summaryrefslogtreecommitdiff
path: root/source3/lib
diff options
context:
space:
mode:
authorVolker Lendecke <vlendec@samba.org>2007-05-24 14:47:24 +0000
committerGerald (Jerry) Carter <jerry@samba.org>2007-10-10 12:22:47 -0500
commitf260b45d646ae69602f63c1f6a002384b4828a1c (patch)
tree29153c9ce8d72fe6c3945abfc096bfa553ab0540 /source3/lib
parent509d90f1cc21ab528433d633b8d074e5e7c30949 (diff)
downloadsamba-f260b45d646ae69602f63c1f6a002384b4828a1c.tar.gz
samba-f260b45d646ae69602f63c1f6a002384b4828a1c.tar.bz2
samba-f260b45d646ae69602f63c1f6a002384b4828a1c.zip
r23117: Factor out local messaging.
This removes message_block / message_unblock. I've talked to Jeremy and Günther, giving them my reasons why I believe they have no effect. Neither could come up with a counter-argument, so they go :-) (This used to be commit a925e0991ffbaea4a533bab3a5d61e5d367d46c8)
Diffstat (limited to 'source3/lib')
-rw-r--r--source3/lib/messages.c425
-rw-r--r--source3/lib/messages_local.c431
2 files changed, 457 insertions, 399 deletions
diff --git a/source3/lib/messages.c b/source3/lib/messages.c
index e1434ff01f..056286f89a 100644
--- a/source3/lib/messages.c
+++ b/source3/lib/messages.c
@@ -50,12 +50,6 @@
#include "librpc/gen_ndr/messaging.h"
#include "librpc/gen_ndr/ndr_messaging.h"
-/* the locking database handle */
-static int received_signal;
-
-/* change the message version with any incompatible changes in the protocol */
-#define MESSAGE_VERSION 2
-
struct messaging_callback {
struct messaging_callback *prev, *next;
uint32 msg_type;
@@ -65,25 +59,6 @@ struct messaging_callback {
void *private_data;
};
-struct messaging_context {
- TDB_CONTEXT *tdb;
- struct server_id id;
- struct event_context *event_ctx;
- struct messaging_callback *callbacks;
-
-
-};
-
-/****************************************************************************
- Notifications come in as signals.
-****************************************************************************/
-
-static void sig_usr1(void)
-{
- received_signal = 1;
- sys_select_signal(SIGUSR1);
-}
-
/****************************************************************************
A useful function for testing the message system.
****************************************************************************/
@@ -102,362 +77,6 @@ static void ping_message(struct messaging_context *msg_ctx,
}
/****************************************************************************
- Initialise the messaging functions.
-****************************************************************************/
-
-static BOOL message_tdb_init(struct messaging_context *msg_ctx)
-{
- sec_init();
-
- msg_ctx->tdb = tdb_open_log(lock_path("messages.tdb"),
- 0, TDB_CLEAR_IF_FIRST|TDB_DEFAULT,
- O_RDWR|O_CREAT,0600);
-
- if (!msg_ctx->tdb) {
- DEBUG(0,("ERROR: Failed to initialise messages database\n"));
- return False;
- }
-
- /* Activate the per-hashchain freelist */
- tdb_set_max_dead(msg_ctx->tdb, 5);
-
- CatchSignal(SIGUSR1, SIGNAL_CAST sig_usr1);
-
- return True;
-}
-
-/*******************************************************************
- Form a static tdb key from a pid.
-******************************************************************/
-
-static TDB_DATA message_key_pid(struct server_id pid)
-{
- static char key[20];
- TDB_DATA kbuf;
-
- slprintf(key, sizeof(key)-1, "PID/%s", procid_str_static(&pid));
-
- kbuf.dptr = (uint8 *)key;
- kbuf.dsize = strlen(key)+1;
- return kbuf;
-}
-
-/*
- Fetch the messaging array for a process
- */
-
-static NTSTATUS messaging_tdb_fetch(TDB_CONTEXT *msg_tdb,
- TDB_DATA key,
- TALLOC_CTX *mem_ctx,
- struct messaging_array **presult)
-{
- struct messaging_array *result;
- TDB_DATA data;
- DATA_BLOB blob;
- NTSTATUS status;
-
- if (!(result = TALLOC_ZERO_P(mem_ctx, struct messaging_array))) {
- return NT_STATUS_NO_MEMORY;
- }
-
- data = tdb_fetch(msg_tdb, key);
-
- if (data.dptr == NULL) {
- *presult = result;
- return NT_STATUS_OK;
- }
-
- blob = data_blob_const(data.dptr, data.dsize);
-
- status = ndr_pull_struct_blob(
- &blob, result, result,
- (ndr_pull_flags_fn_t)ndr_pull_messaging_array);
-
- SAFE_FREE(data.dptr);
-
- if (!NT_STATUS_IS_OK(status)) {
- TALLOC_FREE(result);
- return status;
- }
-
- if (DEBUGLEVEL >= 10) {
- DEBUG(10, ("messaging_tdb_fetch:\n"));
- NDR_PRINT_DEBUG(messaging_array, result);
- }
-
- *presult = result;
- return NT_STATUS_OK;
-}
-
-/*
- Store a messaging array for a pid
-*/
-
-static NTSTATUS messaging_tdb_store(TDB_CONTEXT *msg_tdb,
- TDB_DATA key,
- struct messaging_array *array)
-{
- TDB_DATA data;
- DATA_BLOB blob;
- NTSTATUS status;
- TALLOC_CTX *mem_ctx;
- int ret;
-
- if (array->num_messages == 0) {
- tdb_delete(msg_tdb, key);
- return NT_STATUS_OK;
- }
-
- if (!(mem_ctx = talloc_new(array))) {
- return NT_STATUS_NO_MEMORY;
- }
-
- status = ndr_push_struct_blob(
- &blob, mem_ctx, array,
- (ndr_push_flags_fn_t)ndr_push_messaging_array);
-
- if (!NT_STATUS_IS_OK(status)) {
- talloc_free(mem_ctx);
- return status;
- }
-
- if (DEBUGLEVEL >= 10) {
- DEBUG(10, ("messaging_tdb_store:\n"));
- NDR_PRINT_DEBUG(messaging_array, array);
- }
-
- data.dptr = blob.data;
- data.dsize = blob.length;
-
- ret = tdb_store(msg_tdb, key, data, TDB_REPLACE);
- TALLOC_FREE(mem_ctx);
-
- return (ret == 0) ? NT_STATUS_OK : NT_STATUS_INTERNAL_DB_CORRUPTION;
-}
-
-/****************************************************************************
- Notify a process that it has a message. If the process doesn't exist
- then delete its record in the database.
-****************************************************************************/
-
-static NTSTATUS message_notify(struct server_id procid)
-{
- pid_t pid = procid.pid;
- int ret;
- uid_t euid = geteuid();
-
- /*
- * Doing kill with a non-positive pid causes messages to be
- * sent to places we don't want.
- */
-
- SMB_ASSERT(pid > 0);
-
- if (euid != 0) {
- /* If we're not root become so to send the message. */
- save_re_uid();
- set_effective_uid(0);
- }
-
- ret = kill(pid, SIGUSR1);
-
- if (euid != 0) {
- /* Go back to who we were. */
- int saved_errno = errno;
- restore_re_uid_fromroot();
- errno = saved_errno;
- }
-
- if (ret == 0) {
- return NT_STATUS_OK;
- }
-
- /*
- * Something has gone wrong
- */
-
- DEBUG(2,("message to process %d failed - %s\n", (int)pid,
- strerror(errno)));
-
- /*
- * No call to map_nt_error_from_unix -- don't want to link in
- * errormap.o into lots of utils.
- */
-
- if (errno == ESRCH) return NT_STATUS_INVALID_HANDLE;
- if (errno == EINVAL) return NT_STATUS_INVALID_PARAMETER;
- if (errno == EPERM) return NT_STATUS_ACCESS_DENIED;
- return NT_STATUS_UNSUCCESSFUL;
-}
-
-/****************************************************************************
- Send a message to a particular pid.
-****************************************************************************/
-
-static NTSTATUS messaging_tdb_send(struct messaging_context *msg_ctx,
- struct server_id pid, int msg_type,
- const DATA_BLOB *data)
-{
- struct messaging_array *msg_array;
- struct messaging_rec *rec;
- TALLOC_CTX *mem_ctx;
- NTSTATUS status;
- TDB_DATA key = message_key_pid(pid);
-
- /* NULL pointer means implicit length zero. */
- if (!data->data) {
- SMB_ASSERT(data->length == 0);
- }
-
- /*
- * Doing kill with a non-positive pid causes messages to be
- * sent to places we don't want.
- */
-
- SMB_ASSERT(procid_to_pid(&pid) > 0);
-
- if (!(mem_ctx = talloc_init("message_send_pid"))) {
- return NT_STATUS_NO_MEMORY;
- }
-
- if (tdb_chainlock(msg_ctx->tdb, key) == -1) {
- TALLOC_FREE(mem_ctx);
- return NT_STATUS_LOCK_NOT_GRANTED;
- }
-
- status = messaging_tdb_fetch(msg_ctx->tdb, key, mem_ctx, &msg_array);
-
- if (!NT_STATUS_IS_OK(status)) {
- goto done;
- }
-
- if ((msg_type & MSG_FLAG_LOWPRIORITY)
- && (msg_array->num_messages > 1000)) {
- DEBUG(5, ("Dropping message for PID %s\n",
- procid_str_static(&pid)));
- status = NT_STATUS_INSUFFICIENT_RESOURCES;
- goto done;
- }
-
- if (!(rec = TALLOC_REALLOC_ARRAY(mem_ctx, msg_array->messages,
- struct messaging_rec,
- msg_array->num_messages+1))) {
- status = NT_STATUS_NO_MEMORY;
- goto done;
- }
-
- rec[msg_array->num_messages].msg_version = MESSAGE_VERSION;
- rec[msg_array->num_messages].msg_type = msg_type & MSG_TYPE_MASK;
- rec[msg_array->num_messages].dest = pid;
- rec[msg_array->num_messages].src = procid_self();
- rec[msg_array->num_messages].buf = *data;
-
- msg_array->messages = rec;
- msg_array->num_messages += 1;
-
- status = messaging_tdb_store(msg_ctx->tdb, key, msg_array);
-
- if (!NT_STATUS_IS_OK(status)) {
- goto done;
- }
-
- status = message_notify(pid);
-
- if (NT_STATUS_EQUAL(status, NT_STATUS_INVALID_HANDLE)) {
- DEBUG(2, ("pid %s doesn't exist - deleting messages record\n",
- procid_str_static(&pid)));
- tdb_delete(msg_ctx->tdb, message_key_pid(pid));
- }
-
- done:
- tdb_chainunlock(msg_ctx->tdb, key);
- TALLOC_FREE(mem_ctx);
- return status;
-}
-
-/****************************************************************************
- Retrieve all messages for the current process.
-****************************************************************************/
-
-static NTSTATUS retrieve_all_messages(TDB_CONTEXT *msg_tdb,
- TALLOC_CTX *mem_ctx,
- struct messaging_array **presult)
-{
- struct messaging_array *result;
- TDB_DATA key = message_key_pid(procid_self());
- NTSTATUS status;
-
- if (tdb_chainlock(msg_tdb, key) == -1) {
- return NT_STATUS_LOCK_NOT_GRANTED;
- }
-
- status = messaging_tdb_fetch(msg_tdb, key, mem_ctx, &result);
-
- /*
- * We delete the record here, tdb_set_max_dead keeps it around
- */
- tdb_delete(msg_tdb, key);
- tdb_chainunlock(msg_tdb, key);
-
- if (NT_STATUS_IS_OK(status)) {
- *presult = result;
- }
-
- return status;
-}
-
-/*
- Dispatch one messsaging_rec
-*/
-static void messaging_dispatch_rec(struct messaging_context *msg_ctx,
- struct messaging_rec *rec)
-{
- struct messaging_callback *cb, *next;
-
- for (cb = msg_ctx->callbacks; cb != NULL; cb = next) {
- next = cb->next;
- if (cb->msg_type == rec->msg_type) {
- cb->fn(msg_ctx, cb->private_data, rec->msg_type,
- rec->src, &rec->buf);
- return;
- }
- }
- return;
-}
-
-/****************************************************************************
- Receive and dispatch any messages pending for this process.
- JRA changed Dec 13 2006. Only one message handler now permitted per type.
- *NOTE*: Dispatch functions must be able to cope with incoming
- messages on an *odd* byte boundary.
-****************************************************************************/
-
-void message_dispatch(struct messaging_context *msg_ctx)
-{
- struct messaging_array *msg_array = NULL;
- uint32 i;
-
- if (!received_signal)
- return;
-
- DEBUG(10, ("message_dispatch: received_signal = %d\n",
- received_signal));
-
- received_signal = 0;
-
- if (!NT_STATUS_IS_OK(retrieve_all_messages(msg_ctx->tdb, NULL,
- &msg_array))) {
- return;
- }
-
- for (i=0; i<msg_array->num_messages; i++) {
- messaging_dispatch_rec(msg_ctx, &msg_array->messages[i]);
- }
-
- TALLOC_FREE(msg_array);
-}
-
-/****************************************************************************
Register/replace a dispatch function for a particular message type.
JRA changed Dec 13 2006. Only one message handler now permitted per type.
*NOTE*: Dispatch functions must be able to cope with incoming
@@ -564,21 +183,6 @@ BOOL message_send_all(struct messaging_context *msg_ctx,
return True;
}
-/*
- * Block and unblock receiving of messages. Allows removal of race conditions
- * when doing a fork and changing message disposition.
- */
-
-void message_block(void)
-{
- BlockSignals(True, SIGUSR1);
-}
-
-void message_unblock(void)
-{
- BlockSignals(False, SIGUSR1);
-}
-
struct event_context *messaging_event_context(struct messaging_context *msg_ctx)
{
return msg_ctx->event_ctx;
@@ -589,6 +193,7 @@ struct messaging_context *messaging_init(TALLOC_CTX *mem_ctx,
struct event_context *ev)
{
struct messaging_context *ctx;
+ NTSTATUS status;
if (!(ctx = TALLOC_ZERO_P(mem_ctx, struct messaging_context))) {
return NULL;
@@ -597,8 +202,10 @@ struct messaging_context *messaging_init(TALLOC_CTX *mem_ctx,
ctx->id = server_id;
ctx->event_ctx = ev;
- if (!message_tdb_init(ctx)) {
- DEBUG(0, ("message_init failed: %s\n", strerror(errno)));
+ status = messaging_tdb_init(ctx, ctx, &ctx->local);
+
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(0, ("message_init failed: %s\n", nt_errstr(status)));
TALLOC_FREE(ctx);
}
@@ -677,7 +284,8 @@ NTSTATUS messaging_send(struct messaging_context *msg_ctx,
struct server_id server, uint32_t msg_type,
const DATA_BLOB *data)
{
- return messaging_tdb_send(msg_ctx, server, msg_type, data);
+ return msg_ctx->local->send_fn(msg_ctx, server, msg_type, data,
+ msg_ctx->local);
}
NTSTATUS messaging_send_buf(struct messaging_context *msg_ctx,
@@ -688,4 +296,23 @@ NTSTATUS messaging_send_buf(struct messaging_context *msg_ctx,
return messaging_send(msg_ctx, server, msg_type, &blob);
}
+/*
+ Dispatch one messsaging_rec
+*/
+void messaging_dispatch_rec(struct messaging_context *msg_ctx,
+ struct messaging_rec *rec)
+{
+ struct messaging_callback *cb, *next;
+
+ for (cb = msg_ctx->callbacks; cb != NULL; cb = next) {
+ next = cb->next;
+ if (cb->msg_type == rec->msg_type) {
+ cb->fn(msg_ctx, cb->private_data, rec->msg_type,
+ rec->src, &rec->buf);
+ return;
+ }
+ }
+ return;
+}
+
/** @} **/
diff --git a/source3/lib/messages_local.c b/source3/lib/messages_local.c
new file mode 100644
index 0000000000..b459ce0238
--- /dev/null
+++ b/source3/lib/messages_local.c
@@ -0,0 +1,431 @@
+/*
+ Unix SMB/CIFS implementation.
+ Samba internal messaging functions
+ Copyright (C) 2007 by Volker Lendecke
+
+ 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 2 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, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+/**
+ @defgroup messages Internal messaging framework
+ @{
+ @file messages.c
+
+ @brief Module for internal messaging between Samba daemons.
+
+ The idea is that if a part of Samba wants to do communication with
+ another Samba process then it will do a message_register() of a
+ dispatch function, and use message_send_pid() to send messages to
+ that process.
+
+ The dispatch function is given the pid of the sender, and it can
+ use that to reply by message_send_pid(). See ping_message() for a
+ simple example.
+
+ @caution Dispatch functions must be able to cope with incoming
+ messages on an *odd* byte boundary.
+
+ This system doesn't have any inherent size limitations but is not
+ very efficient for large messages or when messages are sent in very
+ quick succession.
+
+*/
+
+#include "includes.h"
+#include "librpc/gen_ndr/messaging.h"
+#include "librpc/gen_ndr/ndr_messaging.h"
+
+/* the locking database handle */
+static int received_signal;
+
+static NTSTATUS messaging_tdb_send(struct messaging_context *msg_ctx,
+ struct server_id pid, int msg_type,
+ const DATA_BLOB *data,
+ struct messaging_backend *backend);
+
+/****************************************************************************
+ Notifications come in as signals.
+****************************************************************************/
+
+static void sig_usr1(void)
+{
+ received_signal = 1;
+ sys_select_signal(SIGUSR1);
+}
+
+static int messaging_tdb_destructor(struct messaging_backend *tdb_ctx)
+{
+ TDB_CONTEXT *tdb = (TDB_CONTEXT *)tdb_ctx->private_data;
+ tdb_close(tdb);
+ return 0;
+}
+
+/****************************************************************************
+ Initialise the messaging functions.
+****************************************************************************/
+
+NTSTATUS messaging_tdb_init(struct messaging_context *msg_ctx,
+ TALLOC_CTX *mem_ctx,
+ struct messaging_backend **presult)
+{
+ struct messaging_backend *result;
+ TDB_CONTEXT *tdb;
+
+ if (!(result = TALLOC_P(mem_ctx, struct messaging_backend))) {
+ DEBUG(0, ("talloc failed\n"));
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ tdb = tdb_open_log(lock_path("messages.tdb"),
+ 0, TDB_CLEAR_IF_FIRST|TDB_DEFAULT,
+ O_RDWR|O_CREAT,0600);
+
+ if (!tdb) {
+ DEBUG(0,("ERROR: Failed to initialise messages database\n"));
+ TALLOC_FREE(result);
+ return NT_STATUS_INTERNAL_DB_CORRUPTION;
+ }
+
+ sec_init();
+
+ /* Activate the per-hashchain freelist */
+ tdb_set_max_dead(tdb, 5);
+
+ CatchSignal(SIGUSR1, SIGNAL_CAST sig_usr1);
+
+ result->private_data = (void *)tdb;
+ result->send_fn = messaging_tdb_send;
+
+ talloc_set_destructor(result, messaging_tdb_destructor);
+
+ *presult = result;
+ return NT_STATUS_OK;
+}
+
+/*******************************************************************
+ Form a static tdb key from a pid.
+******************************************************************/
+
+static TDB_DATA message_key_pid(struct server_id pid)
+{
+ static char key[20];
+ TDB_DATA kbuf;
+
+ slprintf(key, sizeof(key)-1, "PID/%s", procid_str_static(&pid));
+
+ kbuf.dptr = (uint8 *)key;
+ kbuf.dsize = strlen(key)+1;
+ return kbuf;
+}
+
+/*
+ Fetch the messaging array for a process
+ */
+
+static NTSTATUS messaging_tdb_fetch(TDB_CONTEXT *msg_tdb,
+ TDB_DATA key,
+ TALLOC_CTX *mem_ctx,
+ struct messaging_array **presult)
+{
+ struct messaging_array *result;
+ TDB_DATA data;
+ DATA_BLOB blob;
+ NTSTATUS status;
+
+ if (!(result = TALLOC_ZERO_P(mem_ctx, struct messaging_array))) {
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ data = tdb_fetch(msg_tdb, key);
+
+ if (data.dptr == NULL) {
+ *presult = result;
+ return NT_STATUS_OK;
+ }
+
+ blob = data_blob_const(data.dptr, data.dsize);
+
+ status = ndr_pull_struct_blob(
+ &blob, result, result,
+ (ndr_pull_flags_fn_t)ndr_pull_messaging_array);
+
+ SAFE_FREE(data.dptr);
+
+ if (!NT_STATUS_IS_OK(status)) {
+ TALLOC_FREE(result);
+ return status;
+ }
+
+ if (DEBUGLEVEL >= 10) {
+ DEBUG(10, ("messaging_tdb_fetch:\n"));
+ NDR_PRINT_DEBUG(messaging_array, result);
+ }
+
+ *presult = result;
+ return NT_STATUS_OK;
+}
+
+/*
+ Store a messaging array for a pid
+*/
+
+static NTSTATUS messaging_tdb_store(TDB_CONTEXT *msg_tdb,
+ TDB_DATA key,
+ struct messaging_array *array)
+{
+ TDB_DATA data;
+ DATA_BLOB blob;
+ NTSTATUS status;
+ TALLOC_CTX *mem_ctx;
+ int ret;
+
+ if (array->num_messages == 0) {
+ tdb_delete(msg_tdb, key);
+ return NT_STATUS_OK;
+ }
+
+ if (!(mem_ctx = talloc_new(array))) {
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ status = ndr_push_struct_blob(
+ &blob, mem_ctx, array,
+ (ndr_push_flags_fn_t)ndr_push_messaging_array);
+
+ if (!NT_STATUS_IS_OK(status)) {
+ talloc_free(mem_ctx);
+ return status;
+ }
+
+ if (DEBUGLEVEL >= 10) {
+ DEBUG(10, ("messaging_tdb_store:\n"));
+ NDR_PRINT_DEBUG(messaging_array, array);
+ }
+
+ data.dptr = blob.data;
+ data.dsize = blob.length;
+
+ ret = tdb_store(msg_tdb, key, data, TDB_REPLACE);
+ TALLOC_FREE(mem_ctx);
+
+ return (ret == 0) ? NT_STATUS_OK : NT_STATUS_INTERNAL_DB_CORRUPTION;
+}
+
+/****************************************************************************
+ Notify a process that it has a message. If the process doesn't exist
+ then delete its record in the database.
+****************************************************************************/
+
+static NTSTATUS message_notify(struct server_id procid)
+{
+ pid_t pid = procid.pid;
+ int ret;
+ uid_t euid = geteuid();
+
+ /*
+ * Doing kill with a non-positive pid causes messages to be
+ * sent to places we don't want.
+ */
+
+ SMB_ASSERT(pid > 0);
+
+ if (euid != 0) {
+ /* If we're not root become so to send the message. */
+ save_re_uid();
+ set_effective_uid(0);
+ }
+
+ ret = kill(pid, SIGUSR1);
+
+ if (euid != 0) {
+ /* Go back to who we were. */
+ int saved_errno = errno;
+ restore_re_uid_fromroot();
+ errno = saved_errno;
+ }
+
+ if (ret == 0) {
+ return NT_STATUS_OK;
+ }
+
+ /*
+ * Something has gone wrong
+ */
+
+ DEBUG(2,("message to process %d failed - %s\n", (int)pid,
+ strerror(errno)));
+
+ /*
+ * No call to map_nt_error_from_unix -- don't want to link in
+ * errormap.o into lots of utils.
+ */
+
+ if (errno == ESRCH) return NT_STATUS_INVALID_HANDLE;
+ if (errno == EINVAL) return NT_STATUS_INVALID_PARAMETER;
+ if (errno == EPERM) return NT_STATUS_ACCESS_DENIED;
+ return NT_STATUS_UNSUCCESSFUL;
+}
+
+/****************************************************************************
+ Send a message to a particular pid.
+****************************************************************************/
+
+static NTSTATUS messaging_tdb_send(struct messaging_context *msg_ctx,
+ struct server_id pid, int msg_type,
+ const DATA_BLOB *data,
+ struct messaging_backend *backend)
+{
+ struct messaging_array *msg_array;
+ struct messaging_rec *rec;
+ TALLOC_CTX *mem_ctx;
+ NTSTATUS status;
+ TDB_DATA key = message_key_pid(pid);
+ TDB_CONTEXT *tdb = (TDB_CONTEXT *)backend->private_data;
+
+ /* NULL pointer means implicit length zero. */
+ if (!data->data) {
+ SMB_ASSERT(data->length == 0);
+ }
+
+ /*
+ * Doing kill with a non-positive pid causes messages to be
+ * sent to places we don't want.
+ */
+
+ SMB_ASSERT(procid_to_pid(&pid) > 0);
+
+ if (!(mem_ctx = talloc_init("message_send_pid"))) {
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ if (tdb_chainlock(tdb, key) == -1) {
+ TALLOC_FREE(mem_ctx);
+ return NT_STATUS_LOCK_NOT_GRANTED;
+ }
+
+ status = messaging_tdb_fetch(tdb, key, mem_ctx, &msg_array);
+
+ if (!NT_STATUS_IS_OK(status)) {
+ goto done;
+ }
+
+ if ((msg_type & MSG_FLAG_LOWPRIORITY)
+ && (msg_array->num_messages > 1000)) {
+ DEBUG(5, ("Dropping message for PID %s\n",
+ procid_str_static(&pid)));
+ status = NT_STATUS_INSUFFICIENT_RESOURCES;
+ goto done;
+ }
+
+ if (!(rec = TALLOC_REALLOC_ARRAY(mem_ctx, msg_array->messages,
+ struct messaging_rec,
+ msg_array->num_messages+1))) {
+ status = NT_STATUS_NO_MEMORY;
+ goto done;
+ }
+
+ rec[msg_array->num_messages].msg_version = MESSAGE_VERSION;
+ rec[msg_array->num_messages].msg_type = msg_type & MSG_TYPE_MASK;
+ rec[msg_array->num_messages].dest = pid;
+ rec[msg_array->num_messages].src = procid_self();
+ rec[msg_array->num_messages].buf = *data;
+
+ msg_array->messages = rec;
+ msg_array->num_messages += 1;
+
+ status = messaging_tdb_store(tdb, key, msg_array);
+
+ if (!NT_STATUS_IS_OK(status)) {
+ goto done;
+ }
+
+ status = message_notify(pid);
+
+ if (NT_STATUS_EQUAL(status, NT_STATUS_INVALID_HANDLE)) {
+ DEBUG(2, ("pid %s doesn't exist - deleting messages record\n",
+ procid_str_static(&pid)));
+ tdb_delete(tdb, message_key_pid(pid));
+ }
+
+ done:
+ tdb_chainunlock(tdb, key);
+ TALLOC_FREE(mem_ctx);
+ return status;
+}
+
+/****************************************************************************
+ Retrieve all messages for the current process.
+****************************************************************************/
+
+static NTSTATUS retrieve_all_messages(TDB_CONTEXT *msg_tdb,
+ TALLOC_CTX *mem_ctx,
+ struct messaging_array **presult)
+{
+ struct messaging_array *result;
+ TDB_DATA key = message_key_pid(procid_self());
+ NTSTATUS status;
+
+ if (tdb_chainlock(msg_tdb, key) == -1) {
+ return NT_STATUS_LOCK_NOT_GRANTED;
+ }
+
+ status = messaging_tdb_fetch(msg_tdb, key, mem_ctx, &result);
+
+ /*
+ * We delete the record here, tdb_set_max_dead keeps it around
+ */
+ tdb_delete(msg_tdb, key);
+ tdb_chainunlock(msg_tdb, key);
+
+ if (NT_STATUS_IS_OK(status)) {
+ *presult = result;
+ }
+
+ return status;
+}
+
+/****************************************************************************
+ Receive and dispatch any messages pending for this process.
+ JRA changed Dec 13 2006. Only one message handler now permitted per type.
+ *NOTE*: Dispatch functions must be able to cope with incoming
+ messages on an *odd* byte boundary.
+****************************************************************************/
+
+void message_dispatch(struct messaging_context *msg_ctx)
+{
+ struct messaging_array *msg_array = NULL;
+ TDB_CONTEXT *tdb = (TDB_CONTEXT *)(msg_ctx->local->private_data);
+ uint32 i;
+
+ if (!received_signal)
+ return;
+
+ DEBUG(10, ("message_dispatch: received_signal = %d\n",
+ received_signal));
+
+ received_signal = 0;
+
+ if (!NT_STATUS_IS_OK(retrieve_all_messages(tdb, NULL, &msg_array))) {
+ return;
+ }
+
+ for (i=0; i<msg_array->num_messages; i++) {
+ messaging_dispatch_rec(msg_ctx, &msg_array->messages[i]);
+ }
+
+ TALLOC_FREE(msg_array);
+}
+
+/** @} **/