From 406ed5efac68af31c3cc7a0e7401ebf4dd419804 Mon Sep 17 00:00:00 2001
From: ShadowNinja <shadowninja@minetest.net>
Date: Sun, 14 Sep 2014 17:42:08 -0400
Subject: [PATCH] Add compression API
---
doc/lua_api.txt | 12 ++++++++++
src/script/lua_api/l_util.cpp | 41 +++++++++++++++++++++++++++++++++++
src/script/lua_api/l_util.h | 6 +++++
src/serialization.cpp | 9 ++++----
src/serialization.h | 4 ++--
5 files changed, 65 insertions(+), 7 deletions(-)
diff --git a/doc/lua_api.txt b/doc/lua_api.txt
index 37477b60a..805b63f6a 100644
--- a/doc/lua_api.txt
+++ b/doc/lua_api.txt
@@ -1763,6 +1763,18 @@ minetest.deserialize(string) -> table
^ Example: deserialize('return { ["foo"] = "bar" }') -> {foo='bar'}
^ Example: deserialize('print("foo")') -> nil (function call fails)
^ error:[string "print("foo")"]:1: attempt to call global 'print' (a nil value)
+minetest.compress(data, method, ...) -> compressed_data
+^ Compress a string of data.
+^ `method` is a string identifying the compression method to be used.
+^ Supported compression methods:
+^ Deflate (zlib): "deflate"
+^ `...` indicates method-specific arguments. Currently defined arguments are:
+^ Deflate: `level` - Compression level, 0-9 or nil.
+minetest.decompress(compressed_data, method, ...) -> data
+^ Decompress a string of data (using ZLib).
+^ See documentation on minetest.compress() for supported compression methods.
+^ currently supported.
+^ `...` indicates method-specific arguments. Currently, no methods use this.
minetest.is_protected(pos, name) -> bool
^ This function should be overridden by protection mods and should be used to
check if a player can interact at a position.
diff --git a/src/script/lua_api/l_util.cpp b/src/script/lua_api/l_util.cpp
index 57db632c9..dda5b5abf 100644
--- a/src/script/lua_api/l_util.cpp
+++ b/src/script/lua_api/l_util.cpp
@@ -22,6 +22,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
#include "common/c_converter.h"
#include "common/c_content.h"
#include "cpp_api/s_async.h"
+#include "serialization.h"
#include "debug.h"
#include "porting.h"
#include "log.h"
@@ -283,6 +284,40 @@ int ModApiUtil::l_get_builtin_path(lua_State *L)
return 1;
}
+// compress(data, method, level)
+int ModApiUtil::l_compress(lua_State *L)
+{
+ size_t size;
+ const char *data = luaL_checklstring(L, 1, &size);
+
+ int level = -1;
+ if (!lua_isnone(L, 3) && !lua_isnil(L, 3))
+ level = luaL_checknumber(L, 3);
+
+ std::ostringstream os;
+ compressZlib(std::string(data, size), os, level);
+
+ std::string out = os.str();
+
+ lua_pushlstring(L, out.data(), out.size());
+ return 1;
+}
+
+// decompress(data, method)
+int ModApiUtil::l_decompress(lua_State *L)
+{
+ size_t size;
+ const char * data = luaL_checklstring(L, 1, &size);
+
+ std::istringstream is(std::string(data, size));
+ std::ostringstream os;
+ decompressZlib(is, os);
+
+ std::string out = os.str();
+
+ lua_pushlstring(L, out.data(), out.size());
+ return 1;
+}
void ModApiUtil::Initialize(lua_State *L, int top)
{
@@ -306,6 +341,9 @@ void ModApiUtil::Initialize(lua_State *L, int top)
API_FCT(is_yes);
API_FCT(get_builtin_path);
+
+ API_FCT(compress);
+ API_FCT(decompress);
}
void ModApiUtil::InitializeAsync(AsyncEngine& engine)
@@ -325,5 +363,8 @@ void ModApiUtil::InitializeAsync(AsyncEngine& engine)
ASYNC_API_FCT(is_yes);
ASYNC_API_FCT(get_builtin_path);
+
+ ASYNC_API_FCT(compress);
+ ASYNC_API_FCT(decompress);
}
diff --git a/src/script/lua_api/l_util.h b/src/script/lua_api/l_util.h
index cfdeea1e8..e82432381 100644
--- a/src/script/lua_api/l_util.h
+++ b/src/script/lua_api/l_util.h
@@ -81,6 +81,12 @@ class ModApiUtil : public ModApiBase {
// get_scriptdir()
static int l_get_builtin_path(lua_State *L);
+ // compress(data, method, ...)
+ static int l_compress(lua_State *L);
+
+ // decompress(data, method, ...)
+ static int l_decompress(lua_State *L);
+
public:
static void Initialize(lua_State *L, int top);
diff --git a/src/serialization.cpp b/src/serialization.cpp
index 118bad467..c0fbe10e2 100644
--- a/src/serialization.cpp
+++ b/src/serialization.cpp
@@ -53,7 +53,7 @@ void zerr(int ret)
}
}
-void compressZlib(SharedBuffer<u8> data, std::ostream &os)
+void compressZlib(SharedBuffer<u8> data, std::ostream &os, int level)
{
z_stream z;
const s32 bufsize = 16384;
@@ -65,7 +65,7 @@ void compressZlib(SharedBuffer<u8> data, std::ostream &os)
z.zfree = Z_NULL;
z.opaque = Z_NULL;
- ret = deflateInit(&z, -1);
+ ret = deflateInit(&z, level);
if(ret != Z_OK)
throw SerializationError("compressZlib: deflateInit failed");
@@ -94,13 +94,12 @@ void compressZlib(SharedBuffer<u8> data, std::ostream &os)
}
deflateEnd(&z);
-
}
-void compressZlib(const std::string &data, std::ostream &os)
+void compressZlib(const std::string &data, std::ostream &os, int level)
{
SharedBuffer<u8> databuf((u8*)data.c_str(), data.size());
- compressZlib(databuf, os);
+ compressZlib(databuf, os, level);
}
void decompressZlib(std::istream &is, std::ostream &os)
diff --git a/src/serialization.h b/src/serialization.h
index 86da31486..41a505455 100644
--- a/src/serialization.h
+++ b/src/serialization.h
@@ -78,8 +78,8 @@ with this program; if not, write to the Free Software Foundation, Inc.,
Misc. serialization functions
*/
-void compressZlib(SharedBuffer<u8> data, std::ostream &os);
-void compressZlib(const std::string &data, std::ostream &os);
+void compressZlib(SharedBuffer<u8> data, std::ostream &os, int level = -1);
+void compressZlib(const std::string &data, std::ostream &os, int level = -1);
void decompressZlib(std::istream &is, std::ostream &os);
// These choose between zlib and a self-made one according to version
--
GitLab