X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/6fb0204d71beff637638ef52978df0e8f58453d7..e6a8d8720982ba6b6e58c71ee002eab1b222e6ca:/src/gras/Transport/rl_transport.c diff --git a/src/gras/Transport/rl_transport.c b/src/gras/Transport/rl_transport.c index 0a702e2dcd..254e1876ee 100644 --- a/src/gras/Transport/rl_transport.c +++ b/src/gras/Transport/rl_transport.c @@ -12,6 +12,9 @@ #include "gras/Transport/transport_private.h" XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(gras_trp); +/* check transport_private.h for an explanation of this variable */ +gras_socket_t _gras_lastly_selected_socket = NULL; + /** * gras_trp_select: * @@ -19,7 +22,6 @@ XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(gras_trp); * * if timeout<0, we ought to implement the adaptative timeout (FIXME) * - * if timeout=0, do not wait for new message, only handle the ones already there. * * if timeout>0 and no message there, wait at most that amount of time before giving up. */ @@ -37,29 +39,37 @@ gras_socket_t gras_trp_select(double timeout) { with this tiny optimisation on BillWare */ fd_set FDS; int ready; /* return of select: number of socket ready to be serviced */ - int fd_setsize; /* FD_SETSIZE not always defined. Get this portably */ + static int fd_setsize=-1; /* FD_SETSIZE not always defined. Get this portably */ gras_socket_t sock_iter; /* iterating over all sockets */ int cursor; /* iterating over all sockets */ - - /* Compute FD_SETSIZE */ + /* Check whether there is more data to read from the socket we selected last time. + This can happen with tcp buffered sockets since we try to get as much data as we can for them */ + if (_gras_lastly_selected_socket && _gras_lastly_selected_socket->moredata) { + VERB0("Returning _gras_lastly_selected_socket since there is more data on it"); + return _gras_lastly_selected_socket; + } + + /* Compute FD_SETSIZE on need */ + if (fd_setsize < 0) { #ifdef HAVE_SYSCONF - fd_setsize = sysconf( _SC_OPEN_MAX ); + fd_setsize = sysconf( _SC_OPEN_MAX ); #else # ifdef HAVE_GETDTABLESIZE - fd_setsize = getdtablesize(); + fd_setsize = getdtablesize(); # else - fd_setsize = FD_SETSIZE; + fd_setsize = FD_SETSIZE; # endif /* !USE_SYSCONF */ #endif + } while (done == -1) { if (timeout > 0) { /* did we timeout already? */ now = gras_os_time(); DEBUG2("wakeup=%f now=%f",wakeup, now); if (now == -1 || now >= wakeup) { - /* didn't find anything */ + /* didn't find anything; no need to update _gras_lastly_selected_socket since its moredata is 0 (or we would have returned it directly) */ THROW1(timeout_error,0, "Timeout (%f) elapsed with selecting for incomming connexions", timeout); @@ -70,17 +80,24 @@ gras_socket_t gras_trp_select(double timeout) { FD_ZERO(&FDS); max_fds = -1; xbt_dynar_foreach(sockets,cursor,sock_iter) { + if (!sock_iter->valid) + continue; + if (sock_iter->incoming) { DEBUG1("Considering socket %d for select",sock_iter->sd); #ifndef HAVE_WINSOCK_H if (max_fds < sock_iter->sd) max_fds = sock_iter->sd; +#else + max_fds = 0; + #endif FD_SET(sock_iter->sd, &FDS); } else { DEBUG1("Not considering socket %d for select",sock_iter->sd); } } + if (max_fds == -1) { if (timeout > 0) { @@ -134,7 +151,7 @@ gras_socket_t gras_trp_select(double timeout) { THROW3(system_error,EINVAL,"invalid select: nb fds: %d, timeout: %d.%d", max_fds, (int)tout.tv_sec,(int) tout.tv_usec); case ENOMEM: - xbt_assert0(0,"Malloc error during the select"); + xbt_die("Malloc error during the select"); default: THROW2(system_error,errno,"Error during select: %s (%d)", strerror(errno),errno); @@ -144,7 +161,7 @@ gras_socket_t gras_trp_select(double timeout) { continue; /* this was a timeout */ } - xbt_dynar_foreach(sockets,cursor,sock_iter) { + xbt_dynar_foreach(sockets,cursor,sock_iter) { if(!FD_ISSET(sock_iter->sd, &FDS)) { /* this socket is not ready */ continue; } @@ -157,47 +174,53 @@ gras_socket_t gras_trp_select(double timeout) { /* not a socket but an ear. accept on it and serve next socket */ gras_socket_t accepted=NULL; + /* release mutex before accept; it will change the sockets dynar, so we have to break the foreach asap */ + xbt_dynar_cursor_unlock(sockets); accepted = (sock_iter->plugin->socket_accept)(sock_iter); + DEBUG2("accepted=%p,&accepted=%p",accepted,&accepted); accepted->meas = sock_iter->meas; + break; + } else { -#if 0 - FIXME: this fails of files. quite logical /* Make sure the socket is still alive by reading the first byte */ - char lookahead; int recvd; - recvd = recv(sock_iter->sd, &lookahead, 1, MSG_PEEK); + recvd = read(sock_iter->sd, &sock_iter->recvd_val, 1); if (recvd < 0) { WARN2("socket %d failed: %s", sock_iter->sd, strerror(errno)); - /* done with this socket */ - gras_socket_close(&sock_iter); - cursor--; + /* done with this socket; remove it and break the foreach since it will change the dynar */ + xbt_dynar_cursor_unlock(sockets); + gras_socket_close(sock_iter); + break; } else if (recvd == 0) { /* Connection reset (=closed) by peer. */ DEBUG1("Connection %d reset by peer", sock_iter->sd); - gras_socket_close(&sock_iter); - cursor--; + sock_iter->valid=0; /* don't close it. User may keep references to it */ } else { -#endif /* Got a suited socket ! */ XBT_OUT; + sock_iter->recvd = 1; + _gras_lastly_selected_socket = sock_iter; + /* break sync dynar iteration */ + xbt_dynar_cursor_unlock(sockets); return sock_iter; -#if 0 } -#endif } - /* if we're here, the socket we found wasn't really ready to be served */ - if (ready == 0) /* exausted all sockets given by select. Request new ones */ - break; + if (ready == 0) { /* exausted all sockets given by select. Request new ones */ + + xbt_dynar_cursor_unlock(sockets); + break; + } } } - XBT_OUT; - return NULL; + /* No socket found. Maybe we had timeout=0 and nothing to do */ + DEBUG0("TIMEOUT"); + THROW0(timeout_error,0,"Timeout"); } void gras_trp_sg_setup(gras_trp_plugin_t plug) {