| /* |
| Copyright (c) 2014 Drew Crawford. All rights reserved. |
| |
| 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. |
| */ |
| |
| /* Base class for device. */ |
| struct nn_device_recipe { |
| |
| /* NN_CHECK flags. */ |
| int required_checks; |
| |
| /* The entry function. This checks the inputs according to the |
| required_checks flag, chooses the polling function, and starts |
| the device. You can override this function to implement |
| additional checks.*/ |
| int(*nn_device_entry) (struct nn_device_recipe *device, |
| int s1, int s2, int flags); |
| |
| /* The two-way poll function. */ |
| int (*nn_device_twoway) (struct nn_device_recipe *device, int s1, int s2); |
| |
| /* The one-way poll function. */ |
| int (*nn_device_oneway) (struct nn_device_recipe *device, int s1, int s2); |
| |
| int (*nn_device_loopback) (struct nn_device_recipe *device, int s); |
| |
| /* The movemsg function. */ |
| int (*nn_device_mvmsg) (struct nn_device_recipe *device, |
| int from, int to, int flags); |
| |
| /* The message intercept function. This function gives you an opportunity |
| to modify or cancel an nn_msghdr as it passes from one socket |
| to the other. |
| |
| from - the socket that the msghdr was received from |
| to - the socket where it is going |
| flags - the flags that are being used for send and receive functions |
| msghdr - the nn_msghdr that was received from the from socket |
| bytes - the actual received length of the msg. |
| The nn_msghdr->msg_iov->iov_len is not valid because |
| it contains NN_MSG |
| |
| return values: |
| |
| 1 indicates that the msghdr should be forwarded. |
| 0 indicates that the msghdr should *not* be forwarded, |
| e.g. the message is dropped in the device |
| -1 indicates an error. Set errno. |
| */ |
| int (*nn_device_rewritemsg) (struct nn_device_recipe *device, |
| int from, int to, int flags, struct nn_msghdr *msghdr, int bytes); |
| }; |
| |
| /* Default implementations of the functions. */ |
| int nn_device_loopback (struct nn_device_recipe *device, int s); |
| int nn_device_twoway (struct nn_device_recipe *device, int s1, int s2); |
| int nn_device_oneway (struct nn_device_recipe *device, int s1, int s2); |
| int nn_device_mvmsg (struct nn_device_recipe *device, |
| int from, int to, int flags); |
| int nn_device_entry(struct nn_device_recipe *device, |
| int s1, int s2, int flags); |
| int nn_device_rewritemsg(struct nn_device_recipe *device, |
| int from, int to, int flags, struct nn_msghdr *msghdr, int bytes); |
| |
| |
| /* At least one socket must be passed to the device. */ |
| #define NN_CHECK_AT_LEAST_ONE_SOCKET (1 << 0) |
| /* Loopback devices are allowed. */ |
| #define NN_CHECK_ALLOW_LOOPBACK (1 << 1) |
| /* Bidirectional devices are allowed. */ |
| #define NN_CHECK_ALLOW_BIDIRECTIONAL (1 << 2) |
| /* Unidirectional devices are allowed. */ |
| #define NN_CHECK_ALLOW_UNIDIRECTIONAL (1<<3) |
| /* Both sockets must be raw. */ |
| #define NN_CHECK_REQUIRE_RAW_SOCKETS (1 << 4) |
| /* Both sockets must be same protocol family. */ |
| #define NN_CHECK_SAME_PROTOCOL_FAMILY (1 << 5) |
| /* Check socket directionality. */ |
| #define NN_CHECK_SOCKET_DIRECTIONALITY (1 << 6) |
| |
| /* Allows spawning a custom device from a recipe */ |
| int nn_custom_device(struct nn_device_recipe *device, |
| int s1, int s2, int flags); |
| |
| static struct nn_device_recipe nn_ordinary_device = { |
| NN_CHECK_AT_LEAST_ONE_SOCKET | NN_CHECK_ALLOW_LOOPBACK | NN_CHECK_ALLOW_BIDIRECTIONAL | NN_CHECK_REQUIRE_RAW_SOCKETS | NN_CHECK_SAME_PROTOCOL_FAMILY | NN_CHECK_SOCKET_DIRECTIONALITY | NN_CHECK_ALLOW_UNIDIRECTIONAL, |
| nn_device_entry, |
| nn_device_twoway, |
| nn_device_oneway, |
| nn_device_loopback, |
| nn_device_mvmsg, |
| nn_device_rewritemsg |
| }; |
| |