base64 without error management done

src/base64/ft_base64_decode_transform.c

@@ -1,9 +1,26 @@
 #include "ft_base64.h"
 #include "libft.h"
 
+static t_byte1 get_alphabet_index
+(
+	t_byte1 *alphabet,
+	t_byte1 ch
+)
+{
+	char *alphabet_addr;
+
+	alphabet_addr = ft_strchr((const char*)alphabet, ch);
+	if (!alphabet_addr)
+	{
+		ft_putstr("base64: invalid input\n");
+		exit(1);
+	}
+	return (alphabet_addr - (char *)alphabet);
+}
+
 void	ft_base64_decode_transform
 (
-	t_base64_ctx *ctx,
+	t_base64_ctx *c,
 	t_byte1 blk[FT_BASE64_DECODE_BLOCK_SIZE],
 	t_byte1 decoded_block[FT_BASE64_ENCODE_BLOCK_SIZE]
 )
@@ -12,14 +29,11 @@ void	ft_base64_decode_transform
 	t_byte1		second_index;
 	t_byte1		third_index;
 	t_byte1		fourth_index;
-	const char	*alphabet;
-
-	alphabet = (const char *)ctx->alphabet;
-	first_index = ft_strchr(alphabet, blk[0]) - alphabet;
-	second_index = ft_strchr(alphabet, blk[1]) - alphabet;
-	third_index = blk[2] == '=' ? 0 : ft_strchr(alphabet, blk[2]) - alphabet;
-	fourth_index = blk[3] == '=' ? 0 : ft_strchr(alphabet, blk[3]) - alphabet;
 
+	first_index = get_alphabet_index(c->alphabet, blk[0]);
+	second_index = get_alphabet_index(c->alphabet, blk[1]);
+	third_index = blk[2] == '=' ? 0 : get_alphabet_index(c->alphabet, blk[2]);
+	fourth_index = blk[3] == '=' ? 0 : get_alphabet_index(c->alphabet, blk[3]);
 	decoded_block[0] = first_index << 2 | second_index >> 4;
 	decoded_block[1] = second_index << 4 | third_index >> 2;
 	decoded_block[2] = third_index << 6 | fourth_index;

t/cases/TWE=.decode.txt

@@ -0,0 +1 @@
+TWE=

t/cases/TWFu.decode.txt

@@ -0,0 +1 @@
+TWFu

t/cases/TWFu_whitespaces.decode.txt

@@ -0,0 +1,4 @@
+T
+W   F
+u
+

t/cases/invalid.decode.txt

@@ -0,0 +1 @@
+$TWFu