return the errno value that was set by the native bus functions, python clears errno3.0

Signed-off-by: Mattias Andrée <maandree@operamail.com>

1 files changed, 118 insertions, 82 deletions

diff --git a/src/native_bus.pyx b/src/native_bus.pyx
index 75bb92a..7dd0601 100644
--- a/src/native_bus.pyx
+++ b/src/native_bus.pyx
@@ -26,6 +26,7 @@ DEALINGS IN THE SOFTWARE.
 cimport cython
 
 from libc.stdlib cimport malloc, free
+from libc.errno cimport errno
 from posix.types cimport uid_t, gid_t, mode_t
 
 
@@ -165,36 +166,40 @@ Change the permissions for a bus
 
 
 
-def bus_allocate() -> int:
+def bus_allocate() -> tuple:
     '''
     Allocate memory for a bus
     
-    @return  The address of the allocated memory
+    @return  :int  The address of the allocated memory
+    @return  :int  The value of `errno`
     '''
     n = 2 * sizeof(long long) + sizeof(int) + sizeof(char *)
-    return <long>malloc(n)
+    r = <long>malloc(n)
+    e = errno
+    return (r, e)
 
 
 def bus_deallocate(address : int):
     '''
     Deallocate memory for a bus
     
-    @param  address  The address of the allocated memory
+    @param  address:int  The address of the allocated memory
     '''
     free(<void *><long>address)
 
 
-def bus_create_wrapped(file : str, flags : int) -> str:
+def bus_create_wrapped(file : str, flags : int) -> tuple:
     '''
     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`
+    @param   file:str   The pathname of the bus, `None` to create a random one
+    @param   flags:int  `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  :str       The pathname of the bus, `None` on error;
+                        `file` is returned unless `file` is `None`
+    @return  :int       The value of `errno`
     '''
     cdef const char* cfile
     cdef char* ofile
@@ -203,71 +208,85 @@ def bus_create_wrapped(file : str, flags : int) -> str:
         bs = file.encode('utf-8') + bytes([0])
         cfile = bs
         r = bus_create(cfile, flags, <char **>NULL)
-        return file if r == 0 else None
+        e = errno
+        return (file if r == 0 else None, e)
     r = bus_create(<char *>NULL, flags, &ofile)
+    e = errno
     if r == 0:
         bs = ofile
-        return bs.decode('utf-8', 'strict')
-    return None
+        return (bs.decode('utf-8', 'strict'), e)
+    return (None, e)
 
 
-def bus_unlink_wrapped(file : str) -> int:
+def bus_unlink_wrapped(file : str) -> tuple:
     '''
     Remove a bus
     
-    @param   file  The pathname of the bus
-    @return        0 on success, -1 on error
+    @param   file:str  The pathname of the bus
+    @return  :int      0 on success, -1 on error
+    @return  :int      The value of `errno`
     '''
     cdef const char* cfile
     cdef bytes bs
     bs = file.encode('utf-8') + bytes([0])
     cfile = bs
-    return bus_unlink(cfile)
+    r = bus_unlink(cfile)
+    e = errno
+    return (r, e)
 
 
-def bus_open_wrapped(bus : int, file : str, flags : int) -> int:
+def bus_open_wrapped(bus : int, file : str, flags : int) -> tuple:
     '''
     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
+    @param   bus:int    Bus information to fill
+    @param   file:str   The filename of the bus
+    @param   flags:int  `BUS_RDONLY`, `BUS_WRONLY` or `BUS_RDWR`,
+                        the value must not be negative
+    @return  :int       0 on success, -1 on error
+    @return  :int       The value of `errno`
     '''
     cdef const char* cfile
     cdef bytes bs
     bs = file.encode('utf-8') + bytes([0])
     cfile = bs
-    return bus_open(<long>bus, cfile, <int>flags)
+    r = bus_open(<long>bus, cfile, <int>flags)
+    e = errno
+    return (r, e)
 
 
-def bus_close_wrapped(bus : int) -> int:
+def bus_close_wrapped(bus : int) -> tuple:
     '''
     Close a bus
     
-    @param   bus  Bus information
-    @return       0 on success, -1 on error
+    @param   bus:int  Bus information
+    @return  :int     0 on success, -1 on error
+    @return  :int     The value of `errno`
     '''
-    return bus_close(<long>bus)
+    r = bus_close(<long>bus)
+    e = errno
+    return (r, e)
 
 
-def bus_write_wrapped(bus : int, message : str, flags : int) -> int:
+def bus_write_wrapped(bus : int, message : str, flags : int) -> tuple:
     '''
     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
+    @param   bus:int      Bus information
+    @param   message:str  The message to write, may not be longer than
+                          `BUS_MEMORY_SIZE` including the NUL-termination
+    @param   flags:int    `BUS_NOWAIT` fail with errno set to `os.errno.EAGAIN`
+                          if other process is attempting to write
+    @return  :int         0 on success, -1 on error
+    @return  :int         The value of `errno`
     '''
     cdef const char* cmessage
     cdef bytes bs
     bs = message.encode('utf-8') + bytes([0])
     cmessage = bs
-    return bus_write(<long>bus, cmessage, <int>flags)
+    r = bus_write(<long>bus, cmessage, <int>flags)
+    e = errno
+    return (r, e)
 
 
 cdef int bus_callback_wrapper(const char *message, user_data):
@@ -280,28 +299,31 @@ cdef int bus_callback_wrapper(const char *message, user_data):
         return <int>callback(bs, user_data)
 
 
-def bus_read_wrapped(bus : int, callback : callable, user_data) -> int:
+def bus_read_wrapped(bus : int, callback : callable, user_data) -> tuple:
     '''
     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
+    @param   bus:int                   Bus information
+    @param   callback:(str?, ¿V?)→int  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  :int                      0 on success, -1 on error
+    @return  :int                      The value of `errno`
     '''
     user = (callback, user_data)
-    return bus_read(<long>bus, <int (*)(const char *, void *)>&bus_callback_wrapper, <void *>user)
+    r = bus_read(<long>bus, <int (*)(const char *, void *)>&bus_callback_wrapper, <void *>user)
+    e = errno
+    return (r, e)
 
 
-def bus_poll_start_wrapped(bus : int, flags : int) -> int:
+def bus_poll_start_wrapped(bus : int, flags : int) -> tuple:
     '''
     Announce that the thread is listening on the bus.
     This is required so the will does not miss any
@@ -310,29 +332,35 @@ def bus_poll_start_wrapped(bus : int, flags : int) -> int:
     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
+    @param   bus:int    Bus information
+    @param   flags:int  `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  :int       0 on success, -1 on error
+    @return  :int       The value of `errno`
     '''
-    return bus_poll_start(<long>bus, <int>flags)
+    r = bus_poll_start(<long>bus, <int>flags)
+    e = errno
+    return (r, e)
 
 
-def bus_poll_stop_wrapped(bus : int) -> int:
+def bus_poll_stop_wrapped(bus : int) -> tuple:
     '''
     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
+    @param   bus:int  Bus information
+    @return  :int     0 on success, -1 on error
+    @return  :int     The value of `errno`
     '''
-    return bus_poll_stop(<long>bus)
+    r = bus_poll_stop(<long>bus)
+    e = errno
+    return (r, e)
 
 
-def bus_poll_wrapped(bus : int) -> bytes:
+def bus_poll_wrapped(bus : int) -> tuple:
     '''
     Wait for a message to be broadcasted on the bus.
     The caller should make a copy of the received message,
@@ -342,51 +370,59 @@ def bus_poll_wrapped(bus : int) -> bytes:
     either call `bus_poll_wrapped` again or
     `bus_poll_stop_wrapped`.
     
-    @param   bus  Bus information
-    @return       The received message, `None` on error
+    @param   bus::int  Bus information
+    @return  :bytes    The received message, `None` on error
+    @return  :int      The value of `errno`
     '''
     cdef const char* msg
     cdef bytes bs
     msg = bus_poll(<long>bus)
+    e = errno
     if msg is NULL:
-        return None
+        return (None, e)
     bs = msg
-    return bs
+    return (bs, e)
 
 
-def bus_chown_wrapped(file : str, owner : int, group : int) -> int:
+def bus_chown_wrapped(file : str, owner : int, group : int) -> tuple:
     '''
     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
+    @param   file:str   The pathname of the bus
+    @param   owner:int  The user ID of the bus's new owner
+    @param   group:int  The group ID of the bus's new group
+    @return  :int       0 on success, -1 on error
+    @return  :int      The value of `errno`
     '''
     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)
+    r = bus_chown(cfile, <uid_t>owner, <gid_t>group)
+    e = errno
+    return (r, e)
 
 
-def bus_chmod_wrapped(file : str, mode : int) -> int:
+def bus_chmod_wrapped(file : str, mode : int) -> tuple:
     '''
     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
+    @param   file:str  The pathname of the bus
+    @param   mode:int  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  :int      0 on success, -1 on error
+    @return  :int      The value of `errno`
     '''
     cdef const char* cfile
     cdef bytes bs
     bs = file.encode('utf-8') + bytes([0])
     cfile = bs
-    return bus_chmod(cfile, <mode_t>mode)
+    r = bus_chmod(cfile, <mode_t>mode)
+    e = errno
+    return (r, e)