Updated hw6 to a newer version

Signed-off-by: jmug <u.g.a.mariano@gmail.com>

hw6/bin/cinterop.c

@@ -0,0 +1,64 @@
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+
+void ll_puts(int8_t *s) {
+  puts((char *)s);
+}
+
+int8_t* ll_strcat(int8_t* s1, int8_t* s2) {
+  int l1 = strlen((char*)s1);
+  int l2 = strlen((char*)s2);
+  char* buf = (char*)calloc(l1 + l2 + 1, sizeof(char));
+  strncpy(buf, (char*)s1, l1);
+  strncpy(buf + l1, (char*)s2, l2+1);
+  return (int8_t*) buf;
+}
+
+int64_t ll_callback(int64_t (*fun)(int64_t, int64_t)) {
+  int64_t x = 19L;
+  return fun(x, x);
+}
+
+int8_t* ll_ltoa(int64_t i) {
+  // Safety: INT64_MIN is -9223372036854775808, which has 20 characters when
+  // represented as a string. After including the null terminator, we need to
+  // allocate a buffer of size 21.
+  char* buf = (char*)calloc(21, sizeof(char));
+  int t = 0;
+  if (i == 0) {
+    buf[t++] = '0';
+    return (int8_t*) buf;
+  }
+
+  bool negative = i < 0;
+  if (!negative) {
+    // Normalize to negative number to avoid overflow
+    i = -i;
+  }
+
+  // Generate the digits in reverse order, from [0..t)
+  while (i < 0) {
+    char last_digit = '0' + -(i % 10);
+    buf[t++] = last_digit;
+    i /= 10;
+  }
+  if (negative) {
+    buf[t++] = '-';
+  }
+
+  // Reverse the buffer
+  for (int j = 0, r = t - 1; j < r; j++, r--) {
+    char temp = buf[j];
+    buf[j] = buf[r];
+    buf[r] = temp;
+  }
+
+  return (int8_t*) buf;
+}
+
+void *ll_malloc(int64_t n, int64_t size) {
+  return calloc(n, size);
+}