[ruby-dev:25318] Re: Zlib memory leak ([ruby-list:39235])

なかだです。

At Fri, 24 Dec 2004 21:34:27 +0900,
sheepman wrote in [ruby-dev:25309]:
> [ruby-list:39235] で報告した Zlib のメモリリークに対するパッチを書いてみました。

見落としてました。

こういう場合、GCに任せるよりもその場で解放してしまったほうがい
いような気もします。


* ext/zlib/zlib.c (rb_deflate_s_deflate, rb_inflate_s_inflate): ensure
  freeing internal zstreams.  fixed: [ruby-dev:25309]

* ext/zlib/zlib.c (rb_deflate_init_copy): replace rb_deflate_clone.


Index: ext/zlib/zlib.c
===================================================================
RCS file: /cvs/ruby/src/ruby/ext/zlib/zlib.c,v
retrieving revision 1.24
diff -U2 -p -r1.24 zlib.c
--- ext/zlib/zlib.c	18 Dec 2004 07:36:33 -0000	1.24
+++ ext/zlib/zlib.c	25 Dec 2004 05:20:59 -0000
@@ -56,5 +56,5 @@ static void zstream_passthrough_input _(
 static VALUE zstream_detach_input _((struct zstream*));
 static void zstream_reset _((struct zstream*));
-static void zstream_end _((struct zstream*));
+static VALUE zstream_end _((struct zstream*));
 static void zstream_run _((struct zstream*, Bytef*, uInt, int));
 static VALUE zstream_sync _((struct zstream*, Bytef*, uInt));
@@ -81,5 +81,6 @@ static VALUE rb_zstream_closed_p _((VALU
 static VALUE rb_deflate_s_allocate _((VALUE));
 static VALUE rb_deflate_initialize _((int, VALUE*, VALUE));
-static VALUE rb_deflate_clone _((VALUE));
+static VALUE rb_deflate_init_copy _((VALUE, VALUE));
+static VALUE deflate_run _((VALUE));
 static VALUE rb_deflate_s_deflate _((int, VALUE*, VALUE));
 static void do_deflate _((struct zstream*, VALUE, int));
@@ -90,4 +91,5 @@ static VALUE rb_deflate_params _((VALUE,
 static VALUE rb_deflate_set_dictionary _((VALUE, VALUE));
 
+static VALUE inflate_run _((VALUE));
 static VALUE rb_inflate_s_allocate _((VALUE));
 static VALUE rb_inflate_initialize _((int, VALUE*, VALUE));
@@ -671,5 +673,5 @@ zstream_reset(z)
 }
 
-static void
+static VALUE
 zstream_end(z)
     struct zstream *z;
@@ -696,4 +698,5 @@ zstream_end(z)
     }
     z->flags = 0;
+    return Qnil;
 }
 
@@ -1156,24 +1159,29 @@ rb_deflate_initialize(argc, argv, obj)
  */
 static VALUE
-rb_deflate_clone(obj)
-    VALUE obj;
+rb_deflate_init_copy(self, orig)
+    VALUE self, orig;
 {
-    struct zstream *z = get_zstream(obj);
-    struct zstream *z2;
-    VALUE clone;
+    struct zstream *z1 = get_zstream(self);
+    struct zstream *z2 = get_zstream(orig);
     int err;
 
-    clone = zstream_deflate_new(rb_class_of(obj));
-    Data_Get_Struct(clone, struct zstream, z2);
-
-    err = deflateCopy(&z2->stream, &z->stream);
+    err = deflateCopy(&z1->stream, &z2->stream);
     if (err != Z_OK) {
 	raise_zlib_error(err, 0);
     }
+    z1->flags = z2->flags;
 
-    z2->flags = z->flags;
-    CLONESETUP(clone, obj);
-    OBJ_INFECT(clone, obj);
-    return clone;
+    return self;
+}
+
+static VALUE
+deflate_run(args)
+    VALUE args;
+{
+    struct zstream *z = (struct zstream *)((VALUE *)args)[0];
+    VALUE src = ((VALUE *)args)[1];
+
+    zstream_run(z, RSTRING(src)->ptr, RSTRING(src)->len, Z_FINISH);
+    return zstream_detach_buffer(z);
 }
 
@@ -1205,5 +1213,5 @@ rb_deflate_s_deflate(argc, argv, klass)
 {
     struct zstream z;
-    VALUE src, level, dst;
+    VALUE src, level, dst, args[2];
     int err, lev;
 
@@ -1219,7 +1227,7 @@ rb_deflate_s_deflate(argc, argv, klass)
     ZSTREAM_READY(&z);
 
-    zstream_run(&z, RSTRING(src)->ptr, RSTRING(src)->len, Z_FINISH);
-    dst = zstream_detach_buffer(&z);
-    zstream_end(&z);
+    args[0] = (VALUE)&z;
+    args[1] = src;
+    dst = rb_ensure(deflate_run, (VALUE)args, zstream_end, (VALUE)&z);
 
     OBJ_INFECT(dst, src);
@@ -1434,4 +1442,16 @@ rb_inflate_initialize(argc, argv, obj)
 }
 
+static VALUE
+inflate_run(args)
+    VALUE args;
+{
+    struct zstream *z = (struct zstream *)((VALUE *)args)[0];
+    VALUE src = ((VALUE *)args)[1];
+
+    zstream_run(z, RSTRING(src)->ptr, RSTRING(src)->len, Z_SYNC_FLUSH);
+    zstream_run(z, "", 0, Z_FINISH);  /* for checking errors */
+    return zstream_detach_buffer(z);
+}
+
 /*
  * call-seq: Zlib::Inflate.inflate(string)
@@ -1456,5 +1476,5 @@ rb_inflate_s_inflate(obj, src)
 {
     struct zstream z;
-    VALUE dst;
+    VALUE dst, args[2];
     int err;
 
@@ -1467,8 +1487,7 @@ rb_inflate_s_inflate(obj, src)
     ZSTREAM_READY(&z);
 
-    zstream_run(&z, RSTRING(src)->ptr, RSTRING(src)->len, Z_SYNC_FLUSH);
-    zstream_run(&z, "", 0, Z_FINISH);  /* for checking errors */
-    dst = zstream_detach_buffer(&z);
-    zstream_end(&z);
+    args[0] = (VALUE)&z;
+    args[1] = src;
+    dst = rb_ensure(inflate_run, (VALUE)args, zstream_end, (VALUE)&z);
 
     OBJ_INFECT(dst, src);
@@ -3439,5 +3458,5 @@ void Init_zlib()
     rb_define_alloc_func(cDeflate, rb_deflate_s_allocate);
     rb_define_method(cDeflate, "initialize", rb_deflate_initialize, -1);
-    rb_define_method(cDeflate, "clone", rb_deflate_clone, 0);
+    rb_define_method(cDeflate, "initialize_copy", rb_deflate_init_copy, 0);
     rb_define_method(cDeflate, "deflate", rb_deflate_deflate, -1);
     rb_define_method(cDeflate, "<<", rb_deflate_addstr, 1);


-- 
--- 僕の前にBugはない。
--- 僕の後ろにBugはできる。
    中田 伸悦