dawn-cmake/generator/templates/dawn_wire/WireClient.cpp

692 lines
30 KiB
C++

//* Copyright 2017 The Dawn Authors
//*
//* 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.
#include "dawn_wire/Wire.h"
#include "dawn_wire/WireCmd.h"
#include "common/Assert.h"
#include <cstring>
#include <cstdlib>
#include <map>
#include <memory>
#include <string>
#include <vector>
namespace dawn_wire {
//* Client side implementation of the API, will serialize everything to memory to send to the server side.
namespace client {
class Device;
struct BuilderCallbackData {
bool Call(dawnBuilderErrorStatus status, const char* message) {
if (canCall && callback != nullptr) {
canCall = true;
callback(status, message, userdata1, userdata2);
return true;
}
return false;
}
//* For help with development, prints all builder errors by default.
dawnBuilderErrorCallback callback = nullptr;
dawnCallbackUserdata userdata1 = 0;
dawnCallbackUserdata userdata2 = 0;
bool canCall = true;
};
//* All non-Device objects of the client side have:
//* - A pointer to the device to get where to serialize commands
//* - The external reference count
//* - An ID that is used to refer to this object when talking with the server side
struct ObjectBase {
ObjectBase(Device* device, uint32_t refcount, uint32_t id)
:device(device), refcount(refcount), id(id) {
}
Device* device;
uint32_t refcount;
uint32_t id;
BuilderCallbackData builderCallback;
};
{% set special_objects = [
"device",
"buffer",
] %}
{% for type in by_category["object"] if not type.name.canonical_case() in special_objects %}
struct {{type.name.CamelCase()}} : ObjectBase {
using ObjectBase::ObjectBase;
};
{% endfor %}
struct Buffer : ObjectBase {
using ObjectBase::ObjectBase;
~Buffer() {
//* Callbacks need to be fired in all cases, as they can handle freeing resources
//* so we call them with "Unknown" status.
ClearMapRequests(DAWN_BUFFER_MAP_ASYNC_STATUS_UNKNOWN);
if (mappedData) {
free(mappedData);
}
}
void ClearMapRequests(dawnBufferMapAsyncStatus status) {
for (auto& it : requests) {
if (it.second.isWrite) {
it.second.writeCallback(status, nullptr, it.second.userdata);
} else {
it.second.readCallback(status, nullptr, it.second.userdata);
}
}
requests.clear();
}
//* We want to defer all the validation to the server, which means we could have multiple
//* map request in flight at a single time and need to track them separately.
//* On well-behaved applications, only one request should exist at a single time.
struct MapRequestData {
dawnBufferMapReadCallback readCallback = nullptr;
dawnBufferMapWriteCallback writeCallback = nullptr;
dawnCallbackUserdata userdata = 0;
uint32_t size = 0;
bool isWrite = false;
};
std::map<uint32_t, MapRequestData> requests;
uint32_t requestSerial = 0;
//* Only one mapped pointer can be active at a time because Unmap clears all the in-flight requests.
void* mappedData = nullptr;
size_t mappedDataSize = 0;
bool isWriteMapped = false;
};
//* TODO(cwallez@chromium.org): Do something with objects before they are destroyed ?
//* - Call still uncalled builder callbacks
template<typename T>
class ObjectAllocator {
public:
struct ObjectAndSerial {
ObjectAndSerial(std::unique_ptr<T> object, uint32_t serial)
: object(std::move(object)), serial(serial) {
}
std::unique_ptr<T> object;
uint32_t serial;
};
ObjectAllocator(Device* device) : mDevice(device) {
// ID 0 is nullptr
mObjects.emplace_back(nullptr, 0);
}
ObjectAndSerial* New() {
uint32_t id = GetNewId();
T* result = new T(mDevice, 1, id);
auto object = std::unique_ptr<T>(result);
if (id >= mObjects.size()) {
ASSERT(id == mObjects.size());
mObjects.emplace_back(std::move(object), 0);
} else {
ASSERT(mObjects[id].object == nullptr);
//* TODO(cwallez@chromium.org): investigate if overflows could cause bad things to happen
mObjects[id].serial++;
mObjects[id].object = std::move(object);
}
return &mObjects[id];
}
void Free(T* obj) {
FreeId(obj->id);
mObjects[obj->id].object = nullptr;
}
T* GetObject(uint32_t id) {
if (id >= mObjects.size()) {
return nullptr;
}
return mObjects[id].object.get();
}
uint32_t GetSerial(uint32_t id) {
if (id >= mObjects.size()) {
return 0;
}
return mObjects[id].serial;
}
private:
uint32_t GetNewId() {
if (mFreeIds.empty()) {
return mCurrentId ++;
}
uint32_t id = mFreeIds.back();
mFreeIds.pop_back();
return id;
}
void FreeId(uint32_t id) {
mFreeIds.push_back(id);
}
// 0 is an ID reserved to represent nullptr
uint32_t mCurrentId = 1;
std::vector<uint32_t> mFreeIds;
std::vector<ObjectAndSerial> mObjects;
Device* mDevice;
};
//* The client wire uses the global Dawn device to store its global data such as the serializer
//* and the object id allocators.
class Device : public ObjectBase, public ObjectIdProvider {
public:
Device(CommandSerializer* serializer)
: ObjectBase(this, 1, 1),
{% for type in by_category["object"] if not type.name.canonical_case() == "device" %}
{{type.name.camelCase()}}(this),
{% endfor %}
mSerializer(serializer) {
}
void* GetCmdSpace(size_t size) {
return mSerializer->GetCmdSpace(size);
}
{% for type in by_category["object"] if not type.name.canonical_case() == "device" %}
ObjectAllocator<{{type.name.CamelCase()}}> {{type.name.camelCase()}};
{% endfor %}
// Implementation of the ObjectIdProvider interface
{% for type in by_category["object"] %}
ObjectId GetId({{as_cType(type.name)}} object) const final {
return reinterpret_cast<{{as_wireType(type)}}>(object)->id;
}
ObjectId GetOptionalId({{as_cType(type.name)}} object) const final {
if (object == nullptr) {
return 0;
}
return GetId(object);
}
{% endfor %}
void HandleError(const char* message) {
if (errorCallback) {
errorCallback(message, errorUserdata);
}
}
dawnDeviceErrorCallback errorCallback = nullptr;
dawnCallbackUserdata errorUserdata;
private:
CommandSerializer* mSerializer = nullptr;
};
//* Implementation of the client API functions.
{% for type in by_category["object"] %}
{% set Type = type.name.CamelCase() %}
{% set cType = as_cType(type.name) %}
{% for method in type.methods %}
{% set Suffix = as_MethodSuffix(type.name, method.name) %}
{{as_cType(method.return_type.name)}} Client{{Suffix}}(
{{-cType}} cSelf
{%- for arg in method.arguments -%}
, {{as_annotated_cType(arg)}}
{%- endfor -%}
) {
auto self = reinterpret_cast<{{as_wireType(type)}}>(cSelf);
Device* device = self->device;
{{Suffix}}Cmd cmd;
//* Create the structure going on the wire on the stack and fill it with the value
//* arguments so it can compute its size.
cmd.self = cSelf;
//* For object creation, store the object ID the client will use for the result.
{% if method.return_type.category == "object" %}
auto* allocation = self->device->{{method.return_type.name.camelCase()}}.New();
{% if type.is_builder %}
//* We are in GetResult, so the callback that should be called is the
//* currently set one. Copy it over to the created object and prevent the
//* builder from calling the callback on destruction.
allocation->object->builderCallback = self->builderCallback;
self->builderCallback.canCall = false;
{% endif %}
cmd.resultId = allocation->object->id;
cmd.resultSerial = allocation->serial;
{% endif %}
{% for arg in method.arguments %}
cmd.{{as_varName(arg.name)}} = {{as_varName(arg.name)}};
{% endfor %}
//* Allocate space to send the command and copy the value args over.
size_t requiredSize = cmd.GetRequiredSize();
char* allocatedBuffer = static_cast<char*>(device->GetCmdSpace(requiredSize));
cmd.Serialize(allocatedBuffer, *device);
{% if method.return_type.category == "object" %}
return reinterpret_cast<{{as_cType(method.return_type.name)}}>(allocation->object.get());
{% endif %}
}
{% endfor %}
{% if type.is_builder %}
void Client{{as_MethodSuffix(type.name, Name("set error callback"))}}({{cType}} cSelf,
dawnBuilderErrorCallback callback,
dawnCallbackUserdata userdata1,
dawnCallbackUserdata userdata2) {
{{Type}}* self = reinterpret_cast<{{Type}}*>(cSelf);
self->builderCallback.callback = callback;
self->builderCallback.userdata1 = userdata1;
self->builderCallback.userdata2 = userdata2;
}
{% endif %}
{% if not type.name.canonical_case() == "device" %}
//* When an object's refcount reaches 0, notify the server side of it and delete it.
void Client{{as_MethodSuffix(type.name, Name("release"))}}({{cType}} cObj) {
{{Type}}* obj = reinterpret_cast<{{Type}}*>(cObj);
obj->refcount --;
if (obj->refcount > 0) {
return;
}
obj->builderCallback.Call(DAWN_BUILDER_ERROR_STATUS_UNKNOWN, "Unknown");
{{as_MethodSuffix(type.name, Name("destroy"))}}Cmd cmd;
cmd.objectId = obj->id;
auto allocCmd = static_cast<decltype(cmd)*>(obj->device->GetCmdSpace(sizeof(cmd)));
*allocCmd = cmd;
obj->device->{{type.name.camelCase()}}.Free(obj);
}
void Client{{as_MethodSuffix(type.name, Name("reference"))}}({{cType}} cObj) {
{{Type}}* obj = reinterpret_cast<{{Type}}*>(cObj);
obj->refcount ++;
}
{% endif %}
{% endfor %}
void ClientBufferMapReadAsync(dawnBuffer cBuffer, uint32_t start, uint32_t size, dawnBufferMapReadCallback callback, dawnCallbackUserdata userdata) {
Buffer* buffer = reinterpret_cast<Buffer*>(cBuffer);
uint32_t serial = buffer->requestSerial++;
ASSERT(buffer->requests.find(serial) == buffer->requests.end());
Buffer::MapRequestData request;
request.readCallback = callback;
request.userdata = userdata;
request.size = size;
request.isWrite = false;
buffer->requests[serial] = request;
BufferMapAsyncCmd cmd;
cmd.bufferId = buffer->id;
cmd.requestSerial = serial;
cmd.start = start;
cmd.size = size;
cmd.isWrite = false;
auto allocCmd = static_cast<decltype(cmd)*>(buffer->device->GetCmdSpace(sizeof(cmd)));
*allocCmd = cmd;
}
void ClientBufferMapWriteAsync(dawnBuffer cBuffer, uint32_t start, uint32_t size, dawnBufferMapWriteCallback callback, dawnCallbackUserdata userdata) {
Buffer* buffer = reinterpret_cast<Buffer*>(cBuffer);
uint32_t serial = buffer->requestSerial++;
ASSERT(buffer->requests.find(serial) == buffer->requests.end());
Buffer::MapRequestData request;
request.writeCallback = callback;
request.userdata = userdata;
request.size = size;
request.isWrite = true;
buffer->requests[serial] = request;
BufferMapAsyncCmd cmd;
cmd.bufferId = buffer->id;
cmd.requestSerial = serial;
cmd.start = start;
cmd.size = size;
cmd.isWrite = true;
auto allocCmd = static_cast<decltype(cmd)*>(buffer->device->GetCmdSpace(sizeof(cmd)));
*allocCmd = cmd;
}
void ProxyClientBufferUnmap(dawnBuffer cBuffer) {
Buffer* buffer = reinterpret_cast<Buffer*>(cBuffer);
//* Invalidate the local pointer, and cancel all other in-flight requests that would turn into
//* errors anyway (you can't double map). This prevents race when the following happens, where
//* the application code would have unmapped a buffer but still receive a callback:
//* - Client -> Server: MapRequest1, Unmap, MapRequest2
//* - Server -> Client: Result of MapRequest1
//* - Unmap locally on the client
//* - Server -> Client: Result of MapRequest2
if (buffer->mappedData) {
// If the buffer was mapped for writing, send the update to the data to the server
if (buffer->isWriteMapped) {
BufferUpdateMappedDataCmd cmd;
cmd.bufferId = buffer->id;
cmd.dataLength = static_cast<uint32_t>(buffer->mappedDataSize);
auto allocCmd = static_cast<decltype(cmd)*>(buffer->device->GetCmdSpace(sizeof(cmd)));
*allocCmd = cmd;
void* dataAlloc = buffer->device->GetCmdSpace(cmd.dataLength);
memcpy(dataAlloc, buffer->mappedData, cmd.dataLength);
}
free(buffer->mappedData);
buffer->mappedData = nullptr;
}
buffer->ClearMapRequests(DAWN_BUFFER_MAP_ASYNC_STATUS_UNKNOWN);
ClientBufferUnmap(cBuffer);
}
void ClientDeviceReference(dawnDevice) {
}
void ClientDeviceRelease(dawnDevice) {
}
void ClientDeviceSetErrorCallback(dawnDevice cSelf, dawnDeviceErrorCallback callback, dawnCallbackUserdata userdata) {
Device* self = reinterpret_cast<Device*>(cSelf);
self->errorCallback = callback;
self->errorUserdata = userdata;
}
// Some commands don't have a custom wire format, but need to be handled manually to update
// some client-side state tracking. For these we have two functions:
// - An autogenerated Client{{suffix}} method that sends the command on the wire
// - A manual ProxyClient{{suffix}} method that will be inserted in the proctable instead of
// the autogenerated one, and that will have to call Client{{suffix}}
{% set proxied_commands = ["BufferUnmap"] %}
dawnProcTable GetProcs() {
dawnProcTable table;
{% for type in by_category["object"] %}
{% for method in native_methods(type) %}
{% set suffix = as_MethodSuffix(type.name, method.name) %}
{% if suffix in proxied_commands %}
table.{{as_varName(type.name, method.name)}} = ProxyClient{{suffix}};
{% else %}
table.{{as_varName(type.name, method.name)}} = Client{{suffix}};
{% endif %}
{% endfor %}
{% endfor %}
return table;
}
class Client : public CommandHandler {
public:
Client(Device* device) : mDevice(device) {
}
const char* HandleCommands(const char* commands, size_t size) override {
while (size >= sizeof(ReturnWireCmd)) {
ReturnWireCmd cmdId = *reinterpret_cast<const ReturnWireCmd*>(commands);
bool success = false;
switch (cmdId) {
case ReturnWireCmd::DeviceErrorCallback:
success = HandleDeviceErrorCallbackCmd(&commands, &size);
break;
{% for type in by_category["object"] if type.is_builder %}
case ReturnWireCmd::{{type.name.CamelCase()}}ErrorCallback:
success = Handle{{type.name.CamelCase()}}ErrorCallbackCmd(&commands, &size);
break;
{% endfor %}
case ReturnWireCmd::BufferMapReadAsyncCallback:
success = HandleBufferMapReadAsyncCallback(&commands, &size);
break;
case ReturnWireCmd::BufferMapWriteAsyncCallback:
success = HandleBufferMapWriteAsyncCallback(&commands, &size);
break;
default:
success = false;
}
if (!success) {
return nullptr;
}
}
if (size != 0) {
return nullptr;
}
return commands;
}
private:
Device* mDevice = nullptr;
//* Helper function for the getting of the command data in command handlers.
//* Checks there is enough data left, updates the buffer / size and returns
//* the command (or nullptr for an error).
template <typename T>
static const T* GetData(const char** buffer, size_t* size, size_t count) {
// TODO(cwallez@chromium.org): Check for overflow
size_t totalSize = count * sizeof(T);
if (*size < totalSize) {
return nullptr;
}
const T* data = reinterpret_cast<const T*>(*buffer);
*buffer += totalSize;
*size -= totalSize;
return data;
}
template <typename T>
static const T* GetCommand(const char** commands, size_t* size) {
return GetData<T>(commands, size, 1);
}
bool HandleDeviceErrorCallbackCmd(const char** commands, size_t* size) {
const auto* cmd = GetCommand<ReturnDeviceErrorCallbackCmd>(commands, size);
if (cmd == nullptr) {
return false;
}
const char* message = GetData<char>(commands, size, cmd->messageStrlen + 1);
if (message == nullptr || message[cmd->messageStrlen] != '\0') {
return false;
}
mDevice->HandleError(message);
return true;
}
{% for type in by_category["object"] if type.is_builder %}
{% set Type = type.name.CamelCase() %}
bool Handle{{Type}}ErrorCallbackCmd(const char** commands, size_t* size) {
const auto* cmd = GetCommand<Return{{Type}}ErrorCallbackCmd>(commands, size);
if (cmd == nullptr) {
return false;
}
const char* message = GetData<char>(commands, size, cmd->messageStrlen + 1);
if (message == nullptr || message[cmd->messageStrlen] != '\0') {
return false;
}
auto* builtObject = mDevice->{{type.built_type.name.camelCase()}}.GetObject(cmd->builtObjectId);
uint32_t objectSerial = mDevice->{{type.built_type.name.camelCase()}}.GetSerial(cmd->builtObjectId);
//* The object might have been deleted or a new object created with the same ID.
if (builtObject == nullptr || objectSerial != cmd->builtObjectSerial) {
return true;
}
bool called = builtObject->builderCallback.Call(static_cast<dawnBuilderErrorStatus>(cmd->status), message);
// Unhandled builder errors are forwarded to the device
if (!called && cmd->status != DAWN_BUILDER_ERROR_STATUS_SUCCESS && cmd->status != DAWN_BUILDER_ERROR_STATUS_UNKNOWN) {
mDevice->HandleError(("Unhandled builder error: " + std::string(message)).c_str());
}
return true;
}
{% endfor %}
bool HandleBufferMapReadAsyncCallback(const char** commands, size_t* size) {
const auto* cmd = GetCommand<ReturnBufferMapReadAsyncCallbackCmd>(commands, size);
if (cmd == nullptr) {
return false;
}
//* Unconditionnally get the data from the buffer so that the correct amount of data is
//* consumed from the buffer, even when we ignore the command and early out.
const char* requestData = nullptr;
if (cmd->status == DAWN_BUFFER_MAP_ASYNC_STATUS_SUCCESS) {
requestData = GetData<char>(commands, size, cmd->dataLength);
if (requestData == nullptr) {
return false;
}
}
auto* buffer = mDevice->buffer.GetObject(cmd->bufferId);
uint32_t bufferSerial = mDevice->buffer.GetSerial(cmd->bufferId);
//* The buffer might have been deleted or recreated so this isn't an error.
if (buffer == nullptr || bufferSerial != cmd->bufferSerial) {
return true;
}
//* The requests can have been deleted via an Unmap so this isn't an error.
auto requestIt = buffer->requests.find(cmd->requestSerial);
if (requestIt == buffer->requests.end()) {
return true;
}
//* It is an error for the server to call the read callback when we asked for a map write
if (requestIt->second.isWrite) {
return false;
}
auto request = requestIt->second;
//* Delete the request before calling the callback otherwise the callback could be fired a
//* second time. If, for example, buffer.Unmap() is called inside the callback.
buffer->requests.erase(requestIt);
//* On success, we copy the data locally because the IPC buffer isn't valid outside of this function
if (cmd->status == DAWN_BUFFER_MAP_ASYNC_STATUS_SUCCESS) {
//* The server didn't send the right amount of data, this is an error and could cause
//* the application to crash if we did call the callback.
if (request.size != cmd->dataLength) {
return false;
}
ASSERT(requestData != nullptr);
if (buffer->mappedData != nullptr) {
return false;
}
buffer->isWriteMapped = false;
buffer->mappedDataSize = request.size;
buffer->mappedData = malloc(request.size);
memcpy(buffer->mappedData, requestData, request.size);
request.readCallback(static_cast<dawnBufferMapAsyncStatus>(cmd->status), buffer->mappedData, request.userdata);
} else {
request.readCallback(static_cast<dawnBufferMapAsyncStatus>(cmd->status), nullptr, request.userdata);
}
return true;
}
bool HandleBufferMapWriteAsyncCallback(const char** commands, size_t* size) {
const auto* cmd = GetCommand<ReturnBufferMapWriteAsyncCallbackCmd>(commands, size);
if (cmd == nullptr) {
return false;
}
auto* buffer = mDevice->buffer.GetObject(cmd->bufferId);
uint32_t bufferSerial = mDevice->buffer.GetSerial(cmd->bufferId);
//* The buffer might have been deleted or recreated so this isn't an error.
if (buffer == nullptr || bufferSerial != cmd->bufferSerial) {
return true;
}
//* The requests can have been deleted via an Unmap so this isn't an error.
auto requestIt = buffer->requests.find(cmd->requestSerial);
if (requestIt == buffer->requests.end()) {
return true;
}
//* It is an error for the server to call the write callback when we asked for a map read
if (!requestIt->second.isWrite) {
return false;
}
auto request = requestIt->second;
//* Delete the request before calling the callback otherwise the callback could be fired a second time. If, for example, buffer.Unmap() is called inside the callback.
buffer->requests.erase(requestIt);
//* On success, we copy the data locally because the IPC buffer isn't valid outside of this function
if (cmd->status == DAWN_BUFFER_MAP_ASYNC_STATUS_SUCCESS) {
if (buffer->mappedData != nullptr) {
return false;
}
buffer->isWriteMapped = true;
buffer->mappedDataSize = request.size;
buffer->mappedData = malloc(request.size);
memset(buffer->mappedData, 0, request.size);
request.writeCallback(static_cast<dawnBufferMapAsyncStatus>(cmd->status), buffer->mappedData, request.userdata);
} else {
request.writeCallback(static_cast<dawnBufferMapAsyncStatus>(cmd->status), nullptr, request.userdata);
}
return true;
}
};
}
CommandHandler* NewClientDevice(dawnProcTable* procs, dawnDevice* device, CommandSerializer* serializer) {
auto clientDevice = new client::Device(serializer);
*device = reinterpret_cast<dawnDeviceImpl*>(clientDevice);
*procs = client::GetProcs();
return new client::Client(clientDevice);
}
} // namespace dawn_wire