Merge pull request #47 from JuliaIO/sk/open_read_write

Author: StefanKarpinski

src/Tar.jl

@@ -18,19 +18,36 @@ include("header.jl")
 include("create.jl")
 include("extract.jl")
 
+## some API utilities ##
+
 const true_predicate = _ -> true
 
-open_read(f::Function, tarball::AbstractString) = open(f, tarball)
-open_read(f::Function, tarball::IO) = f(tarball)
+open_read(f::Function, file::AbstractString) = open(f, file)
+open_read(f::Function, file::IO) = f(file)
 
-function open_write(f::Function, tarball::AbstractString)
-    try open(f, tarball, write=true)
+function open_write(f::Function, file::AbstractString)
+    try open(f, file, write=true)
+    catch
+        rm(file, force=true)
+        rethrow()
+    end
+    return file
+end
+function open_write(f::Function, file::Nothing)
+    file, io = mktemp()
+    try f(io)
     catch
-        rm(tarball, force=true)
+        close(io)
+        rm(file, force=true)
         rethrow()
     end
+    close(io)
+    return file
+end
+function open_write(f::Function, file::IO)
+    f(file)
+    return file
 end
-open_write(f::Function, tarball::IO) = f(tarball)
 
 ## official API: create, list, extract
 
@@ -55,32 +72,20 @@ will be included in the archive.
 function create(
     predicate::Function,
     dir::AbstractString,
-    tarball::Union{AbstractString, IO},
+    tarball::Union{AbstractString, IO, Nothing} = nothing,
 )
-    create_dir_check(dir)
+    check_create_dir(dir)
     open_write(tarball) do tar
         create_tarball(predicate, tar, dir)
     end
-    return tarball
-end
-
-function create(predicate::Function, dir::AbstractString)
-    create_dir_check(dir)
-    tarball, tar = mktemp()
-    try create_tarball(predicate, tar, dir)
-    catch
-        close(tar)
-        rm(tarball, force=true)
-        rethrow()
-    end
-    close(tar)
-    return tarball
 end
 
-create(dir::AbstractString, tarball::Union{AbstractString, IO}) =
+function create(
+    dir::AbstractString,
+    tarball::Union{AbstractString, IO, Nothing} = nothing,
+)
     create(true_predicate, dir, tarball)
-create(dir::AbstractString) =
-    create(true_predicate, dir)
+end
 
 """
     list(tarball; [ strict = true ]) -> Vector{Header}
@@ -134,46 +139,35 @@ what is extracted during the extraction process.
 function extract(
     predicate::Function,
     tarball::Union{AbstractString, IO},
-    dir::AbstractString,
+    dir::Union{AbstractString, Nothing} = nothing,
 )
-    extract_tarball_check(tarball)
-    extract_dir_check(dir)
+    check_extract_tarball(tarball)
+    check_extract_dir(dir)
     open_read(tarball) do tar
-        if ispath(dir)
+        if dir !== nothing && ispath(dir)
             extract_tarball(predicate, tar, dir)
         else
-            mkdir(dir)
-            extract_tarball_cleanup_dir(predicate, tar, dir)
+            if dir === nothing
+                dir = mktempdir()
+            else
+                mkdir(dir)
+            end
+            try extract_tarball(predicate, tar, dir)
+            catch
+                chmod(dir, 0o700, recursive=true)
+                rm(dir, force=true, recursive=true)
+                rethrow()
+            end
         end
     end
-    return dir
+    return dir::AbstractString
 end
 
-function extract(predicate::Function, tarball::Union{AbstractString, IO})
-    extract_tarball_check(tarball)
-    open_read(tarball) do tar
-        dir = mktempdir()
-        extract_tarball_cleanup_dir(predicate, tar, dir)
-        return dir
-    end
-end
-
-extract(tarball::Union{AbstractString, IO}, dir::AbstractString) =
-    extract(true_predicate, tarball, dir)
-extract(tarball::Union{AbstractString, IO}) =
-    extract(true_predicate, tarball)
-
-function extract_tarball_cleanup_dir(
-    predicate::Function,
-    tar::IO,
-    dir::AbstractString,
+function extract(
+    tarball::Union{AbstractString, IO},
+    dir::Union{AbstractString, Nothing} = nothing,
 )
-    try extract_tarball(predicate, tar, dir)
-    catch
-        chmod(dir, 0o700, recursive=true)
-        rm(dir, force=true, recursive=true)
-        rethrow()
-    end
+    extract(true_predicate, tarball, dir)
 end
 
 """
@@ -202,48 +196,23 @@ record what content is encountered during the rewrite process.
 function rewrite(
     predicate::Function,
     old_tarball::Union{AbstractString, IO},
-    new_tarball::Union{AbstractString, IO},
+    new_tarball::Union{AbstractString, IO, Nothing} = nothing,
 )
-    old_tarball = rewrite_old_tarball_check(old_tarball)
+    old_tarball = check_rewrite_old_tarball(old_tarball)
     open_read(old_tarball) do old_tar
         open_write(new_tarball) do new_tar
             rewrite_tarball(predicate, old_tar, new_tar)
         end
     end
-    return new_tarball
 end
 
 function rewrite(
-    predicate::Function,
     old_tarball::Union{AbstractString, IO},
-)
-    old_tarball = rewrite_old_tarball_check(old_tarball)
-    open_read(old_tarball) do old_tar
-        new_tarball, new_tar = mktemp()
-        try rewrite_tarball(predicate, old_tar, new_tar)
-        catch
-            close(new_tar)
-            rm(new_tarball, force=true)
-            rethrow()
-        end
-        close(new_tar)
-        return new_tarball
-    end
-end
-
-function rewrite(
-    old_tarball::Union{AbstractString, IO},
-    new_tarball::Union{AbstractString, IO},
+    new_tarball::Union{AbstractString, IO, Nothing} = nothing,
 )
     rewrite(true_predicate, old_tarball, new_tarball)
 end
 
-function rewrite(
-    old_tarball::Union{AbstractString, IO},
-)
-    rewrite(true_predicate, old_tarball)
-end
-
 """
     tree_hash([ predicate, ] tarball;
               [ algorithm = "git-sha1", ]
@@ -305,7 +274,7 @@ function tree_hash(
         algorithm == "git-sha256" ? SHA.SHA256_CTX :
             error("invalid tree hashing algorithm: $algorithm")
 
-    tree_hash_tarball_check(tarball)
+    check_tree_hash_tarball(tarball)
     open_read(tarball) do tar
         git_tree_hash(predicate, tar, HashType, skip_empty)
     end
@@ -316,32 +285,37 @@ function tree_hash(
     algorithm::AbstractString = "git-sha1",
     skip_empty::Bool = false,
 )
-    tree_hash(true_predicate, tarball, algorithm=algorithm, skip_empty=skip_empty)
+    tree_hash(
+        true_predicate,
+        tarball,
+        algorithm = algorithm,
+        skip_empty = skip_empty,
+    )
 end
 
 ## error checking utility functions
 
-create_dir_check(dir::AbstractString) =
+check_create_dir(dir::AbstractString) =
     isdir(dir) || error("""
     not a directory: $dir
     USAGE: create([predicate,] dir, [tarball])
     """)
 
-list_tarball_check(tarball::AbstractString) =
+check_list_tarball(tarball::AbstractString) =
     isfile(tarball) || error("""
     not a file: $tarball
     USAGE: list(tarball)
     """)
 
-extract_tarball_check(tarball::AbstractString) =
+check_extract_tarball(tarball::AbstractString) =
     isfile(tarball) || error("""
     not a file: $tarball
     USAGE: extract([predicate,] tarball, [dir])
     """)
 
-extract_tarball_check(tarball::IO) = nothing
+check_extract_tarball(tarball::IO) = nothing
 
-function extract_dir_check(dir::AbstractString)
+function check_extract_dir(dir::AbstractString)
     st = stat(dir)
     ispath(st) && !isdir(st) &&
         error("""
@@ -355,21 +329,23 @@ function extract_dir_check(dir::AbstractString)
         """)
 end
 
-rewrite_old_tarball_check(tarball::AbstractString) =
+check_extract_dir(dir::Nothing) = nothing
+
+check_rewrite_old_tarball(tarball::AbstractString) =
     isfile(tarball) ? tarball : rror("""
     not a file: $tarball
     USAGE: rewrite([predicate,] old_tarball, [new_tarball])
     """)
 
-rewrite_old_tarball_check(tarball::IO) =
+check_rewrite_old_tarball(tarball::IO) =
     applicable(seek, tarball, 0) ? tarball : IOBuffer(read(tarball))
 
-tree_hash_tarball_check(tarball::AbstractString) =
+check_tree_hash_tarball(tarball::AbstractString) =
     isfile(tarball) || error("""
     not a file: $tarball
     USAGE: tree_hash([predicate,] tarball)
     """)
 
-tree_hash_tarball_check(tarball::IO) = nothing
+check_tree_hash_tarball(tarball::IO) = nothing
 
 end # module