Bug Summary

File:out/../deps/brotli/c/dec/huffman.c
Warning:line 145, column 12
2nd function call argument is an uninitialized value

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-unknown-linux-gnu -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name huffman.c -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model pic -pic-level 2 -pic-is-pie -mframe-pointer=all -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fcoverage-compilation-dir=/home/maurizio/node-v18.6.0/out -resource-dir /usr/local/lib/clang/16.0.0 -D V8_DEPRECATION_WARNINGS -D V8_IMMINENT_DEPRECATION_WARNINGS -D _GLIBCXX_USE_CXX11_ABI=1 -D NODE_OPENSSL_CONF_NAME=nodejs_conf -D NODE_OPENSSL_HAS_QUIC -D __STDC_FORMAT_MACROS -D OPENSSL_NO_PINSHARED -D OPENSSL_THREADS -D OS_LINUX -I ../deps/brotli/c/include -internal-isystem /usr/local/lib/clang/16.0.0/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-redhat-linux/8/../../../../x86_64-redhat-linux/include -internal-externc-isystem /include -internal-externc-isystem /usr/include -O3 -Wno-unused-parameter -fdebug-compilation-dir=/home/maurizio/node-v18.6.0/out -ferror-limit 19 -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -analyzer-output=html -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2022-08-22-142216-507842-1 -x c ../deps/brotli/c/dec/huffman.c
1/* Copyright 2013 Google Inc. All Rights Reserved.
2
3 Distributed under MIT license.
4 See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
5*/
6
7/* Utilities for building Huffman decoding tables. */
8
9#include "./huffman.h"
10
11#include <string.h> /* memcpy, memset */
12
13#include "../common/constants.h"
14#include "../common/platform.h"
15#include <brotli/types.h>
16
17#if defined(__cplusplus) || defined(c_plusplus)
18extern "C" {
19#endif
20
21#define BROTLI_REVERSE_BITS_MAX8 8
22
23#if defined(BROTLI_RBIT)
24#define BROTLI_REVERSE_BITS_BASE0 \
25 ((sizeof(brotli_reg_tuint64_t) << 3) - BROTLI_REVERSE_BITS_MAX8)
26#else
27#define BROTLI_REVERSE_BITS_BASE0 0
28static uint8_t kReverseBits[1 << BROTLI_REVERSE_BITS_MAX8] = {
29 0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0,
30 0x10, 0x90, 0x50, 0xD0, 0x30, 0xB0, 0x70, 0xF0,
31 0x08, 0x88, 0x48, 0xC8, 0x28, 0xA8, 0x68, 0xE8,
32 0x18, 0x98, 0x58, 0xD8, 0x38, 0xB8, 0x78, 0xF8,
33 0x04, 0x84, 0x44, 0xC4, 0x24, 0xA4, 0x64, 0xE4,
34 0x14, 0x94, 0x54, 0xD4, 0x34, 0xB4, 0x74, 0xF4,
35 0x0C, 0x8C, 0x4C, 0xCC, 0x2C, 0xAC, 0x6C, 0xEC,
36 0x1C, 0x9C, 0x5C, 0xDC, 0x3C, 0xBC, 0x7C, 0xFC,
37 0x02, 0x82, 0x42, 0xC2, 0x22, 0xA2, 0x62, 0xE2,
38 0x12, 0x92, 0x52, 0xD2, 0x32, 0xB2, 0x72, 0xF2,
39 0x0A, 0x8A, 0x4A, 0xCA, 0x2A, 0xAA, 0x6A, 0xEA,
40 0x1A, 0x9A, 0x5A, 0xDA, 0x3A, 0xBA, 0x7A, 0xFA,
41 0x06, 0x86, 0x46, 0xC6, 0x26, 0xA6, 0x66, 0xE6,
42 0x16, 0x96, 0x56, 0xD6, 0x36, 0xB6, 0x76, 0xF6,
43 0x0E, 0x8E, 0x4E, 0xCE, 0x2E, 0xAE, 0x6E, 0xEE,
44 0x1E, 0x9E, 0x5E, 0xDE, 0x3E, 0xBE, 0x7E, 0xFE,
45 0x01, 0x81, 0x41, 0xC1, 0x21, 0xA1, 0x61, 0xE1,
46 0x11, 0x91, 0x51, 0xD1, 0x31, 0xB1, 0x71, 0xF1,
47 0x09, 0x89, 0x49, 0xC9, 0x29, 0xA9, 0x69, 0xE9,
48 0x19, 0x99, 0x59, 0xD9, 0x39, 0xB9, 0x79, 0xF9,
49 0x05, 0x85, 0x45, 0xC5, 0x25, 0xA5, 0x65, 0xE5,
50 0x15, 0x95, 0x55, 0xD5, 0x35, 0xB5, 0x75, 0xF5,
51 0x0D, 0x8D, 0x4D, 0xCD, 0x2D, 0xAD, 0x6D, 0xED,
52 0x1D, 0x9D, 0x5D, 0xDD, 0x3D, 0xBD, 0x7D, 0xFD,
53 0x03, 0x83, 0x43, 0xC3, 0x23, 0xA3, 0x63, 0xE3,
54 0x13, 0x93, 0x53, 0xD3, 0x33, 0xB3, 0x73, 0xF3,
55 0x0B, 0x8B, 0x4B, 0xCB, 0x2B, 0xAB, 0x6B, 0xEB,
56 0x1B, 0x9B, 0x5B, 0xDB, 0x3B, 0xBB, 0x7B, 0xFB,
57 0x07, 0x87, 0x47, 0xC7, 0x27, 0xA7, 0x67, 0xE7,
58 0x17, 0x97, 0x57, 0xD7, 0x37, 0xB7, 0x77, 0xF7,
59 0x0F, 0x8F, 0x4F, 0xCF, 0x2F, 0xAF, 0x6F, 0xEF,
60 0x1F, 0x9F, 0x5F, 0xDF, 0x3F, 0xBF, 0x7F, 0xFF
61};
62#endif /* BROTLI_RBIT */
63
64#define BROTLI_REVERSE_BITS_LOWEST((uint64_t)1 << (8 - 1 + 0)) \
65 ((brotli_reg_tuint64_t)1 << (BROTLI_REVERSE_BITS_MAX8 - 1 + BROTLI_REVERSE_BITS_BASE0))
66
67/* Returns reverse(num >> BROTLI_REVERSE_BITS_BASE, BROTLI_REVERSE_BITS_MAX),
68 where reverse(value, len) is the bit-wise reversal of the len least
69 significant bits of value. */
70static BROTLI_INLINEinline __attribute__((__always_inline__)) brotli_reg_tuint64_t BrotliReverseBits(brotli_reg_tuint64_t num) {
71#if defined(BROTLI_RBIT)
72 return BROTLI_RBIT(num);
73#else
74 return kReverseBits[num];
75#endif
76}
77
78/* Stores code in table[0], table[step], table[2*step], ..., table[end] */
79/* Assumes that end is an integer multiple of step */
80static BROTLI_INLINEinline __attribute__((__always_inline__)) void ReplicateValue(HuffmanCode* table,
81 int step, int end,
82 HuffmanCode code) {
83 do {
84 end -= step;
85 table[end] = code;
86 } while (end > 0);
87}
88
89/* Returns the table width of the next 2nd level table. |count| is the histogram
90 of bit lengths for the remaining symbols, |len| is the code length of the
91 next processed symbol. */
92static BROTLI_INLINEinline __attribute__((__always_inline__)) int NextTableBitSize(const uint16_t* const count,
93 int len, int root_bits) {
94 int left = 1 << (len - root_bits);
95 while (len < BROTLI_HUFFMAN_MAX_CODE_LENGTH15) {
96 left -= count[len];
97 if (left <= 0) break;
98 ++len;
99 left <<= 1;
100 }
101 return len - root_bits;
102}
103
104void BrotliBuildCodeLengthsHuffmanTable(HuffmanCode* table,
105 const uint8_t* const code_lengths,
106 uint16_t* count) {
107 HuffmanCode code; /* current table entry */
108 int symbol; /* symbol index in original or sorted table */
109 brotli_reg_tuint64_t key; /* prefix code */
110 brotli_reg_tuint64_t key_step; /* prefix code addend */
111 int step; /* step size to replicate values in current table */
112 int table_size; /* size of current table */
113 int sorted[BROTLI_CODE_LENGTH_CODES(17 + 1)]; /* symbols sorted by code length */
114 /* offsets in sorted table for each length */
115 int offset[BROTLI_HUFFMAN_MAX_CODE_LENGTH_CODE_LENGTH5 + 1];
116 int bits;
117 int bits_count;
118 BROTLI_DCHECK(BROTLI_HUFFMAN_MAX_CODE_LENGTH_CODE_LENGTH <=
119 BROTLI_REVERSE_BITS_MAX);
120
121 /* Generate offsets into sorted symbol table by code length. */
122 symbol = -1;
123 bits = 1;
124 BROTLI_REPEAT(BROTLI_HUFFMAN_MAX_CODE_LENGTH_CODE_LENGTH, {{ if ((5 & 1) != 0) {{ symbol += count[bits]; offset[bits
] = symbol; bits++; };} if ((5 & 2) != 0) {{ symbol += count
[bits]; offset[bits] = symbol; bits++; }; { symbol += count[bits
]; offset[bits] = symbol; bits++; };} if ((5 & 4) != 0) {
{ symbol += count[bits]; offset[bits] = symbol; bits++; }; { symbol
+= count[bits]; offset[bits] = symbol; bits++; }; { symbol +=
count[bits]; offset[bits] = symbol; bits++; }; { symbol += count
[bits]; offset[bits] = symbol; bits++; };} }
1
Taking true branch
→
2
←
Taking false branch
→
3
←
Taking true branch
→
125 symbol += count[bits];{ if ((5 & 1) != 0) {{ symbol += count[bits]; offset[bits
] = symbol; bits++; };} if ((5 & 2) != 0) {{ symbol += count
[bits]; offset[bits] = symbol; bits++; }; { symbol += count[bits
]; offset[bits] = symbol; bits++; };} if ((5 & 4) != 0) {
{ symbol += count[bits]; offset[bits] = symbol; bits++; }; { symbol
+= count[bits]; offset[bits] = symbol; bits++; }; { symbol +=
count[bits]; offset[bits] = symbol; bits++; }; { symbol += count
[bits]; offset[bits] = symbol; bits++; };} }
126 offset[bits] = symbol;{ if ((5 & 1) != 0) {{ symbol += count[bits]; offset[bits
] = symbol; bits++; };} if ((5 & 2) != 0) {{ symbol += count
[bits]; offset[bits] = symbol; bits++; }; { symbol += count[bits
]; offset[bits] = symbol; bits++; };} if ((5 & 4) != 0) {
{ symbol += count[bits]; offset[bits] = symbol; bits++; }; { symbol
+= count[bits]; offset[bits] = symbol; bits++; }; { symbol +=
count[bits]; offset[bits] = symbol; bits++; }; { symbol += count
[bits]; offset[bits] = symbol; bits++; };} }
127 bits++;{ if ((5 & 1) != 0) {{ symbol += count[bits]; offset[bits
] = symbol; bits++; };} if ((5 & 2) != 0) {{ symbol += count
[bits]; offset[bits] = symbol; bits++; }; { symbol += count[bits
]; offset[bits] = symbol; bits++; };} if ((5 & 4) != 0) {
{ symbol += count[bits]; offset[bits] = symbol; bits++; }; { symbol
+= count[bits]; offset[bits] = symbol; bits++; }; { symbol +=
count[bits]; offset[bits] = symbol; bits++; }; { symbol += count
[bits]; offset[bits] = symbol; bits++; };} }
128 }){ if ((5 & 1) != 0) {{ symbol += count[bits]; offset[bits
] = symbol; bits++; };} if ((5 & 2) != 0) {{ symbol += count
[bits]; offset[bits] = symbol; bits++; }; { symbol += count[bits
]; offset[bits] = symbol; bits++; };} if ((5 & 4) != 0) {
{ symbol += count[bits]; offset[bits] = symbol; bits++; }; { symbol
+= count[bits]; offset[bits] = symbol; bits++; }; { symbol +=
count[bits]; offset[bits] = symbol; bits++; }; { symbol += count
[bits]; offset[bits] = symbol; bits++; };} };
129 /* Symbols with code length 0 are placed after all other symbols. */
130 offset[0] = BROTLI_CODE_LENGTH_CODES(17 + 1) - 1;
131
132 /* Sort symbols by length, by symbol order within each length. */
133 symbol = BROTLI_CODE_LENGTH_CODES(17 + 1);
134 do {
7
←
Loop condition is true. Execution continues on line 135
→
11
←
Loop condition is true. Execution continues on line 135
→
15
←
Loop condition is false. Exiting loop
→
135 BROTLI_REPEAT(6, {{ if ((6 & 1) != 0) {{ symbol--; sorted[offset[code_lengths
[symbol]]--] = symbol; };} if ((6 & 2) != 0) {{ symbol--;
sorted[offset[code_lengths[symbol]]--] = symbol; }; { symbol
--; sorted[offset[code_lengths[symbol]]--] = symbol; };} if (
(6 & 4) != 0) {{ symbol--; sorted[offset[code_lengths[symbol
]]--] = symbol; }; { symbol--; sorted[offset[code_lengths[symbol
]]--] = symbol; }; { symbol--; sorted[offset[code_lengths[symbol
]]--] = symbol; }; { symbol--; sorted[offset[code_lengths[symbol
]]--] = symbol; };} }
4
←
Taking false branch
→
5
←
Taking true branch
→
6
←
Taking true branch
→
8
←
Taking false branch
→
9
←
Taking true branch
→
10
←
Taking true branch
→
12
←
Taking false branch
→
13
←
Taking true branch
→
14
←
Taking true branch
→
136 symbol--;{ if ((6 & 1) != 0) {{ symbol--; sorted[offset[code_lengths
[symbol]]--] = symbol; };} if ((6 & 2) != 0) {{ symbol--;
sorted[offset[code_lengths[symbol]]--] = symbol; }; { symbol
--; sorted[offset[code_lengths[symbol]]--] = symbol; };} if (
(6 & 4) != 0) {{ symbol--; sorted[offset[code_lengths[symbol
]]--] = symbol; }; { symbol--; sorted[offset[code_lengths[symbol
]]--] = symbol; }; { symbol--; sorted[offset[code_lengths[symbol
]]--] = symbol; }; { symbol--; sorted[offset[code_lengths[symbol
]]--] = symbol; };} }
137 sorted[offset[code_lengths[symbol]]--] = symbol;{ if ((6 & 1) != 0) {{ symbol--; sorted[offset[code_lengths
[symbol]]--] = symbol; };} if ((6 & 2) != 0) {{ symbol--;
sorted[offset[code_lengths[symbol]]--] = symbol; }; { symbol
--; sorted[offset[code_lengths[symbol]]--] = symbol; };} if (
(6 & 4) != 0) {{ symbol--; sorted[offset[code_lengths[symbol
]]--] = symbol; }; { symbol--; sorted[offset[code_lengths[symbol
]]--] = symbol; }; { symbol--; sorted[offset[code_lengths[symbol
]]--] = symbol; }; { symbol--; sorted[offset[code_lengths[symbol
]]--] = symbol; };} }
138 }){ if ((6 & 1) != 0) {{ symbol--; sorted[offset[code_lengths
[symbol]]--] = symbol; };} if ((6 & 2) != 0) {{ symbol--;
sorted[offset[code_lengths[symbol]]--] = symbol; }; { symbol
--; sorted[offset[code_lengths[symbol]]--] = symbol; };} if (
(6 & 4) != 0) {{ symbol--; sorted[offset[code_lengths[symbol
]]--] = symbol; }; { symbol--; sorted[offset[code_lengths[symbol
]]--] = symbol; }; { symbol--; sorted[offset[code_lengths[symbol
]]--] = symbol; }; { symbol--; sorted[offset[code_lengths[symbol
]]--] = symbol; };} };
139 } while (symbol != 0);
140
141 table_size = 1 << BROTLI_HUFFMAN_MAX_CODE_LENGTH_CODE_LENGTH5;
142
143 /* Special case: all symbols but one have 0 code length. */
144 if (offset[0] == 0) {
16
←
Assuming the condition is true
→
17
←
Taking true branch
→
145 code = ConstructHuffmanCode(0, (uint16_t)sorted[0]);
18
←
2nd function call argument is an uninitialized value
146 for (key = 0; key < (brotli_reg_tuint64_t)table_size; ++key) {
147 table[key] = code;
148 }
149 return;
150 }
151
152 /* Fill in table. */
153 key = 0;
154 key_step = BROTLI_REVERSE_BITS_LOWEST((uint64_t)1 << (8 - 1 + 0));
155 symbol = 0;
156 bits = 1;
157 step = 2;
158 do {
159 for (bits_count = count[bits]; bits_count != 0; --bits_count) {
160 code = ConstructHuffmanCode((uint8_t)bits, (uint16_t)sorted[symbol++]);
161 ReplicateValue(&table[BrotliReverseBits(key)], step, table_size, code);
162 key += key_step;
163 }
164 step <<= 1;
165 key_step >>= 1;
166 } while (++bits <= BROTLI_HUFFMAN_MAX_CODE_LENGTH_CODE_LENGTH5);
167}
168
169uint32_t BrotliBuildHuffmanTable(HuffmanCode* root_table,
170 int root_bits,
171 const uint16_t* const symbol_lists,
172 uint16_t* count) {
173 HuffmanCode code; /* current table entry */
174 HuffmanCode* table; /* next available space in table */
175 int len; /* current code length */
176 int symbol; /* symbol index in original or sorted table */
177 brotli_reg_tuint64_t key; /* prefix code */
178 brotli_reg_tuint64_t key_step; /* prefix code addend */
179 brotli_reg_tuint64_t sub_key; /* 2nd level table prefix code */
180 brotli_reg_tuint64_t sub_key_step; /* 2nd level table prefix code addend */
181 int step; /* step size to replicate values in current table */
182 int table_bits; /* key length of current table */
183 int table_size; /* size of current table */
184 int total_size; /* sum of root table size and 2nd level table sizes */
185 int max_length = -1;
186 int bits;
187 int bits_count;
188
189 BROTLI_DCHECK(root_bits <= BROTLI_REVERSE_BITS_MAX);
190 BROTLI_DCHECK(BROTLI_HUFFMAN_MAX_CODE_LENGTH - root_bits <=
191 BROTLI_REVERSE_BITS_MAX);
192
193 while (symbol_lists[max_length] == 0xFFFF) max_length--;
194 max_length += BROTLI_HUFFMAN_MAX_CODE_LENGTH15 + 1;
195
196 table = root_table;
197 table_bits = root_bits;
198 table_size = 1 << table_bits;
199 total_size = table_size;
200
201 /* Fill in the root table. Reduce the table size to if possible,
202 and create the repetitions by memcpy. */
203 if (table_bits > max_length) {
204 table_bits = max_length;
205 table_size = 1 << table_bits;
206 }
207 key = 0;
208 key_step = BROTLI_REVERSE_BITS_LOWEST((uint64_t)1 << (8 - 1 + 0));
209 bits = 1;
210 step = 2;
211 do {
212 symbol = bits - (BROTLI_HUFFMAN_MAX_CODE_LENGTH15 + 1);
213 for (bits_count = count[bits]; bits_count != 0; --bits_count) {
214 symbol = symbol_lists[symbol];
215 code = ConstructHuffmanCode((uint8_t)bits, (uint16_t)symbol);
216 ReplicateValue(&table[BrotliReverseBits(key)], step, table_size, code);
217 key += key_step;
218 }
219 step <<= 1;
220 key_step >>= 1;
221 } while (++bits <= table_bits);
222
223 /* If root_bits != table_bits then replicate to fill the remaining slots. */
224 while (total_size != table_size) {
225 memcpy(&table[table_size], &table[0],
226 (size_t)table_size * sizeof(table[0]));
227 table_size <<= 1;
228 }
229
230 /* Fill in 2nd level tables and add pointers to root table. */
231 key_step = BROTLI_REVERSE_BITS_LOWEST((uint64_t)1 << (8 - 1 + 0)) >> (root_bits - 1);
232 sub_key = (BROTLI_REVERSE_BITS_LOWEST((uint64_t)1 << (8 - 1 + 0)) << 1);
233 sub_key_step = BROTLI_REVERSE_BITS_LOWEST((uint64_t)1 << (8 - 1 + 0));
234 for (len = root_bits + 1, step = 2; len <= max_length; ++len) {
235 symbol = len - (BROTLI_HUFFMAN_MAX_CODE_LENGTH15 + 1);
236 for (; count[len] != 0; --count[len]) {
237 if (sub_key == (BROTLI_REVERSE_BITS_LOWEST((uint64_t)1 << (8 - 1 + 0)) << 1U)) {
238 table += table_size;
239 table_bits = NextTableBitSize(count, len, root_bits);
240 table_size = 1 << table_bits;
241 total_size += table_size;
242 sub_key = BrotliReverseBits(key);
243 key += key_step;
244 root_table[sub_key] = ConstructHuffmanCode(
245 (uint8_t)(table_bits + root_bits),
246 (uint16_t)(((size_t)(table - root_table)) - sub_key));
247 sub_key = 0;
248 }
249 symbol = symbol_lists[symbol];
250 code = ConstructHuffmanCode((uint8_t)(len - root_bits), (uint16_t)symbol);
251 ReplicateValue(
252 &table[BrotliReverseBits(sub_key)], step, table_size, code);
253 sub_key += sub_key_step;
254 }
255 step <<= 1;
256 sub_key_step >>= 1;
257 }
258 return (uint32_t)total_size;
259}
260
261uint32_t BrotliBuildSimpleHuffmanTable(HuffmanCode* table,
262 int root_bits,
263 uint16_t* val,
264 uint32_t num_symbols) {
265 uint32_t table_size = 1;
266 const uint32_t goal_size = 1U << root_bits;
267 switch (num_symbols) {
268 case 0:
269 table[0] = ConstructHuffmanCode(0, val[0]);
270 break;
271 case 1:
272 if (val[1] > val[0]) {
273 table[0] = ConstructHuffmanCode(1, val[0]);
274 table[1] = ConstructHuffmanCode(1, val[1]);
275 } else {
276 table[0] = ConstructHuffmanCode(1, val[1]);
277 table[1] = ConstructHuffmanCode(1, val[0]);
278 }
279 table_size = 2;
280 break;
281 case 2:
282 table[0] = ConstructHuffmanCode(1, val[0]);
283 table[2] = ConstructHuffmanCode(1, val[0]);
284 if (val[2] > val[1]) {
285 table[1] = ConstructHuffmanCode(2, val[1]);
286 table[3] = ConstructHuffmanCode(2, val[2]);
287 } else {
288 table[1] = ConstructHuffmanCode(2, val[2]);
289 table[3] = ConstructHuffmanCode(2, val[1]);
290 }
291 table_size = 4;
292 break;
293 case 3: {
294 int i, k;
295 for (i = 0; i < 3; ++i) {
296 for (k = i + 1; k < 4; ++k) {
297 if (val[k] < val[i]) {
298 uint16_t t = val[k];
299 val[k] = val[i];
300 val[i] = t;
301 }
302 }
303 }
304 table[0] = ConstructHuffmanCode(2, val[0]);
305 table[2] = ConstructHuffmanCode(2, val[1]);
306 table[1] = ConstructHuffmanCode(2, val[2]);
307 table[3] = ConstructHuffmanCode(2, val[3]);
308 table_size = 4;
309 break;
310 }
311 case 4: {
312 if (val[3] < val[2]) {
313 uint16_t t = val[3];
314 val[3] = val[2];
315 val[2] = t;
316 }
317 table[0] = ConstructHuffmanCode(1, val[0]);
318 table[1] = ConstructHuffmanCode(2, val[1]);
319 table[2] = ConstructHuffmanCode(1, val[0]);
320 table[3] = ConstructHuffmanCode(3, val[2]);
321 table[4] = ConstructHuffmanCode(1, val[0]);
322 table[5] = ConstructHuffmanCode(2, val[1]);
323 table[6] = ConstructHuffmanCode(1, val[0]);
324 table[7] = ConstructHuffmanCode(3, val[3]);
325 table_size = 8;
326 break;
327 }
328 }
329 while (table_size != goal_size) {
330 memcpy(&table[table_size], &table[0],
331 (size_t)table_size * sizeof(table[0]));
332 table_size <<= 1;
333 }
334 return goal_size;
335}
336
337#if defined(__cplusplus) || defined(c_plusplus)
338} /* extern "C" */
339#endif