From 396751d22cc7ce7c2c0477eca5a3248602c6585e Mon Sep 17 00:00:00 2001
From: lixianjing <xianjimli@hotmail.com>
Date: Tue, 1 Oct 2024 18:00:12 +0800
Subject: [PATCH] improve str utils functions

---
 src/tkc/utils.c     | 28 ++++++++++++----------------
 tests/utils_test.cc |  3 +++
 2 files changed, 15 insertions(+), 16 deletions(-)

diff --git a/src/tkc/utils.c b/src/tkc/utils.c
index 6f2565bf6..446d43bca 100644
--- a/src/tkc/utils.c
+++ b/src/tkc/utils.c
@@ -335,9 +335,12 @@ const char* tk_ftoa(char* str, int len, double value) {
 }
 
 char* tk_strcpy(char* dst, const char* src) {
+  return tk_strncpy(dst, src, tk_strlen(src));
+}
+
+char* tk_strncpy(char* dst, const char* src, size_t len) {
   return_value_if_fail(dst != NULL && src != NULL, NULL);
   if (dst != src) {
-    uint32_t len = tk_strlen(src);
     memmove(dst, src, len);
     dst[len] = '\0';
     return dst;
@@ -346,17 +349,6 @@ char* tk_strcpy(char* dst, const char* src) {
   }
 }
 
-char* tk_strncpy(char* dst, const char* src, size_t len) {
-  return_value_if_fail(dst != NULL && src != NULL, NULL);
-
-  if (dst != src) {
-    strncpy(dst, src, len);
-    dst[len] = '\0';
-  }
-
-  return dst;
-}
-
 char* tk_strncpy_s(char* dst, size_t dst_len, const char* src, size_t src_len) {
   size_t len = 0;
   return_value_if_fail(dst != NULL && src != NULL && dst_len > 0, NULL);
@@ -707,10 +699,14 @@ char* tk_str_copy(char* dst, const char* src) {
   if (src != NULL) {
     uint32_t size = tk_strlen(src) + 1;
     if (dst != NULL) {
-      char* str = TKMEM_REALLOCT(char, dst, size);
-      return_value_if_fail(str != NULL, dst);
-      memmove(str, src, size);
-      dst = str;
+      if (dst <= src && src <= dst + tk_strlen(dst)) {
+        tk_strncpy(dst, src, size - 1);
+      } else {
+        char* str = TKMEM_REALLOCT(char, dst, size);
+        return_value_if_fail(str != NULL, dst);
+        memcpy(str, src, size);
+        dst = str;
+      }
     } else {
       char* str = tk_strndup(src, size - 1);
       return_value_if_fail(str != NULL, dst);
diff --git a/tests/utils_test.cc b/tests/utils_test.cc
index a49e28adb..a3000d93f 100644
--- a/tests/utils_test.cc
+++ b/tests/utils_test.cc
@@ -347,6 +347,9 @@ TEST(Utils, tk_strcpy) {
 
   tk_strcpy(str, str + 3);
   ASSERT_STREQ(str, "123");
+
+  tk_strncpy(str + 2, str, 3);
+  ASSERT_STREQ(str, "12123");
 }
 
 TEST(Utils, tk_str_copy) {