1 // Copyright 2018 The Fuchsia Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5
6 #include <limits>
7 #include <stdalign.h>
8 #include <stdint.h>
9 #include <stdlib.h>
10
11 #include <lib/fidl/coding.h>
12
13 #ifdef __Fuchsia__
14
15 #include <lib/fidl/internal.h>
16 #include <zircon/assert.h>
17 #include <zircon/compiler.h>
18 #include <zircon/syscalls.h>
19
20 #include "buffer_walker.h"
21
22 namespace {
23
24 class FidlHandleCloser final : public fidl::internal::BufferWalker<FidlHandleCloser, true, true> {
25 typedef fidl::internal::BufferWalker<FidlHandleCloser, true, true> Super;
26
27 public:
FidlHandleCloser(const fidl_type_t * type,void * bytes,uint32_t num_bytes,const char ** out_error_msg)28 FidlHandleCloser(const fidl_type_t* type, void* bytes, uint32_t num_bytes,
29 const char** out_error_msg)
30 : Super(type), bytes_(static_cast<uint8_t*>(bytes)), num_bytes_(num_bytes),
31 out_error_msg_(out_error_msg) {}
32
Walk()33 void Walk() {
34 Super::Walk();
35 }
36
bytes() const37 uint8_t* bytes() const { return bytes_; }
num_bytes() const38 uint32_t num_bytes() const { return num_bytes_; }
num_handles() const39 uint32_t num_handles() const { return std::numeric_limits<uint32_t>::max(); }
40
ValidateOutOfLineStorageClaim(const void * a,void * b)41 bool ValidateOutOfLineStorageClaim(const void* a, void* b) {
42 return true;
43 }
44
UnclaimedHandle(zx_handle_t * out_handle)45 void UnclaimedHandle(zx_handle_t* out_handle) {
46 // This will never happen since we are returning numeric_limits::max() in num_handles.
47 // We want to claim (close) all the handles.
48 ZX_DEBUG_ASSERT(false);
49 }
50
ClaimedHandle(zx_handle_t * out_handle,uint32_t idx)51 void ClaimedHandle(zx_handle_t* out_handle, uint32_t idx) {
52 if (*out_handle != ZX_HANDLE_INVALID) {
53 zx_handle_close(*out_handle);
54 }
55 *out_handle = ZX_HANDLE_INVALID;
56 }
57
58 template <class T>
UpdatePointer(T * const * p,T * v)59 void UpdatePointer(T* const* p, T* v) {}
60
GetPointerState(const void * ptr) const61 PointerState GetPointerState(const void* ptr) const {
62 return *static_cast<const uintptr_t*>(ptr) == 0
63 ? PointerState::ABSENT
64 : PointerState::PRESENT;
65 }
66
GetHandleState(zx_handle_t p) const67 HandleState GetHandleState(zx_handle_t p) const {
68 // Treat all handles as present to keep the buffer walker going.
69 return HandleState::PRESENT;
70 }
71
SetError(const char * error_msg)72 void SetError(const char* error_msg) {
73 status_ = ZX_ERR_INVALID_ARGS;
74 if (out_error_msg_ != nullptr) {
75 *out_error_msg_ = error_msg;
76 }
77 }
78
status() const79 zx_status_t status() const { return status_; }
80
81 private:
82 // Message state passed in to the constructor.
83 uint8_t* const bytes_;
84 const uint32_t num_bytes_;
85 const char** const out_error_msg_;
86 zx_status_t status_ = ZX_OK;
87 };
88
89 } // namespace
90
91 #endif // __Fuchsia__
92
fidl_close_handles(const fidl_type_t * type,void * bytes,uint32_t num_bytes,const char ** out_error_msg)93 zx_status_t fidl_close_handles(const fidl_type_t* type, void* bytes, uint32_t num_bytes,
94 const char** out_error_msg) {
95 #if __Fuchsia__
96 FidlHandleCloser handle_closer(type, bytes, num_bytes, out_error_msg);
97 handle_closer.Walk();
98 return handle_closer.status();
99 #else
100 return ZX_OK; // there can't be any handles on the host
101 #endif
102 }
103
fidl_close_handles_msg(const fidl_type_t * type,const fidl_msg_t * msg,const char ** out_error_msg)104 zx_status_t fidl_close_handles_msg(const fidl_type_t* type, const fidl_msg_t* msg,
105 const char** out_error_msg) {
106 return fidl_close_handles(type, msg->bytes, msg->num_bytes, out_error_msg);
107 }
108
109