From 3f6063b24a603d3327f2a83029a8e9627043d45b Mon Sep 17 00:00:00 2001 From: trivernis Date: Sun, 27 Sep 2020 16:48:43 +0200 Subject: [PATCH] Improve shifting by partial shifting on multiple operations Signed-off-by: trivernis --- Cargo.lock | 2 +- Cargo.toml | 2 +- src/region_file.rs | 62 ++++++++++++++++++++++++++++++++-------------- 3 files changed, 46 insertions(+), 20 deletions(-) diff --git a/Cargo.lock b/Cargo.lock index 838f155..60e25f1 100644 --- a/Cargo.lock +++ b/Cargo.lock @@ -307,7 +307,7 @@ dependencies = [ [[package]] name = "minecraft-regions-tool" -version = "0.5.1" +version = "0.5.2" dependencies = [ "byteorder", "colored", diff --git a/Cargo.toml b/Cargo.toml index 5331e88..29d9bfc 100644 --- a/Cargo.toml +++ b/Cargo.toml @@ -1,6 +1,6 @@ [package] name = "minecraft-regions-tool" -version = "0.5.1" +version = "0.5.2" authors = ["trivernis "] edition = "2018" license = "GPL-3.0" diff --git a/src/region_file.rs b/src/region_file.rs index 96b2845..1176e84 100644 --- a/src/region_file.rs +++ b/src/region_file.rs @@ -96,11 +96,18 @@ impl RegionFile { if options.fix || options.fix_delete { let mut shifted = 0isize; - for (offset, amount) in shift_operations { - let offset = (offset as isize + shifted) as usize; - self.shift_right(offset, amount)?; - self.locations.shift_entries(offset as u32, amount as i32); - shifted += amount; + + let mut operations = shift_operations.iter().peekable(); + while let Some((offset, amount)) = operations.next() { + shifted += *amount; + let end_offset = if let Some((o, a)) = operations.peek() { + (*o as isize + *a) as usize + } else { + self.locations.max_offset() as usize + }; + self.shift_right(*offset, end_offset, shifted)?; + self.locations + .shift_entries(*offset as u32, end_offset as u32, shifted as i32); } statistic.shrunk_size = self.locations.estimated_size(); self.writer.seek(SeekFrom::Start(0))?; @@ -181,16 +188,29 @@ impl RegionFile { } /// Shifts the file from the `offset` position `amount` blocks to the right - pub fn shift_right(&mut self, offset: usize, amount: isize) -> Result<()> { + pub fn shift_right( + &mut self, + start_offset: usize, + end_offset: usize, + amount: isize, + ) -> Result<()> { + log::debug!( + "Shifting chunk blocks starting from {} by {} until {}", + start_offset, + amount, + end_offset, + ); self.reader - .seek(SeekFrom::Start((offset * BLOCK_SIZE) as u64))?; - self.writer.seek(SeekFrom::Start( - ((offset as isize + amount) as usize * BLOCK_SIZE) as u64, - ))?; - loop { + .seek(SeekFrom::Start((start_offset * BLOCK_SIZE) as u64))?; + self.writer + .seek(SeekFrom::Start((start_offset * BLOCK_SIZE) as u64))?; + self.writer + .seek(SeekFrom::Current(amount as i64 * BLOCK_SIZE as i64))?; + for _ in 0..(end_offset - start_offset) { let mut buf = [0u8; BLOCK_SIZE]; let read = self.reader.read(&mut buf)?; self.writer.write(&buf)?; + if read < BLOCK_SIZE { break; } @@ -260,8 +280,8 @@ impl Locations { .collect() } - /// Returns the estimated of all chunks combined including the header - pub fn estimated_size(&self) -> u64 { + /// The maximum offset in the file + pub fn max_offset(&self) -> u32 { let largest = self .inner .iter() @@ -277,7 +297,12 @@ impl Locations { .cloned() .unwrap_or((2, 0)); - (largest.0 as u64 + largest.1 as u64) * BLOCK_SIZE as u64 + largest.0 + largest.1 as u32 + } + + /// Returns the estimated of all chunks combined including the header + pub fn estimated_size(&self) -> u64 { + self.max_offset() as u64 * BLOCK_SIZE as u64 } /// Replaces an entry with a new one. Panics if the index doesn't exist @@ -296,11 +321,12 @@ impl Locations { } /// Shifts all entries starting from `start_index` by `amount` - pub fn shift_entries(&mut self, start_offset: u32, amount: i32) { + pub fn shift_entries(&mut self, start_offset: u32, end_offset: u32, amount: i32) { log::debug!( - "Shifting location entries starting from {} by {}", + "Shifting location entries starting from {} by {} until {}", start_offset, - amount + amount, + end_offset ); self.inner = self .inner @@ -308,7 +334,7 @@ impl Locations { .map(|e| { let mut entry = *e; - if e.0 >= start_offset { + if e.0 >= start_offset && e.0 <= end_offset { entry.0 = (entry.0 as i32 + amount) as u32; }