From 6f8f9bd75db9413e3cf02338e5116478df0888f9 Mon Sep 17 00:00:00 2001
From: noyez <noyez@ithryn.net>
Date: Fri, 21 Aug 2020 02:42:11 -0400
Subject: [PATCH] Change closure from Fn to FnMut. (#5)

* Using FnMut, so works
* Using FnMut for watch() and reopen_if_log_rotated()
* adding fn to force reopen
* adding actions to closure

Co-authored-by: noyez <brad@bkn.local>
Co-authored-by: noyez <brad@bkn.localdomain>
Co-authored-by: Bradley Noyes <b@noyes.dev>
---
 Cargo.toml  |  2 +-
 src/lib.rs  | 23 ++++++++++++++++++-----
 src/main.rs |  5 +++--
 3 files changed, 22 insertions(+), 8 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index 2743d0c..731252a 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "logwatcher"
-version = "0.1.0"
+version = "0.1.1"
 authors = ["Aravinda VK <mail@aravindavk.in>"]
 
 description = "A lib to watch log files for new Changes, just like tail -f"
diff --git a/src/lib.rs b/src/lib.rs
index 8637090..3833a7e 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -8,6 +8,11 @@ use std::os::unix::fs::MetadataExt;
 use std::thread::sleep;
 use std::time::Duration;
 
+pub enum LogWatcherAction{
+    None,
+    SeekToEnd,
+}
+
 pub struct LogWatcher {
     filename: String,
     inode: u64,
@@ -40,9 +45,9 @@ impl LogWatcher {
         })
     }
 
-    fn reopen_if_log_rotated<F: ?Sized>(&mut self, callback: &F)
+    fn reopen_if_log_rotated<F: ?Sized>(&mut self, callback: &mut F)
     where
-        F: Fn(String),
+        F: FnMut(String) -> LogWatcherAction,
     {
         loop {
             match File::open(self.filename.clone()) {
@@ -78,9 +83,9 @@ impl LogWatcher {
         }
     }
 
-    pub fn watch<F: ?Sized>(&mut self, callback: &F)
+    pub fn watch<F: ?Sized>(&mut self, callback: &mut F)
     where
-        F: Fn(String),
+        F: FnMut(String) -> LogWatcherAction,
     {
         loop {
             let mut line = String::new();
@@ -90,7 +95,15 @@ impl LogWatcher {
                     if len > 0 {
                         self.pos += len as u64;
                         self.reader.seek(SeekFrom::Start(self.pos)).unwrap();
-                        callback(line.replace("\n", ""));
+                        match callback(line.replace("\n", ""))
+                        {
+                            LogWatcherAction::SeekToEnd => {
+                                println!("SeekToEnd");
+                                self.reader.seek(SeekFrom::End(0)).unwrap();
+                            }
+                            LogWatcherAction::None => {
+                            }
+                        }
                         line.clear();
                     } else {
                         if self.finish {
diff --git a/src/main.rs b/src/main.rs
index dfc085e..4f21eee 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -2,7 +2,7 @@ use std::env::args;
 use std::process::exit;
 
 extern crate logwatcher;
-use logwatcher::LogWatcher;
+use logwatcher::{LogWatcher, LogWatcherAction};
 
 fn main() {
     let filename = match args().nth(1) {
@@ -15,7 +15,8 @@ fn main() {
 
     let mut log_watcher = LogWatcher::register(filename).unwrap();
 
-    log_watcher.watch(&|line: String| {
+    log_watcher.watch(&mut move |line: String| {
         println!("Line {}", line);
+        LogWatcherAction::None
     });
 }