Merge pull request #27 from isbm/isbm-pkglist-dryrun

Add packagelist for the dry-run

src/scanner/debftrace.rs

@@ -0,0 +1,64 @@
+use crate::rootfs::RootFS;
+
+use super::traceitf::PkgFileTrace;
+use std::{
+    collections::HashMap,
+    fs::{self, DirEntry},
+    path::PathBuf,
+};
+
+pub struct DebPkgFileTrace {
+    file_to_pkg: HashMap<PathBuf, String>,
+}
+
+impl DebPkgFileTrace {
+    pub fn new() -> Self {
+        let mut d = DebPkgFileTrace { file_to_pkg: HashMap::default() };
+        d.load();
+        d
+    }
+
+    /// Read dpkg cache. All of it.
+    fn load(&mut self) {
+        if let Ok(rd) = fs::read_dir("/var/lib/dpkg/info") {
+            for d in rd.filter_map(Result::ok).collect::<Vec<DirEntry>>() {
+                if d.path().to_str().unwrap().ends_with(".list") {
+                    self.load_pkg(d.path());
+                }
+            }
+        }
+    }
+
+    fn load_pkg(&mut self, pinfo: PathBuf) {
+        // Path to package name
+        let pkgname = &pinfo
+            .file_name()
+            .unwrap_or_default()
+            .to_str()
+            .unwrap()
+            .strip_suffix(".list")
+            .unwrap()
+            .split(':')
+            .collect::<Vec<&str>>()[0];
+
+        if let Ok(pkg_data) = fs::read_to_string(&pinfo) {
+            for f_pth in pkg_data.split('\n').collect::<Vec<&str>>().iter().map(PathBuf::from) {
+                if f_pth.exists() && f_pth.is_file() {
+                    self.file_to_pkg.insert(f_pth, pkgname.to_string().to_owned());
+                }
+            }
+        }
+    }
+}
+
+impl PkgFileTrace for DebPkgFileTrace {
+    fn trace(&mut self, filename: PathBuf) -> Option<String> {
+        for p in RootFS::expand_target(filename, true) {
+            if let Some(pkg) = self.file_to_pkg.get(&p) {
+                return Some(pkg.to_owned());
+            }
+        }
+
+        None
+    }
+}

src/scanner/dlst.rs

@@ -2,11 +2,15 @@
 Data lister (fancy STDOUT printer)
 */
 
-use crate::filters::resources;
+use crate::{
+    filters::resources,
+    scanner::{debftrace::DebPkgFileTrace, traceitf::PkgFileTrace},
+};
 use bytesize::ByteSize;
 use colored::Colorize;
 use filesize::PathExt;
 use std::{
+    collections::HashSet,
     os::unix::prelude::PermissionsExt,
     path::{Path, PathBuf},
 };
@@ -110,6 +114,17 @@ impl<'a> ContentFormatter<'a> {
             d_size += p.metadata().unwrap().len();
         }
 
+        // Collect preserved packages
+        let mut pkgs: HashSet<String> = HashSet::default();
+        let mut pt = DebPkgFileTrace::new();
+        for p in self.fs_data {
+            if let Some(pkg) = pt.trace(p.clone()) {
+                pkgs.insert(pkg);
+            }
+        }
+        let mut pkgs = pkgs.into_iter().collect::<Vec<String>>();
+        pkgs.sort();
+
         // Print the summary
         println!(
             "\nRemoved {} files, releasing {} of a disk space",
@@ -128,7 +143,7 @@ impl<'a> ContentFormatter<'a> {
                 ByteSize::b(j_size).to_string().bright_yellow()
             );
         }
-        println!("");
+        println!("Kept {} packages as follows:\n  {}\n", pkgs.len().to_string().bright_yellow(), pkgs.join(", "));
     }
 
     /// Get dir/name split, painted accordingly

src/scanner/mod.rs

@@ -1,4 +1,5 @@
 pub mod binlib;
+pub mod debftrace;
 pub mod debpkg;
 pub(crate) mod dlst;
 pub mod general;

src/scanner/traceitf.rs

@@ -1,5 +1,12 @@
+use std::path::PathBuf;
+
 /// Package dependency trace
 pub trait PkgDepTrace {
     fn trace(&mut self, pkgname: String) -> Vec<String>;
     fn exclude(&mut self, pkgs: Vec<String>) -> &mut Self;
 }
+
+pub trait PkgFileTrace {
+    /// Return a package name, to which this file belongs to
+    fn trace(&mut self, filename: PathBuf) -> Option<String>;
+}