locking: Add a standalone helper to lock record/db

Signed-off-by: Amitay Isaacs <amitay@gmail.com>

diff --git a/Makefile.in b/Makefile.in
index 9f94aee79295587ee8b92a6fa4b192c3c3ade003..71c3f3186e4bf6f073547b80553dec8d79b719d1 100755 (executable)
--- a/Makefile.in
+++ b/Makefile.in
@@ -107,7 +107,8 @@ TEST_BINS=tests/bin/ctdb_bench tests/bin/ctdb_fetch tests/bin/ctdb_fetch_one \
        tests/bin/ctdb_porting_tests \
        @INFINIBAND_BINS@
 
-BINS = bin/ctdb @CTDB_SCSI_IO@ bin/smnotify bin/ping_pong bin/ltdbtool @CTDB_PMDA@
+BINS = bin/ctdb @CTDB_SCSI_IO@ bin/smnotify bin/ping_pong bin/ltdbtool \
+       bin/ctdb_lock_helper @CTDB_PMDA@
 
 SBINS = bin/ctdbd
 
@@ -176,6 +177,10 @@ bin/ltdbtool: tools/ltdbtool.o $(TDB_OBJ)
        @echo Linking $@
        @$(CC) $(CFLAGS) -o $@ $+ $(TDB_LIBS) $(LIB_FLAGS)
 
+bin/ctdb_lock_helper: server/ctdb_lock_helper.o lib/util/util_file.o $(TALLOC_OBJ) $(TDB_OBJ)
+       @echo Linking $@
+       @$(CC) $(CFLAGS) -o $@ $+ $(TDB_LIBS) $(LIB_FLAGS)
+
 bin/smnotify: utils/smnotify/gen_xdr.o utils/smnotify/gen_smnotify.o utils/smnotify/smnotify.o $(POPT_OBJ)
        @echo Linking $@
        @$(CC) $(CFLAGS) -o $@ utils/smnotify/smnotify.o utils/smnotify/gen_xdr.o utils/smnotify/gen_smnotify.o $(POPT_OBJ) $(LIB_FLAGS)
@@ -327,6 +332,7 @@ install: all manpages $(PMDA_INSTALL)
        ${INSTALLCMD} -m 755 bin/smnotify $(DESTDIR)$(bindir)
        $(INSTALLCMD) -m 755 bin/ping_pong $(DESTDIR)$(bindir)
        $(INSTALLCMD) -m 755 bin/ltdbtool $(DESTDIR)$(bindir)
+       $(INSTALLCMD) -m 755 bin/ctdb_lock_helper $(DESTDIR)$(bindir)
        $(INSTALLCMD) -m 755 libctdb/libctdb.a $(DESTDIR)$(libdir)
        ${INSTALLCMD} -m 644 include/ctdb.h $(DESTDIR)$(includedir)
        ${INSTALLCMD} -m 644 include/ctdb_client.h $(DESTDIR)$(includedir)

diff --git a/packaging/RPM/ctdb.spec.in b/packaging/RPM/ctdb.spec.in
index 910b59acd3006d24684c27999ebe5e0be609ffc7..98724279472ba80892dc16a15bbe402709c2ed40 100644 (file)
--- a/packaging/RPM/ctdb.spec.in
+++ b/packaging/RPM/ctdb.spec.in
@@ -166,6 +166,7 @@ rm -rf $RPM_BUILD_ROOT
 %{_sysconfdir}/ctdb/notify.d/README
 %{_sbindir}/ctdbd
 %{_bindir}/ctdb
+%{_bindir}/ctdb_lock_helper
 %{_bindir}/smnotify
 %{_bindir}/ping_pong
 %{_bindir}/ltdbtool

diff --git a/server/ctdb_lock_helper.c b/server/ctdb_lock_helper.c
new file mode 100644 (file)
index 0000000..d8a1d24
--- /dev/null
+++ b/server/ctdb_lock_helper.c
@@ -0,0 +1,148 @@
+/*
+   ctdb lock helper
+
+   Copyright (C) Amitay Isaacs  2013
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program 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 General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "includes.h"
+#include "tdb.h"
+#include "system/filesys.h"
+#include "../include/ctdb_private.h"
+
+static char *progname = NULL;
+
+static void send_result(int fd, char result)
+{
+       write(fd, &result, 1);
+       if (result == 1) {
+               exit(1);
+       }
+}
+
+
+static void usage(void)
+{
+       fprintf(stderr, "\n");
+       fprintf(stderr, "Usage: %s <ctdbd-pid> <output-fd> RECORD <db-path> <db-key>\n",
+               progname);
+       fprintf(stderr, "       %s <ctdbd-pid> <output-fd> DB <db1-path> [<db2-path> ...]\n",
+               progname);
+}
+
+
+static int lock_record(const char *dbpath, const char *dbkey)
+{
+       TDB_DATA key;
+       struct tdb_context *tdb;
+
+       /* Convert hex key to key */
+       if (strcmp(dbkey, "NULL") == 0) {
+               key.dptr = NULL;
+               key.dsize = 0;
+       } else {
+               key.dptr = hex_decode_talloc(NULL, dbkey, &key.dsize);
+       }
+
+       tdb = tdb_open(dbpath, 0, TDB_DEFAULT, O_RDWR, 0600);
+       if (tdb == NULL) {
+               fprintf(stderr, "%s: Error opening database %s\n", progname, dbpath);
+               return 1;
+       }
+
+       if (tdb_chainlock(tdb, key) < 0) {
+               fprintf(stderr, "%s: Error getting record lock (%s)\n",
+                       progname, tdb_errorstr(tdb));
+               return 1;
+       }
+
+       return 0;
+
+}
+
+
+static int lock_db(const char *dbpath)
+{
+       struct tdb_context *tdb;
+
+       tdb = tdb_open(dbpath, 0, TDB_DEFAULT, O_RDWR, 0600);
+       if (tdb == NULL) {
+               fprintf(stderr, "%s: Error opening database %s\n", progname, dbpath);
+               return 1;
+       }
+
+       if (tdb_lockall(tdb) < 0) {
+               fprintf(stderr, "%s: Error getting db lock (%s)\n",
+                       progname, tdb_errorstr(tdb));
+               return 1;
+       }
+
+       return 0;
+}
+
+
+int main(int argc, char *argv[])
+{
+       int write_fd;
+       char result = 0;
+       int ppid;
+       const char *lock_type;
+
+       progname = argv[0];
+
+       if (argc < 4) {
+               usage();
+               exit(1);
+       }
+
+       ppid = atoi(argv[1]);
+       write_fd = atoi(argv[2]);
+       lock_type = argv[3];
+
+       if (strcmp(lock_type, "RECORD") == 0) {
+               if (argc != 6) {
+                       fprintf(stderr, "%s: Invalid number of arguments (%d)\n",
+                               progname, argc);
+                       usage();
+                       exit(1);
+               }
+               result = lock_record(argv[4], argv[5]);
+
+       } else if (strcmp(lock_type, "DB") == 0) {
+               int n;
+
+               /* If there are no databases specified, no need for lock */
+               if (argc > 4) {
+                       for (n=4; n<argc; n++) {
+                               result = lock_db(argv[n]);
+                               if (result != 0) {
+                                       break;
+                               }
+                       }
+               }
+
+       } else {
+               fprintf(stderr, "%s: Invalid lock-type '%s'\n", progname, lock_type);
+               usage();
+               exit(1);
+       }
+
+       send_result(write_fd, result);
+
+       while (kill(ppid, 0) == 0 || errno != ESRCH) {
+               sleep(5);
+       }
+       return 0;
+}