ref: 5c1feb0ef0b795e5de71e956f9ccddcd5c4b7f21
dir: /sys/src/cmd/rc/exec.c/
#include "rc.h"
#include "getflags.h"
#include "exec.h"
#include "io.h"
#include "fns.h"
/*
* Start executing the given code at the given pc with the given redirection
*/
char *argv0="rc";
void
start(code *c, int pc, var *local)
{
struct thread *p = new(struct thread);
p->code = codecopy(c);
p->pc = pc;
p->argv = 0;
p->redir = p->startredir = runq?runq->redir:0;
p->local = local;
p->cmdfile = 0;
p->cmdfd = 0;
p->eof = 0;
p->iflag = 0;
p->lineno = 1;
p->ret = runq;
runq = p;
}
word*
Newword(char *wd, word *next)
{
word *p = new(word);
p->word = wd;
p->next = next;
p->glob = 0;
return p;
}
word*
Pushword(char *wd)
{
word *w;
if(runq->argv==0)
panic("pushword but no argv!", 0);
w = Newword(wd, runq->argv->words);
runq->argv->words = w;
return w;
}
word*
newword(char *wd, word *next)
{
return Newword(estrdup(wd), next);
}
word*
pushword(char *wd)
{
return Pushword(estrdup(wd));
}
void
popword(void)
{
word *p;
if(runq->argv==0)
panic("popword but no argv!", 0);
p = runq->argv->words;
if(p==0)
panic("popword but no word!", 0);
runq->argv->words = p->next;
free(p->word);
free(p);
}
void
freelist(word *w)
{
word *nw;
while(w){
nw = w->next;
free(w->word);
free(w);
w = nw;
}
}
void
pushlist(void)
{
list *p = new(list);
p->next = runq->argv;
p->words = 0;
runq->argv = p;
}
void
poplist(void)
{
list *p = runq->argv;
if(p==0)
panic("poplist but no argv", 0);
freelist(p->words);
runq->argv = p->next;
free(p);
}
int
count(word *w)
{
int n;
for(n = 0;w;n++) w = w->next;
return n;
}
void
pushredir(int type, int from, int to)
{
redir * rp = new(redir);
rp->type = type;
rp->from = from;
rp->to = to;
rp->next = runq->redir;
runq->redir = rp;
}
var*
newvar(char *name, var *next)
{
var *v = new(var);
v->name = estrdup(name);
v->val = 0;
v->fn = 0;
v->changed = 0;
v->fnchanged = 0;
v->next = next;
return v;
}
/*
* get command line flags, initialize keywords & traps.
* get values from environment.
* set $pid, $cflag, $*
* fabricate bootstrap code and start it (*=(argv);. /usr/lib/rcmain $*)
* start interpreting code
*/
void
main(int argc, char *argv[])
{
code bootstrap[17];
char num[12], *rcmain;
int i;
argc = getflags(argc, argv, "SsrdiIlxepvVc:1m:1[command]", 1);
if(argc==-1)
usage("[file [arg ...]]");
if(argv[0][0]=='-')
flag['l'] = flagset;
if(flag['I'])
flag['i'] = 0;
else if(flag['i']==0 && argc==1 && Isatty(0)) flag['i'] = flagset;
rcmain = flag['m']?flag['m'][0]:Rcmain;
err = openfd(2);
kinit();
Trapinit();
Vinit();
inttoascii(num, mypid = getpid());
setvar("pid", newword(num, (word *)0));
setvar("cflag", flag['c']?newword(flag['c'][0], (word *)0)
:(word *)0);
setvar("rcname", newword(argv[0], (word *)0));
i = 0;
bootstrap[i++].i = 1;
bootstrap[i++].f = Xmark;
bootstrap[i++].f = Xword;
bootstrap[i++].s="*";
bootstrap[i++].f = Xassign;
bootstrap[i++].f = Xmark;
bootstrap[i++].f = Xmark;
bootstrap[i++].f = Xword;
bootstrap[i++].s="*";
bootstrap[i++].f = Xdol;
bootstrap[i++].f = Xword;
bootstrap[i++].s = rcmain;
bootstrap[i++].f = Xword;
bootstrap[i++].s=".";
bootstrap[i++].f = Xsimple;
bootstrap[i++].f = Xexit;
bootstrap[i].i = 0;
start(bootstrap, 1, (var *)0);
/* prime bootstrap argv */
pushlist();
argv0 = estrdup(argv[0]);
for(i = argc-1;i!=0;--i) pushword(argv[i]);
for(;;){
if(flag['r'])
pfnc(err, runq);
runq->pc++;
(*runq->code[runq->pc-1].f)();
if(ntrap)
dotrap();
}
}
/*
* Opcode routines
* Arguments on stack (...)
* Arguments in line [...]
* Code in line with jump around {...}
*
* Xappend(file)[fd] open file to append
* Xassign(name, val) assign val to name
* Xasync{... Xexit} make thread for {}, no wait
* Xbackq(split){... Xreturn} make thread for {}, push stdout
* Xbang complement condition
* Xcase(pat, value){...} exec code on match, leave (value) on
* stack
* Xclose[i] close file descriptor
* Xconc(left, right) concatenate, push results
* Xcount(name) push var count
* Xdelfn(name) delete function definition
* Xdeltraps(names) delete named traps
* Xdol(name) get variable value
* Xqdol(name) concatenate variable components
* Xdup[i j] dup file descriptor
* Xexit rc exits with status
* Xfalse{...} execute {} if false
* Xfn(name){... Xreturn} define function
* Xfor(var, list){... Xreturn} for loop
* Xglobs[string globsize] push globbing string
* Xjump[addr] goto
* Xlocal(name, val) create local variable, assign value
* Xmark mark stack
* Xmatch(pat, str) match pattern, set status
* Xpipe[i j]{... Xreturn}{... Xreturn} construct a pipe between 2 new threads,
* wait for both
* Xpipefd[type]{... Xreturn} connect {} to pipe (input or output,
* depending on type), push /dev/fd/??
* Xpopm(value) pop value from stack
* Xrdwr(file)[fd] open file for reading and writing
* Xread(file)[fd] open file to read
* Xsettraps(names){... Xreturn} define trap functions
* Xshowtraps print trap list
* Xsimple(args) run command and wait
* Xreturn kill thread
* Xsubshell{... Xexit} execute {} in a subshell and wait
* Xtrue{...} execute {} if true
* Xunlocal delete local variable
* Xword[string] push string
* Xwrite(file)[fd] open file to write
*/
void
Xappend(void)
{
char *file;
int f;
switch(count(runq->argv->words)){
default:
Xerror1(">> requires singleton");
return;
case 0:
Xerror1(">> requires file");
return;
case 1:
break;
}
file = runq->argv->words->word;
if((f = open(file, 1))<0 && (f = Creat(file))<0){
pfmt(err, "%s: ", file);
Xerror("can't open");
return;
}
Seek(f, 0L, 2);
pushredir(ROPEN, f, runq->code[runq->pc].i);
runq->pc++;
poplist();
}
void
Xsettrue(void)
{
setstatus("");
}
void
Xbang(void)
{
setstatus(truestatus()?"false":"");
}
void
Xclose(void)
{
pushredir(RCLOSE, runq->code[runq->pc].i, 0);
runq->pc++;
}
void
Xdup(void)
{
pushredir(RDUP, runq->code[runq->pc].i, runq->code[runq->pc+1].i);
runq->pc+=2;
}
void
Xeflag(void)
{
if(eflagok && !truestatus()) Xexit();
}
void
Xexit(void)
{
struct var *trapreq;
struct word *starval;
static int beenhere = 0;
if(getpid()==mypid && !beenhere){
trapreq = vlook("sigexit");
if(trapreq->fn){
beenhere = 1;
--runq->pc;
starval = vlook("*")->val;
start(trapreq->fn, trapreq->pc, (struct var *)0);
runq->local = newvar("*", runq->local);
runq->local->val = copywords(starval, (struct word *)0);
runq->local->changed = 1;
runq->redir = runq->startredir = 0;
return;
}
}
Exit(getstatus());
}
void
Xfalse(void)
{
if(truestatus()) runq->pc = runq->code[runq->pc].i;
else runq->pc++;
}
int ifnot; /* dynamic if not flag */
void
Xifnot(void)
{
if(ifnot)
runq->pc++;
else
runq->pc = runq->code[runq->pc].i;
}
void
Xjump(void)
{
runq->pc = runq->code[runq->pc].i;
}
void
Xmark(void)
{
pushlist();
}
void
Xpopm(void)
{
poplist();
}
void
Xread(void)
{
char *file;
int f;
switch(count(runq->argv->words)){
default:
Xerror1("< requires singleton\n");
return;
case 0:
Xerror1("< requires file\n");
return;
case 1:
break;
}
file = runq->argv->words->word;
if((f = open(file, 0))<0){
pfmt(err, "%s: ", file);
Xerror("can't open");
return;
}
pushredir(ROPEN, f, runq->code[runq->pc].i);
runq->pc++;
poplist();
}
void
Xrdwr(void)
{
char *file;
int f;
switch(count(runq->argv->words)){
default:
Xerror1("<> requires singleton\n");
return;
case 0:
Xerror1("<> requires file\n");
return;
case 1:
break;
}
file = runq->argv->words->word;
if((f = open(file, ORDWR))<0){
pfmt(err, "%s: ", file);
Xerror("can't open");
return;
}
pushredir(ROPEN, f, runq->code[runq->pc].i);
runq->pc++;
poplist();
}
void
turfredir(void)
{
while(runq->redir!=runq->startredir)
Xpopredir();
}
void
Xpopredir(void)
{
struct redir *rp = runq->redir;
if(rp==0)
panic("turfredir null!", 0);
runq->redir = rp->next;
if(rp->type==ROPEN)
close(rp->from);
free(rp);
}
void
Xreturn(void)
{
struct thread *p = runq;
turfredir();
while(p->argv) poplist();
codefree(p->code);
runq = p->ret;
free(p);
if(runq==0)
Exit(getstatus());
}
void
Xtrue(void)
{
if(truestatus()) runq->pc++;
else runq->pc = runq->code[runq->pc].i;
}
void
Xif(void)
{
ifnot = 1;
if(truestatus()) runq->pc++;
else runq->pc = runq->code[runq->pc].i;
}
void
Xwastrue(void)
{
ifnot = 0;
}
void
Xword(void)
{
pushword(runq->code[runq->pc++].s);
}
void
Xglobs(void)
{
word *w = pushword(runq->code[runq->pc++].s);
w->glob = runq->code[runq->pc++].i;
}
void
Xwrite(void)
{
char *file;
int f;
switch(count(runq->argv->words)){
default:
Xerror1("> requires singleton\n");
return;
case 0:
Xerror1("> requires file\n");
return;
case 1:
break;
}
file = runq->argv->words->word;
if((f = Creat(file))<0){
pfmt(err, "%s: ", file);
Xerror("can't open");
return;
}
pushredir(ROPEN, f, runq->code[runq->pc].i);
runq->pc++;
poplist();
}
char*
list2str(word *words)
{
char *value, *s, *t;
int len = 0;
word *ap;
for(ap = words;ap;ap = ap->next)
len+=1+strlen(ap->word);
value = emalloc(len+1);
s = value;
for(ap = words;ap;ap = ap->next){
for(t = ap->word;*t;) *s++=*t++;
*s++=' ';
}
if(s==value)
*s='\0';
else s[-1]='\0';
return value;
}
void
Xmatch(void)
{
word *p;
char *subject;
subject = list2str(runq->argv->words);
setstatus("no match");
for(p = runq->argv->next->words;p;p = p->next)
if(match(subject, p->word, '\0')){
setstatus("");
break;
}
free(subject);
poplist();
poplist();
}
void
Xcase(void)
{
word *p;
char *s;
int ok = 0;
s = list2str(runq->argv->next->words);
for(p = runq->argv->words;p;p = p->next){
if(match(s, p->word, '\0')){
ok = 1;
break;
}
}
free(s);
if(ok)
runq->pc++;
else
runq->pc = runq->code[runq->pc].i;
poplist();
}
word*
conclist(word *lp, word *rp, word *tail)
{
word *v, *p, **end;
int ln, rn;
for(end = &v;;){
ln = strlen(lp->word), rn = strlen(rp->word);
p = Newword(emalloc(ln+rn+1), (word *)0);
memmove(p->word, lp->word, ln);
memmove(p->word+ln, rp->word, rn+1);
if(lp->glob || rp->glob)
p->glob = Globsize(p->word);
*end = p, end = &p->next;
if(lp->next == 0 && rp->next == 0)
break;
if(lp->next) lp = lp->next;
if(rp->next) rp = rp->next;
}
*end = tail;
return v;
}
void
Xconc(void)
{
word *lp = runq->argv->words;
word *rp = runq->argv->next->words;
word *vp = runq->argv->next->next->words;
int lc = count(lp), rc = count(rp);
if(lc!=0 || rc!=0){
if(lc==0 || rc==0){
Xerror1("null list in concatenation");
return;
}
if(lc!=1 && rc!=1 && lc!=rc){
Xerror1("mismatched list lengths in concatenation");
return;
}
vp = conclist(lp, rp, vp);
}
poplist();
poplist();
runq->argv->words = vp;
}
char*
Str(word *a)
{
char *s = a->word;
if(a->glob){
a->glob = 0;
deglob(s);
}
return s;
}
void
Xassign(void)
{
var *v;
if(count(runq->argv->words)!=1){
Xerror1("variable name not singleton!");
return;
}
v = vlook(Str(runq->argv->words));
poplist();
freewords(v->val);
v->val = globlist(runq->argv->words);
v->changed = 1;
runq->argv->words = 0;
poplist();
}
/*
* copy arglist a, adding the copy to the front of tail
*/
word*
copywords(word *a, word *tail)
{
word *v = 0, **end;
for(end=&v;a;a = a->next,end=&(*end)->next)
*end = newword(a->word, 0);
*end = tail;
return v;
}
void
Xdol(void)
{
word *a, *star;
char *s, *t;
int n;
if(count(runq->argv->words)!=1){
Xerror1("variable name not singleton!");
return;
}
s = Str(runq->argv->words);
n = 0;
for(t = s;'0'<=*t && *t<='9';t++) n = n*10+*t-'0';
a = runq->argv->next->words;
if(n==0 || *t)
a = copywords(vlook(s)->val, a);
else{
star = vlook("*")->val;
if(star && 1<=n && n<=count(star)){
while(--n) star = star->next;
a = newword(star->word, a);
}
}
poplist();
runq->argv->words = a;
}
void
Xqdol(void)
{
char *s;
word *a;
if(count(runq->argv->words)!=1){
Xerror1("variable name not singleton!");
return;
}
s = Str(runq->argv->words);
a = vlook(s)->val;
poplist();
Pushword(list2str(a));
}
word*
copynwords(word *a, word *tail, int n)
{
word *v, **end;
v = 0;
end = &v;
while(n-- > 0){
*end = newword(a->word, 0);
end = &(*end)->next;
a = a->next;
}
*end = tail;
return v;
}
word*
subwords(word *val, int len, word *sub, word *a)
{
int n, m;
char *s;
if(!sub)
return a;
a = subwords(val, len, sub->next, a);
s = Str(sub);
m = 0;
n = 0;
while('0'<=*s && *s<='9')
n = n*10+ *s++ -'0';
if(*s == '-'){
if(*++s == 0)
m = len - n;
else{
while('0'<=*s && *s<='9')
m = m*10+ *s++ -'0';
m -= n;
}
}
if(n<1 || n>len || m<0)
return a;
if(n+m>len)
m = len-n;
while(--n > 0)
val = val->next;
return copynwords(val, a, m+1);
}
void
Xsub(void)
{
word *a, *v;
char *s;
if(count(runq->argv->next->words)!=1){
Xerror1("variable name not singleton!");
return;
}
s = Str(runq->argv->next->words);
a = runq->argv->next->next->words;
v = vlook(s)->val;
a = subwords(v, count(v), runq->argv->words, a);
poplist();
poplist();
runq->argv->words = a;
}
void
Xcount(void)
{
word *a;
char *s, *t;
int n;
char num[12];
if(count(runq->argv->words)!=1){
Xerror1("variable name not singleton!");
return;
}
s = Str(runq->argv->words);
n = 0;
for(t = s;'0'<=*t && *t<='9';t++) n = n*10+*t-'0';
if(n==0 || *t){
a = vlook(s)->val;
inttoascii(num, count(a));
}
else{
a = vlook("*")->val;
inttoascii(num, a && 1<=n && n<=count(a)?1:0);
}
poplist();
pushword(num);
}
void
Xlocal(void)
{
if(count(runq->argv->words)!=1){
Xerror1("variable name must be singleton\n");
return;
}
runq->local = newvar(Str(runq->argv->words), runq->local);
poplist();
runq->local->val = globlist(runq->argv->words);
runq->local->changed = 1;
runq->argv->words = 0;
poplist();
}
void
Xunlocal(void)
{
var *v = runq->local, *hid;
if(v==0)
panic("Xunlocal: no locals!", 0);
runq->local = v->next;
hid = vlook(v->name);
hid->changed = 1;
free(v->name);
freewords(v->val);
free(v);
}
void
freewords(word *w)
{
word *nw;
while(w){
free(w->word);
nw = w->next;
free(w);
w = nw;
}
}
void
Xfn(void)
{
var *v;
word *a;
int end;
end = runq->code[runq->pc].i;
for(a = globlist(runq->argv->words);a;a = a->next){
v = gvlook(a->word);
if(v->fn)
codefree(v->fn);
v->fn = codecopy(runq->code);
v->pc = runq->pc+2;
v->fnchanged = 1;
}
runq->pc = end;
poplist();
}
void
Xdelfn(void)
{
var *v;
word *a;
for(a = runq->argv->words;a;a = a->next){
v = gvlook(a->word);
if(v->fn)
codefree(v->fn);
v->fn = 0;
v->fnchanged = 1;
}
poplist();
}
char*
concstatus(char *s, char *t)
{
static char v[NSTATUS+1];
int n = strlen(s);
strncpy(v, s, NSTATUS);
if(n<NSTATUS){
v[n]='|';
strncpy(v+n+1, t, NSTATUS-n-1);
}
v[NSTATUS]='\0';
return v;
}
void
Xpipewait(void)
{
char status[NSTATUS+1];
if(runq->pid==-1)
setstatus(concstatus(runq->status, getstatus()));
else{
strncpy(status, getstatus(), NSTATUS);
status[NSTATUS]='\0';
Waitfor(runq->pid, 1);
runq->pid=-1;
setstatus(concstatus(getstatus(), status));
}
}
void
Xrdcmds(void)
{
struct thread *p = runq;
word *prompt;
flush(err);
nerror = 0;
if(flag['s'] && !truestatus())
pfmt(err, "status=%v\n", vlook("status")->val);
if(runq->iflag){
prompt = vlook("prompt")->val;
if(prompt)
promptstr = prompt->word;
else
promptstr="% ";
}
Noerror();
if(yyparse()){
if(!p->iflag || p->eof && !Eintr()){
if(p->cmdfile)
free(p->cmdfile);
closeio(p->cmdfd);
Xreturn(); /* should this be omitted? */
}
else{
if(Eintr()){
pchr(err, '\n');
p->eof = 0;
}
--p->pc; /* go back for next command */
}
}
else{
ntrap = 0; /* avoid double-interrupts during blocked writes */
--p->pc; /* re-execute Xrdcmds after codebuf runs */
start(codebuf, 1, runq->local);
}
freenodes();
}
void
Xerror(char *s)
{
if(strcmp(argv0, "rc")==0 || strcmp(argv0, "/bin/rc")==0)
pfmt(err, "rc: %s: %r\n", s);
else
pfmt(err, "rc (%s): %s: %r\n", argv0, s);
flush(err);
setstatus("error");
while(!runq->iflag) Xreturn();
}
void
Xerror1(char *s)
{
if(strcmp(argv0, "rc")==0 || strcmp(argv0, "/bin/rc")==0)
pfmt(err, "rc: %s\n", s);
else
pfmt(err, "rc (%s): %s\n", argv0, s);
flush(err);
setstatus("error");
while(!runq->iflag) Xreturn();
}
void
setstatus(char *s)
{
setvar("status", newword(s, (word *)0));
}
char*
getstatus(void)
{
var *status = vlook("status");
return status->val?status->val->word:"";
}
int
truestatus(void)
{
char *s;
for(s = getstatus();*s;s++)
if(*s!='|' && *s!='0')
return 0;
return 1;
}
void
Xdelhere(void)
{
Unlink(runq->code[runq->pc++].s);
}
void
Xfor(void)
{
if(runq->argv->words==0){
poplist();
runq->pc = runq->code[runq->pc].i;
}
else{
freelist(runq->local->val);
runq->local->val = runq->argv->words;
runq->local->changed = 1;
runq->argv->words = runq->argv->words->next;
runq->local->val->next = 0;
runq->pc++;
}
}
void
Xglob(void)
{
globlist(runq->argv->words);
}