libkern/zlib/inflate.c

28 /* inflate.c -- zlib decompression
37  * - First version -- complete rewrite of inflate to simplify code, avoid
40  *   improve code readability and style over the previous zlib inflate code
51  * - Correct filename to inffixed.h for fixed tables in inflate.c
52  * - Make hbuf[] unsigned char to match parameter type in inflate.c
54  *   to avoid negation problem on Alphas (64 bit) in inflate.c
64  * - Make MATCH copy in inflate() much faster for when inflate_fast() not used
66  *   buffer and bit count in inflate()--for speed when inflate_fast() not used
70  * - Move a comment on output buffer sizes from inffast.c to inflate.c
80  *   source file infback.c to provide a call-back interface to inflate for
105  * - Check next_in and next_out for Z_NULL on entry to inflate()
112 #include "inflate.h"
151     Tracev((stderr, "inflate: reset\n"));
194     Tracev((stderr, "inflate: allocated\n"));
342    inflate call, but the end of the deflate stream has not been reached yet.
346    Providing output buffers larger than 32K to inflate() should provide a speed
348    upon return from inflate(), and since all distances after the first 32K of
402 /* Macros for inflate(): */
431 /* Load registers with state in inflate() for speed */
442 /* Restore state from registers in inflate() */
460 /* Get a byte of input into the bit accumulator, or return from inflate()
471    not enough available input to do that, then return from inflate(). */
502    inflate() uses a state machine to process as much input data and generate as
517    so when inflate() is called again, the same case is attempted again, and
528    where NEEDBITS(n) either returns from inflate() if there isn't enough
565    during that inflate() call in order to return the proper return code.
570    output to the window for the next call of inflate().
572    In this implementation, the flush parameter of inflate() only affects the
573    return code (per zlib.h).  inflate() always writes as much as possible to
575    documented in zlib.h of Z_SYNC_FLUSH.  Furthermore, inflate() always defers
579    when flush is set to Z_FINISH, inflate() cannot return Z_OK.  Instead it
583 int ZEXPORT inflate(strm, flush)
657             Tracev((stderr, "inflate:   zlib header ok\n"));
815                 Tracev((stderr, "inflate:     stored block%s\n",
821                 Tracev((stderr, "inflate:     fixed codes block%s\n",
826                 Tracev((stderr, "inflate:     dynamic codes block%s\n",
845             Tracev((stderr, "inflate:       stored length %u\n",
863             Tracev((stderr, "inflate:       stored end\n"));
881             Tracev((stderr, "inflate:       table sizes ok\n"));
902             Tracev((stderr, "inflate:       code lengths ok\n"));
977             Tracev((stderr, "inflate:       codes ok\n"));
1005                         "inflate:         literal '%c'\n" :
1006                         "inflate:         literal 0x%02x\n", this.val));
1011                 Tracevv((stderr, "inflate:         end of block\n"));
1028             Tracevv((stderr, "inflate:         length %u\n", state->length));
1073             Tracevv((stderr, "inflate:         distance %u\n", state->offset));
1126                 Tracev((stderr, "inflate:   check matches trailer\n"));
1139                 Tracev((stderr, "inflate:   length matches trailer\n"));
1157        Return from inflate(), updating the total counts and the check value.
1158        If there was no progress during the inflate() call, return a buffer
1160        Note: a memory error from inflate() is non-recoverable.
1194     Tracev((stderr, "inflate: end\n"));
1236     Tracev((stderr, "inflate:   dictionary set\n"));
1325     /* return no joy or set up to restart inflate() on a new block */
1335    Returns true if inflate is currently at the end of a block generated by
1340    inflate is waiting for these length bytes.