# wasm-utils

[![Build Status](https://travis-ci.org/susytech/wasm-utils.svg?branch=master)](https://travis-ci.org/susytech/wasm-utils)

Collection of WASM utilities used in Susy and WASM contract development

## Build tools for cargo

Easiest way to use is to install via `cargo install`:

```
cargo install susy-pwasm-utils-cli --bin wasm-build
```

## Symbols pruning (wasm-prune)

```
cargo install susy-pwasm-utils-cli --bin wasm-prune
wasm-prune <input_wasm_binary.wasm> <output_wasm_binary.wasm>
```

This will optimize WASM symbols tree to leave only those elements that are used by contract `call` function entry.

## Gas counter (wasm-gas)

For development puposes, raw WASM contract can be injected with gas counters (the same way as it done by Susy runtime when running contracts)

```
cargo install susy-pwasm-utils-cli --bin wasm-gas
wasm-gas <input_wasm_binary.wasm> <output_wasm_binary.wasm>
```

## Externalization (wasm-ext)

Susy WASM runtime provides some library functions that can be commonly found in libc. WASM binary size can be reduced and performance may be improved if these functions are used. This utility scans for invocations of the following functions inside the WASM binary:
- `_malloc`,
- `_free`,
- `_memcpy`,
- `_memset`,
- `_memmove`

And then substitutes them with invocations of the imported ones. Should be run before `wasm-opt` for better results.

```
cargo install susy-pwasm-utils-cli --bin wasm-ext
wasm-ext <input_wasm_binary.wasm> <output_wasm_binary.wasm>
```

## API

All executables use corresponding api methods of the root crate and can be combined in other build tools.

# License

`wasm-utils` is primarily distributed under the terms of both the MIT
license and the Apache License (Version 2.0), at your choice.

See LICENSE-APACHE, and LICENSE-MIT for details.

## Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted
for inclusion in `wasm-utils` by you, as defined in the Apache-2.0 license, shall be
dual licensed as above, without any additional terms or conditions.