From 7df710fdb2e9b6376b3201ac6dee9ea6524f6e5f Mon Sep 17 00:00:00 2001
From: Michael Siebert <siebertm85@googlemail.com>
Date: Fri, 9 May 2008 17:22:31 +0200
Subject: Add the possibility to read blob contents in chunks via IO#popen

---
 lib/git/lib.rb    | 20 ++++++++++++++------
 lib/git/object.rb | 14 +++++++++++---
 2 files changed, 25 insertions(+), 9 deletions(-)

(limited to 'lib/git')

diff --git a/lib/git/lib.rb b/lib/git/lib.rb
index 55191fe..033df12 100644
--- a/lib/git/lib.rb
+++ b/lib/git/lib.rb
@@ -166,8 +166,8 @@ module Git
       end
     end
     
-    def object_contents(sha)
-      command('cat-file', ['-p', sha])
+    def object_contents(sha, &block)
+      command('cat-file', ['-p', sha], &block)
     end
 
     def ls_tree(sha)
@@ -596,20 +596,20 @@ module Git
       command(cmd, opts, chdir).split("\n")
     end
     
-    def command(cmd, opts = [], chdir = true)
+    def command(cmd, opts = [], chdir = true, &block)
       ENV['GIT_DIR'] = @git_dir if (@git_dir != ENV['GIT_DIR'])
       ENV['GIT_INDEX_FILE'] = @git_index_file if (@git_index_file != ENV['GIT_INDEX_FILE'])
       ENV['GIT_WORK_TREE'] = @git_work_dir if (@git_work_dir != ENV['GIT_WORK_TREE'])
       path = @git_work_dir || @git_dir || @path
 
       opts = opts.to_a.join(' ')
-      git_cmd = "git #{cmd} #{opts}"
+      git_cmd = "git #{cmd} #{opts} 2>&1"
 
       out = nil
       if chdir && (Dir.getwd != path)
-        Dir.chdir(path) { out = `#{git_cmd} 2>&1`.chomp } 
+        Dir.chdir(path) { out = run_command(git_cmd, &block) } 
       else
-        out = `#{git_cmd} 2>&1`.chomp
+        out = run_command(git_cmd, &block)
       end
       
       if @logger
@@ -626,5 +626,13 @@ module Git
       out
     end
     
+    def run_command(git_cmd, &block)
+      if block_given?
+        IO.popen(git_cmd, &block)
+      else
+        `#{git_cmd}`.chomp
+      end
+    end
+    
   end
 end
diff --git a/lib/git/object.rb b/lib/git/object.rb
index e35060c..5ec24e2 100644
--- a/lib/git/object.rb
+++ b/lib/git/object.rb
@@ -28,9 +28,17 @@ module Git
         @size || @size = @base.lib.object_size(@objectish)
       end
       
-      # caches the contents of this call in memory
-      def contents
-        @contents || @contents = @base.lib.object_contents(@objectish)
+      # get the object's contents
+      # if no block is given, the contents are cached in memory and returned as a string
+      # if a block is given, it yields an IO object (via IO::popen) which could be used to
+      # read a large file in chunks. use this for large files so that they are not held
+      # in memory
+      def contents(&block)
+        if block_given?
+          @base.lib.object_contents(@objectish, &block)
+        else
+          @contents || @contents = @base.lib.object_contents(@objectish)
+        end
       end
       
       def contents_array
-- 
cgit