diff options
Diffstat (limited to 'src/afb-proto-ws.c')
| -rw-r--r-- | src/afb-proto-ws.c | 1171 |
1 files changed, 1171 insertions, 0 deletions
diff --git a/src/afb-proto-ws.c b/src/afb-proto-ws.c new file mode 100644 index 00000000..1f17cd77 --- /dev/null +++ b/src/afb-proto-ws.c @@ -0,0 +1,1171 @@ +/* + * Copyright (C) 2015, 2016, 2017 "IoT.bzh" + * Author José Bollo <jose.bollo@iot.bzh> + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#define _GNU_SOURCE + +#define NO_PLUGIN_VERBOSE_MACRO + +#include <stdlib.h> +#include <string.h> +#include <assert.h> +#include <fcntl.h> +#include <unistd.h> +#include <errno.h> +#include <endian.h> +#include <netdb.h> +#include <sys/types.h> +#include <sys/socket.h> +#include <sys/un.h> +#include <pthread.h> + +#include <json-c/json.h> +#include <systemd/sd-event.h> + +#include "afb-common.h" + +#include "afb-ws.h" +#include "afb-msg-json.h" +#include "afb-proto-ws.h" +#include "verbose.h" + +struct afb_proto_ws; + +/******** implementation of internal binder protocol per api **************/ +/* + +This protocol is asymetric: there is a client and a server + +The client can require the following actions: + + - call a verb + + - ask for description + +The server must reply to the previous actions by + + - answering success or failure of the call + + - answering the required description + +The server can also within the context of a call + + - make a subcall + + - subscribe or unsubscribe an event + +For the purpose of handling events the server can: + + - create/destroy an event + + - push or brodcast data as an event + +*/ +/************** constants for protocol definition *************************/ + +#define CHAR_FOR_CALL 'C' +#define CHAR_FOR_ANSWER_SUCCESS 'T' +#define CHAR_FOR_ANSWER_FAIL 'F' +#define CHAR_FOR_EVT_BROADCAST '*' +#define CHAR_FOR_EVT_ADD '+' +#define CHAR_FOR_EVT_DEL '-' +#define CHAR_FOR_EVT_PUSH '!' +#define CHAR_FOR_EVT_SUBSCRIBE 'S' +#define CHAR_FOR_EVT_UNSUBSCRIBE 'U' +#define CHAR_FOR_SUBCALL_CALL 'B' +#define CHAR_FOR_SUBCALL_REPLY 'R' +#define CHAR_FOR_DESCRIBE 'D' +#define CHAR_FOR_DESCRIPTION 'd' + +/******************* handling subcalls *****************************/ + +/** + * Structure on server side for recording pending + * subcalls. + */ +struct server_subcall +{ + struct server_subcall *next; /**< next subcall for the client */ + uint32_t subcallid; /**< the subcallid */ + void (*callback)(void*, int, struct json_object*); /**< callback on completion */ + void *closure; /**< closure of the callback */ +}; + +/** + * Structure for sending back replies on client side + */ +struct afb_proto_ws_subcall +{ + struct afb_proto_ws *protows; /**< proto descriptor */ + void *buffer; + uint32_t subcallid; /**< subcallid for the reply */ +}; + +/* + * structure for recording calls on client side + */ +struct client_call { + struct client_call *next; /* the next call */ + struct afb_proto_ws *protows; /* the proto_ws */ + void *request; + uint32_t callid; /* the message identifier */ +}; + +/* + * structure for a ws request + */ +struct afb_proto_ws_call { + struct client_call *next; /* the next call */ + struct afb_proto_ws *protows; /* the client of the request */ + uint32_t refcount; /* reference count */ + uint32_t callid; /* the incoming request callid */ + char *buffer; /* the incoming buffer */ +}; + +/* + * structure for recording describe requests + */ +struct client_describe +{ + struct client_describe *next; + struct afb_proto_ws *protows; + void (*callback)(void*, struct json_object*); + void *closure; + uint32_t descid; +}; + +/* + * structure for jobs of describing + */ +struct afb_proto_ws_describe +{ + struct afb_proto_ws *protows; + uint32_t descid; +}; + +/******************* proto description for client or servers ******************/ + +struct afb_proto_ws +{ + /* count of references */ + int refcount; + + /* file descriptor */ + int fd; + + /* resource control */ + pthread_mutex_t mutex; + + /* websocket */ + struct afb_ws *ws; + + /* the client closure */ + void *closure; + + /* the client side interface */ + const struct afb_proto_ws_client_itf *client_itf; + + /* the server side interface */ + const struct afb_proto_ws_server_itf *server_itf; + + /* emitted calls (client side) */ + struct client_call *calls; + + /* pending subcalls (server side) */ + struct server_subcall *subcalls; + + /* pending description (client side) */ + struct client_describe *describes; + + /* on hangup callback */ + void (*on_hangup)(void *closure); +}; + +/******************* common useful tools **********************************/ + +/** + * translate a pointer to some integer + * @param ptr the pointer to translate + * @return an integer + */ +static inline uint32_t ptr2id(void *ptr) +{ + return (uint32_t)(((intptr_t)ptr) >> 6); +} + +/******************* serialisation part **********************************/ + +struct readbuf +{ + char *base, *head, *end; +}; + +#define WRITEBUF_COUNT_MAX 32 +struct writebuf +{ + struct iovec iovec[WRITEBUF_COUNT_MAX]; + uint32_t uints[WRITEBUF_COUNT_MAX]; + int count; +}; + +static char *readbuf_get(struct readbuf *rb, uint32_t length) +{ + char *before = rb->head; + char *after = before + length; + if (after > rb->end) + return 0; + rb->head = after; + return before; +} + +static int readbuf_char(struct readbuf *rb, char *value) +{ + if (rb->head >= rb->end) + return 0; + *value = *rb->head++; + return 1; +} + +static int readbuf_uint32(struct readbuf *rb, uint32_t *value) +{ + char *after = rb->head + sizeof *value; + if (after > rb->end) + return 0; + memcpy(value, rb->head, sizeof *value); + rb->head = after; + *value = le32toh(*value); + return 1; +} + +static int readbuf_string(struct readbuf *rb, const char **value, size_t *length) +{ + uint32_t len; + if (!readbuf_uint32(rb, &len) || !len) + return 0; + if (length) + *length = (size_t)(len - 1); + return (*value = readbuf_get(rb, len)) != NULL && rb->head[-1] == 0; +} + +static int readbuf_object(struct readbuf *rb, struct json_object **object) +{ + const char *string; + struct json_object *o; + int rc = readbuf_string(rb, &string, NULL); + if (rc) { + o = json_tokener_parse(string); + if (o == NULL && strcmp(string, "null")) + o = json_object_new_string(string); + *object = o; + } + return rc; +} + +static int writebuf_put(struct writebuf *wb, const void *value, size_t length) +{ + int i = wb->count; + if (i == WRITEBUF_COUNT_MAX) + return 0; + wb->iovec[i].iov_base = (void*)value; + wb->iovec[i].iov_len = length; + wb->count = i + 1; + return 1; +} + +static int writebuf_char(struct writebuf *wb, char value) +{ + int i = wb->count; + if (i == WRITEBUF_COUNT_MAX) + return 0; + *(char*)&wb->uints[i] = value; + wb->iovec[i].iov_base = &wb->uints[i]; + wb->iovec[i].iov_len = 1; + wb->count = i + 1; + return 1; +} + +static int writebuf_uint32(struct writebuf *wb, uint32_t value) +{ + int i = wb->count; + if (i == WRITEBUF_COUNT_MAX) + return 0; + wb->uints[i] = htole32(value); + wb->iovec[i].iov_base = &wb->uints[i]; + wb->iovec[i].iov_len = sizeof wb->uints[i]; + wb->count = i + 1; + return 1; +} + +static int writebuf_string_length(struct writebuf *wb, const char *value, size_t length) +{ + uint32_t len = (uint32_t)++length; + return (size_t)len == length && len && writebuf_uint32(wb, len) && writebuf_put(wb, value, length); +} + +static int writebuf_string(struct writebuf *wb, const char *value) +{ + return writebuf_string_length(wb, value, strlen(value)); +} + +static int writebuf_object(struct writebuf *wb, struct json_object *object) +{ + const char *string = json_object_to_json_string_ext(object, JSON_C_TO_STRING_PLAIN); + return string != NULL && writebuf_string(wb, string); +} + +/******************* ws request part for server *****************/ + +void afb_proto_ws_call_addref(struct afb_proto_ws_call *call) +{ + __atomic_add_fetch(&call->refcount, 1, __ATOMIC_RELAXED); +} + +void afb_proto_ws_call_unref(struct afb_proto_ws_call *call) +{ + if (__atomic_sub_fetch(&call->refcount, 1, __ATOMIC_RELAXED)) + return; + + afb_proto_ws_unref(call->protows); + free(call->buffer); + free(call); +} + +int afb_proto_ws_call_success(struct afb_proto_ws_call *call, struct json_object *obj, const char *info) +{ + int rc = -1; + struct writebuf wb = { .count = 0 }; + + if (writebuf_char(&wb, CHAR_FOR_ANSWER_SUCCESS) + && writebuf_uint32(&wb, call->callid) + && writebuf_string(&wb, info ?: "") + && writebuf_object(&wb, obj)) { + rc = afb_ws_binary_v(call->protows->ws, wb.iovec, wb.count); + if (rc >= 0) { + rc = 0; + goto success; + } + } + ERROR("error while sending success"); +success: + return rc; +} + +int afb_proto_ws_call_fail(struct afb_proto_ws_call *call, const char *status, const char *info) +{ + int rc = -1; + struct writebuf wb = { .count = 0 }; + + if (writebuf_char(&wb, CHAR_FOR_ANSWER_FAIL) + && writebuf_uint32(&wb, call->callid) + && writebuf_string(&wb, status) + && writebuf_string(&wb, info ? : "")) { + rc = afb_ws_binary_v(call->protows->ws, wb.iovec, wb.count); + if (rc >= 0) { + rc = 0; + goto success; + } + } + ERROR("error while sending fail"); +success: + return rc; +} + +int afb_proto_ws_call_subcall(struct afb_proto_ws_call *call, const char *api, const char *verb, struct json_object *args, void (*callback)(void*, int, struct json_object*), void *cb_closure) +{ + int rc = -1; + struct writebuf wb = { .count = 0 }; + struct server_subcall *sc, *osc; + struct afb_proto_ws *protows = call->protows; + + sc = malloc(sizeof *sc); + if (!sc) + errno = ENOMEM; + else { + sc->callback = callback; + sc->closure = cb_closure; + + pthread_mutex_unlock(&protows->mutex); + sc->subcallid = ptr2id(sc); + do { + sc->subcallid++; + osc = protows->subcalls; + while(osc && osc->subcallid != sc->subcallid) + osc = osc->next; + } while (osc); + sc->next = protows->subcalls; + protows->subcalls = sc; + pthread_mutex_unlock(&protows->mutex); + + if (writebuf_char(&wb, CHAR_FOR_SUBCALL_CALL) + && writebuf_uint32(&wb, sc->subcallid) + && writebuf_uint32(&wb, call->callid) + && writebuf_string(&wb, api) + && writebuf_string(&wb, verb) + && writebuf_object(&wb, args)) { + rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count); + if (rc >= 0) { + rc = 0; + goto success; + } + } + } + ERROR("error while sending subcall"); +success: + return rc; +} + +int afb_proto_ws_call_subscribe(struct afb_proto_ws_call *call, const char *event_name, int event_id) +{ + int rc = -1; + struct writebuf wb = { .count = 0 }; + + if (writebuf_char(&wb, CHAR_FOR_EVT_SUBSCRIBE) + && writebuf_uint32(&wb, call->callid) + && writebuf_uint32(&wb, (uint32_t)event_id) + && writebuf_string(&wb, event_name)) { + rc = afb_ws_binary_v(call->protows->ws, wb.iovec, wb.count); + if (rc >= 0) { + rc = 0; + goto success; + } + } + ERROR("error while subscribing event"); +success: + return rc; +} + +int afb_proto_ws_call_unsubscribe(struct afb_proto_ws_call *call, const char *event_name, int event_id) +{ + int rc = -1; + struct writebuf wb = { .count = 0 }; + + if (writebuf_char(&wb, CHAR_FOR_EVT_UNSUBSCRIBE) + && writebuf_uint32(&wb, call->callid) + && writebuf_uint32(&wb, (uint32_t)event_id) + && writebuf_string(&wb, event_name)) { + rc = afb_ws_binary_v(call->protows->ws, wb.iovec, wb.count); + if (rc >= 0) { + rc = 0; + goto success; + } + } + ERROR("error while subscribing event"); +success: + return rc; +} + +/******************* client part **********************************/ + +/* search a memorized call */ +static struct client_call *client_call_search(struct afb_proto_ws *protows, uint32_t callid) +{ + struct client_call *call; + + call = protows->calls; + while (call != NULL && call->callid != callid) + call = call->next; + + return call; +} + +/* free and release the memorizing call */ +static void client_call_destroy(struct client_call *call) +{ + struct client_call **prv; + + prv = &call->protows->calls; + while (*prv != NULL) { + if (*prv == call) { + *prv = call->next; + break; + } + prv = &(*prv)->next; + } + free(call); +} + +/* get event data from the message */ +static int client_msg_event_read(struct readbuf *rb, uint32_t *eventid, const char **name) +{ + return readbuf_uint32(rb, eventid) && readbuf_string(rb, name, NULL); +} + +/* get event from the message */ +static int client_msg_call_get(struct afb_proto_ws *protows, struct readbuf *rb, struct client_call **call) +{ + uint32_t callid; + + /* get event data from the message */ + if (!readbuf_uint32(rb, &callid)) { + ERROR("Invalid message"); + return 0; + } + + /* get the call */ + *call = client_call_search(protows, callid); + if (*call == NULL) { + ERROR("message not found"); + return 0; + } + + return 1; +} + +/* adds an event */ +static void client_on_event_create(struct afb_proto_ws *protows, struct readbuf *rb) +{ + const char *event_name; + uint32_t event_id; + + if (protows->client_itf->on_event_create && client_msg_event_read(rb, &event_id, &event_name)) + protows->client_itf->on_event_create(protows->closure, event_name, (int)event_id); +} + +/* removes an event */ +static void client_on_event_remove(struct afb_proto_ws *protows, struct readbuf *rb) +{ + const char *event_name; + uint32_t event_id; + + if (protows->client_itf->on_event_remove && client_msg_event_read(rb, &event_id, &event_name)) + protows->client_itf->on_event_remove(protows->closure, event_name, (int)event_id); +} + +/* subscribes an event */ +static void client_on_event_subscribe(struct afb_proto_ws *protows, struct readbuf *rb) +{ + const char *event_name; + uint32_t event_id; + struct client_call *call; + + if (protows->client_itf->on_event_subscribe && client_msg_call_get(protows, rb, &call) && client_msg_event_read(rb, &event_id, &event_name)) + protows->client_itf->on_event_subscribe(protows->closure, call->request, event_name, (int)event_id); +} + +/* unsubscribes an event */ +static void client_on_event_unsubscribe(struct afb_proto_ws *protows, struct readbuf *rb) +{ + const char *event_name; + uint32_t event_id; + struct client_call *call; + + if (protows->client_itf->on_event_unsubscribe && client_msg_call_get(protows, rb, &call) && client_msg_event_read(rb, &event_id, &event_name)) + protows->client_itf->on_event_unsubscribe(protows->closure, call->request, event_name, (int)event_id); +} + +/* receives broadcasted events */ +static void client_on_event_broadcast(struct afb_proto_ws *protows, struct readbuf *rb) +{ + const char *event_name; + struct json_object *object; + + if (protows->client_itf->on_event_broadcast && readbuf_string(rb, &event_name, NULL) && readbuf_object(rb, &object)) + protows->client_itf->on_event_broadcast(protows->closure, event_name, object); +} + +/* pushs an event */ +static void client_on_event_push(struct afb_proto_ws *protows, struct readbuf *rb) +{ + const char *event_name; + uint32_t event_id; + struct json_object *object; + + if (protows->client_itf->on_event_push && client_msg_event_read(rb, &event_id, &event_name) && readbuf_object(rb, &object)) + protows->client_itf->on_event_push(protows->closure, event_name, (int)event_id, object); +} + +static void client_on_reply_success(struct afb_proto_ws *protows, struct readbuf *rb) +{ + struct client_call *call; + struct json_object *object; + const char *info; + + if (!client_msg_call_get(protows, rb, &call)) + return; + + if (readbuf_string(rb, &info, NULL) && readbuf_object(rb, &object)) { + protows->client_itf->on_reply_success(protows->closure, call->request, object, info); + } else { + protows->client_itf->on_reply_fail(protows->closure, call->request, "proto-error", "can't process success"); + } + client_call_destroy(call); +} + +static void client_on_reply_fail(struct afb_proto_ws *protows, struct readbuf *rb) +{ + struct client_call *call; + const char *info, *status; + + if (!client_msg_call_get(protows, rb, &call)) + return; + + if (readbuf_string(rb, &status, NULL) && readbuf_string(rb, &info, NULL)) { + protows->client_itf->on_reply_fail(protows->closure, call->request, status, info); + } else { + protows->client_itf->on_reply_fail(protows->closure, call->request, "proto-error", "can't process fail"); + } + client_call_destroy(call); +} + +/* send a subcall reply */ +static int client_send_subcall_reply(struct afb_proto_ws *protows, uint32_t subcallid, int status, json_object *object) +{ + struct writebuf wb = { .count = 0 }; + char ie = status < 0; + + return -!(writebuf_char(&wb, CHAR_FOR_SUBCALL_REPLY) + && writebuf_uint32(&wb, subcallid) + && writebuf_char(&wb, ie) + && writebuf_object(&wb, object) + && afb_ws_binary_v(protows->ws, wb.iovec, wb.count) >= 0); +} + +/* callback for subcall reply */ +int afb_proto_ws_subcall_reply(struct afb_proto_ws_subcall *subcall, int status, struct json_object *result) +{ + int rc = client_send_subcall_reply(subcall->protows, subcall->subcallid, status, result); + afb_proto_ws_unref(subcall->protows); + free(subcall->buffer); + free(subcall); + return rc; +} + +/* received a subcall request */ +static void client_on_subcall(struct afb_proto_ws *protows, struct readbuf *rb) +{ + struct afb_proto_ws_subcall *subcall; + struct client_call *call; + const char *api, *verb; + uint32_t subcallid; + struct json_object *object; + + /* get the subcallid */ + if (!readbuf_uint32(rb, &subcallid)) + return; + + /* if not expected drop it */ + if (!protows->client_itf->on_subcall) + goto error; + + /* retrieve the message data */ + if (!client_msg_call_get(protows, rb, &call)) + goto error; + + /* allocation of the subcall */ + subcall = malloc(sizeof *subcall); + if (!subcall) + goto error; + + /* make the call */ + if (readbuf_string(rb, &api, NULL) + && readbuf_string(rb, &verb, NULL) + && readbuf_object(rb, &object)) { + afb_proto_ws_addref(protows); + subcall->protows = protows; + subcall->subcallid = subcallid; + subcall->buffer = rb->base; + rb->base = NULL; + protows->client_itf->on_subcall(protows->closure, subcall, call->request, api, verb, object); + return; + } + free(subcall); +error: + client_send_subcall_reply(protows, subcallid, 1, NULL); +} + +static void client_on_description(struct afb_proto_ws *protows, struct readbuf *rb) +{ + uint32_t descid; + struct client_describe *desc, **prv; + struct json_object *object; + + if (readbuf_uint32(rb, &descid)) { + prv = &protows->describes; + while ((desc = *prv) && desc->descid != descid) + prv = &desc->next; + if (desc) { + *prv = desc->next; + if (!readbuf_object(rb, &object)) + object = NULL; + desc->callback(desc->closure, object); + free(desc); + } + } +} + +/* callback when receiving binary data */ +static void client_on_binary(void *closure, char *data, size_t size) +{ + struct afb_proto_ws *protows; + struct readbuf rb; + + rb.base = data; + if (size > 0) { + rb.head = data; + rb.end = data + size; + protows = closure; + + pthread_mutex_lock(&protows->mutex); + switch (*rb.head++) { + case CHAR_FOR_ANSWER_SUCCESS: /* success */ + client_on_reply_success(protows, &rb); + break; + case CHAR_FOR_ANSWER_FAIL: /* fail */ + client_on_reply_fail(protows, &rb); + break; + case CHAR_FOR_EVT_BROADCAST: /* broadcast */ + client_on_event_broadcast(protows, &rb); + break; + case CHAR_FOR_EVT_ADD: /* creates the event */ + client_on_event_create(protows, &rb); + break; + case CHAR_FOR_EVT_DEL: /* removes the event */ + client_on_event_remove(protows, &rb); + break; + case CHAR_FOR_EVT_PUSH: /* pushs the event */ + client_on_event_push(protows, &rb); + break; + case CHAR_FOR_EVT_SUBSCRIBE: /* subscribe event for a request */ + client_on_event_subscribe(protows, &rb); + break; + case CHAR_FOR_EVT_UNSUBSCRIBE: /* unsubscribe event for a request */ + client_on_event_unsubscribe(protows, &rb); + break; + case CHAR_FOR_SUBCALL_CALL: /* subcall */ + client_on_subcall(protows, &rb); + break; + case CHAR_FOR_DESCRIPTION: /* description */ + client_on_description(protows, &rb); + break; + default: /* unexpected message */ + /* TODO: close the connection */ + break; + } + pthread_mutex_unlock(&protows->mutex); + } + free(rb.base); +} + +int afb_proto_ws_client_call( + struct afb_proto_ws *protows, + const char *verb, + struct json_object *args, + const char *sessionid, + void *request +) +{ + int rc = -1; + struct client_call *call; + struct writebuf wb = { .count = 0 }; + + /* allocate call data */ + call = malloc(sizeof *call); + if (call == NULL) { + errno = ENOMEM; + return -1; + } + call->request = request; + + /* init call data */ + pthread_mutex_lock(&protows->mutex); + call->callid = ptr2id(call); + while(client_call_search(protows, call->callid) != NULL) + call->callid++; + call->protows = protows; + call->next = protows->calls; + protows->calls = call; + + /* creates the call message */ + if (!writebuf_char(&wb, CHAR_FOR_CALL) + || !writebuf_uint32(&wb, call->callid) + || !writebuf_string(&wb, verb) + || !writebuf_string(&wb, sessionid) + || !writebuf_object(&wb, args)) { + errno = EINVAL; + goto clean; + } + + /* send */ + rc = afb_ws_binary_v(protows->ws, wb.iovec, wb.count); + if (rc >= 0) { + rc = 0; + goto end; + } + +clean: + client_call_destroy(call); +end: + pthread_mutex_unlock(&protows->mutex); + return rc; +} + +/* get the description */ +int afb_proto_ws_client_describe(struct afb_proto_ws *protows, void (*callback)(void*, struct json_object*), void *closure) +{ + struct client_describe *desc, *d; + struct writebuf wb = { .count = 0 }; + + desc = malloc(sizeof *desc); + if (!desc) { + errno = ENOMEM; + goto error; + } + + /* fill in stack the description of the task */ + pthread_mutex_lock(&protows->mutex); + desc->descid = ptr2id(desc); + d = protows->describes; + while (d) { + if (d->descid != desc->descid) + d = d->next; + else { + desc->descid++; + d = protows->describes; + } + } + desc->callback = callback; + desc->closure = closure; + desc->protows = protows; + desc->next = protows->describes; + protows->describes = desc; + pthread_mutex_unlock(&protows->mutex); + + /* send */ + if (writebuf_char(&wb, CHAR_FOR_DESCRIBE) + && writebuf_uint32(&wb, desc->descid) + && afb_ws_binary_v(protows->ws, wb.iovec, wb.count) >= 0) + return 0; + + pthread_mutex_lock(&protows->mutex); + d = protows->describes; + if (d == desc) + protows->describes = desc->next; + else { + while(d && d->next != desc) + d = d->next; + if (d) + d->next = desc->next; + } + free(desc); + pthread_mutex_unlock(&protows->mutex); +error: + /* TODO? callback(closure, NULL); */ + return -1; +} + +/******************* client description part for server *****************************/ + +/* on call, propagate it to the ws service */ +static void server_on_call(struct afb_proto_ws *protows, struct readbuf *rb) +{ + struct afb_proto_ws_call *call; + const char *uuid, *verb; + uint32_t callid; + size_t lenverb; + struct json_object *object; + + afb_proto_ws_addref(protows); + + /* reads the call message data */ + if (!readbuf_uint32(rb, &callid) + || !readbuf_string(rb, &verb, &lenverb) + || !readbuf_string(rb, &uuid, NULL) + || !readbuf_object(rb, &object)) + goto overflow; + + /* create the request */ + call = malloc(sizeof *call); + if (call == NULL) + goto out_of_memory; + + call->protows = protows; + call->callid = callid; + call->refcount = 1; + call->buffer = rb->base; + rb->base = NULL; /* don't free the buffer */ + + protows->server_itf->on_call(protows->closure, call, verb, object, uuid); + return; + +out_of_memory: + json_object_put(object); + +overflow: + afb_proto_ws_unref(protows); +} + +/* on subcall reply */ +static void server_on_subcall_reply(struct afb_proto_ws *protows, struct readbuf *rb) +{ + char ie; + uint32_t subcallid; + struct json_object *object; + struct server_subcall *sc, **psc; + + /* reads the call message data */ + if (!readbuf_uint32(rb, &subcallid) + || !readbuf_char(rb, &ie) + || !readbuf_object(rb, &object)) { + /* TODO bad protocol */ + return; + } + + /* search the subcall and unlink it */ + pthread_mutex_lock(&protows->mutex); + psc = &protows->subcalls; + while ((sc = *psc) && sc->subcallid != subcallid) + psc = &sc->next; + if (!sc) { + pthread_mutex_unlock(&protows->mutex); + json_object_put(object); + /* TODO subcall not found */ + } else { + *psc = sc->next; + pthread_mutex_unlock(&protows->mutex); + sc->callback(sc->closure, -(int)ie, object); + free(sc); + } +} + +static int server_send_description(struct afb_proto_ws *protows, uint32_t descid, struct json_object *descobj) +{ + struct writebuf wb = { .count = 0 }; + + return -!(writebuf_char(&wb, CHAR_FOR_DESCRIPTION) + && writebuf_uint32(&wb, descid) + && writebuf_object(&wb, descobj) + && afb_ws_binary_v(protows->ws, wb.iovec, wb.count) >= 0); +} + +int afb_proto_ws_describe_put(struct afb_proto_ws_describe *describe, struct json_object *description) +{ + int rc = server_send_description(describe->protows, describe->descid, description); + afb_proto_ws_addref(describe->protows); + free(describe); + return rc; +} + +/* on describe, propagate it to the ws service */ +static void server_on_describe(struct afb_proto_ws *protows, struct readbuf *rb) +{ + uint32_t descid; + struct afb_proto_ws_describe *desc; + + /* reads the descid */ + if (readbuf_uint32(rb, &descid)) { + if (protows->server_itf->on_describe) { + /* create asynchronous job */ + desc = malloc(sizeof *desc); + if (desc) { + desc->descid = descid; + desc->protows = protows; + afb_proto_ws_addref(protows); + protows->server_itf->on_describe(protows->closure, desc); + return; + } + } + server_send_description(protows, descid, NULL); + } +} + +/* callback when receiving binary data */ +static void server_on_binary(void *closure, char *data, size_t size) +{ + struct afb_proto_ws *protows; + struct readbuf rb; + + rb.base = data; + if (size > 0) { + rb.head = data; + rb.end = data + size; + protows = closure; + + switch (*rb.head++) { + case CHAR_FOR_CALL: + server_on_call(protows, &rb); + break; + case CHAR_FOR_SUBCALL_REPLY: + server_on_subcall_reply(protows, &rb); + break; + case CHAR_FOR_DESCRIBE: + server_on_describe(protows, &rb); + break; + default: /* unexpected message */ + /* TODO: close the connection */ + break; + } + } + free(rb.base); +} + +/******************* server part: manage events **********************************/ + +static int server_event_send(struct afb_proto_ws *protows, char order, const char *event_name, int event_id, struct json_object *data) +{ + struct writebuf wb = { .count = 0 }; + + return -!(writebuf_char(&wb, order) + && (order == CHAR_FOR_EVT_BROADCAST || writebuf_uint32(&wb, event_id)) + && writebuf_string(&wb, event_name) + && (order == CHAR_FOR_EVT_ADD || order == CHAR_FOR_EVT_DEL || writebuf_object(&wb, data)) + && afb_ws_binary_v(protows->ws, wb.iovec, wb.count) >= 0); +} + +int afb_proto_ws_server_event_create(struct afb_proto_ws *protows, const char *event_name, int event_id) +{ + return server_event_send(protows, CHAR_FOR_EVT_ADD, event_name, event_id, NULL); +} + +int afb_proto_ws_server_event_remove(struct afb_proto_ws *protows, const char *event_name, int event_id) +{ + return server_event_send(protows, CHAR_FOR_EVT_DEL, event_name, event_id, NULL); +} + +int afb_proto_ws_server_event_push(struct afb_proto_ws *protows, const char *event_name, int event_id, struct json_object *data) +{ + return server_event_send(protows, CHAR_FOR_EVT_PUSH, event_name, event_id, data); +} + +int afb_proto_ws_server_event_broadcast(struct afb_proto_ws *protows, const char *event_name, struct json_object *data) +{ + return server_event_send(protows, CHAR_FOR_EVT_BROADCAST, event_name, 0, data); +} + +/*****************************************************/ + +/* callback when receiving a hangup */ +static void on_hangup(void *closure) +{ + struct afb_proto_ws *protows = closure; + struct server_subcall *sc, *nsc; + struct client_describe *cd, *ncd; + + nsc = protows->subcalls; + while (nsc) { + sc= nsc; + nsc = sc->next; + sc->callback(sc->closure, 1, NULL); + free(sc); + } + + ncd = protows->describes; + while (ncd) { + cd= ncd; + ncd = cd->next; + cd->callback(cd->closure, NULL); + free(cd); + } + + if (protows->fd >= 0) { + protows->fd = -1; + if (protows->on_hangup) + protows->on_hangup(protows->closure); + } +} + +/*****************************************************/ + +static const struct afb_ws_itf proto_ws_client_ws_itf = +{ + .on_close = NULL, + .on_text = NULL, + .on_binary = client_on_binary, + .on_error = NULL, + .on_hangup = on_hangup +}; + +static const struct afb_ws_itf server_ws_itf = +{ + .on_close = NULL, + .on_text = NULL, + .on_binary = server_on_binary, + .on_error = NULL, + .on_hangup = on_hangup +}; + +/*****************************************************/ + +static struct afb_proto_ws *afb_proto_ws_create(int fd, const struct afb_proto_ws_server_itf *itfs, const struct afb_proto_ws_client_itf *itfc, void *closure, const struct afb_ws_itf *itf) +{ + struct afb_proto_ws *protows; + + protows = calloc(1, sizeof *protows); + if (protows == NULL) + errno = ENOMEM; + else { + fcntl(fd, F_SETFD, FD_CLOEXEC); + fcntl(fd, F_SETFL, O_NONBLOCK); + protows->ws = afb_ws_create(afb_common_get_event_loop(), fd, itf, protows); + if (protows->ws != NULL) { + protows->fd = fd; + protows->refcount = 1; + protows->subcalls = NULL; + protows->closure = closure; + protows->server_itf = itfs; + protows->client_itf = itfc; + pthread_mutex_init(&protows->mutex, NULL); + return protows; + } + free(protows); + } + return NULL; +} + +struct afb_proto_ws *afb_proto_ws_create_client(int fd, const struct afb_proto_ws_client_itf *itf, void *closure) +{ + return afb_proto_ws_create(fd, NULL, itf, closure, &proto_ws_client_ws_itf); +} + +struct afb_proto_ws *afb_proto_ws_create_server(int fd, const struct afb_proto_ws_server_itf *itf, void *closure) +{ + return afb_proto_ws_create(fd, itf, NULL, closure, &server_ws_itf); +} + +void afb_proto_ws_unref(struct afb_proto_ws *protows) +{ + if (!__atomic_sub_fetch(&protows->refcount, 1, __ATOMIC_RELAXED)) { + afb_proto_ws_hangup(protows); + afb_ws_destroy(protows->ws); + pthread_mutex_destroy(&protows->mutex); + free(protows); + } +} + +void afb_proto_ws_addref(struct afb_proto_ws *protows) +{ + __atomic_add_fetch(&protows->refcount, 1, __ATOMIC_RELAXED); +} + +int afb_proto_ws_is_client(struct afb_proto_ws *protows) +{ + return !!protows->client_itf; +} + +int afb_proto_ws_is_server(struct afb_proto_ws *protows) +{ + return !!protows->server_itf; +} + +void afb_proto_ws_hangup(struct afb_proto_ws *protows) +{ + afb_ws_hangup(protows->ws); +} + +void afb_proto_ws_on_hangup(struct afb_proto_ws *protows, void (*on_hangup)(void *closure)) +{ + protows->on_hangup = on_hangup; +} + |