rsalz@uunet.uu.net (Rich Salz) (05/31/89)
Submitted-by: ka@june.cs.washington.edu (Kenneth Almquist)
Posting-number: Volume 19, Issue 3
Archive-name: ash/part03
# This is part 3 of ash. To unpack, feed it into the shell (not csh).
# The ash distribution consists of eight pieces. Be sure you get them all.
# After you unpack everything, read the file README.
echo extracting exec.c
cat > exec.c <<\EOF
/*
* 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 <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include "myerrno.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; /* index in path of %builtin, or -1 */
#ifdef __STDC__
STATIC void tryexec(char *, char **, char **);
STATIC void execinterp(char **, char **);
STATIC void printentry(struct tblentry *);
STATIC void clearcmdentry(int);
STATIC struct tblentry *cmdlookup(char *, int);
STATIC void delete_cmd_entry(void);
#else
STATIC void tryexec();
STATIC void execinterp();
STATIC void printentry();
STATIC void clearcmdentry();
STATIC struct tblentry *cmdlookup();
STATIC void delete_cmd_entry();
#endif
/*
* 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;
{
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);
}
}
error2(argv[0], errmsg(e, E_EXEC));
}
STATIC void
tryexec(cmd, argv, envp)
char *cmd;
char **argv;
char **envp;
{
int e;
char *p;
#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);
raise(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) {
bcopy(start, q, 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 ***/
hashcmd(argc, argv) char **argv; {
struct tblentry **pp;
struct tblentry *cmdp;
int c;
int verbose;
struct cmdentry entry;
char *name;
if (argc <= 1) {
for (pp = cmdtable ; pp < &cmdtable[CMDTABLESIZE] ; pp++) {
for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) {
printentry(cmdp);
}
}
return 0;
}
verbose = 0;
while ((c = nextopt("rv")) != '\0') {
if (c == 'r') {
clearcmdentry(0);
} else if (c == 'v') {
verbose++;
}
}
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);
if (verbose) {
if (entry.cmdtype != CMDUNKNOWN) { /* if no error msg */
cmdp = cmdlookup(name, 0);
printentry(cmdp);
}
flushall();
}
argptr++;
}
return 0;
}
STATIC void
printentry(cmdp)
struct tblentry *cmdp;
{
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);
#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)
char *name;
struct cmdentry *entry;
{
struct tblentry *cmdp;
int index;
int prev;
char *path;
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;
}
path = pathval();
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 ((statb.st_mode & S_IFMT) != S_IFREG)
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;
}
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;
}
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, "%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;
{
const register 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)
char *newval;
{
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) {
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 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.
*/
void
unsetfunc(name)
char *name;
{
struct tblentry *cmdp;
if ((cmdp = cmdlookup(name, 0)) != NULL && cmdp->cmdtype == CMDFUNCTION) {
freefunc(cmdp->param.func);
delete_cmd_entry();
}
}
EOF
if test `wc -c < exec.c` -ne 16808
then echo 'exec.c is the wrong size'
fi
echo extracting expand.h
cat > expand.h <<\EOF
/*
* Copyright (C) 1989 by Kenneth Almquist. All rights reserved.
* This file is part of ash, which is distributed under the terms specified
* by the Ash General Public License. See the file named LICENSE.
*/
struct strlist {
struct strlist *next;
char *text;
};
struct arglist {
struct strlist *list;
struct strlist **lastp;
};
#ifdef __STDC__
void expandarg(union node *, struct arglist *, int);
void expandhere(union node *, int);
int patmatch(char *, char *);
void rmescapes(char *);
int casematch(union node *, char *);
#else
void expandarg();
void expandhere();
int patmatch();
void rmescapes();
int casematch();
#endif
EOF
if test `wc -c < expand.h` -ne 662
then echo 'expand.h is the wrong size'
fi
echo extracting expand.c
cat > expand.c <<\EOF
/*
* Routines to expand arguments to commands. We have to deal with
* backquotes, shell variables, and file metacharacters.
*
* Copyright (C) 1989 by Kenneth Almquist. All rights reserved.
* This file is part of ash, which is distributed under the terms specified
* by the Ash General Public License. See the file named LICENSE.
*/
#include "shell.h"
#include "main.h"
#include "nodes.h"
#include "eval.h"
#include "expand.h"
#include "syntax.h"
#include "parser.h"
#include "jobs.h"
#include "options.h"
#include "var.h"
#include "input.h"
#include "output.h"
#include "memalloc.h"
#include "error.h"
#include "mystring.h"
#include <sys/types.h>
#include <sys/stat.h>
#include "mydirent.h"
#include "myerrno.h"
/*
* Structure specifying which parts of the string should be searched
* for IFS characters.
*/
struct ifsregion {
struct ifsregion *next; /* next region in list */
int begoff; /* offset of start of region */
int endoff; /* offset of end of region */
int nulonly; /* search for nul bytes only */
};
char *expdest; /* output of current string */
struct nodelist *argbackq; /* list of back quote expressions */
struct ifsregion ifsfirst; /* first struct in list of ifs regions */
struct ifsregion *ifslastp; /* last struct in list */
struct arglist exparg; /* holds expanded arg list */
#if UDIR
/*
* Set if the last argument processed had /u/logname expanded. This
* variable is read by the cd command.
*/
int didudir;
#endif
#ifdef __STDC__
STATIC void argstr(char *, int);
STATIC void expbackq(union node *, int, int);
STATIC char *evalvar(char *, int);
STATIC int varisset(int);
STATIC void varvalue(int, int, int);
STATIC void recordregion(int, int, int);
STATIC void ifsbreakup(char *, struct arglist *);
STATIC void expandmeta(struct strlist *);
STATIC void expmeta(char *, char *);
STATIC void addfname(char *);
STATIC struct strlist *expsort(struct strlist *);
STATIC struct strlist *msort(struct strlist *, int);
STATIC int pmatch(char *, char *);
#else
STATIC void argstr();
STATIC void expbackq();
STATIC char *evalvar();
STATIC int varisset();
STATIC void varvalue();
STATIC void recordregion();
STATIC void ifsbreakup();
STATIC void expandmeta();
STATIC void expmeta();
STATIC void addfname();
STATIC struct strlist *expsort();
STATIC struct strlist *msort();
STATIC int pmatch();
#endif
#if UDIR
#ifdef __STDC__
STATIC char *expudir(char *);
#else
STATIC char *expudir();
#endif
#endif /* UDIR */
/*
* Expand shell variables and backquotes inside a here document.
*/
void
expandhere(arg, fd)
union node *arg; /* the document */
int fd; /* where to write the expanded version */
{
herefd = fd;
expandarg(arg, (struct arglist *)NULL, 0);
xwrite(fd, stackblock(), expdest - stackblock());
}
/*
* Perform variable substitution and command substitution on an argument,
* placing the resulting list of arguments in arglist. If full is true,
* perform splitting and file name expansion. When arglist is NULL, perform
* here document expansion.
*/
void
expandarg(arg, arglist, full)
union node *arg;
struct arglist *arglist;
{
struct strlist *sp;
char *p;
#if UDIR
didudir = 0;
#endif
argbackq = arg->narg.backquote;
STARTSTACKSTR(expdest);
ifsfirst.next = NULL;
ifslastp = NULL;
argstr(arg->narg.text, full);
if (arglist == NULL)
return; /* here document expanded */
STPUTC('\0', expdest);
p = grabstackstr(expdest);
exparg.lastp = &exparg.list;
if (full) {
ifsbreakup(p, &exparg);
*exparg.lastp = NULL;
exparg.lastp = &exparg.list;
expandmeta(exparg.list);
} else {
sp = (struct strlist *)stalloc(sizeof (struct strlist));
sp->text = p;
*exparg.lastp = sp;
exparg.lastp = &sp->next;
}
while (ifsfirst.next != NULL) {
struct ifsregion *ifsp;
INTOFF;
ifsp = ifsfirst.next->next;
ckfree(ifsfirst.next);
ifsfirst.next = ifsp;
INTON;
}
*exparg.lastp = NULL;
if (exparg.list) {
*arglist->lastp = exparg.list;
arglist->lastp = exparg.lastp;
}
}
/*
* Perform variable and command substitution. If full is set, output CTLESC
* characters to allow for further processing. If full is not set, treat
* $@ like $* since no splitting will be performed.
*/
STATIC void
argstr(p, full)
register char *p;
{
char c;
for (;;) {
switch (c = *p++) {
case '\0':
case CTLENDVAR:
goto breakloop;
case CTLESC:
if (full)
STPUTC(c, expdest);
c = *p++;
STPUTC(c, expdest);
break;
case CTLVAR:
p = evalvar(p, full);
break;
case CTLBACKQ:
case CTLBACKQ|CTLQUOTE:
expbackq(argbackq->n, c & CTLQUOTE, full);
argbackq = argbackq->next;
break;
default:
STPUTC(c, expdest);
}
}
breakloop:;
}
/*
* Expand stuff in backwards quotes.
*/
STATIC void
expbackq(cmd, quoted, full)
union node *cmd;
{
struct backcmd in;
int i;
char buf[128];
char *p;
char *dest = expdest;
struct ifsregion saveifs, *savelastp;
struct nodelist *saveargbackq;
char lastc;
int startloc = dest - stackblock();
char const *syntax = quoted? DQSYNTAX : BASESYNTAX;
int saveherefd;
INTOFF;
saveifs = ifsfirst;
savelastp = ifslastp;
saveargbackq = argbackq;
saveherefd = herefd;
herefd = -1;
p = grabstackstr(dest);
evalbackcmd(cmd, &in);
ungrabstackstr(p, dest);
ifsfirst = saveifs;
ifslastp = savelastp;
argbackq = saveargbackq;
herefd = saveherefd;
p = in.buf;
lastc = '\0';
for (;;) {
if (--in.nleft < 0) {
if (in.fd < 0)
break;
while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR);
TRACE(("expbackq: read returns %d\n", i));
if (i <= 0)
break;
p = buf;
in.nleft = i - 1;
}
lastc = *p++;
if (lastc != '\0') {
if (full && syntax[lastc] == CCTL)
STPUTC(CTLESC, dest);
STPUTC(lastc, dest);
}
}
if (lastc == '\n') {
STUNPUTC(dest);
}
if (in.fd >= 0)
close(in.fd);
if (in.buf)
ckfree(in.buf);
if (in.jp)
waitforjob(in.jp);
if (quoted == 0)
recordregion(startloc, dest - stackblock(), 0);
TRACE(("evalbackq: size=%d: \"%.*s\"\n",
(dest - stackblock()) - startloc,
(dest - stackblock()) - startloc,
stackblock() + startloc));
expdest = dest;
INTON;
}
/*
* Expand a variable, and return a pointer to the next character in the
* input string.
*/
STATIC char *
evalvar(p, full)
char *p;
{
int subtype;
int flags;
char *var;
char *val;
int c;
int set;
int special;
int startloc;
flags = *p++;
subtype = flags & VSTYPE;
var = p;
special = 0;
if (! is_name(*p))
special = 1;
p = strchr(p, '=') + 1;
again: /* jump here after setting a variable with ${var=text} */
if (special) {
set = varisset(*var);
val = NULL;
} else {
val = lookupvar(var);
if (val == NULL || (flags & VSNUL) && val[0] == '\0') {
val = NULL;
set = 0;
} else
set = 1;
}
startloc = expdest - stackblock();
if (set && subtype != VSPLUS) {
/* insert the value of the variable */
if (special) {
varvalue(*var, flags & VSQUOTE, full);
} else {
char const *syntax = (flags & VSQUOTE)? DQSYNTAX : BASESYNTAX;
while (*val) {
if (full && syntax[*val] == CCTL)
STPUTC(CTLESC, expdest);
STPUTC(*val++, expdest);
}
}
}
if (subtype == VSPLUS)
set = ! set;
if (((flags & VSQUOTE) == 0 || (*var == '@' && shellparam.nparam != 1))
&& (set || subtype == VSNORMAL))
recordregion(startloc, expdest - stackblock(), flags & VSQUOTE);
if (! set && subtype != VSNORMAL) {
if (subtype == VSPLUS || subtype == VSMINUS) {
argstr(p, full);
} else {
char *startp;
int saveherefd = herefd;
herefd = -1;
argstr(p, 0);
STACKSTRNUL(expdest);
herefd = saveherefd;
startp = stackblock() + startloc;
if (subtype == VSASSIGN) {
setvar(var, startp, 0);
STADJUST(startp - expdest, expdest);
flags &=~ VSNUL;
goto again;
}
/* subtype == VSQUESTION */
if (*p != CTLENDVAR) {
outfmt(&errout, "%s\n", startp);
error((char *)NULL);
}
error("%.*s: parameter %snot set", p - var - 1,
var, (flags & VSNUL)? "null or " : nullstr);
}
}
if (subtype != VSNORMAL) { /* skip to end of alternative */
int nesting = 1;
for (;;) {
if ((c = *p++) == CTLESC)
p++;
else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) {
if (set)
argbackq = argbackq->next;
} else if (c == CTLVAR) {
if ((*p++ & VSTYPE) != VSNORMAL)
nesting++;
} else if (c == CTLENDVAR) {
if (--nesting == 0)
break;
}
}
}
return p;
}
/*
* Test whether a specialized variable is set.
*/
STATIC int
varisset(name)
char name;
{
char **ap;
if (name == '!') {
if (backgndpid == -1)
return 0;
} else if (name == '@' || name == '*') {
if (*shellparam.p == NULL)
return 0;
} else if ((unsigned)(name -= '1') <= '9' - '1') {
ap = shellparam.p;
do {
if (*ap++ == NULL)
return 0;
} while (--name >= 0);
}
return 1;
}
/*
* Add the value of a specialized variable to the stack string.
*/
STATIC void
varvalue(name, quoted, allow_split)
char name;
{
int num;
char temp[32];
char *p;
int i;
extern int exitstatus;
char sep;
char **ap;
char const *syntax;
switch (name) {
case '$':
num = rootpid;
goto numvar;
case '?':
num = exitstatus;
goto numvar;
case '#':
num = shellparam.nparam;
goto numvar;
case '!':
num = backgndpid;
numvar:
p = temp + 31;
temp[31] = '\0';
do {
*--p = num % 10 + '0';
} while ((num /= 10) != 0);
while (*p)
STPUTC(*p++, expdest);
break;
case '-':
for (i = 0 ; optchar[i] ; i++) {
if (optval[i])
STPUTC(optchar[i], expdest);
}
break;
case '@':
if (allow_split) {
sep = '\0';
goto allargs;
}
/* fall through */
case '*':
sep = ' ';
allargs:
syntax = quoted? DQSYNTAX : BASESYNTAX;
for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
/* should insert CTLESC characters */
while (*p) {
if (syntax[*p] == CCTL)
STPUTC(CTLESC, expdest);
STPUTC(*p++, expdest);
}
if (*ap)
STPUTC(sep, expdest);
}
break;
case '0':
p = arg0;
string:
syntax = quoted? DQSYNTAX : BASESYNTAX;
while (*p) {
if (syntax[*p] == CCTL)
STPUTC(CTLESC, expdest);
STPUTC(*p++, expdest);
}
break;
default:
if ((unsigned)(name -= '1') <= '9' - '1') {
p = shellparam.p[name];
goto string;
}
break;
}
}
/*
* Record the the fact that we have to scan this region of the
* string for IFS characters.
*/
STATIC void
recordregion(start, end, nulonly) {
register struct ifsregion *ifsp;
if (ifslastp == NULL) {
ifsp = &ifsfirst;
} else {
ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion));
ifslastp->next = ifsp;
}
ifslastp = ifsp;
ifslastp->next = NULL;
ifslastp->begoff = start;
ifslastp->endoff = end;
ifslastp->nulonly = nulonly;
}
/*
* Break the argument string into pieces based upon IFS and add the
* strings to the argument list. The regions of the string to be
* searched for IFS characters have been stored by recordregion.
*/
STATIC void
ifsbreakup(string, arglist)
char *string;
struct arglist *arglist;
{
struct ifsregion *ifsp;
struct strlist *sp;
char *start;
register char *p;
char *q;
char *ifs;
start = string;
if (ifslastp != NULL) {
ifsp = &ifsfirst;
do {
p = string + ifsp->begoff;
ifs = ifsp->nulonly? nullstr : ifsval();
while (p < string + ifsp->endoff) {
q = p;
if (*p == CTLESC)
p++;
if (strchr(ifs, *p++)) {
if (q > start || *ifs != ' ') {
*q = '\0';
sp = (struct strlist *)stalloc(sizeof *sp);
sp->text = start;
*arglist->lastp = sp;
arglist->lastp = &sp->next;
}
if (*ifs == ' ') {
for (;;) {
if (p >= string + ifsp->endoff)
break;
q = p;
if (*p == CTLESC)
p++;
if (strchr(ifs, *p++) == NULL) {
p = q;
break;
}
}
}
start = p;
}
}
} while ((ifsp = ifsp->next) != NULL);
if (*start || (*ifs != ' ' && start > string)) {
sp = (struct strlist *)stalloc(sizeof *sp);
sp->text = start;
*arglist->lastp = sp;
arglist->lastp = &sp->next;
}
} else {
sp = (struct strlist *)stalloc(sizeof *sp);
sp->text = start;
*arglist->lastp = sp;
arglist->lastp = &sp->next;
}
}
/*
* Expand shell metacharacters. At this point, the only control characters
* should be escapes. The results are stored in the list exparg.
*/
char *expdir;
STATIC void
expandmeta(str)
struct strlist *str;
{
char *p;
struct strlist **savelastp;
struct strlist *sp;
char c;
while (str) {
if (fflag)
goto nometa;
p = str->text;
#if UDIR
if (p[0] == '/' && p[1] == 'u' && p[2] == '/')
str->text = p = expudir(p);
#endif
for (;;) { /* fast check for meta chars */
if ((c = *p++) == '\0')
goto nometa;
if (c == '*' || c == '?' || c == '[' || c == '!')
break;
}
savelastp = exparg.lastp;
INTOFF;
if (expdir == NULL)
expdir = ckmalloc(1024); /* I hope this is big enough */
expmeta(expdir, str->text);
ckfree(expdir);
expdir = NULL;
INTON;
if (exparg.lastp == savelastp) {
if (! zflag) {
nometa:
*exparg.lastp = str;
rmescapes(str->text);
exparg.lastp = &str->next;
}
} else {
*exparg.lastp = NULL;
*savelastp = sp = expsort(*savelastp);
while (sp->next != NULL)
sp = sp->next;
exparg.lastp = &sp->next;
}
str = str->next;
}
}
#if UDIR
/*
* Expand /u/username into the home directory for the specified user.
* We could use the getpw stuff here, but then we would have to load
* in stdio and who knows what else.
*/
#define MAXLOGNAME 32
#define MAXPWLINE 128
char *pfgets();
STATIC char *
expudir(path)
char *path;
{
register char *p, *q, *r;
char name[MAXLOGNAME];
char line[MAXPWLINE];
int i;
r = path; /* result on failure */
p = r + 3; /* the 3 skips "/u/" */
q = name;
while (*p && *p != '/') {
if (q >= name + MAXLOGNAME - 1)
return r; /* fail, name too long */
*q++ = *p++;
}
*q = '\0';
setinputfile("/etc/passwd", 1);
q = line + strlen(name);
while (pfgets(line, MAXPWLINE) != NULL) {
if (line[0] == name[0] && prefix(name, line) && *q == ':') {
/* skip to start of home directory */
i = 4;
do {
while (*++q && *q != ':');
} while (--i > 0);
if (*q == '\0')
break; /* fail, corrupted /etc/passwd */
q++;
for (r = q ; *r && *r != '\n' && *r != ':' ; r++);
*r = '\0'; /* nul terminate home directory */
i = r - q; /* i = strlen(q) */
r = stalloc(i + strlen(p) + 1);
scopy(q, r);
scopy(p, r + i);
TRACE(("expudir converts %s to %s\n", path, r));
didudir = 1;
path = r; /* succeed */
break;
}
}
popfile();
return r;
}
#endif
/*
* Do metacharacter (i.e. *, ?, [...]) expansion.
*/
STATIC void
expmeta(enddir, name)
char *enddir;
char *name;
{
register char *p;
char *q;
char *start;
char *endname;
int metaflag;
struct stat statb;
DIR *dirp;
struct dirent *dp;
int atend;
int matchdot;
metaflag = 0;
start = name;
for (p = name ; ; p++) {
if (*p == '*' || *p == '?')
metaflag = 1;
else if (*p == '[') {
q = p + 1;
if (*q == '!')
q++;
for (;;) {
if (*q == CTLESC)
q++;
if (*q == '/' || *q == '\0')
break;
if (*++q == ']') {
metaflag = 1;
break;
}
}
} else if (*p == '!' && p[1] == '!' && (p == name || p[-1] == '/')) {
metaflag = 1;
} else if (*p == '\0')
break;
else if (*p == CTLESC)
p++;
if (*p == '/') {
if (metaflag)
break;
start = p + 1;
}
}
if (metaflag == 0) { /* we've reached the end of the file name */
if (enddir != expdir)
metaflag++;
for (p = name ; ; p++) {
if (*p == CTLESC)
p++;
*enddir++ = *p;
if (*p == '\0')
break;
}
if (metaflag == 0 || stat(expdir, &statb) >= 0)
addfname(expdir);
return;
}
endname = p;
if (start != name) {
p = name;
while (p < start) {
if (*p == CTLESC)
p++;
*enddir++ = *p++;
}
}
if (enddir == expdir) {
p = ".";
} else if (enddir == expdir + 1 && *expdir == '/') {
p = "/";
} else {
p = expdir;
enddir[-1] = '\0';
}
if ((dirp = opendir(p)) == NULL)
return;
if (enddir != expdir)
enddir[-1] = '/';
if (*endname == 0) {
atend = 1;
} else {
atend = 0;
*endname++ = '\0';
}
matchdot = 0;
if (start[0] == '.' || start[0] == CTLESC && start[1] == '.')
matchdot++;
while (! int_pending() && (dp = readdir(dirp)) != NULL) {
if (dp->d_name[0] == '.' && ! matchdot)
continue;
if (patmatch(start, dp->d_name)) {
if (atend) {
scopy(dp->d_name, enddir);
addfname(expdir);
} else {
char *q;
for (p = enddir, q = dp->d_name ; *p++ = *q++ ;);
p[-1] = '/';
expmeta(p, endname);
}
}
}
closedir(dirp);
if (! atend)
endname[-1] = '/';
}
/*
* Add a file name to the list.
*/
STATIC void
addfname(name)
char *name;
{
char *p;
struct strlist *sp;
p = stalloc(strlen(name) + 1);
scopy(name, p);
sp = (struct strlist *)stalloc(sizeof *sp);
sp->text = p;
*exparg.lastp = sp;
exparg.lastp = &sp->next;
}
/*
* Sort the results of file name expansion. It calculates the number of
* strings to sort and then calls msort (short for merge sort) to do the
* work.
*/
STATIC struct strlist *
expsort(str)
struct strlist *str;
{
int len;
struct strlist *sp;
len = 0;
for (sp = str ; sp ; sp = sp->next)
len++;
return msort(str, len);
}
STATIC struct strlist *
msort(list, len)
struct strlist *list;
{
struct strlist *p, *q;
struct strlist **lpp;
int half;
int n;
if (len <= 1)
return list;
half = len >> 1;
p = list;
for (n = half ; --n >= 0 ; ) {
q = p;
p = p->next;
}
q->next = NULL; /* terminate first half of list */
q = msort(list, half); /* sort first half of list */
p = msort(p, len - half); /* sort second half */
lpp = &list;
for (;;) {
if (strcmp(p->text, q->text) < 0) {
*lpp = p;
lpp = &p->next;
if ((p = *lpp) == NULL) {
*lpp = q;
break;
}
} else {
*lpp = q;
lpp = &q->next;
if ((q = *lpp) == NULL) {
*lpp = p;
break;
}
}
}
return list;
}
/*
* Returns true if the pattern matches the string.
*/
int
patmatch(pattern, string)
char *pattern;
char *string;
{
if (pattern[0] == '!' && pattern[1] == '!')
return 1 - pmatch(pattern + 2, string);
else
return pmatch(pattern, string);
}
STATIC int
pmatch(pattern, string)
char *pattern;
char *string;
{
register char *p, *q;
register char c;
p = pattern;
q = string;
for (;;) {
switch (c = *p++) {
case '\0':
goto breakloop;
case CTLESC:
if (*q++ != *p++)
return 0;
break;
case '?':
if (*q++ == '\0')
return 0;
break;
case '*':
c = *p;
if (c != CTLESC && c != '?' && c != '*' && c != '[') {
while (*q != c) {
if (*q == '\0')
return 0;
q++;
}
}
do {
if (pmatch(p, q))
return 1;
} while (*q++ != '\0');
return 0;
case '[': {
char *endp;
int invert, found;
char chr;
endp = p;
if (*endp == '!')
endp++;
for (;;) {
if (*endp == '\0')
goto dft; /* no matching ] */
if (*endp == CTLESC)
endp++;
if (*++endp == ']')
break;
}
invert = 0;
if (*p == '!') {
invert++;
p++;
}
found = 0;
chr = *q++;
c = *p++;
do {
if (c == CTLESC)
c = *p++;
if (*p == '-' && p[1] != ']') {
p++;
if (*p == CTLESC)
p++;
if (chr >= c && chr <= *p)
found = 1;
p++;
} else {
if (chr == c)
found = 1;
}
} while ((c = *p++) != ']');
if (found == invert)
return 0;
break;
}
dft: default:
if (*q++ != c)
return 0;
break;
}
}
breakloop:
if (*q != '\0')
return 0;
return 1;
}
/*
* Remove any CTLESC characters from a string.
*/
void
rmescapes(str)
char *str;
{
register char *p, *q;
p = str;
while (*p != CTLESC) {
if (*p++ == '\0')
return;
}
q = p;
while (*p) {
if (*p == CTLESC)
p++;
*q++ = *p++;
}
*q = '\0';
}
/*
* See if a pattern matches in a case statement.
*/
int
casematch(pattern, val)
union node *pattern;
char *val;
{
struct stackmark smark;
int result;
char *p;
setstackmark(&smark);
argbackq = pattern->narg.backquote;
STARTSTACKSTR(expdest);
ifslastp = NULL;
argstr(pattern->narg.text, 0);
STPUTC('\0', expdest);
p = grabstackstr(expdest);
result = patmatch(p, val);
popstackmark(&smark);
return result;
}
EOF
if test `wc -c < expand.c` -ne 22554
then echo 'expand.c is the wrong size'
fi
echo extracting init.h
cat > init.h <<\EOF
/*
* Copyright (C) 1989 by Kenneth Almquist. All rights reserved.
* This file is part of ash, which is distributed under the terms specified
* by the Ash General Public License. See the file named LICENSE.
*/
#ifdef __STDC__
void init(void);
void reset(void);
void initshellproc(void);
#else
void init();
void reset();
void initshellproc();
#endif
EOF
if test `wc -c < init.h` -ne 355
then echo 'init.h is the wrong size'
fi
echo extracting input.h
cat > input.h <<\EOF
/*
* Copyright (C) 1989 by Kenneth Almquist. All rights reserved.
* This file is part of ash, which is distributed under the terms specified
* by the Ash General Public License. See the file named LICENSE.
*/
/* PEOF (the end of file marker) is defined in syntax.h */
/*
* The input line number. Input.c just defines this variable, and saves
* and restores it when files are pushed and popped. The user of this
* package must set its value.
*/
extern int plinno;
extern int parsenleft; /* number of characters left in input buffer */
extern char *parsenextc; /* next character in input buffer */
#ifdef __STDC__
char *pfgets(char *, int);
int pgetc(void);
int preadbuffer(void);
void pungetc(void);
void ppushback(char *, int);
void setinputfile(char *, int);
void setinputfd(int, int);
void setinputstring(char *, int);
void popfile(void);
void popallfiles(void);
void closescript(void);
#else
char *pfgets();
int pgetc();
int preadbuffer();
void pungetc();
void ppushback();
void setinputfile();
void setinputfd();
void setinputstring();
void popfile();
void popallfiles();
void closescript();
#endif
#define pgetc_macro() (--parsenleft >= 0? *parsenextc++ : preadbuffer())
EOF
if test `wc -c < input.h` -ne 1194
then echo 'input.h is the wrong size'
fi
echo extracting input.c
cat > input.c <<\EOF
/*
* Copyright (C) 1989 by Kenneth Almquist. All rights reserved.
* This file is part of ash, which is distributed under the terms specified
* by the Ash General Public License. See the file named LICENSE.
*
* This file implements the input routines used by the parser.
*/
#include <stdio.h> /* defines BUFSIZ */
#include "shell.h"
#include "syntax.h"
#include "input.h"
#include "output.h"
#include "memalloc.h"
#include "error.h"
#include <fcntl.h>
#include "myerrno.h"
#define EOF_NLEFT -99 /* value of parsenleft when EOF pushed back */
/*
* The parsefile structure pointed to by the global variable parsefile
* contains information about the current file being read.
*/
MKINIT
struct parsefile {
int linno; /* current line */
int fd; /* file descriptor (or -1 if string) */
int nleft; /* number of chars left in buffer */
char *nextc; /* next char in buffer */
struct parsefile *prev; /* preceding file on stack */
char *buf; /* input buffer */
};
int plinno = 1; /* input line number */
MKINIT int parsenleft; /* copy of parsefile->nleft */
char *parsenextc; /* copy of parsefile->nextc */
MKINIT struct parsefile basepf; /* top level input file */
char basebuf[BUFSIZ]; /* buffer for top level input file */
struct parsefile *parsefile = &basepf; /* current input file */
char *pushedstring; /* copy of parsenextc when text pushed back */
int pushednleft; /* copy of parsenleft when text pushed back */
#ifdef __STDC__
STATIC void pushfile(void);
#else
STATIC void pushfile();
#endif
#ifdef mkinit
INCLUDE "input.h"
INCLUDE "error.h"
INIT {
extern char basebuf[];
basepf.nextc = basepf.buf = basebuf;
}
RESET {
if (exception != EXSHELLPROC)
parsenleft = 0; /* clear input buffer */
popallfiles();
}
SHELLPROC {
popallfiles();
}
#endif
/*
* Read a line from the script.
*/
char *
pfgets(line, len)
char *line;
{
register char *p = line;
int nleft = len;
int c;
while (--nleft > 0) {
c = pgetc_macro();
if (c == PEOF) {
if (p == line)
return NULL;
break;
}
*p++ = c;
if (c == '\n')
break;
}
*p = '\0';
return line;
}
/*
* Read a character from the script, returning PEOF on end of file.
* Nul characters in the input are silently discarded.
*/
int
pgetc() {
return pgetc_macro();
}
/*
* Refill the input buffer and return the next input character:
*
* 1) If a string was pushed back on the input, switch back to the regular
* buffer.
* 2) If an EOF was pushed back (parsenleft == EOF_NLEFT) or we are reading
* from a string so we can't refill the buffer, return EOF.
* 3) Call read to read in the characters.
* 4) Delete all nul characters from the buffer.
*/
int
preadbuffer() {
register char *p, *q;
register int i;
if (pushedstring) {
parsenextc = pushedstring;
pushedstring = NULL;
parsenleft = pushednleft;
if (--parsenleft >= 0)
return *parsenextc++;
}
if (parsenleft == EOF_NLEFT || parsefile->buf == NULL)
return PEOF;
flushout(&output);
flushout(&errout);
retry:
p = parsenextc = parsefile->buf;
i = read(parsefile->fd, p, BUFSIZ);
if (i <= 0) {
if (i < 0) {
if (errno == EINTR)
goto retry;
#ifdef BSD
if (parsefile->fd == 0 && errno == EWOULDBLOCK) {
int flags = fcntl(0, F_GETFL, 0);
if (flags >= 0 && flags & FNDELAY) {
flags &=~ FNDELAY;
if (fcntl(0, F_SETFL, flags) >= 0) {
out2str("ash: turning off NDELAY mode\n");
goto retry;
}
}
}
#endif
}
#ifdef SYSV
if (i == 0 && parsefile->fd == 0) {
int flags = fcntl(0, F_GETFL, 0);
if (flags >= 0 && flags & O_NDELAY) {
flags &=~ O_NDELAY;
if (fcntl(0, F_SETFL, flags) >= 0) {
out2str("ash: turning off NDELAY mode\n");
goto retry;
}
}
}
#endif
parsenleft = EOF_NLEFT;
return PEOF;
}
parsenleft = i - 1;
/* delete nul characters */
for (;;) {
if (*p++ == '\0')
break;
if (--i <= 0)
return *parsenextc++; /* no nul characters */
}
q = p - 1;
while (--i > 0) {
if (*p != '\0')
*q++ = *p;
p++;
}
if (q == parsefile->buf)
goto retry; /* buffer contained nothing but nuls */
parsenleft = q - parsefile->buf - 1;
return *parsenextc++;
}
/*
* Undo the last call to pgetc. Only one character may be pushed back.
* PEOF may be pushed back.
*/
void
pungetc() {
parsenleft++;
parsenextc--;
}
/*
* Push a string back onto the input. This code doesn't work if the user
* tries to push back more than one string at once.
*/
void
ppushback(string, length)
char *string;
{
pushedstring = parsenextc;
pushednleft = parsenleft;
parsenextc = string;
parsenleft = length;
}
/*
* Set the input to take input from a file. If push is set, push the
* old input onto the stack first.
*/
void
setinputfile(fname, push)
char *fname;
{
int fd;
int fd2;
INTOFF;
if ((fd = open(fname, O_RDONLY)) < 0)
error("Can't open %s", fname);
if (fd < 10) {
fd2 = copyfd(fd, 10);
close(fd);
if (fd2 < 0)
error("Out of file descriptors");
fd = fd2;
}
setinputfd(fd, push);
INTON;
}
/*
* Like setinputfile, but takes an open file descriptor. Call this with
* interrupts off.
*/
void
setinputfd(fd, push) {
if (push) {
pushfile();
parsefile->buf = ckmalloc(BUFSIZ);
}
if (parsefile->fd > 0)
close(parsefile->fd);
parsefile->fd = fd;
if (parsefile->buf == NULL)
parsefile->buf = ckmalloc(BUFSIZ);
parsenleft = 0;
plinno = 1;
}
/*
* Like setinputfile, but takes input from a string.
*/
void
setinputstring(string, push)
char *string;
{
INTOFF;
if (push)
pushfile();
parsenextc = string;
parsenleft = strlen(string);
parsefile->buf = NULL;
plinno = 1;
INTON;
}
/*
* To handle the "." command, a stack of input files is used. Pushfile
* adds a new entry to the stack and popfile restores the previous level.
*/
STATIC void
pushfile() {
struct parsefile *pf;
parsefile->nleft = parsenleft;
parsefile->nextc = parsenextc;
parsefile->linno = plinno;
pf = (struct parsefile *)ckmalloc(sizeof (struct parsefile));
pf->prev = parsefile;
pf->fd = -1;
parsefile = pf;
}
void
popfile() {
struct parsefile *pf = parsefile;
INTOFF;
if (pf->fd >= 0)
close(pf->fd);
if (pf->buf)
ckfree(pf->buf);
parsefile = pf->prev;
ckfree(pf);
parsenleft = parsefile->nleft;
parsenextc = parsefile->nextc;
plinno = parsefile->linno;
INTON;
}
/*
* Return to top level.
*/
void
popallfiles() {
while (parsefile != &basepf)
popfile();
}
/*
* Close the file(s) that the shell is reading commands from. Called
* after a fork is done.
*/
void
closescript() {
popallfiles();
if (parsefile->fd > 0) {
close(parsefile->fd);
parsefile->fd = 0;
}
}
EOF
if test `wc -c < input.c` -ne 7288
then echo 'input.c is the wrong size'
fi
echo Archive 3 unpacked
exit
--
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