# -*- python -*-
'''
MIT/X Consortium License
Copyright © 2015 Mattias Andrée <maandree@member.fsf.org>
Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and associated documentation files (the "Software"),
to deal in the Software without restriction, including without limitation
the rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.
'''
cimport cython
from libc.stdlib cimport malloc, free
from posix.types cimport uid_t, gid_t, mode_t
cdef extern int bus_create(const char *, int, char **)
'''
Create a new bus
@param file The pathname of the bus, `NULL` to create a random one
@param flags `BUS_EXCL` (if `file` is not `NULL`) to fail if the file
already exists, otherwise if the file exists, nothing
will happen;
`BUS_INTR` to fail if interrupted
@param out_file Output parameter for the pathname of the bus
@return 0 on success, -1 on error
'''
cdef extern int bus_unlink(const char *)
'''
Remove a bus
@param file The pathname of the bus
@return 0 on success, -1 on error
'''
cdef extern int bus_open(long, const char *, int)
'''
Open an existing bus
@param bus Bus information to fill
@param file The filename of the bus
@param flags `BUS_RDONLY`, `BUS_WRONLY` or `BUS_RDWR`,
the value must not be negative
@return 0 on success, -1 on error
'''
cdef extern int bus_close(long)
'''
Close a bus
@param bus Bus information
@return 0 on success, -1 on error
'''
cdef extern int bus_write(long, const char *, int)
'''
Broadcast a message a bus
@param bus Bus information
@param message The message to write, may not be longer than
`BUS_MEMORY_SIZE` including the NUL-termination
@param flags `BUS_NOWAIT` fail if other process is attempting
to write
@return 0 on success, -1 on error
'''
cdef extern int bus_read(long, int (*)(const char *, void *), void *)
'''
Listen (in a loop, forever) for new message on a bus
@param bus Bus information
@param callback Function to call when a message is received, the
input parameters will be the read message and
`user_data` from `bus_read`'s parameter with the
same name. The message must have been parsed or
copied when `callback` returns as it may be over
overridden after that time. `callback` should
return either of the the values:
0: stop listening
1: continue listening
-1: an error has occurred
@return 0 on success, -1 on error
'''
cdef extern int bus_poll_start(long, int)
'''
Announce that the thread is listening on the bus.
This is required so the will does not miss any
messages due to race conditions. Additionally,
not calling this function will cause the bus the
misbehave, is `bus_poll` is written to expect
this function to have been called.
@param bus Bus information
@param flags `BUS_NOWAIT` if the bus should fail and set `errno` to
`EAGAIN` if there isn't already a message available on
the bus when `bus_poll` is called
@return 0 on success, -1 on error
'''
cdef extern int bus_poll_stop(long)
'''
Announce that the thread has stopped listening on the bus.
This is required so that the thread does not cause others
to wait indefinitely.
@param bus Bus information
@return 0 on success, -1 on error
'''
cdef extern const char *bus_poll(long)
'''
Wait for a message to be broadcasted on the bus.
The caller should make a copy of the received message,
without freeing the original copy, and parse it in a
separate thread. When the new thread has started be
started, the caller of this function should then
either call `bus_poll` again or `bus_poll_stop`.
@param bus Bus information
@return The received message, `NULL` on error
'''
cdef extern int bus_chown(const char *, uid_t, gid_t)
'''
Change the ownership of a bus
`stat(2)` can be used of the bus's associated file to get the bus's ownership
@param file The pathname of the bus
@param owner The user ID of the bus's new owner
@param group The group ID of the bus's new group
@return 0 on success, -1 on error
'''
cdef extern int bus_chmod(const char *, mode_t)
'''
Change the permissions for a bus
`stat(2)` can be used of the bus's associated file to get the bus's permissions
@param file The pathname of the bus
@param mode The permissions of the bus, any permission for a user implies
full permissions for that user, except only the owner may
edit the bus's associated file
@return 0 on success, -1 on error
'''
def bus_allocate() -> int:
'''
Allocate memory for a bus
@return The address of the allocated memory
'''
n = 2 * sizeof(long long) + sizeof(int) + sizeof(char *)
return <long>malloc(n)
def bus_deallocate(address : int):
'''
Deallocate memory for a bus
@param address The address of the allocated memory
'''
free(<void *><long>address)
def bus_create_wrapped(file : str, flags : int) -> str:
'''
Create a new bus
@param file The pathname of the bus, `None` to create a random one
@param flags `BUS_EXCL` (if `file` is not `None`) to fail if the file
already exists, otherwise if the file exists, nothing
will happen;
`BUS_INTR` to fail if interrupted
@return The pathname of the bus, `None` on error;
`file` is returned unless `file` is `None`
'''
cdef const char* cfile
cdef char* ofile
cdef bytes bs
if file is not None:
bs = file.encode('utf-8') + bytes([0])
cfile = bs
r = bus_create(cfile, flags, <char **>NULL)
return file if r == 0 else None
r = bus_create(<char *>NULL, flags, &ofile)
if r == 0:
bs = ofile
return bs.decode('utf-8', 'strict')
return None
def bus_unlink_wrapped(file : str) -> int:
'''
Remove a bus
@param file The pathname of the bus
@return 0 on success, -1 on error
'''
cdef const char* cfile
cdef bytes bs
bs = file.encode('utf-8') + bytes([0])
cfile = bs
return bus_unlink(cfile)
def bus_open_wrapped(bus : int, file : str, flags : int) -> int:
'''
Open an existing bus
@param bus Bus information to fill
@param file The filename of the bus
@param flags `BUS_RDONLY`, `BUS_WRONLY` or `BUS_RDWR`,
the value must not be negative
@return 0 on success, -1 on error
'''
cdef const char* cfile
cdef bytes bs
bs = file.encode('utf-8') + bytes([0])
cfile = bs
return bus_open(<long>bus, cfile, <int>flags)
def bus_close_wrapped(bus : int) -> int:
'''
Close a bus
@param bus Bus information
@return 0 on success, -1 on error
'''
return bus_close(<long>bus)
def bus_write_wrapped(bus : int, message : str, flags : int) -> int:
'''
Broadcast a message a bus
@param bus Bus information
@param message The message to write, may not be longer than
`BUS_MEMORY_SIZE` including the NUL-termination
@param flags `BUS_NOWAIT` fail with errno set to `os.errno.EAGAIN`
if other process is attempting to write
@return 0 on success, -1 on error
'''
cdef const char* cmessage
cdef bytes bs
bs = message.encode('utf-8') + bytes([0])
cmessage = bs
return bus_write(<long>bus, cmessage, <int>flags)
cdef int bus_callback_wrapper(const char *message, user_data):
cdef bytes bs
callback, user_data = tuple(<object>user_data)
if message is NULL:
return <int>callback(None, user_data)
else:
bs = message
return <int>callback(bs, user_data)
def bus_read_wrapped(bus : int, callback : callable, user_data) -> int:
'''
Listen (in a loop, forever) for new message on a bus
@param bus Bus information
@param callback Function to call when a message is received, the
input parameters will be the read message and
`user_data` from `bus_read`'s parameter with the
same name. The message must have been parsed or
copied when `callback` returns as it may be over
overridden after that time. `callback` should
return either of the the values:
0: stop listening
1: continue listening
-1: an error has occurred
@return 0 on success, -1 on error
'''
user = (callback, user_data)
return bus_read(<long>bus, <int (*)(const char *, void *)>&bus_callback_wrapper, <void *>user)
def bus_poll_start_wrapped(bus : int, flags : int) -> int:
'''
Announce that the thread is listening on the bus.
This is required so the will does not miss any
messages due to race conditions. Additionally,
not calling this function will cause the bus the
misbehave, is `bus_poll_wrapped` is written to expect
this function to have been called.
@param bus Bus information
@param flags `BUS_NOWAIT` if the bus should fail and set `errno` to
`os.errno.EAGAIN` if there isn't already a message
available on
the bus when `bus_poll` is called
@return 0 on success, -1 on error
'''
return bus_poll_start(<long>bus, <int>flags)
def bus_poll_stop_wrapped(bus : int) -> int:
'''
Announce that the thread has stopped listening on the bus.
This is required so that the thread does not cause others
to wait indefinitely.
@param bus Bus information
@return 0 on success, -1 on error
'''
return bus_poll_stop(<long>bus)
def bus_poll_wrapped(bus : int) -> bytes:
'''
Wait for a message to be broadcasted on the bus.
The caller should make a copy of the received message,
without freeing the original copy, and parse it in a
separate thread. When the new thread has started be
started, the caller of this function should then
either call `bus_poll_wrapped` again or
`bus_poll_stop_wrapped`.
@param bus Bus information
@return The received message, `None` on error
'''
cdef const char* msg
cdef bytes bs
msg = bus_poll(<long>bus)
if msg is NULL:
return None
bs = msg
return bs
def bus_chown_wrapped(file : str, owner : int, group : int) -> int:
'''
Change the ownership of a bus
`os.stat` can be used of the bus's associated file to get the bus's ownership
@param file The pathname of the bus
@param owner The user ID of the bus's new owner
@param group The group ID of the bus's new group
@return 0 on success, -1 on error
'''
cdef const char* cfile
cdef bytes bs
bs = file.encode('utf-8') + bytes([0])
cfile = bs
return bus_chown(cfile, <uid_t>owner, <gid_t>group)
def bus_chmod_wrapped(file : str, mode : int) -> int:
'''
Change the permissions for a bus
`os.stat` can be used of the bus's associated file to get the bus's permissions
@param file The pathname of the bus
@param mode The permissions of the bus, any permission for a user implies
full permissions for that user, except only the owner may
edit the bus's associated file
@return 0 on success, -1 on error
'''
cdef const char* cfile
cdef bytes bs
bs = file.encode('utf-8') + bytes([0])
cfile = bs
return bus_chmod(cfile, <mode_t>mode)
