ref: cbe4b116989c0bfec49b9ae7a1d9a85ead6648ae
dir: /sys/src/libthread/main.c/
#include <u.h> #include <libc.h> #include <thread.h> #include "threadimpl.h" extern void (*_sysfatal)(char*, va_list); extern void (*__assert)(char*); int mainstacksize; static jmp_buf mainjmp; static int mainargc; static void mainlauncher(void *arg) { threadmain(mainargc, arg); threadexits("threadmain"); } void main(int argc, char **argv) { rfork(RFREND); //_threaddebuglevel = (DBGSCHED|DBGCHAN|DBGREND)^~0; _threadprocp = privalloc(); _qlockinit(_threadrendezvous); _sysfatal = _threadsysfatal; __assert = _threadassert; notify(_threadnote); if(mainstacksize == 0) mainstacksize = 8*1024; mainargc = argc; _threadsetproc(_newproc(mainlauncher, argv, mainstacksize, "threadmain", 0, 0)); setjmp(mainjmp); _schedinit(); abort(); /* not reached */ } static void efork(Execargs *e) { char buf[ERRMAX]; _threaddebug(DBGEXEC, "_schedexec %s", e->prog); close(e->fd[0]); exec(e->prog, e->args); _threaddebug(DBGEXEC, "_schedexec failed: %r"); rerrstr(buf, sizeof buf); if(buf[0]=='\0') strcpy(buf, "exec failed"); write(e->fd[1], buf, strlen(buf)); _exits(buf); } int _schedexec(Execargs *e) { int pid, flag; flag = (_threadwaitchan == nil) ? RFNOWAIT : 0; switch(pid = rfork(RFREND|RFNOTEG|RFFDG|RFMEM|RFPROC|flag)){ case 0: efork(e); default: return pid; } } int _schedfork(Proc *p) { int pid; switch(pid = rfork(RFPROC|RFMEM|RFNOWAIT|p->rforkflag)){ case 0: _threadsetproc(p); longjmp(mainjmp, 1); default: return pid; } } void _schedexit(Proc *p) { char ex[ERRMAX]; utfecpy(ex, ex+sizeof ex, p->exitstr); free(p); _exits(ex); } void _schedexecwait(void) { int pid; Channel *c; Proc *p; Thread *t; Waitmsg *w; p = _threadgetproc(); t = p->thread; pid = t->ret; _threaddebug(DBGEXEC, "_schedexecwait %d", t->ret); rfork(RFCFDG); for(;;){ w = wait(); if(w == nil) break; if(w->pid == pid) break; free(w); } if(w != nil){ if((c = _threadwaitchan) != nil) sendp(c, w); else free(w); } threadexits("procexec"); }