Restore Windows support with MSVC (#108)

* switch to MSVC, fixes to support it

* fix linking errors

* document how to patch zcash source

* update hash due to nightly breakage; don't use deprecated bindgen function

* update patch with str4d's upstream suggestion

---------

Co-authored-by: Alfredo Garcia <oxarbitrage@gmail.com>

.github/workflows/ci.yml

@@ -74,7 +74,7 @@ jobs:
     strategy:
       matrix:
         # "windows-latest" was removed; see https://github.com/ZcashFoundation/zcash_script/issues/38
-        os: [ubuntu-latest, macOS-latest]
+        os: [ubuntu-latest, macOS-latest, windows-latest]
     steps:
       - uses: actions/checkout@v4
         with:
@@ -85,16 +85,10 @@ jobs:
       # - name: install LLVM on Mac
       #   if: matrix.os == 'macOS-latest'
       #   run: brew install llvm
-      - name: install LLVM on Windows
-        if: matrix.os == 'windows-latest'
-        run: |
-          choco install llvm -y
-          echo "C:\Program Files\LLVM\bin" | Out-File -FilePath $env:GITHUB_PATH -Encoding utf8 -Append
-          echo "LIBCLANG_PATH=C:\Program Files\LLVM\bin" | Out-File -FilePath $env:GITHUB_ENV -Encoding utf8 -Append
       - uses: actions-rs/toolchain@v1
         if: matrix.os == 'windows-latest'
         with:
-          target: x86_64-pc-windows-gnu
+          target: x86_64-pc-windows-msvc
           toolchain: stable
           profile: minimal
           override: true
@@ -108,7 +102,7 @@ jobs:
         if: matrix.os == 'windows-latest'
         with:
           command: test
-          args: --target x86_64-pc-windows-gnu
+          args: --target x86_64-pc-windows-msvc
       - uses: actions-rs/cargo@v1
         if: matrix.os != 'windows-latest'
         with:

Cargo.lock

@@ -25,13 +25,14 @@ dependencies = [
 
 [[package]]
 name = "ahash"
-version = "0.8.3"
+version = "0.8.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2c99f64d1e06488f620f932677e24bc6e2897582980441ae90a671415bd7ec2f"
+checksum = "8b79b82693f705137f8fb9b37871d99e4f9a7df12b917eed79c3d3954830a60b"
 dependencies = [
  "cfg-if",
  "once_cell",
  "version_check",
+ "zerocopy",
 ]
 
 [[package]]
@@ -96,17 +97,17 @@ dependencies = [
 
 [[package]]
 name = "bindgen"
-version = "0.68.1"
+version = "0.69.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "726e4313eb6ec35d2730258ad4e15b547ee75d6afaa1361a922e78e59b7d8078"
+checksum = "a00dc851838a2120612785d195287475a3ac45514741da670b735818822129a0"
 dependencies = [
  "bitflags 2.4.0",
  "cexpr",
  "clang-sys",
+ "itertools",
  "lazy_static",
  "lazycell",
  "log",
- "peeking_take_while",
  "prettyplease",
  "proc-macro2",
  "quote",
@@ -691,6 +692,15 @@ dependencies = [
  "generic-array",
 ]
 
+[[package]]
+name = "itertools"
+version = "0.12.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ba291022dbbd398a455acf126c1e341954079855bc60dfdda641363bd6922569"
+dependencies = [
+ "either",
+]
+
 [[package]]
 name = "jobserver"
 version = "0.1.26"
@@ -995,12 +1005,6 @@ dependencies = [
  "password-hash",
 ]
 
-[[package]]
-name = "peeking_take_while"
-version = "0.1.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "19b17cddbe7ec3f8bc800887bab5e717348c95ea2ca0b1bf0837fb964dc67099"
-
 [[package]]
 name = "pin-project-lite"
 version = "0.2.13"
@@ -1877,6 +1881,26 @@ dependencies = [
  "zcash_proofs",
 ]
 
+[[package]]
+name = "zerocopy"
+version = "0.7.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "74d4d3961e53fa4c9a25a8637fc2bfaf2595b3d3ae34875568a5cf64787716be"
+dependencies = [
+ "zerocopy-derive",
+]
+
+[[package]]
+name = "zerocopy-derive"
+version = "0.7.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9ce1b18ccd8e73a9321186f97e46f9f04b778851177567b1975109d26a08d2a6"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.35",
+]
+
 [[package]]
 name = "zeroize"
 version = "1.6.0"

README.md

@@ -47,6 +47,11 @@ work correctly. Since we don't allow those in our repository, we start over
 every time, basically using it as a glorified `git clone`. This issue is being
 tracked in https://github.com/ZcashFoundation/zcash_script/issues/35.
 
+We also need to patch the zcash source to enable Windows compatibility. This
+is done by applying a patch file as described below. If the patch application
+fails, check the patch file for reference on what needs to be changed (and
+update the patch file).
+
 If you need to update the zcash source, run:
 
 ```console
@@ -54,6 +59,7 @@ git rm -r depend/zcash
 (commit changes)
 git subtree add -P depend/zcash https://github.com/zcash/zcash.git <ref> --squash
 git rm depend/zcash/Cargo.toml
+git apply zcash.patch
 (commit changes)
 ```
 

build.rs

@@ -32,7 +32,7 @@ fn bindgen_headers() -> Result<()> {
         .header("depend/zcash/src/script/zcash_script.h")
         // Tell cargo to invalidate the built crate whenever any of the
         // included header files changed.
-        .parse_callbacks(Box::new(bindgen::CargoCallbacks))
+        .parse_callbacks(Box::new(bindgen::CargoCallbacks::new()))
         // Finish the builder and generate the bindings.
         .generate()
         .map_err(|_| Error::GenerateBindings)?;
@@ -115,7 +115,7 @@ fn gen_cxxbridge() -> Result<()> {
         fs::create_dir_all(header_path.parent().unwrap()).unwrap();
         fs::write(header_path, output.header).unwrap();
 
-        let src_path = src_out_path.join(format!("{}.c", filename));
+        let src_path = src_out_path.join(format!("{}.cpp", filename));
         // Create output dir if does not exist (since `filename` can have a subdir)
         fs::create_dir_all(src_path.parent().unwrap()).unwrap();
         fs::write(src_path, output.implementation).unwrap();
@@ -203,10 +203,12 @@ fn main() -> Result<()> {
     base_config
         .file("depend/zcash/src/script/zcash_script.cpp")
         .file("depend/zcash/src/util/strencodings.cpp")
+        .file("depend/zcash/src/amount.cpp")
         .file("depend/zcash/src/uint256.cpp")
         .file("depend/zcash/src/pubkey.cpp")
         .file("depend/zcash/src/hash.cpp")
         .file("depend/zcash/src/streams_rust.cpp")
+        .file("depend/zcash/src/zip317.cpp")
         .file("depend/zcash/src/primitives/transaction.cpp")
         .file("depend/zcash/src/crypto/ripemd160.cpp")
         .file("depend/zcash/src/crypto/sha1.cpp")
@@ -217,11 +219,12 @@ fn main() -> Result<()> {
         .file("depend/zcash/src/script/script.cpp")
         .file("depend/zcash/src/script/script_error.cpp")
         .file("depend/zcash/src/support/cleanse.cpp")
+        .file("depend/zcash/src/zcash/cache.cpp")
         // A subset of the files generated by gen_cxxbridge
         // which are required by zcash_script.
-        .file(gen_path.join("src/blake2b.c"))
-        .file(gen_path.join("src/bridge.c"))
-        .file(gen_path.join("src/streams.c"))
+        .file(gen_path.join("src/blake2b.cpp"))
+        .file(gen_path.join("src/bridge.cpp"))
+        .file(gen_path.join("src/streams.cpp"))
         .compile("libzcash_script.a");
 
     Ok(())

depend/zcash/src/zcash/cache.cpp

@@ -3,7 +3,7 @@
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include "zcash/cache.h"
-#include "util/system.h"
+// #include "util/system.h"
 
 namespace libzcash
 {
@@ -11,8 +11,8 @@ std::unique_ptr<BundleValidityCache> NewBundleValidityCache(rust::Str kind, size
 {
     auto cache = std::unique_ptr<BundleValidityCache>(new BundleValidityCache());
     size_t nElems = cache->setup_bytes(nMaxCacheSize);
-    LogPrintf("Using %zu MiB out of %zu requested for %s bundle cache, able to store %zu elements\n",
-              (nElems * sizeof(BundleCacheEntry)) >> 20, nMaxCacheSize >> 20, kind, nElems);
+    // LogPrintf("Using %zu MiB out of %zu requested for %s bundle cache, able to store %zu elements\n",
+    //           (nElems * sizeof(BundleCacheEntry)) >> 20, nMaxCacheSize >> 20, kind, nElems);
     return cache;
 }
 } // namespace libzcash

depend/zcash/src/zcash/cache.h

@@ -31,7 +31,7 @@ public:
     {
         static_assert(hash_select < 8, "BundleCacheHasher only has 8 hashes available.");
         uint32_t u;
-        std::memcpy(&u, key.begin() + 4 * hash_select, 4);
+        std::memcpy(&u, key.data() + 4 * hash_select, 4);
         return u;
     }
 };

zcash.patch

@@ -0,0 +1,37 @@
+diff --git a/depend/zcash/src/zcash/cache.cpp b/depend/zcash/src/zcash/cache.cpp
+index c5cd6b173c..1da334b377 100644
+--- a/depend/zcash/src/zcash/cache.cpp
++++ b/depend/zcash/src/zcash/cache.cpp
+@@ -3,7 +3,7 @@
+ // file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+ #include "zcash/cache.h"
+-#include "util/system.h"
++// #include "util/system.h"
+
+ namespace libzcash
+ {
+@@ -11,8 +11,8 @@ std::unique_ptr<BundleValidityCache> NewBundleValidityCache(rust::Str kind, size
+ {
+     auto cache = std::unique_ptr<BundleValidityCache>(new BundleValidityCache());
+     size_t nElems = cache->setup_bytes(nMaxCacheSize);
+-    LogPrintf("Using %zu MiB out of %zu requested for %s bundle cache, able to store %zu elements\n",
+-              (nElems * sizeof(BundleCacheEntry)) >> 20, nMaxCacheSize >> 20, kind, nElems);
++    // LogPrintf("Using %zu MiB out of %zu requested for %s bundle cache, able to store %zu elements\n",
++    //           (nElems * sizeof(BundleCacheEntry)) >> 20, nMaxCacheSize >> 20, kind, nElems);
+     return cache;
+ }
+ } // namespace libzcash
+diff --git a/depend/zcash/src/zcash/cache.h b/depend/zcash/src/zcash/cache.h
+index 9bef1e43b5..283123bec9 100644
+--- a/depend/zcash/src/zcash/cache.h
++++ b/depend/zcash/src/zcash/cache.h
+@@ -31,7 +31,7 @@ public:
+     {
+         static_assert(hash_select < 8, "BundleCacheHasher only has 8 hashes available.");
+         uint32_t u;
+-        std::memcpy(&u, key.begin() + 4 * hash_select, 4);
++        std::memcpy(&u, key.data() + 4 * hash_select, 4);
+         return u;
+     }
+ };