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build: fix various shared library build issues
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Node.js unofficially supports a shared library variant where the
main node executable is a thin wrapper around node.dll/libnode.so.
The key benefit of this is to support embedding Node.js in other
applications.

Since Node.js 12 there have been a number of issues preventing the
shared library build from working correctly, primarily on Windows:

* A number of functions used executables such as `mksnapshot` are
    not exported from `libnode.dll` using a `NODE_EXTERN` attribute
* A dependency on the `Winmm` system library is missing
* Incorrect defines on executable targets leads to `node.exe`
    claiming to export a number of functions that are actually in
    `libnode.dll`
* Because `node.exe` attempts to export symbols, `node.lib` gets
    generated causing native extensions to try to link against
    `node.exe` not `libnode.dll`.
* Similarly, because `node.dll` was renamed to `libnode.dll`,
    native extensions don't know to look for `libnode.lib` rather
    than `node.lib`.
* On macOS an RPATH is added to find `libnode.dylib` relative to
    `node` in the same folder. This works fine from the
    `out/Release` folder but not from an installed prefix, where
    `node` will be in `bin/` and `libnode.dylib` will be in `lib/`.
* Similarly on Linux, no RPATH is added so LD_LIBRARY_PATH needs
    setting correctly for `bin/node` to find `lib/libnode.so`.

For the `libnode.lib` vs `node.lib` issue there are two possible
options:

1. Ensure `node.lib` from `node.exe` does not get generated, and
    instead copy `libnode.lib` to `node.lib`. This means addons
    compiled when referencing the correct `node.lib` file will
    correctly depend on `libnode.dll`. The down side is that
    native addons compiled with stock Node.js will still try to
    resolve symbols against node.exe rather than libnode.dll.
2. After building `libnode.dll`, dump the exports using `dumpbin`,
    and process this to generate a `node.def` file to be linked into
    `node.exe` with the `/DEF:node.def` flag. The export entries
    in `node.def` will all read
    ```
    my_symbol=libnode.my_symbol
    ```
    so that `node.exe` will redirect all exported symbols back to
    `libnode.dll`. This has the benefit that addons compiled with
    stock Node.js will load correctly into `node.exe` from a shared
    library build, but means that every embedding executable also
    needs to perform this same trick.

I went with the first option as it is the cleaner of the two
solutions in my opinion. Projects wishing to generate a shared
library variant of Node.js can now, for example,
```
.\vcbuild dll package vs
```
to generate a full node installation including `libnode.dll`,
`Release\node.lib`, and all the necessary headers. Native addons
can then be built against the shared library build easily by
specifying the correct `nodedir` option.

For example
```
>npx node-gyp configure --nodedir
   C:\Users\User\node\Release\node-v18.0.0-win-x64
...
>npx node-gyp build
...
>dumpbin /dependents build\Release\binding.node
Microsoft (R) COFF/PE Dumper Version 14.29.30136.0
Copyright (C) Microsoft Corporation.  All rights reserved.

Dump of file build\Release\binding.node

File Type: DLL

  Image has the following dependencies:

    KERNEL32.dll
    libnode.dll
    VCRUNTIME140.dll
    api-ms-win-crt-string-l1-1-0.dll
    api-ms-win-crt-stdio-l1-1-0.dll
    api-ms-win-crt-runtime-l1-1-0.dll
...
```

PR-URL: #41850
Reviewed-By: Michael Dawson <midawson@redhat.com>
Reviewed-By: Beth Griggs <bgriggs@redhat.com>
Reviewed-By: Richard Lau <rlau@redhat.com>
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lux01 authored and RafaelGSS committed May 10, 2022
1 parent 840e61e commit 0eb32ed
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55 changes: 54 additions & 1 deletion node.gyp
Original file line number Diff line number Diff line change
Expand Up @@ -196,6 +196,16 @@
'dependencies': [ 'node_aix_shared' ],
}, {
'dependencies': [ '<(node_lib_target_name)' ],
'conditions': [
['OS=="win" and node_shared=="true"', {
'dependencies': ['generate_node_def'],
'msvs_settings': {
'VCLinkerTool': {
'ModuleDefinitionFile': '<(PRODUCT_DIR)/<(node_core_target_name).def',
},
},
}],
],
}],
[ 'node_intermediate_lib_type=="static_library" and node_shared=="false"', {
'xcode_settings': {
Expand Down Expand Up @@ -235,8 +245,15 @@
}],
[ 'node_shared=="true"', {
'xcode_settings': {
'OTHER_LDFLAGS': [ '-Wl,-rpath,@loader_path', ],
'OTHER_LDFLAGS': [ '-Wl,-rpath,@loader_path', '-Wl,-rpath,@loader_path/../lib'],
},
'conditions': [
['OS=="linux"', {
'ldflags': [
'-Wl,-rpath,\\$$ORIGIN/../lib'
],
}],
],
}],
[ 'enable_lto=="true"', {
'xcode_settings': {
Expand Down Expand Up @@ -749,6 +766,7 @@
'libraries': [
'Dbghelp',
'Psapi',
'Winmm',
'Ws2_32',
],
}],
Expand Down Expand Up @@ -1502,5 +1520,40 @@
},
]
}], # end aix section
['OS=="win" and node_shared=="true"', {
'targets': [
{
'target_name': 'gen_node_def',
'type': 'executable',
'sources': [
'tools/gen_node_def.cc'
],
},
{
'target_name': 'generate_node_def',
'dependencies': [
'gen_node_def',
'<(node_lib_target_name)',
],
'type': 'none',
'actions': [
{
'action_name': 'generate_node_def_action',
'inputs': [
'<(PRODUCT_DIR)/<(node_lib_target_name).dll'
],
'outputs': [
'<(PRODUCT_DIR)/<(node_core_target_name).def',
],
'action': [
'<(PRODUCT_DIR)/gen_node_def.exe',
'<@(_inputs)',
'<@(_outputs)',
],
},
],
},
],
}], # end win section
], # end conditions block
}
15 changes: 14 additions & 1 deletion node.gypi
Original file line number Diff line number Diff line change
Expand Up @@ -29,7 +29,7 @@
[ 'clang==1', {
'cflags': [ '-Werror=undefined-inline', ]
}],
[ 'node_shared=="false" and "<(_type)"=="executable"', {
[ '"<(_type)"=="executable"', {
'msvs_settings': {
'VCManifestTool': {
'EmbedManifest': 'true',
Expand All @@ -41,6 +41,19 @@
'defines': [
'NODE_SHARED_MODE',
],
'conditions': [
['"<(_type)"=="executable"', {
'defines': [
'USING_UV_SHARED',
'USING_V8_SHARED',
'BUILDING_NODE_EXTENSION'
],
'defines!': [
'BUILDING_V8_SHARED=1',
'BUILDING_UV_SHARED=1'
]
}],
],
}],
[ 'OS=="win"', {
'defines!': [
Expand Down
6 changes: 3 additions & 3 deletions src/debug_utils.h
Original file line number Diff line number Diff line change
Expand Up @@ -35,7 +35,7 @@ template <typename... Args>
inline std::string SPrintF(const char* format, Args&&... args);
template <typename... Args>
inline void FPrintF(FILE* file, const char* format, Args&&... args);
void FWrite(FILE* file, const std::string& str);
void NODE_EXTERN_PRIVATE FWrite(FILE* file, const std::string& str);

// Listing the AsyncWrap provider types first enables us to cast directly
// from a provider type to a debug category.
Expand All @@ -57,7 +57,7 @@ enum class DebugCategory {
CATEGORY_COUNT
};

class EnabledDebugList {
class NODE_EXTERN_PRIVATE EnabledDebugList {
public:
bool enabled(DebugCategory category) const {
DCHECK_GE(static_cast<int>(category), 0);
Expand Down Expand Up @@ -168,7 +168,7 @@ void CheckedUvLoopClose(uv_loop_t* loop);
void PrintLibuvHandleInformation(uv_loop_t* loop, FILE* stream);

namespace per_process {
extern EnabledDebugList enabled_debug_list;
extern NODE_EXTERN_PRIVATE EnabledDebugList enabled_debug_list;

template <typename... Args>
inline void FORCE_INLINE Debug(DebugCategory cat,
Expand Down
2 changes: 1 addition & 1 deletion src/env.h
Original file line number Diff line number Diff line change
Expand Up @@ -558,7 +558,7 @@ class Environment;
struct AllocatedBuffer;

typedef size_t SnapshotIndex;
class IsolateData : public MemoryRetainer {
class NODE_EXTERN_PRIVATE IsolateData : public MemoryRetainer {
public:
IsolateData(v8::Isolate* isolate,
uv_loop_t* event_loop,
Expand Down
10 changes: 10 additions & 0 deletions src/node.h
Original file line number Diff line number Diff line change
Expand Up @@ -32,6 +32,16 @@
# define NODE_EXTERN __attribute__((visibility("default")))
#endif

// Declarations annotated with NODE_EXTERN_PRIVATE do not form part of
// the public API. They are implementation details that can and will
// change between releases, even in semver patch releases. Do not use
// any such symbol in external code.
#ifdef NODE_SHARED_MODE
#define NODE_EXTERN_PRIVATE NODE_EXTERN
#else
#define NODE_EXTERN_PRIVATE
#endif

#ifdef BUILDING_NODE_EXTENSION
# undef BUILDING_V8_SHARED
# undef BUILDING_UV_SHARED
Expand Down
15 changes: 8 additions & 7 deletions src/node_internals.h
Original file line number Diff line number Diff line change
Expand Up @@ -320,13 +320,14 @@ enum InitializationSettingsFlags : uint64_t {
};

// TODO(codebytere): eventually document and expose to embedders.
InitializationResult InitializeOncePerProcess(int argc, char** argv);
InitializationResult InitializeOncePerProcess(
int argc,
char** argv,
InitializationSettingsFlags flags,
ProcessFlags::Flags process_flags = ProcessFlags::kNoFlags);
void TearDownOncePerProcess();
InitializationResult NODE_EXTERN_PRIVATE InitializeOncePerProcess(int argc,
char** argv);
InitializationResult NODE_EXTERN_PRIVATE InitializeOncePerProcess(
int argc,
char** argv,
InitializationSettingsFlags flags,
ProcessFlags::Flags process_flags = ProcessFlags::kNoFlags);
void NODE_EXTERN_PRIVATE TearDownOncePerProcess();
void SetIsolateErrorHandlers(v8::Isolate* isolate, const IsolateSettings& s);
void SetIsolateMiscHandlers(v8::Isolate* isolate, const IsolateSettings& s);
void SetIsolateCreateParamsForNode(v8::Isolate::CreateParams* params);
Expand Down
2 changes: 1 addition & 1 deletion src/node_native_module.h
Original file line number Diff line number Diff line change
Expand Up @@ -29,7 +29,7 @@ using NativeModuleCacheMap =
// This class should not depend on any Environment, or depend on access to
// the its own singleton - that should be encapsulated in NativeModuleEnv
// instead.
class NativeModuleLoader {
class NODE_EXTERN_PRIVATE NativeModuleLoader {
public:
NativeModuleLoader(const NativeModuleLoader&) = delete;
NativeModuleLoader& operator=(const NativeModuleLoader&) = delete;
Expand Down
2 changes: 1 addition & 1 deletion src/node_options.h
Original file line number Diff line number Diff line change
Expand Up @@ -491,7 +491,7 @@ void Parse(
namespace per_process {

extern Mutex cli_options_mutex;
extern std::shared_ptr<PerProcessOptions> cli_options;
extern NODE_EXTERN_PRIVATE std::shared_ptr<PerProcessOptions> cli_options;

} // namespace per_process

Expand Down
2 changes: 1 addition & 1 deletion src/node_snapshot_builder.h
Original file line number Diff line number Diff line change
Expand Up @@ -13,7 +13,7 @@ namespace node {
class ExternalReferenceRegistry;
struct SnapshotData;

class SnapshotBuilder {
class NODE_EXTERN_PRIVATE SnapshotBuilder {
public:
static std::string Generate(const std::vector<std::string> args,
const std::vector<std::string> exec_args);
Expand Down
6 changes: 4 additions & 2 deletions src/util.h
Original file line number Diff line number Diff line change
Expand Up @@ -26,6 +26,8 @@

#include "v8.h"

#include "node.h"

#include <climits>
#include <cstddef>
#include <cstdio>
Expand Down Expand Up @@ -110,8 +112,8 @@ struct AssertionInfo {
const char* message;
const char* function;
};
[[noreturn]] void Assert(const AssertionInfo& info);
[[noreturn]] void Abort();
[[noreturn]] void NODE_EXTERN_PRIVATE Assert(const AssertionInfo& info);
[[noreturn]] void NODE_EXTERN_PRIVATE Abort();
void DumpBacktrace(FILE* fp);

// Windows 8+ does not like abort() in Release mode
Expand Down
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