Implement libft Part 2 with tests

Add ft_substr, ft_strjoin, ft_strtrim, ft_split, ft_itoa,
ft_strmapi, ft_striteri, ft_putchar_fd, ft_putstr_fd,
ft_putendl_fd, ft_putnbr_fd.

1 files changed, 45 insertions, 0 deletions

diff --git a/src/ft_itoa.c b/src/ft_itoa.c
new file mode 100644
index 0000000..05f3fae
--- /dev/null
+++ b/src/ft_itoa.c
@@ -0,0 +1,45 @@
+#include "libft.h"
+#include <stdlib.h>
+
+static size_t
+_s_numlen (int n)
+{
+  size_t len;
+
+  len = 1;
+  if (n < 0)
+    len++;
+  while (n / 10)
+    {
+      len++;
+      n /= 10;
+    }
+  return (len);
+}
+
+char *
+ft_itoa (int n)
+{
+  size_t len;
+  char *str;
+  unsigned int nb;
+
+  len = _s_numlen (n);
+  str = malloc (len + 1);
+  if (!str)
+    return (NULL);
+  str[len] = '\0';
+  if (n < 0)
+    {
+      str[0] = '-';
+      nb = -n;
+    }
+  else
+    nb = n;
+  while (len > 0 && str[len - 1] != '-')
+    {
+      str[--len] = '0' + nb % 10;
+      nb /= 10;
+    }
+  return (str);
+}