break dependency of programs on solana core (#1371)

* break dependency of programs on Solana core

common/Cargo.toml

@@ -0,0 +1,22 @@
+[package]
+name = "solana_program_interface"
+version = "0.1.0"
+authors = [
+    "Anatoly Yakovenko <anatoly@solana.com>",
+    "Greg Fitzgerald <greg@solana.com>",
+    "Stephen Akridge <stephen@solana.com>",
+    "Michael Vines <mvines@solana.com>",
+    "Rob Walker <rob@solana.com>",
+    "Pankaj Garg <pankaj@solana.com>",
+    "Tyera Eulberg <tyera@solana.com>",
+    "Jack May <jack@solana.com>",
+]
+
+[dependencies]
+bincode = "1.0.0"
+bs58 = "0.2.0"
+generic-array = { version = "0.12.0", default-features = false, features = ["serde"] }
+serde = "1.0.27"
+serde_derive = "1.0.27"
+
+

common/src/account.rs

@@ -0,0 +1,29 @@
+use pubkey::Pubkey;
+
+/// An Account with userdata that is stored on chain
+#[derive(Serialize, Deserialize, Debug, Clone, Default)]
+pub struct Account {
+    /// tokens in the account
+    pub tokens: i64,
+    /// user data
+    /// A transaction can write to its userdata
+    pub userdata: Vec<u8>,
+    /// contract id this contract belongs to
+    pub program_id: Pubkey,
+}
+
+impl Account {
+    pub fn new(tokens: i64, space: usize, program_id: Pubkey) -> Account {
+        Account {
+            tokens,
+            userdata: vec![0u8; space],
+            program_id,
+        }
+    }
+}
+
+#[derive(Debug)]
+pub struct KeyedAccount<'a> {
+    pub key: &'a Pubkey,
+    pub account: &'a mut Account,
+}

common/src/lib.rs

@@ -0,0 +1,7 @@
+pub mod account;
+pub mod pubkey;
+extern crate bincode;
+extern crate bs58;
+extern crate generic_array;
+#[macro_use]
+extern crate serde_derive;

common/src/pubkey.rs

@@ -0,0 +1,31 @@
+use bs58;
+use generic_array::typenum::U32;
+use generic_array::GenericArray;
+use std::fmt;
+
+#[derive(Serialize, Deserialize, Clone, Copy, Default, Eq, PartialEq, Ord, PartialOrd, Hash)]
+pub struct Pubkey(GenericArray<u8, U32>);
+
+impl Pubkey {
+    pub fn new(pubkey_vec: &[u8]) -> Self {
+        Pubkey(GenericArray::clone_from_slice(&pubkey_vec))
+    }
+}
+
+impl AsRef<[u8]> for Pubkey {
+    fn as_ref(&self) -> &[u8] {
+        &self.0[..]
+    }
+}
+
+impl fmt::Debug for Pubkey {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}", bs58::encode(self.0).into_string())
+    }
+}
+
+impl fmt::Display for Pubkey {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}", bs58::encode(self.0).into_string())
+    }
+}