lca2011: oserver_restore to restore fields we labelled CDUMP_IGNORE.

[ccan-lca-2011.git] / ccan / oserver / oserver.c

diff --git a/ccan/oserver/oserver.c b/ccan/oserver/oserver.c
index 0ec1b6840ee40ea1ae548e9e300590e44f7d1f3d..50b49bd5f94746c8259fb3c609c285c5d68684c9 100644 (file)
--- a/ccan/oserver/oserver.c
+++ b/ccan/oserver/oserver.c
@@ -1,9 +1,11 @@
 #include <ccan/oserver/oserver.h>
 #include <ccan/oserver/oserver_types.h>
+#include <ccan/oserver/oserver_cdump.h>
 #include <ccan/read_write_all/read_write_all.h>
 #include <ccan/opt/opt.h>
 #include <ccan/tevent/tevent.h>
 #include <ccan/array_size/array_size.h>
+#include <ccan/grab_file/grab_file.h>
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <netinet/in.h>
@@ -17,6 +19,9 @@
 #include <errno.h>
 #include <signal.h>
 #include <assert.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
 
 static uint16_t state_flag_map[] = {
        [SENDING_GREETING]              = TEVENT_FD_WRITE,
@@ -284,7 +289,96 @@ static void talloc_dump(struct tevent_context *ev,
        }
 }
 
-struct oserver *oserver_setup(struct tevent_context *ev, unsigned short port)
+static void dump(struct tevent_context *ev,
+                struct tevent_signal *se,
+                int signum,
+                int count,
+                void *siginfo,
+                void *_oserver)
+{
+       struct oserver *oserver = _oserver;
+       char *str;
+       int fd;
+
+       str = cdump_bundle(ev, cdump_struct_oserver, oserver);
+       fd = open(oserver->dumpfile, O_CREAT|O_TRUNC|O_WRONLY, 0600);
+       write(fd, str, strlen(str));
+       close(fd);
+       talloc_free(str);
+}
+
+static bool load_file(struct oserver *oserver, const char *file)
+{
+       char *str;
+
+       if (!file)
+               return false;
+
+       str = grab_file(oserver, file, NULL);
+       if (!str)
+               return false;
+
+       if (!cdump_unbundle(oserver, cdump_struct_oserver, oserver, str)) {
+               talloc_free(str);
+               return false;
+       }
+       talloc_free(str);
+       return true;
+}
+
+static bool complete_server(struct tevent_context *ev,
+                           struct oserver *oserver, const char *dumpfile)
+{
+       /* Re-set this even if restored from file, in case it changed. */
+       oserver->dumpfile = dumpfile;
+       if (oserver->dumpfile)
+               tevent_add_signal(ev, oserver, SIGHUP, SA_RESTART,
+                                 dump, oserver);
+
+       /* Don't kill us if client dies. */
+       signal(SIGPIPE, SIG_IGN);
+
+       /* Show talloc tree on SIGUSR1. */
+       tevent_add_signal(ev, oserver, SIGUSR1, SA_RESTART,
+                         talloc_dump, oserver);
+
+       oserver->fde = tevent_add_fd(ev, oserver, oserver->fd,
+                                    TEVENT_FD_READ, add_client, oserver);
+       if (!oserver->fde)
+               return false;
+       return true;
+}
+
+struct oserver *oserver_restore(struct tevent_context *ev, const char *dumpfile)
+{
+       unsigned int i;
+       struct oserver *oserver = talloc(ev, struct oserver);
+       if (!load_file(oserver, dumpfile)) {
+               talloc_free(oserver);
+               return NULL;
+       }
+
+       /* Restore ignored fields in clients (fde and oserver). */
+       for (i = 0; i < ARRAY_SIZE(oserver->clients); i++) {
+               struct client *client = oserver->clients[i];
+               if (!client)
+                       continue;
+               client->oserver = oserver;
+               client->fde = tevent_add_fd(ev, client, client->fd,
+                                           state_flag_map[client->state],
+                                           service_client, client);
+               tevent_fd_set_auto_close(client->fde);
+       }
+
+       if (!complete_server(ev, oserver, dumpfile)) {
+               talloc_free(oserver);
+               return NULL;
+       }
+       return oserver;
+}
+
+struct oserver *oserver_setup(struct tevent_context *ev, unsigned short port,
+                             const char *dumpfile)
 {
        struct oserver *oserver;
        int one = 1;
@@ -320,19 +414,10 @@ struct oserver *oserver_setup(struct tevent_context *ev, unsigned short port)
                return NULL;
        }
 
-       oserver->fde = tevent_add_fd(ev, oserver, oserver->fd,
-                                    TEVENT_FD_READ, add_client, oserver);
-       if (!oserver->fde) {
+       if (!complete_server(ev, oserver, dumpfile)) {
                talloc_free(oserver);
                return NULL;
        }
 
-       /* Don't kill us if client dies. */
-       signal(SIGPIPE, SIG_IGN);
-
-       /* Show talloc tree on SIGUSR1. */
-       tevent_add_signal(ev, oserver, SIGUSR1, SA_RESTART,
-                         talloc_dump, oserver);
-
        return oserver;
 }