src/afb-subcall.c

   1 /*
   2  * Copyright (C) 2016, 2017 "IoT.bzh"
   3  * Author: José Bollo <jose.bollo@iot.bzh>
   4  *
   5  * Licensed under the Apache License, Version 2.0 (the "License");
   6  * you may not use this file except in compliance with the License.
   7  * You may obtain a copy of the License at
   8  *
   9  *   http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  */
  17
  18 #define _GNU_SOURCE
  19
  20 #include <stdlib.h>
  21 #include <string.h>
  22
  23 #include <json-c/json.h>
  24 #include <afb/afb-req-itf.h>
  25
  26 #include "afb-subcall.h"
  27 #include "afb-msg-json.h"
  28 #include "afb-apiset.h"
  29 #include "afb-context.h"
  30 #include "afb-xreq.h"
  31 #include "afb-cred.h"
  32 #include "verbose.h"
  33 #include "jobs.h"
  34
  35 struct subcall;
  36
  37 static void subcall_destroy(struct afb_xreq *xreq);
  38 static void subcall_reply(struct afb_xreq *xreq, int iserror, struct json_object *obj);
  39 static int subcall_subscribe(struct afb_xreq *xreq, struct afb_event event);
  40 static int subcall_unsubscribe(struct afb_xreq *xreq, struct afb_event event);
  41
  42 const struct afb_xreq_query_itf afb_subcall_xreq_itf = {
  43         .reply = subcall_reply,
  44         .unref = subcall_destroy,
  45         .subscribe = subcall_subscribe,
  46         .unsubscribe = subcall_unsubscribe
  47 };
  48
  49 struct subcall
  50 {
  51         struct afb_xreq xreq;
  52         struct afb_xreq *caller;
  53         void (*callback)(void*, int, struct json_object*);
  54         void *closure;
  55 };
  56
  57 static void subcall_destroy(struct afb_xreq *xreq)
  58 {
  59         struct subcall *subcall = CONTAINER_OF_XREQ(struct subcall, xreq);
  60
  61         json_object_put(subcall->xreq.json);
  62         afb_cred_unref(subcall->xreq.cred);
  63         afb_xreq_unref(subcall->caller);
  64         free(subcall);
  65 }
  66
  67 static void subcall_reply(struct afb_xreq *xreq, int iserror, struct json_object *obj)
  68 {
  69         struct subcall *subcall = CONTAINER_OF_XREQ(struct subcall, xreq);
  70
  71         subcall->callback(subcall->closure, iserror, obj);
  72         json_object_put(obj);
  73 }
  74
  75 static int subcall_subscribe(struct afb_xreq *xreq, struct afb_event event)
  76 {
  77         struct subcall *subcall = CONTAINER_OF_XREQ(struct subcall, xreq);
  78
  79         return afb_xreq_subscribe(subcall->caller, event);
  80 }
  81
  82 static int subcall_unsubscribe(struct afb_xreq *xreq, struct afb_event event)
  83 {
  84         struct subcall *subcall = CONTAINER_OF_XREQ(struct subcall, xreq);
  85
  86         return afb_xreq_unsubscribe(subcall->caller, event);
  87 }
  88
  89 static struct subcall *create_subcall(struct afb_xreq *caller, const char *api, const char *verb, struct json_object *args, void (*callback)(void*, int, struct json_object*), void *closure)
  90 {
  91         struct subcall *subcall;
  92         size_t lenapi, lenverb;
  93         char *copy;
  94
  95         lenapi = 1 + strlen(api);
  96         lenverb = 1 + strlen(verb);
  97         subcall = malloc(lenapi + lenverb + sizeof *subcall);
  98         if (subcall == NULL) {
  99                 return NULL;
 100         }
 101         afb_xreq_init(&subcall->xreq, &afb_subcall_xreq_itf);
 102         afb_context_subinit(&subcall->xreq.context, &caller->context);
 103         subcall->xreq.cred = afb_cred_addref(caller->cred);
 104         subcall->xreq.json = args;
 105         copy = (char*)&subcall[1];
 106         memcpy(copy, api, lenapi);
 107         subcall->xreq.api = copy;
 108         copy = &copy[lenapi];
 109         memcpy(copy, verb, lenverb);
 110         subcall->xreq.verb = copy;
 111         subcall->caller = caller;
 112         subcall->callback = callback;
 113         subcall->closure = closure;
 114         afb_xreq_addref(caller);
 115         json_object_get(args);
 116         return subcall;
 117 }
 118
 119 void afb_subcall(
 120                 struct afb_xreq *caller,
 121                 const char *api,
 122                 const char *verb,
 123                 struct json_object *args,
 124                 void (*callback)(void*, int, struct json_object*),
 125                 void *closure
 126 )
 127 {
 128         struct subcall *subcall;
 129
 130         subcall = create_subcall(caller, api, verb, args, callback, closure);
 131         if (subcall == NULL) {
 132                 callback(closure, 1, afb_msg_json_internal_error());
 133                 return;
 134         }
 135
 136         afb_xreq_process(&subcall->xreq, caller->apiset);
 137 }
 138
 139 struct subcall_sync
 140 {
 141         struct afb_xreq *caller;
 142         const char *api;
 143         const char *verb;
 144         struct json_object *args;
 145         struct jobloop *jobloop;
 146         struct json_object *result;
 147         int iserror;
 148 };
 149
 150 static void subcall_sync_leave(struct subcall_sync *sync)
 151 {
 152         struct jobloop *jobloop = sync->jobloop;
 153         sync->jobloop = NULL;
 154         if (jobloop)
 155                 jobs_leave(jobloop);
 156 }
 157
 158 static void subcall_sync_reply(void *closure, int iserror, struct json_object *obj)
 159 {
 160         struct subcall_sync *sync = closure;
 161
 162         sync->iserror = iserror;
 163         sync->result = obj;
 164         json_object_get(obj);
 165         subcall_sync_leave(sync);
 166 }
 167
 168 static void subcall_sync_enter(int signum, void *closure, struct jobloop *jobloop)
 169 {
 170         struct subcall_sync *sync = closure;
 171
 172         if (!signum) {
 173                 sync->jobloop = jobloop;
 174                 afb_xreq_unhooked_subcall(sync->caller, sync->api, sync->verb, sync->args, subcall_sync_reply, sync);
 175         } else {
 176                 sync->result = json_object_get(afb_msg_json_internal_error());
 177                 sync->iserror = 1;
 178                 subcall_sync_leave(sync);
 179         }
 180 }
 181
 182 int afb_subcall_sync(
 183                 struct afb_xreq *caller,
 184                 const char *api,
 185                 const char *verb,
 186                 struct json_object *args,
 187                 struct json_object **result
 188 )
 189 {
 190         int rc;
 191         struct subcall_sync sync;
 192
 193         sync.caller = caller;
 194         sync.api = api;
 195         sync.verb = verb;
 196         sync.args = args;
 197         sync.jobloop = NULL;
 198         sync.result = NULL;
 199         sync.iserror = 1;
 200
 201         rc = jobs_enter(NULL, 0, subcall_sync_enter, &sync);
 202         if (rc < 0) {
 203                 sync.result = json_object_get(afb_msg_json_internal_error());
 204                 sync.iserror = 1;
 205         }
 206         rc = !sync.iserror;
 207         *result = sync.result;
 208         return rc;
 209 }
 210
 211