diff options
Diffstat (limited to 'src/sp/protocol/survey0/respond.c')
| -rw-r--r-- | src/sp/protocol/survey0/respond.c | 693 |
1 files changed, 693 insertions, 0 deletions
diff --git a/src/sp/protocol/survey0/respond.c b/src/sp/protocol/survey0/respond.c new file mode 100644 index 00000000..ad551c8f --- /dev/null +++ b/src/sp/protocol/survey0/respond.c @@ -0,0 +1,693 @@ +// +// Copyright 2020 Staysail Systems, Inc. <info@staysail.tech> +// Copyright 2018 Capitar IT Group BV <info@capitar.com> +// +// This software is supplied under the terms of the MIT License, a +// copy of which should be located in the distribution where this +// file was obtained (LICENSE.txt). A copy of the license may also be +// found online at https://opensource.org/licenses/MIT. +// + +#include <stdlib.h> +#include <string.h> + +#include "core/nng_impl.h" +#include "nng/protocol/survey0/respond.h" + +// Respondent protocol. The RESPONDENT protocol is the "replier" side of +// the surveyor pattern. This is useful for building service discovery, or +// voting algorithms, for example. + +#ifndef NNI_PROTO_SURVEYOR_V0 +#define NNI_PROTO_SURVEYOR_V0 NNI_PROTO(6, 2) +#endif + +#ifndef NNI_PROTO_RESPONDENT_V0 +#define NNI_PROTO_RESPONDENT_V0 NNI_PROTO(6, 3) +#endif + +typedef struct resp0_pipe resp0_pipe; +typedef struct resp0_sock resp0_sock; +typedef struct resp0_ctx resp0_ctx; + +static void resp0_pipe_send_cb(void *); +static void resp0_pipe_recv_cb(void *); +static void resp0_pipe_fini(void *); + +struct resp0_ctx { + resp0_sock * sock; + uint32_t pipe_id; + resp0_pipe * spipe; // send pipe + nni_aio * saio; // send aio + nni_aio * raio; // recv aio + nni_list_node sqnode; + nni_list_node rqnode; + size_t btrace_len; + uint32_t btrace[NNI_MAX_MAX_TTL + 1]; +}; + +// resp0_sock is our per-socket protocol private structure. +struct resp0_sock { + nni_mtx mtx; + nni_atomic_int ttl; + nni_id_map pipes; + resp0_ctx ctx; + nni_list recvpipes; + nni_list recvq; + nni_pollable readable; + nni_pollable writable; +}; + +// resp0_pipe is our per-pipe protocol private structure. +struct resp0_pipe { + nni_pipe * npipe; + resp0_sock * psock; + bool busy; + bool closed; + uint32_t id; + nni_list sendq; // contexts waiting to send + nni_aio aio_send; + nni_aio aio_recv; + nni_list_node rnode; // receivable linkage +}; + +static void +resp0_ctx_close(void *arg) +{ + resp0_ctx * ctx = arg; + resp0_sock *s = ctx->sock; + nni_aio * aio; + + // complete any outstanding operations here, cancellation, etc. + + nni_mtx_lock(&s->mtx); + if ((aio = ctx->saio) != NULL) { + resp0_pipe *p = ctx->spipe; + ctx->saio = NULL; + ctx->spipe = NULL; + nni_list_remove(&p->sendq, ctx); + nni_aio_finish_error(aio, NNG_ECLOSED); + } + if ((aio = ctx->raio) != NULL) { + ctx->raio = NULL; + nni_list_remove(&s->recvq, ctx); + nni_aio_finish_error(aio, NNG_ECLOSED); + } + nni_mtx_unlock(&s->mtx); +} + +static void +resp0_ctx_fini(void *arg) +{ + resp0_ctx *ctx = arg; + + resp0_ctx_close(ctx); +} + +static int +resp0_ctx_init(void *carg, void *sarg) +{ + resp0_sock *s = sarg; + resp0_ctx * ctx = carg; + + NNI_LIST_NODE_INIT(&ctx->sqnode); + NNI_LIST_NODE_INIT(&ctx->rqnode); + ctx->btrace_len = 0; + ctx->sock = s; + ctx->pipe_id = 0; + + return (0); +} + +static void +resp0_ctx_cancel_send(nni_aio *aio, void *arg, int rv) +{ + resp0_ctx * ctx = arg; + resp0_sock *s = ctx->sock; + + nni_mtx_lock(&s->mtx); + if (ctx->saio != aio) { + nni_mtx_unlock(&s->mtx); + return; + } + nni_list_node_remove(&ctx->sqnode); + ctx->saio = NULL; + nni_mtx_unlock(&s->mtx); + nni_msg_header_clear(nni_aio_get_msg(aio)); // reset the headers + nni_aio_finish_error(aio, rv); +} + +static void +resp0_ctx_send(void *arg, nni_aio *aio) +{ + resp0_ctx * ctx = arg; + resp0_sock *s = ctx->sock; + resp0_pipe *p; + nni_msg * msg; + size_t len; + uint32_t pid; + int rv; + + if (nni_aio_begin(aio) != 0) { + return; + } + msg = nni_aio_get_msg(aio); + nni_msg_header_clear(msg); + + if (ctx == &s->ctx) { + // We can't send anymore, because only one send per request. + nni_pollable_clear(&s->writable); + } + + nni_mtx_lock(&s->mtx); + if ((rv = nni_aio_schedule(aio, resp0_ctx_cancel_send, ctx)) != 0) { + nni_mtx_unlock(&s->mtx); + nni_aio_finish_error(aio, rv); + return; + } + + if ((len = ctx->btrace_len) == 0) { + nni_mtx_unlock(&s->mtx); + nni_aio_finish_error(aio, NNG_ESTATE); + return; + } + pid = ctx->pipe_id; + ctx->pipe_id = 0; + ctx->btrace_len = 0; + + if ((rv = nni_msg_header_append(msg, ctx->btrace, len)) != 0) { + nni_mtx_unlock(&s->mtx); + nni_aio_finish_error(aio, rv); + return; + } + + if ((p = nni_id_get(&s->pipes, pid)) == NULL) { + // Surveyor has left the building. Just discard the reply. + nni_mtx_unlock(&s->mtx); + nni_aio_set_msg(aio, NULL); + nni_aio_finish(aio, 0, nni_msg_len(msg)); + nni_msg_free(msg); + return; + } + + if (!p->busy) { + p->busy = true; + len = nni_msg_len(msg); + nni_aio_set_msg(&p->aio_send, msg); + nni_pipe_send(p->npipe, &p->aio_send); + nni_mtx_unlock(&s->mtx); + + nni_aio_set_msg(aio, NULL); + nni_aio_finish(aio, 0, len); + return; + } + + ctx->saio = aio; + ctx->spipe = p; + nni_list_append(&p->sendq, ctx); + nni_mtx_unlock(&s->mtx); +} + +static void +resp0_sock_fini(void *arg) +{ + resp0_sock *s = arg; + + nni_id_map_fini(&s->pipes); + resp0_ctx_fini(&s->ctx); + nni_pollable_fini(&s->writable); + nni_pollable_fini(&s->readable); + nni_mtx_fini(&s->mtx); +} + +static int +resp0_sock_init(void *arg, nni_sock *nsock) +{ + resp0_sock *s = arg; + + NNI_ARG_UNUSED(nsock); + + nni_mtx_init(&s->mtx); + nni_id_map_init(&s->pipes, 0, 0, false); + + NNI_LIST_INIT(&s->recvq, resp0_ctx, rqnode); + NNI_LIST_INIT(&s->recvpipes, resp0_pipe, rnode); + + nni_atomic_init(&s->ttl); + nni_atomic_set(&s->ttl, 8); // Per RFC + + (void) resp0_ctx_init(&s->ctx, s); + + // We start off without being either readable or writable. + // Readability comes when there is something on the socket. + nni_pollable_init(&s->writable); + nni_pollable_init(&s->readable); + return (0); +} + +static void +resp0_sock_open(void *arg) +{ + NNI_ARG_UNUSED(arg); +} + +static void +resp0_sock_close(void *arg) +{ + resp0_sock *s = arg; + + resp0_ctx_close(&s->ctx); +} + +static void +resp0_pipe_stop(void *arg) +{ + resp0_pipe *p = arg; + + nni_aio_stop(&p->aio_send); + nni_aio_stop(&p->aio_recv); +} + +static void +resp0_pipe_fini(void *arg) +{ + resp0_pipe *p = arg; + nng_msg * msg; + + if ((msg = nni_aio_get_msg(&p->aio_recv)) != NULL) { + nni_aio_set_msg(&p->aio_recv, NULL); + nni_msg_free(msg); + } + nni_aio_fini(&p->aio_send); + nni_aio_fini(&p->aio_recv); +} + +static int +resp0_pipe_init(void *arg, nni_pipe *npipe, void *s) +{ + resp0_pipe *p = arg; + + nni_aio_init(&p->aio_recv, resp0_pipe_recv_cb, p); + nni_aio_init(&p->aio_send, resp0_pipe_send_cb, p); + + NNI_LIST_INIT(&p->sendq, resp0_ctx, sqnode); + + p->npipe = npipe; + p->psock = s; + p->busy = false; + p->id = nni_pipe_id(npipe); + + return (0); +} + +static int +resp0_pipe_start(void *arg) +{ + resp0_pipe *p = arg; + resp0_sock *s = p->psock; + int rv; + + if (nni_pipe_peer(p->npipe) != NNI_PROTO_SURVEYOR_V0) { + return (NNG_EPROTO); + } + + nni_mtx_lock(&s->mtx); + rv = nni_id_set(&s->pipes, p->id, p); + nni_mtx_unlock(&s->mtx); + if (rv != 0) { + return (rv); + } + + nni_pipe_recv(p->npipe, &p->aio_recv); + return (rv); +} + +static void +resp0_pipe_close(void *arg) +{ + resp0_pipe *p = arg; + resp0_sock *s = p->psock; + resp0_ctx * ctx; + + nni_aio_close(&p->aio_send); + nni_aio_close(&p->aio_recv); + + nni_mtx_lock(&s->mtx); + p->closed = true; + while ((ctx = nni_list_first(&p->sendq)) != NULL) { + nni_aio *aio; + nni_msg *msg; + nni_list_remove(&p->sendq, ctx); + aio = ctx->saio; + ctx->saio = NULL; + msg = nni_aio_get_msg(aio); + nni_aio_set_msg(aio, NULL); + nni_aio_finish(aio, 0, nni_msg_len(msg)); + nni_msg_free(msg); + } + if (p->id == s->ctx.pipe_id) { + // Make sure user space knows they can send a message to us, + // which we will happily discard. + nni_pollable_raise(&s->writable); + } + nni_id_remove(&s->pipes, p->id); + nni_mtx_unlock(&s->mtx); +} + +static void +resp0_pipe_send_cb(void *arg) +{ + resp0_pipe *p = arg; + resp0_sock *s = p->psock; + resp0_ctx * ctx; + nni_aio * aio; + nni_msg * msg; + size_t len; + + if (nni_aio_result(&p->aio_send) != 0) { + nni_msg_free(nni_aio_get_msg(&p->aio_send)); + nni_aio_set_msg(&p->aio_send, NULL); + nni_pipe_close(p->npipe); + return; + } + nni_mtx_lock(&s->mtx); + p->busy = false; + if ((ctx = nni_list_first(&p->sendq)) == NULL) { + // Nothing else to send. + if (p->id == s->ctx.pipe_id) { + // Mark us ready for the other side to send! + nni_pollable_raise(&s->writable); + } + nni_mtx_unlock(&s->mtx); + return; + } + + nni_list_remove(&p->sendq, ctx); + aio = ctx->saio; + ctx->saio = NULL; + ctx->spipe = NULL; + p->busy = true; + msg = nni_aio_get_msg(aio); + len = nni_msg_len(msg); + nni_aio_set_msg(aio, NULL); + nni_aio_set_msg(&p->aio_send, msg); + nni_pipe_send(p->npipe, &p->aio_send); + + nni_mtx_unlock(&s->mtx); + + nni_aio_finish_sync(aio, 0, len); +} + +static void +resp0_cancel_recv(nni_aio *aio, void *arg, int rv) +{ + resp0_ctx * ctx = arg; + resp0_sock *s = ctx->sock; + + nni_mtx_lock(&s->mtx); + if (ctx->raio == aio) { + nni_list_remove(&s->recvq, ctx); + ctx->raio = NULL; + nni_aio_finish_error(aio, rv); + } + nni_mtx_unlock(&s->mtx); +} + +static void +resp0_ctx_recv(void *arg, nni_aio *aio) +{ + resp0_ctx * ctx = arg; + resp0_sock *s = ctx->sock; + resp0_pipe *p; + size_t len; + nni_msg * msg; + + if (nni_aio_begin(aio) != 0) { + return; + } + nni_mtx_lock(&s->mtx); + if ((p = nni_list_first(&s->recvpipes)) == NULL) { + int rv; + rv = nni_aio_schedule(aio, resp0_cancel_recv, ctx); + if (rv != 0) { + nni_mtx_unlock(&s->mtx); + nni_aio_finish_error(aio, rv); + return; + } + // We cannot have two concurrent receive requests on the same + // context... + if (ctx->raio != NULL) { + nni_mtx_unlock(&s->mtx); + nni_aio_finish_error(aio, NNG_ESTATE); + return; + } + ctx->raio = aio; + nni_list_append(&s->recvq, ctx); + nni_mtx_unlock(&s->mtx); + return; + } + msg = nni_aio_get_msg(&p->aio_recv); + nni_aio_set_msg(&p->aio_recv, NULL); + nni_list_remove(&s->recvpipes, p); + if (nni_list_empty(&s->recvpipes)) { + nni_pollable_clear(&s->readable); + } + nni_pipe_recv(p->npipe, &p->aio_recv); + + len = nni_msg_header_len(msg); + memcpy(ctx->btrace, nni_msg_header(msg), len); + ctx->btrace_len = len; + ctx->pipe_id = p->id; + if (ctx == &s->ctx) { + nni_pollable_raise(&s->writable); + } + nni_mtx_unlock(&s->mtx); + + nni_msg_header_clear(msg); + nni_aio_set_msg(aio, msg); + nni_aio_finish(aio, 0, nni_msg_len(msg)); +} + +static void +resp0_pipe_recv_cb(void *arg) +{ + resp0_pipe *p = arg; + resp0_sock *s = p->psock; + resp0_ctx * ctx; + nni_msg * msg; + nni_aio * aio; + int hops; + size_t len; + int ttl; + + if (nni_aio_result(&p->aio_recv) != 0) { + nni_pipe_close(p->npipe); + return; + } + + ttl = nni_atomic_get(&s->ttl); + msg = nni_aio_get_msg(&p->aio_recv); + nni_msg_set_pipe(msg, p->id); + + // Move backtrace from body to header + hops = 1; + for (;;) { + bool end = 0; + uint8_t *body; + + if (hops > ttl) { + goto drop; + } + hops++; + if (nni_msg_len(msg) < 4) { + // Peer is speaking garbage, kick it. + nni_msg_free(msg); + nni_aio_set_msg(&p->aio_recv, NULL); + nni_pipe_close(p->npipe); + return; + } + body = nni_msg_body(msg); + end = ((body[0] & 0x80u) != 0); + if (nni_msg_header_append(msg, body, 4) != 0) { + goto drop; + } + nni_msg_trim(msg, 4); + if (end) { + break; + } + } + + len = nni_msg_header_len(msg); + + nni_mtx_lock(&s->mtx); + + if (p->closed) { + // If pipe was closed, we just abandon the data from it. + nni_aio_set_msg(&p->aio_recv, NULL); + nni_mtx_unlock(&s->mtx); + nni_msg_free(msg); + return; + } + if ((ctx = nni_list_first(&s->recvq)) == NULL) { + // No one blocked in recv, stall. + nni_list_append(&s->recvpipes, p); + nni_pollable_raise(&s->readable); + nni_mtx_unlock(&s->mtx); + return; + } + + nni_list_remove(&s->recvq, ctx); + aio = ctx->raio; + ctx->raio = NULL; + nni_aio_set_msg(&p->aio_recv, NULL); + + // Start the next receive. + nni_pipe_recv(p->npipe, &p->aio_recv); + + ctx->btrace_len = len; + memcpy(ctx->btrace, nni_msg_header(msg), len); + nni_msg_header_clear(msg); + ctx->pipe_id = p->id; + + if ((ctx == &s->ctx) && (!p->busy)) { + nni_pollable_raise(&s->writable); + } + nni_mtx_unlock(&s->mtx); + + nni_aio_set_msg(aio, msg); + nni_aio_finish_sync(aio, 0, nni_msg_len(msg)); + return; + +drop: + nni_msg_free(msg); + nni_aio_set_msg(&p->aio_recv, NULL); + nni_pipe_recv(p->npipe, &p->aio_recv); +} + +static int +resp0_sock_set_max_ttl(void *arg, const void *buf, size_t sz, nni_opt_type t) +{ + resp0_sock *s = arg; + int ttl; + int rv; + + if ((rv = nni_copyin_int(&ttl, buf, sz, 1, NNI_MAX_MAX_TTL, t)) == 0) { + nni_atomic_set(&s->ttl, ttl); + } + return (rv); +} + +static int +resp0_sock_get_max_ttl(void *arg, void *buf, size_t *szp, nni_opt_type t) +{ + resp0_sock *s = arg; + return (nni_copyout_int(nni_atomic_get(&s->ttl), buf, szp, t)); +} + +static int +resp0_sock_get_sendfd(void *arg, void *buf, size_t *szp, nni_opt_type t) +{ + resp0_sock *s = arg; + int rv; + int fd; + + if ((rv = nni_pollable_getfd(&s->writable, &fd)) != 0) { + return (rv); + } + return (nni_copyout_int(fd, buf, szp, t)); +} + +static int +resp0_sock_get_recvfd(void *arg, void *buf, size_t *szp, nni_opt_type t) +{ + resp0_sock *s = arg; + int rv; + int fd; + + if ((rv = nni_pollable_getfd(&s->readable, &fd)) != 0) { + return (rv); + } + return (nni_copyout_int(fd, buf, szp, t)); +} + +static void +resp0_sock_send(void *arg, nni_aio *aio) +{ + resp0_sock *s = arg; + + resp0_ctx_send(&s->ctx, aio); +} + +static void +resp0_sock_recv(void *arg, nni_aio *aio) +{ + resp0_sock *s = arg; + + resp0_ctx_recv(&s->ctx, aio); +} + +static nni_proto_pipe_ops resp0_pipe_ops = { + .pipe_size = sizeof(resp0_pipe), + .pipe_init = resp0_pipe_init, + .pipe_fini = resp0_pipe_fini, + .pipe_start = resp0_pipe_start, + .pipe_close = resp0_pipe_close, + .pipe_stop = resp0_pipe_stop, +}; + +static nni_proto_ctx_ops resp0_ctx_ops = { + .ctx_size = sizeof(resp0_ctx), + .ctx_init = resp0_ctx_init, + .ctx_fini = resp0_ctx_fini, + .ctx_send = resp0_ctx_send, + .ctx_recv = resp0_ctx_recv, +}; + +static nni_option resp0_sock_options[] = { + { + .o_name = NNG_OPT_MAXTTL, + .o_get = resp0_sock_get_max_ttl, + .o_set = resp0_sock_set_max_ttl, + }, + { + .o_name = NNG_OPT_RECVFD, + .o_get = resp0_sock_get_recvfd, + .o_set = NULL, + }, + { + .o_name = NNG_OPT_SENDFD, + .o_get = resp0_sock_get_sendfd, + .o_set = NULL, + }, + // terminate list + { + .o_name = NULL, + }, +}; + +static nni_proto_sock_ops resp0_sock_ops = { + .sock_size = sizeof(resp0_sock), + .sock_init = resp0_sock_init, + .sock_fini = resp0_sock_fini, + .sock_open = resp0_sock_open, + .sock_close = resp0_sock_close, + .sock_send = resp0_sock_send, + .sock_recv = resp0_sock_recv, + .sock_options = resp0_sock_options, +}; + +static nni_proto resp0_proto = { + .proto_version = NNI_PROTOCOL_VERSION, + .proto_self = { NNI_PROTO_RESPONDENT_V0, "respondent" }, + .proto_peer = { NNI_PROTO_SURVEYOR_V0, "surveyor" }, + .proto_flags = NNI_PROTO_FLAG_SNDRCV, + .proto_sock_ops = &resp0_sock_ops, + .proto_pipe_ops = &resp0_pipe_ops, + .proto_ctx_ops = &resp0_ctx_ops, +}; + +int +nng_respondent0_open(nng_socket *sidp) +{ + return (nni_proto_open(sidp, &resp0_proto)); +} |
