[pbs-devel] [PATCH v4 proxmox-backup 24/26] catalog: fetch offset and size for files and refs

[Christian Ebner]

Allows to fetch the pxar archive offsets and file size for regular files
and appendix referenced files.

Signed-off-by: Christian Ebner <c.ebner at proxmox.com>
---
Changes since version 2:
- no present in version 2

 pbs-datastore/src/catalog.rs | 70 ++++++++++++++++++++++++++++++++++++
 1 file changed, 70 insertions(+)

diff --git a/pbs-datastore/src/catalog.rs b/pbs-datastore/src/catalog.rs
index 220313c6..fe076a94 100644
--- a/pbs-datastore/src/catalog.rs
+++ b/pbs-datastore/src/catalog.rs
@@ -1,3 +1,4 @@
+use std::collections::BTreeMap;
 use std::ffi::{CStr, CString, OsStr};
 use std::fmt;
 use std::io::{Read, Seek, SeekFrom, Write};
@@ -1118,6 +1119,75 @@ impl<R: Read + Seek> CatalogReader<R> {
 
         Ok(res)
     }
+
+    /// Get all File and AppendixRef entries with their pxar archive offset and size
+    pub fn fetch_offsets(&mut self) -> Result<BTreeMap<u64, u64>, Error> {
+        let root = self.root()?;
+        let mut list = BTreeMap::new();
+        match root {
+            DirEntry {
+                attr: DirEntryAttribute::Directory { start },
+                ..
+            } => self.fetch_offsets_from_dir(std::path::Path::new("./"), start, &mut list, None)?,
+            _ => bail!("unexpected root entry type, not a directory!"),
+        }
+        Ok(list)
+    }
+
+    fn fetch_offsets_from_dir(
+        &mut self,
+        prefix: &std::path::Path,
+        start: u64,
+        list: &mut BTreeMap<u64, u64>,
+        appendix_start: Option<AppendixStartOffset>,
+    ) -> Result<(), Error> {
+        let data = self.read_raw_dirinfo_block(start)?;
+
+        DirInfo::parse(
+            &data,
+            self.magic,
+            |etype, name_bytes, offset, size, _mtime, _ctime, link_offset| {
+                let mut path = std::path::PathBuf::from(prefix);
+                let name: &OsStr = OsStrExt::from_bytes(name_bytes);
+                path.push(name);
+
+                match etype {
+                    CatalogEntryType::Archive => {
+                        if offset > start {
+                            bail!("got wrong archive offset ({} > {})", offset, start);
+                        }
+                        let pos = start - offset;
+                        let appendix_start = self.appendix_offset(name_bytes)?;
+                        self.fetch_offsets_from_dir(&path, pos, list, appendix_start)?;
+                    }
+                    CatalogEntryType::Directory => {
+                        if offset > start {
+                            bail!("got wrong directory offset ({} > {})", offset, start);
+                        }
+                        let pos = start - offset;
+                        self.fetch_offsets_from_dir(&path, pos, list, appendix_start)?;
+                    }
+                    CatalogEntryType::AppendixRef => {
+                        if let Some(Offset::AppendixRefOffset { offset }) = link_offset {
+                            if let Some(appendix_start) = appendix_start {
+                                list.insert(appendix_start.raw() + offset, size);
+                            } else {
+                                bail!("missing required appendix start offset");
+                            }
+                        }
+                    }
+                    CatalogEntryType::File => {
+                        if let Some(Offset::FileOffset { offset }) = link_offset {
+                            list.insert(offset, size);
+                        }
+                    }
+                    _ => {}
+                }
+                Ok(true)
+            },
+        )?;
+        Ok(())
+    }
 }
 
 /// Serialize i64 as short, variable length byte sequence
-- 
2.39.2