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dbus/dbus/dbus-message.c
Havoc Pennington 2e3d1ea653 2005-08-09 Havoc Pennington <hp@redhat.com> 
* dbus/dbus-message.c (dbus_message_set_reply_serial): print
	warning if the reply serial is set to 0
2005-08-09 17:38:15 +00:00

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/* -*- mode: C; c-file-style: "gnu" -*- */
/* dbus-message.c DBusMessage object
*
* Copyright (C) 2002, 2003, 2004, 2005 Red Hat Inc.
* Copyright (C) 2002, 2003 CodeFactory AB
*
* Licensed under the Academic Free License version 2.1
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include "dbus-internals.h"
#include "dbus-marshal-recursive.h"
#include "dbus-marshal-validate.h"
#include "dbus-marshal-byteswap.h"
#include "dbus-marshal-header.h"
#include "dbus-signature.h"
#include "dbus-message-private.h"
#include "dbus-object-tree.h"
#include "dbus-memory.h"
#include "dbus-list.h"
#include "dbus-threads-internal.h"
#include <string.h>
/**
* @defgroup DBusMessageInternals DBusMessage implementation details
* @ingroup DBusInternals
* @brief DBusMessage private implementation details.
*
* The guts of DBusMessage and its methods.
*
* @{
*/
/* Not thread locked, but strictly const/read-only so should be OK
*/
/** An static string representing an empty signature */
_DBUS_STRING_DEFINE_STATIC(_dbus_empty_signature_str, "");
/* these have wacky values to help trap uninitialized iterators;
* but has to fit in 3 bits
*/
enum {
DBUS_MESSAGE_ITER_TYPE_READER = 3,
DBUS_MESSAGE_ITER_TYPE_WRITER = 7
};
/** typedef for internals of message iterator */
typedef struct DBusMessageRealIter DBusMessageRealIter;
/**
* @brief Internals of DBusMessageIter
*
* Object representing a position in a message. All fields are internal.
*/
struct DBusMessageRealIter
{
DBusMessage *message; /**< Message used */
dbus_uint32_t changed_stamp : CHANGED_STAMP_BITS; /**< stamp to detect invalid iters */
dbus_uint32_t iter_type : 3; /**< whether this is a reader or writer iter */
dbus_uint32_t sig_refcount : 8; /**< depth of open_signature() */
union
{
DBusTypeWriter writer; /**< writer */
DBusTypeReader reader; /**< reader */
} u; /**< the type writer or reader that does all the work */
};
static void
get_const_signature (DBusHeader *header,
const DBusString **type_str_p,
int *type_pos_p)
{
if (_dbus_header_get_field_raw (header,
DBUS_HEADER_FIELD_SIGNATURE,
type_str_p,
type_pos_p))
{
*type_pos_p += 1; /* skip the signature length which is 1 byte */
}
else
{
*type_str_p = &_dbus_empty_signature_str;
*type_pos_p = 0;
}
}
/**
* Swaps the message to compiler byte order if required
*
* @param message the message
*/
static void
_dbus_message_byteswap (DBusMessage *message)
{
const DBusString *type_str;
int type_pos;
if (message->byte_order == DBUS_COMPILER_BYTE_ORDER)
return;
_dbus_verbose ("Swapping message into compiler byte order\n");
get_const_signature (&message->header, &type_str, &type_pos);
_dbus_marshal_byteswap (type_str, type_pos,
message->byte_order,
DBUS_COMPILER_BYTE_ORDER,
&message->body, 0);
message->byte_order = DBUS_COMPILER_BYTE_ORDER;
_dbus_header_byteswap (&message->header, DBUS_COMPILER_BYTE_ORDER);
}
#define ensure_byte_order(message) \
if (message->byte_order != DBUS_COMPILER_BYTE_ORDER) \
_dbus_message_byteswap (message)
/**
* Gets the data to be sent over the network for this message.
* The header and then the body should be written out.
* This function is guaranteed to always return the same
* data once a message is locked (with _dbus_message_lock()).
*
* @param message the message.
* @param header return location for message header data.
* @param body return location for message body data.
*/
void
_dbus_message_get_network_data (DBusMessage *message,
const DBusString **header,
const DBusString **body)
{
_dbus_assert (message->locked);
*header = &message->header.data;
*body = &message->body;
}
/**
* Sets the serial number of a message.
* This can only be done once on a message.
*
* @param message the message
* @param serial the serial
*/
void
_dbus_message_set_serial (DBusMessage *message,
dbus_uint32_t serial)
{
_dbus_assert (message != NULL);
_dbus_assert (!message->locked);
_dbus_assert (dbus_message_get_serial (message) == 0);
_dbus_header_set_serial (&message->header, serial);
}
/**
* Adds a counter to be incremented immediately with the
* size of this message, and decremented by the size
* of this message when this message if finalized.
* The link contains a counter with its refcount already
* incremented, but the counter itself not incremented.
* Ownership of link and counter refcount is passed to
* the message.
*
* @param message the message
* @param link link with counter as data
*/
void
_dbus_message_add_size_counter_link (DBusMessage *message,
DBusList *link)
{
/* right now we don't recompute the delta when message
* size changes, and that's OK for current purposes
* I think, but could be important to change later.
* Do recompute it whenever there are no outstanding counters,
* since it's basically free.
*/
if (message->size_counters == NULL)
{
message->size_counter_delta =
_dbus_string_get_length (&message->header.data) +
_dbus_string_get_length (&message->body);
#if 0
_dbus_verbose ("message has size %ld\n",
message->size_counter_delta);
#endif
}
_dbus_list_append_link (&message->size_counters, link);
_dbus_counter_adjust (link->data, message->size_counter_delta);
}
/**
* Adds a counter to be incremented immediately with the
* size of this message, and decremented by the size
* of this message when this message if finalized.
*
* @param message the message
* @param counter the counter
* @returns #FALSE if no memory
*/
dbus_bool_t
_dbus_message_add_size_counter (DBusMessage *message,
DBusCounter *counter)
{
DBusList *link;
link = _dbus_list_alloc_link (counter);
if (link == NULL)
return FALSE;
_dbus_counter_ref (counter);
_dbus_message_add_size_counter_link (message, link);
return TRUE;
}
/**
* Removes a counter tracking the size of this message, and decrements
* the counter by the size of this message.
*
* @param message the message
* @param link_return return the link used
* @param counter the counter
*/
void
_dbus_message_remove_size_counter (DBusMessage *message,
DBusCounter *counter,
DBusList **link_return)
{
DBusList *link;
link = _dbus_list_find_last (&message->size_counters,
counter);
_dbus_assert (link != NULL);
_dbus_list_unlink (&message->size_counters,
link);
if (link_return)
*link_return = link;
else
_dbus_list_free_link (link);
_dbus_counter_adjust (counter, - message->size_counter_delta);
_dbus_counter_unref (counter);
}
/**
* Locks a message. Allows checking that applications don't keep a
* reference to a message in the outgoing queue and change it
* underneath us. Messages are locked when they enter the outgoing
* queue (dbus_connection_send_message()), and the library complains
* if the message is modified while locked.
*
* @param message the message to lock.
*/
void
_dbus_message_lock (DBusMessage *message)
{
if (!message->locked)
{
_dbus_header_update_lengths (&message->header,
_dbus_string_get_length (&message->body));
/* must have a signature if you have a body */
_dbus_assert (_dbus_string_get_length (&message->body) == 0 ||
dbus_message_get_signature (message) != NULL);
message->locked = TRUE;
}
}
static dbus_bool_t
set_or_delete_string_field (DBusMessage *message,
int field,
int typecode,
const char *value)
{
if (value == NULL)
return _dbus_header_delete_field (&message->header, field);
else
return _dbus_header_set_field_basic (&message->header,
field,
typecode,
&value);
}
#if 0
/* Probably we don't need to use this */
/**
* Sets the signature of the message, i.e. the arguments in the
* message payload. The signature includes only "in" arguments for
* #DBUS_MESSAGE_TYPE_METHOD_CALL and only "out" arguments for
* #DBUS_MESSAGE_TYPE_METHOD_RETURN, so is slightly different from
* what you might expect (it does not include the signature of the
* entire C++-style method).
*
* The signature is a string made up of type codes such as
* #DBUS_TYPE_INT32. The string is terminated with nul (nul is also
* the value of #DBUS_TYPE_INVALID). The macros such as
* #DBUS_TYPE_INT32 evaluate to integers; to assemble a signature you
* may find it useful to use the string forms, such as
* #DBUS_TYPE_INT32_AS_STRING.
*
* An "unset" or #NULL signature is considered the same as an empty
* signature. In fact dbus_message_get_signature() will never return
* #NULL.
*
* @param message the message
* @param signature the type signature or #NULL to unset
* @returns #FALSE if no memory
*/
static dbus_bool_t
_dbus_message_set_signature (DBusMessage *message,
const char *signature)
{
_dbus_return_val_if_fail (message != NULL, FALSE);
_dbus_return_val_if_fail (!message->locked, FALSE);
_dbus_return_val_if_fail (signature == NULL ||
_dbus_check_is_valid_signature (signature));
/* can't delete the signature if you have a message body */
_dbus_return_val_if_fail (_dbus_string_get_length (&message->body) == 0 ||
signature != NULL);
return set_or_delete_string_field (message,
DBUS_HEADER_FIELD_SIGNATURE,
DBUS_TYPE_SIGNATURE,
signature);
}
#endif
/** @} */
/**
* @defgroup DBusMessage DBusMessage
* @ingroup DBus
* @brief Message to be sent or received over a DBusConnection.
*
* A DBusMessage is the most basic unit of communication over a
* DBusConnection. A DBusConnection represents a stream of messages
* received from a remote application, and a stream of messages
* sent to a remote application.
*
* @{
*/
/**
* @typedef DBusMessage
*
* Opaque data type representing a message received from or to be
* sent to another application.
*/
/**
* Returns the serial of a message or 0 if none has been specified.
* The message's serial number is provided by the application sending
* the message and is used to identify replies to this message. All
* messages received on a connection will have a serial, but messages
* you haven't sent yet may return 0.
*
* @param message the message
* @returns the client serial
*/
dbus_uint32_t
dbus_message_get_serial (DBusMessage *message)
{
_dbus_return_val_if_fail (message != NULL, 0);
return _dbus_header_get_serial (&message->header);
}
/**
* Sets the reply serial of a message (the client serial
* of the message this is a reply to).
*
* @param message the message
* @param reply_serial the client serial
* @returns #FALSE if not enough memory
*/
dbus_bool_t
dbus_message_set_reply_serial (DBusMessage *message,
dbus_uint32_t reply_serial)
{
_dbus_return_val_if_fail (message != NULL, FALSE);
_dbus_return_val_if_fail (!message->locked, FALSE);
_dbus_return_val_if_fail (reply_serial != 0, FALSE); /* 0 is invalid */
return _dbus_header_set_field_basic (&message->header,
DBUS_HEADER_FIELD_REPLY_SERIAL,
DBUS_TYPE_UINT32,
&reply_serial);
}
/**
* Returns the serial that the message is a reply to or 0 if none.
*
* @param message the message
* @returns the reply serial
*/
dbus_uint32_t
dbus_message_get_reply_serial (DBusMessage *message)
{
dbus_uint32_t v_UINT32;
_dbus_return_val_if_fail (message != NULL, 0);
if (_dbus_header_get_field_basic (&message->header,
DBUS_HEADER_FIELD_REPLY_SERIAL,
DBUS_TYPE_UINT32,
&v_UINT32))
return v_UINT32;
else
return 0;
}
static void
free_size_counter (void *element,
void *data)
{
DBusCounter *counter = element;
DBusMessage *message = data;
_dbus_counter_adjust (counter, - message->size_counter_delta);
_dbus_counter_unref (counter);
}
static void
dbus_message_finalize (DBusMessage *message)
{
_dbus_assert (message->refcount.value == 0);
/* This calls application callbacks! */
_dbus_data_slot_list_free (&message->slot_list);
_dbus_list_foreach (&message->size_counters,
free_size_counter, message);
_dbus_list_clear (&message->size_counters);
_dbus_header_free (&message->header);
_dbus_string_free (&message->body);
_dbus_assert (message->refcount.value == 0);
dbus_free (message);
}
/* Message Cache
*
* We cache some DBusMessage to reduce the overhead of allocating
* them. In my profiling this consistently made about an 8%
* difference. It avoids the malloc for the message, the malloc for
* the slot list, the malloc for the header string and body string,
* and the associated free() calls. It does introduce another global
* lock which could be a performance issue in certain cases.
*
* For the echo client/server the round trip time goes from around
* .000077 to .000069 with the message cache on my laptop. The sysprof
* change is as follows (numbers are cumulative percentage):
*
* with message cache implemented as array as it is now (0.000069 per):
* new_empty_header 1.46
* mutex_lock 0.56 # i.e. _DBUS_LOCK(message_cache)
* mutex_unlock 0.25
* self 0.41
* unref 2.24
* self 0.68
* list_clear 0.43
* mutex_lock 0.33 # i.e. _DBUS_LOCK(message_cache)
* mutex_unlock 0.25
*
* with message cache implemented as list (0.000070 per roundtrip):
* new_empty_header 2.72
* list_pop_first 1.88
* unref 3.3
* list_prepend 1.63
*
* without cache (0.000077 per roundtrip):
* new_empty_header 6.7
* string_init_preallocated 3.43
* dbus_malloc 2.43
* dbus_malloc0 2.59
*
* unref 4.02
* string_free 1.82
* dbus_free 1.63
* dbus_free 0.71
*
* If you implement the message_cache with a list, the primary reason
* it's slower is that you add another thread lock (on the DBusList
* mempool).
*/
/** Avoid caching huge messages */
#define MAX_MESSAGE_SIZE_TO_CACHE 10 * _DBUS_ONE_KILOBYTE
/** Avoid caching too many messages */
#define MAX_MESSAGE_CACHE_SIZE 5
_DBUS_DEFINE_GLOBAL_LOCK (message_cache);
static DBusMessage *message_cache[MAX_MESSAGE_CACHE_SIZE];
static int message_cache_count = 0;
static dbus_bool_t message_cache_shutdown_registered = FALSE;
static void
dbus_message_cache_shutdown (void *data)
{
int i;
_DBUS_LOCK (message_cache);
i = 0;
while (i < MAX_MESSAGE_CACHE_SIZE)
{
if (message_cache[i])
dbus_message_finalize (message_cache[i]);
++i;
}
message_cache_count = 0;
message_cache_shutdown_registered = FALSE;
_DBUS_UNLOCK (message_cache);
}
/**
* Tries to get a message from the message cache. The retrieved
* message will have junk in it, so it still needs to be cleared out
* in dbus_message_new_empty_header()
*
* @returns the message, or #NULL if none cached
*/
static DBusMessage*
dbus_message_get_cached (void)
{
DBusMessage *message;
int i;
message = NULL;
_DBUS_LOCK (message_cache);
_dbus_assert (message_cache_count >= 0);
if (message_cache_count == 0)
{
_DBUS_UNLOCK (message_cache);
return NULL;
}
/* This is not necessarily true unless count > 0, and
* message_cache is uninitialized until the shutdown is
* registered
*/
_dbus_assert (message_cache_shutdown_registered);
i = 0;
while (i < MAX_MESSAGE_CACHE_SIZE)
{
if (message_cache[i])
{
message = message_cache[i];
message_cache[i] = NULL;
message_cache_count -= 1;
break;
}
++i;
}
_dbus_assert (message_cache_count >= 0);
_dbus_assert (i < MAX_MESSAGE_CACHE_SIZE);
_dbus_assert (message != NULL);
_DBUS_UNLOCK (message_cache);
_dbus_assert (message->refcount.value == 0);
_dbus_assert (message->size_counters == NULL);
return message;
}
/**
* Tries to cache a message, otherwise finalize it.
*
* @param message the message
*/
static void
dbus_message_cache_or_finalize (DBusMessage *message)
{
dbus_bool_t was_cached;
int i;
_dbus_assert (message->refcount.value == 0);
/* This calls application code and has to be done first thing
* without holding the lock
*/
_dbus_data_slot_list_clear (&message->slot_list);
_dbus_list_foreach (&message->size_counters,
free_size_counter, message);
_dbus_list_clear (&message->size_counters);
was_cached = FALSE;
_DBUS_LOCK (message_cache);
if (!message_cache_shutdown_registered)
{
_dbus_assert (message_cache_count == 0);
if (!_dbus_register_shutdown_func (dbus_message_cache_shutdown, NULL))
goto out;
i = 0;
while (i < MAX_MESSAGE_CACHE_SIZE)
{
message_cache[i] = NULL;
++i;
}
message_cache_shutdown_registered = TRUE;
}
_dbus_assert (message_cache_count >= 0);
if ((_dbus_string_get_length (&message->header.data) +
_dbus_string_get_length (&message->body)) >
MAX_MESSAGE_SIZE_TO_CACHE)
goto out;
if (message_cache_count >= MAX_MESSAGE_CACHE_SIZE)
goto out;
/* Find empty slot */
i = 0;
while (message_cache[i] != NULL)
++i;
_dbus_assert (i < MAX_MESSAGE_CACHE_SIZE);
_dbus_assert (message_cache[i] == NULL);
message_cache[i] = message;
message_cache_count += 1;
was_cached = TRUE;
#ifndef DBUS_DISABLE_CHECKS
message->in_cache = TRUE;
#endif
out:
_DBUS_UNLOCK (message_cache);
_dbus_assert (message->refcount.value == 0);
if (!was_cached)
dbus_message_finalize (message);
}
static DBusMessage*
dbus_message_new_empty_header (void)
{
DBusMessage *message;
dbus_bool_t from_cache;
message = dbus_message_get_cached ();
if (message != NULL)
{
from_cache = TRUE;
}
else
{
from_cache = FALSE;
message = dbus_new (DBusMessage, 1);
if (message == NULL)
return NULL;
#ifndef DBUS_DISABLE_CHECKS
message->generation = _dbus_current_generation;
#endif
}
message->refcount.value = 1;
message->byte_order = DBUS_COMPILER_BYTE_ORDER;
message->locked = FALSE;
#ifndef DBUS_DISABLE_CHECKS
message->in_cache = FALSE;
#endif
message->size_counters = NULL;
message->size_counter_delta = 0;
message->changed_stamp = 0;
if (!from_cache)
_dbus_data_slot_list_init (&message->slot_list);
if (from_cache)
{
_dbus_header_reinit (&message->header, message->byte_order);
_dbus_string_set_length (&message->body, 0);
}
else
{
if (!_dbus_header_init (&message->header, message->byte_order))
{
dbus_free (message);
return NULL;
}
if (!_dbus_string_init_preallocated (&message->body, 32))
{
_dbus_header_free (&message->header);
dbus_free (message);
return NULL;
}
}
return message;
}
/**
* Constructs a new message of the given message type.
* Types include #DBUS_MESSAGE_TYPE_METHOD_CALL,
* #DBUS_MESSAGE_TYPE_SIGNAL, and so forth.
*
* @param message_type type of message
* @returns new message or #NULL If no memory
*/
DBusMessage*
dbus_message_new (int message_type)
{
DBusMessage *message;
_dbus_return_val_if_fail (message_type != DBUS_MESSAGE_TYPE_INVALID, NULL);
message = dbus_message_new_empty_header ();
if (message == NULL)
return NULL;
if (!_dbus_header_create (&message->header,
message_type,
NULL, NULL, NULL, NULL, NULL))
{
dbus_message_unref (message);
return NULL;
}
return message;
}
/**
* Constructs a new message to invoke a method on a remote
* object. Returns #NULL if memory can't be allocated for the
* message. The destination may be #NULL in which case no destination
* is set; this is appropriate when using D-BUS in a peer-to-peer
* context (no message bus). The interface may be #NULL, which means
* that if multiple methods with the given name exist it is undefined
* which one will be invoked.
*
* @param destination name that the message should be sent to or #NULL
* @param path object path the message should be sent to
* @param interface interface to invoke method on
* @param method method to invoke
*
* @returns a new DBusMessage, free with dbus_message_unref()
* @see dbus_message_unref()
*/
DBusMessage*
dbus_message_new_method_call (const char *destination,
const char *path,
const char *interface,
const char *method)
{
DBusMessage *message;
_dbus_return_val_if_fail (path != NULL, NULL);
_dbus_return_val_if_fail (method != NULL, NULL);
_dbus_return_val_if_fail (destination == NULL ||
_dbus_check_is_valid_bus_name (destination), NULL);
_dbus_return_val_if_fail (_dbus_check_is_valid_path (path), NULL);
_dbus_return_val_if_fail (interface == NULL ||
_dbus_check_is_valid_interface (interface), NULL);
_dbus_return_val_if_fail (_dbus_check_is_valid_member (method), NULL);
message = dbus_message_new_empty_header ();
if (message == NULL)
return NULL;
if (!_dbus_header_create (&message->header,
DBUS_MESSAGE_TYPE_METHOD_CALL,
destination, path, interface, method, NULL))
{
dbus_message_unref (message);
return NULL;
}
return message;
}
/**
* Constructs a message that is a reply to a method call. Returns
* #NULL if memory can't be allocated for the message.
*
* @param method_call the message which the created
* message is a reply to.
* @returns a new DBusMessage, free with dbus_message_unref()
* @see dbus_message_new_method_call(), dbus_message_unref()
*/
DBusMessage*
dbus_message_new_method_return (DBusMessage *method_call)
{
DBusMessage *message;
const char *sender;
_dbus_return_val_if_fail (method_call != NULL, NULL);
sender = dbus_message_get_sender (method_call);
/* sender is allowed to be null here in peer-to-peer case */
message = dbus_message_new_empty_header ();
if (message == NULL)
return NULL;
if (!_dbus_header_create (&message->header,
DBUS_MESSAGE_TYPE_METHOD_RETURN,
sender, NULL, NULL, NULL, NULL))
{
dbus_message_unref (message);
return NULL;
}
dbus_message_set_no_reply (message, TRUE);
if (!dbus_message_set_reply_serial (message,
dbus_message_get_serial (method_call)))
{
dbus_message_unref (message);
return NULL;
}
return message;
}
/**
* Constructs a new message representing a signal emission. Returns
* #NULL if memory can't be allocated for the message. A signal is
* identified by its originating interface, and the name of the
* signal.
*
* @param path the path to the object emitting the signal
* @param interface the interface the signal is emitted from
* @param name name of the signal
* @returns a new DBusMessage, free with dbus_message_unref()
* @see dbus_message_unref()
*/
DBusMessage*
dbus_message_new_signal (const char *path,
const char *interface,
const char *name)
{
DBusMessage *message;
_dbus_return_val_if_fail (path != NULL, NULL);
_dbus_return_val_if_fail (interface != NULL, NULL);
_dbus_return_val_if_fail (name != NULL, NULL);
_dbus_return_val_if_fail (_dbus_check_is_valid_path (path), NULL);
_dbus_return_val_if_fail (_dbus_check_is_valid_interface (interface), NULL);
_dbus_return_val_if_fail (_dbus_check_is_valid_member (name), NULL);
message = dbus_message_new_empty_header ();
if (message == NULL)
return NULL;
if (!_dbus_header_create (&message->header,
DBUS_MESSAGE_TYPE_SIGNAL,
NULL, path, interface, name, NULL))
{
dbus_message_unref (message);
return NULL;
}
dbus_message_set_no_reply (message, TRUE);
return message;
}
/**
* Creates a new message that is an error reply to a certain message.
* Error replies are possible in response to method calls primarily.
*
* @param reply_to the original message
* @param error_name the error name
* @param error_message the error message string or #NULL for none
* @returns a new error message
*/
DBusMessage*
dbus_message_new_error (DBusMessage *reply_to,
const char *error_name,
const char *error_message)
{
DBusMessage *message;
const char *sender;
DBusMessageIter iter;
_dbus_return_val_if_fail (reply_to != NULL, NULL);
_dbus_return_val_if_fail (error_name != NULL, NULL);
_dbus_return_val_if_fail (_dbus_check_is_valid_error_name (error_name), NULL);
sender = dbus_message_get_sender (reply_to);
/* sender may be NULL for non-message-bus case or
* when the message bus is dealing with an unregistered
* connection.
*/
message = dbus_message_new_empty_header ();
if (message == NULL)
return NULL;
if (!_dbus_header_create (&message->header,
DBUS_MESSAGE_TYPE_ERROR,
sender, NULL, NULL, NULL, error_name))
{
dbus_message_unref (message);
return NULL;
}
dbus_message_set_no_reply (message, TRUE);
if (!dbus_message_set_reply_serial (message,
dbus_message_get_serial (reply_to)))
{
dbus_message_unref (message);
return NULL;
}
if (error_message != NULL)
{
dbus_message_iter_init_append (message, &iter);
if (!dbus_message_iter_append_basic (&iter,
DBUS_TYPE_STRING,
&error_message))
{
dbus_message_unref (message);
return NULL;
}
}
return message;
}
/**
* Creates a new message that is an error reply to a certain message.
* Error replies are possible in response to method calls primarily.
*
* @param reply_to the original message
* @param error_name the error name
* @param error_format the error message format as with printf
* @param ... format string arguments
* @returns a new error message
*/
DBusMessage*
dbus_message_new_error_printf (DBusMessage *reply_to,
const char *error_name,
const char *error_format,
...)
{
va_list args;
DBusString str;
DBusMessage *message;
_dbus_return_val_if_fail (reply_to != NULL, NULL);
_dbus_return_val_if_fail (error_name != NULL, NULL);
_dbus_return_val_if_fail (_dbus_check_is_valid_error_name (error_name), NULL);
if (!_dbus_string_init (&str))
return NULL;
va_start (args, error_format);
if (_dbus_string_append_printf_valist (&str, error_format, args))
message = dbus_message_new_error (reply_to, error_name,
_dbus_string_get_const_data (&str));
else
message = NULL;
_dbus_string_free (&str);
va_end (args);
return message;
}
/**
* Creates a new message that is an exact replica of the message
* specified, except that its refcount is set to 1, its message serial
* is reset to 0, and if the original message was "locked" (in the
* outgoing message queue and thus not modifiable) the new message
* will not be locked.
*
* @param message the message.
* @returns the new message.
*/
DBusMessage *
dbus_message_copy (const DBusMessage *message)
{
DBusMessage *retval;
_dbus_return_val_if_fail (message != NULL, NULL);
retval = dbus_new0 (DBusMessage, 1);
if (retval == NULL)
return NULL;
retval->refcount.value = 1;
retval->byte_order = message->byte_order;
retval->locked = FALSE;
#ifndef DBUS_DISABLE_CHECKS
retval->generation = message->generation;
#endif
if (!_dbus_header_copy (&message->header, &retval->header))
{
dbus_free (retval);
return NULL;
}
if (!_dbus_string_init_preallocated (&retval->body,
_dbus_string_get_length (&message->body)))
{
_dbus_header_free (&retval->header);
dbus_free (retval);
return NULL;
}
if (!_dbus_string_copy (&message->body, 0,
&retval->body, 0))
goto failed_copy;
return retval;
failed_copy:
_dbus_header_free (&retval->header);
_dbus_string_free (&retval->body);
dbus_free (retval);
return NULL;
}
/**
* Increments the reference count of a DBusMessage.
*
* @param message The message
* @returns the message
* @see dbus_message_unref
*/
DBusMessage *
dbus_message_ref (DBusMessage *message)
{
dbus_int32_t old_refcount;
_dbus_return_val_if_fail (message != NULL, NULL);
_dbus_return_val_if_fail (message->generation == _dbus_current_generation, NULL);
_dbus_return_val_if_fail (!message->in_cache, NULL);
old_refcount = _dbus_atomic_inc (&message->refcount);
_dbus_assert (old_refcount >= 1);
return message;
}
/**
* Decrements the reference count of a DBusMessage.
*
* @param message The message
* @see dbus_message_ref
*/
void
dbus_message_unref (DBusMessage *message)
{
dbus_int32_t old_refcount;
_dbus_return_if_fail (message != NULL);
_dbus_return_if_fail (message->generation == _dbus_current_generation);
_dbus_return_if_fail (!message->in_cache);
old_refcount = _dbus_atomic_dec (&message->refcount);
_dbus_assert (old_refcount >= 0);
if (old_refcount == 1)
{
/* Calls application callbacks! */
dbus_message_cache_or_finalize (message);
}
}
/**
* Gets the type of a message. Types include
* #DBUS_MESSAGE_TYPE_METHOD_CALL, #DBUS_MESSAGE_TYPE_METHOD_RETURN,
* #DBUS_MESSAGE_TYPE_ERROR, #DBUS_MESSAGE_TYPE_SIGNAL, but other
* types are allowed and all code must silently ignore messages of
* unknown type. DBUS_MESSAGE_TYPE_INVALID will never be returned,
* however.
*
*
* @param message the message
* @returns the type of the message
*/
int
dbus_message_get_type (DBusMessage *message)
{
_dbus_return_val_if_fail (message != NULL, DBUS_MESSAGE_TYPE_INVALID);
return _dbus_header_get_message_type (&message->header);
}
/**
* Appends fields to a message given a variable argument list. The
* variable argument list should contain the type of each argument
* followed by the value to append. Appendable types are basic types,
* and arrays of fixed-length basic types. To append variable-length
* basic types, or any more complex value, you have to use an iterator
* rather than this function.
*
* To append a basic type, specify its type code followed by the
* address of the value. For example:
*
* @code
*
* dbus_int32_t v_INT32 = 42;
* const char *v_STRING = "Hello World";
* DBUS_TYPE_INT32, &v_INT32,
* DBUS_TYPE_STRING, &v_STRING,
* @endcode
*
* To append an array of fixed-length basic types, pass in the
* DBUS_TYPE_ARRAY typecode, the element typecode, the address of
* the array pointer, and a 32-bit integer giving the number of
* elements in the array. So for example:
* @code
* const dbus_int32_t array[] = { 1, 2, 3 };
* const dbus_int32_t *v_ARRAY = array;
* DBUS_TYPE_ARRAY, DBUS_TYPE_INT32, &v_ARRAY, 3
* @endcode
*
* @warning in C, given "int array[]", "&array == array" (the
* comp.lang.c FAQ says otherwise, but gcc and the FAQ don't agree).
* So if you're using an array instead of a pointer you have to create
* a pointer variable, assign the array to it, then take the address
* of the pointer variable. For strings it works to write
* const char *array = "Hello" and then use &array though.
*
* The last argument to this function must be #DBUS_TYPE_INVALID,
* marking the end of the argument list.
*
* String/signature/path arrays should be passed in as "const char***
* address_of_array" and "int n_elements"
*
* @todo support DBUS_TYPE_STRUCT and DBUS_TYPE_VARIANT and complex arrays
*
* @todo If this fails due to lack of memory, the message is hosed and
* you have to start over building the whole message.
*
* @param message the message
* @param first_arg_type type of the first argument
* @param ... value of first argument, list of additional type-value pairs
* @returns #TRUE on success
*/
dbus_bool_t
dbus_message_append_args (DBusMessage *message,
int first_arg_type,
...)
{
dbus_bool_t retval;
va_list var_args;
_dbus_return_val_if_fail (message != NULL, FALSE);
va_start (var_args, first_arg_type);
retval = dbus_message_append_args_valist (message,
first_arg_type,
var_args);
va_end (var_args);
return retval;
}
/**
* This function takes a va_list for use by language bindings.
* It's otherwise the same as dbus_message_append_args().
*
* @todo for now, if this function fails due to OOM it will leave
* the message half-written and you have to discard the message
* and start over.
*
* @see dbus_message_append_args.
* @param message the message
* @param first_arg_type type of first argument
* @param var_args value of first argument, then list of type/value pairs
* @returns #TRUE on success
*/
dbus_bool_t
dbus_message_append_args_valist (DBusMessage *message,
int first_arg_type,
va_list var_args)
{
int type;
DBusMessageIter iter;
_dbus_return_val_if_fail (message != NULL, FALSE);
type = first_arg_type;
dbus_message_iter_init_append (message, &iter);
while (type != DBUS_TYPE_INVALID)
{
if (dbus_type_is_basic (type))
{
const DBusBasicValue *value;
value = va_arg (var_args, const DBusBasicValue*);
if (!dbus_message_iter_append_basic (&iter,
type,
value))
goto failed;
}
else if (type == DBUS_TYPE_ARRAY)
{
int element_type;
DBusMessageIter array;
char buf[2];
element_type = va_arg (var_args, int);
buf[0] = element_type;
buf[1] = '\0';
if (!dbus_message_iter_open_container (&iter,
DBUS_TYPE_ARRAY,
buf,
&array))
goto failed;
if (dbus_type_is_fixed (element_type))
{
const DBusBasicValue **value;
int n_elements;
value = va_arg (var_args, const DBusBasicValue**);
n_elements = va_arg (var_args, int);
if (!dbus_message_iter_append_fixed_array (&array,
element_type,
value,
n_elements))
goto failed;
}
else if (element_type == DBUS_TYPE_STRING ||
element_type == DBUS_TYPE_SIGNATURE ||
element_type == DBUS_TYPE_OBJECT_PATH)
{
const char ***value_p;
const char **value;
int n_elements;
int i;
value_p = va_arg (var_args, const char***);
n_elements = va_arg (var_args, int);
value = *value_p;
i = 0;
while (i < n_elements)
{
if (!dbus_message_iter_append_basic (&array,
element_type,
&value[i]))
goto failed;
++i;
}
}
else
{
_dbus_warn ("arrays of %s can't be appended with %s for now\n",
_dbus_type_to_string (element_type),
_DBUS_FUNCTION_NAME);
goto failed;
}
if (!dbus_message_iter_close_container (&iter, &array))
goto failed;
}
#ifndef DBUS_DISABLE_CHECKS
else
{
_dbus_warn ("type %s isn't supported yet in %s\n",
_dbus_type_to_string (type), _DBUS_FUNCTION_NAME);
goto failed;
}
#endif
type = va_arg (var_args, int);
}
return TRUE;
failed:
return FALSE;
}
/**
* Gets arguments from a message given a variable argument list. The
* supported types include those supported by
* dbus_message_append_args(); that is, basic types and arrays of
* fixed-length basic types. The arguments are the same as they would
* be for dbus_message_iter_get_basic() or
* dbus_message_iter_get_fixed_array().
*
* In addition to those types, arrays of string, object path, and
* signature are supported; but these are returned as allocated memory
* and must be freed with dbus_free_string_array(), while the other
* types are returned as const references. To get a string array
* pass in "char ***array_location" and "int *n_elements"
*
* The variable argument list should contain the type of the argument
* followed by a pointer to where the value should be stored. The list
* is terminated with #DBUS_TYPE_INVALID.
*
* The returned values are constant; do not free them. They point
* into the #DBusMessage.
*
* If the requested arguments are not present, or do not have the
* requested types, then an error will be set.
*
* @todo support DBUS_TYPE_STRUCT and DBUS_TYPE_VARIANT and complex arrays
*
* @param message the message
* @param error error to be filled in on failure
* @param first_arg_type the first argument type
* @param ... location for first argument value, then list of type-location pairs
* @returns #FALSE if the error was set
*/
dbus_bool_t
dbus_message_get_args (DBusMessage *message,
DBusError *error,
int first_arg_type,
...)
{
dbus_bool_t retval;
va_list var_args;
_dbus_return_val_if_fail (message != NULL, FALSE);
_dbus_return_val_if_error_is_set (error, FALSE);
va_start (var_args, first_arg_type);
retval = dbus_message_get_args_valist (message, error, first_arg_type, var_args);
va_end (var_args);
return retval;
}
/**
* This function takes a va_list for use by language bindings. It is
* otherwise the same as dbus_message_get_args().
*
* @see dbus_message_get_args
* @param message the message
* @param error error to be filled in
* @param first_arg_type type of the first argument
* @param var_args return location for first argument, followed by list of type/location pairs
* @returns #FALSE if error was set
*/
dbus_bool_t
dbus_message_get_args_valist (DBusMessage *message,
DBusError *error,
int first_arg_type,
va_list var_args)
{
DBusMessageIter iter;
_dbus_return_val_if_fail (message != NULL, FALSE);
_dbus_return_val_if_error_is_set (error, FALSE);
dbus_message_iter_init (message, &iter);
return _dbus_message_iter_get_args_valist (&iter, error, first_arg_type, var_args);
}
static void
_dbus_message_iter_init_common (DBusMessage *message,
DBusMessageRealIter *real,
int iter_type)
{
_dbus_assert (sizeof (DBusMessageRealIter) <= sizeof (DBusMessageIter));
/* Since the iterator will read or write who-knows-what from the
* message, we need to get in the right byte order
*/
ensure_byte_order (message);
real->message = message;
real->changed_stamp = message->changed_stamp;
real->iter_type = iter_type;
real->sig_refcount = 0;
}
/**
* Initializes a #DBusMessageIter for reading the arguments of the
* message passed in.
*
* @param message the message
* @param iter pointer to an iterator to initialize
* @returns #FALSE if the message has no arguments
*/
dbus_bool_t
dbus_message_iter_init (DBusMessage *message,
DBusMessageIter *iter)
{
DBusMessageRealIter *real = (DBusMessageRealIter *)iter;
const DBusString *type_str;
int type_pos;
_dbus_return_val_if_fail (message != NULL, FALSE);
_dbus_return_val_if_fail (iter != NULL, FALSE);
get_const_signature (&message->header, &type_str, &type_pos);
_dbus_message_iter_init_common (message, real,
DBUS_MESSAGE_ITER_TYPE_READER);
_dbus_type_reader_init (&real->u.reader,
message->byte_order,
type_str, type_pos,
&message->body,
0);
return _dbus_type_reader_get_current_type (&real->u.reader) != DBUS_TYPE_INVALID;
}
#ifndef DBUS_DISABLE_CHECKS
static dbus_bool_t
_dbus_message_iter_check (DBusMessageRealIter *iter)
{
if (iter == NULL)
{
_dbus_warn ("dbus message iterator is NULL\n");
return FALSE;
}
if (iter->iter_type == DBUS_MESSAGE_ITER_TYPE_READER)
{
if (iter->u.reader.byte_order != iter->message->byte_order)
{
_dbus_warn ("dbus message changed byte order since iterator was created\n");
return FALSE;
}
/* because we swap the message into compiler order when you init an iter */
_dbus_assert (iter->u.reader.byte_order == DBUS_COMPILER_BYTE_ORDER);
}
else if (iter->iter_type == DBUS_MESSAGE_ITER_TYPE_WRITER)
{
if (iter->u.writer.byte_order != iter->message->byte_order)
{
_dbus_warn ("dbus message changed byte order since append iterator was created\n");
return FALSE;
}
/* because we swap the message into compiler order when you init an iter */
_dbus_assert (iter->u.writer.byte_order == DBUS_COMPILER_BYTE_ORDER);
}
else
{
_dbus_warn ("dbus message iterator looks uninitialized or corrupted\n");
return FALSE;
}
if (iter->changed_stamp != iter->message->changed_stamp)
{
_dbus_warn ("dbus message iterator invalid because the message has been modified (or perhaps the iterator is just uninitialized)\n");
return FALSE;
}
return TRUE;
}
#endif /* DBUS_DISABLE_CHECKS */
/**
* Checks if an iterator has any more fields.
*
* @param iter the message iter
* @returns #TRUE if there are more fields
* following
*/
dbus_bool_t
dbus_message_iter_has_next (DBusMessageIter *iter)
{
DBusMessageRealIter *real = (DBusMessageRealIter *)iter;
_dbus_return_val_if_fail (_dbus_message_iter_check (real), FALSE);
_dbus_return_val_if_fail (real->iter_type == DBUS_MESSAGE_ITER_TYPE_READER, FALSE);
return _dbus_type_reader_has_next (&real->u.reader);
}
/**
* Moves the iterator to the next field, if any. If there's no next
* field, returns #FALSE. If the iterator moves forward, returns
* #TRUE.
*
* @param iter the message iter
* @returns #TRUE if the iterator was moved to the next field
*/
dbus_bool_t
dbus_message_iter_next (DBusMessageIter *iter)
{
DBusMessageRealIter *real = (DBusMessageRealIter *)iter;
_dbus_return_val_if_fail (_dbus_message_iter_check (real), FALSE);
_dbus_return_val_if_fail (real->iter_type == DBUS_MESSAGE_ITER_TYPE_READER, FALSE);
return _dbus_type_reader_next (&real->u.reader);
}
/**
* Returns the argument type of the argument that the message iterator
* points to. If the iterator is at the end of the message, returns
* #DBUS_TYPE_INVALID. You can thus write a loop as follows:
*
* @code
* dbus_message_iter_init (&iter);
* while ((current_type = dbus_message_iter_get_arg_type (&iter)) != DBUS_TYPE_INVALID)
* dbus_message_iter_next (&iter);
* @endcode
*
* @param iter the message iter
* @returns the argument type
*/
int
dbus_message_iter_get_arg_type (DBusMessageIter *iter)
{
DBusMessageRealIter *real = (DBusMessageRealIter *)iter;
_dbus_return_val_if_fail (_dbus_message_iter_check (real), DBUS_TYPE_INVALID);
_dbus_return_val_if_fail (real->iter_type == DBUS_MESSAGE_ITER_TYPE_READER, FALSE);
return _dbus_type_reader_get_current_type (&real->u.reader);
}
/**
* Returns the element type of the array that the message iterator
* points to. Note that you need to check that the iterator points to
* an array prior to using this function.
*
* @param iter the message iter
* @returns the array element type
*/
int
dbus_message_iter_get_element_type (DBusMessageIter *iter)
{
DBusMessageRealIter *real = (DBusMessageRealIter *)iter;
_dbus_return_val_if_fail (_dbus_message_iter_check (real), DBUS_TYPE_INVALID);
_dbus_return_val_if_fail (real->iter_type == DBUS_MESSAGE_ITER_TYPE_READER, DBUS_TYPE_INVALID);
_dbus_return_val_if_fail (dbus_message_iter_get_arg_type (iter) == DBUS_TYPE_ARRAY, DBUS_TYPE_INVALID);
return _dbus_type_reader_get_element_type (&real->u.reader);
}
/**
* Recurses into a container value when reading values from a message,
* initializing a sub-iterator to use for traversing the child values
* of the container.
*
* Note that this recurses into a value, not a type, so you can only
* recurse if the value exists. The main implication of this is that
* if you have for example an empty array of array of int32, you can
* recurse into the outermost array, but it will have no values, so
* you won't be able to recurse further. There's no array of int32 to
* recurse into.
*
* @param iter the message iterator
* @param sub the sub-iterator to initialize
*/
void
dbus_message_iter_recurse (DBusMessageIter *iter,
DBusMessageIter *sub)
{
DBusMessageRealIter *real = (DBusMessageRealIter *)iter;
DBusMessageRealIter *real_sub = (DBusMessageRealIter *)sub;
_dbus_return_if_fail (_dbus_message_iter_check (real));
_dbus_return_if_fail (sub != NULL);
*real_sub = *real;
_dbus_type_reader_recurse (&real->u.reader, &real_sub->u.reader);
}
/**
* Returns the current signature of a message iterator. This
* is useful primarily for dealing with variants; one can
* recurse into a variant and determine the signature of
* the variant's value.
*
* @param iter the message iterator
* @returns the contained signature, or NULL if out of memory
*/
char *
dbus_message_iter_get_signature (DBusMessageIter *iter)
{
const DBusString *sig;
DBusString retstr;
char *ret;
int start, len;
DBusMessageRealIter *real = (DBusMessageRealIter *)iter;
_dbus_return_val_if_fail (_dbus_message_iter_check (real), NULL);
if (!_dbus_string_init (&retstr))
return NULL;
_dbus_type_reader_get_signature (&real->u.reader, &sig,
&start, &len);
if (!_dbus_string_append_len (&retstr,
_dbus_string_get_const_data (sig) + start,
len))
return NULL;
if (!_dbus_string_steal_data (&retstr, &ret))
return NULL;
_dbus_string_free (&retstr);
return ret;
}
/**
* Reads a basic-typed value from the message iterator.
* Basic types are the non-containers such as integer and string.
*
* The value argument should be the address of a location to store
* the returned value. So for int32 it should be a "dbus_int32_t*"
* and for string a "const char**". The returned value is
* by reference and should not be freed.
*
* All returned values are guaranteed to fit in 8 bytes. So you can
* write code like this:
*
* @code
* #ifdef DBUS_HAVE_INT64
* dbus_uint64_t value;
* int type;
* dbus_message_iter_get_basic (&read_iter, &value);
* type = dbus_message_iter_get_arg_type (&read_iter);
* dbus_message_iter_append_basic (&write_iter, type, &value);
* #endif
* @endcode
*
* To avoid the #DBUS_HAVE_INT64 conditional, create a struct or
* something that occupies at least 8 bytes, e.g. you could use a
* struct with two int32 values in it. dbus_uint64_t is just one
* example of a type that's large enough to hold any possible value.
*
* Be sure you have somehow checked that
* dbus_message_iter_get_arg_type() matches the type you are
* expecting, or you'll crash when you try to use an integer as a
* string or something.
*
* @param iter the iterator
* @param value location to store the value
*/
void
dbus_message_iter_get_basic (DBusMessageIter *iter,
void *value)
{
DBusMessageRealIter *real = (DBusMessageRealIter *)iter;
_dbus_return_if_fail (_dbus_message_iter_check (real));
_dbus_return_if_fail (value != NULL);
_dbus_type_reader_read_basic (&real->u.reader,
value);
}
/**
* Returns the number of elements in the array;
*
* @param iter the iterator
* @returns the number of elements in the array
*/
int
dbus_message_iter_get_array_len (DBusMessageIter *iter)
{
DBusMessageRealIter *real = (DBusMessageRealIter *)iter;
_dbus_return_val_if_fail (_dbus_message_iter_check (real), 0);
return _dbus_type_reader_get_array_length (&real->u.reader);
}
/**
* Reads a block of fixed-length values from the message iterator.
* Fixed-length values are those basic types that are not string-like,
* such as integers, bool, double. The block read will be from the
* current position in the array until the end of the array.
*
* This function should only be used if #dbus_type_is_fixed returns
* #TRUE for the element type.
*
* The value argument should be the address of a location to store the
* returned array. So for int32 it should be a "const dbus_int32_t**"
* The returned value is by reference and should not be freed.
*
* @param iter the iterator
* @param value location to store the block
* @param n_elements number of elements in the block
*/
void
dbus_message_iter_get_fixed_array (DBusMessageIter *iter,
void *value,
int *n_elements)
{
DBusMessageRealIter *real = (DBusMessageRealIter *)iter;
_dbus_return_if_fail (_dbus_message_iter_check (real));
_dbus_return_if_fail (value != NULL);
_dbus_return_if_fail (dbus_type_is_fixed (_dbus_type_reader_get_current_type (&real->u.reader)));
_dbus_type_reader_read_fixed_multi (&real->u.reader,
value, n_elements);
}
/**
* This function takes a va_list for use by language bindings and is
* otherwise the same as dbus_message_iter_get_args().
* dbus_message_get_args() is the place to go for complete
* documentation.
*
* @see dbus_message_get_args
* @param iter the message iter
* @param error error to be filled in
* @param first_arg_type type of the first argument
* @param var_args return location for first argument, followed by list of type/location pairs
* @returns #FALSE if error was set
*/
dbus_bool_t
_dbus_message_iter_get_args_valist (DBusMessageIter *iter,
DBusError *error,
int first_arg_type,
va_list var_args)
{
DBusMessageRealIter *real = (DBusMessageRealIter *)iter;
int spec_type, msg_type, i;
dbus_bool_t retval;
_dbus_assert (_dbus_message_iter_check (real));
retval = FALSE;
spec_type = first_arg_type;
i = 0;
while (spec_type != DBUS_TYPE_INVALID)
{
msg_type = dbus_message_iter_get_arg_type (iter);
if (msg_type != spec_type)
{
dbus_set_error (error, DBUS_ERROR_INVALID_ARGS,
"Argument %d is specified to be of type \"%s\", but "
"is actually of type \"%s\"\n", i,
_dbus_type_to_string (spec_type),
_dbus_type_to_string (msg_type));
goto out;
}
if (dbus_type_is_basic (spec_type))
{
DBusBasicValue *ptr;
ptr = va_arg (var_args, DBusBasicValue*);
_dbus_assert (ptr != NULL);
_dbus_type_reader_read_basic (&real->u.reader,
ptr);
}
else if (spec_type == DBUS_TYPE_ARRAY)
{
int element_type;
int spec_element_type;
const DBusBasicValue **ptr;
int *n_elements_p;
DBusTypeReader array;
spec_element_type = va_arg (var_args, int);
element_type = _dbus_type_reader_get_element_type (&real->u.reader);
if (spec_element_type != element_type)
{
dbus_set_error (error, DBUS_ERROR_INVALID_ARGS,
"Argument %d is specified to be an array of \"%s\", but "
"is actually an array of \"%s\"\n",
i,
_dbus_type_to_string (spec_element_type),
_dbus_type_to_string (element_type));
goto out;
}
if (dbus_type_is_fixed (spec_element_type))
{
ptr = va_arg (var_args, const DBusBasicValue**);
n_elements_p = va_arg (var_args, int*);
_dbus_assert (ptr != NULL);
_dbus_assert (n_elements_p != NULL);
_dbus_type_reader_recurse (&real->u.reader, &array);
_dbus_type_reader_read_fixed_multi (&array,
ptr, n_elements_p);
}
else if (spec_element_type == DBUS_TYPE_STRING ||
spec_element_type == DBUS_TYPE_SIGNATURE ||
spec_element_type == DBUS_TYPE_OBJECT_PATH)
{
char ***str_array_p;
int n_elements;
char **str_array;
str_array_p = va_arg (var_args, char***);
n_elements_p = va_arg (var_args, int*);
_dbus_assert (str_array_p != NULL);
_dbus_assert (n_elements_p != NULL);
/* Count elements in the array */
_dbus_type_reader_recurse (&real->u.reader, &array);
n_elements = 0;
while (_dbus_type_reader_get_current_type (&array) != DBUS_TYPE_INVALID)
{
++n_elements;
_dbus_type_reader_next (&array);
}
str_array = dbus_new0 (char*, n_elements + 1);
if (str_array == NULL)
{
_DBUS_SET_OOM (error);
goto out;
}
/* Now go through and dup each string */
_dbus_type_reader_recurse (&real->u.reader, &array);
i = 0;
while (i < n_elements)
{
const char *s;
_dbus_type_reader_read_basic (&array,
&s);
str_array[i] = _dbus_strdup (s);
if (str_array[i] == NULL)
{
dbus_free_string_array (str_array);
_DBUS_SET_OOM (error);
goto out;
}
++i;
if (!_dbus_type_reader_next (&array))
_dbus_assert (i == n_elements);
}
_dbus_assert (_dbus_type_reader_get_current_type (&array) == DBUS_TYPE_INVALID);
_dbus_assert (i == n_elements);
_dbus_assert (str_array[i] == NULL);
*str_array_p = str_array;
*n_elements_p = n_elements;
}
#ifndef DBUS_DISABLE_CHECKS
else
{
_dbus_warn ("you can't read arrays of container types (struct, variant, array) with %s for now\n",
_DBUS_FUNCTION_NAME);
goto out;
}
#endif
}
#ifndef DBUS_DISABLE_CHECKS
else
{
_dbus_warn ("you can only read arrays and basic types with %s for now\n",
_DBUS_FUNCTION_NAME);
goto out;
}
#endif
spec_type = va_arg (var_args, int);
if (!_dbus_type_reader_next (&real->u.reader) && spec_type != DBUS_TYPE_INVALID)
{
dbus_set_error (error, DBUS_ERROR_INVALID_ARGS,
"Message has only %d arguments, but more were expected", i);
goto out;
}
i++;
}
retval = TRUE;
out:
return retval;
}
/**
* Initializes a #DBusMessageIter for appending arguments to the end
* of a message.
*
* @todo If appending any of the arguments fails due to lack of
* memory, generally the message is hosed and you have to start over
* building the whole message.
*
* @param message the message
* @param iter pointer to an iterator to initialize
*/
void
dbus_message_iter_init_append (DBusMessage *message,
DBusMessageIter *iter)
{
DBusMessageRealIter *real = (DBusMessageRealIter *)iter;
_dbus_return_if_fail (message != NULL);
_dbus_return_if_fail (iter != NULL);
_dbus_message_iter_init_common (message, real,
DBUS_MESSAGE_ITER_TYPE_WRITER);
/* We create the signature string and point iterators at it "on demand"
* when a value is actually appended. That means that init() never fails
* due to OOM.
*/
_dbus_type_writer_init_types_delayed (&real->u.writer,
message->byte_order,
&message->body,
_dbus_string_get_length (&message->body));
}
/**
* Creates a temporary signature string containing the current
* signature, stores it in the iterator, and points the iterator to
* the end of it. Used any time we write to the message.
*
* @param real an iterator without a type_str
* @returns #FALSE if no memory
*/
static dbus_bool_t
_dbus_message_iter_open_signature (DBusMessageRealIter *real)
{
DBusString *str;
const DBusString *current_sig;
int current_sig_pos;
_dbus_assert (real->iter_type == DBUS_MESSAGE_ITER_TYPE_WRITER);
if (real->u.writer.type_str != NULL)
{
_dbus_assert (real->sig_refcount > 0);
real->sig_refcount += 1;
return TRUE;
}
str = dbus_new (DBusString, 1);
if (str == NULL)
return FALSE;
if (!_dbus_header_get_field_raw (&real->message->header,
DBUS_HEADER_FIELD_SIGNATURE,
&current_sig, &current_sig_pos))
current_sig = NULL;
if (current_sig)
{
int current_len;
current_len = _dbus_string_get_byte (current_sig, current_sig_pos);
current_sig_pos += 1; /* move on to sig data */
if (!_dbus_string_init_preallocated (str, current_len + 4))
{
dbus_free (str);
return FALSE;
}
if (!_dbus_string_copy_len (current_sig, current_sig_pos, current_len,
str, 0))
{
_dbus_string_free (str);
dbus_free (str);
return FALSE;
}
}
else
{
if (!_dbus_string_init_preallocated (str, 4))
{
dbus_free (str);
return FALSE;
}
}
real->sig_refcount = 1;
_dbus_type_writer_add_types (&real->u.writer,
str, _dbus_string_get_length (str));
return TRUE;
}
/**
* Sets the new signature as the message signature, frees the
* signature string, and marks the iterator as not having a type_str
* anymore. Frees the signature even if it fails, so you can't
* really recover from failure. Kinda busted.
*
* @param real an iterator without a type_str
* @returns #FALSE if no memory
*/
static dbus_bool_t
_dbus_message_iter_close_signature (DBusMessageRealIter *real)
{
DBusString *str;
const char *v_STRING;
dbus_bool_t retval;
_dbus_assert (real->iter_type == DBUS_MESSAGE_ITER_TYPE_WRITER);
_dbus_assert (real->u.writer.type_str != NULL);
_dbus_assert (real->sig_refcount > 0);
real->sig_refcount -= 1;
if (real->sig_refcount > 0)
return TRUE;
_dbus_assert (real->sig_refcount == 0);
retval = TRUE;
str = real->u.writer.type_str;
v_STRING = _dbus_string_get_const_data (str);
if (!_dbus_header_set_field_basic (&real->message->header,
DBUS_HEADER_FIELD_SIGNATURE,
DBUS_TYPE_SIGNATURE,
&v_STRING))
retval = FALSE;
_dbus_type_writer_remove_types (&real->u.writer);
_dbus_string_free (str);
dbus_free (str);
return retval;
}
#ifndef DBUS_DISABLE_CHECKS
static dbus_bool_t
_dbus_message_iter_append_check (DBusMessageRealIter *iter)
{
if (!_dbus_message_iter_check (iter))
return FALSE;
if (iter->message->locked)
{
_dbus_warn ("dbus append iterator can't be used: message is locked (has already been sent)\n");
return FALSE;
}
return TRUE;
}
#endif /* DBUS_DISABLE_CHECKS */
/**
* Appends a basic-typed value to the message. The basic types are the
* non-container types such as integer and string.
*
* The "value" argument should be the address of a basic-typed value.
* So for string, const char**. For integer, dbus_int32_t*.
*
* @todo If this fails due to lack of memory, the message is hosed and
* you have to start over building the whole message.
*
* @param iter the append iterator
* @param type the type of the value
* @param value the address of the value
* @returns #FALSE if not enough memory
*/
dbus_bool_t
dbus_message_iter_append_basic (DBusMessageIter *iter,
int type,
const void *value)
{
DBusMessageRealIter *real = (DBusMessageRealIter *)iter;
dbus_bool_t ret;
_dbus_return_val_if_fail (_dbus_message_iter_append_check (real), FALSE);
_dbus_return_val_if_fail (real->iter_type == DBUS_MESSAGE_ITER_TYPE_WRITER, FALSE);
_dbus_return_val_if_fail (dbus_type_is_basic (type), FALSE);
_dbus_return_val_if_fail (value != NULL, FALSE);
if (!_dbus_message_iter_open_signature (real))
return FALSE;
ret = _dbus_type_writer_write_basic (&real->u.writer, type, value);
if (!_dbus_message_iter_close_signature (real))
ret = FALSE;
return ret;
}
/**
* Appends a block of fixed-length values to an array. The
* fixed-length types are all basic types that are not string-like. So
* int32, double, bool, etc. You must call
* dbus_message_iter_open_container() to open an array of values
* before calling this function. You may call this function multiple
* times (and intermixed with calls to
* dbus_message_iter_append_basic()) for the same array.
*
* The "value" argument should be the address of the array. So for
* integer, "dbus_int32_t**" is expected for example.
*
* @warning in C, given "int array[]", "&array == array" (the
* comp.lang.c FAQ says otherwise, but gcc and the FAQ don't agree).
* So if you're using an array instead of a pointer you have to create
* a pointer variable, assign the array to it, then take the address
* of the pointer variable.
* @code
* const dbus_int32_t array[] = { 1, 2, 3 };
* const dbus_int32_t *v_ARRAY = array;
* if (!dbus_message_iter_append_fixed_array (&iter, DBUS_TYPE_INT32, &v_ARRAY, 3))
* fprintf (stderr, "No memory!\n");
* @endcode
* For strings it works to write const char *array = "Hello" and then
* use &array though.
*
* @todo If this fails due to lack of memory, the message is hosed and
* you have to start over building the whole message.
*
* @param iter the append iterator
* @param element_type the type of the array elements
* @param value the address of the array
* @param n_elements the number of elements to append
* @returns #FALSE if not enough memory
*/
dbus_bool_t
dbus_message_iter_append_fixed_array (DBusMessageIter *iter,
int element_type,
const void *value,
int n_elements)
{
DBusMessageRealIter *real = (DBusMessageRealIter *)iter;
dbus_bool_t ret;
_dbus_return_val_if_fail (_dbus_message_iter_append_check (real), FALSE);
_dbus_return_val_if_fail (real->iter_type == DBUS_MESSAGE_ITER_TYPE_WRITER, FALSE);
_dbus_return_val_if_fail (dbus_type_is_fixed (element_type), FALSE);
_dbus_return_val_if_fail (real->u.writer.container_type == DBUS_TYPE_ARRAY, FALSE);
_dbus_return_val_if_fail (value != NULL, FALSE);
_dbus_return_val_if_fail (n_elements >= 0, FALSE);
_dbus_return_val_if_fail (n_elements <=
DBUS_MAXIMUM_ARRAY_LENGTH / _dbus_type_get_alignment (element_type),
FALSE);
ret = _dbus_type_writer_write_fixed_multi (&real->u.writer, element_type, value, n_elements);
return ret;
}
/**
* Appends a container-typed value to the message; you are required to
* append the contents of the container using the returned
* sub-iterator, and then call
* dbus_message_iter_close_container(). Container types are for
* example struct, variant, and array. For variants, the
* contained_signature should be the type of the single value inside
* the variant. For structs and dict entries, contained_signature
* should be #NULL; it will be set to whatever types you write into
* the struct. For arrays, contained_signature should be the type of
* the array elements.
*
* @todo If this fails due to lack of memory, the message is hosed and
* you have to start over building the whole message.
*
* @param iter the append iterator
* @param type the type of the value
* @param contained_signature the type of container contents
* @param sub sub-iterator to initialize
* @returns #FALSE if not enough memory
*/
dbus_bool_t
dbus_message_iter_open_container (DBusMessageIter *iter,
int type,
const char *contained_signature,
DBusMessageIter *sub)
{
DBusMessageRealIter *real = (DBusMessageRealIter *)iter;
DBusMessageRealIter *real_sub = (DBusMessageRealIter *)sub;
DBusString contained_str;
_dbus_return_val_if_fail (_dbus_message_iter_append_check (real), FALSE);
_dbus_return_val_if_fail (real->iter_type == DBUS_MESSAGE_ITER_TYPE_WRITER, FALSE);
_dbus_return_val_if_fail (dbus_type_is_container (type), FALSE);
_dbus_return_val_if_fail (sub != NULL, FALSE);
_dbus_return_val_if_fail ((type == DBUS_TYPE_STRUCT &&
contained_signature == NULL) ||
(type == DBUS_TYPE_DICT_ENTRY &&
contained_signature == NULL) ||
contained_signature != NULL, FALSE);
#if 0
/* FIXME this would fail if the contained_signature is a dict entry,
* since dict entries are invalid signatures standalone (they must be in
* an array)
*/
_dbus_return_val_if_fail (contained_signature == NULL ||
_dbus_check_is_valid_signature (contained_signature));
#endif
if (!_dbus_message_iter_open_signature (real))
return FALSE;
*real_sub = *real;
if (contained_signature != NULL)
{
_dbus_string_init_const (&contained_str, contained_signature);
return _dbus_type_writer_recurse (&real->u.writer,
type,
&contained_str, 0,
&real_sub->u.writer);
}
else
{
return _dbus_type_writer_recurse (&real->u.writer,
type,
NULL, 0,
&real_sub->u.writer);
}
}
/**
* Closes a container-typed value appended to the message; may write
* out more information to the message known only after the entire
* container is written, and may free resources created by
* dbus_message_iter_open_container().
*
* @todo If this fails due to lack of memory, the message is hosed and
* you have to start over building the whole message.
*
* @param iter the append iterator
* @param sub sub-iterator to close
* @returns #FALSE if not enough memory
*/
dbus_bool_t
dbus_message_iter_close_container (DBusMessageIter *iter,
DBusMessageIter *sub)
{
DBusMessageRealIter *real = (DBusMessageRealIter *)iter;
DBusMessageRealIter *real_sub = (DBusMessageRealIter *)sub;
dbus_bool_t ret;
_dbus_return_val_if_fail (_dbus_message_iter_append_check (real), FALSE);
_dbus_return_val_if_fail (real->iter_type == DBUS_MESSAGE_ITER_TYPE_WRITER, FALSE);
_dbus_return_val_if_fail (_dbus_message_iter_append_check (real_sub), FALSE);
_dbus_return_val_if_fail (real_sub->iter_type == DBUS_MESSAGE_ITER_TYPE_WRITER, FALSE);
ret = _dbus_type_writer_unrecurse (&real->u.writer,
&real_sub->u.writer);
if (!_dbus_message_iter_close_signature (real))
ret = FALSE;
return ret;
}
/**
* Sets a flag indicating that the message does not want a reply; if
* this flag is set, the other end of the connection may (but is not
* required to) optimize by not sending method return or error
* replies. If this flag is set, there is no way to know whether the
* message successfully arrived at the remote end. Normally you know a
* message was received when you receive the reply to it.
*
* @param message the message
* @param no_reply #TRUE if no reply is desired
*/
void
dbus_message_set_no_reply (DBusMessage *message,
dbus_bool_t no_reply)
{
_dbus_return_if_fail (message != NULL);
_dbus_return_if_fail (!message->locked);
_dbus_header_toggle_flag (&message->header,
DBUS_HEADER_FLAG_NO_REPLY_EXPECTED,
no_reply);
}
/**
* Returns #TRUE if the message does not expect
* a reply.
*
* @param message the message
* @returns #TRUE if the message sender isn't waiting for a reply
*/
dbus_bool_t
dbus_message_get_no_reply (DBusMessage *message)
{
_dbus_return_val_if_fail (message != NULL, FALSE);
return _dbus_header_get_flag (&message->header,
DBUS_HEADER_FLAG_NO_REPLY_EXPECTED);
}
/**
* Sets a flag indicating that an owner for the destination name will
* be automatically started before the message is delivered. When this
* flag is set, the message is held until a name owner finishes
* starting up, or fails to start up. In case of failure, the reply
* will be an error.
*
* @param message the message
* @param auto_start #TRUE if auto-starting is desired
*/
void
dbus_message_set_auto_start (DBusMessage *message,
dbus_bool_t auto_start)
{
_dbus_return_if_fail (message != NULL);
_dbus_return_if_fail (!message->locked);
_dbus_header_toggle_flag (&message->header,
DBUS_HEADER_FLAG_NO_AUTO_START,
!auto_start);
}
/**
* Returns #TRUE if the message will cause an owner for
* destination name to be auto-started.
*
* @param message the message
* @returns #TRUE if the message will use auto-start
*/
dbus_bool_t
dbus_message_get_auto_start (DBusMessage *message)
{
_dbus_return_val_if_fail (message != NULL, FALSE);
return !_dbus_header_get_flag (&message->header,
DBUS_HEADER_FLAG_NO_AUTO_START);
}
/**
* Sets the object path this message is being sent to (for
* DBUS_MESSAGE_TYPE_METHOD_CALL) or the one a signal is being
* emitted from (for DBUS_MESSAGE_TYPE_SIGNAL).
*
* @param message the message
* @param object_path the path or #NULL to unset
* @returns #FALSE if not enough memory
*/
dbus_bool_t
dbus_message_set_path (DBusMessage *message,
const char *object_path)
{
_dbus_return_val_if_fail (message != NULL, FALSE);
_dbus_return_val_if_fail (!message->locked, FALSE);
_dbus_return_val_if_fail (object_path == NULL ||
_dbus_check_is_valid_path (object_path),
FALSE);
return set_or_delete_string_field (message,
DBUS_HEADER_FIELD_PATH,
DBUS_TYPE_OBJECT_PATH,
object_path);
}
/**
* Gets the object path this message is being sent to (for
* DBUS_MESSAGE_TYPE_METHOD_CALL) or being emitted from (for
* DBUS_MESSAGE_TYPE_SIGNAL). Returns #NULL if none.
*
* @param message the message
* @returns the path (should not be freed) or #NULL
*/
const char*
dbus_message_get_path (DBusMessage *message)
{
const char *v;
_dbus_return_val_if_fail (message != NULL, NULL);
v = NULL; /* in case field doesn't exist */
_dbus_header_get_field_basic (&message->header,
DBUS_HEADER_FIELD_PATH,
DBUS_TYPE_OBJECT_PATH,
&v);
return v;
}
/**
* Checks if the message has a path
*
* @param message the message
* @param path the path name
* @returns #TRUE if there is a path field in the header
*/
dbus_bool_t
dbus_message_has_path (DBusMessage *message,
const char *path)
{
const char *msg_path;
msg_path = dbus_message_get_path (message);
if (msg_path == NULL)
{
if (path == NULL)
return TRUE;
else
return FALSE;
}
if (path == NULL)
return FALSE;
if (strcmp (msg_path, path) == 0)
return TRUE;
return FALSE;
}
/**
* Gets the object path this message is being sent to
* (for DBUS_MESSAGE_TYPE_METHOD_CALL) or being emitted
* from (for DBUS_MESSAGE_TYPE_SIGNAL) in a decomposed
* format (one array element per path component).
* Free the returned array with dbus_free_string_array().
*
* An empty but non-NULL path array means the path "/".
* So the path "/foo/bar" becomes { "foo", "bar", NULL }
* and the path "/" becomes { NULL }.
*
* @todo this could be optimized by using the len from the message
* instead of calling strlen() again
*
* @param message the message
* @param path place to store allocated array of path components; #NULL set here if no path field exists
* @returns #FALSE if no memory to allocate the array
*/
dbus_bool_t
dbus_message_get_path_decomposed (DBusMessage *message,
char ***path)
{
const char *v;
_dbus_return_val_if_fail (message != NULL, FALSE);
_dbus_return_val_if_fail (path != NULL, FALSE);
*path = NULL;
v = dbus_message_get_path (message);
if (v != NULL)
{
if (!_dbus_decompose_path (v, strlen (v),
path, NULL))
return FALSE;
}
return TRUE;
}
/**
* Sets the interface this message is being sent to
* (for DBUS_MESSAGE_TYPE_METHOD_CALL) or
* the interface a signal is being emitted from
* (for DBUS_MESSAGE_TYPE_SIGNAL).
*
* @param message the message
* @param interface the interface or #NULL to unset
* @returns #FALSE if not enough memory
*/
dbus_bool_t
dbus_message_set_interface (DBusMessage *message,
const char *interface)
{
_dbus_return_val_if_fail (message != NULL, FALSE);
_dbus_return_val_if_fail (!message->locked, FALSE);
_dbus_return_val_if_fail (interface == NULL ||
_dbus_check_is_valid_interface (interface),
FALSE);
return set_or_delete_string_field (message,
DBUS_HEADER_FIELD_INTERFACE,
DBUS_TYPE_STRING,
interface);
}
/**
* Gets the interface this message is being sent to
* (for DBUS_MESSAGE_TYPE_METHOD_CALL) or being emitted
* from (for DBUS_MESSAGE_TYPE_SIGNAL).
* The interface name is fully-qualified (namespaced).
* Returns #NULL if none.
*
* @param message the message
* @returns the message interface (should not be freed) or #NULL
*/
const char*
dbus_message_get_interface (DBusMessage *message)
{
const char *v;
_dbus_return_val_if_fail (message != NULL, NULL);
v = NULL; /* in case field doesn't exist */
_dbus_header_get_field_basic (&message->header,
DBUS_HEADER_FIELD_INTERFACE,
DBUS_TYPE_STRING,
&v);
return v;
}
/**
* Checks if the message has an interface
*
* @param message the message
* @param interface the interface name
* @returns #TRUE if there is a interface field in the header
*/
dbus_bool_t
dbus_message_has_interface (DBusMessage *message,
const char *interface)
{
const char *msg_interface;
msg_interface = dbus_message_get_interface (message);
if (msg_interface == NULL)
{
if (interface == NULL)
return TRUE;
else
return FALSE;
}
if (interface == NULL)
return FALSE;
if (strcmp (msg_interface, interface) == 0)
return TRUE;
return FALSE;
}
/**
* Sets the interface member being invoked
* (DBUS_MESSAGE_TYPE_METHOD_CALL) or emitted
* (DBUS_MESSAGE_TYPE_SIGNAL).
* The interface name is fully-qualified (namespaced).
*
* @param message the message
* @param member the member or #NULL to unset
* @returns #FALSE if not enough memory
*/
dbus_bool_t
dbus_message_set_member (DBusMessage *message,
const char *member)
{
_dbus_return_val_if_fail (message != NULL, FALSE);
_dbus_return_val_if_fail (!message->locked, FALSE);
_dbus_return_val_if_fail (member == NULL ||
_dbus_check_is_valid_member (member),
FALSE);
return set_or_delete_string_field (message,
DBUS_HEADER_FIELD_MEMBER,
DBUS_TYPE_STRING,
member);
}
/**
* Gets the interface member being invoked
* (DBUS_MESSAGE_TYPE_METHOD_CALL) or emitted
* (DBUS_MESSAGE_TYPE_SIGNAL). Returns #NULL if none.
*
* @param message the message
* @returns the member name (should not be freed) or #NULL
*/
const char*
dbus_message_get_member (DBusMessage *message)
{
const char *v;
_dbus_return_val_if_fail (message != NULL, NULL);
v = NULL; /* in case field doesn't exist */
_dbus_header_get_field_basic (&message->header,
DBUS_HEADER_FIELD_MEMBER,
DBUS_TYPE_STRING,
&v);
return v;
}
/**
* Checks if the message has an interface member
*
* @param message the message
* @param member the member name
* @returns #TRUE if there is a member field in the header
*/
dbus_bool_t
dbus_message_has_member (DBusMessage *message,
const char *member)
{
const char *msg_member;
msg_member = dbus_message_get_member (message);
if (msg_member == NULL)
{
if (member == NULL)
return TRUE;
else
return FALSE;
}
if (member == NULL)
return FALSE;
if (strcmp (msg_member, member) == 0)
return TRUE;
return FALSE;
}
/**
* Sets the name of the error (DBUS_MESSAGE_TYPE_ERROR).
* The name is fully-qualified (namespaced).
*
* @param message the message
* @param error_name the name or #NULL to unset
* @returns #FALSE if not enough memory
*/
dbus_bool_t
dbus_message_set_error_name (DBusMessage *message,
const char *error_name)
{
_dbus_return_val_if_fail (message != NULL, FALSE);
_dbus_return_val_if_fail (!message->locked, FALSE);
_dbus_return_val_if_fail (error_name == NULL ||
_dbus_check_is_valid_error_name (error_name),
FALSE);
return set_or_delete_string_field (message,
DBUS_HEADER_FIELD_ERROR_NAME,
DBUS_TYPE_STRING,
error_name);
}
/**
* Gets the error name (DBUS_MESSAGE_TYPE_ERROR only)
* or #NULL if none.
*
* @param message the message
* @returns the error name (should not be freed) or #NULL
*/
const char*
dbus_message_get_error_name (DBusMessage *message)
{
const char *v;
_dbus_return_val_if_fail (message != NULL, NULL);
v = NULL; /* in case field doesn't exist */
_dbus_header_get_field_basic (&message->header,
DBUS_HEADER_FIELD_ERROR_NAME,
DBUS_TYPE_STRING,
&v);
return v;
}
/**
* Sets the message's destination. The destination is the name of
* another connection on the bus and may be either the unique name
* assigned by the bus to each connection, or a well-known name
* specified in advance.
*
* @param message the message
* @param destination the destination name or #NULL to unset
* @returns #FALSE if not enough memory
*/
dbus_bool_t
dbus_message_set_destination (DBusMessage *message,
const char *destination)
{
_dbus_return_val_if_fail (message != NULL, FALSE);
_dbus_return_val_if_fail (!message->locked, FALSE);
_dbus_return_val_if_fail (destination == NULL ||
_dbus_check_is_valid_bus_name (destination),
FALSE);
return set_or_delete_string_field (message,
DBUS_HEADER_FIELD_DESTINATION,
DBUS_TYPE_STRING,
destination);
}
/**
* Gets the destination of a message or #NULL if there is none set.
*
* @param message the message
* @returns the message destination (should not be freed) or #NULL
*/
const char*
dbus_message_get_destination (DBusMessage *message)
{
const char *v;
_dbus_return_val_if_fail (message != NULL, NULL);
v = NULL; /* in case field doesn't exist */
_dbus_header_get_field_basic (&message->header,
DBUS_HEADER_FIELD_DESTINATION,
DBUS_TYPE_STRING,
&v);
return v;
}
/**
* Sets the message sender.
*
* @param message the message
* @param sender the sender or #NULL to unset
* @returns #FALSE if not enough memory
*/
dbus_bool_t
dbus_message_set_sender (DBusMessage *message,
const char *sender)
{
_dbus_return_val_if_fail (message != NULL, FALSE);
_dbus_return_val_if_fail (!message->locked, FALSE);
_dbus_return_val_if_fail (sender == NULL ||
_dbus_check_is_valid_bus_name (sender),
FALSE);
return set_or_delete_string_field (message,
DBUS_HEADER_FIELD_SENDER,
DBUS_TYPE_STRING,
sender);
}
/**
* Gets the unique name of the connection which originated this
* message, or #NULL if unknown or inapplicable. The sender is filled
* in by the message bus.
*
* @param message the message
* @returns the unique name of the sender or #NULL
*/
const char*
dbus_message_get_sender (DBusMessage *message)
{
const char *v;
_dbus_return_val_if_fail (message != NULL, NULL);
v = NULL; /* in case field doesn't exist */
_dbus_header_get_field_basic (&message->header,
DBUS_HEADER_FIELD_SENDER,
DBUS_TYPE_STRING,
&v);
return v;
}
/**
* Gets the type signature of the message, i.e. the arguments in the
* message payload. The signature includes only "in" arguments for
* #DBUS_MESSAGE_TYPE_METHOD_CALL and only "out" arguments for
* #DBUS_MESSAGE_TYPE_METHOD_RETURN, so is slightly different from
* what you might expect (it does not include the signature of the
* entire C++-style method).
*
* The signature is a string made up of type codes such as
* #DBUS_TYPE_INT32. The string is terminated with nul (nul is also
* the value of #DBUS_TYPE_INVALID).
*
* @param message the message
* @returns the type signature
*/
const char*
dbus_message_get_signature (DBusMessage *message)
{
const DBusString *type_str;
int type_pos;
_dbus_return_val_if_fail (message != NULL, NULL);
get_const_signature (&message->header, &type_str, &type_pos);
return _dbus_string_get_const_data_len (type_str, type_pos, 0);
}
static dbus_bool_t
_dbus_message_has_type_interface_member (DBusMessage *message,
int type,
const char *interface,
const char *member)
{
const char *n;
_dbus_assert (message != NULL);
_dbus_assert (interface != NULL);
_dbus_assert (member != NULL);
if (dbus_message_get_type (message) != type)
return FALSE;
/* Optimize by checking the short member name first
* instead of the longer interface name
*/
n = dbus_message_get_member (message);
if (n && strcmp (n, member) == 0)
{
n = dbus_message_get_interface (message);
if (n == NULL || strcmp (n, interface) == 0)
return TRUE;
}
return FALSE;
}
/**
* Checks whether the message is a method call with the given
* interface and member fields. If the message is not
* #DBUS_MESSAGE_TYPE_METHOD_CALL, or has a different interface or
* member field, returns #FALSE. If the interface field is missing,
* then it will be assumed equal to the provided interface. The D-BUS
* protocol allows method callers to leave out the interface name.
*
* @param message the message
* @param interface the name to check (must not be #NULL)
* @param method the name to check (must not be #NULL)
*
* @returns #TRUE if the message is the specified method call
*/
dbus_bool_t
dbus_message_is_method_call (DBusMessage *message,
const char *interface,
const char *method)
{
_dbus_return_val_if_fail (message != NULL, FALSE);
_dbus_return_val_if_fail (interface != NULL, FALSE);
_dbus_return_val_if_fail (method != NULL, FALSE);
/* don't check that interface/method are valid since it would be
* expensive, and not catch many common errors
*/
return _dbus_message_has_type_interface_member (message,
DBUS_MESSAGE_TYPE_METHOD_CALL,
interface, method);
}
/**
* Checks whether the message is a signal with the given interface and
* member fields. If the message is not #DBUS_MESSAGE_TYPE_SIGNAL, or
* has a different interface or member field, returns #FALSE. If the
* interface field in the message is missing, it is assumed to match
* any interface you pass in to this function.
*
* @param message the message
* @param interface the name to check (must not be #NULL)
* @param signal_name the name to check (must not be #NULL)
*
* @returns #TRUE if the message is the specified signal
*/
dbus_bool_t
dbus_message_is_signal (DBusMessage *message,
const char *interface,
const char *signal_name)
{
_dbus_return_val_if_fail (message != NULL, FALSE);
_dbus_return_val_if_fail (interface != NULL, FALSE);
_dbus_return_val_if_fail (signal_name != NULL, FALSE);
/* don't check that interface/name are valid since it would be
* expensive, and not catch many common errors
*/
return _dbus_message_has_type_interface_member (message,
DBUS_MESSAGE_TYPE_SIGNAL,
interface, signal_name);
}
/**
* Checks whether the message is an error reply with the given error
* name. If the message is not #DBUS_MESSAGE_TYPE_ERROR, or has a
* different name, returns #FALSE.
*
* @param message the message
* @param error_name the name to check (must not be #NULL)
*
* @returns #TRUE if the message is the specified error
*/
dbus_bool_t
dbus_message_is_error (DBusMessage *message,
const char *error_name)
{
const char *n;
_dbus_return_val_if_fail (message != NULL, FALSE);
_dbus_return_val_if_fail (error_name != NULL, FALSE);
/* don't check that error_name is valid since it would be expensive,
* and not catch many common errors
*/
if (dbus_message_get_type (message) != DBUS_MESSAGE_TYPE_ERROR)
return FALSE;
n = dbus_message_get_error_name (message);
if (n && strcmp (n, error_name) == 0)
return TRUE;
else
return FALSE;
}
/**
* Checks whether the message was sent to the given name. If the
* message has no destination specified or has a different
* destination, returns #FALSE.
*
* @param message the message
* @param name the name to check (must not be #NULL)
*
* @returns #TRUE if the message has the given destination name
*/
dbus_bool_t
dbus_message_has_destination (DBusMessage *message,
const char *name)
{
const char *s;
_dbus_return_val_if_fail (message != NULL, FALSE);
_dbus_return_val_if_fail (name != NULL, FALSE);
/* don't check that name is valid since it would be expensive, and
* not catch many common errors
*/
s = dbus_message_get_destination (message);
if (s && strcmp (s, name) == 0)
return TRUE;
else
return FALSE;
}
/**
* Checks whether the message has the given unique name as its sender.
* If the message has no sender specified or has a different sender,
* returns #FALSE. Note that a peer application will always have the
* unique name of the connection as the sender. So you can't use this
* function to see whether a sender owned a well-known name.
*
* Messages from the bus itself will have #DBUS_SERVICE_DBUS
* as the sender.
*
* @param message the message
* @param name the name to check (must not be #NULL)
*
* @returns #TRUE if the message has the given sender
*/
dbus_bool_t
dbus_message_has_sender (DBusMessage *message,
const char *name)
{
const char *s;
_dbus_return_val_if_fail (message != NULL, FALSE);
_dbus_return_val_if_fail (name != NULL, FALSE);
/* don't check that name is valid since it would be expensive, and
* not catch many common errors
*/
s = dbus_message_get_sender (message);
if (s && strcmp (s, name) == 0)
return TRUE;
else
return FALSE;
}
/**
* Checks whether the message has the given signature; see
* dbus_message_get_signature() for more details on what the signature
* looks like.
*
* @param message the message
* @param signature typecode array
* @returns #TRUE if message has the given signature
*/
dbus_bool_t
dbus_message_has_signature (DBusMessage *message,
const char *signature)
{
const char *s;
_dbus_return_val_if_fail (message != NULL, FALSE);
_dbus_return_val_if_fail (signature != NULL, FALSE);
/* don't check that signature is valid since it would be expensive,
* and not catch many common errors
*/
s = dbus_message_get_signature (message);
if (s && strcmp (s, signature) == 0)
return TRUE;
else
return FALSE;
}
/**
* Sets a #DBusError based on the contents of the given
* message. The error is only set if the message
* is an error message, as in DBUS_MESSAGE_TYPE_ERROR.
* The name of the error is set to the name of the message,
* and the error message is set to the first argument
* if the argument exists and is a string.
*
* The return value indicates whether the error was set (the error is
* set if and only if the message is an error message). So you can
* check for an error reply and convert it to DBusError in one go:
* @code
* if (dbus_set_error_from_message (error, reply))
* return error;
* else
* process reply;
* @endcode
*
* @param error the error to set
* @param message the message to set it from
* @returns #TRUE if dbus_message_get_is_error() returns #TRUE for the message
*/
dbus_bool_t
dbus_set_error_from_message (DBusError *error,
DBusMessage *message)
{
const char *str;
_dbus_return_val_if_fail (message != NULL, FALSE);
_dbus_return_val_if_error_is_set (error, FALSE);
if (dbus_message_get_type (message) != DBUS_MESSAGE_TYPE_ERROR)
return FALSE;
str = NULL;
dbus_message_get_args (message, NULL,
DBUS_TYPE_STRING, &str,
DBUS_TYPE_INVALID);
dbus_set_error (error, dbus_message_get_error_name (message),
str ? "%s" : NULL, str);
return TRUE;
}
/** @} */
/**
* @addtogroup DBusMessageInternals
*
* @{
*/
/**
* The initial buffer size of the message loader.
*
* @todo this should be based on min header size plus some average
* body size, or something. Or rather, the min header size only, if we
* want to try to read only the header, store that in a DBusMessage,
* then read only the body and store that, etc., depends on
* how we optimize _dbus_message_loader_get_buffer() and what
* the exact message format is.
*/
#define INITIAL_LOADER_DATA_LEN 32
/**
* Creates a new message loader. Returns #NULL if memory can't
* be allocated.
*
* @returns new loader, or #NULL.
*/
DBusMessageLoader*
_dbus_message_loader_new (void)
{
DBusMessageLoader *loader;
loader = dbus_new0 (DBusMessageLoader, 1);
if (loader == NULL)
return NULL;
loader->refcount = 1;
loader->corrupted = FALSE;
loader->corruption_reason = DBUS_VALID;
/* this can be configured by the app, but defaults to the protocol max */
loader->max_message_size = DBUS_MAXIMUM_MESSAGE_LENGTH;
if (!_dbus_string_init (&loader->data))
{
dbus_free (loader);
return NULL;
}
/* preallocate the buffer for speed, ignore failure */
_dbus_string_set_length (&loader->data, INITIAL_LOADER_DATA_LEN);
_dbus_string_set_length (&loader->data, 0);
return loader;
}
/**
* Increments the reference count of the loader.
*
* @param loader the loader.
* @returns the loader
*/
DBusMessageLoader *
_dbus_message_loader_ref (DBusMessageLoader *loader)
{
loader->refcount += 1;
return loader;
}
/**
* Decrements the reference count of the loader and finalizes the
* loader when the count reaches zero.
*
* @param loader the loader.
*/
void
_dbus_message_loader_unref (DBusMessageLoader *loader)
{
loader->refcount -= 1;
if (loader->refcount == 0)
{
_dbus_list_foreach (&loader->messages,
(DBusForeachFunction) dbus_message_unref,
NULL);
_dbus_list_clear (&loader->messages);
_dbus_string_free (&loader->data);
dbus_free (loader);
}
}
/**
* Gets the buffer to use for reading data from the network. Network
* data is read directly into an allocated buffer, which is then used
* in the DBusMessage, to avoid as many extra memcpy's as possible.
* The buffer must always be returned immediately using
* _dbus_message_loader_return_buffer(), even if no bytes are
* successfully read.
*
* @todo this function can be a lot more clever. For example
* it can probably always return a buffer size to read exactly
* the body of the next message, thus avoiding any memory wastage
* or reallocs.
*
* @todo we need to enforce a max length on strings in header fields.
*
* @param loader the message loader.
* @param buffer the buffer
*/
void
_dbus_message_loader_get_buffer (DBusMessageLoader *loader,
DBusString **buffer)
{
_dbus_assert (!loader->buffer_outstanding);
*buffer = &loader->data;
loader->buffer_outstanding = TRUE;
}
/**
* Returns a buffer obtained from _dbus_message_loader_get_buffer(),
* indicating to the loader how many bytes of the buffer were filled
* in. This function must always be called, even if no bytes were
* successfully read.
*
* @param loader the loader.
* @param buffer the buffer.
* @param bytes_read number of bytes that were read into the buffer.
*/
void
_dbus_message_loader_return_buffer (DBusMessageLoader *loader,
DBusString *buffer,
int bytes_read)
{
_dbus_assert (loader->buffer_outstanding);
_dbus_assert (buffer == &loader->data);
loader->buffer_outstanding = FALSE;
}
/*
* FIXME when we move the header out of the buffer, that memmoves all
* buffered messages. Kind of crappy.
*
* Also we copy the header and body, which is kind of crappy. To
* avoid this, we have to allow header and body to be in a single
* memory block, which is good for messages we read and bad for
* messages we are creating. But we could move_len() the buffer into
* this single memory block, and move_len() will just swap the buffers
* if you're moving the entire buffer replacing the dest string.
*
* We could also have the message loader tell the transport how many
* bytes to read; so it would first ask for some arbitrary number like
* 256, then if the message was incomplete it would use the
* header/body len to ask for exactly the size of the message (or
* blocks the size of a typical kernel buffer for the socket). That
* way we don't get trailing bytes in the buffer that have to be
* memmoved. Though I suppose we also don't have a chance of reading a
* bunch of small messages at once, so the optimization may be stupid.
*
* Another approach would be to keep a "start" index into
* loader->data and only delete it occasionally, instead of after
* each message is loaded.
*
* load_message() returns FALSE if not enough memory OR the loader was corrupted
*/
static dbus_bool_t
load_message (DBusMessageLoader *loader,
DBusMessage *message,
int byte_order,
int fields_array_len,
int header_len,
int body_len)
{
dbus_bool_t oom;
DBusValidity validity;
const DBusString *type_str;
int type_pos;
DBusValidationMode mode;
mode = DBUS_VALIDATION_MODE_DATA_IS_UNTRUSTED;
oom = FALSE;
#if 0
_dbus_verbose_bytes_of_string (&loader->data, 0, header_len /* + body_len */);
#endif
/* 1. VALIDATE AND COPY OVER HEADER */
_dbus_assert (_dbus_string_get_length (&message->header.data) == 0);
_dbus_assert ((header_len + body_len) <= _dbus_string_get_length (&loader->data));
if (!_dbus_header_load (&message->header,
mode,
&validity,
byte_order,
fields_array_len,
header_len,
body_len,
&loader->data, 0,
_dbus_string_get_length (&loader->data)))
{
_dbus_verbose ("Failed to load header for new message code %d\n", validity);
/* assert here so we can catch any code that still uses DBUS_VALID to indicate
oom errors. They should use DBUS_VALIDITY_UNKNOWN_OOM_ERROR instead */
_dbus_assert (validity != DBUS_VALID);
if (validity == DBUS_VALIDITY_UNKNOWN_OOM_ERROR)
oom = TRUE;
else
{
loader->corrupted = TRUE;
loader->corruption_reason = validity;
}
goto failed;
}
_dbus_assert (validity == DBUS_VALID);
message->byte_order = byte_order;
/* 2. VALIDATE BODY */
if (mode != DBUS_VALIDATION_MODE_WE_TRUST_THIS_DATA_ABSOLUTELY)
{
get_const_signature (&message->header, &type_str, &type_pos);
/* Because the bytes_remaining arg is NULL, this validates that the
* body is the right length
*/
validity = _dbus_validate_body_with_reason (type_str,
type_pos,
byte_order,
NULL,
&loader->data,
header_len,
body_len);
if (validity != DBUS_VALID)
{
_dbus_verbose ("Failed to validate message body code %d\n", validity);
loader->corrupted = TRUE;
loader->corruption_reason = validity;
goto failed;
}
}
/* 3. COPY OVER BODY AND QUEUE MESSAGE */
if (!_dbus_list_append (&loader->messages, message))
{
_dbus_verbose ("Failed to append new message to loader queue\n");
oom = TRUE;
goto failed;
}
_dbus_assert (_dbus_string_get_length (&message->body) == 0);
_dbus_assert (_dbus_string_get_length (&loader->data) >=
(header_len + body_len));
if (!_dbus_string_copy_len (&loader->data, header_len, body_len, &message->body, 0))
{
_dbus_verbose ("Failed to move body into new message\n");
oom = TRUE;
goto failed;
}
_dbus_string_delete (&loader->data, 0, header_len + body_len);
_dbus_assert (_dbus_string_get_length (&message->header.data) == header_len);
_dbus_assert (_dbus_string_get_length (&message->body) == body_len);
_dbus_verbose ("Loaded message %p\n", message);
_dbus_assert (!oom);
_dbus_assert (!loader->corrupted);
_dbus_assert (loader->messages != NULL);
_dbus_assert (_dbus_list_find_last (&loader->messages, message) != NULL);
return TRUE;
failed:
/* Clean up */
/* does nothing if the message isn't in the list */
_dbus_list_remove_last (&loader->messages, message);
if (oom)
_dbus_assert (!loader->corrupted);
else
_dbus_assert (loader->corrupted);
_dbus_verbose_bytes_of_string (&loader->data, 0, _dbus_string_get_length (&loader->data));
return FALSE;
}
/**
* Converts buffered data into messages, if we have enough data. If
* we don't have enough data, does nothing.
*
* @todo we need to check that the proper named header fields exist
* for each message type.
*
* @todo If a message has unknown type, we should probably eat it
* right here rather than passing it out to applications. However
* it's not an error to see messages of unknown type.
*
* @param loader the loader.
* @returns #TRUE if we had enough memory to finish.
*/
dbus_bool_t
_dbus_message_loader_queue_messages (DBusMessageLoader *loader)
{
while (!loader->corrupted &&
_dbus_string_get_length (&loader->data) >= DBUS_MINIMUM_HEADER_SIZE)
{
DBusValidity validity;
int byte_order, fields_array_len, header_len, body_len;
if (_dbus_header_have_message_untrusted (loader->max_message_size,
&validity,
&byte_order,
&fields_array_len,
&header_len,
&body_len,
&loader->data, 0,
_dbus_string_get_length (&loader->data)))
{
DBusMessage *message;
_dbus_assert (validity == DBUS_VALID);
message = dbus_message_new_empty_header ();
if (message == NULL)
return FALSE;
if (!load_message (loader, message,
byte_order, fields_array_len,
header_len, body_len))
{
dbus_message_unref (message);
/* load_message() returns false if corrupted or OOM; if
* corrupted then return TRUE for not OOM
*/
return loader->corrupted;
}
_dbus_assert (loader->messages != NULL);
_dbus_assert (_dbus_list_find_last (&loader->messages, message) != NULL);
}
else
{
_dbus_verbose ("Initial peek at header says we don't have a whole message yet, or data broken with invalid code %d\n",
validity);
if (validity != DBUS_VALID)
{
loader->corrupted = TRUE;
loader->corruption_reason = validity;
}
return TRUE;
}
}
return TRUE;
}
/**
* Peeks at first loaded message, returns #NULL if no messages have
* been queued.
*
* @param loader the loader.
* @returns the next message, or #NULL if none.
*/
DBusMessage*
_dbus_message_loader_peek_message (DBusMessageLoader *loader)
{
if (loader->messages)
return loader->messages->data;
else
return NULL;
}
/**
* Pops a loaded message (passing ownership of the message
* to the caller). Returns #NULL if no messages have been
* queued.
*
* @param loader the loader.
* @returns the next message, or #NULL if none.
*/
DBusMessage*
_dbus_message_loader_pop_message (DBusMessageLoader *loader)
{
return _dbus_list_pop_first (&loader->messages);
}
/**
* Pops a loaded message inside a list link (passing ownership of the
* message and link to the caller). Returns #NULL if no messages have
* been loaded.
*
* @param loader the loader.
* @returns the next message link, or #NULL if none.
*/
DBusList*
_dbus_message_loader_pop_message_link (DBusMessageLoader *loader)
{
return _dbus_list_pop_first_link (&loader->messages);
}
/**
* Returns a popped message link, used to undo a pop.
*
* @param loader the loader
* @param link the link with a message in it
*/
void
_dbus_message_loader_putback_message_link (DBusMessageLoader *loader,
DBusList *link)
{
_dbus_list_prepend_link (&loader->messages, link);
}
/**
* Checks whether the loader is confused due to bad data.
* If messages are received that are invalid, the
* loader gets confused and gives up permanently.
* This state is called "corrupted."
*
* @param loader the loader
* @returns #TRUE if the loader is hosed.
*/
dbus_bool_t
_dbus_message_loader_get_is_corrupted (DBusMessageLoader *loader)
{
_dbus_assert ((loader->corrupted && loader->corruption_reason != DBUS_VALID) ||
(!loader->corrupted && loader->corruption_reason == DBUS_VALID));
return loader->corrupted;
}
/**
* Sets the maximum size message we allow.
*
* @param loader the loader
* @param size the max message size in bytes
*/
void
_dbus_message_loader_set_max_message_size (DBusMessageLoader *loader,
long size)
{
if (size > DBUS_MAXIMUM_MESSAGE_LENGTH)
{
_dbus_verbose ("clamping requested max message size %ld to %d\n",
size, DBUS_MAXIMUM_MESSAGE_LENGTH);
size = DBUS_MAXIMUM_MESSAGE_LENGTH;
}
loader->max_message_size = size;
}
/**
* Gets the maximum allowed message size in bytes.
*
* @param loader the loader
* @returns max size in bytes
*/
long
_dbus_message_loader_get_max_message_size (DBusMessageLoader *loader)
{
return loader->max_message_size;
}
static DBusDataSlotAllocator slot_allocator;
_DBUS_DEFINE_GLOBAL_LOCK (message_slots);
/**
* Allocates an integer ID to be used for storing application-specific
* data on any DBusMessage. The allocated ID may then be used
* with dbus_message_set_data() and dbus_message_get_data().
* The passed-in slot must be initialized to -1, and is filled in
* with the slot ID. If the passed-in slot is not -1, it's assumed
* to be already allocated, and its refcount is incremented.
*
* The allocated slot is global, i.e. all DBusMessage objects will
* have a slot with the given integer ID reserved.
*
* @param slot_p address of a global variable storing the slot
* @returns #FALSE on failure (no memory)
*/
dbus_bool_t
dbus_message_allocate_data_slot (dbus_int32_t *slot_p)
{
return _dbus_data_slot_allocator_alloc (&slot_allocator,
_DBUS_LOCK_NAME (message_slots),
slot_p);
}
/**
* Deallocates a global ID for message data slots.
* dbus_message_get_data() and dbus_message_set_data() may no
* longer be used with this slot. Existing data stored on existing
* DBusMessage objects will be freed when the message is
* finalized, but may not be retrieved (and may only be replaced if
* someone else reallocates the slot). When the refcount on the
* passed-in slot reaches 0, it is set to -1.
*
* @param slot_p address storing the slot to deallocate
*/
void
dbus_message_free_data_slot (dbus_int32_t *slot_p)
{
_dbus_return_if_fail (*slot_p >= 0);
_dbus_data_slot_allocator_free (&slot_allocator, slot_p);
}
/**
* Stores a pointer on a DBusMessage, along
* with an optional function to be used for freeing
* the data when the data is set again, or when
* the message is finalized. The slot number
* must have been allocated with dbus_message_allocate_data_slot().
*
* @param message the message
* @param slot the slot number
* @param data the data to store
* @param free_data_func finalizer function for the data
* @returns #TRUE if there was enough memory to store the data
*/
dbus_bool_t
dbus_message_set_data (DBusMessage *message,
dbus_int32_t slot,
void *data,
DBusFreeFunction free_data_func)
{
DBusFreeFunction old_free_func;
void *old_data;
dbus_bool_t retval;
_dbus_return_val_if_fail (message != NULL, FALSE);
_dbus_return_val_if_fail (slot >= 0, FALSE);
retval = _dbus_data_slot_list_set (&slot_allocator,
&message->slot_list,
slot, data, free_data_func,
&old_free_func, &old_data);
if (retval)
{
/* Do the actual free outside the message lock */
if (old_free_func)
(* old_free_func) (old_data);
}
return retval;
}
/**
* Retrieves data previously set with dbus_message_set_data().
* The slot must still be allocated (must not have been freed).
*
* @param message the message
* @param slot the slot to get data from
* @returns the data, or #NULL if not found
*/
void*
dbus_message_get_data (DBusMessage *message,
dbus_int32_t slot)
{
void *res;
_dbus_return_val_if_fail (message != NULL, NULL);
res = _dbus_data_slot_list_get (&slot_allocator,
&message->slot_list,
slot);
return res;
}
/**
* Utility function to convert a machine-readable (not translated)
* string into a D-BUS message type.
*
* @code
* "method_call" -> DBUS_MESSAGE_TYPE_METHOD_CALL
* "method_return" -> DBUS_MESSAGE_TYPE_METHOD_RETURN
* "signal" -> DBUS_MESSAGE_TYPE_SIGNAL
* "error" -> DBUS_MESSAGE_TYPE_ERROR
* anything else -> DBUS_MESSAGE_TYPE_INVALID
* @endcode
*
*/
int
dbus_message_type_from_string (const char *type_str)
{
if (strcmp (type_str, "method_call") == 0)
return DBUS_MESSAGE_TYPE_METHOD_CALL;
if (strcmp (type_str, "method_return") == 0)
return DBUS_MESSAGE_TYPE_METHOD_RETURN;
else if (strcmp (type_str, "signal") == 0)
return DBUS_MESSAGE_TYPE_SIGNAL;
else if (strcmp (type_str, "error") == 0)
return DBUS_MESSAGE_TYPE_ERROR;
else
return DBUS_MESSAGE_TYPE_INVALID;
}
/**
* Utility function to convert a D-BUS message type into a
* machine-readable string (not translated).
*
* @code
* DBUS_MESSAGE_TYPE_METHOD_CALL -> "method_call"
* DBUS_MESSAGE_TYPE_METHOD_RETURN -> "method_return"
* DBUS_MESSAGE_TYPE_SIGNAL -> "signal"
* DBUS_MESSAGE_TYPE_ERROR -> "error"
* DBUS_MESSAGE_TYPE_INVALID -> "invalid"
* @endcode
*
*/
const char *
dbus_message_type_to_string (int type)
{
switch (type)
{
case DBUS_MESSAGE_TYPE_METHOD_CALL:
return "method_call";
case DBUS_MESSAGE_TYPE_METHOD_RETURN:
return "method_return";
case DBUS_MESSAGE_TYPE_SIGNAL:
return "signal";
case DBUS_MESSAGE_TYPE_ERROR:
return "error";
default:
return "invalid";
}
}
/** @} */
/* tests in dbus-message-util.c */
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