Initial import

boot/common/lib/string.c

@@ -0,0 +1,128 @@
+/*********************************************************************************/
+/* Module Name:  string.c                                                        */
+/* Project:      AurixOS                                                         */
+/*                                                                               */
+/* Copyright (c) 2024-2025 Jozef Nagy                                            */
+/*                                                                               */
+/* This source is subject to the MIT License.                                    */
+/* See License.txt in the root of this repository.                               */
+/* All other rights reserved.                                                    */
+/*                                                                               */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR    */
+/* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,      */
+/* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE   */
+/* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER        */
+/* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, */
+/* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE */
+/* SOFTWARE.                                                                     */
+/*********************************************************************************/
+
+#include <lib/string.h>
+
+#include <stdint.h>
+#include <stddef.h>
+
+size_t mbstowcs(wchar_t *dest, const char **src, size_t len)
+{
+	char *lsrc = (char *)*src;
+	size_t count = len;
+
+	if (dest == NULL) {
+		return 0;
+	}
+
+	while (count) {
+		if ((*dest = *lsrc) == 0) {
+			lsrc = NULL;
+			break;
+		}
+
+		if (*dest >= 0x80) {
+			return -1;
+		}
+
+		lsrc++;
+		dest++;
+		count--;
+	}
+
+	return len - count;
+}
+
+size_t strlen(const char *str)
+{
+	size_t count = 0;
+
+	if (str == NULL) {
+		return 0;
+	}
+
+	do {
+		count++;
+	} while (str[count] != '\0');
+
+	return count;
+}
+
+char *strcpy(char *dest, const char *src)
+{
+	if (dest == NULL || src == NULL) {
+		return NULL;
+	}
+
+	char *pdest = dest;
+
+	while (*src != '\0') {
+		*dest = *src;
+		dest++;
+		src++;
+	}
+
+	*dest = '\0';
+	return pdest;
+}
+
+void *memset(void *dest, int val, size_t len)
+{
+	unsigned char *ptr = dest;
+	while (len-- > 0) {
+		*ptr++ = (unsigned char)val;
+	}
+	return dest;
+}
+
+void *memcpy(void *dest, void *src, size_t len)
+{
+	char *d = (char *)dest;
+	const char *s = (const char *)src;
+
+	while (len-- > 0) {
+		*d++ = *s++;
+	}
+
+	return dest;
+}
+
+int memcmp(const void *a, const void *b, size_t len)
+{
+	unsigned char *ap = (unsigned char *)a;
+    unsigned char *bp = (unsigned char *)b;
+    int ret = 0;
+
+    if (a == b) {
+        return 0;
+    }
+
+    while (len > 0) {
+        if (*ap != *bp) {
+            ret = (*ap > *bp) ? 1 : -1;
+            break;
+        }
+
+        len--;
+        ap++;
+        bp++;
+    }
+
+    return ret;
+}