libimagcounter: init

5 files changed, 264 insertions, 0 deletions

diff --git a/libimagcounter/Cargo.toml b/libimagcounter/Cargo.toml
new file mode 100644
index 00000000..15ec9add
--- /dev/null
+++ b/libimagcounter/Cargo.toml
@@ -0,0 +1,13 @@
+[package]
+name = "libimagcounter"
+version = "0.1.0"
+authors = ["Matthias Beyer <mail@beyermatthias.de>"]
+
+[dependencies]
+log = "0.3.5"
+toml = "0.1.25"
+semver = "0.2"
+
+[dependencies.libimagstore]
+path = "../libimagstore"
+
diff --git a/libimagcounter/src/counter.rs b/libimagcounter/src/counter.rs
new file mode 100644
index 00000000..d233e80d
--- /dev/null
+++ b/libimagcounter/src/counter.rs
@@ -0,0 +1,144 @@
+use std::convert::From;
+use std::convert::Into;
+use std::ops::DerefMut;
+use std::ops::Deref;
+
+use toml::Value;
+
+use std::collections::BTreeMap;
+
+use libimagstore::store::Store;
+use libimagstore::store::FileLockEntry;
+use libimagstore::storeid::StoreId;
+use libimagstore::error::StoreError;
+use libimagstore::store::Entry;
+use libimagstore::storeid::IntoStoreId;
+
+use module_path::ModuleEntryPath;
+use result::Result;
+use error::CounterError as CE;
+use error::CounterErrorKind as CEK;
+
+pub type CounterName = String;
+
+pub struct Counter<'a> {
+    fle: FileLockEntry<'a>,
+}
+
+impl<'a> Counter<'a> {
+
+    pub fn new(store: &Store, name: CounterName, init: i64) -> Result<Counter> {
+        use std::ops::DerefMut;
+
+        debug!("Creating new counter: '{}' with value: {}", name, init);
+        let fle = {
+            let mut lockentry = store.create(ModuleEntryPath::new(name.clone()).into_storeid());
+            if lockentry.is_err() {
+                return Err(CE::new(CEK::StoreWriteError, Some(Box::new(lockentry.err().unwrap()))));
+            }
+            let mut lockentry = lockentry.unwrap();
+
+            {
+                let mut entry  = lockentry.deref_mut();
+                let mut header = entry.get_header_mut();
+                let setres = header.set("counter", Value::Table(BTreeMap::new()));
+                if setres.is_err() {
+                    return Err(CE::new(CEK::StoreWriteError, Some(Box::new(setres.err().unwrap()))));
+                }
+
+                let setres = header.set("counter.name", Value::String(name));
+                if setres.is_err() {
+                    return Err(CE::new(CEK::StoreWriteError, Some(Box::new(setres.err().unwrap()))));
+                }
+
+                let setres = header.set("counter.value", Value::Integer(init));
+                if setres.is_err() {
+                    return Err(CE::new(CEK::StoreWriteError, Some(Box::new(setres.err().unwrap()))));
+                }
+            }
+
+            lockentry
+        };
+
+        Ok(Counter { fle: fle })
+    }
+
+    pub fn inc(&mut self) -> Result<()> {
+        let mut header = self.fle.deref_mut().get_header_mut();
+        match header.read("counter.value") {
+            Ok(Some(Value::Integer(i))) => {
+                header.set("counter.value", Value::Integer(i + 1))
+                    .map_err(|e| CE::new(CEK::StoreWriteError, Some(Box::new(e))))
+                    .map(|_| ())
+            },
+            Err(e) => Err(CE::new(CEK::StoreReadError, Some(Box::new(e)))),
+            _ => Err(CE::new(CEK::StoreReadError, None)),
+        }
+    }
+
+    pub fn dec(&mut self) -> Result<()> {
+        let mut header = self.fle.deref_mut().get_header_mut();
+        match header.read("counter.value") {
+            Ok(Some(Value::Integer(i))) => {
+                header.set("counter.value", Value::Integer(i - 1))
+                    .map_err(|e| CE::new(CEK::StoreWriteError, Some(Box::new(e))))
+                    .map(|_| ())
+            },
+            Err(e) => Err(CE::new(CEK::StoreReadError, Some(Box::new(e)))),
+            _ => Err(CE::new(CEK::StoreReadError, None)),
+        }
+    }
+
+    pub fn reset(&mut self) -> Result<()> {
+        let mut header = self.fle.deref_mut().get_header_mut();
+        header.set("counter.value", Value::Integer(0))
+            .map_err(|e| CE::new(CEK::StoreWriteError, Some(Box::new(e))))
+            .map(|_| ())
+    }
+
+    pub fn set(&mut self, v: i64) -> Result<()> {
+        let mut header = self.fle.deref_mut().get_header_mut();
+        header.set("counter.value", Value::Integer(v))
+            .map_err(|e| CE::new(CEK::StoreWriteError, Some(Box::new(e))))
+            .map(|_| ())
+    }
+
+    pub fn name(&self) -> Result<CounterName> {
+        let mut header = self.fle.deref().get_header();
+        header.read("counter.name")
+            .map_err(|e| CE::new(CEK::StoreWriteError, Some(Box::new(e))))
+            .and_then(|v| {
+                match v {
+                    Some(Value::String(s)) => Ok(s),
+                    _ => Err(CE::new(CEK::HeaderTypeError, None)),
+                }
+            })
+    }
+
+    pub fn value(&self) -> Result<i64> {
+        let mut header = self.fle.deref().get_header();
+        header.read("counter.value")
+            .map_err(|e| CE::new(CEK::StoreWriteError, Some(Box::new(e))))
+            .and_then(|v| {
+                match v {
+                    Some(Value::Integer(i)) => Ok(i),
+                    _ => Err(CE::new(CEK::HeaderTypeError, None)),
+                }
+            })
+    }
+
+    pub fn load(name: CounterName, store: &Store) -> Result<Counter> {
+        debug!("Loading counter: '{}'", name);
+        match store.retrieve(ModuleEntryPath::new(name).into_storeid()) {
+            Err(e) => Err(CE::new(CEK::StoreReadError, Some(Box::new(e)))),
+            Ok(c)  => Ok(Counter { fle: c }),
+        }
+    }
+
+    pub fn delete(name: CounterName, store: &Store) -> Result<()> {
+        debug!("Deleting counter: '{}'", name);
+        store.delete(ModuleEntryPath::new(name).into_storeid())
+            .map_err(|e| CE::new(CEK::StoreWriteError, Some(Box::new(e))))
+    }
+}
+
diff --git a/libimagcounter/src/error.rs b/libimagcounter/src/error.rs
new file mode 100644
index 00000000..78d0cf46
--- /dev/null
+++ b/libimagcounter/src/error.rs
@@ -0,0 +1,89 @@
+use std::error::Error;
+use std::fmt::Error as FmtError;
+use std::clone::Clone;
+use std::fmt::{Debug, Display, Formatter};
+use std::fmt;
+use std::convert::From;
+
+/**
+ * Kind of error
+ */
+#[derive(Clone, Copy, Debug, PartialEq)]
+pub enum CounterErrorKind {
+    StoreReadError,
+    StoreWriteError,
+    HeaderTypeError,
+    HeaderFieldMissingError,
+}
+
+fn counter_error_type_as_str(e: &CounterErrorKind) -> &'static str {
+    match e {
+        &CounterErrorKind::StoreReadError  => "Store read error",
+        &CounterErrorKind::StoreWriteError => "Store write error",
+        &CounterErrorKind::HeaderTypeError => "Header type error",
+        &CounterErrorKind::HeaderFieldMissingError => "Header field missing error",
+    }
+}
+
+impl Display for CounterErrorKind {
+
+    fn fmt(&self, fmt: &mut Formatter) -> Result<(), FmtError> {
+        try!(write!(fmt, "{}", counter_error_type_as_str(self)));
+        Ok(())
+    }
+
+}
+
+/**
+ * Store error type
+ */
+#[derive(Debug)]
+pub struct CounterError {
+    err_type: CounterErrorKind,
+    cause: Option<Box<Error>>,
+}
+
+impl CounterError {
+
+    /**
+     * Build a new CounterError from an CounterErrorKind, optionally with cause
+     */
+    pub fn new(errtype: CounterErrorKind, cause: Option<Box<Error>>)
+        -> CounterError
+        {
+            CounterError {
+                err_type: errtype,
+                cause: cause,
+            }
+        }
+
+    /**
+     * Get the error type of this CounterError
+     */
+    pub fn err_type(&self) -> CounterErrorKind {
+        self.err_type.clone()
+    }
+
+}
+
+impl Display for CounterError {
+
+    fn fmt(&self, fmt: &mut Formatter) -> Result<(), FmtError> {
+        try!(write!(fmt, "[{}]", counter_error_type_as_str(&self.err_type.clone())));
+        Ok(())
+    }
+
+}
+
+impl Error for CounterError {
+
+    fn description(&self) -> &str {
+        counter_error_type_as_str(&self.err_type.clone())
+    }
+
+    fn cause(&self) -> Option<&Error> {
+        self.cause.as_ref().map(|e| &**e)
+    }
+
+}
+
diff --git a/libimagcounter/src/lib.rs b/libimagcounter/src/lib.rs
new file mode 100644
index 00000000..8b7a333a
--- /dev/null
+++ b/libimagcounter/src/lib.rs
@@ -0,0 +1,12 @@
+extern crate toml;
+#[macro_use] extern crate log;
+#[macro_use] extern crate semver;
+
+#[macro_use] extern crate libimagstore;
+
+module_entry_path_mod!("counter", "0.1.0");
+
+pub mod counter;
+pub mod error;
+pub mod result;
+
diff --git a/libimagcounter/src/result.rs b/libimagcounter/src/result.rs
new file mode 100644
index 00000000..91a26599
--- /dev/null
+++ b/libimagcounter/src/result.rs
@@ -0,0 +1,6 @@
+use std::result::Result as RResult;
+
+use error::CounterError;
+
+pub type Result<T> = RResult<T, CounterError>;
+