master
1//! Base64 encoding/decoding as specified by
2//! [RFC 4648](https://datatracker.ietf.org/doc/html/rfc4648).
3
4const std = @import("std.zig");
5const assert = std.debug.assert;
6const builtin = @import("builtin");
7const testing = std.testing;
8const mem = std.mem;
9const window = mem.window;
10
11pub const Error = error{
12 InvalidCharacter,
13 InvalidPadding,
14 NoSpaceLeft,
15};
16
17const decoderWithIgnoreProto = *const fn (ignore: []const u8) Base64DecoderWithIgnore;
18
19/// Base64 codecs
20pub const Codecs = struct {
21 alphabet_chars: [64]u8,
22 pad_char: ?u8,
23 decoderWithIgnore: decoderWithIgnoreProto,
24 Encoder: Base64Encoder,
25 Decoder: Base64Decoder,
26};
27
28/// The Base64 alphabet defined in
29/// [RFC 4648 section 4](https://datatracker.ietf.org/doc/html/rfc4648#section-4).
30pub const standard_alphabet_chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/".*;
31fn standardBase64DecoderWithIgnore(ignore: []const u8) Base64DecoderWithIgnore {
32 return Base64DecoderWithIgnore.init(standard_alphabet_chars, '=', ignore);
33}
34
35/// Standard Base64 codecs, with padding, as defined in
36/// [RFC 4648 section 4](https://datatracker.ietf.org/doc/html/rfc4648#section-4).
37pub const standard = Codecs{
38 .alphabet_chars = standard_alphabet_chars,
39 .pad_char = '=',
40 .decoderWithIgnore = standardBase64DecoderWithIgnore,
41 .Encoder = Base64Encoder.init(standard_alphabet_chars, '='),
42 .Decoder = Base64Decoder.init(standard_alphabet_chars, '='),
43};
44
45/// Standard Base64 codecs, without padding, as defined in
46/// [RFC 4648 section 3.2](https://datatracker.ietf.org/doc/html/rfc4648#section-3.2).
47pub const standard_no_pad = Codecs{
48 .alphabet_chars = standard_alphabet_chars,
49 .pad_char = null,
50 .decoderWithIgnore = standardBase64DecoderWithIgnore,
51 .Encoder = Base64Encoder.init(standard_alphabet_chars, null),
52 .Decoder = Base64Decoder.init(standard_alphabet_chars, null),
53};
54
55/// The URL-safe Base64 alphabet defined in
56/// [RFC 4648 section 5](https://datatracker.ietf.org/doc/html/rfc4648#section-5).
57pub const url_safe_alphabet_chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_".*;
58fn urlSafeBase64DecoderWithIgnore(ignore: []const u8) Base64DecoderWithIgnore {
59 return Base64DecoderWithIgnore.init(url_safe_alphabet_chars, null, ignore);
60}
61
62/// URL-safe Base64 codecs, with padding, as defined in
63/// [RFC 4648 section 5](https://datatracker.ietf.org/doc/html/rfc4648#section-5).
64pub const url_safe = Codecs{
65 .alphabet_chars = url_safe_alphabet_chars,
66 .pad_char = '=',
67 .decoderWithIgnore = urlSafeBase64DecoderWithIgnore,
68 .Encoder = Base64Encoder.init(url_safe_alphabet_chars, '='),
69 .Decoder = Base64Decoder.init(url_safe_alphabet_chars, '='),
70};
71
72/// URL-safe Base64 codecs, without padding, as defined in
73/// [RFC 4648 section 3.2](https://datatracker.ietf.org/doc/html/rfc4648#section-3.2).
74pub const url_safe_no_pad = Codecs{
75 .alphabet_chars = url_safe_alphabet_chars,
76 .pad_char = null,
77 .decoderWithIgnore = urlSafeBase64DecoderWithIgnore,
78 .Encoder = Base64Encoder.init(url_safe_alphabet_chars, null),
79 .Decoder = Base64Decoder.init(url_safe_alphabet_chars, null),
80};
81
82pub const Base64Encoder = struct {
83 alphabet_chars: [64]u8,
84 pad_char: ?u8,
85
86 /// A bunch of assertions, then simply pass the data right through.
87 pub fn init(alphabet_chars: [64]u8, pad_char: ?u8) Base64Encoder {
88 assert(alphabet_chars.len == 64);
89 var char_in_alphabet = [_]bool{false} ** 256;
90 for (alphabet_chars) |c| {
91 assert(!char_in_alphabet[c]);
92 assert(pad_char == null or c != pad_char.?);
93 char_in_alphabet[c] = true;
94 }
95 return Base64Encoder{
96 .alphabet_chars = alphabet_chars,
97 .pad_char = pad_char,
98 };
99 }
100
101 /// Compute the encoded length
102 pub fn calcSize(encoder: *const Base64Encoder, source_len: usize) usize {
103 if (encoder.pad_char != null) {
104 return @divTrunc(source_len + 2, 3) * 4;
105 } else {
106 const leftover = source_len % 3;
107 return @divTrunc(source_len, 3) * 4 + @divTrunc(leftover * 4 + 2, 3);
108 }
109 }
110
111 pub fn encodeWriter(encoder: *const Base64Encoder, dest: *std.Io.Writer, source: []const u8) !void {
112 var chunker = window(u8, source, 3, 3);
113 while (chunker.next()) |chunk| {
114 var temp: [5]u8 = undefined;
115 const s = encoder.encode(&temp, chunk);
116 try dest.writeAll(s);
117 }
118 }
119
120 /// dest.len must at least be what you get from ::calcSize.
121 pub fn encode(encoder: *const Base64Encoder, dest: []u8, source: []const u8) []const u8 {
122 const out_len = encoder.calcSize(source.len);
123 assert(dest.len >= out_len);
124
125 var idx: usize = 0;
126 var out_idx: usize = 0;
127 while (idx + 15 < source.len) : (idx += 12) {
128 const bits = std.mem.readInt(u128, source[idx..][0..16], .big);
129 inline for (0..16) |i| {
130 dest[out_idx + i] = encoder.alphabet_chars[@truncate((bits >> (122 - i * 6)) & 0x3f)];
131 }
132 out_idx += 16;
133 }
134 while (idx + 3 < source.len) : (idx += 3) {
135 const bits = std.mem.readInt(u32, source[idx..][0..4], .big);
136 dest[out_idx] = encoder.alphabet_chars[(bits >> 26) & 0x3f];
137 dest[out_idx + 1] = encoder.alphabet_chars[(bits >> 20) & 0x3f];
138 dest[out_idx + 2] = encoder.alphabet_chars[(bits >> 14) & 0x3f];
139 dest[out_idx + 3] = encoder.alphabet_chars[(bits >> 8) & 0x3f];
140 out_idx += 4;
141 }
142 if (idx + 2 < source.len) {
143 dest[out_idx] = encoder.alphabet_chars[source[idx] >> 2];
144 dest[out_idx + 1] = encoder.alphabet_chars[((source[idx] & 0x3) << 4) | (source[idx + 1] >> 4)];
145 dest[out_idx + 2] = encoder.alphabet_chars[(source[idx + 1] & 0xf) << 2 | (source[idx + 2] >> 6)];
146 dest[out_idx + 3] = encoder.alphabet_chars[source[idx + 2] & 0x3f];
147 out_idx += 4;
148 } else if (idx + 1 < source.len) {
149 dest[out_idx] = encoder.alphabet_chars[source[idx] >> 2];
150 dest[out_idx + 1] = encoder.alphabet_chars[((source[idx] & 0x3) << 4) | (source[idx + 1] >> 4)];
151 dest[out_idx + 2] = encoder.alphabet_chars[(source[idx + 1] & 0xf) << 2];
152 out_idx += 3;
153 } else if (idx < source.len) {
154 dest[out_idx] = encoder.alphabet_chars[source[idx] >> 2];
155 dest[out_idx + 1] = encoder.alphabet_chars[(source[idx] & 0x3) << 4];
156 out_idx += 2;
157 }
158 if (encoder.pad_char) |pad_char| {
159 for (dest[out_idx..out_len]) |*pad| {
160 pad.* = pad_char;
161 }
162 }
163 return dest[0..out_len];
164 }
165};
166
167pub const Base64Decoder = struct {
168 const invalid_char: u8 = 0xff;
169 const invalid_char_tst: u32 = 0xff000000;
170
171 /// e.g. 'A' => 0.
172 /// `invalid_char` for any value not in the 64 alphabet chars.
173 char_to_index: [256]u8,
174 fast_char_to_index: [4][256]u32,
175 pad_char: ?u8,
176
177 pub fn init(alphabet_chars: [64]u8, pad_char: ?u8) Base64Decoder {
178 var result = Base64Decoder{
179 .char_to_index = [_]u8{invalid_char} ** 256,
180 .fast_char_to_index = .{[_]u32{invalid_char_tst} ** 256} ** 4,
181 .pad_char = pad_char,
182 };
183
184 var char_in_alphabet = [_]bool{false} ** 256;
185 for (alphabet_chars, 0..) |c, i| {
186 assert(!char_in_alphabet[c]);
187 assert(pad_char == null or c != pad_char.?);
188
189 const ci = @as(u32, @intCast(i));
190 result.fast_char_to_index[0][c] = ci << 2;
191 result.fast_char_to_index[1][c] = (ci >> 4) | ((ci & 0x0f) << 12);
192 result.fast_char_to_index[2][c] = ((ci & 0x3) << 22) | ((ci & 0x3c) << 6);
193 result.fast_char_to_index[3][c] = ci << 16;
194
195 result.char_to_index[c] = @as(u8, @intCast(i));
196 char_in_alphabet[c] = true;
197 }
198 return result;
199 }
200
201 /// Return the maximum possible decoded size for a given input length - The actual length may be less if the input includes padding.
202 /// `InvalidPadding` is returned if the input length is not valid.
203 pub fn calcSizeUpperBound(decoder: *const Base64Decoder, source_len: usize) Error!usize {
204 var result = source_len / 4 * 3;
205 const leftover = source_len % 4;
206 if (decoder.pad_char != null) {
207 if (leftover % 4 != 0) return error.InvalidPadding;
208 } else {
209 if (leftover % 4 == 1) return error.InvalidPadding;
210 result += leftover * 3 / 4;
211 }
212 return result;
213 }
214
215 /// Return the exact decoded size for a slice.
216 /// `InvalidPadding` is returned if the input length is not valid.
217 pub fn calcSizeForSlice(decoder: *const Base64Decoder, source: []const u8) Error!usize {
218 const source_len = source.len;
219 var result = try decoder.calcSizeUpperBound(source_len);
220 if (decoder.pad_char) |pad_char| {
221 if (source_len >= 1 and source[source_len - 1] == pad_char) result -= 1;
222 if (source_len >= 2 and source[source_len - 2] == pad_char) result -= 1;
223 }
224 return result;
225 }
226
227 /// dest.len must be what you get from ::calcSize.
228 /// Invalid characters result in `error.InvalidCharacter`.
229 /// Invalid padding results in `error.InvalidPadding`.
230 pub fn decode(decoder: *const Base64Decoder, dest: []u8, source: []const u8) Error!void {
231 if (decoder.pad_char != null and source.len % 4 != 0) return error.InvalidPadding;
232 var dest_idx: usize = 0;
233 var fast_src_idx: usize = 0;
234 var acc: u12 = 0;
235 var acc_len: u4 = 0;
236 var leftover_idx: ?usize = null;
237 while (fast_src_idx + 16 < source.len and dest_idx + 15 < dest.len) : ({
238 fast_src_idx += 16;
239 dest_idx += 12;
240 }) {
241 var bits: u128 = 0;
242 inline for (0..4) |i| {
243 var new_bits: u128 = decoder.fast_char_to_index[0][source[fast_src_idx + i * 4]];
244 new_bits |= decoder.fast_char_to_index[1][source[fast_src_idx + 1 + i * 4]];
245 new_bits |= decoder.fast_char_to_index[2][source[fast_src_idx + 2 + i * 4]];
246 new_bits |= decoder.fast_char_to_index[3][source[fast_src_idx + 3 + i * 4]];
247 if ((new_bits & invalid_char_tst) != 0) return error.InvalidCharacter;
248 bits |= (new_bits << (24 * i));
249 }
250 std.mem.writeInt(u128, dest[dest_idx..][0..16], bits, .little);
251 }
252 while (fast_src_idx + 4 < source.len and dest_idx + 3 < dest.len) : ({
253 fast_src_idx += 4;
254 dest_idx += 3;
255 }) {
256 var bits = decoder.fast_char_to_index[0][source[fast_src_idx]];
257 bits |= decoder.fast_char_to_index[1][source[fast_src_idx + 1]];
258 bits |= decoder.fast_char_to_index[2][source[fast_src_idx + 2]];
259 bits |= decoder.fast_char_to_index[3][source[fast_src_idx + 3]];
260 if ((bits & invalid_char_tst) != 0) return error.InvalidCharacter;
261 std.mem.writeInt(u32, dest[dest_idx..][0..4], bits, .little);
262 }
263 const remaining = source[fast_src_idx..];
264 for (remaining, fast_src_idx..) |c, src_idx| {
265 const d = decoder.char_to_index[c];
266 if (d == invalid_char) {
267 if (decoder.pad_char == null or c != decoder.pad_char.?) return error.InvalidCharacter;
268 leftover_idx = src_idx;
269 break;
270 }
271 acc = (acc << 6) + d;
272 acc_len += 6;
273 if (acc_len >= 8) {
274 acc_len -= 8;
275 dest[dest_idx] = @as(u8, @truncate(acc >> acc_len));
276 dest_idx += 1;
277 }
278 }
279 if (acc_len > 4 or (acc & (@as(u12, 1) << acc_len) - 1) != 0) {
280 return error.InvalidPadding;
281 }
282 if (leftover_idx == null) return;
283 const leftover = source[leftover_idx.?..];
284 if (decoder.pad_char) |pad_char| {
285 const padding_len = acc_len / 2;
286 var padding_chars: usize = 0;
287 for (leftover) |c| {
288 if (c != pad_char) {
289 return if (c == Base64Decoder.invalid_char) error.InvalidCharacter else error.InvalidPadding;
290 }
291 padding_chars += 1;
292 }
293 if (padding_chars != padding_len) return error.InvalidPadding;
294 }
295 }
296};
297
298pub const Base64DecoderWithIgnore = struct {
299 decoder: Base64Decoder,
300 char_is_ignored: [256]bool,
301
302 pub fn init(alphabet_chars: [64]u8, pad_char: ?u8, ignore_chars: []const u8) Base64DecoderWithIgnore {
303 var result = Base64DecoderWithIgnore{
304 .decoder = Base64Decoder.init(alphabet_chars, pad_char),
305 .char_is_ignored = [_]bool{false} ** 256,
306 };
307 for (ignore_chars) |c| {
308 assert(result.decoder.char_to_index[c] == Base64Decoder.invalid_char);
309 assert(!result.char_is_ignored[c]);
310 assert(result.decoder.pad_char != c);
311 result.char_is_ignored[c] = true;
312 }
313 return result;
314 }
315
316 /// Return the maximum possible decoded size for a given input length - The actual length may be
317 /// less if the input includes padding or ignored characters.
318 pub fn calcSizeUpperBound(decoder_with_ignore: *const Base64DecoderWithIgnore, source_len: usize) usize {
319 var result = source_len / 4 * 3;
320 if (decoder_with_ignore.decoder.pad_char == null) {
321 const leftover = source_len % 4;
322 result += leftover * 3 / 4;
323 }
324 return result;
325 }
326
327 /// Invalid characters that are not ignored result in error.InvalidCharacter.
328 /// Invalid padding results in error.InvalidPadding.
329 /// Decoding more data than can fit in dest results in error.NoSpaceLeft. See also ::calcSizeUpperBound.
330 /// Returns the number of bytes written to dest.
331 pub fn decode(decoder_with_ignore: *const Base64DecoderWithIgnore, dest: []u8, source: []const u8) Error!usize {
332 const decoder = &decoder_with_ignore.decoder;
333 var acc: u12 = 0;
334 var acc_len: u4 = 0;
335 var dest_idx: usize = 0;
336 var leftover_idx: ?usize = null;
337 for (source, 0..) |c, src_idx| {
338 if (decoder_with_ignore.char_is_ignored[c]) continue;
339 const d = decoder.char_to_index[c];
340 if (d == Base64Decoder.invalid_char) {
341 if (decoder.pad_char == null or c != decoder.pad_char.?) return error.InvalidCharacter;
342 leftover_idx = src_idx;
343 break;
344 }
345 acc = (acc << 6) + d;
346 acc_len += 6;
347 if (acc_len >= 8) {
348 if (dest_idx == dest.len) return error.NoSpaceLeft;
349 acc_len -= 8;
350 dest[dest_idx] = @as(u8, @truncate(acc >> acc_len));
351 dest_idx += 1;
352 }
353 }
354 if (acc_len > 4 or (acc & (@as(u12, 1) << acc_len) - 1) != 0) {
355 return error.InvalidPadding;
356 }
357 const padding_len = acc_len / 2;
358 if (leftover_idx == null) {
359 if (decoder.pad_char != null and padding_len != 0) return error.InvalidPadding;
360 return dest_idx;
361 }
362 const leftover = source[leftover_idx.?..];
363 if (decoder.pad_char) |pad_char| {
364 var padding_chars: usize = 0;
365 for (leftover) |c| {
366 if (decoder_with_ignore.char_is_ignored[c]) continue;
367 if (c != pad_char) {
368 return if (c == Base64Decoder.invalid_char) error.InvalidCharacter else error.InvalidPadding;
369 }
370 padding_chars += 1;
371 }
372 if (padding_chars != padding_len) return error.InvalidPadding;
373 }
374 return dest_idx;
375 }
376};
377
378test "base64" {
379 @setEvalBranchQuota(8000);
380 try testBase64();
381 try comptime testAllApis(standard, "comptime", "Y29tcHRpbWU=");
382}
383
384test "base64 padding dest overflow" {
385 const input = "foo";
386
387 var expect: [128]u8 = undefined;
388 @memset(&expect, 0);
389 _ = url_safe.Encoder.encode(expect[0..url_safe.Encoder.calcSize(input.len)], input);
390
391 var got: [128]u8 = undefined;
392 @memset(&got, 0);
393 _ = url_safe.Encoder.encode(&got, input);
394
395 try std.testing.expectEqualSlices(u8, &expect, &got);
396}
397
398test "base64 url_safe_no_pad" {
399 @setEvalBranchQuota(8000);
400 try testBase64UrlSafeNoPad();
401 try comptime testAllApis(url_safe_no_pad, "comptime", "Y29tcHRpbWU");
402}
403
404fn testBase64() !void {
405 const codecs = standard;
406
407 try testAllApis(codecs, "", "");
408 try testAllApis(codecs, "f", "Zg==");
409 try testAllApis(codecs, "fo", "Zm8=");
410 try testAllApis(codecs, "foo", "Zm9v");
411 try testAllApis(codecs, "foob", "Zm9vYg==");
412 try testAllApis(codecs, "fooba", "Zm9vYmE=");
413 try testAllApis(codecs, "foobar", "Zm9vYmFy");
414 try testAllApis(codecs, "foobarfoobarfoo", "Zm9vYmFyZm9vYmFyZm9v");
415 try testAllApis(codecs, "foobarfoobarfoob", "Zm9vYmFyZm9vYmFyZm9vYg==");
416 try testAllApis(codecs, "foobarfoobarfooba", "Zm9vYmFyZm9vYmFyZm9vYmE=");
417 try testAllApis(codecs, "foobarfoobarfoobar", "Zm9vYmFyZm9vYmFyZm9vYmFy");
418
419 try testDecodeIgnoreSpace(codecs, "", " ");
420 try testDecodeIgnoreSpace(codecs, "f", "Z g= =");
421 try testDecodeIgnoreSpace(codecs, "fo", " Zm8=");
422 try testDecodeIgnoreSpace(codecs, "foo", "Zm9v ");
423 try testDecodeIgnoreSpace(codecs, "foob", "Zm9vYg = = ");
424 try testDecodeIgnoreSpace(codecs, "fooba", "Zm9v YmE=");
425 try testDecodeIgnoreSpace(codecs, "foobar", " Z m 9 v Y m F y ");
426
427 // test getting some api errors
428 try testError(codecs, "A", error.InvalidPadding);
429 try testError(codecs, "AA", error.InvalidPadding);
430 try testError(codecs, "AAA", error.InvalidPadding);
431 try testError(codecs, "A..A", error.InvalidCharacter);
432 try testError(codecs, "AA=A", error.InvalidPadding);
433 try testError(codecs, "AA/=", error.InvalidPadding);
434 try testError(codecs, "A/==", error.InvalidPadding);
435 try testError(codecs, "A===", error.InvalidPadding);
436 try testError(codecs, "====", error.InvalidPadding);
437 try testError(codecs, "Zm9vYmFyZm9vYmFyA..A", error.InvalidCharacter);
438 try testError(codecs, "Zm9vYmFyZm9vYmFyAA=A", error.InvalidPadding);
439 try testError(codecs, "Zm9vYmFyZm9vYmFyAA/=", error.InvalidPadding);
440 try testError(codecs, "Zm9vYmFyZm9vYmFyA/==", error.InvalidPadding);
441 try testError(codecs, "Zm9vYmFyZm9vYmFyA===", error.InvalidPadding);
442 try testError(codecs, "A..AZm9vYmFyZm9vYmFy", error.InvalidCharacter);
443 try testError(codecs, "Zm9vYmFyZm9vAA=A", error.InvalidPadding);
444 try testError(codecs, "Zm9vYmFyZm9vAA/=", error.InvalidPadding);
445 try testError(codecs, "Zm9vYmFyZm9vA/==", error.InvalidPadding);
446 try testError(codecs, "Zm9vYmFyZm9vA===", error.InvalidPadding);
447
448 try testNoSpaceLeftError(codecs, "AA==");
449 try testNoSpaceLeftError(codecs, "AAA=");
450 try testNoSpaceLeftError(codecs, "AAAA");
451 try testNoSpaceLeftError(codecs, "AAAAAA==");
452
453 try testFourBytesDestNoSpaceLeftError(codecs, "AAAAAAAAAAAAAAAA");
454}
455
456fn testBase64UrlSafeNoPad() !void {
457 const codecs = url_safe_no_pad;
458
459 try testAllApis(codecs, "", "");
460 try testAllApis(codecs, "f", "Zg");
461 try testAllApis(codecs, "fo", "Zm8");
462 try testAllApis(codecs, "foo", "Zm9v");
463 try testAllApis(codecs, "foob", "Zm9vYg");
464 try testAllApis(codecs, "fooba", "Zm9vYmE");
465 try testAllApis(codecs, "foobar", "Zm9vYmFy");
466 try testAllApis(codecs, "foobarfoobarfoobar", "Zm9vYmFyZm9vYmFyZm9vYmFy");
467
468 try testDecodeIgnoreSpace(codecs, "", " ");
469 try testDecodeIgnoreSpace(codecs, "f", "Z g ");
470 try testDecodeIgnoreSpace(codecs, "fo", " Zm8");
471 try testDecodeIgnoreSpace(codecs, "foo", "Zm9v ");
472 try testDecodeIgnoreSpace(codecs, "foob", "Zm9vYg ");
473 try testDecodeIgnoreSpace(codecs, "fooba", "Zm9v YmE");
474 try testDecodeIgnoreSpace(codecs, "foobar", " Z m 9 v Y m F y ");
475
476 // test getting some api errors
477 try testError(codecs, "A", error.InvalidPadding);
478 try testError(codecs, "AAA=", error.InvalidCharacter);
479 try testError(codecs, "A..A", error.InvalidCharacter);
480 try testError(codecs, "AA=A", error.InvalidCharacter);
481 try testError(codecs, "AA/=", error.InvalidCharacter);
482 try testError(codecs, "A/==", error.InvalidCharacter);
483 try testError(codecs, "A===", error.InvalidCharacter);
484 try testError(codecs, "====", error.InvalidCharacter);
485 try testError(codecs, "Zm9vYmFyZm9vYmFyA..A", error.InvalidCharacter);
486 try testError(codecs, "A..AZm9vYmFyZm9vYmFy", error.InvalidCharacter);
487
488 try testNoSpaceLeftError(codecs, "AA");
489 try testNoSpaceLeftError(codecs, "AAA");
490 try testNoSpaceLeftError(codecs, "AAAA");
491 try testNoSpaceLeftError(codecs, "AAAAAA");
492
493 try testFourBytesDestNoSpaceLeftError(codecs, "AAAAAAAAAAAAAAAA");
494}
495
496fn testAllApis(codecs: Codecs, expected_decoded: []const u8, expected_encoded: []const u8) !void {
497 // Base64Encoder
498 {
499 // raw encode
500 var buffer: [0x100]u8 = undefined;
501 const encoded = codecs.Encoder.encode(&buffer, expected_decoded);
502 try testing.expectEqualSlices(u8, expected_encoded, encoded);
503 }
504 {
505 // stream encode
506 var buffer: [0x100]u8 = undefined;
507 var writer: std.Io.Writer = .fixed(&buffer);
508 try codecs.Encoder.encodeWriter(&writer, expected_decoded);
509 try testing.expectEqualSlices(u8, expected_encoded, writer.buffered());
510 }
511
512 // Base64Decoder
513 {
514 var buffer: [0x100]u8 = undefined;
515 const decoded = buffer[0..try codecs.Decoder.calcSizeForSlice(expected_encoded)];
516 try codecs.Decoder.decode(decoded, expected_encoded);
517 try testing.expectEqualSlices(u8, expected_decoded, decoded);
518 }
519
520 // Base64DecoderWithIgnore
521 {
522 const decoder_ignore_nothing = codecs.decoderWithIgnore("");
523 var buffer: [0x100]u8 = undefined;
524 const decoded = buffer[0..decoder_ignore_nothing.calcSizeUpperBound(expected_encoded.len)];
525 const written = try decoder_ignore_nothing.decode(decoded, expected_encoded);
526 try testing.expect(written <= decoded.len);
527 try testing.expectEqualSlices(u8, expected_decoded, decoded[0..written]);
528 }
529}
530
531fn testDecodeIgnoreSpace(codecs: Codecs, expected_decoded: []const u8, encoded: []const u8) !void {
532 const decoder_ignore_space = codecs.decoderWithIgnore(" ");
533 var buffer: [0x100]u8 = undefined;
534 const decoded = buffer[0..decoder_ignore_space.calcSizeUpperBound(encoded.len)];
535 const written = try decoder_ignore_space.decode(decoded, encoded);
536 try testing.expectEqualSlices(u8, expected_decoded, decoded[0..written]);
537}
538
539fn testError(codecs: Codecs, encoded: []const u8, expected_err: anyerror) !void {
540 const decoder_ignore_space = codecs.decoderWithIgnore(" ");
541 var buffer: [0x100]u8 = undefined;
542 if (codecs.Decoder.calcSizeForSlice(encoded)) |decoded_size| {
543 const decoded = buffer[0..decoded_size];
544 if (codecs.Decoder.decode(decoded, encoded)) |_| {
545 return error.ExpectedError;
546 } else |err| if (err != expected_err) return err;
547 } else |err| if (err != expected_err) return err;
548
549 if (decoder_ignore_space.decode(buffer[0..], encoded)) |_| {
550 return error.ExpectedError;
551 } else |err| if (err != expected_err) return err;
552}
553
554fn testNoSpaceLeftError(codecs: Codecs, encoded: []const u8) !void {
555 const decoder_ignore_space = codecs.decoderWithIgnore(" ");
556 var buffer: [0x100]u8 = undefined;
557 const decoded = buffer[0 .. (try codecs.Decoder.calcSizeForSlice(encoded)) - 1];
558 if (decoder_ignore_space.decode(decoded, encoded)) |_| {
559 return error.ExpectedError;
560 } else |err| if (err != error.NoSpaceLeft) return err;
561}
562
563fn testFourBytesDestNoSpaceLeftError(codecs: Codecs, encoded: []const u8) !void {
564 const decoder_ignore_space = codecs.decoderWithIgnore(" ");
565 var buffer: [0x100]u8 = undefined;
566 const decoded = buffer[0..4];
567 if (decoder_ignore_space.decode(decoded, encoded)) |_| {
568 return error.ExpectedError;
569 } else |err| if (err != error.NoSpaceLeft) return err;
570}