Reuse last used compressor

src/constants.jl

@@ -11,7 +11,6 @@ const Deflate64 = UInt16(9)
 see https://github.com/madler/zipflow/blob/2bef2123ebe519c17b18d2d0c3c71065088de952/zipflow.c#L214
 =#
 function deflate_level_bits(level::Int)::UInt16
-    @argcheck level ∈ (-1:9)
     if level == 9
         0b010 # Maximum
     elseif level == 2

src/types.jl

@@ -79,6 +79,9 @@ mutable struct ZipWriter{S<:IO} <: IO
     used_stripped_dir_names::Set{String}
     check_names::Bool
     transcoder::Union{Nothing, NoopStream{WriteOffsetTracker{S}}, DeflateCompressorStream{WriteOffsetTracker{S}}}
+
+    "Cached codec and compression level to avoid allocations"
+    compressor_cache::Union{Nothing, Tuple{DeflateCompressor, Int}}
     function ZipWriter(io::IO;
             check_names::Bool=true,
             own_io::Bool=false,
@@ -97,6 +100,7 @@ mutable struct ZipWriter{S<:IO} <: IO
             Set{String}(),
             check_names,
             nothing,
+            nothing,
         )
     end
 end

src/writer.jl

@@ -208,14 +208,18 @@ function zip_newfile(w::ZipWriter, name::AbstractString;
     else
         Store
     end
-    codec, level_bits = if real_compression_method==Store
+    codec, level_bits = if real_compression_method == Store
         (Noop(), UInt16(0))
-    elseif real_compression_method==Deflate
+    elseif real_compression_method == Deflate
         @argcheck compression_level ∈ (-1:9)
-        (
-            DeflateCompressor(;level = compression_level),
-            deflate_level_bits(compression_level),
-        )
+        old_compressor_cache = w.compressor_cache
+        if isnothing(old_compressor_cache) || old_compressor_cache[2] != compression_level
+            deflate_codec = DeflateCompressor(;level = compression_level)
+            w.compressor_cache = (deflate_codec, compression_level)
+        else
+            deflate_codec = something(old_compressor_cache)[1]
+        end
+        (deflate_codec, deflate_level_bits(compression_level))
     else
         throw(ArgumentError("compression_method must be Deflate or Store"))
     end
@@ -273,7 +277,6 @@ Base.write(w::ZipWriter, x::UInt8) = write(w, Ref(x))
 
 # WriteOffsetTracker
 Base.isopen(w::WriteOffsetTracker) = !w.bad
-Base.close(w::WriteOffsetTracker) = nothing # this protects the underlying stream from being closed by TranscodingStreams
 Base.isreadable(w::WriteOffsetTracker) = false
 Base.write(w::WriteOffsetTracker, x::UInt8) = write(w, Ref(x))
 
@@ -330,14 +333,9 @@ function zip_commitfile(w::ZipWriter)
         # If some error happens, the file will be partially written,
         # but not included in the central directory.
         # Finish the compressing here, but don't close underlying IO.
-        try
-            write(transcoder, TranscodingStreams.TOKEN_END)
-            # early exit incase io is broken
-            w._io.bad && throw_bad_io()
-        finally
-            # Prevent memory leak maybe.
-            close(transcoder)
-        end
+        write(transcoder, TranscodingStreams.TOKEN_END)
+        # early exit incase io is broken
+        w._io.bad && throw_bad_io()
         cur_offset = w._io.offset
         pe.compressed_size = cur_offset - pe.offset - pe.local_header_size
 
@@ -382,12 +380,7 @@ function zip_abortfile(w::ZipWriter)
         w.transcoder = nothing
         w.partial_entry = nothing
         # Finish the compressing here, but don't close underlying IO.
-        try
-            write(transcoder, TranscodingStreams.TOKEN_END)
-        finally
-            # Prevent memory leak maybe.
-            close(transcoder)
-        end
+        write(transcoder, TranscodingStreams.TOKEN_END)
     end
     nothing
 end
@@ -518,6 +511,7 @@ function Base.close(w::ZipWriter)
             zip_commitfile(w)
         finally
             w.partial_entry = nothing
+            w.compressor_cache = nothing
             try
                 write_footer(w._io, w.entries, w.central_dir_buffer; w.force_zip64)
             finally

test/test_writer.jl

@@ -123,14 +123,14 @@ include("external_unzippers.jl")
     end
 end
 
-if VERSION ≥ v"1.7.0" # ZipStreams requires julia 1.7
+if VERSION ≥ v"1.11.0" # ZipStreams requires julia 1.11
     @testset "Writer compat with ZipStreams" begin
         # setup test env for ZipStreams
         worker = Malt.Worker()
         Malt.remote_eval_fetch(worker, quote
             import Pkg
             Pkg.activate(;temp=true)
-            Pkg.add(name="ZipStreams", version="2.2.0")
+            Pkg.add(name="ZipStreams", version="3.0.0")
             import ZipStreams
             nothing
         end)
@@ -140,7 +140,7 @@ if VERSION ≥ v"1.7.0" # ZipStreams requires julia 1.7
             dir = ZipReader(read(zippath))
             Malt.remote_eval_fetch(worker, quote
                 ZipStreams.zipsource($(zippath)) do zs
-                    ZipStreams.validate(zs)
+                    ZipStreams.is_valid!(zs) || error("archive not valid")
                 end
                 nothing
             end)
@@ -151,7 +151,7 @@ if VERSION ≥ v"1.7.0" # ZipStreams requires julia 1.7
             for i in 1:zip_nentries(dir)
                 name, data = Malt.remote_eval_fetch(worker, quote
                     f = ZipStreams.next_file(zs)
-                    (f.info.name, read(f,String))
+                    (ZipStreams.info(f).name, read(f,String))
                 end)
                 @test zip_readentry(dir, name, String) == data
             end