ref: a00b6bdbfa72a1688a866edf5f825720c9874ada
dir: /sys/src/cmd/rc/simple.c/
/*
* Maybe `simple' is a misnomer.
*/
#include "rc.h"
#include "getflags.h"
#include "exec.h"
#include "io.h"
#include "fns.h"
/*
* Search through the following code to see if we're just going to exit.
*/
int
exitnext(void){
union code *c=&runq->code[runq->pc];
while(c->f==Xpopredir) c++;
return c->f==Xexit;
}
void
Xsimple(void)
{
word *a;
var *v;
struct builtin *bp;
int pid;
a = globlist(runq->argv->words);
if(a==0){
Xerror1("empty argument list");
return;
}
if(flag['x'])
pfmt(err, "%v\n", a); /* wrong, should do redirs */
v = gvlook(a->word);
if(v->fn)
execfunc(v);
else{
if(strcmp(a->word, "builtin")==0){
if(count(a)==1){
pfmt(err, "builtin: empty argument list\n");
setstatus("empty arg list");
poplist();
return;
}
a = a->next;
popword();
}
for(bp = Builtin;bp->name;bp++)
if(strcmp(a->word, bp->name)==0){
(*bp->fnc)();
return;
}
if(exitnext()){
/* fork and wait is redundant */
pushword("exec");
execexec();
}
else{
flush(err);
Updenv(); /* necessary so changes don't go out again */
if((pid = execforkexec()) < 0){
Xerror("try again");
return;
}
/* interrupts don't get us out */
poplist();
while(Waitfor(pid, 1) < 0)
;
}
}
}
struct word nullpath = { "", 0};
void
doredir(redir *rp)
{
if(rp){
doredir(rp->next);
switch(rp->type){
case ROPEN:
if(rp->from!=rp->to){
Dup(rp->from, rp->to);
close(rp->from);
}
break;
case RDUP:
Dup(rp->from, rp->to);
break;
case RCLOSE:
close(rp->from);
break;
}
}
}
word*
searchpath(char *w)
{
word *path;
if(strncmp(w, "/", 1)==0
|| strncmp(w, "#", 1)==0
|| strncmp(w, "./", 2)==0
|| strncmp(w, "../", 3)==0
|| (path = vlook("path")->val)==0)
path=&nullpath;
return path;
}
void
execexec(void)
{
popword(); /* "exec" */
if(runq->argv->words==0){
Xerror1("empty argument list");
return;
}
doredir(runq->redir);
Execute(runq->argv->words, searchpath(runq->argv->words->word));
poplist();
Xexit();
}
void
execfunc(var *func)
{
word *starval;
popword();
starval = runq->argv->words;
runq->argv->words = 0;
poplist();
start(func->fn, func->pc, runq->local);
runq->local = newvar("*", runq->local);
runq->local->val = starval;
runq->local->changed = 1;
}
int
dochdir(char *word)
{
/* report to /dev/wdir if it exists and we're interactive */
if(chdir(word)<0) return -1;
if(flag['i']!=0){
static int wdirfd = -2;
if(wdirfd==-2) /* try only once */
wdirfd = open("/dev/wdir", OWRITE|OCEXEC);
if(wdirfd>=0)
write(wdirfd, word, strlen(word));
}
return 1;
}
void
execcd(void)
{
word *a = runq->argv->words;
word *cdpath;
char *dir;
setstatus("can't cd");
cdpath = vlook("cdpath")->val;
switch(count(a)){
default:
pfmt(err, "Usage: cd [directory]\n");
break;
case 2:
if(a->next->word[0]=='/' || cdpath==0)
cdpath = &nullpath;
for(; cdpath; cdpath = cdpath->next){
if(cdpath->word[0] != '\0')
dir = smprint("%s/%s", cdpath->word,
a->next->word);
else
dir = estrdup(a->next->word);
if(dochdir(dir) >= 0){
if(cdpath->word[0] != '\0' &&
strcmp(cdpath->word, ".") != 0)
pfmt(err, "%s\n", dir);
free(dir);
setstatus("");
break;
}
free(dir);
}
if(cdpath==0)
pfmt(err, "Can't cd %s: %r\n", a->next->word);
break;
case 1:
a = vlook("home")->val;
if(count(a)>=1){
if(dochdir(a->word)>=0)
setstatus("");
else
pfmt(err, "Can't cd %s: %r\n", a->word);
}
else
pfmt(err, "Can't cd -- $home empty\n");
break;
}
poplist();
}
void
execexit(void)
{
switch(count(runq->argv->words)){
default:
pfmt(err, "Usage: exit [status]\nExiting anyway\n");
case 2:
setstatus(runq->argv->words->next->word);
case 1: Xexit();
}
}
void
execshift(void)
{
int n;
word *a;
var *star;
switch(count(runq->argv->words)){
default:
pfmt(err, "Usage: shift [n]\n");
setstatus("shift usage");
poplist();
return;
case 2:
n = atoi(runq->argv->words->next->word);
break;
case 1:
n = 1;
break;
}
star = vlook("*");
for(;n>0 && star->val;--n){
a = star->val->next;
free(star->val->word);
free(star->val);
star->val = a;
star->changed = 1;
}
setstatus("");
poplist();
}
int
mapfd(int fd)
{
redir *rp;
for(rp = runq->redir;rp;rp = rp->next){
switch(rp->type){
case RCLOSE:
if(rp->from==fd)
fd=-1;
break;
case RDUP:
case ROPEN:
if(rp->to==fd)
fd = rp->from;
break;
}
}
return fd;
}
union code rdcmds[4];
void
execcmds(io *f)
{
static int first = 1;
if(first){
rdcmds[0].i = 1;
rdcmds[1].f = Xrdcmds;
rdcmds[2].f = Xreturn;
first = 0;
}
start(rdcmds, 1, runq->local);
runq->cmdfd = f;
runq->iflast = 0;
}
void
execeval(void)
{
char *cmdline;
int len;
if(count(runq->argv->words)<=1){
Xerror1("Usage: eval cmd ...");
return;
}
eflagok = 1;
cmdline = list2str(runq->argv->words->next);
len = strlen(cmdline);
cmdline[len] = '\n';
poplist();
execcmds(opencore(cmdline, len+1));
free(cmdline);
}
union code dotcmds[14];
void
execdot(void)
{
int iflag = 0;
int fd;
list *av;
thread *p = runq;
char *zero, *file;
word *path;
static int first = 1;
if(first){
dotcmds[0].i = 1;
dotcmds[1].f = Xmark;
dotcmds[2].f = Xword;
dotcmds[3].s="0";
dotcmds[4].f = Xlocal;
dotcmds[5].f = Xmark;
dotcmds[6].f = Xword;
dotcmds[7].s="*";
dotcmds[8].f = Xlocal;
dotcmds[9].f = Xrdcmds;
dotcmds[10].f = Xunlocal;
dotcmds[11].f = Xunlocal;
dotcmds[12].f = Xreturn;
first = 0;
}
else
eflagok = 1;
popword();
if(p->argv->words && strcmp(p->argv->words->word, "-i")==0){
iflag = 1;
popword();
}
/* get input file */
if(p->argv->words==0){
Xerror1("Usage: . [-i] file [arg ...]");
return;
}
zero = estrdup(p->argv->words->word);
popword();
fd = -1;
for(path = searchpath(zero); path; path = path->next){
if(path->word[0] != '\0')
file = smprint("%s/%s", path->word, zero);
else
file = estrdup(zero);
fd = open(file, 0);
free(file);
if(fd >= 0)
break;
if(strcmp(file, "/dev/stdin")==0){ /* for sun & ucb */
fd = Dup1(0);
if(fd>=0)
break;
}
}
if(fd<0){
pfmt(err, "%s: ", zero);
setstatus("can't open");
Xerror(".: can't open");
return;
}
/* set up for a new command loop */
start(dotcmds, 1, (struct var *)0);
pushredir(RCLOSE, fd, 0);
runq->cmdfile = zero;
runq->cmdfd = openfd(fd);
runq->iflag = iflag;
runq->iflast = 0;
/* push $* value */
pushlist();
runq->argv->words = p->argv->words;
/* free caller's copy of $* */
av = p->argv;
p->argv = av->next;
free(av);
/* push $0 value */
pushlist();
pushword(zero);
ndot++;
}
void
execflag(void)
{
char *letter, *val;
switch(count(runq->argv->words)){
case 2:
setstatus(flag[(uchar)runq->argv->words->next->word[0]]?"":"flag not set");
break;
case 3:
letter = runq->argv->words->next->word;
val = runq->argv->words->next->next->word;
if(strlen(letter)==1){
if(strcmp(val, "+")==0){
flag[(uchar)letter[0]] = flagset;
break;
}
if(strcmp(val, "-")==0){
flag[(uchar)letter[0]] = 0;
break;
}
}
default:
Xerror1("Usage: flag [letter] [+-]");
return;
}
poplist();
}
void
execwhatis(void){ /* mildly wrong -- should fork before writing */
word *a, *b, *path;
var *v;
struct builtin *bp;
char *file;
struct io out[1];
int found, sep;
a = runq->argv->words->next;
if(a==0){
Xerror1("Usage: whatis name ...");
return;
}
setstatus("");
out->fd = mapfd(1);
out->bufp = out->buf;
out->ebuf = &out->buf[NBUF];
out->strp = 0;
for(;a;a = a->next){
v = vlook(a->word);
if(v->val){
pfmt(out, "%s=", a->word);
if(v->val->next==0)
pfmt(out, "%q\n", v->val->word);
else{
sep='(';
for(b = v->val;b && b->word;b = b->next){
pfmt(out, "%c%q", sep, b->word);
sep=' ';
}
pfmt(out, ")\n");
}
found = 1;
}
else
found = 0;
v = gvlook(a->word);
if(v->fn)
pfmt(out, "fn %q %s\n", v->name, v->fn[v->pc-1].s);
else{
for(bp = Builtin;bp->name;bp++)
if(strcmp(a->word, bp->name)==0){
pfmt(out, "builtin %s\n", a->word);
break;
}
if(!bp->name){
for(path = searchpath(a->word); path;
path = path->next){
if(path->word[0] != '\0')
file = smprint("%s/%s",
path->word, a->word);
else
file = estrdup(a->word);
if(Executable(file)){
pfmt(out, "%s\n", file);
free(file);
break;
}
free(file);
}
if(!path && !found){
pfmt(err, "%s: not found\n", a->word);
setstatus("not found");
}
}
}
}
poplist();
flush(err);
}
void
execwait(void)
{
switch(count(runq->argv->words)){
default:
Xerror1("Usage: wait [pid]");
return;
case 2:
Waitfor(atoi(runq->argv->words->next->word), 0);
break;
case 1:
Waitfor(-1, 0);
break;
}
poplist();
}