Johnathan Blow's pastebin - a windows library finder
// | |
// Author: Jonathan Blow | |
// Version: 1 | |
// Date: 31 August, 2018 | |
// | |
// This code is released under the MIT license, which you can find at | |
// | |
// https://opensource.org/licenses/MIT | |
// | |
// | |
// | |
// See the comments for how to use this library just below the includes. | |
// | |
#include <windows.h> | |
#include <stdlib.h> | |
#include <string.h> | |
#include <assert.h> | |
#include <stdio.h> | |
#include <sys/stat.h> | |
#include <stdint.h> | |
#include <io.h> // For _get_osfhandle | |
// | |
// HOW TO USE THIS CODE | |
// | |
// The purpose of this file is to find the folders that contain libraries | |
// you may need to link against, on Windows, if you are linking with any | |
// compiled C or C++ code. This will be necessary for many non-C++ programming | |
// language environments that want to provide compatibility. | |
// | |
// We find the place where the Visual Studio libraries live (for example, | |
// libvcruntime.lib), where the linker and compiler executables live | |
// (for example, link.exe), and where the Windows SDK libraries reside | |
// (kernel32.lib, libucrt.lib). | |
// | |
// We all wish you didn't have to worry about so many weird dependencies, | |
// but we don't really have a choice about this, sadly. | |
// | |
// I don't claim that this is the absolute best way to solve this problem, | |
// and so far we punt on things (if you have multiple versions of Visual Studio | |
// installed, we return the first one, rather than the newest). But it | |
// will solve the basic problem for you as simply as I know how to do it, | |
// and because there isn't too much code here, it's easy to modify and expand. | |
// | |
// | |
// Here is the API you need to know about: | |
// | |
struct Find_Result { | |
int windows_sdk_version; // Zero if no Windows SDK found. | |
wchar_t *windows_sdk_root = NULL; | |
wchar_t *windows_sdk_um_library_path = NULL; | |
wchar_t *windows_sdk_ucrt_library_path = NULL; | |
wchar_t *vs_exe_path = NULL; | |
wchar_t *vs_library_path = NULL; | |
}; | |
Find_Result find_visual_studio_and_windows_sdk(); | |
void free_resources(Find_Result *result) { | |
free(result->windows_sdk_root); | |
free(result->windows_sdk_um_library_path); | |
free(result->windows_sdk_ucrt_library_path); | |
free(result->vs_exe_path); | |
free(result->vs_library_path); | |
} | |
// | |
// Call find_visual_studio_and_windows_sdk, look at the resulting | |
// paths, then call free_resources on the result. | |
// | |
// Everything else in this file is implementation details that you | |
// don't need to care about. | |
// | |
// | |
// This file was about 400 lines before we started adding these comments. | |
// You might think that's way too much code to do something as simple | |
// as finding a few library and executable paths. I agree. However, | |
// Microsoft's own solution to this problem, called "vswhere", is a | |
// mere EIGHT THOUSAND LINE PROGRAM, spread across 70 files, | |
// that they posted to github *unironically*. | |
// | |
// I am not making this up: https://github.com/Microsoft/vswhere | |
// | |
// Several people have therefore found the need to solve this problem | |
// themselves. We referred to some of these other solutions when | |
// figuring out what to do, most prominently ziglang's version, | |
// by Ryan Saunderson. | |
// | |
// I hate this kind of code. The fact that we have to do this at all | |
// is stupid, and the actual maneuvers we need to go through | |
// are just painful. If programming were like this all the time, | |
// I would quit. | |
// | |
// Because this is such an absurd waste of time, I felt it would be | |
// useful to package the code in an easily-reusable way, in the | |
// style of the stb libraries. We haven't gone as all-out as some | |
// of the stb libraries do (which compile in C with no includes, often). | |
// For this version you need C++ and the headers at the top of the file. | |
// | |
// We return the strings as Windows wide character strings. Aesthetically | |
// I don't like that (I think most sane programs are UTF-8 internally), | |
// but apparently, not all valid Windows file paths can even be converted | |
// correctly to UTF-8. So have fun with that. It felt safest and simplest | |
// to stay with wchar_t since all of this code is fully ensconced in | |
// Windows crazy-land. | |
// | |
// One other shortcut I took is that this is hardcoded to return the | |
// folders for x64 libraries. If you want x86 or arm, you can make | |
// slight edits to the code below, or, if enough people want this, | |
// I can work it in here. | |
// | |
// Defer macro/thing. | |
#define CONCAT_INTERNAL(x,y) x##y | |
#define CONCAT(x,y) CONCAT_INTERNAL(x,y) | |
template<typename T> | |
struct ExitScope { | |
T lambda; | |
ExitScope(T lambda):lambda(lambda){} | |
~ExitScope(){lambda();} | |
ExitScope(const ExitScope&); | |
private: | |
ExitScope& operator =(const ExitScope&); | |
}; | |
class ExitScopeHelp { | |
public: | |
template<typename T> | |
ExitScope<T> operator+(T t){ return t;} | |
}; | |
#define defer const auto& CONCAT(defer__, __LINE__) = ExitScopeHelp() + [&]() | |
// COM objects for the ridiculous Microsoft craziness. | |
struct DECLSPEC_UUID("B41463C3-8866-43B5-BC33-2B0676F7F42E") DECLSPEC_NOVTABLE ISetupInstance : public IUnknown | |
{ | |
STDMETHOD(GetInstanceId)(_Out_ BSTR* pbstrInstanceId) = 0; | |
STDMETHOD(GetInstallDate)(_Out_ LPFILETIME pInstallDate) = 0; | |
STDMETHOD(GetInstallationName)(_Out_ BSTR* pbstrInstallationName) = 0; | |
STDMETHOD(GetInstallationPath)(_Out_ BSTR* pbstrInstallationPath) = 0; | |
STDMETHOD(GetInstallationVersion)(_Out_ BSTR* pbstrInstallationVersion) = 0; | |
STDMETHOD(GetDisplayName)(_In_ LCID lcid, _Out_ BSTR* pbstrDisplayName) = 0; | |
STDMETHOD(GetDescription)(_In_ LCID lcid, _Out_ BSTR* pbstrDescription) = 0; | |
STDMETHOD(ResolvePath)(_In_opt_z_ LPCOLESTR pwszRelativePath, _Out_ BSTR* pbstrAbsolutePath) = 0; | |
}; | |
struct DECLSPEC_UUID("6380BCFF-41D3-4B2E-8B2E-BF8A6810C848") DECLSPEC_NOVTABLE IEnumSetupInstances : public IUnknown | |
{ | |
STDMETHOD(Next)(_In_ ULONG celt, _Out_writes_to_(celt, *pceltFetched) ISetupInstance** rgelt, _Out_opt_ _Deref_out_range_(0, celt) ULONG* pceltFetched) = 0; | |
STDMETHOD(Skip)(_In_ ULONG celt) = 0; | |
STDMETHOD(Reset)(void) = 0; | |
STDMETHOD(Clone)(_Deref_out_opt_ IEnumSetupInstances** ppenum) = 0; | |
}; | |
struct DECLSPEC_UUID("42843719-DB4C-46C2-8E7C-64F1816EFD5B") DECLSPEC_NOVTABLE ISetupConfiguration : public IUnknown | |
{ | |
STDMETHOD(EnumInstances)(_Out_ IEnumSetupInstances** ppEnumInstances) = 0; | |
STDMETHOD(GetInstanceForCurrentProcess)(_Out_ ISetupInstance** ppInstance) = 0; | |
STDMETHOD(GetInstanceForPath)(_In_z_ LPCWSTR wzPath, _Out_ ISetupInstance** ppInstance) = 0; | |
}; | |
// The beginning of the actual code that does things. | |
struct Version_Data { | |
int32_t best_version[4]; // For Windows 8 versions, only two of these numbers are used. | |
wchar_t *best_name; | |
}; | |
bool os_file_exists(wchar_t *name) { | |
// @Robustness: What flags do we really want to check here? | |
auto attrib = GetFileAttributesW(name); | |
if (attrib == INVALID_FILE_ATTRIBUTES) return false; | |
if (attrib & FILE_ATTRIBUTE_DIRECTORY) return false; | |
return true; | |
} | |
wchar_t *concat(wchar_t *a, wchar_t *b, wchar_t *c = nullptr, wchar_t *d = nullptr) { | |
// Concatenate up to 4 wide strings together. Allocated with malloc. | |
// If you don't like that, use a programming language that actually | |
// helps you with using custom allocators. Or just edit the code. | |
auto len_a = wcslen(a); | |
auto len_b = wcslen(b); | |
auto len_c = 0; | |
if (c) len_c = wcslen(c); | |
auto len_d = 0; | |
if (d) len_d = wcslen(d); | |
wchar_t *result = (wchar_t *)malloc((len_a + len_b + len_c + len_d + 1) * 2); | |
memcpy(result, a, len_a*2); | |
memcpy(result + len_a, b, len_b*2); | |
if (c) memcpy(result + len_a + len_b, c, len_c * 2); | |
if (d) memcpy(result + len_a + len_b + len_c, d, len_d * 2); | |
result[len_a + len_b + len_c + len_d] = 0; | |
return result; | |
} | |
typedef void (*Visit_Proc_W)(wchar_t *short_name, wchar_t *full_name, Version_Data *data); | |
bool visit_files_w(wchar_t *dir_name, Version_Data *data, Visit_Proc_W proc) { | |
// Visit everything in one folder (non-recursively). If it's a directory | |
// that doesn't start with ".", call the visit proc on it. The visit proc | |
// will see if the filename conforms to the expected versioning pattern. | |
auto wildcard_name = concat(dir_name, L"\\*"); | |
defer { free(wildcard_name); }; | |
WIN32_FIND_DATAW find_data; | |
auto handle = FindFirstFileW(wildcard_name, &find_data); | |
if (handle == INVALID_HANDLE_VALUE) return false; | |
while (true) { | |
if ((find_data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) && (find_data.cFileName[0] != '.')) { | |
auto full_name = concat(dir_name, L"\\", find_data.cFileName); | |
defer { free(full_name); }; | |
proc(find_data.cFileName, full_name, data); | |
} | |
auto success = FindNextFileW(handle, &find_data); | |
if (!success) break; | |
} | |
FindClose(handle); | |
return true; | |
} | |
wchar_t *find_windows_kit_root(HKEY key, wchar_t *version) { | |
// Given a key to an already opened registry entry, | |
// get the value stored under the 'version' subkey. | |
// If that's not the right terminology, hey, I never do registry stuff. | |
DWORD required_length; | |
auto rc = RegQueryValueExW(key, version, NULL, NULL, NULL, &required_length); | |
if (rc != 0) return NULL; | |
DWORD length = required_length + 2; // The +2 is for the maybe optional zero later on. Probably we are over-allocating. | |
wchar_t *value = (wchar_t *)malloc(length); | |
if (!value) return NULL; | |
rc = RegQueryValueExW(key, version, NULL, NULL, (LPBYTE)value, &length); // We know that version is zero-terminated... | |
if (rc != 0) return NULL; | |
// The documentation says that if the string for some reason was not stored | |
// with zero-termination, we need to manually terminate it. Sigh!! | |
if (value[length]) { | |
value[length+1] = 0; | |
} | |
return value; | |
} | |
void win10_best(wchar_t *short_name, wchar_t *full_name, Version_Data *data) { | |
// Find the Windows 10 subdirectory with the highest version number. | |
int i0, i1, i2, i3; | |
auto success = swscanf_s(short_name, L"%d.%d.%d.%d", &i0, &i1, &i2, &i3); | |
if (success < 4) return; | |
if (i0 < data->best_version[0]) return; | |
else if (i0 == data->best_version[0]) { | |
if (i1 < data->best_version[1]) return; | |
else if (i1 == data->best_version[1]) { | |
if (i2 < data->best_version[2]) return; | |
else if (i2 == data->best_version[2]) { | |
if (i3 < data->best_version[3]) return; | |
} | |
} | |
} | |
// we have to copy_string and free here because visit_files free's the full_name string | |
// after we execute this function, so Win*_Data would contain an invalid pointer. | |
if (data->best_name) free(data->best_name); | |
data->best_name = _wcsdup(full_name); | |
if (data->best_name) { | |
data->best_version[0] = i0; | |
data->best_version[1] = i1; | |
data->best_version[2] = i2; | |
data->best_version[3] = i3; | |
} | |
} | |
void win8_best(wchar_t *short_name, wchar_t *full_name, Version_Data *data) { | |
// Find the Windows 8 subdirectory with the highest version number. | |
int i0, i1; | |
auto success = swscanf_s(short_name, L"winv%d.%d", &i0, &i1); | |
if (success < 2) return; | |
if (i0 < data->best_version[0]) return; | |
else if (i0 == data->best_version[0]) { | |
if (i1 < data->best_version[1]) return; | |
} | |
// we have to copy_string and free here because visit_files free's the full_name string | |
// after we execute this function, so Win*_Data would contain an invalid pointer. | |
if (data->best_name) free(data->best_name); | |
data->best_name = _wcsdup(full_name); | |
if (data->best_name) { | |
data->best_version[0] = i0; | |
data->best_version[1] = i1; | |
} | |
} | |
void find_windows_kit_root(Find_Result *result) { | |
// Information about the Windows 10 and Windows 8 development kits | |
// is stored in the same place in the registry. We open a key | |
// to that place, first checking preferntially for a Windows 10 kit, | |
// then, if that's not found, a Windows 8 kit. | |
HKEY main_key; | |
auto rc = RegOpenKeyExA(HKEY_LOCAL_MACHINE, "SOFTWARE\\Microsoft\\Windows Kits\\Installed Roots", | |
0, KEY_QUERY_VALUE | KEY_WOW64_32KEY | KEY_ENUMERATE_SUB_KEYS, &main_key); | |
if (rc != S_OK) return; | |
defer { RegCloseKey(main_key); }; | |
// Look for a Windows 10 entry. | |
auto windows10_root = find_windows_kit_root(main_key, L"KitsRoot10"); | |
if (windows10_root) { | |
defer { free(windows10_root); }; | |
Version_Data data = {0}; | |
auto windows10_lib = concat(windows10_root, L"Lib"); | |
defer { free(windows10_lib); }; | |
visit_files_w(windows10_lib, &data, win10_best); | |
if (data.best_name) { | |
result->windows_sdk_version = 10; | |
result->windows_sdk_root = data.best_name; | |
return; | |
} | |
} | |
// Look for a Windows 8 entry. | |
auto windows8_root = find_windows_kit_root(main_key, L"KitsRoot81"); | |
if (windows8_root) { | |
defer { free(windows8_root); }; | |
auto windows8_lib = concat(windows8_root, L"Lib"); | |
defer { free(windows8_lib); }; | |
Version_Data data = {0}; | |
visit_files_w(windows8_lib, &data, win8_best); | |
if (data.best_name) { | |
result->windows_sdk_version = 8; | |
result->windows_sdk_root = data.best_name; | |
return; | |
} | |
} | |
// If we get here, we failed to find anything. | |
} | |
void find_visual_studio_by_fighting_through_microsoft_craziness(Find_Result *result) { | |
// The name of this procedure is kind of cryptic. Its purpose is | |
// to fight through Microsoft craziness. The things that the fine | |
// Visual Studio team want you to do, JUST TO FIND A SINGLE FOLDER | |
// THAT EVERYONE NEEDS TO FIND, are ridiculous garbage. | |
// For earlier versions of Visual Studio, you'd find this information in the registry, | |
// similarly to the Windows Kits above. But no, now it's the future, so to ask the | |
// question "Where is the Visual Studio folder?" you have to do a bunch of COM object | |
// instantiation, enumeration, and querying. (For extra bonus points, try doing this in | |
// a new, underdeveloped programming language where you don't have COM routines up | |
// and running yet. So fun.) | |
// | |
// If all this COM object instantiation, enumeration, and querying doesn't give us | |
// a useful result, we drop back to the registry-checking method. | |
auto rc = CoInitialize(NULL); | |
// "Subsequent valid calls return false." So ignore false. | |
// if rc != S_OK return false; | |
GUID my_uid = {0x42843719, 0xDB4C, 0x46C2, {0x8E, 0x7C, 0x64, 0xF1, 0x81, 0x6E, 0xFD, 0x5B}}; | |
GUID CLSID_SetupConfiguration = {0x177F0C4A, 0x1CD3, 0x4DE7, {0xA3, 0x2C, 0x71, 0xDB, 0xBB, 0x9F, 0xA3, 0x6D}}; | |
ISetupConfiguration *config = NULL; | |
auto hr = CoCreateInstance(CLSID_SetupConfiguration, NULL, CLSCTX_INPROC_SERVER, my_uid, (void **)&config); | |
if (hr != 0) return; | |
defer { config->Release(); }; | |
IEnumSetupInstances *instances = NULL; | |
hr = config->EnumInstances(&instances); | |
if (hr != 0) return; | |
if (!instances) return; | |
defer { instances->Release(); }; | |
while (1) { | |
ULONG found = 0; | |
ISetupInstance *instance = NULL; | |
auto hr = instances->Next(1, &instance, &found); | |
if (hr != S_OK) break; | |
defer { instance->Release(); }; | |
BSTR bstr_inst_path; | |
hr = instance->GetInstallationPath(&bstr_inst_path); | |
if (hr != S_OK) continue; | |
defer { SysFreeString(bstr_inst_path); }; | |
auto tools_filename = concat(bstr_inst_path, L"\\VC\\Auxiliary\\Build\\Microsoft.VCToolsVersion.default.txt"); | |
defer { free(tools_filename); }; | |
FILE *f = nullptr; | |
auto open_result = _wfopen_s(&f, tools_filename, L"rt"); | |
if (open_result != 0) continue; | |
if (!f) continue; | |
defer { fclose(f); }; | |
LARGE_INTEGER tools_file_size; | |
auto file_handle = (HANDLE)_get_osfhandle(_fileno(f)); | |
BOOL success = GetFileSizeEx(file_handle, &tools_file_size); | |
if (!success) continue; | |
auto version_bytes = (tools_file_size.QuadPart + 1) * 2; // Warning: This multiplication by 2 presumes there is no variable-length encoding in the wchars (wacky characters in the file could betray this expectation). | |
wchar_t *version = (wchar_t *)malloc(version_bytes); | |
defer { free(version); }; | |
auto read_result = fgetws(version, version_bytes, f); | |
if (!read_result) continue; | |
auto version_tail = wcschr(version, '\n'); | |
if (version_tail) *version_tail = 0; // Stomp the data, because nobody cares about it. | |
auto library_path = concat(bstr_inst_path, L"\\VC\\Tools\\MSVC\\", version, L"\\lib\\x64"); | |
auto library_file = concat(library_path, L"\\vcruntime.lib"); // @Speed: Could have library_path point to this string, with a smaller count, to save on memory flailing! | |
if (os_file_exists(library_file)) { | |
auto link_exe_path = concat(bstr_inst_path, L"\\VC\\Tools\\MSVC\\", version, L"\\bin\\Hostx64\\x64"); | |
result->vs_exe_path = link_exe_path; | |
result->vs_library_path = library_path; | |
return; | |
} | |
/* | |
Ryan Saunderson said: | |
"Clang uses the 'SetupInstance->GetInstallationVersion' / ISetupHelper->ParseVersion to find the newest version | |
and then reads the tools file to define the tools path - which is definitely better than what i did." | |
So... @Incomplete: Should probably pick the newest version... | |
*/ | |
} | |
// If we get here, we didn't find Visual Studio 2017. Try earlier versions. | |
HKEY vs7_key; | |
rc = RegOpenKeyExA(HKEY_LOCAL_MACHINE, "SOFTWARE\\Microsoft\\VisualStudio\\SxS\\VS7", 0, KEY_QUERY_VALUE | KEY_WOW64_32KEY, &vs7_key); | |
if (rc != S_OK) return; | |
defer { RegCloseKey(vs7_key); }; | |
// Hardcoded search for 4 prior Visual Studio versions. Is there something better to do here? | |
wchar_t *versions[] = { L"14.0", L"12.0", L"11.0", L"10.0" }; | |
const int NUM_VERSIONS = sizeof(versions) / sizeof(versions[0]); | |
for (int i = 0; i < NUM_VERSIONS; i++) { | |
auto v = versions[i]; | |
DWORD dw_type; | |
DWORD cb_data; | |
auto rc = RegQueryValueExW(vs7_key, v, NULL, &dw_type, NULL, &cb_data); | |
if ((rc == ERROR_FILE_NOT_FOUND) || (dw_type != REG_SZ)) { | |
continue; | |
} | |
auto buffer = (wchar_t *)malloc(cb_data); | |
if (!buffer) return; | |
defer { free(buffer); }; | |
rc = RegQueryValueExW(vs7_key, v, NULL, NULL, (LPBYTE)buffer, &cb_data); | |
if (rc != 0) continue; | |
// @Robustness: Do the zero-termination thing suggested in the RegQueryValue docs? | |
auto lib_path = concat(buffer, L"VC\\Lib\\amd64"); | |
// Check to see whether a vcruntime.lib actually exists here. | |
auto vcruntime_filename = concat(lib_path, L"\\vcruntime.lib"); | |
defer { free(vcruntime_filename); }; | |
if (os_file_exists(vcruntime_filename)) { | |
result->vs_exe_path = concat(buffer, L"VC\\bin"); | |
result->vs_library_path = lib_path; | |
return; | |
} | |
free(lib_path); | |
} | |
// If we get here, we failed to find anything. | |
} | |
Find_Result find_visual_studio_and_windows_sdk() { | |
Find_Result result; | |
find_windows_kit_root(&result); | |
if (result.windows_sdk_root) { | |
result.windows_sdk_um_library_path = concat(result.windows_sdk_root, L"\\um\\x64"); | |
result.windows_sdk_ucrt_library_path = concat(result.windows_sdk_root, L"\\ucrt\\x64"); | |
} | |
find_visual_studio_by_fighting_through_microsoft_craziness(&result); | |
return result; | |
} |
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