);
|
|
}
|
|
flushall();
|
|
}
|
|
argptr++;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
|
|
STATIC void
|
|
printentry(cmdp, verbose)
|
|
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;
|
|
}
|
|
#ifdef 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(name, entry, printerr, path)
|
|
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;
|
|
}
|
|
while (stat(fullname, &statb) < 0) {
|
|
#ifdef SYSV
|
|
if (errno == EINTR)
|
|
continue;
|
|
#endif
|
|
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)
|
|
outfmt(out2, "here %s: %s\n", name, errmsg(e, E_EXEC));
|
|
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(name)
|
|
char *name;
|
|
{
|
|
register 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() {
|
|
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(newval)
|
|
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.
|
|
*/
|
|
|
|
STATIC void
|
|
clearcmdentry(firstchange)
|
|
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
|
|
MKINIT void deletefuncs();
|
|
|
|
SHELLPROC {
|
|
deletefuncs();
|
|
}
|
|
#endif
|
|
|
|
void
|
|
deletefuncs() {
|
|
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.
|
|
*/
|
|
|
|
struct tblentry **lastcmdentry;
|
|
|
|
|
|
STATIC struct tblentry *
|
|
cmdlookup(name, add)
|
|
char *name;
|
|
int add;
|
|
{
|
|
int hashval;
|
|
register 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() {
|
|
struct tblentry *cmdp;
|
|
|
|
INTOFF;
|
|
cmdp = *lastcmdentry;
|
|
*lastcmdentry = cmdp->next;
|
|
ckfree(cmdp);
|
|
INTON;
|
|
}
|
|
|
|
|
|
|
|
#ifdef notdef
|
|
void
|
|
getcmdentry(name, entry)
|
|
char *name;
|
|
struct cmdentry *entry;
|
|
{
|
|
struct tblentry *cmdp = cmdlookup(name, 0);
|
|
|
|
if (cmdp) {
|
|
entry->u = cmdp->param;
|
|
entry->cmdtype = cmdp->cmdtype;
|
|
} else {
|
|
entry->cmdtype = CMDUNKNOWN;
|
|
entry->u.index = 0;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
|
|
/*
|
|
* Add a new command entry, replacing any existing command entry for
|
|
* the same name.
|
|
*/
|
|
|
|
void
|
|
addcmdentry(name, entry)
|
|
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(name, func)
|
|
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(name)
|
|
char *name;
|
|
{
|
|
struct tblentry *cmdp;
|
|
|
|
if ((cmdp = cmdlookup(name, 0)) != NULL && cmdp->cmdtype == CMDFUNCTION) {
|
|
freefunc(cmdp->param.func);
|
|
delete_cmd_entry();
|
|
return (0);
|
|
}
|
|
return (1);
|
|
}
|