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Rev | Author | Line No. | Line |
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1896 | serge | 1 | /* infback.c -- inflate using a call-back interface |
3926 | Serge | 2 | * Copyright (C) 1995-2011 Mark Adler |
1896 | serge | 3 | * For conditions of distribution and use, see copyright notice in zlib.h |
4 | */ |
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5 | |||
6 | /* |
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7 | This code is largely copied from inflate.c. Normally either infback.o or |
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8 | inflate.o would be linked into an application--not both. The interface |
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9 | with inffast.c is retained so that optimized assembler-coded versions of |
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10 | inflate_fast() can be used with either inflate.c or infback.c. |
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11 | */ |
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12 | |||
13 | #include "zutil.h" |
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14 | #include "inftrees.h" |
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15 | #include "inflate.h" |
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16 | #include "inffast.h" |
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17 | |||
18 | /* function prototypes */ |
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19 | local void fixedtables OF((struct inflate_state FAR *state)); |
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20 | |||
21 | /* |
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22 | strm provides memory allocation functions in zalloc and zfree, or |
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23 | Z_NULL to use the library memory allocation functions. |
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24 | |||
25 | windowBits is in the range 8..15, and window is a user-supplied |
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26 | window and output buffer that is 2**windowBits bytes. |
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27 | */ |
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28 | int ZEXPORT inflateBackInit_(strm, windowBits, window, version, stream_size) |
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29 | z_streamp strm; |
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30 | int windowBits; |
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31 | unsigned char FAR *window; |
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32 | const char *version; |
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33 | int stream_size; |
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34 | { |
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35 | struct inflate_state FAR *state; |
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36 | |||
37 | if (version == Z_NULL || version[0] != ZLIB_VERSION[0] || |
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38 | stream_size != (int)(sizeof(z_stream))) |
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39 | return Z_VERSION_ERROR; |
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40 | if (strm == Z_NULL || window == Z_NULL || |
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41 | windowBits < 8 || windowBits > 15) |
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42 | return Z_STREAM_ERROR; |
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43 | strm->msg = Z_NULL; /* in case we return an error */ |
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44 | if (strm->zalloc == (alloc_func)0) { |
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3926 | Serge | 45 | #ifdef Z_SOLO |
46 | return Z_STREAM_ERROR; |
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47 | #else |
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1896 | serge | 48 | strm->zalloc = zcalloc; |
49 | strm->opaque = (voidpf)0; |
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3926 | Serge | 50 | #endif |
1896 | serge | 51 | } |
3926 | Serge | 52 | if (strm->zfree == (free_func)0) |
53 | #ifdef Z_SOLO |
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54 | return Z_STREAM_ERROR; |
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55 | #else |
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56 | strm->zfree = zcfree; |
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57 | #endif |
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1896 | serge | 58 | state = (struct inflate_state FAR *)ZALLOC(strm, 1, |
59 | sizeof(struct inflate_state)); |
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60 | if (state == Z_NULL) return Z_MEM_ERROR; |
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61 | Tracev((stderr, "inflate: allocated\n")); |
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62 | strm->state = (struct internal_state FAR *)state; |
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63 | state->dmax = 32768U; |
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64 | state->wbits = windowBits; |
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65 | state->wsize = 1U << windowBits; |
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66 | state->window = window; |
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67 | state->wnext = 0; |
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68 | state->whave = 0; |
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69 | return Z_OK; |
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70 | } |
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71 | |||
72 | /* |
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73 | Return state with length and distance decoding tables and index sizes set to |
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74 | fixed code decoding. Normally this returns fixed tables from inffixed.h. |
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75 | If BUILDFIXED is defined, then instead this routine builds the tables the |
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76 | first time it's called, and returns those tables the first time and |
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77 | thereafter. This reduces the size of the code by about 2K bytes, in |
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78 | exchange for a little execution time. However, BUILDFIXED should not be |
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79 | used for threaded applications, since the rewriting of the tables and virgin |
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80 | may not be thread-safe. |
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81 | */ |
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82 | local void fixedtables(state) |
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83 | struct inflate_state FAR *state; |
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84 | { |
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85 | #ifdef BUILDFIXED |
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86 | static int virgin = 1; |
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87 | static code *lenfix, *distfix; |
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88 | static code fixed[544]; |
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89 | |||
90 | /* build fixed huffman tables if first call (may not be thread safe) */ |
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91 | if (virgin) { |
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92 | unsigned sym, bits; |
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93 | static code *next; |
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94 | |||
95 | /* literal/length table */ |
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96 | sym = 0; |
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97 | while (sym < 144) state->lens[sym++] = 8; |
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98 | while (sym < 256) state->lens[sym++] = 9; |
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99 | while (sym < 280) state->lens[sym++] = 7; |
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100 | while (sym < 288) state->lens[sym++] = 8; |
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101 | next = fixed; |
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102 | lenfix = next; |
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103 | bits = 9; |
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104 | inflate_table(LENS, state->lens, 288, &(next), &(bits), state->work); |
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105 | |||
106 | /* distance table */ |
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107 | sym = 0; |
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108 | while (sym < 32) state->lens[sym++] = 5; |
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109 | distfix = next; |
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110 | bits = 5; |
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111 | inflate_table(DISTS, state->lens, 32, &(next), &(bits), state->work); |
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112 | |||
113 | /* do this just once */ |
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114 | virgin = 0; |
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115 | } |
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116 | #else /* !BUILDFIXED */ |
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117 | # include "inffixed.h" |
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118 | #endif /* BUILDFIXED */ |
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119 | state->lencode = lenfix; |
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120 | state->lenbits = 9; |
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121 | state->distcode = distfix; |
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122 | state->distbits = 5; |
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123 | } |
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124 | |||
125 | /* Macros for inflateBack(): */ |
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126 | |||
127 | /* Load returned state from inflate_fast() */ |
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128 | #define LOAD() \ |
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129 | do { \ |
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130 | put = strm->next_out; \ |
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131 | left = strm->avail_out; \ |
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132 | next = strm->next_in; \ |
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133 | have = strm->avail_in; \ |
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134 | hold = state->hold; \ |
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135 | bits = state->bits; \ |
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136 | } while (0) |
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137 | |||
138 | /* Set state from registers for inflate_fast() */ |
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139 | #define RESTORE() \ |
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140 | do { \ |
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141 | strm->next_out = put; \ |
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142 | strm->avail_out = left; \ |
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143 | strm->next_in = next; \ |
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144 | strm->avail_in = have; \ |
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145 | state->hold = hold; \ |
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146 | state->bits = bits; \ |
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147 | } while (0) |
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148 | |||
149 | /* Clear the input bit accumulator */ |
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150 | #define INITBITS() \ |
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151 | do { \ |
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152 | hold = 0; \ |
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153 | bits = 0; \ |
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154 | } while (0) |
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155 | |||
156 | /* Assure that some input is available. If input is requested, but denied, |
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157 | then return a Z_BUF_ERROR from inflateBack(). */ |
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158 | #define PULL() \ |
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159 | do { \ |
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160 | if (have == 0) { \ |
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161 | have = in(in_desc, &next); \ |
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162 | if (have == 0) { \ |
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163 | next = Z_NULL; \ |
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164 | ret = Z_BUF_ERROR; \ |
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165 | goto inf_leave; \ |
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166 | } \ |
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167 | } \ |
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168 | } while (0) |
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169 | |||
170 | /* Get a byte of input into the bit accumulator, or return from inflateBack() |
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171 | with an error if there is no input available. */ |
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172 | #define PULLBYTE() \ |
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173 | do { \ |
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174 | PULL(); \ |
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175 | have--; \ |
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176 | hold += (unsigned long)(*next++) << bits; \ |
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177 | bits += 8; \ |
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178 | } while (0) |
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179 | |||
180 | /* Assure that there are at least n bits in the bit accumulator. If there is |
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181 | not enough available input to do that, then return from inflateBack() with |
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182 | an error. */ |
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183 | #define NEEDBITS(n) \ |
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184 | do { \ |
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185 | while (bits < (unsigned)(n)) \ |
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186 | PULLBYTE(); \ |
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187 | } while (0) |
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188 | |||
189 | /* Return the low n bits of the bit accumulator (n < 16) */ |
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190 | #define BITS(n) \ |
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191 | ((unsigned)hold & ((1U << (n)) - 1)) |
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192 | |||
193 | /* Remove n bits from the bit accumulator */ |
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194 | #define DROPBITS(n) \ |
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195 | do { \ |
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196 | hold >>= (n); \ |
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197 | bits -= (unsigned)(n); \ |
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198 | } while (0) |
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199 | |||
200 | /* Remove zero to seven bits as needed to go to a byte boundary */ |
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201 | #define BYTEBITS() \ |
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202 | do { \ |
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203 | hold >>= bits & 7; \ |
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204 | bits -= bits & 7; \ |
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205 | } while (0) |
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206 | |||
207 | /* Assure that some output space is available, by writing out the window |
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208 | if it's full. If the write fails, return from inflateBack() with a |
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209 | Z_BUF_ERROR. */ |
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210 | #define ROOM() \ |
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211 | do { \ |
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212 | if (left == 0) { \ |
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213 | put = state->window; \ |
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214 | left = state->wsize; \ |
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215 | state->whave = left; \ |
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216 | if (out(out_desc, put, left)) { \ |
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217 | ret = Z_BUF_ERROR; \ |
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218 | goto inf_leave; \ |
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219 | } \ |
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220 | } \ |
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221 | } while (0) |
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222 | |||
223 | /* |
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224 | strm provides the memory allocation functions and window buffer on input, |
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225 | and provides information on the unused input on return. For Z_DATA_ERROR |
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226 | returns, strm will also provide an error message. |
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227 | |||
228 | in() and out() are the call-back input and output functions. When |
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229 | inflateBack() needs more input, it calls in(). When inflateBack() has |
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230 | filled the window with output, or when it completes with data in the |
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231 | window, it calls out() to write out the data. The application must not |
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232 | change the provided input until in() is called again or inflateBack() |
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233 | returns. The application must not change the window/output buffer until |
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234 | inflateBack() returns. |
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235 | |||
236 | in() and out() are called with a descriptor parameter provided in the |
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237 | inflateBack() call. This parameter can be a structure that provides the |
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238 | information required to do the read or write, as well as accumulated |
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239 | information on the input and output such as totals and check values. |
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240 | |||
241 | in() should return zero on failure. out() should return non-zero on |
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242 | failure. If either in() or out() fails, than inflateBack() returns a |
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243 | Z_BUF_ERROR. strm->next_in can be checked for Z_NULL to see whether it |
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244 | was in() or out() that caused in the error. Otherwise, inflateBack() |
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245 | returns Z_STREAM_END on success, Z_DATA_ERROR for an deflate format |
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246 | error, or Z_MEM_ERROR if it could not allocate memory for the state. |
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247 | inflateBack() can also return Z_STREAM_ERROR if the input parameters |
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248 | are not correct, i.e. strm is Z_NULL or the state was not initialized. |
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249 | */ |
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250 | int ZEXPORT inflateBack(strm, in, in_desc, out, out_desc) |
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251 | z_streamp strm; |
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252 | in_func in; |
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253 | void FAR *in_desc; |
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254 | out_func out; |
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255 | void FAR *out_desc; |
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256 | { |
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257 | struct inflate_state FAR *state; |
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3926 | Serge | 258 | z_const unsigned char FAR *next; /* next input */ |
1896 | serge | 259 | unsigned char FAR *put; /* next output */ |
260 | unsigned have, left; /* available input and output */ |
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261 | unsigned long hold; /* bit buffer */ |
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262 | unsigned bits; /* bits in bit buffer */ |
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263 | unsigned copy; /* number of stored or match bytes to copy */ |
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264 | unsigned char FAR *from; /* where to copy match bytes from */ |
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265 | code here; /* current decoding table entry */ |
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266 | code last; /* parent table entry */ |
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267 | unsigned len; /* length to copy for repeats, bits to drop */ |
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268 | int ret; /* return code */ |
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269 | static const unsigned short order[19] = /* permutation of code lengths */ |
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270 | {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; |
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271 | |||
272 | /* Check that the strm exists and that the state was initialized */ |
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273 | if (strm == Z_NULL || strm->state == Z_NULL) |
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274 | return Z_STREAM_ERROR; |
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275 | state = (struct inflate_state FAR *)strm->state; |
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276 | |||
277 | /* Reset the state */ |
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278 | strm->msg = Z_NULL; |
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279 | state->mode = TYPE; |
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280 | state->last = 0; |
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281 | state->whave = 0; |
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282 | next = strm->next_in; |
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283 | have = next != Z_NULL ? strm->avail_in : 0; |
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284 | hold = 0; |
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285 | bits = 0; |
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286 | put = state->window; |
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287 | left = state->wsize; |
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288 | |||
289 | /* Inflate until end of block marked as last */ |
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290 | for (;;) |
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291 | switch (state->mode) { |
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292 | case TYPE: |
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293 | /* determine and dispatch block type */ |
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294 | if (state->last) { |
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295 | BYTEBITS(); |
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296 | state->mode = DONE; |
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297 | break; |
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298 | } |
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299 | NEEDBITS(3); |
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300 | state->last = BITS(1); |
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301 | DROPBITS(1); |
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302 | switch (BITS(2)) { |
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303 | case 0: /* stored block */ |
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304 | Tracev((stderr, "inflate: stored block%s\n", |
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305 | state->last ? " (last)" : "")); |
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306 | state->mode = STORED; |
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307 | break; |
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308 | case 1: /* fixed block */ |
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309 | fixedtables(state); |
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310 | Tracev((stderr, "inflate: fixed codes block%s\n", |
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311 | state->last ? " (last)" : "")); |
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312 | state->mode = LEN; /* decode codes */ |
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313 | break; |
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314 | case 2: /* dynamic block */ |
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315 | Tracev((stderr, "inflate: dynamic codes block%s\n", |
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316 | state->last ? " (last)" : "")); |
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317 | state->mode = TABLE; |
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318 | break; |
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319 | case 3: |
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320 | strm->msg = (char *)"invalid block type"; |
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321 | state->mode = BAD; |
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322 | } |
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323 | DROPBITS(2); |
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324 | break; |
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325 | |||
326 | case STORED: |
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327 | /* get and verify stored block length */ |
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328 | BYTEBITS(); /* go to byte boundary */ |
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329 | NEEDBITS(32); |
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330 | if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) { |
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331 | strm->msg = (char *)"invalid stored block lengths"; |
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332 | state->mode = BAD; |
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333 | break; |
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334 | } |
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335 | state->length = (unsigned)hold & 0xffff; |
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336 | Tracev((stderr, "inflate: stored length %u\n", |
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337 | state->length)); |
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338 | INITBITS(); |
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339 | |||
340 | /* copy stored block from input to output */ |
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341 | while (state->length != 0) { |
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342 | copy = state->length; |
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343 | PULL(); |
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344 | ROOM(); |
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345 | if (copy > have) copy = have; |
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346 | if (copy > left) copy = left; |
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347 | zmemcpy(put, next, copy); |
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348 | have -= copy; |
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349 | next += copy; |
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350 | left -= copy; |
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351 | put += copy; |
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352 | state->length -= copy; |
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353 | } |
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354 | Tracev((stderr, "inflate: stored end\n")); |
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355 | state->mode = TYPE; |
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356 | break; |
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357 | |||
358 | case TABLE: |
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359 | /* get dynamic table entries descriptor */ |
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360 | NEEDBITS(14); |
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361 | state->nlen = BITS(5) + 257; |
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362 | DROPBITS(5); |
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363 | state->ndist = BITS(5) + 1; |
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364 | DROPBITS(5); |
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365 | state->ncode = BITS(4) + 4; |
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366 | DROPBITS(4); |
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367 | #ifndef PKZIP_BUG_WORKAROUND |
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368 | if (state->nlen > 286 || state->ndist > 30) { |
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369 | strm->msg = (char *)"too many length or distance symbols"; |
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370 | state->mode = BAD; |
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371 | break; |
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372 | } |
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373 | #endif |
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374 | Tracev((stderr, "inflate: table sizes ok\n")); |
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375 | |||
376 | /* get code length code lengths (not a typo) */ |
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377 | state->have = 0; |
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378 | while (state->have < state->ncode) { |
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379 | NEEDBITS(3); |
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380 | state->lens[order[state->have++]] = (unsigned short)BITS(3); |
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381 | DROPBITS(3); |
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382 | } |
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383 | while (state->have < 19) |
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384 | state->lens[order[state->have++]] = 0; |
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385 | state->next = state->codes; |
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386 | state->lencode = (code const FAR *)(state->next); |
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387 | state->lenbits = 7; |
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388 | ret = inflate_table(CODES, state->lens, 19, &(state->next), |
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389 | &(state->lenbits), state->work); |
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390 | if (ret) { |
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391 | strm->msg = (char *)"invalid code lengths set"; |
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392 | state->mode = BAD; |
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393 | break; |
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394 | } |
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395 | Tracev((stderr, "inflate: code lengths ok\n")); |
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396 | |||
397 | /* get length and distance code code lengths */ |
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398 | state->have = 0; |
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399 | while (state->have < state->nlen + state->ndist) { |
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400 | for (;;) { |
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401 | here = state->lencode[BITS(state->lenbits)]; |
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402 | if ((unsigned)(here.bits) <= bits) break; |
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403 | PULLBYTE(); |
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404 | } |
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405 | if (here.val < 16) { |
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406 | DROPBITS(here.bits); |
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407 | state->lens[state->have++] = here.val; |
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408 | } |
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409 | else { |
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410 | if (here.val == 16) { |
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411 | NEEDBITS(here.bits + 2); |
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412 | DROPBITS(here.bits); |
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413 | if (state->have == 0) { |
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414 | strm->msg = (char *)"invalid bit length repeat"; |
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415 | state->mode = BAD; |
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416 | break; |
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417 | } |
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418 | len = (unsigned)(state->lens[state->have - 1]); |
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419 | copy = 3 + BITS(2); |
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420 | DROPBITS(2); |
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421 | } |
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422 | else if (here.val == 17) { |
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423 | NEEDBITS(here.bits + 3); |
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424 | DROPBITS(here.bits); |
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425 | len = 0; |
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426 | copy = 3 + BITS(3); |
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427 | DROPBITS(3); |
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428 | } |
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429 | else { |
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430 | NEEDBITS(here.bits + 7); |
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431 | DROPBITS(here.bits); |
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432 | len = 0; |
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433 | copy = 11 + BITS(7); |
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434 | DROPBITS(7); |
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435 | } |
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436 | if (state->have + copy > state->nlen + state->ndist) { |
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437 | strm->msg = (char *)"invalid bit length repeat"; |
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438 | state->mode = BAD; |
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439 | break; |
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440 | } |
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441 | while (copy--) |
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442 | state->lens[state->have++] = (unsigned short)len; |
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443 | } |
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444 | } |
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445 | |||
446 | /* handle error breaks in while */ |
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447 | if (state->mode == BAD) break; |
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448 | |||
449 | /* check for end-of-block code (better have one) */ |
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450 | if (state->lens[256] == 0) { |
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451 | strm->msg = (char *)"invalid code -- missing end-of-block"; |
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452 | state->mode = BAD; |
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453 | break; |
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454 | } |
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455 | |||
456 | /* build code tables -- note: do not change the lenbits or distbits |
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457 | values here (9 and 6) without reading the comments in inftrees.h |
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458 | concerning the ENOUGH constants, which depend on those values */ |
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459 | state->next = state->codes; |
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460 | state->lencode = (code const FAR *)(state->next); |
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461 | state->lenbits = 9; |
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462 | ret = inflate_table(LENS, state->lens, state->nlen, &(state->next), |
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463 | &(state->lenbits), state->work); |
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464 | if (ret) { |
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465 | strm->msg = (char *)"invalid literal/lengths set"; |
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466 | state->mode = BAD; |
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467 | break; |
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468 | } |
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469 | state->distcode = (code const FAR *)(state->next); |
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470 | state->distbits = 6; |
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471 | ret = inflate_table(DISTS, state->lens + state->nlen, state->ndist, |
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472 | &(state->next), &(state->distbits), state->work); |
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473 | if (ret) { |
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474 | strm->msg = (char *)"invalid distances set"; |
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475 | state->mode = BAD; |
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476 | break; |
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477 | } |
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478 | Tracev((stderr, "inflate: codes ok\n")); |
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479 | state->mode = LEN; |
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480 | |||
481 | case LEN: |
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482 | /* use inflate_fast() if we have enough input and output */ |
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483 | if (have >= 6 && left >= 258) { |
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484 | RESTORE(); |
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485 | if (state->whave < state->wsize) |
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486 | state->whave = state->wsize - left; |
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487 | inflate_fast(strm, state->wsize); |
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488 | LOAD(); |
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489 | break; |
||
490 | } |
||
491 | |||
492 | /* get a literal, length, or end-of-block code */ |
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493 | for (;;) { |
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494 | here = state->lencode[BITS(state->lenbits)]; |
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495 | if ((unsigned)(here.bits) <= bits) break; |
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496 | PULLBYTE(); |
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497 | } |
||
498 | if (here.op && (here.op & 0xf0) == 0) { |
||
499 | last = here; |
||
500 | for (;;) { |
||
501 | here = state->lencode[last.val + |
||
502 | (BITS(last.bits + last.op) >> last.bits)]; |
||
503 | if ((unsigned)(last.bits + here.bits) <= bits) break; |
||
504 | PULLBYTE(); |
||
505 | } |
||
506 | DROPBITS(last.bits); |
||
507 | } |
||
508 | DROPBITS(here.bits); |
||
509 | state->length = (unsigned)here.val; |
||
510 | |||
511 | /* process literal */ |
||
512 | if (here.op == 0) { |
||
513 | Tracevv((stderr, here.val >= 0x20 && here.val < 0x7f ? |
||
514 | "inflate: literal '%c'\n" : |
||
515 | "inflate: literal 0x%02x\n", here.val)); |
||
516 | ROOM(); |
||
517 | *put++ = (unsigned char)(state->length); |
||
518 | left--; |
||
519 | state->mode = LEN; |
||
520 | break; |
||
521 | } |
||
522 | |||
523 | /* process end of block */ |
||
524 | if (here.op & 32) { |
||
525 | Tracevv((stderr, "inflate: end of block\n")); |
||
526 | state->mode = TYPE; |
||
527 | break; |
||
528 | } |
||
529 | |||
530 | /* invalid code */ |
||
531 | if (here.op & 64) { |
||
532 | strm->msg = (char *)"invalid literal/length code"; |
||
533 | state->mode = BAD; |
||
534 | break; |
||
535 | } |
||
536 | |||
537 | /* length code -- get extra bits, if any */ |
||
538 | state->extra = (unsigned)(here.op) & 15; |
||
539 | if (state->extra != 0) { |
||
540 | NEEDBITS(state->extra); |
||
541 | state->length += BITS(state->extra); |
||
542 | DROPBITS(state->extra); |
||
543 | } |
||
544 | Tracevv((stderr, "inflate: length %u\n", state->length)); |
||
545 | |||
546 | /* get distance code */ |
||
547 | for (;;) { |
||
548 | here = state->distcode[BITS(state->distbits)]; |
||
549 | if ((unsigned)(here.bits) <= bits) break; |
||
550 | PULLBYTE(); |
||
551 | } |
||
552 | if ((here.op & 0xf0) == 0) { |
||
553 | last = here; |
||
554 | for (;;) { |
||
555 | here = state->distcode[last.val + |
||
556 | (BITS(last.bits + last.op) >> last.bits)]; |
||
557 | if ((unsigned)(last.bits + here.bits) <= bits) break; |
||
558 | PULLBYTE(); |
||
559 | } |
||
560 | DROPBITS(last.bits); |
||
561 | } |
||
562 | DROPBITS(here.bits); |
||
563 | if (here.op & 64) { |
||
564 | strm->msg = (char *)"invalid distance code"; |
||
565 | state->mode = BAD; |
||
566 | break; |
||
567 | } |
||
568 | state->offset = (unsigned)here.val; |
||
569 | |||
570 | /* get distance extra bits, if any */ |
||
571 | state->extra = (unsigned)(here.op) & 15; |
||
572 | if (state->extra != 0) { |
||
573 | NEEDBITS(state->extra); |
||
574 | state->offset += BITS(state->extra); |
||
575 | DROPBITS(state->extra); |
||
576 | } |
||
577 | if (state->offset > state->wsize - (state->whave < state->wsize ? |
||
578 | left : 0)) { |
||
579 | strm->msg = (char *)"invalid distance too far back"; |
||
580 | state->mode = BAD; |
||
581 | break; |
||
582 | } |
||
583 | Tracevv((stderr, "inflate: distance %u\n", state->offset)); |
||
584 | |||
585 | /* copy match from window to output */ |
||
586 | do { |
||
587 | ROOM(); |
||
588 | copy = state->wsize - state->offset; |
||
589 | if (copy < left) { |
||
590 | from = put + copy; |
||
591 | copy = left - copy; |
||
592 | } |
||
593 | else { |
||
594 | from = put - state->offset; |
||
595 | copy = left; |
||
596 | } |
||
597 | if (copy > state->length) copy = state->length; |
||
598 | state->length -= copy; |
||
599 | left -= copy; |
||
600 | do { |
||
601 | *put++ = *from++; |
||
602 | } while (--copy); |
||
603 | } while (state->length != 0); |
||
604 | break; |
||
605 | |||
606 | case DONE: |
||
607 | /* inflate stream terminated properly -- write leftover output */ |
||
608 | ret = Z_STREAM_END; |
||
609 | if (left < state->wsize) { |
||
610 | if (out(out_desc, state->window, state->wsize - left)) |
||
611 | ret = Z_BUF_ERROR; |
||
612 | } |
||
613 | goto inf_leave; |
||
614 | |||
615 | case BAD: |
||
616 | ret = Z_DATA_ERROR; |
||
617 | goto inf_leave; |
||
618 | |||
619 | default: /* can't happen, but makes compilers happy */ |
||
620 | ret = Z_STREAM_ERROR; |
||
621 | goto inf_leave; |
||
622 | } |
||
623 | |||
624 | /* Return unused input */ |
||
625 | inf_leave: |
||
626 | strm->next_in = next; |
||
627 | strm->avail_in = have; |
||
628 | return ret; |
||
629 | } |
||
630 | |||
631 | int ZEXPORT inflateBackEnd(strm) |
||
632 | z_streamp strm; |
||
633 | { |
||
634 | if (strm == Z_NULL || strm->state == Z_NULL || strm->zfree == (free_func)0) |
||
635 | return Z_STREAM_ERROR; |
||
636 | ZFREE(strm, strm->state); |
||
637 | strm->state = Z_NULL; |
||
638 | Tracev((stderr, "inflate: end\n")); |
||
639 | return Z_OK; |
||
640 | }>>>=>=>>=>=>>>=>>>>><>>>><>>>>>>><>> |