minix/commands/sh/sh1.c
2005-04-21 14:53:53 +00:00

952 lines
14 KiB
C
Executable file

#define Extern extern
#include <sys/types.h>
#include <signal.h>
#include <errno.h>
#include <setjmp.h>
#include "sh.h"
/* -------- sh.c -------- */
/*
* shell
*/
/* #include "sh.h" */
int intr;
int inparse;
char flags['z'-'a'+1];
char *flag = flags-'a';
char *elinep = line+sizeof(line)-5;
char *null = "";
int heedint =1;
struct env e ={line, iostack, iostack-1,
(xint *)NULL, FDBASE, (struct env *)NULL};
extern char **environ; /* environment pointer */
/*
* default shell, search rules
*/
char shellname[] = "/bin/sh";
char search[] = ":/bin:/usr/bin";
_PROTOTYPE(void (*qflag), (int)) = SIG_IGN;
_PROTOTYPE(int main, (int argc, char **argv ));
_PROTOTYPE(int newfile, (char *s ));
_PROTOTYPE(static char *findeq, (char *cp ));
_PROTOTYPE(static char *cclass, (char *p, int sub ));
_PROTOTYPE(void initarea, (void));
int main(argc, argv)
int argc;
register char **argv;
{
register int f;
register char *s;
int cflag;
char *name, **ap;
int (*iof)();
initarea();
if ((ap = environ) != NULL) {
while (*ap)
assign(*ap++, !COPYV);
for (ap = environ; *ap;)
export(lookup(*ap++));
}
closeall();
areanum = 1;
shell = lookup("SHELL");
if (shell->value == null)
setval(shell, shellname);
export(shell);
homedir = lookup("HOME");
if (homedir->value == null)
setval(homedir, "/");
export(homedir);
setval(lookup("$"), itoa(getpid(), 5));
path = lookup("PATH");
if (path->value == null)
setval(path, search);
export(path);
ifs = lookup("IFS");
if (ifs->value == null)
setval(ifs, " \t\n");
prompt = lookup("PS1");
if (prompt->value == null)
#ifndef UNIXSHELL
setval(prompt, "$ ");
#else
setval(prompt, "% ");
#endif
if (geteuid() == 0) {
setval(prompt, "# ");
prompt->status &= ~EXPORT;
}
cprompt = lookup("PS2");
if (cprompt->value == null)
setval(cprompt, "> ");
iof = filechar;
cflag = 0;
name = *argv++;
if (--argc >= 1) {
if(argv[0][0] == '-' && argv[0][1] != '\0') {
for (s = argv[0]+1; *s; s++)
switch (*s) {
case 'c':
prompt->status &= ~EXPORT;
cprompt->status &= ~EXPORT;
setval(prompt, "");
setval(cprompt, "");
cflag = 1;
if (--argc > 0)
PUSHIO(aword, *++argv, iof = nlchar);
break;
case 'q':
qflag = SIG_DFL;
break;
case 's':
/* standard input */
break;
case 't':
prompt->status &= ~EXPORT;
setval(prompt, "");
iof = linechar;
break;
case 'i':
talking++;
default:
if (*s>='a' && *s<='z')
flag[*s]++;
}
} else {
argv--;
argc++;
}
if (iof == filechar && --argc > 0) {
setval(prompt, "");
setval(cprompt, "");
prompt->status &= ~EXPORT;
cprompt->status &= ~EXPORT;
if (newfile(name = *++argv))
exit(1);
}
}
setdash();
if (e.iop < iostack) {
PUSHIO(afile, 0, iof);
if (isatty(0) && isatty(1) && !cflag)
talking++;
}
signal(SIGQUIT, qflag);
if (name && name[0] == '-') {
talking++;
if ((f = open(".profile", 0)) >= 0)
next(remap(f));
if ((f = open("/etc/profile", 0)) >= 0)
next(remap(f));
}
if (talking)
signal(SIGTERM, sig);
if (signal(SIGINT, SIG_IGN) != SIG_IGN)
signal(SIGINT, onintr);
dolv = argv;
dolc = argc;
dolv[0] = name;
if (dolc > 1)
for (ap = ++argv; --argc > 0;)
if (assign(*ap = *argv++, !COPYV))
dolc--; /* keyword */
else
ap++;
setval(lookup("#"), putn((--dolc < 0) ? (dolc = 0) : dolc));
for (;;) {
if (talking && e.iop <= iostack)
prs(prompt->value);
onecommand();
}
}
void
setdash()
{
register char *cp, c;
char m['z'-'a'+1];
cp = m;
for (c='a'; c<='z'; c++)
if (flag[c])
*cp++ = c;
*cp = 0;
setval(lookup("-"), m);
}
int
newfile(s)
register char *s;
{
register f;
if (strcmp(s, "-") != 0) {
f = open(s, 0);
if (f < 0) {
prs(s);
err(": cannot open");
return(1);
}
} else
f = 0;
next(remap(f));
return(0);
}
void
onecommand()
{
register i;
jmp_buf m1;
while (e.oenv)
quitenv();
areanum = 1;
freehere(areanum);
freearea(areanum);
garbage();
wdlist = 0;
iolist = 0;
e.errpt = 0;
e.linep = line;
yynerrs = 0;
multiline = 0;
inparse = 1;
intr = 0;
execflg = 0;
setjmp(failpt = m1); /* Bruce Evans' fix */
if (setjmp(failpt = m1) || yyparse() || intr) {
while (e.oenv)
quitenv();
scraphere();
if (!talking && intr)
leave();
inparse = 0;
intr = 0;
return;
}
inparse = 0;
brklist = 0;
intr = 0;
execflg = 0;
if (!flag['n'])
execute(outtree, NOPIPE, NOPIPE, 0);
if (!talking && intr) {
execflg = 0;
leave();
}
if ((i = trapset) != 0) {
trapset = 0;
runtrap(i);
}
}
void
fail()
{
longjmp(failpt, 1);
/* NOTREACHED */
}
void
leave()
{
if (execflg)
fail();
scraphere();
freehere(1);
runtrap(0);
exit(exstat);
/* NOTREACHED */
}
void
warn(s)
register char *s;
{
if(*s) {
prs(s);
exstat = -1;
}
prs("\n");
if (flag['e'])
leave();
}
void
err(s)
char *s;
{
warn(s);
if (flag['n'])
return;
if (!talking)
leave();
if (e.errpt)
longjmp(e.errpt, 1);
closeall();
e.iop = e.iobase = iostack;
}
int
newenv(f)
int f;
{
register struct env *ep;
if (f) {
quitenv();
return(1);
}
ep = (struct env *) space(sizeof(*ep));
if (ep == NULL) {
while (e.oenv)
quitenv();
fail();
}
*ep = e;
e.oenv = ep;
e.errpt = errpt;
return(0);
}
void
quitenv()
{
register struct env *ep;
register fd;
if ((ep = e.oenv) != NULL) {
fd = e.iofd;
e = *ep;
/* should close `'d files */
DELETE(ep);
while (--fd >= e.iofd)
close(fd);
}
}
/*
* Is any character from s1 in s2?
*/
int
anys(s1, s2)
register char *s1, *s2;
{
while (*s1)
if (any(*s1++, s2))
return(1);
return(0);
}
/*
* Is character c in s?
*/
int
any(c, s)
register int c;
register char *s;
{
while (*s)
if (*s++ == c)
return(1);
return(0);
}
char *
putn(n)
register int n;
{
return(itoa(n, -1));
}
char *
itoa(u, n)
register unsigned u;
int n;
{
register char *cp;
static char s[20];
int m;
m = 0;
if (n < 0 && (int) u < 0) {
m++;
u = -u;
}
cp = s+sizeof(s);
*--cp = 0;
do {
*--cp = u%10 + '0';
u /= 10;
} while (--n > 0 || u);
if (m)
*--cp = '-';
return(cp);
}
void
next(f)
int f;
{
PUSHIO(afile, f, filechar);
}
void
onintr(s)
int s; /* ANSI C requires a parameter */
{
signal(SIGINT, onintr);
intr = 1;
if (talking) {
if (inparse) {
prs("\n");
fail();
}
}
else if (heedint) {
execflg = 0;
leave();
}
}
int
letter(c)
register c;
{
return((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || c == '_');
}
int
digit(c)
register c;
{
return(c >= '0' && c <= '9');
}
int
letnum(c)
register c;
{
return(letter(c) || digit(c));
}
char *
space(n)
int n;
{
register char *cp;
if ((cp = getcell(n)) == 0)
err("out of string space");
return(cp);
}
char *
strsave(s, a)
register char *s;
int a;
{
register char *cp, *xp;
if ((cp = space(strlen(s)+1)) != NULL) {
setarea((char *)cp, a);
for (xp = cp; (*xp++ = *s++) != '\0';)
;
return(cp);
}
return("");
}
void
xfree(s)
register char *s;
{
DELETE(s);
}
/*
* trap handling
*/
void
sig(i)
register int i;
{
trapset = i;
signal(i, sig);
}
void runtrap(i)
int i;
{
char *trapstr;
if ((trapstr = trap[i]) == NULL)
return;
if (i == 0)
trap[i] = 0;
RUN(aword, trapstr, nlchar);
}
/* -------- var.c -------- */
/* #include "sh.h" */
/*
* Find the given name in the dictionary
* and return its value. If the name was
* not previously there, enter it now and
* return a null value.
*/
struct var *
lookup(n)
register char *n;
{
register struct var *vp;
register char *cp;
register int c;
static struct var dummy;
if (digit(*n)) {
dummy.name = n;
for (c = 0; digit(*n) && c < 1000; n++)
c = c*10 + *n-'0';
dummy.status = RONLY;
dummy.value = c <= dolc? dolv[c]: null;
return(&dummy);
}
for (vp = vlist; vp; vp = vp->next)
if (eqname(vp->name, n))
return(vp);
cp = findeq(n);
vp = (struct var *)space(sizeof(*vp));
if (vp == 0 || (vp->name = space((int)(cp-n)+2)) == 0) {
dummy.name = dummy.value = "";
return(&dummy);
}
for (cp = vp->name; (*cp = *n++) && *cp != '='; cp++)
;
if (*cp == 0)
*cp = '=';
*++cp = 0;
setarea((char *)vp, 0);
setarea((char *)vp->name, 0);
vp->value = null;
vp->next = vlist;
vp->status = GETCELL;
vlist = vp;
return(vp);
}
/*
* give variable at `vp' the value `val'.
*/
void
setval(vp, val)
struct var *vp;
char *val;
{
nameval(vp, val, (char *)NULL);
}
/*
* if name is not NULL, it must be
* a prefix of the space `val',
* and end with `='.
* this is all so that exporting
* values is reasonably painless.
*/
void
nameval(vp, val, name)
register struct var *vp;
char *val, *name;
{
register char *cp, *xp;
char *nv;
int fl;
if (vp->status & RONLY) {
for (xp = vp->name; *xp && *xp != '=';)
putc(*xp++);
err(" is read-only");
return;
}
fl = 0;
if (name == NULL) {
xp = space(strlen(vp->name)+strlen(val)+2);
if (xp == 0)
return;
/* make string: name=value */
setarea((char *)xp, 0);
name = xp;
for (cp = vp->name; (*xp = *cp++) && *xp!='='; xp++)
;
if (*xp++ == 0)
xp[-1] = '=';
nv = xp;
for (cp = val; (*xp++ = *cp++) != '\0';)
;
val = nv;
fl = GETCELL;
}
if (vp->status & GETCELL)
xfree(vp->name); /* form new string `name=value' */
vp->name = name;
vp->value = val;
vp->status |= fl;
}
void
export(vp)
struct var *vp;
{
vp->status |= EXPORT;
}
void
ronly(vp)
struct var *vp;
{
if (letter(vp->name[0])) /* not an internal symbol ($# etc) */
vp->status |= RONLY;
}
int
isassign(s)
register char *s;
{
if (!letter((int)*s))
return(0);
for (; *s != '='; s++)
if (*s == 0 || !letnum(*s))
return(0);
return(1);
}
int
assign(s, cf)
register char *s;
int cf;
{
register char *cp;
struct var *vp;
if (!letter(*s))
return(0);
for (cp = s; *cp != '='; cp++)
if (*cp == 0 || !letnum(*cp))
return(0);
vp = lookup(s);
nameval(vp, ++cp, cf == COPYV? (char *)NULL: s);
if (cf != COPYV)
vp->status &= ~GETCELL;
return(1);
}
int
checkname(cp)
register char *cp;
{
if (!letter(*cp++))
return(0);
while (*cp)
if (!letnum(*cp++))
return(0);
return(1);
}
void
putvlist(f, out)
register int f, out;
{
register struct var *vp;
for (vp = vlist; vp; vp = vp->next)
if (vp->status & f && letter(*vp->name)) {
if (vp->status & EXPORT)
write(out, "export ", 7);
if (vp->status & RONLY)
write(out, "readonly ", 9);
write(out, vp->name, (int)(findeq(vp->name) - vp->name));
write(out, "\n", 1);
}
}
int
eqname(n1, n2)
register char *n1, *n2;
{
for (; *n1 != '=' && *n1 != 0; n1++)
if (*n2++ != *n1)
return(0);
return(*n2 == 0 || *n2 == '=');
}
static char *
findeq(cp)
register char *cp;
{
while (*cp != '\0' && *cp != '=')
cp++;
return(cp);
}
/* -------- gmatch.c -------- */
/*
* int gmatch(string, pattern)
* char *string, *pattern;
*
* Match a pattern as in sh(1).
*/
#define CMASK 0377
#define QUOTE 0200
#define QMASK (CMASK&~QUOTE)
#define NOT '!' /* might use ^ */
int
gmatch(s, p)
register char *s, *p;
{
register int sc, pc;
if (s == NULL || p == NULL)
return(0);
while ((pc = *p++ & CMASK) != '\0') {
sc = *s++ & QMASK;
switch (pc) {
case '[':
if ((p = cclass(p, sc)) == NULL)
return(0);
break;
case '?':
if (sc == 0)
return(0);
break;
case '*':
s--;
do {
if (*p == '\0' || gmatch(s, p))
return(1);
} while (*s++ != '\0');
return(0);
default:
if (sc != (pc&~QUOTE))
return(0);
}
}
return(*s == 0);
}
static char *
cclass(p, sub)
register char *p;
register int sub;
{
register int c, d, not, found;
if ((not = *p == NOT) != 0)
p++;
found = not;
do {
if (*p == '\0')
return((char *)NULL);
c = *p & CMASK;
if (p[1] == '-' && p[2] != ']') {
d = p[2] & CMASK;
p++;
} else
d = c;
if (c == sub || (c <= sub && sub <= d))
found = !not;
} while (*++p != ']');
return(found? p+1: (char *)NULL);
}
/* -------- area.c -------- */
#define REGSIZE sizeof(struct region)
#define GROWBY 256
#undef SHRINKBY 64
#define FREE 32767
#define BUSY 0
#define ALIGN (sizeof(int)-1)
/* #include "area.h" */
struct region {
struct region *next;
int area;
};
/*
* All memory between (char *)areabot and (char *)(areatop+1) is
* exclusively administered by the area management routines.
* It is assumed that sbrk() and brk() manipulate the high end.
*/
static struct region *areabot; /* bottom of area */
static struct region *areatop; /* top of area */
static struct region *areanxt; /* starting point of scan */
void
initarea()
{
while ((int)sbrk(0) & ALIGN)
sbrk(1);
areabot = (struct region *)sbrk(REGSIZE);
areabot->next = areabot;
areabot->area = BUSY;
areatop = areabot;
areanxt = areabot;
}
char *
getcell(nbytes)
unsigned nbytes;
{
register int nregio;
register struct region *p, *q;
register i;
if (nbytes == 0)
abort(); /* silly and defeats the algorithm */
/*
* round upwards and add administration area
*/
nregio = (nbytes+(REGSIZE-1))/REGSIZE + 1;
for (p = areanxt;;) {
if (p->area > areanum) {
/*
* merge free cells
*/
while ((q = p->next)->area > areanum && q != areanxt)
p->next = q->next;
/*
* exit loop if cell big enough
*/
if (q >= p + nregio)
goto found;
}
p = p->next;
if (p == areanxt)
break;
}
i = nregio >= GROWBY ? nregio : GROWBY;
p = (struct region *)sbrk(i * REGSIZE);
if (p == (struct region *)-1)
return((char *)NULL);
p--;
if (p != areatop)
abort(); /* allocated areas are contiguous */
q = p + i;
p->next = q;
p->area = FREE;
q->next = areabot;
q->area = BUSY;
areatop = q;
found:
/*
* we found a FREE area big enough, pointed to by 'p', and up to 'q'
*/
areanxt = p + nregio;
if (areanxt < q) {
/*
* split into requested area and rest
*/
if (areanxt+1 > q)
abort(); /* insufficient space left for admin */
areanxt->next = q;
areanxt->area = FREE;
p->next = areanxt;
}
p->area = areanum;
return((char *)(p+1));
}
void
freecell(cp)
char *cp;
{
register struct region *p;
if ((p = (struct region *)cp) != NULL) {
p--;
if (p < areanxt)
areanxt = p;
p->area = FREE;
}
}
void
freearea(a)
register int a;
{
register struct region *p, *top;
top = areatop;
for (p = areabot; p != top; p = p->next)
if (p->area >= a)
p->area = FREE;
}
void
setarea(cp,a)
char *cp;
int a;
{
register struct region *p;
if ((p = (struct region *)cp) != NULL)
(p-1)->area = a;
}
int
getarea(cp)
char *cp;
{
return ((struct region*)cp-1)->area;
}
void
garbage()
{
register struct region *p, *q, *top;
top = areatop;
for (p = areabot; p != top; p = p->next) {
if (p->area > areanum) {
while ((q = p->next)->area > areanum)
p->next = q->next;
areanxt = p;
}
}
#ifdef SHRINKBY
if (areatop >= q + SHRINKBY && q->area > areanum) {
brk((char *)(q+1));
q->next = areabot;
q->area = BUSY;
areatop = q;
}
#endif
}