Merge pull request #492 from OpportunityLiu/trim

Custom trim chars

1 files changed, 95 insertions, 29 deletions

diff --git a/core/src/xmake/string/trim.c b/core/src/xmake/string/trim.c
index c7cce0168..1c03e999a 100644
--- a/core/src/xmake/string/trim.c
+++ b/core/src/xmake/string/trim.c
@@ -11,10 +11,10 @@
  * 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
+ * @author      OpportunityLiu
  * @file        trim.c
  *
  */
@@ -31,48 +31,114 @@
 #include "prefix.h"
 
 /* //////////////////////////////////////////////////////////////////////////////////////
+ * privates
+ */
+
+static tb_void_t xm_string_trim_space(tb_char_t const** psstr, tb_char_t const** pestr, tb_int_t mode)
+{
+    // check
+    tb_assert(psstr && pestr && *psstr && *pestr);
+
+    tb_char_t const* p = *psstr;
+    tb_char_t const* e = *pestr;
+
+    // trim left?
+    if (mode <= 0)
+        while (p < e && tb_isspace(*p))
+            p++;
+
+    // trim right
+    if (mode >= 0)
+    {
+        e--;
+        while (e >= p && tb_isspace(*e))
+            e--;
+        e++;
+    }
+
+    // save trimed string
+    *psstr = p;
+    *pestr = e;
+}
+
+static tb_char_t const* xm_string_ltrim(tb_char_t const* sstr, tb_char_t const* estr, tb_char_t const* ctrim, size_t ntrim)
+{
+    // check
+    tb_assert(sstr && estr && ctrim);
+
+    // done
+    tb_char_t const* p = sstr;
+    while (p < estr && tb_strnchr(ctrim, ntrim, *p))
+        p++;
+
+    return p;
+}
+
+static tb_char_t const* xm_string_rtrim(tb_char_t const* sstr, tb_char_t const* estr, tb_char_t const* ctrim, size_t ntrim)
+{
+    // check
+    tb_assert(sstr && estr && ctrim);
+
+    // done
+    tb_char_t const* p = estr - 1;
+    while (p >= sstr && tb_strnchr(ctrim, ntrim, *p))
+        p--;
+
+    return p + 1;
+}
+
+/* //////////////////////////////////////////////////////////////////////////////////////
  * implementation
  */
 
-/* trim string 
+/* trim string
  *
- * @param cstr     the c-string
- * @param mode     the trim mode, all: 0, left: -1, right: 1
+ * @param str            the string
+ * @param trimchars      the chars to trim
+ * @param trimtype       0 to trim left and right, -1 to trim left, 1 to trim right
+ *
+ * @code
+ *      local result = string.trim(str, "\r\n \v\t", 0)
+ *      local result = string.trim(str, "(", -1)
+ * @endcode
  */
 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
+    size_t           lstr, ltrim;
+    tb_char_t const* sstr      = luaL_checklstring(lua, 1, &lstr);
+    tb_char_t const* estr      = sstr + lstr;
+    tb_char_t const* trimchars = luaL_optlstring(lua, 2, "", &ltrim);
+    tb_int_t const   trimtype  = (tb_int_t)luaL_optinteger(lua, 3, 0);
+    do
     {
-        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++;
+        tb_assert_and_check_break(sstr && trimchars);
+        // empty string
+        tb_check_break(lstr != 0);
 
-        // trim right
-        if (mode >= 0) 
+        tb_char_t const* const rsstr = sstr;
+        tb_char_t const* const restr = estr;
+        if (ltrim == 0)
+            xm_string_trim_space(&sstr, &estr, trimtype);
+        else
         {
-            e--;
-            while (e >= cstr && tb_isspace(*e)) e--;
-            e++;
+            // trim chars
+            if (trimtype <= 0) sstr = xm_string_ltrim(sstr, estr, trimchars, ltrim);
+            if (trimtype >= 0) estr = xm_string_rtrim(sstr, estr, trimchars, ltrim);
         }
 
-        // save trimed string
-        if (e > p) lua_pushlstring(lua, p, e - p);
-        else lua_pushstring(lua, "");
-    }
+        // no trimed chars
+        tb_check_break(sstr != rsstr || estr != restr);
+
+        // ok
+        lua_pushlstring(lua, sstr, estr - sstr);
+        return 1;
+
+    } while (0);
 
-    // ok
+    // return orignal value
+    lua_settop(lua, 1);
     return 1;
 }