LibC, LibM: Add functions needed to compile python3

Libraries/LibC/wchar.cpp

@@ -1,3 +1,4 @@
+#include <AK/Assertions.h>
 #include <wchar.h>
 
 extern "C" {
@@ -18,6 +19,14 @@ wchar_t* wcscpy(wchar_t* dest, const wchar_t* src)
     return originalDest;
 }
 
+wchar_t* wcsncpy(wchar_t* dest, const wchar_t* src, size_t num)
+{
+    wchar_t* originalDest = dest;
+    while (((*dest++ = *src++) != '\0') && ((size_t)(dest - originalDest) < num))
+        ;
+    return originalDest;
+}
+
 int wcscmp(const wchar_t* s1, const wchar_t* s2)
 {
     while (*s1 == *s2++)
@@ -37,4 +46,79 @@ wchar_t* wcschr(const wchar_t* str, int c)
     }
 }
 
+const wchar_t* wcsrchr(const wchar_t* str, wchar_t wc)
+{
+    wchar_t* last = nullptr;
+    wchar_t c;
+    for (; (c = *str); ++str) {
+        if (c == wc)
+            last = const_cast<wchar_t*>(str);
+    }
+    return last;
+}
+
+wchar_t* wcscat(wchar_t* dest, const wchar_t* src)
+{
+    size_t dest_length = wcslen(dest);
+    size_t i;
+    for (i = 0; src[i] != '\0'; i++)
+        dest[dest_length + i] = src[i];
+    dest[dest_length + i] = '\0';
+    return dest;
+}
+
+wchar_t* wcstok(wchar_t* str, const wchar_t* delim, wchar_t** ptr)
+{
+    wchar_t* used_str = str;
+    if (!used_str) {
+        used_str = *ptr;
+    }
+
+    size_t token_start = 0;
+    size_t token_end = 0;
+    size_t str_len = wcslen(used_str);
+    size_t delim_len = wcslen(delim);
+
+    for (size_t i = 0; i < str_len; ++i) {
+        bool is_proper_delim = false;
+
+        for (size_t j = 0; j < delim_len; ++j) {
+            if (used_str[i] == delim[j]) {
+                // Skip beginning delimiters
+                if (token_end - token_start == 0) {
+                    ++token_start;
+                    break;
+                }
+
+                is_proper_delim = true;
+            }
+        }
+
+        ++token_end;
+        if (is_proper_delim && token_end > 0) {
+            --token_end;
+            break;
+        }
+    }
+
+    if (used_str[token_start] == '\0')
+        return nullptr;
+
+    if (token_end == 0) {
+        return &used_str[token_start];
+    }
+
+    used_str[token_end] = '\0';
+    return &used_str[token_start];
+}
+
+wchar_t* wcsncat(wchar_t* dest, const wchar_t* src, size_t n)
+{
+    size_t dest_length = wcslen(dest);
+    size_t i;
+    for (i = 0; i < n && src[i] != '\0'; i++)
+        dest[dest_length + i] = src[i];
+    dest[dest_length + i] = '\0';
+    return dest;
+}
 }