move libsais wrappers out of vendor folder so they don't get wiped out

Author: YoavCodes

.gitignore

@@ -13,10 +13,6 @@ bin/*
 
 # Vendored dependencies
 vendors/
-!vendors/libsais/
-vendors/libsais/*
-!vendors/libsais/zig_wrapper.c
-!vendors/libsais/zig_wrapper.h
 
 # OS files
 .DS_Store

build.zig

@@ -67,6 +67,7 @@ pub fn build(b: *std.Build) void {
     // This is for the cImport to import the .h files
     bsdiff.addIncludePath(b.path("zstd/lib"));
     bsdiff.addIncludePath(b.path("vendors/libsais"));
+    bsdiff.addIncludePath(b.path("src/libsais-wrapper"));
 
     b.installArtifact(bsdiff);
 
@@ -90,6 +91,7 @@ pub fn build(b: *std.Build) void {
 
     tests.addIncludePath(b.path("zstd/lib"));
     tests.addIncludePath(b.path("vendors/libsais"));
+    tests.addIncludePath(b.path("src/libsais-wrapper"));
     tests.linkLibrary(libzstd);
     tests.addObjectFile(b.path("vendors/libsais/libsais.a"));
 

scripts/setup.js

@@ -8,7 +8,7 @@
  */
 
 import { execSync } from 'child_process';
-import { existsSync, mkdirSync, rmSync, unlinkSync, renameSync } from 'fs';
+import { existsSync, mkdirSync, rmSync, unlinkSync, renameSync, writeFileSync } from 'fs';
 import { join } from 'path';
 
 const ZIG_VERSION = '0.13.0';
@@ -57,10 +57,24 @@ async function vendorLibsais() {
     // Compile libsais (Zig's C backend has issues with libsais)
     console.log('Compiling libsais...');
 
-    // Use clang/gcc on all platforms for consistency
-    // This produces .a libraries that work with Zig's linker
+    const compiler = platform === 'win32' ? 'gcc' : 'clang';
+    const wrapperDir = join(process.cwd(), 'src', 'libsais-wrapper');
+
+    // Compile libsais source files
+    execSync(
+      `cd ${libsaisDir} && ${compiler} -c -O3 -std=c99 libsais.c libsais64.c`,
+      { stdio: 'inherit' }
+    );
+
+    // Compile wrapper with include path to libsais headers
+    execSync(
+      `${compiler} -c -O3 -std=c99 -I ${libsaisDir} ${wrapperDir}/zig_wrapper.c -o ${libsaisDir}/zig_wrapper.o`,
+      { stdio: 'inherit' }
+    );
+
+    // Create static library
     execSync(
-      `cd ${libsaisDir} && ${platform === 'win32' ? 'gcc' : 'clang'} -c -O3 -std=c99 libsais.c libsais64.c zig_wrapper.c && ar rcs libsais.a libsais.o libsais64.o zig_wrapper.o`,
+      `cd ${libsaisDir} && ar rcs libsais.a libsais.o libsais64.o zig_wrapper.o`,
       { stdio: 'inherit' }
     );
 

src/libsais-wrapper/zig_wrapper.c

@@ -0,0 +1,15 @@
+// Simple C wrapper for libsais64 to ensure clean ABI for Zig
+#include "libsais64.h"
+#include <stddef.h>
+#include <stdint.h>
+
+// Wrapper function with explicit types and no macros
+int64_t zig_libsais64_wrapper(
+    const uint8_t * T,
+    int64_t * SA,
+    int64_t n
+) {
+    // Call libsais64 with default parameters
+    // fs=0 means no extra space, freq=NULL means no frequency table
+    return libsais64(T, SA, n, 0, NULL);
+}

src/libsais-wrapper/zig_wrapper.h

@@ -0,0 +1,14 @@
+// Simple C wrapper for libsais64 to ensure clean ABI for Zig
+#ifndef ZIG_WRAPPER_H
+#define ZIG_WRAPPER_H
+
+#include <stdint.h>
+
+// Simple wrapper with no macros or complex types
+int64_t zig_libsais64_wrapper(
+    const uint8_t * T,
+    int64_t * SA,
+    int64_t n
+);
+
+#endif