From 3ea10077534cb1dcb1597ffcf85e601fa0c0e27b Mon Sep 17 00:00:00 2001 From: "Justin M. Keyes" Date: Mon, 13 Mar 2017 15:02:37 +0100 Subject: api: nvim_get_mode() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Asynchronous API functions are served immediately, which means pending input could change the state of Nvim shortly after an async API function result is returned. nvim_get_mode() is different: - If RPCs are known to be blocked, it responds immediately (without flushing the input/event queue) - else it is handled just-in-time before waiting for input, after pending input was processed. This makes the result more reliable (but not perfect). Internally this is handled as a special case, but _semantically_ nothing has changed: API users never know when input flushes, so this internal special-case doesn't violate that. As far as API users are concerned, nvim_get_mode() is just another asynchronous API function. In all cases nvim_get_mode() never blocks for more than the time it takes to flush the input/event queue (~µs). Note: This doesn't address #6166; nvim_get_mode() will provoke #6166 if e.g. `d` is operator-pending. Closes #6159 --- src/nvim/msgpack_rpc/channel.c | 10 ++++++++++ src/nvim/msgpack_rpc/helpers.c | 2 +- 2 files changed, 11 insertions(+), 1 deletion(-) (limited to 'src/nvim/msgpack_rpc') diff --git a/src/nvim/msgpack_rpc/channel.c b/src/nvim/msgpack_rpc/channel.c index 59594357de..799e6eadef 100644 --- a/src/nvim/msgpack_rpc/channel.c +++ b/src/nvim/msgpack_rpc/channel.c @@ -28,7 +28,9 @@ #include "nvim/map.h" #include "nvim/log.h" #include "nvim/misc1.h" +#include "nvim/state.h" #include "nvim/lib/kvec.h" +#include "nvim/os/input.h" #define CHANNEL_BUFFER_SIZE 0xffff @@ -433,6 +435,14 @@ static void handle_request(Channel *channel, msgpack_object *request) handler.async = true; } + if (handler.async) { + char buf[256] = { 0 }; + memcpy(buf, method->via.bin.ptr, MIN(255, method->via.bin.size)); + if (strcmp("nvim_get_mode", buf) == 0) { + handler.async = input_blocking(); + } + } + RequestEvent *event_data = xmalloc(sizeof(RequestEvent)); event_data->channel = channel; event_data->handler = handler; diff --git a/src/nvim/msgpack_rpc/helpers.c b/src/nvim/msgpack_rpc/helpers.c index 0228582d37..91ef5524ea 100644 --- a/src/nvim/msgpack_rpc/helpers.c +++ b/src/nvim/msgpack_rpc/helpers.c @@ -76,7 +76,7 @@ typedef struct { size_t idx; } MPToAPIObjectStackItem; -/// Convert type used by msgpack parser to Neovim own API type +/// Convert type used by msgpack parser to Nvim API type. /// /// @param[in] obj Msgpack value to convert. /// @param[out] arg Location where result of conversion will be saved. -- cgit From acfd2a2a29ae852ecc965ca888eb5049400bf39d Mon Sep 17 00:00:00 2001 From: "Justin M. Keyes" Date: Tue, 14 Mar 2017 00:44:03 +0100 Subject: input.c: Process only safe events before blocking. Introduce multiqueue_process_priority() to process only events at or above a certain priority. --- src/nvim/msgpack_rpc/channel.c | 32 +++++++++++++++++--------------- 1 file changed, 17 insertions(+), 15 deletions(-) (limited to 'src/nvim/msgpack_rpc') diff --git a/src/nvim/msgpack_rpc/channel.c b/src/nvim/msgpack_rpc/channel.c index 799e6eadef..9e43924db1 100644 --- a/src/nvim/msgpack_rpc/channel.c +++ b/src/nvim/msgpack_rpc/channel.c @@ -435,24 +435,26 @@ static void handle_request(Channel *channel, msgpack_object *request) handler.async = true; } - if (handler.async) { - char buf[256] = { 0 }; - memcpy(buf, method->via.bin.ptr, MIN(255, method->via.bin.size)); - if (strcmp("nvim_get_mode", buf) == 0) { - handler.async = input_blocking(); - } - } - - RequestEvent *event_data = xmalloc(sizeof(RequestEvent)); - event_data->channel = channel; - event_data->handler = handler; - event_data->args = args; - event_data->request_id = request_id; + RequestEvent *evdata = xmalloc(sizeof(RequestEvent)); + evdata->channel = channel; + evdata->handler = handler; + evdata->args = args; + evdata->request_id = request_id; incref(channel); if (handler.async) { - on_request_event((void **)&event_data); + bool is_get_mode = sizeof("nvim_get_mode") - 1 == method->via.bin.size + && !strncmp("nvim_get_mode", method->via.bin.ptr, method->via.bin.size); + + if (is_get_mode && !input_blocking()) { + // Schedule on the main loop with special priority. #6247 + Event ev = event_create(kEvPriorityAsync, on_request_event, 1, evdata); + multiqueue_put_event(channel->events, ev); + } else { + // Invoke immediately. + on_request_event((void **)&evdata); + } } else { - multiqueue_put(channel->events, on_request_event, 1, event_data); + multiqueue_put(channel->events, on_request_event, 1, evdata); } } -- cgit From f17a8185191b778960953508a5bf9b5f95b0560c Mon Sep 17 00:00:00 2001 From: "Justin M. Keyes" Date: Thu, 27 Apr 2017 13:54:54 +0200 Subject: api/nvim_get_mode: Use child-queue instead of "priority". --- src/nvim/msgpack_rpc/channel.c | 7 +++---- src/nvim/msgpack_rpc/channel.h | 5 +++++ 2 files changed, 8 insertions(+), 4 deletions(-) (limited to 'src/nvim/msgpack_rpc') diff --git a/src/nvim/msgpack_rpc/channel.c b/src/nvim/msgpack_rpc/channel.c index 9e43924db1..911f2a6fa4 100644 --- a/src/nvim/msgpack_rpc/channel.c +++ b/src/nvim/msgpack_rpc/channel.c @@ -28,7 +28,6 @@ #include "nvim/map.h" #include "nvim/log.h" #include "nvim/misc1.h" -#include "nvim/state.h" #include "nvim/lib/kvec.h" #include "nvim/os/input.h" @@ -91,6 +90,7 @@ static msgpack_sbuffer out_buffer; /// Initializes the module void channel_init(void) { + ch_before_blocking_events = multiqueue_new_child(main_loop.events); channels = pmap_new(uint64_t)(); event_strings = pmap_new(cstr_t)(); msgpack_sbuffer_init(&out_buffer); @@ -446,9 +446,8 @@ static void handle_request(Channel *channel, msgpack_object *request) && !strncmp("nvim_get_mode", method->via.bin.ptr, method->via.bin.size); if (is_get_mode && !input_blocking()) { - // Schedule on the main loop with special priority. #6247 - Event ev = event_create(kEvPriorityAsync, on_request_event, 1, evdata); - multiqueue_put_event(channel->events, ev); + // Defer the event to a special queue used by os/input.c. #6247 + multiqueue_put(ch_before_blocking_events, on_request_event, 1, evdata); } else { // Invoke immediately. on_request_event((void **)&evdata); diff --git a/src/nvim/msgpack_rpc/channel.h b/src/nvim/msgpack_rpc/channel.h index 0d92976d02..f8fe6f129b 100644 --- a/src/nvim/msgpack_rpc/channel.h +++ b/src/nvim/msgpack_rpc/channel.h @@ -11,6 +11,11 @@ #define METHOD_MAXLEN 512 +/// HACK: os/input.c drains this queue immediately before blocking for input. +/// Events on this queue are async-safe, but they need the resolved state +/// of os_inchar(), so they are processed "just-in-time". +MultiQueue *ch_before_blocking_events; + #ifdef INCLUDE_GENERATED_DECLARATIONS # include "msgpack_rpc/channel.h.generated.h" #endif -- cgit