LibCrypto: Add libtommath vcpkg dependency and link it

An overlay port is required to add the `stdc-iec-559` and `install-pc`
patches.

The `stdc-iec-559` patch is required because Clang doesn't define
`__STDC_IEC_559__`. However, glibc and musl define it if `__GCC_IEC_559`
is not defined. The macro is taken from glibc source code.

The `install-pc` patch is required because libtommath doesn't install
the pkg-config files when building statically compromising our ability
to find it during build.

Clang: https://clang.llvm.org/c_status.html#:~:text=Yes-,
IEC%2060559%20support,-Unknown
glibc: https://sourceware.org/git/?p=glibc.git;a=blob;
f=include/stdc-predef.h

Libraries/LibCrypto/CMakeLists.txt

@@ -34,5 +34,9 @@ set(SOURCES
 serenity_lib(LibCrypto crypto)
 target_link_libraries(LibCrypto PRIVATE LibCore)
 
+find_package(PkgConfig REQUIRED)
+pkg_check_modules(libtommath REQUIRED IMPORTED_TARGET libtommath)
+target_link_libraries(LibCrypto PRIVATE PkgConfig::libtommath)
+
 find_package(OpenSSL REQUIRED)
 target_link_libraries(LibCrypto PUBLIC OpenSSL::Crypto)

Meta/CMake/vcpkg/overlay-ports/libtommath/bcrypt.patch

@@ -0,0 +1,67 @@
+diff --git a/CMakeLists.txt b/CMakeLists.txt
+--- a/CMakeLists.txt
++++ b/CMakeLists.txt
+@@ -22,8 +22,10 @@
+ #-----------------------------------------------------------------------------
+ include(GNUInstallDirs)
+ include(CheckIPOSupported)
+ include(CMakePackageConfigHelpers)
++include(CMakePushCheckState)
++include(CheckSymbolExists)
+ # default is "No tests"
+ option(BUILD_TESTING "" OFF)
+ include(CTest)
+ include(sources.cmake)
+@@ -118,8 +120,19 @@
+ target_link_options(${PROJECT_NAME} BEFORE PRIVATE
+     ${LTM_LD_FLAGS}
+ )
+ 
++if(MSVC)
++    cmake_push_check_state()
++    set(CMAKE_REQUIRED_LIBRARIES bcrypt)
++    check_symbol_exists(BCryptGenRandom "Windows.h;bcrypt.h" BCRYPT_AVAILABLE)
++    cmake_pop_check_state()
++    if(BCRYPT_AVAILABLE)
++        target_compile_definitions(${PROJECT_NAME} PRIVATE LTM_WIN32_BCRYPT)
++        target_link_libraries(${PROJECT_NAME} PRIVATE bcrypt)
++    endif()
++endif()
++
+ set(PUBLIC_HEADERS tommath.h)
+ set(C89 False CACHE BOOL "(Usually maintained automatically) Enable when the library is in c89 mode to package the correct header files on install")
+ if(C89)
+     list(APPEND PUBLIC_HEADERS tommath_c89.h)
+diff --git a/bn_s_mp_rand_platform.c b/bn_s_mp_rand_platform.c
+--- a/bn_s_mp_rand_platform.c
++++ b/bn_s_mp_rand_platform.c
+@@ -28,8 +28,19 @@
+ #endif
+ 
+ #define WIN32_LEAN_AND_MEAN
+ #include <windows.h>
++
++#ifdef LTM_WIN32_BCRYPT
++#include <bcrypt.h>
++#pragma comment(lib, "bcrypt")
++
++static mp_err s_read_wincsp(void *p, size_t n)
++{
++   return BCRYPT_SUCCESS(BCryptGenRandom(NULL, (PUCHAR)p, (ULONG)n,
++                                         BCRYPT_USE_SYSTEM_PREFERRED_RNG)) ? MP_OKAY : MP_ERR;
++}
++#else
+ #include <wincrypt.h>
+ 
+ static mp_err s_read_wincsp(void *p, size_t n)
+ {
+@@ -45,8 +56,9 @@
+       hProv = h;
+    }
+    return CryptGenRandom(hProv, (DWORD)n, (BYTE *)p) == TRUE ? MP_OKAY : MP_ERR;
+ }
++#endif
+ #endif /* WIN32 */
+ 
+ #if !defined(BN_S_READ_WINCSP_C) && defined(__linux__) && defined(__GLIBC_PREREQ)
+ #if __GLIBC_PREREQ(2, 25)

Meta/CMake/vcpkg/overlay-ports/libtommath/has-set-double.patch

@@ -0,0 +1,14 @@
+diff --git a/bn_mp_set_double.c b/bn_mp_set_double.c
+--- a/bn_mp_set_double.c
++++ b/bn_mp_set_double.c
+@@ -2,9 +2,9 @@
+ #ifdef BN_MP_SET_DOUBLE_C
+ /* LibTomMath, multiple-precision integer library -- Tom St Denis */
+ /* SPDX-License-Identifier: Unlicense */
+ 
+-#if defined(__STDC_IEC_559__) || defined(__GCC_IEC_559)
++#if defined(__STDC_IEC_559__) || defined(__GCC_IEC_559) || defined(_MSC_VER)
+ mp_err mp_set_double(mp_int *a, double b)
+ {
+    uint64_t frac;
+    int exp;

Meta/CMake/vcpkg/overlay-ports/libtommath/import-lib.patch

@@ -0,0 +1,12 @@
+diff --git a/sources.cmake b/sources.cmake
+--- a/sources.cmake
++++ b/sources.cmake
+@@ -171,4 +171,8 @@
+ tommath_cutoffs.h
+ tommath_private.h
+ tommath_superclass.h
+ )
++
++if(WIN32)
++    list(APPEND SOURCES tommath.def)
++endif()

Meta/CMake/vcpkg/overlay-ports/libtommath/install-pc.patch

@@ -0,0 +1,12 @@
+diff --git a/CMakeLists.txt b/CMakeLists.txt
+--- a/CMakeLists.txt
++++ b/CMakeLists.txt
+@@ -168,7 +168,7 @@ install(TARGETS ${PROJECT_NAME}
+ )
+
+ # Install libtommath.pc for pkg-config if we build a shared library
+-if(BUILD_SHARED_LIBS)
++if(BUILD_SHARED_LIBS OR TRUE)
+     # Let the user override the default directory of the pkg-config file (usually this shouldn't be required to be changed)
+     set(CMAKE_INSTALL_PKGCONFIGDIR "${CMAKE_INSTALL_LIBDIR}/pkgconfig" CACHE PATH "Folder where to install .pc files")
+

Meta/CMake/vcpkg/overlay-ports/libtommath/msvc-dce.patch

@@ -0,0 +1,21 @@
+diff --git a/bn_s_mp_rand_platform.c b/bn_s_mp_rand_platform.c
+--- a/bn_s_mp_rand_platform.c
++++ b/bn_s_mp_rand_platform.c
+@@ -136,13 +136,17 @@
+ 
+ mp_err s_mp_rand_platform(void *p, size_t n)
+ {
+    mp_err err = MP_ERR;
++   #ifndef _MSC_VER
+    if ((err != MP_OKAY) && MP_HAS(S_READ_ARC4RANDOM)) err = s_read_arc4random(p, n);
++   #endif
+    if ((err != MP_OKAY) && MP_HAS(S_READ_WINCSP))     err = s_read_wincsp(p, n);
++   #ifndef _MSC_VER
+    if ((err != MP_OKAY) && MP_HAS(S_READ_GETRANDOM))  err = s_read_getrandom(p, n);
+    if ((err != MP_OKAY) && MP_HAS(S_READ_URANDOM))    err = s_read_urandom(p, n);
+    if ((err != MP_OKAY) && MP_HAS(S_READ_LTM_RNG))    err = s_read_ltm_rng(p, n);
++   #endif
+    return err;
+ }
+ 
+ #endif

Meta/CMake/vcpkg/overlay-ports/libtommath/portfile.cmake

@@ -0,0 +1,27 @@
+vcpkg_from_github(
+    OUT_SOURCE_PATH SOURCE_PATH
+    REPO libtom/libtommath
+    REF "v${VERSION}"
+    SHA512 3dbd7053a670afa563a069a9785f1aa4cab14a210bcd05d8fc7db25bd3dcce36b10a3f4f54ca92d75a694f891226f01bdf6ac15bacafeb93a8be6b04c579beb3
+    HEAD_REF develop
+    PATCHES
+        bcrypt.patch
+        import-lib.patch
+        has-set-double.patch # Remove in next release.
+        msvc-dce.patch # This is a won't fix, see https://github.com/libtom/libtommath/blob/develop/s_mp_rand_platform.c#L120-L138
+        stdc-iec-559.patch # Define __STDC_IEC_559__ like glibc and musl do.
+        install-pc.patch # Always install pkgconfig file, even when building statically.
+)
+
+vcpkg_cmake_configure(
+    SOURCE_PATH "${SOURCE_PATH}"
+)
+vcpkg_cmake_install()
+vcpkg_copy_pdbs()
+vcpkg_cmake_config_fixup(CONFIG_PATH "lib/cmake/${PORT}")
+vcpkg_fixup_pkgconfig()
+vcpkg_install_copyright(FILE_LIST "${SOURCE_PATH}/LICENSE")
+
+file(INSTALL "${CMAKE_CURRENT_LIST_DIR}/usage" DESTINATION "${CURRENT_PACKAGES_DIR}/share/${PORT}")
+file(REMOVE_RECURSE "${CURRENT_PACKAGES_DIR}/debug/include")
+file(REMOVE_RECURSE "${CURRENT_PACKAGES_DIR}/debug/share")

Meta/CMake/vcpkg/overlay-ports/libtommath/stdc-iec-559.patch

@@ -0,0 +1,20 @@
+diff --git a/bn_mp_set_double.c b/bn_mp_set_double.c
+--- a/bn_mp_set_double.c
++++ b/bn_mp_set_double.c
+@@ -3,6 +3,16 @@
+ /* LibTomMath, multiple-precision integer library -- Tom St Denis */
+ /* SPDX-License-Identifier: Unlicense */
+ 
++#ifdef __GCC_IEC_559
++# if __GCC_IEC_559 > 0
++#  define __STDC_IEC_559__              1
++#  define __STDC_IEC_60559_BFP__        201404L
++# endif
++#else
++# define __STDC_IEC_559__               1
++# define __STDC_IEC_60559_BFP__         201404L
++#endif
++
+ #if defined(__STDC_IEC_559__) || defined(__GCC_IEC_559) || defined(_MSC_VER)
+ mp_err mp_set_double(mp_int *a, double b)
+ {

Meta/CMake/vcpkg/overlay-ports/libtommath/usage

@@ -0,0 +1,9 @@
+libtommath provides CMake targets:
+
+  find_package(libtommath CONFIG REQUIRED)
+  target_link_libraries(main PRIVATE libtommath)
+
+libtommath provides pkg-config modules:
+
+  # public domain library for manipulating large integer numbers
+  libtommath

Meta/CMake/vcpkg/overlay-ports/libtommath/vcpkg.json

@@ -0,0 +1,17 @@
+{
+  "name": "libtommath",
+  "version": "1.3.0",
+  "port-version": 2,
+  "description": "LibTomMath is a free open source portable number theoretic multiple-precision integer library written entirely in C.",
+  "homepage": "https://www.libtom.net/LibTomMath/",
+  "dependencies": [
+    {
+      "name": "vcpkg-cmake",
+      "host": true
+    },
+    {
+      "name": "vcpkg-cmake-config",
+      "host": true
+    }
+  ]
+}

vcpkg.json

@@ -70,6 +70,7 @@
         "dav1d"
       ]
     },
+    "libtommath",
     {
       "name": "libwebp",
       "features": [
@@ -172,6 +173,10 @@
       "name": "libproxy",
       "version": "0.4.18#3"
     },
+    {
+      "name": "libtommath",
+      "version": "1.3.0#2"
+    },
     {
       "name": "libavif",
       "version": "1.0.4#1"