dist_code[256 + dist++] = (uch)code;
_dist_code[256 + dist++] = (uch)code;
local void tr_static_init(){    static int static_init_done = 0;    int n;        /* iterates over tree elements */    int bits;     /* bit counter */    int length;   /* length value */    int code;     /* code value */    int dist;     /* distance index */    ush bl_count[MAX_BITS+1];    /* number of codes at each bit length for an optimal tree */    if (static_init_done) return;    /* Initialize the mapping length (0..255) -> length code (0..28) */    length = 0;    for (code = 0; code < LENGTH_CODES-1; code++) {        base_length[code] = length;        for (n = 0; n < (1<<extra_lbits[code]); n++) {            length_code[length++] = (uch)code;        }    }    Assert (length == 256, "tr_static_init: length != 256");    /* Note that the length 255 (match length 258) can be represented     * in two different ways: code 284 + 5 bits or code 285, so we     * overwrite length_code[255] to use the best encoding:     */    length_code[length-1] = (uch)code;    /* Initialize the mapping dist (0..32K) -> dist code (0..29) */    dist = 0;    for (code = 0 ; code < 16; code++) {        base_dist[code] = dist;        for (n = 0; n < (1<<extra_dbits[code]); n++) {            dist_code[dist++] = (uch)code;        }    }    Assert (dist == 256, "tr_static_init: dist != 256");    dist >>= 7; /* from now on, all distances are divided by 128 */    for ( ; code < D_CODES; code++) {        base_dist[code] = dist << 7;        for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {            dist_code[256 + dist++] = (uch)code;        }    }    Assert (dist == 256, "tr_static_init: 256+dist != 512");    /* Construct the codes of the static literal tree */    for (bits = 0; bits <= MAX_BITS; bits++) bl_count[bits] = 0;    n = 0;    while (n <= 143) static_ltree[n++].Len = 8, bl_count[8]++;    while (n <= 255) static_ltree[n++].Len = 9, bl_count[9]++;    while (n <= 279) static_ltree[n++].Len = 7, bl_count[7]++;    while (n <= 287) static_ltree[n++].Len = 8, bl_count[8]++;    /* Codes 286 and 287 do not exist, but we must include them in the     * tree construction to get a canonical Huffman tree (longest code     * all ones)     */    gen_codes((ct_data *)static_ltree, L_CODES+1, bl_count);    /* The static distance tree is trivial: */    for (n = 0; n < D_CODES; n++) {        static_dtree[n].Len = 5;        static_dtree[n].Code = bi_reverse((unsigned)n, 5);    }    static_init_done = 1;}