| /* |
| * |
| * Copyright 2015, Google Inc. |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are |
| * met: |
| * |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above |
| * copyright notice, this list of conditions and the following disclaimer |
| * in the documentation and/or other materials provided with the |
| * distribution. |
| * * Neither the name of Google Inc. nor the names of its |
| * contributors may be used to endorse or promote products derived from |
| * this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| * |
| */ |
| |
| #include "src/core/iomgr/sockaddr.h" |
| |
| #include <grpc/grpc.h> |
| |
| #include <stdlib.h> |
| #include <string.h> |
| |
| #include "src/core/channel/census_filter.h" |
| #include "src/core/channel/channel_args.h" |
| #include "src/core/channel/client_channel.h" |
| #include "src/core/channel/client_setup.h" |
| #include "src/core/channel/connected_channel.h" |
| #include "src/core/channel/http_client_filter.h" |
| #include "src/core/channel/http_filter.h" |
| #include "src/core/iomgr/endpoint.h" |
| #include "src/core/iomgr/resolve_address.h" |
| #include "src/core/iomgr/tcp_client.h" |
| #include "src/core/surface/channel.h" |
| #include "src/core/surface/client.h" |
| #include "src/core/support/string.h" |
| #include "src/core/transport/chttp2_transport.h" |
| #include <grpc/support/alloc.h> |
| #include <grpc/support/log.h> |
| #include <grpc/support/sync.h> |
| #include <grpc/support/useful.h> |
| |
| typedef struct setup setup; |
| |
| /* A single setup request (started via initiate) */ |
| typedef struct { |
| grpc_client_setup_request *cs_request; |
| setup *setup; |
| /* Resolved addresses, or null if resolution not yet completed */ |
| grpc_resolved_addresses *resolved; |
| /* which address in resolved should we pick for the next connection attempt */ |
| size_t resolved_index; |
| } request; |
| |
| /* Global setup logic (may be running many simultaneous setup requests, but |
| with only one 'active' */ |
| struct setup { |
| const char *target; |
| grpc_transport_setup_callback setup_callback; |
| void *setup_user_data; |
| }; |
| |
| static int maybe_try_next_resolved(request *r); |
| |
| static void done(request *r, int was_successful) { |
| grpc_client_setup_request_finish(r->cs_request, was_successful); |
| if (r->resolved) { |
| grpc_resolved_addresses_destroy(r->resolved); |
| } |
| gpr_free(r); |
| } |
| |
| /* connection callback: tcp is either valid, or null on error */ |
| static void on_connect(void *rp, grpc_endpoint *tcp) { |
| request *r = rp; |
| |
| if (!grpc_client_setup_request_should_continue(r->cs_request)) { |
| if (tcp) { |
| grpc_endpoint_shutdown(tcp); |
| grpc_endpoint_destroy(tcp); |
| } |
| done(r, 0); |
| return; |
| } |
| |
| if (!tcp) { |
| if (!maybe_try_next_resolved(r)) { |
| done(r, 0); |
| return; |
| } else { |
| return; |
| } |
| } else if (grpc_client_setup_cb_begin(r->cs_request)) { |
| grpc_create_chttp2_transport( |
| r->setup->setup_callback, r->setup->setup_user_data, |
| grpc_client_setup_get_channel_args(r->cs_request), tcp, NULL, 0, |
| grpc_client_setup_get_mdctx(r->cs_request), 1); |
| grpc_client_setup_cb_end(r->cs_request); |
| done(r, 1); |
| return; |
| } else { |
| done(r, 0); |
| } |
| } |
| |
| /* attempt to connect to the next available resolved address */ |
| static int maybe_try_next_resolved(request *r) { |
| grpc_resolved_address *addr; |
| if (!r->resolved) return 0; |
| if (r->resolved_index == r->resolved->naddrs) return 0; |
| addr = &r->resolved->addrs[r->resolved_index++]; |
| grpc_tcp_client_connect(on_connect, r, (struct sockaddr *)&addr->addr, |
| addr->len, |
| grpc_client_setup_request_deadline(r->cs_request)); |
| return 1; |
| } |
| |
| /* callback for when our target address has been resolved */ |
| static void on_resolved(void *rp, grpc_resolved_addresses *resolved) { |
| request *r = rp; |
| |
| /* if we're not still the active request, abort */ |
| if (!grpc_client_setup_request_should_continue(r->cs_request)) { |
| if (resolved) { |
| grpc_resolved_addresses_destroy(resolved); |
| } |
| done(r, 0); |
| return; |
| } |
| |
| if (!resolved) { |
| done(r, 0); |
| return; |
| } else { |
| r->resolved = resolved; |
| r->resolved_index = 0; |
| if (!maybe_try_next_resolved(r)) { |
| done(r, 0); |
| } |
| } |
| } |
| |
| static void initiate_setup(void *sp, grpc_client_setup_request *cs_request) { |
| request *r = gpr_malloc(sizeof(request)); |
| r->setup = sp; |
| r->cs_request = cs_request; |
| r->resolved = NULL; |
| r->resolved_index = 0; |
| /* TODO(klempner): Make grpc_resolve_address respect deadline */ |
| grpc_resolve_address(r->setup->target, "http", on_resolved, r); |
| } |
| |
| static void done_setup(void *sp) { |
| setup *s = sp; |
| gpr_free((void *)s->target); |
| gpr_free(s); |
| } |
| |
| static grpc_transport_setup_result complete_setup(void *channel_stack, |
| grpc_transport *transport, |
| grpc_mdctx *mdctx) { |
| static grpc_channel_filter const *extra_filters[] = {&grpc_http_client_filter, |
| &grpc_http_filter}; |
| return grpc_client_channel_transport_setup_complete( |
| channel_stack, transport, extra_filters, GPR_ARRAY_SIZE(extra_filters), |
| mdctx); |
| } |
| |
| /* Create a client channel: |
| Asynchronously: - resolve target |
| - connect to it (trying alternatives as presented) |
| - perform handshakes */ |
| grpc_channel *grpc_channel_create(const char *target, |
| const grpc_channel_args *args) { |
| setup *s = gpr_malloc(sizeof(setup)); |
| grpc_mdctx *mdctx = grpc_mdctx_create(); |
| grpc_channel *channel = NULL; |
| #define MAX_FILTERS 3 |
| const grpc_channel_filter *filters[MAX_FILTERS]; |
| int n = 0; |
| filters[n++] = &grpc_client_surface_filter; |
| if (grpc_channel_args_is_census_enabled(args)) { |
| filters[n++] = &grpc_client_census_filter; |
| } |
| filters[n++] = &grpc_client_channel_filter; |
| GPR_ASSERT(n <= MAX_FILTERS); |
| channel = grpc_channel_create_from_filters(filters, n, args, mdctx, 1); |
| |
| s->target = gpr_strdup(target); |
| s->setup_callback = complete_setup; |
| s->setup_user_data = grpc_channel_get_channel_stack(channel); |
| |
| grpc_client_setup_create_and_attach(grpc_channel_get_channel_stack(channel), |
| args, mdctx, initiate_setup, done_setup, |
| s); |
| |
| return channel; |
| } |