diff options
Diffstat (limited to 'sys/cmd/rc/exec.c')
| -rw-r--r-- | sys/cmd/rc/exec.c | 331 |
1 files changed, 221 insertions, 110 deletions
diff --git a/sys/cmd/rc/exec.c b/sys/cmd/rc/exec.c index 217f7ee..f9af866 100644 --- a/sys/cmd/rc/exec.c +++ b/sys/cmd/rc/exec.c @@ -10,6 +10,12 @@ struct Builtin{ void (*func)(void); }; +struct State { + int async; +}; + +static struct State state; + // ----------------------------------------------------------------------- // globals @@ -138,6 +144,14 @@ path(char *w) static inline void +undoredirs(void) +{ + while(runner->redir.end != runner->redir.start) + Xpopredir(); +} + +static inline +void defaultsignal(void) { signal(SIGINT, SIG_DFL); @@ -150,15 +164,50 @@ defaultsignal(void) static inline void -setpid(int pid) +setpid(Thread *job, int pid) +{ + job->pid = pid; + if(job->pgid <= 0){ + job->pgid = pid; + addjob(job); + } + + setpgid(pid, job->pgid); +} + +/* fork/execute helpers */ + +static inline +void +initchild(Thread *job, int fg) { - runner->pid = pid; - if(runner->pgid <= 0){ - runner->pgid = runner->pid; - addjob(runner); + int pid = getpid(); + setpid(job, pid); + + if(job->flag.user){ + if(fg) + tcsetpgrp(0, job->pgid); + else + job->flag.user = 0; + defaultsignal(); } - setpgid(pid, runner->pgid); + clearwait(job); +} + +static inline +void +initparent(Thread *job, int pid, int fg) +{ + setpid(job, pid); + + if(job->flag.user){ + if(!fg){ + tcsetpgrp(0, job->pgid); + job->flag.user = 0; + } + } + addwait(job, pid); } static @@ -171,6 +220,7 @@ xx(void) return; } + redirect(runner->redir.end); execute(runner->args->word, path(runner->args->word->str)); poplist(); } @@ -180,29 +230,20 @@ int xforkx(void) { int n, pid; - char buf[ERRMAX]; switch(pid=fork()){ case -1: + Xerror("try again\n"); return -1; case 0: // child - clearwait(runner); - runner->link = nil; - - if(shell.interactive){ - setpid(getpid()); - tcsetpgrp(0, runner->pgid); - defaultsignal(); - } + initchild(runner, 1); pushword("exec"); xx(); - exit(2); // NOTE: xx does not return! - /*unreachable*/ + exit(2); // NOTE: unreachable: xx does not return default: // parent - addwait(runner, pid); - setpid(pid); // ensure the state matches for parent and child + initparent(runner, pid, 0); return pid; } @@ -217,15 +258,14 @@ pushredir(int type, int from, int to) r->type = type; r->from = from; r->to = to; - r->link = runner->redir; - runner->redir = r; + r->link = runner->redir.end, runner->redir.end = r; } /* byte code */ static void -run(Code *c, int pc, Var *local, int keeppid) +run(Code *c, int pc, Var *local, int inherit) { Thread *new = emalloc(sizeof(*new)); @@ -237,10 +277,17 @@ run(Code *c, int pc, Var *local, int keeppid) new->args = nil; new->local = local; - new->redir = nil; - new->flag.i = 0; - new->flag.eof = 0; + new->flag.eof = 0; + if(runner){ + new->pid = runner->pid; + new->flag.user = runner->flag.user; + new->redir.end = new->redir.start = runner->redir.end; + }else{ + new->pid = shell.pid; + new->flag.user = shell.interactive; + new->redir.end = new->redir.start = nil; + } new->wait.status = 0; new->wait.len = 0; @@ -248,14 +295,14 @@ run(Code *c, int pc, Var *local, int keeppid) new->wait.on = nil; new->status = 0; - if(keeppid) - new->pgid = runner->pgid, new->pid = runner->pid; + if(inherit) + new->pgid = runner->pgid; else - new->pgid = new->pid = -1; + new->pgid = -1; new->line = 0; - new->link = runner; - new->next = nil; + new->caller = runner; + new->link = nil; runner = new; } @@ -354,9 +401,7 @@ xdot(void) } if(fd<0){ - print(shell.err, "%s: ", base); - //setstatus("can't open"); - Xerror(".: can't open\n"); + print(shell.err, "failed open: %s: ", base); return; } /* set up for a new command loop */ @@ -432,7 +477,7 @@ xjob(void) int i; Thread *job; - for(i=0, job = shell.jobs; job; job = job->next, i++) + for(i=0, job = shell.jobs; job; job = job->link, i++) report(job,i); poplist(); @@ -454,16 +499,16 @@ xfg(void) } i = atoi(runner->args->word->str); - popword(); // [jobid] + popword(); // [pid|num] - for(job=shell.jobs; i > 0; job=job->next, --i) + for(job=shell.jobs; i > 0; job=job->link, --i) ; poplist(); // this goes here? wakeup(job); - job->link = runner, runner = job; // XXX: can this leave zombies? foreground(job, 1); + job->caller = runner, runner = job; // XXX: can this leave zombies? } void @@ -493,6 +538,7 @@ xboot(int argc, char *argv[]) bootstrap[i].i = 0; run(bootstrap, 1, nil, 0); + runner->pid = runner->pgid = shell.pid; pushlist(); // prime bootstrap argv argv0 = strdup(argv[0]); @@ -516,54 +562,6 @@ Xmark(void) } void -Xerror(char *msg) -{ - print(shell.err, "rc: %s", msg); - flush(shell.err); - while(!runner->flag.i) - Xreturn(); -} - -void -Xreturn(void) -{ - Thread *run = runner; - - switch(run->wait.status){ - /* - * If our job is still running we must: - * 1. move program one step back to rerun Xreturn upon recall - * 2. return to our calling thread - * 3. don't free! - */ - case Prun: case Pstop: - run->code.i--; - runner = run->link; - return; - /* - * If our job has finished: - * 1. remove from our list - * 2. continue to clean up its memory - */ - case Pdone: - deljob(run); - /* fallthrough */ - default: - ; - } - - while(run->args) - poplist(); - freecode(run->code.exe); - efree(run->wait.on); - - runner = run->link; - efree(run); - if(!runner) - exit(0); -} - -void Xword(void) { pushword(runner->code.exe[runner->code.i++].s); @@ -703,21 +701,18 @@ Xasync(void) Xerror("fork failed: try again"); break; - case 0: // child - clearwait(runner); + case 0: // child in background + initchild(runner,0); pushredir(Ropen, null, 0); - if(shell.interactive){ // NOTE: this needs to read off its caller's interactivity - setpid(getpid()); - defaultsignal(); - } - run(runner->code.exe, runner->code.i+1, runner->local, 1); - runner->link = nil; + + run(runner->code.exe, runner->code.i+1, runner->local, 0); + runner->caller = nil; + runner->flag.user = 0; break; - default: // parent + default: // parent in foreground + initparent(runner,pid,1); close(null); - setpid(pid); - addwait(runner, pid); runner->code.i = runner->code.exe[runner->code.i].i; /* jump to end of async command */ /* don't wait: continue running */ @@ -727,33 +722,80 @@ Xasync(void) void Xsubshell(void) { - int pid; + int pid, user; + user = runner->flag.user; switch(pid=fork()){ case -1: Xerror("fork failed: try again"); break; case 0: // child - clearwait(runner); - if(shell.interactive){ // NOTE: this needs to read off its caller's interactivity - setpid(getpid()); - tcsetpgrp(0, runner->pgid); - defaultsignal(); - } + initchild(runner, 1); run(runner->code.exe, runner->code.i+1, runner->local, 1); - runner->link = nil; + runner->caller = nil; break; default: // parent - setpid(pid); - addwait(runner, pid); - waitfor(runner, pid); // wait until child finishes + initparent(runner, pid, 0); // relinquish control + waitfor(runner, pid); // wait until child finishes + if(user){ + tcsetpgrp(0, shell.pid); + runner->flag.user = 1; // take control + } + runner->code.i = runner->code.exe[runner->code.i].i; // jump to end of subshell command and continue execution } } +void +Xpipewait(void) +{ + foreground(runner, 0); +} + +void +Xpipe(void) +{ + Thread *orig; + int pc, pid, lfd, rfd, pfd[2]; + + orig = runner; + pc = orig->code.i; + lfd = orig->code.exe[pc++].i; + rfd = orig->code.exe[pc++].i; + + if(pipe(pfd)<0){ + Xerror("can't get pipe\n"); + return; + } + + switch(pid=fork()){ + case -1: + Xerror("try again"); + break; + case 0: // child + initchild(runner,1); + + /* child 0 (writer) forked process */ + run(runner->code.exe, pc+2, runner->local, 0); + runner->caller = nil; + close(pfd[0]); + pushredir(Ropen, pfd[1], lfd); + break; + + default: // parent + initparent(runner,pid,0); + + /* child 1 (reader) subprocess*/ + run(runner->code.exe, runner->code.exe[pc].i, runner->local, 0); + + close(pfd[1]); + pushredir(Ropen, pfd[0], rfd); + break; + } +} void Xbasic(void) @@ -783,6 +825,7 @@ Xbasic(void) } /* if we are here then it's an external command */ + // TODO: check for if we will exit, don't need to fork, just exec // run the external command if((pid = xforkx()) < 0) { @@ -790,9 +833,6 @@ Xbasic(void) return; } - if(!shell.interactive) - waitall(runner); - foreground(runner, 0); // waits for child poplist(); } @@ -865,7 +905,78 @@ Xbang(void) } void +Xpopredir(void) +{ + Redir *r = runner->redir.end; + if(!r) + fatal("attempted to pop a nil redir\n"); + + runner->redir.end = runner->redir.end->link; + if(r->type==Ropen) + close(r->from); + + efree(r); +} + +void +Xreturn(void) +{ + Thread *curr = runner; + + switch(curr->wait.status){ + /* + * If our job is still running or suspended we must: + * 1. move program one step back to rerun Xreturn upon recall + * 2. return to our calling thread + * 3. don't free! + */ + case Prun: + report(curr, 0); + curr->flag.user = 0; + case Pstop: + curr->code.i--; + runner = curr->caller; + curr->caller = nil; // detach job + return; + /* + * If our job has finished: + * 1. remove from our list + * 2. continue to clean up its memory + */ + case Pdone: + deljob(curr); + /* fallthrough */ + default: + ; + } + + undoredirs(); + + while(curr->args) + poplist(); + freecode(curr->code.exe); + efree(curr->wait.on); + + runner = curr->caller; + efree(curr); + if(!runner) + exit(0); +} + + + +void Xexit(void) { exit(runner->status); } + +void +Xerror(char *msg) +{ + print(shell.err, "rc: %s", msg); + flush(shell.err); + while(!runner->flag.user) + Xreturn(); +} + |