From 52929cef24703ace37859c24477140c880958b59 Mon Sep 17 00:00:00 2001
From: AmauryBrodu <60550980+AmauryBrodu@users.noreply.github.com>
Date: Wed, 29 Mar 2023 13:17:21 +0200
Subject: [PATCH] added the bitmap, tests still need to be done
---
src/utility/bitmap.rs | 102 ++++++++++++++++++++++++++++++++++++++++++
src/utility/mod.rs | 3 +-
2 files changed, 104 insertions(+), 1 deletion(-)
create mode 100644 src/utility/bitmap.rs
diff --git a/src/utility/bitmap.rs b/src/utility/bitmap.rs
new file mode 100644
index 0000000..a34e5b4
--- /dev/null
+++ b/src/utility/bitmap.rs
@@ -0,0 +1,102 @@
+pub const BITS_IN_BYTE: usize = 8;
+pub const BITS_IN_WORD: usize = 32;
+
+use std::fs::File;
+use std::io::{Cursor, Write, Read};
+
+pub struct BitMap {
+ num_bits: usize,
+ num_words: usize,
+ map: Vec<u32>,
+}
+
+impl BitMap {
+
+ pub fn mark(&mut self, which: usize) {
+ assert!(which >= 0 && which < self.num_bits);
+ self.map[which / BITS_IN_WORD] |= 1 << (which % BITS_IN_WORD);
+ }
+
+ pub fn test(&self, which: usize) -> bool {
+ assert!(which < self.num_bits);
+ (self.map[which / BITS_IN_WORD] & (1 << (which % BITS_IN_WORD))) != 0
+ }
+
+ pub fn find(&mut self) -> i32 {
+ for i in 0..self.num_bits {
+ if !self.test(i) {
+ self.mark(i);
+ return i as i32;
+ }
+ }
+ -1
+ }
+
+ pub fn clear(&mut self, which: usize) {
+ assert!(which < self.num_bits, "index out of range");
+
+ let word_idx = which / BITS_IN_WORD;
+ let bit_idx = which % BITS_IN_WORD;
+ self.map[word_idx] &= !(1 << bit_idx);
+ }
+
+ pub fn num_clear(&self) -> i32 {
+ let mut count = 0;
+ for i in 0..self.num_bits {
+ if !self.test(i) {
+ count += 1;
+ }
+ }
+ count
+ }
+
+ pub fn print(&self) {
+ println!("Bitmap set:");
+ for i in 0..self.num_bits {
+ if self.test(i) {
+ print!("{}, ", i);
+ }
+ }
+ println!();
+ }
+
+
+
+ pub fn fetch_from(&mut self, file_path: &str) -> std::io::Result<&Vec<u32>> {
+ // Ouvre le fichier en mode lecture seule
+ let mut file = File::open(file_path)?;
+
+ // Lit les octets du fichier dans un buffer
+ let mut buffer = vec![0; self.num_words * std::mem::size_of::<u32>()];
+ file.read_exact(&mut buffer)?;
+
+ // Convertit les octets en vecteur de u32
+ self.map = vec![0; self.num_words];
+ for i in 0..self.num_words {
+ let j = i * std::mem::size_of::<u32>();
+ let bytes = [
+ buffer[j], buffer[j+1], buffer[j+2], buffer[j+3]
+ ];
+ self.map[i] = u32::from_le_bytes(bytes);
+ }
+
+ Ok(&self.map)
+ }
+
+ pub fn write_back(&mut self, file_path: &str) -> std::io::Result<()> {
+ // Encapsule le vecteur dans un std::io::Cursor pour l'utiliser comme un std::io::Write
+ let mut cursor = Cursor::new(Vec::<u8>::new());
+ for u32_val in self.map.as_mut_slice() {
+ cursor.write_all(&u32_val.to_le_bytes())?;
+ }
+
+ // Ouvre le fichier en mode écriture
+ let mut file = File::create(file_path)?;
+
+ // Écrit les données dans le fichier
+ file.write_all(&cursor.into_inner())?;
+
+ Ok(())
+ }
+
+}
\ No newline at end of file
diff --git a/src/utility/mod.rs b/src/utility/mod.rs
index 651aed7..6db23f2 100644
--- a/src/utility/mod.rs
+++ b/src/utility/mod.rs
@@ -1 +1,2 @@
-pub mod list;
\ No newline at end of file
+pub mod list;
+pub mod bitmap;
\ No newline at end of file