Initial commit: libft Part 1 with tests and documentation

Reimplements 24 libc functions with Doxygen-documented header
and test suite comparing against libc.

1 files changed, 109 insertions, 0 deletions

diff --git a/tests/test_strlen.c b/tests/test_strlen.c
new file mode 100644
index 0000000..ef569ff
--- /dev/null
+++ b/tests/test_strlen.c
@@ -0,0 +1,109 @@
+#include "../libft.h"
+#include "test_utils.h"
+
+static void
+_s_call_ft_strlen_null (void)
+{
+  _s_sink = ft_strlen (NULL);
+}
+
+static void
+_s_call_strlen_null (void)
+{
+  _s_sink = strlen (NULL);
+}
+
+static void
+_s_test_empty (void)
+{
+  printf ("-- empty string --\n");
+  _s_check_eq ("ft_strlen", ft_strlen (""), 0);
+  _s_check_eq ("libc strlen", strlen (""), 0);
+}
+
+static void
+_s_test_null (void)
+{
+  int ft_crashed;
+  int libc_crashed;
+
+  printf ("-- NULL --\n");
+  ft_crashed = _s_crashes (_s_call_ft_strlen_null);
+  libc_crashed = _s_crashes (_s_call_strlen_null);
+  if (ft_crashed && libc_crashed)
+    {
+      printf ("  PASS both crash on NULL\n");
+      _s_pass++;
+    }
+  else if (ft_crashed == libc_crashed)
+    {
+      printf ("  PASS both behave the same on NULL (no crash)\n");
+      _s_pass++;
+    }
+  else
+    {
+      printf ("  FAIL ft_crashed=%d libc_crashed=%d\n", ft_crashed,
+              libc_crashed);
+      _s_fail++;
+    }
+}
+
+static void
+_s_test_random (int n)
+{
+  int i;
+  int len;
+  char *buf;
+  char label[64];
+
+  printf ("-- %d randomized tests --\n", n);
+  for (i = 0; i < n; i++)
+    {
+      len = rand () % 10000;
+      buf = malloc (len + 1);
+      if (!buf)
+        {
+          printf ("  FAIL malloc\n");
+          _s_fail++;
+          return;
+        }
+      memset (buf, 'A' + (i % 26), len);
+      buf[len] = '\0';
+      snprintf (label, sizeof (label), "random len=%d", len);
+      _s_check_eq (label, ft_strlen (buf), strlen (buf));
+      free (buf);
+    }
+}
+
+static void
+_s_test_large (void)
+{
+  size_t len;
+  char *buf;
+
+  printf ("-- large string (100 MB) --\n");
+  len = 100 * 1024 * 1024;
+  buf = malloc (len + 1);
+  if (!buf)
+    {
+      printf ("  SKIP could not allocate %zu bytes\n", len);
+      return;
+    }
+  memset (buf, 'X', len);
+  buf[len] = '\0';
+  _s_check_eq ("100 MB string", ft_strlen (buf), len);
+  free (buf);
+}
+
+int
+main (void)
+{
+  srand (time (NULL));
+  printf ("=== ft_strlen ===\n");
+  _s_test_empty ();
+  _s_test_null ();
+  _s_test_random (100);
+  _s_test_large ();
+  _s_print_results ();
+  return (_s_fail != 0);
+}