Tiny binary writer utility, just enough for you
cargo install hexoUse hexo -h to get complete CLI manual.
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log-level: Set log level, possible values:debug,info,warn,error,none. Default:info. -
safe: Enable safe mode, will disable unsafe functions likecmdandeval. Default:false
Takes source file in hexo format and compiles it to binary file output
hexo build --source <path to source> --output <path to output>Takes source file in hexo format and compiles it to binary file output. Will recompile on source file change
hexo watch --source <path to source> --output <path to output>To emit a byte use glyph > fallowed by byte value:
> 0a // by default numbers are interpreted as hexadecimal, will emit decimal 10
> 'HelloWorld' // will emit utf-8 bytes of 'HelloWorld' string
> 10x22 // you can specifiy arbitrary radix in range 2..36, will emit decimal 22
To declare a constant use glyph $ fallowed by constant name and value:
$ class_name 'HelloWorld'
Then you can use it as if you used hex or binary string by prefixing it with $:
> $class_name
You can declare arbitrary functions using glyph # fallowed by function name and body:
# class_declaration {
> 0100
> #len($0)
> $0
}
Function arguments are referenced by their index: $0, $1, $2, ...
To call a function use glyph # fallowed by function name and arguments:
// String functions
> #len('HelloWorld') // will emit length of 'HelloWorld' in bytes (0a)
// OS functions
> #cmd(`ls`) // will emit result of command line 'ls' command
> #read_file('file.txt') // will emit content of 'file.txt'
// Padding functions
> #pad_left(AA, 4) // will emit '00 00 00 AA'
> #pad_right(AA, 4) // will emit 'AA 00 00 00'
> #pad('AA', left: 10x4, right: 10x8) // wil pad left by 4 bytes and right by 8 bytes
// Hexo compiler
> #eval('> 01 02 03') // will evaluate passed argument and return resulting compilation
Let's write 'HelloWorld' Java class bytecode:
$ class_name 'HelloWorld'
$ object_superclass_name 'java/lang/Object'
# class_declaration {
> 0100
> #len($0)
> $0
}
> cafe babe // Magic number
> 0000 0034 // Java Bytecode version
> 0005 // Constant pool size
> 0700 02 // Class at index 2
> #class_declaration($class_name)
> 0700 04 // Class at index 4
> #class_declaration($object_superclass_name)
> 0021 // Supper public
> 0001 0003 // Class pointers
> 0000 0000 0000 0000 // No interfaces, fields, methods, attributes
No, Hexo only supports big endian currently. But we are currently investigating ability to support both big and small endian.
Not currently, but this is planned for future releases.
Yes, safety is no goal of Hexo, please don't run untrusted code with it.
You can use safe mode to disable cmd and eval functions.
Please add --safe flag before command to enable it.
As Hexo is designed for quick and dirty tasks, we decided to make it as flexible as possible. Thus safe by default approach will only complicate workflow without adding any meaningful value.