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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-15 20:01:36 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-15 20:01:36 +0000 |
commit | 62e4c68907d8d33709c2c1f92a161dff00b3d5f2 (patch) | |
tree | adbbaf3acf88ea08f6eeec4b75ee98ad3b07fbdc /src/third-party/base64/lib/arch/generic/64 | |
parent | Initial commit. (diff) | |
download | lnav-upstream/0.11.2.tar.xz lnav-upstream/0.11.2.zip |
Adding upstream version 0.11.2.upstream/0.11.2
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/third-party/base64/lib/arch/generic/64')
-rw-r--r-- | src/third-party/base64/lib/arch/generic/64/enc_loop.c | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/src/third-party/base64/lib/arch/generic/64/enc_loop.c b/src/third-party/base64/lib/arch/generic/64/enc_loop.c new file mode 100644 index 0000000..0840bc7 --- /dev/null +++ b/src/third-party/base64/lib/arch/generic/64/enc_loop.c @@ -0,0 +1,77 @@ +static inline void +enc_loop_generic_64_inner (const uint8_t **s, uint8_t **o) +{ + uint64_t src; + + // Load input: + memcpy(&src, *s, sizeof (src)); + + // Reorder to 64-bit big-endian, if not already in that format. The + // workset must be in big-endian, otherwise the shifted bits do not + // carry over properly among adjacent bytes: + src = BASE64_HTOBE64(src); + + // Four indices for the 12-bit lookup table: + const size_t index0 = (src >> 52) & 0xFFFU; + const size_t index1 = (src >> 40) & 0xFFFU; + const size_t index2 = (src >> 28) & 0xFFFU; + const size_t index3 = (src >> 16) & 0xFFFU; + + // Table lookup and store: + memcpy(*o + 0, base64_table_enc_12bit + index0, 2); + memcpy(*o + 2, base64_table_enc_12bit + index1, 2); + memcpy(*o + 4, base64_table_enc_12bit + index2, 2); + memcpy(*o + 6, base64_table_enc_12bit + index3, 2); + + *s += 6; + *o += 8; +} + +static inline void +enc_loop_generic_64 (const uint8_t **s, size_t *slen, uint8_t **o, size_t *olen) +{ + if (*slen < 8) { + return; + } + + // Process blocks of 6 bytes at a time. Because blocks are loaded 8 + // bytes at a time, ensure that there will be at least 2 remaining + // bytes after the last round, so that the final read will not pass + // beyond the bounds of the input buffer: + size_t rounds = (*slen - 2) / 6; + + *slen -= rounds * 6; // 6 bytes consumed per round + *olen += rounds * 8; // 8 bytes produced per round + + do { + if (rounds >= 8) { + enc_loop_generic_64_inner(s, o); + enc_loop_generic_64_inner(s, o); + enc_loop_generic_64_inner(s, o); + enc_loop_generic_64_inner(s, o); + enc_loop_generic_64_inner(s, o); + enc_loop_generic_64_inner(s, o); + enc_loop_generic_64_inner(s, o); + enc_loop_generic_64_inner(s, o); + rounds -= 8; + continue; + } + if (rounds >= 4) { + enc_loop_generic_64_inner(s, o); + enc_loop_generic_64_inner(s, o); + enc_loop_generic_64_inner(s, o); + enc_loop_generic_64_inner(s, o); + rounds -= 4; + continue; + } + if (rounds >= 2) { + enc_loop_generic_64_inner(s, o); + enc_loop_generic_64_inner(s, o); + rounds -= 2; + continue; + } + enc_loop_generic_64_inner(s, o); + break; + + } while (rounds > 0); +} |