/* * Release all resources */ void virCommandFree(virCommandPtr cmd) { int i; if (!cmd) return; for (i = STDERR_FILENO + 1; i < FD_SETSIZE; i++) { if (FD_ISSET(i, &cmd->transfer)) { int tmpfd = i; VIR_FORCE_CLOSE(tmpfd); } } VIR_FREE(cmd->inbuf); VIR_FORCE_CLOSE(cmd->outfd); VIR_FORCE_CLOSE(cmd->errfd); for (i = 0 ; i < cmd->nargs ; i++) VIR_FREE(cmd->args[i]); VIR_FREE(cmd->args); for (i = 0 ; i < cmd->nenv ; i++) VIR_FREE(cmd->env[i]); VIR_FREE(cmd->env); VIR_FREE(cmd->pwd); VIR_FREE(cmd->pidfile); if (cmd->reap) virCommandAbort(cmd); VIR_FREE(cmd); }
/** * qemuCreateInBridgePortWithHelper: * @cfg: the configuration object in which the helper name is looked up * @brname: the bridge name * @ifname: the returned interface name * @macaddr: the returned MAC address * @tapfd: file descriptor return value for the new tap device * @flags: OR of virNetDevTapCreateFlags: * VIR_NETDEV_TAP_CREATE_VNET_HDR * - Enable IFF_VNET_HDR on the tap device * * This function creates a new tap device on a bridge using an external * helper. The final name for the bridge will be stored in @ifname. * * Returns 0 in case of success or -1 on failure */ static int qemuCreateInBridgePortWithHelper(virQEMUDriverConfigPtr cfg, const char *brname, char **ifname, int *tapfd, unsigned int flags) { virCommandPtr cmd; char *errbuf = NULL, *cmdstr = NULL; int pair[2] = { -1, -1 }; if ((flags & ~VIR_NETDEV_TAP_CREATE_VNET_HDR) != VIR_NETDEV_TAP_CREATE_IFUP) return -1; if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) < 0) { virReportSystemError(errno, "%s", _("failed to create socket")); return -1; } if (!virFileIsExecutable(cfg->bridgeHelperName)) { virReportSystemError(errno, _("'%s' is not a suitable bridge helper"), cfg->bridgeHelperName); return -1; } cmd = virCommandNew(cfg->bridgeHelperName); if (flags & VIR_NETDEV_TAP_CREATE_VNET_HDR) virCommandAddArgFormat(cmd, "--use-vnet"); virCommandAddArgFormat(cmd, "--br=%s", brname); virCommandAddArgFormat(cmd, "--fd=%d", pair[1]); virCommandSetErrorBuffer(cmd, &errbuf); virCommandDoAsyncIO(cmd); virCommandPassFD(cmd, pair[1], VIR_COMMAND_PASS_FD_CLOSE_PARENT); virCommandClearCaps(cmd); #ifdef CAP_NET_ADMIN virCommandAllowCap(cmd, CAP_NET_ADMIN); #endif if (virCommandRunAsync(cmd, NULL) < 0) { *tapfd = -1; goto cleanup; } do { *tapfd = recvfd(pair[0], 0); } while (*tapfd < 0 && errno == EINTR); if (*tapfd < 0) { char ebuf[1024]; char *errstr = NULL; if (!(cmdstr = virCommandToString(cmd))) goto cleanup; virCommandAbort(cmd); if (errbuf && *errbuf && virAsprintf(&errstr, "\nstderr=%s", errbuf) < 0) goto cleanup; virReportError(VIR_ERR_INTERNAL_ERROR, _("%s: failed to communicate with bridge helper: %s%s"), cmdstr, virStrerror(errno, ebuf, sizeof(ebuf)), errstr ? errstr : ""); VIR_FREE(errstr); goto cleanup; } if (virNetDevTapGetName(*tapfd, ifname) < 0 || virCommandWait(cmd, NULL) < 0) { VIR_FORCE_CLOSE(*tapfd); *tapfd = -1; } cleanup: VIR_FREE(cmdstr); VIR_FREE(errbuf); virCommandFree(cmd); VIR_FORCE_CLOSE(pair[0]); return *tapfd < 0 ? -1 : 0; }