Commit afbbdb2c67
Changed files (4)
doc/langref.html.in
@@ -5414,8 +5414,9 @@ export fn decode_base_64(dest_ptr: &u8, dest_len: usize,
{
const src = source_ptr[0..source_len];
const dest = dest_ptr[0..dest_len];
- const decoded_size = base64.calcDecodedSizeExactUnsafe(src, base64.standard_pad_char);
- base64.decodeExactUnsafe(dest[0..decoded_size], src, base64.standard_alphabet_unsafe);
+ const base64_decoder = base64.standard_decoder_unsafe;
+ const decoded_size = base64_decoder.calcSize(src);
+ base64_decoder.decode(dest[0..decoded_size], src);
return decoded_size;
}
</code></pre>
example/mix_o_files/base64.zig
@@ -3,7 +3,8 @@ const base64 = @import("std").base64;
export fn decode_base_64(dest_ptr: &u8, dest_len: usize, source_ptr: &const u8, source_len: usize) -> usize {
const src = source_ptr[0..source_len];
const dest = dest_ptr[0..dest_len];
- const decoded_size = base64.calcDecodedSizeExactUnsafe(src, base64.standard_pad_char);
- base64.decodeExactUnsafe(dest[0..decoded_size], src, base64.standard_alphabet_unsafe);
+ const base64_decoder = base64.standard_decoder_unsafe;
+ const decoded_size = base64_decoder.calcSize(src);
+ base64_decoder.decode(dest[0..decoded_size], src);
return decoded_size;
}
std/os/index.zig
@@ -622,7 +622,9 @@ pub fn symLinkPosix(allocator: &Allocator, existing_path: []const u8, new_path:
}
// here we replace the standard +/ with -_ so that it can be used in a file name
-const b64_fs_alphabet_chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_";
+const b64_fs_encoder = base64.Base64Encoder.init(
+ "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_",
+ base64.standard_pad_char);
pub fn atomicSymLink(allocator: &Allocator, existing_path: []const u8, new_path: []const u8) -> %void {
if (symLink(allocator, existing_path, new_path)) {
@@ -634,12 +636,12 @@ pub fn atomicSymLink(allocator: &Allocator, existing_path: []const u8, new_path:
}
var rand_buf: [12]u8 = undefined;
- const tmp_path = %return allocator.alloc(u8, new_path.len + base64.calcEncodedSize(rand_buf.len));
+ const tmp_path = %return allocator.alloc(u8, new_path.len + base64.Base64Encoder.calcSize(rand_buf.len));
defer allocator.free(tmp_path);
mem.copy(u8, tmp_path[0..], new_path);
while (true) {
%return getRandomBytes(rand_buf[0..]);
- base64.encode(tmp_path[new_path.len..], rand_buf, b64_fs_alphabet_chars, base64.standard_pad_char);
+ b64_fs_encoder.encode(tmp_path[new_path.len..], rand_buf);
if (symLink(allocator, existing_path, tmp_path)) {
return rename(allocator, tmp_path, new_path);
} else |err| {
@@ -717,11 +719,11 @@ pub fn copyFile(allocator: &Allocator, source_path: []const u8, dest_path: []con
/// Guaranteed to be atomic.
pub fn copyFileMode(allocator: &Allocator, source_path: []const u8, dest_path: []const u8, mode: usize) -> %void {
var rand_buf: [12]u8 = undefined;
- const tmp_path = %return allocator.alloc(u8, dest_path.len + base64.calcEncodedSize(rand_buf.len));
+ const tmp_path = %return allocator.alloc(u8, dest_path.len + base64.Base64Encoder.calcSize(rand_buf.len));
defer allocator.free(tmp_path);
mem.copy(u8, tmp_path[0..], dest_path);
%return getRandomBytes(rand_buf[0..]);
- base64.encode(tmp_path[dest_path.len..], rand_buf, b64_fs_alphabet_chars, base64.standard_pad_char);
+ b64_fs_encoder.encode(tmp_path[dest_path.len..], rand_buf);
var out_file = %return io.File.openWriteMode(tmp_path, mode, allocator);
defer out_file.close();
std/base64.zig
@@ -3,64 +3,85 @@ const mem = @import("mem.zig");
pub const standard_alphabet_chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
pub const standard_pad_char = '=';
+pub const standard_encoder = Base64Encoder.init(standard_alphabet_chars, standard_pad_char);
-/// ceil(source_len * 4/3)
-pub fn calcEncodedSize(source_len: usize) -> usize {
- return @divTrunc(source_len + 2, 3) * 4;
-}
-
-/// dest.len must be what you get from ::calcEncodedSize.
-/// It is assumed that alphabet_chars and pad_char are all unique characters.
-pub fn encode(dest: []u8, source: []const u8, alphabet_chars: []const u8, pad_char: u8) {
- assert(alphabet_chars.len == 64);
- assert(dest.len == calcEncodedSize(source.len));
-
- var i: usize = 0;
- var out_index: usize = 0;
- while (i + 2 < source.len) : (i += 3) {
- dest[out_index] = alphabet_chars[(source[i] >> 2) & 0x3f];
- out_index += 1;
+pub const Base64Encoder = struct {
+ alphabet_chars: []const u8,
+ pad_char: u8,
- dest[out_index] = alphabet_chars[((source[i] & 0x3) << 4) |
- ((source[i + 1] & 0xf0) >> 4)];
- out_index += 1;
+ /// a bunch of assertions, then simply pass the data right through.
+ pub fn init(alphabet_chars: []const u8, pad_char: u8) -> Base64Encoder {
+ assert(alphabet_chars.len == 64);
+ var char_in_alphabet = []bool{false} ** 256;
+ for (alphabet_chars) |c| {
+ assert(!char_in_alphabet[c]);
+ assert(c != pad_char);
+ char_in_alphabet[c] = true;
+ }
- dest[out_index] = alphabet_chars[((source[i + 1] & 0xf) << 2) |
- ((source[i + 2] & 0xc0) >> 6)];
- out_index += 1;
+ return Base64Encoder{
+ .alphabet_chars = alphabet_chars,
+ .pad_char = pad_char,
+ };
+ }
- dest[out_index] = alphabet_chars[source[i + 2] & 0x3f];
- out_index += 1;
+ /// ceil(source_len * 4/3)
+ pub fn calcSize(source_len: usize) -> usize {
+ return @divTrunc(source_len + 2, 3) * 4;
}
- if (i < source.len) {
- dest[out_index] = alphabet_chars[(source[i] >> 2) & 0x3f];
- out_index += 1;
+ /// dest.len must be what you get from ::calcSize.
+ pub fn encode(encoder: &const Base64Encoder, dest: []u8, source: []const u8) {
+ assert(dest.len == Base64Encoder.calcSize(source.len));
- if (i + 1 == source.len) {
- dest[out_index] = alphabet_chars[(source[i] & 0x3) << 4];
+ var i: usize = 0;
+ var out_index: usize = 0;
+ while (i + 2 < source.len) : (i += 3) {
+ dest[out_index] = encoder.alphabet_chars[(source[i] >> 2) & 0x3f];
out_index += 1;
- dest[out_index] = pad_char;
- out_index += 1;
- } else {
- dest[out_index] = alphabet_chars[((source[i] & 0x3) << 4) |
+ dest[out_index] = encoder.alphabet_chars[((source[i] & 0x3) << 4) |
((source[i + 1] & 0xf0) >> 4)];
out_index += 1;
- dest[out_index] = alphabet_chars[(source[i + 1] & 0xf) << 2];
+ dest[out_index] = encoder.alphabet_chars[((source[i + 1] & 0xf) << 2) |
+ ((source[i + 2] & 0xc0) >> 6)];
+ out_index += 1;
+
+ dest[out_index] = encoder.alphabet_chars[source[i + 2] & 0x3f];
out_index += 1;
}
- dest[out_index] = pad_char;
- out_index += 1;
+ if (i < source.len) {
+ dest[out_index] = encoder.alphabet_chars[(source[i] >> 2) & 0x3f];
+ out_index += 1;
+
+ if (i + 1 == source.len) {
+ dest[out_index] = encoder.alphabet_chars[(source[i] & 0x3) << 4];
+ out_index += 1;
+
+ dest[out_index] = encoder.pad_char;
+ out_index += 1;
+ } else {
+ dest[out_index] = encoder.alphabet_chars[((source[i] & 0x3) << 4) |
+ ((source[i + 1] & 0xf0) >> 4)];
+ out_index += 1;
+
+ dest[out_index] = encoder.alphabet_chars[(source[i + 1] & 0xf) << 2];
+ out_index += 1;
+ }
+
+ dest[out_index] = encoder.pad_char;
+ out_index += 1;
+ }
}
-}
+};
-pub const standard_alphabet = Base64Alphabet.init(standard_alphabet_chars, standard_pad_char);
+pub const standard_decoder = Base64Decoder.init(standard_alphabet_chars, standard_pad_char);
+error InvalidPadding;
+error InvalidCharacter;
-/// For use with ::decodeExact.
-pub const Base64Alphabet = struct {
+pub const Base64Decoder = struct {
/// e.g. 'A' => 0.
/// undefined for any value not in the 64 alphabet chars.
char_to_index: [256]u8,
@@ -68,10 +89,10 @@ pub const Base64Alphabet = struct {
char_in_alphabet: [256]bool,
pad_char: u8,
- pub fn init(alphabet_chars: []const u8, pad_char: u8) -> Base64Alphabet {
+ pub fn init(alphabet_chars: []const u8, pad_char: u8) -> Base64Decoder {
assert(alphabet_chars.len == 64);
- var result = Base64Alphabet{
+ var result = Base64Decoder{
.char_to_index = undefined,
.char_in_alphabet = []bool{false} ** 256,
.pad_char = pad_char,
@@ -87,197 +108,193 @@ pub const Base64Alphabet = struct {
return result;
}
-};
-error InvalidPadding;
-/// For use with ::decodeExact.
-/// If the encoded buffer is detected to be invalid, returns error.InvalidPadding.
-pub fn calcDecodedSizeExact(encoded: []const u8, pad_char: u8) -> %usize {
- if (encoded.len % 4 != 0) return error.InvalidPadding;
- return calcDecodedSizeExactUnsafe(encoded, pad_char);
-}
+ /// If the encoded buffer is detected to be invalid, returns error.InvalidPadding.
+ pub fn calcSize(decoder: &const Base64Decoder, source: []const u8) -> %usize {
+ if (source.len % 4 != 0) return error.InvalidPadding;
+ return calcDecodedSizeExactUnsafe(source, decoder.pad_char);
+ }
-error InvalidCharacter;
-/// dest.len must be what you get from ::calcDecodedSizeExact.
-/// invalid characters result in error.InvalidCharacter.
-/// invalid padding results in error.InvalidPadding.
-pub fn decodeExact(dest: []u8, source: []const u8, alphabet: &const Base64Alphabet) -> %void {
- assert(dest.len == %%calcDecodedSizeExact(source, alphabet.pad_char));
- assert(source.len % 4 == 0);
-
- var src_cursor: usize = 0;
- var dest_cursor: usize = 0;
-
- while (src_cursor < source.len) : (src_cursor += 4) {
- if (!alphabet.char_in_alphabet[source[src_cursor + 0]]) return error.InvalidCharacter;
- if (!alphabet.char_in_alphabet[source[src_cursor + 1]]) return error.InvalidCharacter;
- if (src_cursor < source.len - 4 or source[src_cursor + 3] != alphabet.pad_char) {
- // common case
- if (!alphabet.char_in_alphabet[source[src_cursor + 2]]) return error.InvalidCharacter;
- if (!alphabet.char_in_alphabet[source[src_cursor + 3]]) return error.InvalidCharacter;
- dest[dest_cursor + 0] = alphabet.char_to_index[source[src_cursor + 0]] << 2 |
- alphabet.char_to_index[source[src_cursor + 1]] >> 4;
- dest[dest_cursor + 1] = alphabet.char_to_index[source[src_cursor + 1]] << 4 |
- alphabet.char_to_index[source[src_cursor + 2]] >> 2;
- dest[dest_cursor + 2] = alphabet.char_to_index[source[src_cursor + 2]] << 6 |
- alphabet.char_to_index[source[src_cursor + 3]];
- dest_cursor += 3;
- } else if (source[src_cursor + 2] != alphabet.pad_char) {
- // one pad char
- if (!alphabet.char_in_alphabet[source[src_cursor + 2]]) return error.InvalidCharacter;
- dest[dest_cursor + 0] = alphabet.char_to_index[source[src_cursor + 0]] << 2 |
- alphabet.char_to_index[source[src_cursor + 1]] >> 4;
- dest[dest_cursor + 1] = alphabet.char_to_index[source[src_cursor + 1]] << 4 |
- alphabet.char_to_index[source[src_cursor + 2]] >> 2;
- if (alphabet.char_to_index[source[src_cursor + 2]] << 6 != 0) return error.InvalidPadding;
- dest_cursor += 2;
- } else {
- // two pad chars
- dest[dest_cursor + 0] = alphabet.char_to_index[source[src_cursor + 0]] << 2 |
- alphabet.char_to_index[source[src_cursor + 1]] >> 4;
- if (alphabet.char_to_index[source[src_cursor + 1]] << 4 != 0) return error.InvalidPadding;
- dest_cursor += 1;
+ /// dest.len must be what you get from ::calcSize.
+ /// invalid characters result in error.InvalidCharacter.
+ /// invalid padding results in error.InvalidPadding.
+ pub fn decode(decoder: &const Base64Decoder, dest: []u8, source: []const u8) -> %void {
+ assert(dest.len == %%decoder.calcSize(source));
+ assert(source.len % 4 == 0);
+
+ var src_cursor: usize = 0;
+ var dest_cursor: usize = 0;
+
+ while (src_cursor < source.len) : (src_cursor += 4) {
+ if (!decoder.char_in_alphabet[source[src_cursor + 0]]) return error.InvalidCharacter;
+ if (!decoder.char_in_alphabet[source[src_cursor + 1]]) return error.InvalidCharacter;
+ if (src_cursor < source.len - 4 or source[src_cursor + 3] != decoder.pad_char) {
+ // common case
+ if (!decoder.char_in_alphabet[source[src_cursor + 2]]) return error.InvalidCharacter;
+ if (!decoder.char_in_alphabet[source[src_cursor + 3]]) return error.InvalidCharacter;
+ dest[dest_cursor + 0] = decoder.char_to_index[source[src_cursor + 0]] << 2 |
+ decoder.char_to_index[source[src_cursor + 1]] >> 4;
+ dest[dest_cursor + 1] = decoder.char_to_index[source[src_cursor + 1]] << 4 |
+ decoder.char_to_index[source[src_cursor + 2]] >> 2;
+ dest[dest_cursor + 2] = decoder.char_to_index[source[src_cursor + 2]] << 6 |
+ decoder.char_to_index[source[src_cursor + 3]];
+ dest_cursor += 3;
+ } else if (source[src_cursor + 2] != decoder.pad_char) {
+ // one pad char
+ if (!decoder.char_in_alphabet[source[src_cursor + 2]]) return error.InvalidCharacter;
+ dest[dest_cursor + 0] = decoder.char_to_index[source[src_cursor + 0]] << 2 |
+ decoder.char_to_index[source[src_cursor + 1]] >> 4;
+ dest[dest_cursor + 1] = decoder.char_to_index[source[src_cursor + 1]] << 4 |
+ decoder.char_to_index[source[src_cursor + 2]] >> 2;
+ if (decoder.char_to_index[source[src_cursor + 2]] << 6 != 0) return error.InvalidPadding;
+ dest_cursor += 2;
+ } else {
+ // two pad chars
+ dest[dest_cursor + 0] = decoder.char_to_index[source[src_cursor + 0]] << 2 |
+ decoder.char_to_index[source[src_cursor + 1]] >> 4;
+ if (decoder.char_to_index[source[src_cursor + 1]] << 4 != 0) return error.InvalidPadding;
+ dest_cursor += 1;
+ }
}
+
+ assert(src_cursor == source.len);
+ assert(dest_cursor == dest.len);
}
+};
- assert(src_cursor == source.len);
- assert(dest_cursor == dest.len);
-}
+error OutputTooSmall;
-/// For use with ::decodeWithIgnore.
-pub const Base64AlphabetWithIgnore = struct {
- alphabet: Base64Alphabet,
+pub const Base64DecoderWithIgnore = struct {
+ decoder: Base64Decoder,
char_is_ignored: [256]bool,
- pub fn init(alphabet_chars: []const u8, pad_char: u8, ignore_chars: []const u8) -> Base64AlphabetWithIgnore {
- var result = Base64AlphabetWithIgnore {
- .alphabet = Base64Alphabet.init(alphabet_chars, pad_char),
+ pub fn init(alphabet_chars: []const u8, pad_char: u8, ignore_chars: []const u8) -> Base64DecoderWithIgnore {
+ var result = Base64DecoderWithIgnore {
+ .decoder = Base64Decoder.init(alphabet_chars, pad_char),
.char_is_ignored = []bool{false} ** 256,
};
for (ignore_chars) |c| {
- assert(!result.alphabet.char_in_alphabet[c]);
+ assert(!result.decoder.char_in_alphabet[c]);
assert(!result.char_is_ignored[c]);
- assert(result.alphabet.pad_char != c);
+ assert(result.decoder.pad_char != c);
result.char_is_ignored[c] = true;
}
return result;
}
-};
-/// For use with ::decodeWithIgnore.
-/// If no characters end up being ignored, this will be the exact decoded size.
-pub fn calcDecodedSizeUpperBound(encoded_len: usize) -> %usize {
- return @divTrunc(encoded_len, 4) * 3;
-}
+ /// If no characters end up being ignored or padding, this will be the exact decoded size.
+ pub fn calcSizeUpperBound(encoded_len: usize) -> %usize {
+ return @divTrunc(encoded_len, 4) * 3;
+ }
-error OutputTooSmall;
-/// Invalid characters that are not ignored results in error.InvalidCharacter.
-/// Invalid padding results in error.InvalidPadding.
-/// Decoding more data than can fit in dest results in error.OutputTooSmall. See also ::calcDecodedSizeUpperBound.
-/// Returns the number of bytes writen to dest.
-pub fn decodeWithIgnore(dest: []u8, source: []const u8, alphabet_with_ignore: &const Base64AlphabetWithIgnore) -> %usize {
- const alphabet = &const alphabet_with_ignore.alphabet;
-
- var src_cursor: usize = 0;
- var dest_cursor: usize = 0;
-
- while (true) {
- // get the next 4 chars, if available
- var next_4_chars: [4]u8 = undefined;
- var available_chars: usize = 0;
- var pad_char_count: usize = 0;
- while (available_chars < 4 and src_cursor < source.len) {
- var c = source[src_cursor];
- src_cursor += 1;
-
- if (alphabet.char_in_alphabet[c]) {
- // normal char
- next_4_chars[available_chars] = c;
- available_chars += 1;
- } else if (alphabet_with_ignore.char_is_ignored[c]) {
- // we're told to skip this one
- continue;
- } else if (c == alphabet.pad_char) {
- // the padding has begun. count the pad chars.
- pad_char_count += 1;
- while (src_cursor < source.len) {
- c = source[src_cursor];
- src_cursor += 1;
- if (c == alphabet.pad_char) {
- pad_char_count += 1;
- if (pad_char_count > 2) return error.InvalidCharacter;
- } else if (alphabet_with_ignore.char_is_ignored[c]) {
- // we can even ignore chars during the padding
- continue;
- } else return error.InvalidCharacter;
- }
- break;
- } else return error.InvalidCharacter;
+ /// Invalid characters that are not ignored result in error.InvalidCharacter.
+ /// Invalid padding results in error.InvalidPadding.
+ /// Decoding more data than can fit in dest results in error.OutputTooSmall. See also ::calcSizeUpperBound.
+ /// Returns the number of bytes writen to dest.
+ pub fn decode(decoder_with_ignore: &const Base64DecoderWithIgnore, dest: []u8, source: []const u8) -> %usize {
+ const decoder = &const decoder_with_ignore.decoder;
+
+ var src_cursor: usize = 0;
+ var dest_cursor: usize = 0;
+
+ while (true) {
+ // get the next 4 chars, if available
+ var next_4_chars: [4]u8 = undefined;
+ var available_chars: usize = 0;
+ var pad_char_count: usize = 0;
+ while (available_chars < 4 and src_cursor < source.len) {
+ var c = source[src_cursor];
+ src_cursor += 1;
+
+ if (decoder.char_in_alphabet[c]) {
+ // normal char
+ next_4_chars[available_chars] = c;
+ available_chars += 1;
+ } else if (decoder_with_ignore.char_is_ignored[c]) {
+ // we're told to skip this one
+ continue;
+ } else if (c == decoder.pad_char) {
+ // the padding has begun. count the pad chars.
+ pad_char_count += 1;
+ while (src_cursor < source.len) {
+ c = source[src_cursor];
+ src_cursor += 1;
+ if (c == decoder.pad_char) {
+ pad_char_count += 1;
+ if (pad_char_count > 2) return error.InvalidCharacter;
+ } else if (decoder_with_ignore.char_is_ignored[c]) {
+ // we can even ignore chars during the padding
+ continue;
+ } else return error.InvalidCharacter;
+ }
+ break;
+ } else return error.InvalidCharacter;
+ }
+
+ switch (available_chars) {
+ 4 => {
+ // common case
+ if (dest_cursor + 3 > dest.len) return error.OutputTooSmall;
+ assert(pad_char_count == 0);
+ dest[dest_cursor + 0] = decoder.char_to_index[next_4_chars[0]] << 2 |
+ decoder.char_to_index[next_4_chars[1]] >> 4;
+ dest[dest_cursor + 1] = decoder.char_to_index[next_4_chars[1]] << 4 |
+ decoder.char_to_index[next_4_chars[2]] >> 2;
+ dest[dest_cursor + 2] = decoder.char_to_index[next_4_chars[2]] << 6 |
+ decoder.char_to_index[next_4_chars[3]];
+ dest_cursor += 3;
+ continue;
+ },
+ 3 => {
+ if (dest_cursor + 2 > dest.len) return error.OutputTooSmall;
+ if (pad_char_count != 1) return error.InvalidPadding;
+ dest[dest_cursor + 0] = decoder.char_to_index[next_4_chars[0]] << 2 |
+ decoder.char_to_index[next_4_chars[1]] >> 4;
+ dest[dest_cursor + 1] = decoder.char_to_index[next_4_chars[1]] << 4 |
+ decoder.char_to_index[next_4_chars[2]] >> 2;
+ if (decoder.char_to_index[next_4_chars[2]] << 6 != 0) return error.InvalidPadding;
+ dest_cursor += 2;
+ break;
+ },
+ 2 => {
+ if (dest_cursor + 1 > dest.len) return error.OutputTooSmall;
+ if (pad_char_count != 2) return error.InvalidPadding;
+ dest[dest_cursor + 0] = decoder.char_to_index[next_4_chars[0]] << 2 |
+ decoder.char_to_index[next_4_chars[1]] >> 4;
+ if (decoder.char_to_index[next_4_chars[1]] << 4 != 0) return error.InvalidPadding;
+ dest_cursor += 1;
+ break;
+ },
+ 1 => {
+ return error.InvalidPadding;
+ },
+ 0 => {
+ if (pad_char_count != 0) return error.InvalidPadding;
+ break;
+ },
+ else => unreachable,
+ }
}
- switch (available_chars) {
- 4 => {
- // common case
- if (dest_cursor + 3 > dest.len) return error.OutputTooSmall;
- assert(pad_char_count == 0);
- dest[dest_cursor + 0] = alphabet.char_to_index[next_4_chars[0]] << 2 |
- alphabet.char_to_index[next_4_chars[1]] >> 4;
- dest[dest_cursor + 1] = alphabet.char_to_index[next_4_chars[1]] << 4 |
- alphabet.char_to_index[next_4_chars[2]] >> 2;
- dest[dest_cursor + 2] = alphabet.char_to_index[next_4_chars[2]] << 6 |
- alphabet.char_to_index[next_4_chars[3]];
- dest_cursor += 3;
- continue;
- },
- 3 => {
- if (dest_cursor + 2 > dest.len) return error.OutputTooSmall;
- if (pad_char_count != 1) return error.InvalidPadding;
- dest[dest_cursor + 0] = alphabet.char_to_index[next_4_chars[0]] << 2 |
- alphabet.char_to_index[next_4_chars[1]] >> 4;
- dest[dest_cursor + 1] = alphabet.char_to_index[next_4_chars[1]] << 4 |
- alphabet.char_to_index[next_4_chars[2]] >> 2;
- if (alphabet.char_to_index[next_4_chars[2]] << 6 != 0) return error.InvalidPadding;
- dest_cursor += 2;
- break;
- },
- 2 => {
- if (dest_cursor + 1 > dest.len) return error.OutputTooSmall;
- if (pad_char_count != 2) return error.InvalidPadding;
- dest[dest_cursor + 0] = alphabet.char_to_index[next_4_chars[0]] << 2 |
- alphabet.char_to_index[next_4_chars[1]] >> 4;
- if (alphabet.char_to_index[next_4_chars[1]] << 4 != 0) return error.InvalidPadding;
- dest_cursor += 1;
- break;
- },
- 1 => {
- return error.InvalidPadding;
- },
- 0 => {
- if (pad_char_count != 0) return error.InvalidPadding;
- break;
- },
- else => unreachable,
- }
+ assert(src_cursor == source.len);
+
+ return dest_cursor;
}
+};
- assert(src_cursor == source.len);
- return dest_cursor;
-}
+pub const standard_decoder_unsafe = Base64DecoderUnsafe.init(standard_alphabet_chars, standard_pad_char);
-pub const standard_alphabet_unsafe = Base64AlphabetUnsafe.init(standard_alphabet_chars, standard_pad_char);
-
-/// For use with ::decodeExactUnsafe.
-pub const Base64AlphabetUnsafe = struct {
+pub const Base64DecoderUnsafe = struct {
/// e.g. 'A' => 0.
/// undefined for any value not in the 64 alphabet chars.
char_to_index: [256]u8,
pad_char: u8,
- pub fn init(alphabet_chars: []const u8, pad_char: u8) -> Base64AlphabetUnsafe {
+ pub fn init(alphabet_chars: []const u8, pad_char: u8) -> Base64DecoderUnsafe {
assert(alphabet_chars.len == 64);
- var result = Base64AlphabetUnsafe {
+ var result = Base64DecoderUnsafe {
.char_to_index = undefined,
.pad_char = pad_char,
};
@@ -287,69 +304,73 @@ pub const Base64AlphabetUnsafe = struct {
}
return result;
}
-};
-/// For use with ::decodeExactUnsafe.
-/// The encoded buffer must be valid.
-pub fn calcDecodedSizeExactUnsafe(encoded: []const u8, pad_char: u8) -> usize {
- if (encoded.len == 0) return 0;
- var result = @divExact(encoded.len, 4) * 3;
- if (encoded[encoded.len - 1] == pad_char) {
- result -= 1;
- if (encoded[encoded.len - 2] == pad_char) {
- result -= 1;
- }
+ /// The source buffer must be valid.
+ pub fn calcSize(decoder: &const Base64DecoderUnsafe, source: []const u8) -> usize {
+ return calcDecodedSizeExactUnsafe(source, decoder.pad_char);
}
- return result;
-}
-/// dest.len must be what you get from ::calcDecodedSizeExactUnsafe.
-/// invalid characters or padding will result in undefined values.
-pub fn decodeExactUnsafe(dest: []u8, source: []const u8, alphabet: &const Base64AlphabetUnsafe) {
- assert(dest.len == calcDecodedSizeExactUnsafe(source, alphabet.pad_char));
+ /// dest.len must be what you get from ::calcDecodedSizeExactUnsafe.
+ /// invalid characters or padding will result in undefined values.
+ pub fn decode(decoder: &const Base64DecoderUnsafe, dest: []u8, source: []const u8) {
+ assert(dest.len == decoder.calcSize(source));
- var src_index: usize = 0;
- var dest_index: usize = 0;
- var in_buf_len: usize = source.len;
+ var src_index: usize = 0;
+ var dest_index: usize = 0;
+ var in_buf_len: usize = source.len;
- while (in_buf_len > 0 and source[in_buf_len - 1] == alphabet.pad_char) {
- in_buf_len -= 1;
- }
+ while (in_buf_len > 0 and source[in_buf_len - 1] == decoder.pad_char) {
+ in_buf_len -= 1;
+ }
- while (in_buf_len > 4) {
- dest[dest_index] = alphabet.char_to_index[source[src_index + 0]] << 2 |
- alphabet.char_to_index[source[src_index + 1]] >> 4;
- dest_index += 1;
+ while (in_buf_len > 4) {
+ dest[dest_index] = decoder.char_to_index[source[src_index + 0]] << 2 |
+ decoder.char_to_index[source[src_index + 1]] >> 4;
+ dest_index += 1;
- dest[dest_index] = alphabet.char_to_index[source[src_index + 1]] << 4 |
- alphabet.char_to_index[source[src_index + 2]] >> 2;
- dest_index += 1;
+ dest[dest_index] = decoder.char_to_index[source[src_index + 1]] << 4 |
+ decoder.char_to_index[source[src_index + 2]] >> 2;
+ dest_index += 1;
- dest[dest_index] = alphabet.char_to_index[source[src_index + 2]] << 6 |
- alphabet.char_to_index[source[src_index + 3]];
- dest_index += 1;
+ dest[dest_index] = decoder.char_to_index[source[src_index + 2]] << 6 |
+ decoder.char_to_index[source[src_index + 3]];
+ dest_index += 1;
- src_index += 4;
- in_buf_len -= 4;
- }
+ src_index += 4;
+ in_buf_len -= 4;
+ }
- if (in_buf_len > 1) {
- dest[dest_index] = alphabet.char_to_index[source[src_index + 0]] << 2 |
- alphabet.char_to_index[source[src_index + 1]] >> 4;
- dest_index += 1;
- }
- if (in_buf_len > 2) {
- dest[dest_index] = alphabet.char_to_index[source[src_index + 1]] << 4 |
- alphabet.char_to_index[source[src_index + 2]] >> 2;
- dest_index += 1;
+ if (in_buf_len > 1) {
+ dest[dest_index] = decoder.char_to_index[source[src_index + 0]] << 2 |
+ decoder.char_to_index[source[src_index + 1]] >> 4;
+ dest_index += 1;
+ }
+ if (in_buf_len > 2) {
+ dest[dest_index] = decoder.char_to_index[source[src_index + 1]] << 4 |
+ decoder.char_to_index[source[src_index + 2]] >> 2;
+ dest_index += 1;
+ }
+ if (in_buf_len > 3) {
+ dest[dest_index] = decoder.char_to_index[source[src_index + 2]] << 6 |
+ decoder.char_to_index[source[src_index + 3]];
+ dest_index += 1;
+ }
}
- if (in_buf_len > 3) {
- dest[dest_index] = alphabet.char_to_index[source[src_index + 2]] << 6 |
- alphabet.char_to_index[source[src_index + 3]];
- dest_index += 1;
+};
+
+fn calcDecodedSizeExactUnsafe(source: []const u8, pad_char: u8) -> usize {
+ if (source.len == 0) return 0;
+ var result = @divExact(source.len, 4) * 3;
+ if (source[source.len - 1] == pad_char) {
+ result -= 1;
+ if (source[source.len - 2] == pad_char) {
+ result -= 1;
+ }
}
+ return result;
}
+
test "base64" {
@setEvalBranchQuota(5000);
%%testBase64();
@@ -391,74 +412,74 @@ fn testBase64() -> %void {
}
fn testAllApis(expected_decoded: []const u8, expected_encoded: []const u8) -> %void {
- // encode
+ // Base64Encoder
{
var buffer: [0x100]u8 = undefined;
- var encoded = buffer[0..calcEncodedSize(expected_decoded.len)];
- encode(encoded, expected_decoded, standard_alphabet_chars, standard_pad_char);
+ var encoded = buffer[0..Base64Encoder.calcSize(expected_decoded.len)];
+ standard_encoder.encode(encoded, expected_decoded);
assert(mem.eql(u8, encoded, expected_encoded));
}
- // decodeExact
+ // Base64Decoder
{
var buffer: [0x100]u8 = undefined;
- var decoded = buffer[0..%return calcDecodedSizeExact(expected_encoded, standard_pad_char)];
- %return decodeExact(decoded, expected_encoded, standard_alphabet);
+ var decoded = buffer[0..%return standard_decoder.calcSize(expected_encoded)];
+ %return standard_decoder.decode(decoded, expected_encoded);
assert(mem.eql(u8, decoded, expected_decoded));
}
- // decodeWithIgnore
+ // Base64DecoderWithIgnore
{
- const standard_alphabet_ignore_nothing = Base64AlphabetWithIgnore.init(
+ const standard_decoder_ignore_nothing = Base64DecoderWithIgnore.init(
standard_alphabet_chars, standard_pad_char, "");
var buffer: [0x100]u8 = undefined;
- var decoded = buffer[0..%return calcDecodedSizeUpperBound(expected_encoded.len)];
- var written = %return decodeWithIgnore(decoded, expected_encoded, standard_alphabet_ignore_nothing);
+ var decoded = buffer[0..%return Base64DecoderWithIgnore.calcSizeUpperBound(expected_encoded.len)];
+ var written = %return standard_decoder_ignore_nothing.decode(decoded, expected_encoded);
assert(written <= decoded.len);
assert(mem.eql(u8, decoded[0..written], expected_decoded));
}
- // decodeExactUnsafe
+ // Base64DecoderUnsafe
{
var buffer: [0x100]u8 = undefined;
- var decoded = buffer[0..calcDecodedSizeExactUnsafe(expected_encoded, standard_pad_char)];
- decodeExactUnsafe(decoded, expected_encoded, standard_alphabet_unsafe);
+ var decoded = buffer[0..standard_decoder_unsafe.calcSize(expected_encoded)];
+ standard_decoder_unsafe.decode(decoded, expected_encoded);
assert(mem.eql(u8, decoded, expected_decoded));
}
}
fn testDecodeIgnoreSpace(expected_decoded: []const u8, encoded: []const u8) -> %void {
- const standard_alphabet_ignore_space = Base64AlphabetWithIgnore.init(
+ const standard_decoder_ignore_space = Base64DecoderWithIgnore.init(
standard_alphabet_chars, standard_pad_char, " ");
var buffer: [0x100]u8 = undefined;
- var decoded = buffer[0..%return calcDecodedSizeUpperBound(encoded.len)];
- var written = %return decodeWithIgnore(decoded, encoded, standard_alphabet_ignore_space);
+ var decoded = buffer[0..%return Base64DecoderWithIgnore.calcSizeUpperBound(encoded.len)];
+ var written = %return standard_decoder_ignore_space.decode(decoded, encoded);
assert(mem.eql(u8, decoded[0..written], expected_decoded));
}
error ExpectedError;
fn testError(encoded: []const u8, expected_err: error) -> %void {
- const standard_alphabet_ignore_space = Base64AlphabetWithIgnore.init(
+ const standard_decoder_ignore_space = Base64DecoderWithIgnore.init(
standard_alphabet_chars, standard_pad_char, " ");
var buffer: [0x100]u8 = undefined;
- if (calcDecodedSizeExact(encoded, standard_pad_char)) |decoded_size| {
+ if (standard_decoder.calcSize(encoded)) |decoded_size| {
var decoded = buffer[0..decoded_size];
- if (decodeExact(decoded, encoded, standard_alphabet)) |_| {
+ if (standard_decoder.decode(decoded, encoded)) |_| {
return error.ExpectedError;
} else |err| if (err != expected_err) return err;
} else |err| if (err != expected_err) return err;
- if (decodeWithIgnore(buffer[0..], encoded, standard_alphabet_ignore_space)) |_| {
+ if (standard_decoder_ignore_space.decode(buffer[0..], encoded)) |_| {
return error.ExpectedError;
} else |err| if (err != expected_err) return err;
}
fn testOutputTooSmallError(encoded: []const u8) -> %void {
- const standard_alphabet_ignore_space = Base64AlphabetWithIgnore.init(
+ const standard_decoder_ignore_space = Base64DecoderWithIgnore.init(
standard_alphabet_chars, standard_pad_char, " ");
var buffer: [0x100]u8 = undefined;
var decoded = buffer[0..calcDecodedSizeExactUnsafe(encoded, standard_pad_char) - 1];
- if (decodeWithIgnore(decoded, encoded, standard_alphabet_ignore_space)) |_| {
+ if (standard_decoder_ignore_space.decode(decoded, encoded)) |_| {
return error.ExpectedError;
} else |err| if (err != error.OutputTooSmall) return err;
}