1 files changed, 259 insertions, 0 deletions

diff --git a/src/core/hle/ipc_helpers.h b/src/core/hle/ipc_helpers.h
new file mode 100644
index 000000000..6089c39c7
--- /dev/null
+++ b/src/core/hle/ipc_helpers.h
@@ -0,0 +1,259 @@
+// Copyright 2016 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+#include "core/hle/ipc.h"
+#include "core/hle/kernel/kernel.h"
+
+namespace IPC {
+
+class RequestHelperBase {
+protected:
+    u32* cmdbuf;
+    ptrdiff_t index = 1;
+    Header header;
+
+public:
+    RequestHelperBase(u32* command_buffer, Header command_header)
+        : cmdbuf(command_buffer), header(command_header) {}
+
+    /// Returns the total size of the request in words
+    size_t TotalSize() const {
+        return 1 /* command header */ + header.normal_params_size + header.translate_params_size;
+    }
+
+    void ValidateHeader() {
+        DEBUG_ASSERT_MSG(index == TotalSize(), "Operations do not match the header (cmd 0x%x)",
+                         header.raw);
+    }
+};
+
+class RequestBuilder : public RequestHelperBase {
+public:
+    RequestBuilder(u32* command_buffer, Header command_header)
+        : RequestHelperBase(command_buffer, command_header) {
+        cmdbuf[0] = header.raw;
+    }
+    explicit RequestBuilder(u32* command_buffer, u32 command_header)
+        : RequestBuilder(command_buffer, Header{command_header}) {}
+    RequestBuilder(u32* command_buffer, u16 command_id, unsigned normal_params_size,
+                   unsigned translate_params_size)
+        : RequestBuilder(command_buffer,
+                         MakeHeader(command_id, normal_params_size, translate_params_size)) {}
+
+    // Validate on destruction, as there shouldn't be any case where we don't want it
+    ~RequestBuilder() {
+        ValidateHeader();
+    }
+
+    template <typename T>
+    void Push(T value);
+
+    template <>
+    void Push(u32);
+
+    template <typename First, class... Other>
+    void Push(First first_value, const Other&... other_values) {
+        Push(first_value);
+        Push(other_values...);
+    }
+
+    /**
+     * @brief Copies the content of the given trivially copyable class to the buffer as a normal
+     * param
+     * @note: The input class must be correctly packed/padded to fit hardware layout.
+     */
+    template <typename T>
+    void PushRaw(const T& value) {
+        static_assert(std::is_trivially_copyable<T>(), "Raw types should be trivially copyable");
+        std::memcpy(cmdbuf + index, &value, sizeof(T));
+        index += (sizeof(T) + 3) / 4; // round up to word length
+    }
+
+    // TODO : ensure that translate params are added after all regular params
+    template <typename... H>
+    void PushCopyHandles(H... handles) {
+        Push(CopyHandleDesc(sizeof...(H)));
+        Push(static_cast<Kernel::Handle>(handles)...);
+    }
+
+    template <typename... H>
+    void PushMoveHandles(H... handles) {
+        Push(MoveHandleDesc(sizeof...(H)));
+        Push(static_cast<Kernel::Handle>(handles)...);
+    }
+
+    void PushCurrentPIDHandle() {
+        Push(CallingPidDesc());
+        Push<u32>(0);
+    }
+
+    void PushStaticBuffer(VAddr buffer_vaddr, u32 size, u8 buffer_id) {
+        Push(StaticBufferDesc(size, buffer_id));
+        Push(buffer_vaddr);
+    }
+
+    void PushMappedBuffer(VAddr buffer_vaddr, u32 size, MappedBufferPermissions perms) {
+        Push(MappedBufferDesc(size, perms));
+        Push(buffer_vaddr);
+    }
+};
+
+class RequestParser : public RequestHelperBase {
+public:
+    RequestParser(u32* command_buffer, Header command_header)
+        : RequestHelperBase(command_buffer, command_header) {}
+    explicit RequestParser(u32* command_buffer, u32 command_header)
+        : RequestParser(command_buffer, Header{command_header}) {}
+    RequestParser(u32* command_buffer, u16 command_id, unsigned normal_params_size,
+                  unsigned translate_params_size)
+        : RequestParser(command_buffer,
+                        MakeHeader(command_id, normal_params_size, translate_params_size)) {}
+
+    RequestBuilder MakeBuilder(u32 normal_params_size, u32 translate_params_size,
+                               bool validateHeader = true) {
+        if (validateHeader)
+            ValidateHeader();
+        Header builderHeader{
+            MakeHeader(header.command_id, normal_params_size, translate_params_size)};
+        return {cmdbuf, builderHeader};
+    }
+
+    template <typename T>
+    T Pop();
+
+    template <>
+    u32 Pop<u32>();
+
+    template <typename T>
+    void Pop(T& value) {
+        value = Pop<T>();
+    }
+
+    template <typename First, class... Other>
+    void Pop(First& first_value, Other&... other_values) {
+        first_value = Pop<First>();
+        Pop(other_values...);
+    }
+
+    Kernel::Handle PopHandle() {
+        const u32 handle_descriptor = Pop<u32>();
+        DEBUG_ASSERT_MSG(IsHandleDescriptor(handle_descriptor),
+                         "Tried to pop handle(s) but the descriptor is not a handle descriptor");
+        DEBUG_ASSERT_MSG(HandleNumberFromDesc(handle_descriptor) == 1,
+                         "Descriptor indicates that there isn't exactly one handle");
+        return Pop<Kernel::Handle>();
+    }
+
+    template <typename... H>
+    void PopHandles(H&... handles) {
+        const u32 handle_descriptor = Pop<u32>();
+        const int handles_number = sizeof...(H);
+        DEBUG_ASSERT_MSG(IsHandleDescriptor(handle_descriptor),
+                         "Tried to pop handle(s) but the descriptor is not a handle descriptor");
+        DEBUG_ASSERT_MSG(handles_number == HandleNumberFromDesc(handle_descriptor),
+                         "Number of handles doesn't match the descriptor");
+        Pop(static_cast<Kernel::Handle&>(handles)...);
+    }
+
+    /**
+     * @brief Pops the static buffer vaddr
+     * @return                  The virtual address of the buffer
+     * @param[out] data_size    If non-null, the pointed value will be set to the size of the data
+     * @param[out] useStaticBuffersToGetVaddr Indicates if we should read the vaddr from the static
+     * buffers (which is the correct thing to do, but no service presently implement it) instead of
+     * using the same value as the process who sent the request
+     * given by the source process
+     *
+     * Static buffers must be set up before any IPC request using those is sent.
+     * It is the duty of the process (usually services) to allocate and set up the receiving static
+     * buffer information
+     * Please note that the setup uses virtual addresses.
+     */
+    VAddr PopStaticBuffer(size_t* data_size = nullptr, bool useStaticBuffersToGetVaddr = false) {
+        const u32 sbuffer_descriptor = Pop<u32>();
+        StaticBufferDescInfo bufferInfo{sbuffer_descriptor};
+        if (data_size != nullptr)
+            *data_size = bufferInfo.size;
+        if (!useStaticBuffersToGetVaddr)
+            return Pop<VAddr>();
+        else {
+            ASSERT_MSG(0, "remove the assert if multiprocess/IPC translation are implemented.");
+            // The buffer has already been copied to the static buffer by the kernel during
+            // translation
+            Pop<VAddr>(); // Pop the calling process buffer address
+                          // and get the vaddr from the static buffers
+            return cmdbuf[(0x100 >> 2) + bufferInfo.buffer_id * 2 + 1];
+        }
+    }
+
+    /**
+     * @brief Pops the mapped buffer vaddr
+     * @return                  The virtual address of the buffer
+     * @param[out] data_size    If non-null, the pointed value will be set to the size of the data
+     * given by the source process
+     * @param[out] buffer_perms If non-null, the pointed value will be set to the permissions of the
+     * buffer
+     */
+    VAddr PopMappedBuffer(size_t* data_size = nullptr,
+                          MappedBufferPermissions* buffer_perms = nullptr) {
+        const u32 sbuffer_descriptor = Pop<u32>();
+        MappedBufferDescInfo bufferInfo{sbuffer_descriptor};
+        if (data_size != nullptr)
+            *data_size = bufferInfo.size;
+        if (buffer_perms != nullptr)
+            *buffer_perms = bufferInfo.perms;
+        return Pop<VAddr>();
+    }
+
+    /**
+     * @brief Reads the next normal parameters as a struct, by copying it
+     * @note: The output class must be correctly packed/padded to fit hardware layout.
+     */
+    template <typename T>
+    void PopRaw(T& value) {
+        static_assert(std::is_trivially_copyable<T>(), "Raw types should be trivially copyable");
+        std::memcpy(&value, cmdbuf + index, sizeof(T));
+        index += (sizeof(T) + 3) / 4; // round up to word length
+    }
+};
+
+/// Pop ///
+
+template <>
+inline u32 RequestParser::Pop<u32>() {
+    return cmdbuf[index++];
+}
+
+template <>
+inline u64 RequestParser::Pop<u64>() {
+    const u64 lsw = Pop<u32>();
+    const u64 msw = Pop<u32>();
+    return msw << 32 | lsw;
+}
+
+template <>
+inline ResultCode RequestParser::Pop<ResultCode>() {
+    return ResultCode{Pop<u32>()};
+}
+
+/// Push ///
+
+template <>
+inline void RequestBuilder::Push<u32>(u32 value) {
+    cmdbuf[index++] = value;
+}
+
+template <>
+inline void RequestBuilder::Push<u64>(u64 value) {
+    Push(static_cast<u32>(value));
+    Push(static_cast<u32>(value >> 32));
+}
+
+template <>
+inline void RequestBuilder::Push<ResultCode>(ResultCode value) {
+    Push(value.raw);
+}
+
+} // namespace IPC