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-rw-r--r--lib/zlib_inflate/infcodes.c202
1 files changed, 202 insertions, 0 deletions
diff --git a/lib/zlib_inflate/infcodes.c b/lib/zlib_inflate/infcodes.c
new file mode 100644
index 000000000000..07cd7591cbb7
--- /dev/null
+++ b/lib/zlib_inflate/infcodes.c
@@ -0,0 +1,202 @@
+/* infcodes.c -- process literals and length/distance pairs
+ * Copyright (C) 1995-1998 Mark Adler
+ * For conditions of distribution and use, see copyright notice in zlib.h
+ */
+
+#include <linux/zutil.h>
+#include "inftrees.h"
+#include "infblock.h"
+#include "infcodes.h"
+#include "infutil.h"
+#include "inffast.h"
+
+/* simplify the use of the inflate_huft type with some defines */
+#define exop word.what.Exop
+#define bits word.what.Bits
+
+inflate_codes_statef *zlib_inflate_codes_new(
+ uInt bl,
+ uInt bd,
+ inflate_huft *tl,
+ inflate_huft *td, /* need separate declaration for Borland C++ */
+ z_streamp z
+)
+{
+ inflate_codes_statef *c;
+
+ c = &WS(z)->working_state;
+ {
+ c->mode = START;
+ c->lbits = (Byte)bl;
+ c->dbits = (Byte)bd;
+ c->ltree = tl;
+ c->dtree = td;
+ }
+ return c;
+}
+
+
+int zlib_inflate_codes(
+ inflate_blocks_statef *s,
+ z_streamp z,
+ int r
+)
+{
+ uInt j; /* temporary storage */
+ inflate_huft *t; /* temporary pointer */
+ uInt e; /* extra bits or operation */
+ uLong b; /* bit buffer */
+ uInt k; /* bits in bit buffer */
+ Byte *p; /* input data pointer */
+ uInt n; /* bytes available there */
+ Byte *q; /* output window write pointer */
+ uInt m; /* bytes to end of window or read pointer */
+ Byte *f; /* pointer to copy strings from */
+ inflate_codes_statef *c = s->sub.decode.codes; /* codes state */
+
+ /* copy input/output information to locals (UPDATE macro restores) */
+ LOAD
+
+ /* process input and output based on current state */
+ while (1) switch (c->mode)
+ { /* waiting for "i:"=input, "o:"=output, "x:"=nothing */
+ case START: /* x: set up for LEN */
+#ifndef SLOW
+ if (m >= 258 && n >= 10)
+ {
+ UPDATE
+ r = zlib_inflate_fast(c->lbits, c->dbits, c->ltree, c->dtree, s, z);
+ LOAD
+ if (r != Z_OK)
+ {
+ c->mode = r == Z_STREAM_END ? WASH : BADCODE;
+ break;
+ }
+ }
+#endif /* !SLOW */
+ c->sub.code.need = c->lbits;
+ c->sub.code.tree = c->ltree;
+ c->mode = LEN;
+ case LEN: /* i: get length/literal/eob next */
+ j = c->sub.code.need;
+ NEEDBITS(j)
+ t = c->sub.code.tree + ((uInt)b & zlib_inflate_mask[j]);
+ DUMPBITS(t->bits)
+ e = (uInt)(t->exop);
+ if (e == 0) /* literal */
+ {
+ c->sub.lit = t->base;
+ c->mode = LIT;
+ break;
+ }
+ if (e & 16) /* length */
+ {
+ c->sub.copy.get = e & 15;
+ c->len = t->base;
+ c->mode = LENEXT;
+ break;
+ }
+ if ((e & 64) == 0) /* next table */
+ {
+ c->sub.code.need = e;
+ c->sub.code.tree = t + t->base;
+ break;
+ }
+ if (e & 32) /* end of block */
+ {
+ c->mode = WASH;
+ break;
+ }
+ c->mode = BADCODE; /* invalid code */
+ z->msg = (char*)"invalid literal/length code";
+ r = Z_DATA_ERROR;
+ LEAVE
+ case LENEXT: /* i: getting length extra (have base) */
+ j = c->sub.copy.get;
+ NEEDBITS(j)
+ c->len += (uInt)b & zlib_inflate_mask[j];
+ DUMPBITS(j)
+ c->sub.code.need = c->dbits;
+ c->sub.code.tree = c->dtree;
+ c->mode = DIST;
+ case DIST: /* i: get distance next */
+ j = c->sub.code.need;
+ NEEDBITS(j)
+ t = c->sub.code.tree + ((uInt)b & zlib_inflate_mask[j]);
+ DUMPBITS(t->bits)
+ e = (uInt)(t->exop);
+ if (e & 16) /* distance */
+ {
+ c->sub.copy.get = e & 15;
+ c->sub.copy.dist = t->base;
+ c->mode = DISTEXT;
+ break;
+ }
+ if ((e & 64) == 0) /* next table */
+ {
+ c->sub.code.need = e;
+ c->sub.code.tree = t + t->base;
+ break;
+ }
+ c->mode = BADCODE; /* invalid code */
+ z->msg = (char*)"invalid distance code";
+ r = Z_DATA_ERROR;
+ LEAVE
+ case DISTEXT: /* i: getting distance extra */
+ j = c->sub.copy.get;
+ NEEDBITS(j)
+ c->sub.copy.dist += (uInt)b & zlib_inflate_mask[j];
+ DUMPBITS(j)
+ c->mode = COPY;
+ case COPY: /* o: copying bytes in window, waiting for space */
+ f = q - c->sub.copy.dist;
+ while (f < s->window) /* modulo window size-"while" instead */
+ f += s->end - s->window; /* of "if" handles invalid distances */
+ while (c->len)
+ {
+ NEEDOUT
+ OUTBYTE(*f++)
+ if (f == s->end)
+ f = s->window;
+ c->len--;
+ }
+ c->mode = START;
+ break;
+ case LIT: /* o: got literal, waiting for output space */
+ NEEDOUT
+ OUTBYTE(c->sub.lit)
+ c->mode = START;
+ break;
+ case WASH: /* o: got eob, possibly more output */
+ if (k > 7) /* return unused byte, if any */
+ {
+ k -= 8;
+ n++;
+ p--; /* can always return one */
+ }
+ FLUSH
+ if (s->read != s->write)
+ LEAVE
+ c->mode = END;
+ case END:
+ r = Z_STREAM_END;
+ LEAVE
+ case BADCODE: /* x: got error */
+ r = Z_DATA_ERROR;
+ LEAVE
+ default:
+ r = Z_STREAM_ERROR;
+ LEAVE
+ }
+#ifdef NEED_DUMMY_RETURN
+ return Z_STREAM_ERROR; /* Some dumb compilers complain without this */
+#endif
+}
+
+
+void zlib_inflate_codes_free(
+ inflate_codes_statef *c,
+ z_streamp z
+)
+{
+}