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author | peter <peter@FreeBSD.org> | 1996-08-18 17:54:27 +0000 |
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committer | peter <peter@FreeBSD.org> | 1996-08-18 17:54:27 +0000 |
commit | 70c83c0586d07013fa8b7756f44d5ec3839b1db0 (patch) | |
tree | ce8fa1b80a1478f3869ad9324fb5d62892f66e07 /lib/libz/infutil.c | |
download | FreeBSD-src-70c83c0586d07013fa8b7756f44d5ec3839b1db0.zip FreeBSD-src-70c83c0586d07013fa8b7756f44d5ec3839b1db0.tar.gz |
Initial import of zlib-1.0.4
Diffstat (limited to 'lib/libz/infutil.c')
-rw-r--r-- | lib/libz/infutil.c | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/lib/libz/infutil.c b/lib/libz/infutil.c new file mode 100644 index 0000000..eb21199 --- /dev/null +++ b/lib/libz/infutil.c @@ -0,0 +1,87 @@ +/* inflate_util.c -- data and routines common to blocks and codes + * Copyright (C) 1995-1996 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ + +#include "zutil.h" +#include "infblock.h" +#include "inftrees.h" +#include "infcodes.h" +#include "infutil.h" + +struct inflate_codes_state {int dummy;}; /* for buggy compilers */ + +/* And'ing with mask[n] masks the lower n bits */ +uInt inflate_mask[17] = { + 0x0000, + 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff, + 0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff +}; + + +/* copy as much as possible from the sliding window to the output area */ +int inflate_flush(s, z, r) +inflate_blocks_statef *s; +z_streamp z; +int r; +{ + uInt n; + Bytef *p; + Bytef *q; + + /* local copies of source and destination pointers */ + p = z->next_out; + q = s->read; + + /* compute number of bytes to copy as far as end of window */ + n = (uInt)((q <= s->write ? s->write : s->end) - q); + if (n > z->avail_out) n = z->avail_out; + if (n && r == Z_BUF_ERROR) r = Z_OK; + + /* update counters */ + z->avail_out -= n; + z->total_out += n; + + /* update check information */ + if (s->checkfn != Z_NULL) + z->adler = s->check = (*s->checkfn)(s->check, q, n); + + /* copy as far as end of window */ + zmemcpy(p, q, n); + p += n; + q += n; + + /* see if more to copy at beginning of window */ + if (q == s->end) + { + /* wrap pointers */ + q = s->window; + if (s->write == s->end) + s->write = s->window; + + /* compute bytes to copy */ + n = (uInt)(s->write - q); + if (n > z->avail_out) n = z->avail_out; + if (n && r == Z_BUF_ERROR) r = Z_OK; + + /* update counters */ + z->avail_out -= n; + z->total_out += n; + + /* update check information */ + if (s->checkfn != Z_NULL) + z->adler = s->check = (*s->checkfn)(s->check, q, n); + + /* copy */ + zmemcpy(p, q, n); + p += n; + q += n; + } + + /* update pointers */ + z->next_out = p; + s->read = q; + + /* done */ + return r; +} |