tfix wait - plan9port - [fork] Plan 9 from user space
HTML git clone git://src.adamsgaard.dk/plan9port
DIR Log
DIR Files
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DIR README
DIR LICENSE
---
DIR commit 4b241872ef56389e6bcf4ab602cd52989cf3151d
DIR parent bd1b0cc17e58f8135fa0888cdb2d4fac61f85bce
HTML Author: rsc <devnull@localhost>
Date: Mon, 26 Mar 2007 14:26:32 +0000
fix wait
Diffstat:
M src/cmd/rc/fns.h | 4 ++++
M src/cmd/rc/havefork.c | 51 +++++++++++++++++++++++++++++--
D src/cmd/rc/havep9p.c | 246 -------------------------------
M src/cmd/rc/mkfile | 2 +-
M src/cmd/rc/plan9ish.c | 45 ++++++++++++++++++++++++++++++-
5 files changed, 97 insertions(+), 251 deletions(-)
---
DIR diff --git a/src/cmd/rc/fns.h b/src/cmd/rc/fns.h
t@@ -22,6 +22,7 @@ void Updenv(void);
void Vinit(void);
int Waitfor(int, int);
long Write(int, char*, long);
+void addwaitpid(int);
int advance(void);
int back(int);
void cleanhere(char*);
t@@ -30,10 +31,12 @@ int compile(tree*);
char * list2str(word*);
int count(word*);
void deglob(char*);
+void delwaitpid(int);
void dotrap(void);
void freenodes(void);
void freewords(word*);
void globlist(void);
+int havewaitpid(int);
int idchr(int);
void inttoascii(char*, long);
void kinit(void);
t@@ -41,6 +44,7 @@ int mapfd(int);
int match(char*, char*, int);
int matchfn(char*, char*);
char** mkargv(word*);
+void clearwaitpids(void);
void panic(char*, int);
void pathinit(void);
void poplist(void);
DIR diff --git a/src/cmd/rc/havefork.c b/src/cmd/rc/havefork.c
t@@ -1,3 +1,9 @@
+#include <u.h>
+#include <signal.h>
+#if defined(PLAN9PORT) && defined(__sun__)
+# define BSD_COMP /* sigh. for TIOCNOTTY */
+#endif
+#include <sys/ioctl.h>
#include "rc.h"
#include "getflags.h"
#include "exec.h"
t@@ -10,6 +16,7 @@ void
Xasync(void)
{
int null = open("/dev/null", 0);
+ int tty;
int pid;
char npid[10];
if(null<0){
t@@ -22,11 +29,39 @@ Xasync(void)
Xerror("try again");
break;
case 0:
- pushredir(ROPEN, null, 0);
+ clearwaitpids();
+ /*
+ * I don't know what the right thing to do here is,
+ * so this is all experimentally determined.
+ * If we just dup /dev/null onto 0, then running
+ * ssh foo & will reopen /dev/tty, try to read a password,
+ * get a signal, and repeat, in a tight loop, forever.
+ * Arguably this is a bug in ssh (it behaves the same
+ * way under bash as under rc) but I'm fixing it here
+ * anyway. If we dissociate the process from the tty,
+ * then it won't be able to open /dev/tty ever again.
+ * The SIG_IGN on SIGTTOU makes writing the tty
+ * (via fd 1 or 2, for example) succeed even though
+ * our pgrp is not the terminal's controlling pgrp.
+ */
+ if((tty = open("/dev/tty", OREAD)) >= 0){
+ /*
+ * Should make reads of tty fail, writes succeed.
+ */
+ signal(SIGTTIN, SIG_IGN);
+ signal(SIGTTOU, SIG_IGN);
+ ioctl(tty, TIOCNOTTY);
+ close(tty);
+ }
+ if(isatty(0))
+ pushredir(ROPEN, null, 0);
+ else
+ close(null);
start(runq->code, runq->pc+1, runq->local);
runq->ret = 0;
break;
default:
+ addwaitpid(pid);
close(null);
runq->pc = runq->code[runq->pc].i;
inttoascii(npid, pid);
t@@ -52,12 +87,14 @@ Xpipe(void)
Xerror("try again");
break;
case 0:
+ clearwaitpids();
start(p->code, pc+2, runq->local);
runq->ret = 0;
close(pfd[PRD]);
pushredir(ROPEN, pfd[PWR], lfd);
break;
default:
+ addwaitpid(forkid);
start(p->code, p->code[pc].i, runq->local);
close(pfd[PWR]);
pushredir(ROPEN, pfd[PRD], rfd);
t@@ -93,11 +130,13 @@ Xbackq(void)
close(pfd[PWR]);
return;
case 0:
+ clearwaitpids();
close(pfd[PRD]);
start(runq->code, runq->pc+1, runq->local);
pushredir(ROPEN, pfd[PWR], 1);
return;
default:
+ addwaitpid(pid);
close(pfd[PWR]);
f = openfd(pfd[PRD]);
s = wd;
t@@ -134,7 +173,7 @@ void
Xpipefd(void)
{
struct thread *p = runq;
- int pc = p->pc;
+ int pc = p->pc, pid;
char name[40];
int pfd[2];
int sidefd, mainfd;
t@@ -150,17 +189,19 @@ Xpipefd(void)
sidefd = pfd[PRD];
mainfd = pfd[PWR];
}
- switch(fork()){
+ switch(pid = fork()){
case -1:
Xerror("try again");
break;
case 0:
+ clearwaitpids();
start(p->code, pc+2, runq->local);
close(mainfd);
pushredir(ROPEN, sidefd, p->code[pc].i==READ?1:0);
runq->ret = 0;
break;
default:
+ addwaitpid(pid);
close(sidefd);
pushredir(ROPEN, mainfd, mainfd); /* isn't this a noop? */
strcpy(name, Fdprefix);
t@@ -180,10 +221,12 @@ Xsubshell(void)
Xerror("try again");
break;
case 0:
+ clearwaitpids();
start(runq->code, runq->pc+1, runq->local);
runq->ret = 0;
break;
default:
+ addwaitpid(pid);
Waitfor(pid, 1);
runq->pc = runq->code[runq->pc].i;
break;
t@@ -201,6 +244,7 @@ execforkexec(void)
case -1:
return -1;
case 0:
+ clearwaitpids();
pushword("exec");
execexec();
strcpy(buf, "can't exec: ");
t@@ -208,5 +252,6 @@ execforkexec(void)
errstr(buf+n, ERRMAX-n);
Exit(buf);
}
+ addwaitpid(pid);
return pid;
}
DIR diff --git a/src/cmd/rc/havep9p.c b/src/cmd/rc/havep9p.c
t@@ -1,246 +0,0 @@
-#include <u.h>
-#include <signal.h>
-#if defined(PLAN9PORT) && defined(__sun__)
-# define BSD_COMP /* sigh. for TIOCNOTTY */
-#endif
-#include <sys/ioctl.h>
-#include "rc.h"
-#include "getflags.h"
-#include "exec.h"
-#include "io.h"
-#include "fns.h"
-
-int havefork = 1;
-
-void
-Xasync(void)
-{
- int null=open("/dev/null", 0);
- int tty;
- int pid;
- char npid[10];
- if(null<0){
- Xerror("Can't open /dev/null\n");
- return;
- }
- switch(pid=rfork(RFFDG|RFPROC|RFNOTEG)){
- case -1:
- close(null);
- Xerror("try again");
- break;
- case 0:
- /*
- * I don't know what the right thing to do here is,
- * so this is all experimentally determined.
- * If we just dup /dev/null onto 0, then running
- * ssh foo & will reopen /dev/tty, try to read a password,
- * get a signal, and repeat, in a tight loop, forever.
- * Arguably this is a bug in ssh (it behaves the same
- * way under bash as under rc) but I'm fixing it here
- * anyway. If we dissociate the process from the tty,
- * then it won't be able to open /dev/tty ever again.
- * The SIG_IGN on SIGTTOU makes writing the tty
- * (via fd 1 or 2, for example) succeed even though
- * our pgrp is not the terminal's controlling pgrp.
- */
- if((tty=open("/dev/tty", OREAD)) >= 0){
- /*
- * Should make reads of tty fail, writes succeed.
- */
- signal(SIGTTIN, SIG_IGN);
- signal(SIGTTOU, SIG_IGN);
- ioctl(tty, TIOCNOTTY);
- close(tty);
- }
- if(isatty(0))
- pushredir(ROPEN, null, 0);
- else
- close(null);
- start(runq->code, runq->pc+1, runq->local);
- runq->ret=0;
- break;
- default:
- close(null);
- runq->pc=runq->code[runq->pc].i;
- inttoascii(npid, pid);
- setvar("apid", newword(npid, (word *)0));
- break;
- }
-}
-
-void
-Xpipe(void)
-{
- struct thread *p = runq;
- int pc = p->pc, forkid;
- int lfd = p->code[pc++].i;
- int rfd = p->code[pc++].i;
- int pfd[2];
-
- if(pipe(pfd)<0){
- Xerror("can't get pipe");
- return;
- }
- switch(forkid=fork()){
- case -1:
- Xerror("try again");
- break;
- case 0:
- start(p->code, pc+2, runq->local);
- runq->ret=0;
- close(pfd[PRD]);
- pushredir(ROPEN, pfd[PWR], lfd);
- break;
- default:
- start(p->code, p->code[pc].i, runq->local);
- close(pfd[PWR]);
- pushredir(ROPEN, pfd[PRD], rfd);
- p->pc=p->code[pc+1].i;
- p->pid=forkid;
- break;
- }
-}
-
-void
-Xbackq(void)
-{
- char wd[8193];
- int c;
- char *s, *ewd = &wd[8192], *stop;
- struct io *f;
- var *ifs = vlook("ifs");
- word *v, *nextv;
- int pfd[2];
- int pid;
-
- stop = ifs->val?ifs->val->word:"";
- if(pipe(pfd)<0){
- Xerror("can't make pipe");
- return;
- }
- switch(pid = fork()){
- case -1: Xerror("try again");
- close(pfd[PRD]);
- close(pfd[PWR]);
- return;
- case 0:
- close(pfd[PRD]);
- start(runq->code, runq->pc+1, runq->local);
- pushredir(ROPEN, pfd[PWR], 1);
- return;
- default:
- close(pfd[PWR]);
- f=openfd(pfd[PRD]);
- s=wd;
- v=0;
- while((c=rchr(f))!=EOF){
- if(strchr(stop, c) || s==ewd){
- if(s!=wd){
- *s='\0';
- v=newword(wd, v);
- s=wd;
- }
- }
- else *s++=c;
- }
- if(s!=wd){
- *s='\0';
- v=newword(wd, v);
- }
- closeio(f);
- Waitfor(pid, 0);
- /* v points to reversed arglist -- reverse it onto argv */
- while(v){
- nextv=v->next;
- v->next=runq->argv->words;
- runq->argv->words=v;
- v=nextv;
- }
- runq->pc=runq->code[runq->pc].i;
- return;
- }
-}
-
-/*
- * Who should wait for the exit from the fork?
- */
-void
-Xpipefd(void)
-{
- struct thread *p=runq;
- int pc=p->pc;
- char name[40];
- int pfd[2];
- int sidefd, mainfd;
- if(pipe(pfd)<0){
- Xerror("can't get pipe");
- return;
- }
- if(p->code[pc].i==READ){
- sidefd=pfd[PWR];
- mainfd=pfd[PRD];
- }
- else{
- sidefd=pfd[PRD];
- mainfd=pfd[PWR];
- }
- switch(fork()){
- case -1:
- Xerror("try again");
- break;
- case 0:
- start(p->code, pc+2, runq->local);
- close(mainfd);
- pushredir(ROPEN, sidefd, p->code[pc].i==READ?1:0);
- runq->ret=0;
- break;
- default:
- close(sidefd);
- pushredir(ROPEN, mainfd, mainfd); /* isn't this a noop? */
- strcpy(name, Fdprefix);
- inttoascii(name+strlen(name), mainfd);
- pushword(name);
- p->pc=p->code[pc+1].i;
- break;
- }
-}
-
-void
-Xsubshell(void)
-{
- int pid;
- switch(pid=fork()){
- case -1:
- Xerror("try again");
- break;
- case 0:
- start(runq->code, runq->pc+1, runq->local);
- runq->ret=0;
- break;
- default:
- Waitfor(pid, 1);
- runq->pc=runq->code[runq->pc].i;
- break;
- }
-}
-
-int
-execforkexec(void)
-{
- int pid;
- int n;
- char buf[ERRMAX];
-
- switch(pid = fork()){
- case -1:
- return -1;
- case 0:
- pushword("exec");
- execexec();
- strcpy(buf, "can't exec: ");
- n = strlen(buf);
- errstr(buf+n, ERRMAX-n);
- Exit(buf);
- }
- return pid;
-}
DIR diff --git a/src/cmd/rc/mkfile b/src/cmd/rc/mkfile
t@@ -20,7 +20,7 @@ OFILES=\
var.$O\
y.tab.$O\
plan9ish.$O\
- havep9p.$O\
+ havefork.$O\
HFILES=\
rc.h\
DIR diff --git a/src/cmd/rc/plan9ish.c b/src/cmd/rc/plan9ish.c
t@@ -199,7 +199,10 @@ int Waitfor(int pid, int unused0){
Waitmsg *w;
char errbuf[ERRMAX];
+ if(pid >= 0 && !havewaitpid(pid))
+ return 0;
while((w = wait()) != nil){
+ delwaitpid(w->pid);
if(w->pid==pid){
if(strncmp(w->msg, "signal: ", 8) == 0)
fprint(mapfd(2), "%d: %s\n", w->pid, w->msg);
t@@ -217,7 +220,7 @@ int Waitfor(int pid, int unused0){
free(w);
}
- errstr(errbuf, sizeof errbuf);
+ rerrstr(errbuf, sizeof errbuf);
if(strcmp(errbuf, "interrupted")==0) return -1;
return 0;
}
t@@ -559,3 +562,43 @@ exitcode(char *msg)
n = 1;
return n;
}
+
+int *waitpids;
+int nwaitpids;
+
+void
+addwaitpid(int pid)
+{
+ waitpids = realloc(waitpids, (nwaitpids+1)*sizeof waitpids[0]);
+ if(waitpids == 0)
+ panic("Can't realloc %d waitpids", nwaitpids+1);
+ waitpids[nwaitpids++] = pid;
+}
+
+void
+delwaitpid(int pid)
+{
+ int r, w;
+
+ for(r=w=0; r<nwaitpids; r++)
+ if(waitpids[r] != pid)
+ waitpids[w++] = waitpids[r];
+ nwaitpids = w;
+}
+
+void
+clearwaitpids(void)
+{
+ nwaitpids = 0;
+}
+
+int
+havewaitpid(int pid)
+{
+ int i;
+
+ for(i=0; i<nwaitpids; i++)
+ if(waitpids[i] == pid)
+ return 1;
+ return 0;
+}