Implemented stdlib.h

libc/stdlib/sort.c

@@ -0,0 +1,37 @@
+#include <stdlib.h>
+#include <stddef.h>
+#include <string.h>
+
+void swap(void* a, void* b, size_t size) {
+    char temp[size];
+    memcpy(temp, a, size);
+    memcpy(a, b, size);
+    memcpy(b, temp, size);
+}
+
+void* partition(void* base, size_t nitem, size_t size, int (*compar)(const void*, const void*)) {
+    char* pivot = (char*)base + (nitem - 1) * size;
+    char* i = (char*)base;
+
+    for (char* j = (char*)base; j < pivot; j += size) {
+        if (compar(j, pivot) < 0) {
+            swap(i, j, size);
+            i += size;
+        }
+    }
+
+    swap(i, pivot, size);
+    return i;
+}
+
+void qsort(void* base, size_t nitem, size_t size, int (*compar)(const void*, const void*)) {
+    if (nitem <= 1) { return; }
+
+    char* pivot = (char*)partition(base, nitem, size, compar);
+    size_t lsize = (pivot - (char*)base) / size;
+    size_t rsize = nitem - lsize - 1;
+
+    qsort(base, lsize, size, compar);
+    qsort(pivot + size, rsize, size, compar);
+}
+