From afdc0f0e42a8a9b81b0da7e83e654f3413d3aba1 Mon Sep 17 00:00:00 2001
From: Christian Ebner <c.ebner@proxmox.com>
Date: Mon, 10 Jun 2024 13:06:21 +0200
Subject: [PATCH] client: pxar: encode prelude based on writer variant

Currently, whether to encode the exlcude patterns passed via cli as
prelude or via the `.pxar-exclude-cli` is based on the presence of
a previous metadata accessor.
That leaves however to the encoding of the file entry instead of the
prelude for split archives in `data` mode and for the first snapshot
in a backup, creating undesired padding in the first payload chunk.

Therefore, use the pxar writer variant to make the decision instead.

Signed-off-by: Christian Ebner <c.ebner@proxmox.com>
---
 pbs-client/src/pxar/create.rs | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/pbs-client/src/pxar/create.rs b/pbs-client/src/pxar/create.rs
index dc0a31e7..9a41bf3e 100644
--- a/pbs-client/src/pxar/create.rs
+++ b/pbs-client/src/pxar/create.rs
@@ -183,6 +183,7 @@ struct Archiver {
     previous_payload_index: Option<DynamicIndexReader>,
     cache: PxarLookaheadCache,
     reuse_stats: ReuseStats,
+    split_archive: bool,
 }
 
 type Encoder<'a, T> = pxar::encoder::aio::Encoder<'a, T>;
@@ -247,7 +248,8 @@ where
         )?);
     }
 
-    let prelude = if options.previous_ref.is_some() && !patterns.is_empty() {
+    let split_archive = writers.archive.payload().is_some();
+    let prelude = if split_archive && !patterns.is_empty() {
         let prelude = PbsClientPrelude {
             exclude_patterns: Some(String::from_utf8(generate_pxar_excludes_cli(
                 &patterns[..],
@@ -258,7 +260,7 @@ where
         None
     };
 
-    let metadata_mode = options.previous_ref.is_some() && writers.archive.payload().is_some();
+    let metadata_mode = options.previous_ref.is_some() && split_archive;
     let (previous_payload_index, previous_metadata_accessor) =
         if let Some(refs) = options.previous_ref {
             (
@@ -291,6 +293,7 @@ where
         previous_payload_index,
         cache: PxarLookaheadCache::new(options.max_cache_size),
         reuse_stats: ReuseStats::default(),
+        split_archive,
     };
 
     archiver
@@ -388,12 +391,11 @@ impl Archiver {
             for file_entry in file_list {
                 let file_name = file_entry.name.to_bytes();
 
-                if is_root
-                    && file_name == b".pxarexclude-cli"
-                    && previous_metadata_accessor.is_none()
-                {
-                    self.encode_pxarexclude_cli(encoder, &file_entry.name, old_patterns_count)
-                        .await?;
+                if is_root && file_name == b".pxarexclude-cli" {
+                    if !self.split_archive {
+                        self.encode_pxarexclude_cli(encoder, &file_entry.name, old_patterns_count)
+                            .await?;
+                    }
                     continue;
                 }
 
@@ -1944,6 +1946,7 @@ mod tests {
                 suggested_boundaries: Some(suggested_boundaries),
                 cache: PxarLookaheadCache::new(None),
                 reuse_stats: ReuseStats::default(),
+                split_archive: true,
             };
 
             let accessor = Accessor::new(pxar::PxarVariant::Unified(reader), metadata_size)