Fixing output of eth_call and Bytes deserialization (#2230)

* Fixing eth_call to builtins

* Fixing bytes deserialization

* Removing comment
This commit is contained in:
Tomasz Drwięga 2016-09-22 14:50:00 +02:00 committed by Gav Wood
parent 07b5e9a5c7
commit 15488b3e40
5 changed files with 147 additions and 68 deletions

View File

@ -17,14 +17,15 @@
use crypto::sha2::Sha256 as Sha256Digest; use crypto::sha2::Sha256 as Sha256Digest;
use crypto::ripemd160::Ripemd160 as Ripemd160Digest; use crypto::ripemd160::Ripemd160 as Ripemd160Digest;
use crypto::digest::Digest; use crypto::digest::Digest;
use util::*; use std::cmp::min;
use util::{U256, H256, Hashable, FixedHash, BytesRef};
use ethkey::{Signature, recover as ec_recover}; use ethkey::{Signature, recover as ec_recover};
use ethjson; use ethjson;
/// Native implementation of a built-in contract. /// Native implementation of a built-in contract.
pub trait Impl: Send + Sync { pub trait Impl: Send + Sync {
/// execute this built-in on the given input, writing to the given output. /// execute this built-in on the given input, writing to the given output.
fn execute(&self, input: &[u8], out: &mut [u8]); fn execute(&self, input: &[u8], output: &mut BytesRef);
} }
/// A gas pricing scheme for built-in contracts. /// A gas pricing scheme for built-in contracts.
@ -56,7 +57,7 @@ impl Builtin {
pub fn cost(&self, s: usize) -> U256 { self.pricer.cost(s) } pub fn cost(&self, s: usize) -> U256 { self.pricer.cost(s) }
/// Simple forwarder for execute. /// Simple forwarder for execute.
pub fn execute(&self, input: &[u8], output: &mut[u8]) { self.native.execute(input, output) } pub fn execute(&self, input: &[u8], output: &mut BytesRef) { self.native.execute(input, output) }
} }
impl From<ethjson::spec::Builtin> for Builtin { impl From<ethjson::spec::Builtin> for Builtin {
@ -108,14 +109,13 @@ struct Sha256;
struct Ripemd160; struct Ripemd160;
impl Impl for Identity { impl Impl for Identity {
fn execute(&self, input: &[u8], output: &mut [u8]) { fn execute(&self, input: &[u8], output: &mut BytesRef) {
let len = min(input.len(), output.len()); output.write(0, input);
output[..len].copy_from_slice(&input[..len]);
} }
} }
impl Impl for EcRecover { impl Impl for EcRecover {
fn execute(&self, i: &[u8], output: &mut [u8]) { fn execute(&self, i: &[u8], output: &mut BytesRef) {
let len = min(i.len(), 128); let len = min(i.len(), 128);
let mut input = [0; 128]; let mut input = [0; 128];
@ -135,58 +135,34 @@ impl Impl for EcRecover {
if s.is_valid() { if s.is_valid() {
if let Ok(p) = ec_recover(&s, &hash) { if let Ok(p) = ec_recover(&s, &hash) {
let r = p.sha3(); let r = p.sha3();
output.write(0, &[0; 12]);
let out_len = min(output.len(), 32); output.write(12, &r[12..r.len()]);
for x in &mut output[0.. min(12, out_len)] {
*x = 0;
}
if out_len > 12 {
output[12..out_len].copy_from_slice(&r[12..out_len]);
}
} }
} }
} }
} }
impl Impl for Sha256 { impl Impl for Sha256 {
fn execute(&self, input: &[u8], output: &mut [u8]) { fn execute(&self, input: &[u8], output: &mut BytesRef) {
let out_len = min(output.len(), 32);
let mut sha = Sha256Digest::new(); let mut sha = Sha256Digest::new();
sha.input(input); sha.input(input);
if out_len == 32 { let mut out = [0; 32];
sha.result(&mut output[0..32]); sha.result(&mut out);
} else {
let mut out = [0; 32];
sha.result(&mut out);
output.copy_from_slice(&out[..out_len]) output.write(0, &out);
}
} }
} }
impl Impl for Ripemd160 { impl Impl for Ripemd160 {
fn execute(&self, input: &[u8], output: &mut [u8]) { fn execute(&self, input: &[u8], output: &mut BytesRef) {
let out_len = min(output.len(), 32);
let mut sha = Ripemd160Digest::new(); let mut sha = Ripemd160Digest::new();
sha.input(input); sha.input(input);
for x in &mut output[0.. min(12, out_len)] { let mut out = [0; 32];
*x = 0; sha.result(&mut out[12..32]);
}
if out_len >= 32 { output.write(0, &out);
sha.result(&mut output[12..32]);
} else if out_len > 12 {
let mut out = [0; 20];
sha.result(&mut out);
output.copy_from_slice(&out[12..out_len])
}
} }
} }
@ -194,7 +170,7 @@ impl Impl for Ripemd160 {
mod tests { mod tests {
use super::{Builtin, Linear, ethereum_builtin, Pricer}; use super::{Builtin, Linear, ethereum_builtin, Pricer};
use ethjson; use ethjson;
use util::U256; use util::{U256, BytesRef};
#[test] #[test]
fn identity() { fn identity() {
@ -203,15 +179,15 @@ mod tests {
let i = [0u8, 1, 2, 3]; let i = [0u8, 1, 2, 3];
let mut o2 = [255u8; 2]; let mut o2 = [255u8; 2];
f.execute(&i[..], &mut o2[..]); f.execute(&i[..], &mut BytesRef::Fixed(&mut o2[..]));
assert_eq!(i[0..2], o2); assert_eq!(i[0..2], o2);
let mut o4 = [255u8; 4]; let mut o4 = [255u8; 4];
f.execute(&i[..], &mut o4[..]); f.execute(&i[..], &mut BytesRef::Fixed(&mut o4[..]));
assert_eq!(i, o4); assert_eq!(i, o4);
let mut o8 = [255u8; 8]; let mut o8 = [255u8; 8];
f.execute(&i[..], &mut o8[..]); f.execute(&i[..], &mut BytesRef::Fixed(&mut o8[..]));
assert_eq!(i, o8[..4]); assert_eq!(i, o8[..4]);
assert_eq!([255u8; 4], o8[4..]); assert_eq!([255u8; 4], o8[4..]);
} }
@ -224,16 +200,20 @@ mod tests {
let i = [0u8; 0]; let i = [0u8; 0];
let mut o = [255u8; 32]; let mut o = [255u8; 32];
f.execute(&i[..], &mut o[..]); f.execute(&i[..], &mut BytesRef::Fixed(&mut o[..]));
assert_eq!(&o[..], &(FromHex::from_hex("e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855").unwrap())[..]); assert_eq!(&o[..], &(FromHex::from_hex("e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855").unwrap())[..]);
let mut o8 = [255u8; 8]; let mut o8 = [255u8; 8];
f.execute(&i[..], &mut o8[..]); f.execute(&i[..], &mut BytesRef::Fixed(&mut o8[..]));
assert_eq!(&o8[..], &(FromHex::from_hex("e3b0c44298fc1c14").unwrap())[..]); assert_eq!(&o8[..], &(FromHex::from_hex("e3b0c44298fc1c14").unwrap())[..]);
let mut o34 = [255u8; 34]; let mut o34 = [255u8; 34];
f.execute(&i[..], &mut o34[..]); f.execute(&i[..], &mut BytesRef::Fixed(&mut o34[..]));
assert_eq!(&o34[..], &(FromHex::from_hex("e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855ffff").unwrap())[..]); assert_eq!(&o34[..], &(FromHex::from_hex("e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855ffff").unwrap())[..]);
let mut ov = vec![];
f.execute(&i[..], &mut BytesRef::Flexible(&mut ov));
assert_eq!(&ov[..], &(FromHex::from_hex("e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855").unwrap())[..]);
} }
#[test] #[test]
@ -244,15 +224,15 @@ mod tests {
let i = [0u8; 0]; let i = [0u8; 0];
let mut o = [255u8; 32]; let mut o = [255u8; 32];
f.execute(&i[..], &mut o[..]); f.execute(&i[..], &mut BytesRef::Fixed(&mut o[..]));
assert_eq!(&o[..], &(FromHex::from_hex("0000000000000000000000009c1185a5c5e9fc54612808977ee8f548b2258d31").unwrap())[..]); assert_eq!(&o[..], &(FromHex::from_hex("0000000000000000000000009c1185a5c5e9fc54612808977ee8f548b2258d31").unwrap())[..]);
let mut o8 = [255u8; 8]; let mut o8 = [255u8; 8];
f.execute(&i[..], &mut o8[..]); f.execute(&i[..], &mut BytesRef::Fixed(&mut o8[..]));
assert_eq!(&o8[..], &(FromHex::from_hex("0000000000000000").unwrap())[..]); assert_eq!(&o8[..], &(FromHex::from_hex("0000000000000000").unwrap())[..]);
let mut o34 = [255u8; 34]; let mut o34 = [255u8; 34];
f.execute(&i[..], &mut o34[..]); f.execute(&i[..], &mut BytesRef::Fixed(&mut o34[..]));
assert_eq!(&o34[..], &(FromHex::from_hex("0000000000000000000000009c1185a5c5e9fc54612808977ee8f548b2258d31ffff").unwrap())[..]); assert_eq!(&o34[..], &(FromHex::from_hex("0000000000000000000000009c1185a5c5e9fc54612808977ee8f548b2258d31ffff").unwrap())[..]);
} }
@ -272,46 +252,46 @@ mod tests {
let i = FromHex::from_hex("47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad000000000000000000000000000000000000000000000000000000000000001b650acf9d3f5f0a2c799776a1254355d5f4061762a237396a99a0e0e3fc2bcd6729514a0dacb2e623ac4abd157cb18163ff942280db4d5caad66ddf941ba12e03").unwrap(); let i = FromHex::from_hex("47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad000000000000000000000000000000000000000000000000000000000000001b650acf9d3f5f0a2c799776a1254355d5f4061762a237396a99a0e0e3fc2bcd6729514a0dacb2e623ac4abd157cb18163ff942280db4d5caad66ddf941ba12e03").unwrap();
let mut o = [255u8; 32]; let mut o = [255u8; 32];
f.execute(&i[..], &mut o[..]); f.execute(&i[..], &mut BytesRef::Fixed(&mut o[..]));
assert_eq!(&o[..], &(FromHex::from_hex("000000000000000000000000c08b5542d177ac6686946920409741463a15dddb").unwrap())[..]); assert_eq!(&o[..], &(FromHex::from_hex("000000000000000000000000c08b5542d177ac6686946920409741463a15dddb").unwrap())[..]);
let mut o8 = [255u8; 8]; let mut o8 = [255u8; 8];
f.execute(&i[..], &mut o8[..]); f.execute(&i[..], &mut BytesRef::Fixed(&mut o8[..]));
assert_eq!(&o8[..], &(FromHex::from_hex("0000000000000000").unwrap())[..]); assert_eq!(&o8[..], &(FromHex::from_hex("0000000000000000").unwrap())[..]);
let mut o34 = [255u8; 34]; let mut o34 = [255u8; 34];
f.execute(&i[..], &mut o34[..]); f.execute(&i[..], &mut BytesRef::Fixed(&mut o34[..]));
assert_eq!(&o34[..], &(FromHex::from_hex("000000000000000000000000c08b5542d177ac6686946920409741463a15dddbffff").unwrap())[..]); assert_eq!(&o34[..], &(FromHex::from_hex("000000000000000000000000c08b5542d177ac6686946920409741463a15dddbffff").unwrap())[..]);
let i_bad = FromHex::from_hex("47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad000000000000000000000000000000000000000000000000000000000000001a650acf9d3f5f0a2c799776a1254355d5f4061762a237396a99a0e0e3fc2bcd6729514a0dacb2e623ac4abd157cb18163ff942280db4d5caad66ddf941ba12e03").unwrap(); let i_bad = FromHex::from_hex("47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad000000000000000000000000000000000000000000000000000000000000001a650acf9d3f5f0a2c799776a1254355d5f4061762a237396a99a0e0e3fc2bcd6729514a0dacb2e623ac4abd157cb18163ff942280db4d5caad66ddf941ba12e03").unwrap();
let mut o = [255u8; 32]; let mut o = [255u8; 32];
f.execute(&i_bad[..], &mut o[..]); f.execute(&i_bad[..], &mut BytesRef::Fixed(&mut o[..]));
assert_eq!(&o[..], &(FromHex::from_hex("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap())[..]); assert_eq!(&o[..], &(FromHex::from_hex("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap())[..]);
let i_bad = FromHex::from_hex("47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad000000000000000000000000000000000000000000000000000000000000001b000000000000000000000000000000000000000000000000000000000000001b0000000000000000000000000000000000000000000000000000000000000000").unwrap(); let i_bad = FromHex::from_hex("47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad000000000000000000000000000000000000000000000000000000000000001b000000000000000000000000000000000000000000000000000000000000001b0000000000000000000000000000000000000000000000000000000000000000").unwrap();
let mut o = [255u8; 32]; let mut o = [255u8; 32];
f.execute(&i_bad[..], &mut o[..]); f.execute(&i_bad[..], &mut BytesRef::Fixed(&mut o[..]));
assert_eq!(&o[..], &(FromHex::from_hex("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap())[..]); assert_eq!(&o[..], &(FromHex::from_hex("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap())[..]);
let i_bad = FromHex::from_hex("47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad000000000000000000000000000000000000000000000000000000000000001b0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001b").unwrap(); let i_bad = FromHex::from_hex("47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad000000000000000000000000000000000000000000000000000000000000001b0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001b").unwrap();
let mut o = [255u8; 32]; let mut o = [255u8; 32];
f.execute(&i_bad[..], &mut o[..]); f.execute(&i_bad[..], &mut BytesRef::Fixed(&mut o[..]));
assert_eq!(&o[..], &(FromHex::from_hex("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap())[..]); assert_eq!(&o[..], &(FromHex::from_hex("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap())[..]);
let i_bad = FromHex::from_hex("47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad000000000000000000000000000000000000000000000000000000000000001bffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff000000000000000000000000000000000000000000000000000000000000001b").unwrap(); let i_bad = FromHex::from_hex("47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad000000000000000000000000000000000000000000000000000000000000001bffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff000000000000000000000000000000000000000000000000000000000000001b").unwrap();
let mut o = [255u8; 32]; let mut o = [255u8; 32];
f.execute(&i_bad[..], &mut o[..]); f.execute(&i_bad[..], &mut BytesRef::Fixed(&mut o[..]));
assert_eq!(&o[..], &(FromHex::from_hex("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap())[..]); assert_eq!(&o[..], &(FromHex::from_hex("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap())[..]);
let i_bad = FromHex::from_hex("47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad000000000000000000000000000000000000000000000000000000000000001b000000000000000000000000000000000000000000000000000000000000001bffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap(); let i_bad = FromHex::from_hex("47173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad000000000000000000000000000000000000000000000000000000000000001b000000000000000000000000000000000000000000000000000000000000001bffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap();
let mut o = [255u8; 32]; let mut o = [255u8; 32];
f.execute(&i_bad[..], &mut o[..]); f.execute(&i_bad[..], &mut BytesRef::Fixed(&mut o[..]));
assert_eq!(&o[..], &(FromHex::from_hex("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap())[..]); assert_eq!(&o[..], &(FromHex::from_hex("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap())[..]);
// TODO: Should this (corrupted version of the above) fail rather than returning some address? // TODO: Should this (corrupted version of the above) fail rather than returning some address?
/* let i_bad = FromHex::from_hex("48173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad000000000000000000000000000000000000000000000000000000000000001b650acf9d3f5f0a2c799776a1254355d5f4061762a237396a99a0e0e3fc2bcd6729514a0dacb2e623ac4abd157cb18163ff942280db4d5caad66ddf941ba12e03").unwrap(); /* let i_bad = FromHex::from_hex("48173285a8d7341e5e972fc677286384f802f8ef42a5ec5f03bbfa254cb01fad000000000000000000000000000000000000000000000000000000000000001b650acf9d3f5f0a2c799776a1254355d5f4061762a237396a99a0e0e3fc2bcd6729514a0dacb2e623ac4abd157cb18163ff942280db4d5caad66ddf941ba12e03").unwrap();
let mut o = [255u8; 32]; let mut o = [255u8; 32];
f.execute(&i_bad[..], &mut o[..]); f.execute(&i_bad[..], &mut BytesRef::Fixed(&mut o[..]));
assert_eq!(&o[..], &(FromHex::from_hex("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap())[..]);*/ assert_eq!(&o[..], &(FromHex::from_hex("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap())[..]);*/
} }
@ -336,7 +316,7 @@ mod tests {
let i = [0u8, 1, 2, 3]; let i = [0u8, 1, 2, 3];
let mut o = [255u8; 4]; let mut o = [255u8; 4];
b.execute(&i[..], &mut o[..]); b.execute(&i[..], &mut BytesRef::Fixed(&mut o[..]));
assert_eq!(i, o); assert_eq!(i, o);
} }
@ -357,7 +337,7 @@ mod tests {
let i = [0u8, 1, 2, 3]; let i = [0u8, 1, 2, 3];
let mut o = [255u8; 4]; let mut o = [255u8; 4];
b.execute(&i[..], &mut o[..]); b.execute(&i[..], &mut BytesRef::Fixed(&mut o[..]));
assert_eq!(i, o); assert_eq!(i, o);
} }
} }

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@ -45,7 +45,7 @@ pub trait Engine : Sync + Send {
fn extra_info(&self, _header: &Header) -> HashMap<String, String> { HashMap::new() } fn extra_info(&self, _header: &Header) -> HashMap<String, String> { HashMap::new() }
/// Additional information. /// Additional information.
fn additional_params(&self) -> HashMap<String, String> { HashMap::new() } fn additional_params(&self) -> HashMap<String, String> { HashMap::new() }
/// Get the general parameters of the chain. /// Get the general parameters of the chain.
fn params(&self) -> &CommonParams; fn params(&self) -> &CommonParams;
@ -126,7 +126,7 @@ pub trait Engine : Sync + Send {
fn cost_of_builtin(&self, a: &Address, input: &[u8]) -> U256 { self.builtins().get(a).unwrap().cost(input.len()) } fn cost_of_builtin(&self, a: &Address, input: &[u8]) -> U256 { self.builtins().get(a).unwrap().cost(input.len()) }
/// Execution the builtin contract `a` on `input` and return `output`. /// Execution the builtin contract `a` on `input` and return `output`.
/// Panics if `is_builtin(a)` is not true. /// Panics if `is_builtin(a)` is not true.
fn execute_builtin(&self, a: &Address, input: &[u8], output: &mut [u8]) { self.builtins().get(a).unwrap().execute(input, output); } fn execute_builtin(&self, a: &Address, input: &[u8], output: &mut BytesRef) { self.builtins().get(a).unwrap().execute(input, output); }
// TODO: sealing stuff - though might want to leave this for later. // TODO: sealing stuff - though might want to leave this for later.
} }

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@ -193,7 +193,6 @@ impl<'a> Executive<'a> {
data: Some(t.data.clone()), data: Some(t.data.clone()),
call_type: CallType::Call, call_type: CallType::Call,
}; };
// TODO: move output upstream
let mut out = vec![]; let mut out = vec![];
(self.call(params, &mut substate, BytesRef::Flexible(&mut out), &mut tracer, &mut vm_tracer), out) (self.call(params, &mut substate, BytesRef::Flexible(&mut out), &mut tracer, &mut vm_tracer), out)
} }

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@ -70,7 +70,7 @@ impl Visitor for BytesVisitor {
type Value = Bytes; type Value = Bytes;
fn visit_str<E>(&mut self, value: &str) -> Result<Self::Value, E> where E: Error { fn visit_str<E>(&mut self, value: &str) -> Result<Self::Value, E> where E: Error {
if value.len() >= 2 && &value[0..2] == "0x" { if value.len() >= 2 && &value[0..2] == "0x" && value.len() & 1 == 0 {
Ok(Bytes::new(FromHex::from_hex(&value[2..]).unwrap_or_else(|_| vec![]))) Ok(Bytes::new(FromHex::from_hex(&value[2..]).unwrap_or_else(|_| vec![])))
} else { } else {
Err(Error::custom("invalid hex")) Err(Error::custom("invalid hex"))
@ -95,5 +95,21 @@ mod tests {
let serialized = serde_json::to_string(&bytes).unwrap(); let serialized = serde_json::to_string(&bytes).unwrap();
assert_eq!(serialized, r#""0x0123456789abcdef""#); assert_eq!(serialized, r#""0x0123456789abcdef""#);
} }
#[test]
fn test_bytes_deserialize() {
let bytes1: Result<Bytes, serde_json::Error> = serde_json::from_str(r#""""#);
let bytes2: Result<Bytes, serde_json::Error> = serde_json::from_str(r#""0x123""#);
let bytes3: Bytes = serde_json::from_str(r#""0x""#).unwrap();
let bytes4: Bytes = serde_json::from_str(r#""0x12""#).unwrap();
let bytes5: Bytes = serde_json::from_str(r#""0x0123""#).unwrap();
assert!(bytes1.is_err());
assert!(bytes2.is_err());
assert_eq!(bytes3, Bytes(vec![]));
assert_eq!(bytes4, Bytes(vec![0x12]));
assert_eq!(bytes5, Bytes(vec![0x1, 0x23]));
}
} }

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@ -20,6 +20,7 @@
//! as //! as
use std::fmt; use std::fmt;
use std::cmp::min;
use std::ops::{Deref, DerefMut}; use std::ops::{Deref, DerefMut};
/// Slice pretty print helper /// Slice pretty print helper
@ -71,6 +72,32 @@ pub enum BytesRef<'a> {
Fixed(&'a mut [u8]) Fixed(&'a mut [u8])
} }
impl<'a> BytesRef<'a> {
/// Writes given `input` to this `BytesRef` starting at `offset`.
/// Returns number of bytes written to the ref.
/// NOTE can return number greater then `input.len()` in case flexible vector had to be extended.
pub fn write(&mut self, offset: usize, input: &[u8]) -> usize {
match *self {
BytesRef::Flexible(ref mut data) => {
let data_len = data.len();
let wrote = input.len() + if data_len > offset { 0 } else { offset - data_len };
data.resize(offset, 0);
data.extend_from_slice(input);
wrote
},
BytesRef::Fixed(ref mut data) if offset < data.len() => {
let max = min(data.len() - offset, input.len());
for i in 0..max {
data[offset + i] = input[i];
}
max
},
_ => 0
}
}
}
impl<'a> Deref for BytesRef<'a> { impl<'a> Deref for BytesRef<'a> {
type Target = [u8]; type Target = [u8];
@ -92,4 +119,61 @@ impl <'a> DerefMut for BytesRef<'a> {
} }
/// Vector of bytes. /// Vector of bytes.
pub type Bytes = Vec<u8>; pub type Bytes = Vec<u8>;
#[cfg(test)]
mod tests {
use super::BytesRef;
#[test]
fn should_write_bytes_to_fixed_bytesref() {
// given
let mut data1 = vec![0, 0, 0];
let mut data2 = vec![0, 0, 0];
let (res1, res2) = {
let mut bytes1 = BytesRef::Fixed(&mut data1[..]);
let mut bytes2 = BytesRef::Fixed(&mut data2[1..2]);
// when
let res1 = bytes1.write(1, &[1, 1, 1]);
let res2 = bytes2.write(3, &[1, 1, 1]);
(res1, res2)
};
// then
assert_eq!(&data1, &[0, 1, 1]);
assert_eq!(res1, 2);
assert_eq!(&data2, &[0, 0, 0]);
assert_eq!(res2, 0);
}
#[test]
fn should_write_bytes_to_flexible_bytesref() {
// given
let mut data1 = vec![0, 0, 0];
let mut data2 = vec![0, 0, 0];
let mut data3 = vec![0, 0, 0];
let (res1, res2, res3) = {
let mut bytes1 = BytesRef::Flexible(&mut data1);
let mut bytes2 = BytesRef::Flexible(&mut data2);
let mut bytes3 = BytesRef::Flexible(&mut data3);
// when
let res1 = bytes1.write(1, &[1, 1, 1]);
let res2 = bytes2.write(3, &[1, 1, 1]);
let res3 = bytes3.write(5, &[1, 1, 1]);
(res1, res2, res3)
};
// then
assert_eq!(&data1, &[0, 1, 1, 1]);
assert_eq!(res1, 3);
assert_eq!(&data2, &[0, 0, 0, 1, 1, 1]);
assert_eq!(res2, 3);
assert_eq!(&data3, &[0, 0, 0, 0, 0, 1, 1, 1]);
assert_eq!(res3, 5);
}
}