2 # A transport class. With two implementations.
3 # One for socket and one for shared memory.
11 typedef void (*vac_callback_t)(unsigned char * data, int len);
12 typedef void (*vac_error_callback_t)(void *, unsigned char *, int);
13 int vac_connect(char * name, char * chroot_prefix, vac_callback_t cb,
15 int vac_disconnect(void);
16 int vac_read(char **data, int *l, unsigned short timeout);
17 int vac_write(char *data, int len);
18 void vac_free(void * msg);
20 int vac_get_msg_index(unsigned char * name);
21 int vac_msg_table_size(void);
22 int vac_msg_table_max_index(void);
24 void vac_rx_suspend (void);
25 void vac_rx_resume (void);
26 void vac_set_error_handler(vac_error_callback_t);
27 void vac_mem_init (size_t size);
32 # Barfs on failure, no need to check success.
33 vpp_api = ffi.dlopen('libvppapiclient.so')
36 @ffi.callback("void(unsigned char *, int)")
37 def vac_callback_sync(data, len):
38 vpp_object.msg_handler_sync(ffi.buffer(data, len))
41 @ffi.callback("void(unsigned char *, int)")
42 def vac_callback_async(data, len):
43 vpp_object.msg_handler_async(ffi.buffer(data, len))
46 @ffi.callback("void(void *, unsigned char *, int)")
47 def vac_error_handler(arg, msg, msg_len):
48 vpp_object.logger.warning("VPP API client:: %s", ffi.string(msg, msg_len))
51 class VppTransportShmemIOError(IOError):
52 """ exception communicating with vpp over shared memory """
54 def __init__(self, rv, descr):
58 super(VppTransportShmemIOError, self).__init__(rv, descr)
61 class VppTransport(object):
62 VppTransportShmemIOError = VppTransportShmemIOError
64 def __init__(self, parent, read_timeout, server_address):
65 self.connected = False
66 self.read_timeout = read_timeout
71 vpp_api.vac_mem_init(0)
73 # Register error handler
74 vpp_api.vac_set_error_handler(vac_error_handler)
77 # from_buffer supported from 1.8.0
78 (major, minor, patch) = [int(s) for s in
79 cffi.__version__.split('.', 3)]
80 if major >= 1 and minor >= 8:
81 self.write = self._write_new_cffi
83 self.write = self._write_legacy_cffi
85 def connect(self, name, pfx, msg_handler, rx_qlen):
89 return vpp_api.vac_connect(name.encode('ascii'), pfx, msg_handler, rx_qlen)
92 self.connected = False
93 return vpp_api.vac_disconnect()
96 vpp_api.vac_rx_suspend()
99 vpp_api.vac_rx_resume()
101 def get_callback(self, do_async):
102 return vac_callback_sync if not do_async else vac_callback_async
104 def get_msg_index(self, name):
105 return vpp_api.vac_get_msg_index(name.encode('ascii'))
107 def msg_table_max_index(self):
108 return vpp_api.vac_msg_table_max_index()
110 def _write_new_cffi(self, buf):
111 """Send a binary-packed message to VPP."""
112 if not self.connected:
113 raise VppTransportShmemIOError(1, 'Not connected')
114 return vpp_api.vac_write(ffi.from_buffer(buf), len(buf))
116 def _write_legacy_cffi(self, buf):
117 """Send a binary-packed message to VPP."""
118 if not self.connected:
119 raise VppTransportShmemIOError(1, 'Not connected')
120 return vpp_api.vac_write(bytes(buf), len(buf))
122 def read(self, timeout=None):
123 if not self.connected:
124 raise VppTransportShmemIOError(1, 'Not connected')
126 timeout = self.read_timeout
127 mem = ffi.new("char **")
128 size = ffi.new("int *")
129 rv = vpp_api.vac_read(mem, size, timeout)
131 strerror = 'vac_read failed. It is likely that VPP died.'
132 raise VppTransportShmemIOError(rv, strerror)
133 msg = bytes(ffi.buffer(mem[0], size[0]))
134 vpp_api.vac_free(mem[0])