Initial commit

.gitignore

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+# If you prefer the allow list template instead of the deny list, see community template:
+# https://github.com/github/gitignore/blob/main/community/Golang/Go.AllowList.gitignore
+#
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Test binary, built with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+# Dependency directories (remove the comment below to include it)
+# vendor/
+
+# Go workspace file
+go.work
+go.work.sum
+
+# env file
+.env

LICENSE

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+MIT License
+
+Copyright (c) 2024 Hypermode, Inc.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

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+# WASM Extractor
+
+Reads a `.wasm` file and prints its imports and exports

cli/.gitignore

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+wasmextractor
+wasmextractor.exe

cli/go.mod

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+module wasmextractor
+
+go 1.22.5
+
+require github.com/hypermodeAI/wasmextractor v0.0.0
+
+replace github.com/hypermodeAI/wasmextractor => ../

cli/main.go

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+/*
+ * Copyright 2024 Hypermode, Inc.
+ * MIT License - https://opensource.org/licenses/MIT
+ */
+
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/hypermodeAI/wasmextractor"
+)
+
+func main() {
+
+	if len(os.Args) != 2 {
+		fmt.Fprintf(os.Stderr, "Usage: %s <wasm file>\n", os.Args[0])
+		return
+	}
+
+	wasmFilePath := os.Args[1]
+
+	wasmBytes, err := wasmextractor.ReadWasmFile(wasmFilePath)
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+
+	info, err := wasmextractor.ExtractWasmInfo(wasmBytes)
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+
+	fmt.Println()
+
+	fmt.Println("IMPORTS")
+	fmt.Println("-------")
+	if len(info.Imports) == 0 {
+		fmt.Println("(none)")
+	} else {
+		for _, item := range info.Imports {
+			fmt.Println(&item)
+		}
+	}
+	fmt.Println()
+
+	fmt.Println("EXPORTS")
+	fmt.Println("-------")
+	if len(info.Exports) == 0 {
+		fmt.Println("(none)")
+	} else {
+		for _, item := range info.Exports {
+			fmt.Println(&item)
+		}
+	}
+	fmt.Println()
+}

go.mod

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+module github.com/hypermodeAI/wasmextractor
+
+go 1.22.5

wasmextractor.go

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+/*
+ * Copyright 2024 Hypermode, Inc.
+ * MIT License - https://opensource.org/licenses/MIT
+ */
+
+package wasmextractor
+
+import (
+	"bytes"
+	"encoding/binary"
+	"fmt"
+	"os"
+)
+
+type WasmInfo struct {
+	Imports []WasmItem
+	Exports []WasmItem
+}
+
+type WasmItem struct {
+	Name  string
+	Kind  WasmItemKind
+	Index uint32
+}
+
+func (i *WasmItem) String() string {
+	return fmt.Sprintf("%s: %s (index: %d)", i.Kind, i.Name, i.Index)
+}
+
+type WasmItemKind int32
+
+const (
+	WasmFunction WasmItemKind = 0
+	WasmTable    WasmItemKind = 1
+	WasmMemory   WasmItemKind = 2
+	WasmGlobal   WasmItemKind = 3
+)
+
+func (k WasmItemKind) String() string {
+	switch k {
+	case WasmFunction:
+		return "Function"
+	case WasmTable:
+		return "Table"
+	case WasmMemory:
+		return "Memory"
+	case WasmGlobal:
+		return "Global"
+	default:
+		return "Unknown"
+	}
+}
+
+func ReadWasmFile(wasmFilePath string) ([]byte, error) {
+	wasmBytes, err := os.ReadFile(wasmFilePath)
+	if err != nil {
+		return nil, fmt.Errorf("error reading wasm file: %v", err)
+	}
+
+	magic := []byte{0x00, 0x61, 0x73, 0x6D} // "\0asm"
+	if len(wasmBytes) < 8 || !bytes.Equal(wasmBytes[:4], magic) {
+		return nil, fmt.Errorf("invalid wasm file")
+	}
+
+	if binary.LittleEndian.Uint32(wasmBytes[4:8]) != 1 {
+		return nil, fmt.Errorf("unsupported wasm version")
+	}
+
+	return wasmBytes, nil
+}
+
+func ExtractWasmInfo(wasmBytes []byte) (*WasmInfo, error) {
+	info := &WasmInfo{}
+
+	offset := 8
+	for offset < len(wasmBytes) {
+		sectionID := wasmBytes[offset]
+		offset++
+
+		size, n := binary.Uvarint(wasmBytes[offset:])
+		offset += n
+
+		switch sectionID {
+		case 2: // Import section
+			info.Imports = readImports(wasmBytes[offset : offset+int(size)])
+
+		case 7: // Export section
+			info.Exports = readExports(wasmBytes[offset : offset+int(size)])
+		}
+
+		offset += int(size)
+	}
+
+	return info, nil
+}
+
+func readImports(data []byte) []WasmItem {
+
+	numItems, n := binary.Uvarint(data)
+	offset := n
+
+	imports := make([]WasmItem, numItems)
+
+	for i := 0; i < int(numItems); i++ {
+		moduleLen, n := binary.Uvarint(data[offset:])
+		offset += n
+
+		moduleName := string(data[offset : offset+int(moduleLen)])
+		offset += int(moduleLen)
+
+		fieldLen, n := binary.Uvarint(data[offset:])
+		offset += n
+
+		fieldName := string(data[offset : offset+int(fieldLen)])
+		offset += int(fieldLen)
+
+		kind := data[offset]
+		offset++
+
+		index, n := binary.Uvarint(data[offset:])
+		offset += n
+
+		imports[i] = WasmItem{
+			Name:  fmt.Sprintf("%s.%s", moduleName, fieldName),
+			Kind:  WasmItemKind(kind),
+			Index: uint32(index),
+		}
+	}
+
+	return imports
+}
+
+func readExports(data []byte) []WasmItem {
+
+	numItems, n := binary.Uvarint(data)
+	offset := n
+
+	exports := make([]WasmItem, numItems)
+
+	for i := 0; i < int(numItems); i++ {
+		fieldLen, n := binary.Uvarint(data[offset:])
+		offset += n
+
+		fieldName := string(data[offset : offset+int(fieldLen)])
+		offset += int(fieldLen)
+
+		kind := data[offset]
+		offset++
+
+		index, n := binary.Uvarint(data[offset:])
+		offset += n
+
+		exports[i] = WasmItem{
+			Name:  fieldName,
+			Kind:  WasmItemKind(kind),
+			Index: uint32(index),
+		}
+	}
+
+	return exports
+}