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-rw-r--r--util/compress/libdeflate/lib/decompress_template.h421
1 files changed, 0 insertions, 421 deletions
diff --git a/util/compress/libdeflate/lib/decompress_template.h b/util/compress/libdeflate/lib/decompress_template.h
deleted file mode 100644
index c6bcf9f52..000000000
--- a/util/compress/libdeflate/lib/decompress_template.h
+++ /dev/null
@@ -1,421 +0,0 @@
-/*
- * decompress_template.h
- *
- * Copyright 2016 Eric Biggers
- *
- * Permission is hereby granted, free of charge, to any person
- * obtaining a copy of this software and associated documentation
- * files (the "Software"), to deal in the Software without
- * restriction, including without limitation the rights to use,
- * copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the
- * Software is furnished to do so, subject to the following
- * conditions:
- *
- * The above copyright notice and this permission notice shall be
- * included in all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
- * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
- * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
- * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
- * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
- * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
- * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
- * OTHER DEALINGS IN THE SOFTWARE.
- */
-
-/*
- * This is the actual DEFLATE decompression routine, lifted out of
- * deflate_decompress.c so that it can be compiled multiple times with different
- * target instruction sets.
- */
-
-static enum libdeflate_result ATTRIBUTES
-FUNCNAME(struct libdeflate_decompressor * restrict d,
- const void * restrict in, size_t in_nbytes,
- void * restrict out, size_t out_nbytes_avail,
- size_t *actual_in_nbytes_ret, size_t *actual_out_nbytes_ret)
-{
- u8 *out_next = out;
- u8 * const out_end = out_next + out_nbytes_avail;
- const u8 *in_next = in;
- const u8 * const in_end = in_next + in_nbytes;
- bitbuf_t bitbuf = 0;
- unsigned bitsleft = 0;
- size_t overrun_count = 0;
- unsigned i;
- unsigned is_final_block;
- unsigned block_type;
- u16 len;
- u16 nlen;
- unsigned num_litlen_syms;
- unsigned num_offset_syms;
- u16 tmp16;
- u32 tmp32;
-
-next_block:
- /* Starting to read the next block. */
- ;
-
- STATIC_ASSERT(CAN_ENSURE(1 + 2 + 5 + 5 + 4));
- ENSURE_BITS(1 + 2 + 5 + 5 + 4);
-
- /* BFINAL: 1 bit */
- is_final_block = POP_BITS(1);
-
- /* BTYPE: 2 bits */
- block_type = POP_BITS(2);
-
- if (block_type == DEFLATE_BLOCKTYPE_DYNAMIC_HUFFMAN) {
-
- /* Dynamic Huffman block. */
-
- /* The order in which precode lengths are stored. */
- static const u8 deflate_precode_lens_permutation[DEFLATE_NUM_PRECODE_SYMS] = {
- 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15
- };
-
- unsigned num_explicit_precode_lens;
-
- /* Read the codeword length counts. */
-
- STATIC_ASSERT(DEFLATE_NUM_LITLEN_SYMS == ((1 << 5) - 1) + 257);
- num_litlen_syms = POP_BITS(5) + 257;
-
- STATIC_ASSERT(DEFLATE_NUM_OFFSET_SYMS == ((1 << 5) - 1) + 1);
- num_offset_syms = POP_BITS(5) + 1;
-
- STATIC_ASSERT(DEFLATE_NUM_PRECODE_SYMS == ((1 << 4) - 1) + 4);
- num_explicit_precode_lens = POP_BITS(4) + 4;
-
- d->static_codes_loaded = false;
-
- /* Read the precode codeword lengths. */
- STATIC_ASSERT(DEFLATE_MAX_PRE_CODEWORD_LEN == (1 << 3) - 1);
- for (i = 0; i < num_explicit_precode_lens; i++) {
- ENSURE_BITS(3);
- d->u.precode_lens[deflate_precode_lens_permutation[i]] = POP_BITS(3);
- }
-
- for (; i < DEFLATE_NUM_PRECODE_SYMS; i++)
- d->u.precode_lens[deflate_precode_lens_permutation[i]] = 0;
-
- /* Build the decode table for the precode. */
- SAFETY_CHECK(build_precode_decode_table(d));
-
- /* Expand the literal/length and offset codeword lengths. */
- for (i = 0; i < num_litlen_syms + num_offset_syms; ) {
- u32 entry;
- unsigned presym;
- u8 rep_val;
- unsigned rep_count;
-
- ENSURE_BITS(DEFLATE_MAX_PRE_CODEWORD_LEN + 7);
-
- /* (The code below assumes that the precode decode table
- * does not have any subtables.) */
- STATIC_ASSERT(PRECODE_TABLEBITS == DEFLATE_MAX_PRE_CODEWORD_LEN);
-
- /* Read the next precode symbol. */
- entry = d->u.l.precode_decode_table[BITS(DEFLATE_MAX_PRE_CODEWORD_LEN)];
- REMOVE_BITS(entry & HUFFDEC_LENGTH_MASK);
- presym = entry >> HUFFDEC_RESULT_SHIFT;
-
- if (presym < 16) {
- /* Explicit codeword length */
- d->u.l.lens[i++] = presym;
- continue;
- }
-
- /* Run-length encoded codeword lengths */
-
- /* Note: we don't need verify that the repeat count
- * doesn't overflow the number of elements, since we
- * have enough extra spaces to allow for the worst-case
- * overflow (138 zeroes when only 1 length was
- * remaining).
- *
- * In the case of the small repeat counts (presyms 16
- * and 17), it is fastest to always write the maximum
- * number of entries. That gets rid of branches that
- * would otherwise be required.
- *
- * It is not just because of the numerical order that
- * our checks go in the order 'presym < 16', 'presym ==
- * 16', and 'presym == 17'. For typical data this is
- * ordered from most frequent to least frequent case.
- */
- STATIC_ASSERT(DEFLATE_MAX_LENS_OVERRUN == 138 - 1);
-
- if (presym == 16) {
- /* Repeat the previous length 3 - 6 times */
- SAFETY_CHECK(i != 0);
- rep_val = d->u.l.lens[i - 1];
- STATIC_ASSERT(3 + ((1 << 2) - 1) == 6);
- rep_count = 3 + POP_BITS(2);
- d->u.l.lens[i + 0] = rep_val;
- d->u.l.lens[i + 1] = rep_val;
- d->u.l.lens[i + 2] = rep_val;
- d->u.l.lens[i + 3] = rep_val;
- d->u.l.lens[i + 4] = rep_val;
- d->u.l.lens[i + 5] = rep_val;
- i += rep_count;
- } else if (presym == 17) {
- /* Repeat zero 3 - 10 times */
- STATIC_ASSERT(3 + ((1 << 3) - 1) == 10);
- rep_count = 3 + POP_BITS(3);
- d->u.l.lens[i + 0] = 0;
- d->u.l.lens[i + 1] = 0;
- d->u.l.lens[i + 2] = 0;
- d->u.l.lens[i + 3] = 0;
- d->u.l.lens[i + 4] = 0;
- d->u.l.lens[i + 5] = 0;
- d->u.l.lens[i + 6] = 0;
- d->u.l.lens[i + 7] = 0;
- d->u.l.lens[i + 8] = 0;
- d->u.l.lens[i + 9] = 0;
- i += rep_count;
- } else {
- /* Repeat zero 11 - 138 times */
- STATIC_ASSERT(11 + ((1 << 7) - 1) == 138);
- rep_count = 11 + POP_BITS(7);
- memset(&d->u.l.lens[i], 0,
- rep_count * sizeof(d->u.l.lens[i]));
- i += rep_count;
- }
- }
- } else if (block_type == DEFLATE_BLOCKTYPE_UNCOMPRESSED) {
-
- /* Uncompressed block: copy 'len' bytes literally from the input
- * buffer to the output buffer. */
-
- ALIGN_INPUT();
-
- SAFETY_CHECK(in_end - in_next >= 4);
-
- len = READ_U16();
- nlen = READ_U16();
-
- SAFETY_CHECK(len == (u16)~nlen);
- if (unlikely(len > out_end - out_next))
- return LIBDEFLATE_INSUFFICIENT_SPACE;
- SAFETY_CHECK(len <= in_end - in_next);
-
- memcpy(out_next, in_next, len);
- in_next += len;
- out_next += len;
-
- goto block_done;
-
- } else {
- SAFETY_CHECK(block_type == DEFLATE_BLOCKTYPE_STATIC_HUFFMAN);
-
- /*
- * Static Huffman block: build the decode tables for the static
- * codes. Skip doing so if the tables are already set up from
- * an earlier static block; this speeds up decompression of
- * degenerate input of many empty or very short static blocks.
- *
- * Afterwards, the remainder is the same as decompressing a
- * dynamic Huffman block.
- */
-
- if (d->static_codes_loaded)
- goto have_decode_tables;
-
- d->static_codes_loaded = true;
-
- STATIC_ASSERT(DEFLATE_NUM_LITLEN_SYMS == 288);
- STATIC_ASSERT(DEFLATE_NUM_OFFSET_SYMS == 32);
-
- for (i = 0; i < 144; i++)
- d->u.l.lens[i] = 8;
- for (; i < 256; i++)
- d->u.l.lens[i] = 9;
- for (; i < 280; i++)
- d->u.l.lens[i] = 7;
- for (; i < 288; i++)
- d->u.l.lens[i] = 8;
-
- for (; i < 288 + 32; i++)
- d->u.l.lens[i] = 5;
-
- num_litlen_syms = 288;
- num_offset_syms = 32;
- }
-
- /* Decompressing a Huffman block (either dynamic or static) */
-
- SAFETY_CHECK(build_offset_decode_table(d, num_litlen_syms, num_offset_syms));
- SAFETY_CHECK(build_litlen_decode_table(d, num_litlen_syms, num_offset_syms));
-have_decode_tables:
-
- /* The main DEFLATE decode loop */
- for (;;) {
- u32 entry;
- u32 length;
- u32 offset;
- const u8 *src;
- u8 *dst;
-
- /* Decode a litlen symbol. */
- ENSURE_BITS(DEFLATE_MAX_LITLEN_CODEWORD_LEN);
- entry = d->u.litlen_decode_table[BITS(LITLEN_TABLEBITS)];
- if (entry & HUFFDEC_SUBTABLE_POINTER) {
- /* Litlen subtable required (uncommon case) */
- REMOVE_BITS(LITLEN_TABLEBITS);
- entry = d->u.litlen_decode_table[
- ((entry >> HUFFDEC_RESULT_SHIFT) & 0xFFFF) +
- BITS(entry & HUFFDEC_LENGTH_MASK)];
- }
- REMOVE_BITS(entry & HUFFDEC_LENGTH_MASK);
- if (entry & HUFFDEC_LITERAL) {
- /* Literal */
- if (unlikely(out_next == out_end))
- return LIBDEFLATE_INSUFFICIENT_SPACE;
- *out_next++ = (u8)(entry >> HUFFDEC_RESULT_SHIFT);
- continue;
- }
-
- /* Match or end-of-block */
-
- entry >>= HUFFDEC_RESULT_SHIFT;
- ENSURE_BITS(MAX_ENSURE);
-
- /* Pop the extra length bits and add them to the length base to
- * produce the full length. */
- length = (entry >> HUFFDEC_LENGTH_BASE_SHIFT) +
- POP_BITS(entry & HUFFDEC_EXTRA_LENGTH_BITS_MASK);
-
- /* The match destination must not end after the end of the
- * output buffer. For efficiency, combine this check with the
- * end-of-block check. We're using 0 for the special
- * end-of-block length, so subtract 1 and it turn it into
- * SIZE_MAX. */
- STATIC_ASSERT(HUFFDEC_END_OF_BLOCK_LENGTH == 0);
- if (unlikely((size_t)length - 1 >= out_end - out_next)) {
- if (unlikely(length != HUFFDEC_END_OF_BLOCK_LENGTH))
- return LIBDEFLATE_INSUFFICIENT_SPACE;
- goto block_done;
- }
-
- /* Decode the match offset. */
-
- entry = d->offset_decode_table[BITS(OFFSET_TABLEBITS)];
- if (entry & HUFFDEC_SUBTABLE_POINTER) {
- /* Offset subtable required (uncommon case) */
- REMOVE_BITS(OFFSET_TABLEBITS);
- entry = d->offset_decode_table[
- ((entry >> HUFFDEC_RESULT_SHIFT) & 0xFFFF) +
- BITS(entry & HUFFDEC_LENGTH_MASK)];
- }
- REMOVE_BITS(entry & HUFFDEC_LENGTH_MASK);
- entry >>= HUFFDEC_RESULT_SHIFT;
-
- STATIC_ASSERT(CAN_ENSURE(DEFLATE_MAX_EXTRA_LENGTH_BITS +
- DEFLATE_MAX_OFFSET_CODEWORD_LEN) &&
- CAN_ENSURE(DEFLATE_MAX_EXTRA_OFFSET_BITS));
- if (!CAN_ENSURE(DEFLATE_MAX_EXTRA_LENGTH_BITS +
- DEFLATE_MAX_OFFSET_CODEWORD_LEN +
- DEFLATE_MAX_EXTRA_OFFSET_BITS))
- ENSURE_BITS(DEFLATE_MAX_EXTRA_OFFSET_BITS);
-
- /* Pop the extra offset bits and add them to the offset base to
- * produce the full offset. */
- offset = (entry & HUFFDEC_OFFSET_BASE_MASK) +
- POP_BITS(entry >> HUFFDEC_EXTRA_OFFSET_BITS_SHIFT);
-
- /* The match source must not begin before the beginning of the
- * output buffer. */
- SAFETY_CHECK(offset <= out_next - (const u8 *)out);
-
- /*
- * Copy the match: 'length' bytes at 'out_next - offset' to
- * 'out_next', possibly overlapping. If the match doesn't end
- * too close to the end of the buffer and offset >= WORDBYTES ||
- * offset == 1, take a fast path which copies a word at a time
- * -- potentially more than the length of the match, but that's
- * fine as long as we check for enough extra space.
- *
- * The remaining cases are not performance-critical so are
- * handled by a simple byte-by-byte copy.
- */
-
- src = out_next - offset;
- dst = out_next;
- out_next += length;
-
- if (UNALIGNED_ACCESS_IS_FAST &&
- /* max overrun is writing 3 words for a min length match */
- likely(out_end - out_next >=
- 3 * WORDBYTES - DEFLATE_MIN_MATCH_LEN)) {
- if (offset >= WORDBYTES) { /* words don't overlap? */
- copy_word_unaligned(src, dst);
- src += WORDBYTES;
- dst += WORDBYTES;
- copy_word_unaligned(src, dst);
- src += WORDBYTES;
- dst += WORDBYTES;
- do {
- copy_word_unaligned(src, dst);
- src += WORDBYTES;
- dst += WORDBYTES;
- } while (dst < out_next);
- } else if (offset == 1) {
- /* RLE encoding of previous byte, common if the
- * data contains many repeated bytes */
- machine_word_t v = repeat_byte(*src);
-
- store_word_unaligned(v, dst);
- dst += WORDBYTES;
- store_word_unaligned(v, dst);
- dst += WORDBYTES;
- do {
- store_word_unaligned(v, dst);
- dst += WORDBYTES;
- } while (dst < out_next);
- } else {
- *dst++ = *src++;
- *dst++ = *src++;
- do {
- *dst++ = *src++;
- } while (dst < out_next);
- }
- } else {
- STATIC_ASSERT(DEFLATE_MIN_MATCH_LEN == 3);
- *dst++ = *src++;
- *dst++ = *src++;
- do {
- *dst++ = *src++;
- } while (dst < out_next);
- }
- }
-
-block_done:
- /* Finished decoding a block. */
-
- if (!is_final_block)
- goto next_block;
-
- /* That was the last block. */
-
- /* Discard any readahead bits and check for excessive overread */
- ALIGN_INPUT();
-
- /* Optionally return the actual number of bytes read */
- if (actual_in_nbytes_ret)
- *actual_in_nbytes_ret = in_next - (u8 *)in;
-
- /* Optionally return the actual number of bytes written */
- if (actual_out_nbytes_ret) {
- *actual_out_nbytes_ret = out_next - (u8 *)out;
- } else {
- if (out_next != out_end)
- return LIBDEFLATE_SHORT_OUTPUT;
- }
- return LIBDEFLATE_SUCCESS;
-}
-
-#undef FUNCNAME
-#undef ATTRIBUTES
generated by cgit v1.2.3 (git 2.44.0) at 2024-05-05 10:08:47 +0000