optimize string.trim using c implemention

3 files changed, 82 insertions, 1 deletions

diff --git a/core/src/xmake/machine.c b/core/src/xmake/machine.c
index 77661a445..ff0758882 100644
--- a/core/src/xmake/machine.c
+++ b/core/src/xmake/machine.c
@@ -129,6 +129,7 @@ tb_int_t xm_winos_registry_query(lua_State* lua);
 #endif
 
 // the string functions
+tb_int_t xm_string_trim(lua_State* lua);
 tb_int_t xm_string_convert(lua_State* lua);
 tb_int_t xm_string_endswith(lua_State* lua);
 tb_int_t xm_string_startswith(lua_State* lua);
@@ -263,7 +264,8 @@ static luaL_Reg const g_hash_functions[] =
 // the string functions
 static luaL_Reg const g_string_functions[] = 
 {
-    { "convert",        xm_string_convert       }
+    { "trim",           xm_string_trim          }
+,   { "convert",        xm_string_convert       }
 ,   { "endswith",       xm_string_endswith      }
 ,   { "startswith",     xm_string_startswith    }
 ,   { tb_null,          tb_null                 }
diff --git a/core/src/xmake/makefile b/core/src/xmake/makefile
index f35becda6..7232e0fd9 100644
--- a/core/src/xmake/makefile
+++ b/core/src/xmake/makefile
@@ -61,6 +61,7 @@ xmake_C_FILES 			+= \
 						path/is_absolute \
 						hash/uuid \
 						hash/sha256 \
+						string/trim \
 						string/convert \
 						string/endswith \
 						string/startswith \
diff --git a/core/src/xmake/string/trim.c b/core/src/xmake/string/trim.c
new file mode 100644
index 000000000..c7cce0168
--- /dev/null
+++ b/core/src/xmake/string/trim.c
@@ -0,0 +1,78 @@
+/*!A cross-platform build utility based on Lua
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 
+ * Copyright (C) 2015 - 2019, TBOOX Open Source Group.
+ *
+ * @author      ruki
+ * @file        trim.c
+ *
+ */
+
+/* //////////////////////////////////////////////////////////////////////////////////////
+ * trace
+ */
+#define TB_TRACE_MODULE_NAME                "trim"
+#define TB_TRACE_MODULE_DEBUG               (0)
+
+/* //////////////////////////////////////////////////////////////////////////////////////
+ * includes
+ */
+#include "prefix.h"
+
+/* //////////////////////////////////////////////////////////////////////////////////////
+ * implementation
+ */
+
+/* trim string 
+ *
+ * @param cstr     the c-string
+ * @param mode     the trim mode, all: 0, left: -1, right: 1
+ */
+tb_int_t xm_string_trim(lua_State* lua)
+{
+    // check
+    tb_assert_and_check_return_val(lua, 0);
+
+    // get the string and trim mode
+    size_t           size = 0;
+    tb_char_t const* cstr = luaL_checklstring(lua, 1, &size);
+    ptrdiff_t        mode = luaL_optinteger(lua, 2, 0);
+    tb_check_return_val(cstr, 0);
+
+    // empty string?
+    if (!size) lua_pushstring(lua, "");
+    else
+    {
+        tb_char_t const* p = cstr;
+        tb_char_t const* e = cstr + size;
+    
+        // trim left?
+        if (mode <= 0) while (p < e && tb_isspace(*p)) p++;
+
+        // trim right
+        if (mode >= 0) 
+        {
+            e--;
+            while (e >= cstr && tb_isspace(*e)) e--;
+            e++;
+        }
+
+        // save trimed string
+        if (e > p) lua_pushlstring(lua, p, e - p);
+        else lua_pushstring(lua, "");
+    }
+
+    // ok
+    return 1;
+}