add function strbuff_revert

README.md

@@ -60,7 +60,7 @@ You now have access to all the functions below:
 
 * **strbuff_find(buff, src)** 
 
-* **strbuff_revert(buff)** *not yet implemented*
+* **strbuff_revert(buff)**
 
 * **strbuff_capacity(buff)**
 * **strbuff_len(buff)**

src/strbuff.h

@@ -24,7 +24,7 @@ extern "C" {
 
 #define STRBUFF_VERSION_MAJOR 0
 #define STRBUFF_VERSION_MINOR 1
-#define STRBUFF_VERSION_BUILD 0
+#define STRBUFF_VERSION_BUILD 1
 #define STRBUFF_VERSION       ((STRBUFF_VERSION_MAJOR << 16) | (STRBUFF_VERSION_MINOR << 8) | STRBUFF_VERSION_BUILD)
 
 #ifndef strbuff_error_printf
@@ -153,6 +153,14 @@ char *strbuff_find(const strbuff *dest, const strbuff *substring);
  */
 size_t strbuff_len(const strbuff *buff);
 
+/**
+ * Reverses the contents of a string buffer.
+ *
+ * @param buff Pointer to the string buffer to be reversed.
+ * @return The length of the string buffer.
+ */
+unsigned long strbuff_revert(const strbuff *buff);
+
 /**
  * @brief Sanitizes a string buffer by setting remaining characters (beyond AZT) to 0.
  *

src/strbuff_revert.c

@@ -0,0 +1,32 @@
+// ==========================================
+//   String Buffer Project - A safe string library for C
+//   Copyright (c) 2023 Alex Fabre
+//   [Released under MIT License. Please refer to license.txt for details]
+// ==========================================
+
+#include "strbuff.h"
+
+/**
+ * Reverses the contents of a string buffer.
+ *
+ * @param buff Pointer to the string buffer to be reversed.
+ * @return The length of the string buffer.
+ */
+unsigned long strbuff_revert(const strbuff *buff)
+{
+    strbuff_check_not_null(buff, return 0);
+
+    size_t _buff_len = strbuff_len(buff);
+
+    // Reverse the characters in the buffer one by one
+    for (size_t i = 0; i < (_buff_len / 2); i++) {
+
+        char tmp = *(buff->str + i);
+
+        *(buff->str + i) = *(buff->str + _buff_len - i - 1);
+
+        *(buff->str + _buff_len - 1 - i) = tmp;
+    }
+
+    return _buff_len;
+}

test/test_strbuff.c

@@ -129,6 +129,7 @@ int main(void)
         test_strbuff_len();
         test_strbuff_printc();
         test_strbuff_prints();
+        test_strbuff_revert();
         test_strbuff_sanitize();
     }
 

test/test_strbuff.h

@@ -78,4 +78,5 @@ void test_strbuff_find(void);
 void test_strbuff_printc(void);
 void test_strbuff_prints(void);
 void test_strbuff_len(void);
+void test_strbuff_revert(void);
 void test_strbuff_sanitize(void);

test/test_strbuff_revert.c

@@ -0,0 +1,38 @@
+// ==========================================
+//   String Buffer Project - A safe string library for C
+//   Copyright (c) 2023 Alex Fabre
+//   [Released under MIT License. Please refer to license.txt for details]
+// ==========================================
+
+#include "test_strbuff.h"
+
+static void test_strbuff_revert_filled_buffer(void)
+{
+    /* Fill buffer1 with random string ending with null terminating char */
+    rand_string(buffer1.str, strbuff_capacity(&buffer1));
+
+    /* Get the size of the random string */
+    size_t _len = strbuff_len(&buffer1);
+
+    /* Copy buffer1 to buffer2 up to this null terminating char*/
+    memcpy(buffer2.str, buffer1.str, _len + 1);
+
+    TEST_ASSERT_EQUAL(_len, strbuff_revert(&buffer1));
+    TEST_ASSERT_EQUAL(_len, strbuff_revert(&buffer1));
+    TEST_ASSERT_EQUAL(memcmp(buffer1.str, buffer2.str, _len), 0);
+}
+
+static void test_strbuff_revert_full_buffer(void)
+{
+    /* Fill buffer1 with random string not ending with null temrinating char (dummy byte array) */
+    rand_string_fixed_length(buffer1.str, strbuff_capacity(&buffer1), strbuff_capacity(&buffer1));
+    *(buffer1.str + strbuff_capacity(&buffer1) - 1) = rand_char(false);
+
+    TEST_ASSERT_EQUAL(0, strbuff_revert(&buffer1));
+}
+
+void test_strbuff_revert(void)
+{
+    RUN_TEST(test_strbuff_revert_filled_buffer);
+    RUN_TEST(test_strbuff_revert_full_buffer);
+}