--- /dev/null
+/*
+ ctdb daemon code
+
+ Copyright (C) Andrew Tridgell 2006
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+*/
+
+#include "includes.h"
+#include "db_wrap.h"
+#include "lib/tdb/include/tdb.h"
+#include "lib/events/events.h"
+#include "lib/util/dlinklist.h"
+#include "system/network.h"
+#include "system/filesys.h"
+#include "../include/ctdb.h"
+#include "../include/ctdb_private.h"
+
+#define CTDB_PATH "/tmp/ctdb.socket"
+
+
+static void ctdb_main_loop(struct ctdb_context *ctdb)
+{
+ ctdb->methods->start(ctdb);
+
+ /* go into a wait loop to allow other nodes to complete */
+ event_loop_wait(ctdb->ev);
+
+ printf("event_loop_wait() returned. this should not happen\n");
+ exit(1);
+}
+
+
+static void set_non_blocking(int fd)
+{
+ unsigned v;
+ v = fcntl(fd, F_GETFL, 0);
+ fcntl(fd, F_SETFL, v | O_NONBLOCK);
+}
+
+
+
+struct ctdb_client {
+ struct ctdb_context *ctdb;
+ struct fd_event *fde;
+ int fd;
+ struct ctdb_partial partial;
+};
+
+
+/*
+ destroy a ctdb_client
+*/
+static int ctdb_client_destructor(struct ctdb_client *client)
+{
+ close(client->fd);
+ client->fd = -1;
+ return 0;
+}
+
+
+
+static void client_request_call(struct ctdb_client *client, struct ctdb_req_call *c)
+{
+ struct ctdb_call_state *state;
+ struct ctdb_db_context *ctdb_db;
+ struct ctdb_call call;
+ struct ctdb_reply_call r;
+ int res;
+
+ for (ctdb_db=client->ctdb->db_list; ctdb_db; ctdb_db=ctdb_db->next) {
+ if (ctdb_db->db_id == c->db_id) {
+ break;
+ }
+ }
+ if (!ctdb_db) {
+ printf("Unknown database in request. db_id==0x%08x",c->db_id);
+ return;
+ }
+
+
+
+ ZERO_STRUCT(call);
+ call.call_id = c->callid;
+ call.key.dptr = c->data;
+ call.key.dsize = c->keylen;
+ call.call_data.dptr = c->data + c->keylen;
+ call.call_data.dsize = c->calldatalen;
+
+ state = ctdb_call_send(ctdb_db, &call);
+
+/* XXX this must be converted to fully async */
+ res = ctdb_call_recv(state, &call);
+ if (res != 0) {
+ printf("ctdbd_call_recv() returned error\n");
+ exit(1);
+ }
+
+ ZERO_STRUCT(r);
+#if 0
+ r.status =
+#endif
+ r.datalen = call.reply_data.dsize;
+
+ r.hdr.length = offsetof(struct ctdb_reply_call, data) + r.datalen;
+ r.hdr.ctdb_magic = c->hdr.ctdb_magic;
+ r.hdr.ctdb_version = c->hdr.ctdb_version;
+ r.hdr.operation = CTDB_REPLY_CALL;
+#if 0
+ r.hdr.destnode =
+ r.hdr.srcnode =
+#endif
+ r.hdr.reqid = c->hdr.reqid;
+
+
+/*XXX need to handle the case of partial writes logic for partial writes in tcp/ctdb_tcp_node_write */
+ res = write(client->fd, &r, offsetof(struct ctdb_reply_call, data));
+ if (r.datalen) {
+ res = write(client->fd, call.reply_data.dptr, r.datalen);
+ }
+}
+
+
+/* data contains a packet from the client */
+static void client_incoming_packet(struct ctdb_client *client, void *data, size_t nread)
+{
+ struct ctdb_req_header *hdr = data;
+
+ if (hdr->ctdb_magic != CTDB_MAGIC) {
+ ctdb_set_error(client->ctdb, "Non CTDB packet rejected\n");
+ return;
+ }
+
+ if (hdr->ctdb_version != CTDB_VERSION) {
+ ctdb_set_error(client->ctdb, "Bad CTDB version 0x%x rejected\n", hdr->ctdb_version);
+ return;
+ }
+
+ switch (hdr->operation) {
+ case CTDB_REQ_CALL:
+ client_request_call(client, (struct ctdb_req_call *)hdr);
+ break;
+
+ }
+
+ talloc_free(data);
+}
+
+
+static void ctdb_client_read(struct event_context *ev, struct fd_event *fde,
+ uint16_t flags, void *private)
+{
+ struct ctdb_client *client = talloc_get_type(private, struct ctdb_client);
+ int num_ready = 0;
+ ssize_t nread;
+ uint8_t *data, *data_base;
+
+/*XXX replace this and all other similar code (tcp) with ctdb_io.c/ctdb_read_pdu */
+ if (ioctl(client->fd, FIONREAD, &num_ready) != 0 ||
+ num_ready == 0) {
+ /* we've lost the connection from a client client. */
+ talloc_free(client);
+ return;
+ }
+
+ client->partial.data = talloc_realloc_size(client, client->partial.data,
+ num_ready + client->partial.length);
+ if (client->partial.data == NULL) {
+ /* not much we can do except drop the socket */
+ talloc_free(client);
+ return;
+ }
+
+ nread = read(client->fd, client->partial.data+client->partial.length, num_ready);
+ if (nread <= 0) {
+ /* the connection must be dead */
+ talloc_free(client);
+ return;
+ }
+
+ data = client->partial.data;
+ nread += client->partial.length;
+
+ client->partial.data = NULL;
+ client->partial.length = 0;
+
+ if (nread >= 4 && *(uint32_t *)data == nread) {
+ /* it is the responsibility of the incoming packet function to free 'data' */
+ client_incoming_packet(client, data, nread);
+ return;
+ }
+
+ data_base = data;
+
+ while (nread >= 4 && *(uint32_t *)data <= nread) {
+ /* we have at least one packet */
+ uint8_t *d2;
+ uint32_t len;
+ len = *(uint32_t *)data;
+ d2 = talloc_memdup(client, data, len);
+ if (d2 == NULL) {
+ /* sigh */
+ talloc_free(client);
+ return;
+ }
+ client_incoming_packet(client, d2, len);
+ data += len;
+ nread -= len;
+ }
+
+ if (nread > 0) {
+ /* we have only part of a packet */
+ if (data_base == data) {
+ client->partial.data = data;
+ client->partial.length = nread;
+ } else {
+ client->partial.data = talloc_memdup(client, data, nread);
+ if (client->partial.data == NULL) {
+ talloc_free(client);
+ return;
+ }
+ client->partial.length = nread;
+ talloc_free(data_base);
+ }
+ return;
+ }
+
+ talloc_free(data_base);
+}
+
+
+static void ctdb_accept_client(struct event_context *ev, struct fd_event *fde,
+ uint16_t flags, void *private)
+{
+ struct sockaddr_in addr;
+ socklen_t len;
+ int fd;
+ struct ctdb_context *ctdb = talloc_get_type(private, struct ctdb_context);
+ struct ctdb_client *client;
+
+ memset(&addr, 0, sizeof(addr));
+ len = sizeof(addr);
+ fd = accept(ctdb->daemon.sd, (struct sockaddr *)&addr, &len);
+ if (fd == -1) {
+ return;
+ }
+ set_non_blocking(fd);
+
+ client = talloc_zero(ctdb, struct ctdb_client);
+ client->ctdb = ctdb;
+ client->fd = fd;
+
+ event_add_fd(ctdb->ev, client, client->fd, EVENT_FD_READ,
+ ctdb_client_read, client);
+
+ talloc_set_destructor(client, ctdb_client_destructor);
+}
+
+
+
+static void ctdb_read_from_parent(struct event_context *ev, struct fd_event *fde,
+ uint16_t flags, void *private)
+{
+ int *fd = private;
+ int cnt;
+ char buf;
+
+ /* XXX this is a good place to try doing some cleaning up before exiting */
+ cnt = read(*fd, &buf, 1);
+ if (cnt==0) {
+ printf("parent process exited. filedescriptor dissappeared\n");
+ exit(1);
+ } else {
+ printf("ctdb: did not expect data from parent process\n");
+ exit(1);
+ }
+}
+
+
+
+/*
+ create a unix domain socket and bind it
+ return a file descriptor open on the socket
+*/
+static int ux_socket_bind(struct ctdb_context *ctdb)
+{
+ struct sockaddr_un addr;
+
+ ctdb->daemon.sd = socket(AF_UNIX, SOCK_STREAM, 0);
+ if (ctdb->daemon.sd == -1) {
+ ctdb->daemon.sd = -1;
+ return -1;
+ }
+
+ set_non_blocking(ctdb->daemon.sd);
+
+ memset(&addr, 0, sizeof(addr));
+ addr.sun_family = AF_UNIX;
+ strncpy(addr.sun_path, ctdb->daemon.name, sizeof(addr.sun_path));
+
+ if (bind(ctdb->daemon.sd, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
+ close(ctdb->daemon.sd);
+ ctdb->daemon.sd = -1;
+ return -1;
+ }
+ listen(ctdb->daemon.sd, 1);
+
+ return 0;
+}
+
+/*
+ start the protocol going
+*/
+int ctdbd_start(struct ctdb_context *ctdb)
+{
+ pid_t pid;
+ static int fd[2];
+ int res;
+ struct fd_event *fde;
+
+ /* generate a name to use for our local socket */
+ ctdb->daemon.name = talloc_asprintf(ctdb, "%s.%s", CTDB_PATH, ctdb->address.address);
+ /* get rid of any old sockets */
+ unlink(ctdb->daemon.name);
+
+ /* create a unix domain stream socket to listen to */
+ res = ux_socket_bind(ctdb);
+ if (res!=0) {
+ printf("Failed to open CTDB unix domain socket\n");
+ exit(10);
+ }
+
+ res = pipe(&fd[0]);
+ if (res) {
+ printf("Failed to open pipe for CTDB\n");
+ exit(1);
+ }
+ pid = fork();
+ if (pid==-1) {
+ printf("Failed to fork CTDB daemon\n");
+ exit(1);
+ }
+
+ if (pid) {
+ close(fd[0]);
+ close(ctdb->daemon.sd);
+ ctdb->daemon.sd = -1;
+ return 0;
+ }
+
+
+ close(fd[1]);
+ ctdb_clear_flags(ctdb, CTDB_FLAG_DAEMON_MODE);
+ ctdb->ev = event_context_init(NULL);
+ fde = event_add_fd(ctdb->ev, ctdb, fd[0], EVENT_FD_READ, ctdb_read_from_parent, &fd[0]);
+ fde = event_add_fd(ctdb->ev, ctdb, ctdb->daemon.sd, EVENT_FD_READ, ctdb_accept_client, ctdb);
+ ctdb_main_loop(ctdb);
+
+ return 0;
+}
+
+
+static void ctdb_daemon_read_cb(uint8_t *data, int cnt, void *args)
+{
+ struct ctdb_context *ctdb = talloc_get_type(args, struct ctdb_context);
+ struct ctdb_req_header *hdr;
+
+ if (cnt < sizeof(*hdr)) {
+ ctdb_set_error(ctdb, "Bad packet length %d\n", cnt);
+ return;
+ }
+ hdr = (struct ctdb_req_header *)data;
+ if (cnt != hdr->length) {
+ ctdb_set_error(ctdb, "Bad header length %d expected %d\n",
+ hdr->length, cnt);
+ return;
+ }
+
+ if (hdr->ctdb_magic != CTDB_MAGIC) {
+ ctdb_set_error(ctdb, "Non CTDB packet rejected\n");
+ return;
+ }
+
+ if (hdr->ctdb_version != CTDB_VERSION) {
+ ctdb_set_error(ctdb, "Bad CTDB version 0x%x rejected\n", hdr->ctdb_version);
+ return;
+ }
+
+ ctdb_reply_call(ctdb, hdr);
+}
+
+
+
+static void ctdb_daemon_io(struct event_context *ev, struct fd_event *fde,
+ uint16_t flags, void *private)
+{
+ struct ctdb_context *ctdb = talloc_get_type(private, struct ctdb_context);
+
+
+ if (flags&EVENT_FD_READ) {
+ ctdb_read_pdu(ctdb->daemon.sd, ctdb, &ctdb->daemon.partial, ctdb_daemon_read_cb, ctdb);
+ }
+ if (flags&EVENT_FD_WRITE) {
+ printf("socket is filled. fix this see tcp_io/ctdb_tcp_node_write how to do this\n");
+/* ctdb_daemon_write(ctdb);*/
+ }
+}
+
+/*
+ connect to a unix domain socket
+*/
+static int ux_socket_connect(struct ctdb_context *ctdb)
+{
+ struct sockaddr_un addr;
+
+ memset(&addr, 0, sizeof(addr));
+ addr.sun_family = AF_UNIX;
+ strncpy(addr.sun_path, ctdb->daemon.name, sizeof(addr.sun_path));
+
+ ctdb->daemon.sd = socket(AF_UNIX, SOCK_STREAM, 0);
+ if (ctdb->daemon.sd == -1) {
+ return -1;
+ }
+
+ if (connect(ctdb->daemon.sd, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
+ close(ctdb->daemon.sd);
+ ctdb->daemon.sd = -1;
+ return -1;
+ }
+
+ ctdb->daemon.fde = event_add_fd(ctdb->ev, ctdb, ctdb->daemon.sd, EVENT_FD_READ,
+ ctdb_daemon_io, ctdb);
+ return 0;
+}
+
+
+
+
+static int ctdb_ltdb_lock(struct ctdb_db_context *ctdb_db, TDB_DATA key)
+{
+ return tdb_chainlock(ctdb_db->ltdb->tdb, key);
+}
+
+static int ctdb_ltdb_unlock(struct ctdb_db_context *ctdb_db, TDB_DATA key)
+{
+ return tdb_chainunlock(ctdb_db->ltdb->tdb, key);
+}
+
+
+#define CTDB_DS_ALIGNMENT 8
+static void *ctdbd_allocate_pkt(struct ctdb_context *ctdb, size_t len)
+{
+ int size;
+
+ size = (len+(CTDB_DS_ALIGNMENT-1)) & ~(CTDB_DS_ALIGNMENT-1);
+ return talloc_size(ctdb, size);
+}
+
+
+struct ctdbd_queue_packet {
+ struct ctdbd_queue_packet *next, *prev;
+ uint8_t *data;
+ uint32_t length;
+};
+
+/*
+ queue a packet for sending
+*/
+int ctdbd_queue_pkt(struct ctdb_context *ctdb, struct ctdb_req_header *hdr)
+{
+ uint8_t *data = (uint8_t *)hdr;
+ uint32_t length = hdr->length;
+ struct ctdbd_queue_packet *pkt;
+ uint32_t length2;
+
+ /* enforce the length and alignment rules from the tcp packet allocator */
+ length2 = (length+(CTDB_DS_ALIGNMENT-1)) & ~(CTDB_DS_ALIGNMENT-1);
+ *(uint32_t *)data = length2;
+
+ if (length2 != length) {
+ memset(data+length, 0, length2-length);
+ }
+
+ /* if the queue is empty then try an immediate write, avoiding
+ queue overhead. This relies on non-blocking sockets */
+ if (ctdb->daemon.queue == NULL) {
+ ssize_t n = write(ctdb->daemon.sd, data, length2);
+ if (n == -1 && errno != EAGAIN && errno != EWOULDBLOCK) {
+ printf("socket to ctdb daemon has died\n");
+ return -1;
+ }
+ if (n > 0) {
+ data += n;
+ length2 -= n;
+ }
+ if (length2 == 0) return 0;
+ }
+
+ pkt = talloc(ctdb, struct ctdbd_queue_packet);
+ CTDB_NO_MEMORY(ctdb, pkt);
+
+ pkt->data = talloc_memdup(pkt, data, length2);
+ CTDB_NO_MEMORY(ctdb, pkt->data);
+
+ pkt->length = length2;
+
+ if (ctdb->daemon.queue == NULL) {
+ EVENT_FD_WRITEABLE(ctdb->daemon.fde);
+ }
+
+ DLIST_ADD_END(ctdb->daemon.queue, pkt, struct ctdbd_queue_packet *);
+
+ return 0;
+}
+
+
+/*
+ destroy a ctdb_call
+*/
+static int ctdbd_call_destructor(struct ctdb_call_state *state)
+{
+ idr_remove(state->node->ctdb->idr, state->c->hdr.reqid);
+ return 0;
+}
+
+/*
+ make a recv call to the local ctdb daemon
+
+ This is called when the program wants to wait for a ctdb_call to complete and get the
+ results. This call will block unless the call has already completed.
+*/
+int ctdbd_call_recv(struct ctdb_call_state *state, struct ctdb_call *call)
+{
+ struct ctdb_record_handle *rec;
+
+ while (state->state < CTDB_CALL_DONE) {
+ event_loop_once(state->node->ctdb->ev);
+ }
+ if (state->state != CTDB_CALL_DONE) {
+ ctdb_set_error(state->node->ctdb, "%s", state->errmsg);
+ talloc_free(state);
+ return -1;
+ }
+
+ rec = state->fetch_private;
+
+ /* ugly hack to manage forced migration */
+ if (rec != NULL) {
+ rec->data->dptr = talloc_steal(rec, state->call.reply_data.dptr);
+ rec->data->dsize = state->call.reply_data.dsize;
+ talloc_free(state);
+ return 0;
+ }
+
+ if (state->call.reply_data.dsize) {
+ call->reply_data.dptr = talloc_memdup(state->node->ctdb,
+ state->call.reply_data.dptr,
+ state->call.reply_data.dsize);
+ call->reply_data.dsize = state->call.reply_data.dsize;
+ } else {
+ call->reply_data.dptr = NULL;
+ call->reply_data.dsize = 0;
+ }
+ call->status = state->call.status;
+ talloc_free(state);
+
+ return 0;
+}
+
+/*
+ make a ctdb call to the local daemon - async send
+
+ This constructs a ctdb_call request and queues it for processing.
+ This call never blocks.
+*/
+struct ctdb_call_state *ctdbd_call_send(struct ctdb_db_context *ctdb_db, struct ctdb_call *call)
+{
+ struct ctdb_call_state *state;
+ struct ctdb_context *ctdb = ctdb_db->ctdb;
+ struct ctdb_ltdb_header header;
+ TDB_DATA data;
+ int ret;
+ size_t len;
+
+ /* if the domain socket is not yet open, open it */
+ if (ctdb->daemon.sd==-1) {
+ ux_socket_connect(ctdb);
+ }
+
+ ret = ctdb_ltdb_lock(ctdb_db, call->key);
+ if (ret != 0) {
+ printf("failed to lock ltdb record\n");
+ return NULL;
+ }
+
+ ret = ctdb_ltdb_fetch(ctdb_db, call->key, &header, ctdb_db, &data);
+ if (ret != 0) {
+ ctdb_ltdb_unlock(ctdb_db, call->key);
+ return NULL;
+ }
+
+#if 0
+ if (header.dmaster == ctdb->vnn && !(ctdb->flags & CTDB_FLAG_SELF_CONNECT)) {
+ state = ctdb_call_local_send(ctdb_db, call, &header, &data);
+ ctdb_ltdb_unlock(ctdb_db, call->key);
+ return state;
+ }
+#endif
+
+ state = talloc_zero(ctdb_db, struct ctdb_call_state);
+ if (state == NULL) {
+ printf("failed to allocate state\n");
+ ctdb_ltdb_unlock(ctdb_db, call->key);
+ return NULL;
+ }
+
+ talloc_steal(state, data.dptr);
+
+ len = offsetof(struct ctdb_req_call, data) + call->key.dsize + call->call_data.dsize;
+ state->c = ctdbd_allocate_pkt(ctdb, len);
+ if (state->c == NULL) {
+ printf("failed to allocate packet\n");
+ ctdb_ltdb_unlock(ctdb_db, call->key);
+ return NULL;
+ }
+ talloc_set_name_const(state->c, "ctdbd req_call packet");
+ talloc_steal(state, state->c);
+
+ state->c->hdr.length = len;
+ state->c->hdr.ctdb_magic = CTDB_MAGIC;
+ state->c->hdr.ctdb_version = CTDB_VERSION;
+ state->c->hdr.operation = CTDB_REQ_CALL;
+ state->c->hdr.destnode = header.dmaster;
+ state->c->hdr.srcnode = ctdb->vnn;
+ /* this limits us to 16k outstanding messages - not unreasonable */
+ state->c->hdr.reqid = idr_get_new(ctdb->idr, state, 0xFFFF);
+ state->c->flags = call->flags;
+ state->c->db_id = ctdb_db->db_id;
+ state->c->callid = call->call_id;
+ state->c->keylen = call->key.dsize;
+ state->c->calldatalen = call->call_data.dsize;
+ memcpy(&state->c->data[0], call->key.dptr, call->key.dsize);
+ memcpy(&state->c->data[call->key.dsize],
+ call->call_data.dptr, call->call_data.dsize);
+ state->call = *call;
+ state->call.call_data.dptr = &state->c->data[call->key.dsize];
+ state->call.key.dptr = &state->c->data[0];
+
+ state->node = ctdb->nodes[header.dmaster];
+ state->state = CTDB_CALL_WAIT;
+ state->header = header;
+ state->ctdb_db = ctdb_db;
+
+ talloc_set_destructor(state, ctdbd_call_destructor);
+
+ ctdbd_queue_pkt(ctdb, &state->c->hdr);
+
+/*XXX set up timeout to cleanup if server doesnt respond
+ event_add_timed(ctdb->ev, state, timeval_current_ofs(CTDB_REQ_TIMEOUT, 0),
+ ctdb_call_timeout, state);
+*/
+
+ ctdb_ltdb_unlock(ctdb_db, call->key);
+ return state;
+}
+
+
+
git.samba.org / martins / samba.git / commitdiff