Match max program size of regexp package (#89)

wasilibs · Apr 19, 2024 · ea78258 · ea78258
1 parent c11c53d
commit ea78258
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Showing 4 changed files with 46 additions and 30 deletions.
diff --git a/internal/cre2/cre2.go b/internal/cre2/cre2.go
@@ -25,6 +25,7 @@ void cre2_opt_set_longest_match(void* opt, int flag);
 void cre2_opt_set_posix_syntax(void* opt, int flag);
 void cre2_opt_set_case_sensitive(void* opt, int flag);
 void cre2_opt_set_latin1_encoding(void* opt);
+void cre2_opt_set_max_mem(void* opt, int64_t size);
 
 void* malloc(size_t size);
 void free(void* ptr);
@@ -107,6 +108,10 @@ func OptSetLatin1Encoding(opt unsafe.Pointer) {
 	C.cre2_opt_set_latin1_encoding(opt)
 }
 
+func OptSetMaxMem(opt unsafe.Pointer, size int) {
+	C.cre2_opt_set_max_mem(opt, C.int64_t(size))
+}
+
 func Malloc(size int) unsafe.Pointer {
 	return C.malloc(C.size_t(size))
 }

diff --git a/internal/re2.go b/internal/re2.go
@@ -11,6 +11,10 @@ import (
 	"unicode/utf8"
 )
 
+// Use same max size as regexp package.
+// https://github.com/golang/go/blob/master/src/regexp/syntax/parse.go#L95
+const maxSize = 128 << 20
+
 type Regexp struct {
 	ptr wasmPtr
 

diff --git a/internal/re2_tinygowasm.go b/internal/re2_tinygowasm.go
@@ -30,6 +30,7 @@ func (abi *libre2ABI) endOperation(allocation) {
 func newRE(abi *libre2ABI, pattern cString, opts CompileOptions) wasmPtr {
 	opt := cre2.NewOpt()
 	defer cre2.DeleteOpt(opt)
+	cre2.OptSetMaxMem(opt, maxSize)
 	cre2.OptSetLogErrors(opt, false)
 	if opts.Longest {
 		cre2.OptSetLongestMatch(opt, true)

diff --git a/internal/re2_wazero.go b/internal/re2_wazero.go
@@ -63,6 +63,7 @@ type libre2ABI struct {
 	cre2OptSetPosixSyntax     lazyFunction
 	cre2OptSetCaseSensitive   lazyFunction
 	cre2OptSetLatin1Encoding  lazyFunction
+	cre2OptSetMaxMem          lazyFunction
 
 	malloc lazyFunction
 	free   lazyFunction
@@ -219,6 +220,7 @@ func newABI() *libre2ABI {
 		cre2OptSetPosixSyntax:     newLazyFunction("cre2_opt_set_posix_syntax"),
 		cre2OptSetCaseSensitive:   newLazyFunction("cre2_opt_set_case_sensitive"),
 		cre2OptSetLatin1Encoding:  newLazyFunction("cre2_opt_set_latin1_encoding"),
+		cre2OptSetMaxMem:          newLazyFunction("cre2_opt_set_max_mem"),
 
 		malloc: newLazyFunction("malloc"),
 		free:   newLazyFunction("free"),
@@ -238,44 +240,48 @@ func (abi *libre2ABI) endOperation(a allocation) {
 func newRE(abi *libre2ABI, pattern cString, opts CompileOptions) wasmPtr {
 	ctx := context.Background()
 	optPtr := uint32(0)
-	if opts != (CompileOptions{}) {
-		res, err := abi.cre2OptNew.Call0(ctx)
-		if err != nil {
+	res, err := abi.cre2OptNew.Call0(ctx)
+	if err != nil {
+		panic(err)
+	}
+	optPtr = uint32(res)
+	defer func() {
+		if _, err := abi.cre2OptDelete.Call1(ctx, uint64(optPtr)); err != nil {
 			panic(err)
 		}
-		optPtr = uint32(res)
-		defer func() {
-			if _, err := abi.cre2OptDelete.Call1(ctx, uint64(optPtr)); err != nil {
-				panic(err)
-			}
-		}()
-		if opts.Longest {
-			_, err = abi.cre2OptSetLongestMatch.Call2(ctx, uint64(optPtr), 1)
-			if err != nil {
-				panic(err)
-			}
+	}()
+
+	_, err = abi.cre2OptSetMaxMem.Call2(ctx, uint64(optPtr), uint64(maxSize))
+	if err != nil {
+		panic(err)
+	}
+
+	if opts.Longest {
+		_, err = abi.cre2OptSetLongestMatch.Call2(ctx, uint64(optPtr), 1)
+		if err != nil {
+			panic(err)
 		}
-		if opts.Posix {
-			_, err = abi.cre2OptSetPosixSyntax.Call2(ctx, uint64(optPtr), 1)
-			if err != nil {
-				panic(err)
-			}
+	}
+	if opts.Posix {
+		_, err = abi.cre2OptSetPosixSyntax.Call2(ctx, uint64(optPtr), 1)
+		if err != nil {
+			panic(err)
 		}
-		if opts.CaseInsensitive {
-			_, err = abi.cre2OptSetCaseSensitive.Call2(ctx, uint64(optPtr), 0)
-			if err != nil {
-				panic(err)
-			}
+	}
+	if opts.CaseInsensitive {
+		_, err = abi.cre2OptSetCaseSensitive.Call2(ctx, uint64(optPtr), 0)
+		if err != nil {
+			panic(err)
 		}
-		if opts.Latin1 {
-			_, err = abi.cre2OptSetLatin1Encoding.Call1(ctx, uint64(optPtr))
-			if err != nil {
-				panic(err)
-			}
+	}
+	if opts.Latin1 {
+		_, err = abi.cre2OptSetLatin1Encoding.Call1(ctx, uint64(optPtr))
+		if err != nil {
+			panic(err)
 		}
 	}
 
-	res, err := abi.cre2New.Call3(ctx, uint64(pattern.ptr), uint64(pattern.length), uint64(optPtr))
+	res, err = abi.cre2New.Call3(ctx, uint64(pattern.ptr), uint64(pattern.length), uint64(optPtr))
 	if err != nil {
 		panic(err)
 	}