From 291c1133df948e2042f412f31670cbf3a5eaadad Mon Sep 17 00:00:00 2001
From: "Viral B. Shah" <ViralBShah@users.noreply.github.com>
Date: Mon, 21 Aug 2023 22:11:33 -0400
Subject: [PATCH] Simplify some of the dispatch messiness in #90 Possible since
 we have os/arch specific wrappers now.

---
 Project.toml |  2 +-
 src/gz.jl    | 32 ++++++--------------------------
 src/zlib.jl  |  2 +-
 3 files changed, 8 insertions(+), 28 deletions(-)

diff --git a/Project.toml b/Project.toml
index 2669da5..92a19f3 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,7 +1,7 @@
 name = "GZip"
 uuid = "92fee26a-97fe-5a0c-ad85-20a5f3185b63"
 authors = ["staticfloat@gmail.com <staticfloat@gmail.com>"]
-version = "0.6.0"
+version = "0.6.1"
 
 [deps]
 Libdl = "8f399da3-3557-5675-b5ff-fb832c97cbdb"
diff --git a/src/gz.jl b/src/gz.jl
index 8c10be9..cb0e63a 100644
--- a/src/gz.jl
+++ b/src/gz.jl
@@ -136,31 +136,11 @@ gzwrite(s::GZipStream, p::Ptr, len::Integer) =
 gzread(s::GZipStream, p::Ptr, len::Integer) =
     @test_gzerror(s, Zlib_h.gzread(s.gz_file, reinterpret(Ptr{Cvoid}, p), Cuint(len)), -1)
 
-global gzbuffer, _gzopen, _gzseek, _gztell, _gzoffset
-
-# Doesn't exist in zlib 1.2.3 or earlier
-if Libdl.dlsym_e(Zlib_jll.libz_handle, :gzbuffer) != C_NULL
-    gzbuffer(gz_file::Zlib_h.gzFile, gz_buf_size::Integer) = Zlib_h.gzbuffer(gz_file, gz_buf_size)
-else
-    gzbuffer(gz_file::Zlib_h.gzFile, gz_buf_size::Integer) = Cint(-1)
-end
+# Needs zlib 1.2.3 or higher (Julia 1.9 has zlib 1.2.13)
+gzbuffer(gz_file::Zlib_h.gzFile, gz_buf_size::Integer) = Zlib_h.gzbuffer(gz_file, gz_buf_size)
 
 #####
 
-# Use 64-bit functions if available
-
-if Libdl.dlsym_e(Zlib_jll.libz_handle, :gzopen64) != C_NULL && (z_off_t_sz == 8 || !Sys.iswindows())
-    const _gzopen = Zlib_h.gzopen64
-    const _gzseek = Zlib_h.gzseek64
-    const _gztell = Zlib_h.gztell64
-    const _gzoffset = Zlib_h.gzoffset64
-else
-    const _gzopen = Zlib_h.gzopen
-    const _gzseek = Zlib_h.gzseek
-    const _gztell = Zlib_h.gztell
-    const _gzoffset = Zlib_h.gzoffset
-end
-
 """
     gzopen(fname::AbstractString, [gzmode::AbstractString, buf_size::Integer])::GZipStream
 
@@ -207,7 +187,7 @@ function gzopen(fname::AbstractString, gzmode::AbstractString, gz_buf_size::Inte
         gzmode *= "b"
     end
 
-    gz_file = _gzopen(fname, gzmode)
+    gz_file = Zlib_h.gzopen(fname, gzmode)
     if gz_file == C_NULL
         errno = unsafe_load(cglobal((:errno, :libc), Cint))
         throw(SystemError("$(fname)", errno))
@@ -306,15 +286,15 @@ function seek(s::GZipStream, n::Integer)
         end
     end
     # Mimic behavior of seek(s::IOStream, n)
-    _gzseek(s.gz_file, Clong(n), SEEK_SET) != -1 || error("seek (gzseek) failed")
+    Zlib_h.gzseek(s.gz_file, Clong(n), SEEK_SET) != -1 || error("seek (gzseek) failed")
 end
 
 # Note: skips bytes within uncompressed data stream
 # Mimic behavior of skip(s::IOStream, n)
 skip(s::GZipStream, n::Integer) =
-    _gzseek(s.gz_file, Clong(n), SEEK_CUR) != -1 || error("skip (gzseek) failed")
+    Zlib_h.gzseek(s.gz_file, Clong(n), SEEK_CUR) != -1 || error("skip (gzseek) failed")
 
-position(s::GZipStream, raw::Bool=false) = raw ? _gzoffset(s.gz_file) : _gztell(s.gz_file)
+position(s::GZipStream, raw::Bool=false) = raw ? Zlib_h.gzoffset(s.gz_file) : Zlib_h.gztell(s.gz_file)
 
 eof(s::GZipStream) = Bool(Zlib_h.gzeof(s.gz_file))
 
diff --git a/src/zlib.jl b/src/zlib.jl
index 436f540..9562172 100644
--- a/src/zlib.jl
+++ b/src/zlib.jl
@@ -48,7 +48,7 @@ const Z_BIG_BUFSIZE = 131072
 # Get compile-time option flags
 const zlib_compile_flags = Zlib_h.zlibCompileFlags()
 const z_off_t_sz = 2 << ((zlib_compile_flags >> 6) & UInt(3))
-if z_off_t_sz == 8 || (!Sys.iswindows() && Libdl.dlsym_e(Zlib_jll.libz_handle, :gzopen64) != C_NULL)
+if z_off_t_sz == 8 || (!Sys.iswindows() && isdefined(GZip.Zlib_h, :gzopen64))
     const ZFileOffset = Int64
 elseif z_off_t_sz == 4
     const ZFileOffset = Int32