ref: 694039a3792bd62ac8e086ac710dddd553333bb6
dir: /net.c/
#include <u.h> #include <libc.h> #include <thread.h> #include <draw.h> #include "dat.h" #include "fns.h" int lport = 17996; char *netmtpt = "/net"; typedef struct Con Con; enum{ Ncon = Nteam * 4, Nbuf = 4096, }; struct Con{ int fd; Team *t; }; static Con con[Ncon]; static Channel *lc; static uchar cbuf[Nbuf], *cbufp = cbuf; static void closenet(Con *c) { close(c->fd); c->fd = -1; } static void flushcmd(Con *c) { int n; if((n = cbufp - cbuf) == 0) return; if(write(c->fd, cbuf, n) != n){ fprint(2, "flushcmd: %r\n"); closenet(c); } cbufp = cbuf; } static void writecmd(Con *c, char *fmt, va_list a) { union{ uchar u[4]; s32int l; } u; for(;;){ if(cbufp - cbuf > sizeof(cbuf) - 4) flushcmd(c); switch(*fmt++){ default: sysfatal("unknown format %c", fmt[-1]); case 0: return; case 'u': u.l = va_arg(a, s32int); memcpy(cbufp, u.u, sizeof u.u); cbufp += sizeof u.u; } } } static void packcmd(Con *c, char *fmt, ...) { va_list a; va_start(a, fmt); writecmd(c, fmt, a); va_end(a); } void flushcl(void) { flushcmd(con); } void packcl(char *fmt, ...) { va_list a; va_start(a, fmt); packcmd(con, fmt, a); va_end(a); } static void writenet(void) { Con *c; for(c=con; c<con+nelem(con); c++){ if(c->fd < 0) continue; } } static void execbuf(Con *c, uchar *p, uchar *e) { int n; while(p < e){ n = *p++; switch(n){ case Tquit: closenet(c); return; } } } static void readnet(void) { int n, m; Con *c; uchar buf[Nbuf], *p; for(c=con; c<con+nelem(con); c++){ if(c->fd < 0) continue; for(m=sizeof buf, p=buf; (n = flen(c->fd)) > 1 && n <= m; m-=n, p+=n){ if(read(c->fd, p, n) != n){ fprint(2, "readnet: %r\n"); closenet(c); break; } } execbuf(c, buf, p); } } void stepnet(void) { int fd; if(nbrecv(lc, &fd) > 0){ /* FIXME: add to observers (team 0) */ } readnet(); writenet(); } void joinnet(char *sys) { char s[128]; snprint(s, sizeof s, "%s/tcp!%s!%d", netmtpt, sys != nil ? sys : sysname(), lport); if((con[0].fd = dial(s, nil, nil, nil)) < 0) sysfatal("dial: %r"); } static int regnet(int lfd, char *ldir) { Con *c; for(c=con; c<con+nelem(con); c++) if(c->fd < 0) break; if(c == con + nelem(con)) return reject(lfd, ldir, "no more open slots"); c->fd = accept(lfd, ldir); return c->fd; } static void lproc(void *) { int fd, lfd; char adir[40], ldir[40], data[100]; snprint(data, sizeof data, "%s/tcp!*!%d", netmtpt, lport); if(announce(data, adir) < 0) sysfatal("announce: %r"); for(;;){ if((lfd = listen(adir, ldir)) < 0 || (fd = regnet(lfd, ldir)) < 0 || close(lfd) < 0 || send(lc, &fd) < 0) break; } } void listennet(void) { Con *c; for(c=con; c<con+nelem(con); c++) c->fd = -1; if((lc = chancreate(sizeof(int), 0)) == nil) sysfatal("chancreate: %r"); if(proccreate(lproc, nil, 8192) < 0) sysfatal("proccreate: %r"); }