*/
/*
- * Copyright (C) 2012 Eric Biggers
+ * Copyright (C) 2012, 2013 Eric Biggers
*
* This file is part of wimlib, a library for working with WIM files.
*
* indices into the decoding table, and symbol entries are distinguished from
* pointers by the fact that values less than @num_syms must be symbol values.
*/
-int make_huffman_decode_table(u16 decode_table[], unsigned num_syms,
- unsigned table_bits, const u8 lens[],
- unsigned max_codeword_len)
+int
+make_huffman_decode_table(u16 decode_table[], unsigned num_syms,
+ unsigned table_bits, const u8 lens[],
+ unsigned max_codeword_len)
{
unsigned len_counts[max_codeword_len + 1];
u16 sorted_syms[num_syms];
const unsigned entries_per_long = sizeof(unsigned long) /
sizeof(decode_table[0]);
if (num_entries >= entries_per_long) {
+ /* Fill in the Huffman decode table entries one unsigned
+ * long at a time. On 32-bit systems this is 2 entries
+ * per store, while on 64-bit systems this is 4 entries
+ * per store. */
wimlib_assert2(decode_table_pos % entries_per_long == 0);
BUILD_BUG_ON(sizeof(unsigned long) != 4 &&
sizeof(unsigned long) != 8);
unsigned long v = sym;
if (sizeof(unsigned long) >= 4)
v |= v << 16;
- if (sizeof(unsigned long) >= 8)
+ if (sizeof(unsigned long) >= 8) {
+ /* This may produce a compiler warning if an
+ * unsigned long is 32 bits, but this won't be
+ * executed unless an unsigned long is at least
+ * 64 bits anyway. */
v |= v << 32;
+ }
do {
*p++ = v;
} while (--n);
decode_table_pos += num_entries;
} else {
+ /* Fill in the Huffman decode table entries one 16-bit
+ * integer at a time. */
do {
decode_table[decode_table_pos++] = sym;
} while (--num_entries);
unsigned sym = sorted_syms[i];
unsigned codeword_len = lens[sym];
unsigned extra_bits = codeword_len - table_bits;
- unsigned extra_mask;
cur_codeword <<= (codeword_len - prev_codeword_len);
prev_codeword_len = codeword_len;
/* Reads a Huffman-encoded symbol from the bistream when the number of remaining
* bits is less than the maximum codeword length. */
-int read_huffsym_near_end_of_input(struct input_bitstream *istream,
- const u16 decode_table[],
- const u8 lens[],
- unsigned num_syms,
- unsigned table_bits,
- unsigned *n)
+int
+read_huffsym_near_end_of_input(struct input_bitstream *istream,
+ const u16 decode_table[],
+ const u8 lens[],
+ unsigned num_syms,
+ unsigned table_bits,
+ unsigned *n)
{
unsigned bitsleft = istream->bitsleft;
unsigned key_size;