diff options
Diffstat (limited to 'src/cmd/rc/havefork.c')
| -rw-r--r-- | src/cmd/rc/havefork.c | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/src/cmd/rc/havefork.c b/src/cmd/rc/havefork.c new file mode 100644 index 00000000..e81046d6 --- /dev/null +++ b/src/cmd/rc/havefork.c @@ -0,0 +1,212 @@ +#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 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: + pushredir(ROPEN, null, 0); + 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; + } +} + +/* + * Who should wait for the exit from the fork? + */ +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; + } +} + +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; +} |