version 1.5, 1997/07/06 20:23:00 |
version 1.6, 1999/03/04 15:04:45 |
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#define BITS 16 /* Default bits. */ |
#define BITS 16 /* Default bits. */ |
#define HSIZE 69001 /* 95% occupancy */ |
#define HSIZE 69001 /* 95% occupancy */ |
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#define ZBUFSIZ 8192 /* I/O buffer size */ |
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/* A code_int must be able to hold 2**BITS values of type int, and also -1. */ |
/* A code_int must be able to hold 2**BITS values of type int, and also -1. */ |
typedef long code_int; |
typedef long code_int; |
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int zs_clear_flg; |
int zs_clear_flg; |
long zs_ratio; |
long zs_ratio; |
count_int zs_checkpoint; |
count_int zs_checkpoint; |
int zs_offset; |
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long zs_in_count; /* Length of input. */ |
long zs_in_count; /* Length of input. */ |
long zs_bytes_out; /* Length of compressed output. */ |
long zs_bytes_out; /* Length of compressed output. */ |
long zs_out_count; /* # of codes output (for debugging).*/ |
long zs_out_count; /* # of codes output (for debugging).*/ |
u_char zs_buf[BITS]; |
u_char zs_buf[ZBUFSIZ]; /* I/O buffer */ |
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u_char *zs_bp; /* Current I/O window in the zs_buf */ |
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int zs_offset; /* Number of bits in the zs_buf */ |
union { |
union { |
struct { |
struct { |
long zs_fcode; |
long zs_fcode; |
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int zs_hshift; |
int zs_hshift; |
} w; /* Write paramenters */ |
} w; /* Write paramenters */ |
struct { |
struct { |
u_char *zs_stackp; |
u_char *zs_stackp, *zs_ebp; |
int zs_finchar; |
int zs_finchar; |
code_int zs_code, zs_oldcode, zs_incode; |
code_int zs_code, zs_oldcode, zs_incode; |
int zs_roffset, zs_size; |
int zs_size; |
} r; /* Read parameters */ |
} r; /* Read parameters */ |
} u; |
} u; |
}; |
}; |
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#define zs_code u.r.zs_code |
#define zs_code u.r.zs_code |
#define zs_oldcode u.r.zs_oldcode |
#define zs_oldcode u.r.zs_oldcode |
#define zs_incode u.r.zs_incode |
#define zs_incode u.r.zs_incode |
#define zs_roffset u.r.zs_roffset |
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#define zs_size u.r.zs_size |
#define zs_size u.r.zs_size |
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#define zs_ebp u.r.zs_ebp |
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/* |
/* |
* To save much memory, we overlay the table used by compress() with those |
* To save much memory, we overlay the table used by compress() with those |
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u_char tmp; |
u_char tmp; |
int count; |
int count; |
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if (num == 0) |
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return (0); |
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zs = cookie; |
zs = cookie; |
count = num; |
count = num; |
bp = (u_char *)wbp; |
bp = (u_char *)wbp; |
if (zs->zs_state == S_MIDDLE) |
switch (zs->zs_state) { |
goto middle; |
case S_EOF: |
zs->zs_state = S_MIDDLE; |
return 0; |
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case S_START: |
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zs->zs_state = S_MIDDLE; |
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zs->zs_maxmaxcode = 1L << zs->zs_maxbits; |
zs->zs_maxmaxcode = 1L << zs->zs_maxbits; |
if (write(zs->zs_fd, z_magic, sizeof(z_magic)) != sizeof(z_magic)) |
if (write(zs->zs_fd, z_magic, sizeof(z_magic)) != |
return (-1); |
sizeof(z_magic)) |
tmp = (u_char)(zs->zs_maxbits | zs->zs_block_compress); |
return (-1); |
if (write(zs->zs_fd, &tmp, sizeof(tmp)) != sizeof(tmp)) |
tmp = (u_char)(zs->zs_maxbits | zs->zs_block_compress); |
return (-1); |
if (write(zs->zs_fd, &tmp, sizeof(tmp)) != sizeof(tmp)) |
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return (-1); |
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zs->zs_offset = 0; |
zs->zs_bp = zs->zs_buf; |
zs->zs_bytes_out = 3; /* Includes 3-byte header mojo. */ |
zs->zs_offset = 0; |
zs->zs_out_count = 0; |
zs->zs_bytes_out = 3; /* Includes 3-byte header mojo. */ |
zs->zs_clear_flg = 0; |
zs->zs_out_count = 0; |
zs->zs_ratio = 0; |
zs->zs_clear_flg = 0; |
zs->zs_in_count = 1; |
zs->zs_ratio = 0; |
zs->zs_checkpoint = CHECK_GAP; |
zs->zs_in_count = 1; |
zs->zs_maxcode = MAXCODE(zs->zs_n_bits = INIT_BITS); |
zs->zs_checkpoint = CHECK_GAP; |
zs->zs_free_ent = ((zs->zs_block_compress) ? FIRST : 256); |
zs->zs_maxcode = MAXCODE(zs->zs_n_bits = INIT_BITS); |
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zs->zs_free_ent = ((zs->zs_block_compress) ? FIRST : 256); |
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zs->zs_ent = *bp++; |
zs->zs_ent = *bp++; |
--count; |
--count; |
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zs->zs_hshift = 0; |
zs->zs_hshift = 0; |
for (zs->zs_fcode = (long)zs->zs_hsize; zs->zs_fcode < 65536L; |
for (zs->zs_fcode = (long)zs->zs_hsize; zs->zs_fcode < 65536L; |
zs->zs_fcode *= 2L) |
zs->zs_fcode *= 2L) |
zs->zs_hshift++; |
zs->zs_hshift++; |
zs->zs_hshift = 8 - zs->zs_hshift; /* Set hash code range bound. */ |
/* Set hash code range bound. */ |
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zs->zs_hshift = 8 - zs->zs_hshift; |
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zs->zs_hsize_reg = zs->zs_hsize; |
zs->zs_hsize_reg = zs->zs_hsize; |
cl_hash(zs, (count_int)zs->zs_hsize_reg); /* Clear hash table. */ |
/* Clear hash table. */ |
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cl_hash(zs, (count_int)zs->zs_hsize_reg); |
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middle: for (i = 0; count--;) { |
case S_MIDDLE: |
c = *bp++; |
for (i = 0; count-- > 0;) { |
zs->zs_in_count++; |
c = *bp++; |
zs->zs_fcode = (long)(((long)c << zs->zs_maxbits) + |
zs->zs_in_count++; |
zs->zs_ent); |
zs->zs_fcode = (long)(((long)c << zs->zs_maxbits) + |
i = ((c << zs->zs_hshift) ^ zs->zs_ent); /* Xor hashing. */ |
zs->zs_ent); |
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/* Xor hashing. */ |
if (htabof(i) == zs->zs_fcode) { |
i = ((c << zs->zs_hshift) ^ zs->zs_ent); |
zs->zs_ent = codetabof(i); |
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continue; |
if (htabof(i) == zs->zs_fcode) { |
} else if ((long)htabof(i) < 0) /* Empty slot. */ |
zs->zs_ent = codetabof(i); |
goto nomatch; |
continue; |
/* Secondary hash (after G. Knott). */ |
} else if ((long)htabof(i) < 0) /* Empty slot. */ |
disp = zs->zs_hsize_reg - i; |
goto nomatch; |
if (i == 0) |
/* Secondary hash (after G. Knott). */ |
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disp = zs->zs_hsize_reg - i; |
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if (i == 0) |
disp = 1; |
disp = 1; |
probe: if ((i -= disp) < 0) |
probe: if ((i -= disp) < 0) |
i += zs->zs_hsize_reg; |
i += zs->zs_hsize_reg; |
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if (htabof(i) == zs->zs_fcode) { |
if (htabof(i) == zs->zs_fcode) { |
zs->zs_ent = codetabof(i); |
zs->zs_ent = codetabof(i); |
continue; |
continue; |
} |
} |
if ((long)htabof(i) >= 0) |
if ((long)htabof(i) >= 0) |
goto probe; |
goto probe; |
nomatch: if (output(zs, (code_int) zs->zs_ent) == -1) |
nomatch: if (output(zs, (code_int) zs->zs_ent) == -1) |
return (-1); |
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zs->zs_out_count++; |
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zs->zs_ent = c; |
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if (zs->zs_free_ent < zs->zs_maxmaxcode) { |
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/* code -> hashtable */ |
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codetabof(i) = zs->zs_free_ent++; |
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htabof(i) = zs->zs_fcode; |
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} else if ((count_int)zs->zs_in_count >= |
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zs->zs_checkpoint && zs->zs_block_compress) { |
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if (cl_block(zs) == -1) |
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return (-1); |
return (-1); |
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zs->zs_out_count++; |
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zs->zs_ent = c; |
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if (zs->zs_free_ent < zs->zs_maxmaxcode) { |
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/* code -> hashtable */ |
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codetabof(i) = zs->zs_free_ent++; |
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htabof(i) = zs->zs_fcode; |
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} else if ((count_int)zs->zs_in_count >= |
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zs->zs_checkpoint && zs->zs_block_compress) { |
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if (cl_block(zs) == -1) |
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return (-1); |
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} |
} |
} |
} |
} |
return (num); |
return (num); |
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* code in turn. When the buffer fills up empty it and start over. |
* code in turn. When the buffer fills up empty it and start over. |
*/ |
*/ |
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static u_char lmask[9] = |
static const u_char lmask[9] = |
{0xff, 0xfe, 0xfc, 0xf8, 0xf0, 0xe0, 0xc0, 0x80, 0x00}; |
{0xff, 0xfe, 0xfc, 0xf8, 0xf0, 0xe0, 0xc0, 0x80, 0x00}; |
static u_char rmask[9] = |
static const u_char rmask[9] = |
{0x00, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f, 0xff}; |
{0x00, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f, 0xff}; |
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static int |
static int |
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register struct s_zstate *zs; |
register struct s_zstate *zs; |
code_int ocode; |
code_int ocode; |
{ |
{ |
register int bits, r_off; |
register int bits; |
register u_char *bp; |
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r_off = zs->zs_offset; |
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bits = zs->zs_n_bits; |
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bp = zs->zs_buf; |
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if (ocode >= 0) { |
if (ocode >= 0) { |
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register int r_off; |
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register u_char *bp; |
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/* Get to the first byte. */ |
/* Get to the first byte. */ |
bp += (r_off >> 3); |
bp = zs->zs_bp + (zs->zs_offset >> 3); |
r_off &= 7; |
r_off = zs->zs_offset & 7; |
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bits = zs->zs_n_bits; |
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/* |
/* |
* Since ocode is always >= 8 bits, only need to mask the first |
* Since ocode is always >= 8 bits, only need to mask the first |
* hunk on the left. |
* hunk on the left. |
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*bp = ocode; |
*bp = ocode; |
zs->zs_offset += zs->zs_n_bits; |
zs->zs_offset += zs->zs_n_bits; |
if (zs->zs_offset == (zs->zs_n_bits << 3)) { |
if (zs->zs_offset == (zs->zs_n_bits << 3)) { |
bp = zs->zs_buf; |
zs->zs_bp += zs->zs_n_bits; |
bits = zs->zs_n_bits; |
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zs->zs_bytes_out += bits; |
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if (write(zs->zs_fd, bp, bits) != bits) |
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return (-1); |
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bp += bits; |
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bits = 0; |
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zs->zs_offset = 0; |
zs->zs_offset = 0; |
} |
} |
/* |
/* |
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* discover the size increase until after it has read it |
* discover the size increase until after it has read it |
*/ |
*/ |
if (zs->zs_offset > 0) { |
if (zs->zs_offset > 0) { |
if (write(zs->zs_fd, zs->zs_buf, zs->zs_n_bits) |
zs->zs_bp += zs->zs_n_bits; |
!= zs->zs_n_bits) |
zs->zs_offset = 0; |
return (-1); |
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zs->zs_bytes_out += zs->zs_n_bits; |
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} |
} |
zs->zs_offset = 0; |
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if (zs->zs_clear_flg) { |
if (zs->zs_clear_flg) { |
zs->zs_maxcode = |
zs->zs_maxcode = |
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MAXCODE(zs->zs_n_bits); |
MAXCODE(zs->zs_n_bits); |
} |
} |
} |
} |
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if (zs->zs_bp + zs->zs_n_bits > &zs->zs_buf[ZBUFSIZ]) { |
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bits = zs->zs_bp - zs->zs_buf; |
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if (write(zs->zs_fd, zs->zs_buf, bits) != bits) |
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return (-1); |
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zs->zs_bytes_out += bits; |
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if (zs->zs_offset > 0) |
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fprintf (stderr, "zs_offset != 0\n"); |
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zs->zs_bp = zs->zs_buf; |
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} |
} else { |
} else { |
/* At EOF, write the rest of the buffer. */ |
/* At EOF, write the rest of the buffer. */ |
if (zs->zs_offset > 0) { |
if (zs->zs_offset > 0) |
zs->zs_offset = (zs->zs_offset + 7) / 8; |
zs->zs_bp += (zs->zs_offset + 7) / 8; |
if (write(zs->zs_fd, zs->zs_buf, zs->zs_offset) |
if (zs->zs_bp > zs->zs_buf) { |
!= zs->zs_offset) |
bits = zs->zs_bp - zs->zs_buf; |
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if (write(zs->zs_fd, zs->zs_buf, bits) != bits) |
return (-1); |
return (-1); |
zs->zs_bytes_out += zs->zs_offset; |
zs->zs_bytes_out += bits; |
} |
} |
zs->zs_offset = 0; |
zs->zs_offset = 0; |
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zs->zs_bp = zs->zs_buf; |
} |
} |
return (0); |
return (0); |
} |
} |
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switch (zs->zs_state) { |
switch (zs->zs_state) { |
case S_START: |
case S_START: |
zs->zs_state = S_MIDDLE; |
zs->zs_state = S_MIDDLE; |
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zs->zs_bp = zs->zs_buf; |
break; |
break; |
case S_MIDDLE: |
case S_MIDDLE: |
goto middle; |
goto middle; |
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register int r_off, bits; |
register int r_off, bits; |
register u_char *bp; |
register u_char *bp; |
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bp = zs->zs_buf; |
if (zs->zs_clear_flg > 0 || zs->zs_offset >= zs->zs_size || |
if (zs->zs_clear_flg > 0 || zs->zs_roffset >= zs->zs_size || |
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zs->zs_free_ent > zs->zs_maxcode) { |
zs->zs_free_ent > zs->zs_maxcode) { |
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zs->zs_bp += zs->zs_n_bits; |
/* |
/* |
* If the next entry will be too big for the current gcode |
* If the next entry will be too big for the current gcode |
* size, then we must increase the size. This implies reading |
* size, then we must increase the size. This implies reading |
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zs->zs_maxcode = MAXCODE(zs->zs_n_bits = INIT_BITS); |
zs->zs_maxcode = MAXCODE(zs->zs_n_bits = INIT_BITS); |
zs->zs_clear_flg = 0; |
zs->zs_clear_flg = 0; |
} |
} |
zs->zs_size = read(zs->zs_fd, zs->zs_buf, zs->zs_n_bits); |
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if (zs->zs_size <= 0) /* End of file. */ |
/* fill the buffer up to the neck */ |
return (-1); |
if (zs->zs_bp + zs->zs_n_bits > zs->zs_ebp) { |
zs->zs_roffset = 0; |
for (bp = zs->zs_buf; zs->zs_bp < zs->zs_ebp; |
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*bp++ = *zs->zs_bp++); |
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if ((bits = read(zs->zs_fd, bp, ZBUFSIZ - |
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(bp - zs->zs_buf))) < 0) |
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return -1; |
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zs->zs_bp = zs->zs_buf; |
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zs->zs_ebp = bp + bits; |
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} |
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zs->zs_offset = 0; |
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zs->zs_size = MIN(zs->zs_n_bits, zs->zs_ebp - zs->zs_bp); |
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if (zs->zs_size == 0) |
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return -1; |
/* Round size down to integral number of codes. */ |
/* Round size down to integral number of codes. */ |
zs->zs_size = (zs->zs_size << 3) - (zs->zs_n_bits - 1); |
zs->zs_size = (zs->zs_size << 3) - (zs->zs_n_bits - 1); |
} |
} |
r_off = zs->zs_roffset; |
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bp = zs->zs_bp; |
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r_off = zs->zs_offset; |
bits = zs->zs_n_bits; |
bits = zs->zs_n_bits; |
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/* Get to the first byte. */ |
/* Get to the first byte. */ |
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/* High order bits. */ |
/* High order bits. */ |
gcode |= (*bp & rmask[bits]) << r_off; |
gcode |= (*bp & rmask[bits]) << r_off; |
zs->zs_roffset += zs->zs_n_bits; |
zs->zs_offset += zs->zs_n_bits; |
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return (gcode); |
return (gcode); |
} |
} |
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zs->zs_in_count = 1; /* Length of input. */ |
zs->zs_in_count = 1; /* Length of input. */ |
zs->zs_out_count = 0; /* # of codes output (for debugging).*/ |
zs->zs_out_count = 0; /* # of codes output (for debugging).*/ |
zs->zs_state = S_START; |
zs->zs_state = S_START; |
zs->zs_roffset = 0; |
zs->zs_offset = 0; |
zs->zs_size = 0; |
zs->zs_size = 0; |
zs->zs_mode = mode[0]; |
zs->zs_mode = mode[0]; |
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zs->zs_bp = zs->zs_ebp = zs->zs_buf; |
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zs->zs_fd = fd; |
zs->zs_fd = fd; |
return zs; |
return zs; |