Restructure project layout and clean up test suite

Move sources to src/, header to inc/, and tests to tests/src/.
Update Makefiles and .gitignore for the new layout.

Refactor test harness: add crash-wrapper macros (_S_CRASH,
_S_CRASH_I, _S_CRASH_V, _S_CRASH_BUF) replacing 58 hand-written
wrappers, add shared _s_test_int_range helper eliminating duplicate
_s_test_func, add _S_RAND_ITERS constant, move srand() to main()
in all test binaries, and add Doxygen comments to test_utils.h.

1 files changed, 19 insertions, 0 deletions

diff --git a/src/ft_calloc.c b/src/ft_calloc.c
new file mode 100644
index 0000000..7726c64
--- /dev/null
+++ b/src/ft_calloc.c
@@ -0,0 +1,19 @@
+#include "libft.h"
+#include <stdlib.h>
+
+void *
+ft_calloc (size_t nmemb, size_t size)
+{
+  void *ptr;
+  size_t total;
+
+  // Detect multiplication overflow before allocating.
+  if (nmemb && size > (size_t)-1 / nmemb)
+    return (NULL);
+  total = nmemb * size;
+  ptr = malloc (total);
+  if (!ptr)
+    return (NULL);
+  ft_bzero (ptr, total);
+  return (ptr);
+}