Remove builtin copy of zlib

On GNU/Linux, *BSD or MacOS we can simply use the system default
library. The copy was primarily only there for the Windows build.

The build script for Windows has now been adapted to download and
compile a shared library from a tarball.

This removes a huge chunk of code from the git tree as well as
the release tarballs. Additionally it gets rid of iffy things like
removing the Zlib copyright/version strings, so the libsquashfs DLL
doesn't export it.

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

1 files changed, 0 insertions, 323 deletions

diff --git a/lib/zlib/inffast.c b/lib/zlib/inffast.c
deleted file mode 100644
index 1fec7f3..0000000
--- a/lib/zlib/inffast.c
+++ /dev/null
@@ -1,323 +0,0 @@
-/* inffast.c -- fast decoding
- * Copyright (C) 1995-2017 Mark Adler
- * For conditions of distribution and use, see copyright notice in zlib.h
- */
-
-#include "zutil.h"
-#include "inftrees.h"
-#include "inflate.h"
-#include "inffast.h"
-
-#ifdef ASMINF
-#  pragma message("Assembler code may have bugs -- use at your own risk")
-#else
-
-/*
-   Decode literal, length, and distance codes and write out the resulting
-   literal and match bytes until either not enough input or output is
-   available, an end-of-block is encountered, or a data error is encountered.
-   When large enough input and output buffers are supplied to inflate(), for
-   example, a 16K input buffer and a 64K output buffer, more than 95% of the
-   inflate execution time is spent in this routine.
-
-   Entry assumptions:
-
-        state->mode == LEN
-        strm->avail_in >= 6
-        strm->avail_out >= 258
-        start >= strm->avail_out
-        state->bits < 8
-
-   On return, state->mode is one of:
-
-        LEN -- ran out of enough output space or enough available input
-        TYPE -- reached end of block code, inflate() to interpret next block
-        BAD -- error in block data
-
-   Notes:
-
-    - The maximum input bits used by a length/distance pair is 15 bits for the
-      length code, 5 bits for the length extra, 15 bits for the distance code,
-      and 13 bits for the distance extra.  This totals 48 bits, or six bytes.
-      Therefore if strm->avail_in >= 6, then there is enough input to avoid
-      checking for available input while decoding.
-
-    - The maximum bytes that a single length/distance pair can output is 258
-      bytes, which is the maximum length that can be coded.  inflate_fast()
-      requires strm->avail_out >= 258 for each loop to avoid checking for
-      output space.
- */
-void ZLIB_INTERNAL inflate_fast(strm, start)
-z_streamp strm;
-unsigned start;         /* inflate()'s starting value for strm->avail_out */
-{
-    struct inflate_state FAR *state;
-    z_const unsigned char FAR *in;      /* local strm->next_in */
-    z_const unsigned char FAR *last;    /* have enough input while in < last */
-    unsigned char FAR *out;     /* local strm->next_out */
-    unsigned char FAR *beg;     /* inflate()'s initial strm->next_out */
-    unsigned char FAR *end;     /* while out < end, enough space available */
-#ifdef INFLATE_STRICT
-    unsigned dmax;              /* maximum distance from zlib header */
-#endif
-    unsigned wsize;             /* window size or zero if not using window */
-    unsigned whave;             /* valid bytes in the window */
-    unsigned wnext;             /* window write index */
-    unsigned char FAR *window;  /* allocated sliding window, if wsize != 0 */
-    unsigned long hold;         /* local strm->hold */
-    unsigned bits;              /* local strm->bits */
-    code const FAR *lcode;      /* local strm->lencode */
-    code const FAR *dcode;      /* local strm->distcode */
-    unsigned lmask;             /* mask for first level of length codes */
-    unsigned dmask;             /* mask for first level of distance codes */
-    code const *here;           /* retrieved table entry */
-    unsigned op;                /* code bits, operation, extra bits, or */
-                                /*  window position, window bytes to copy */
-    unsigned len;               /* match length, unused bytes */
-    unsigned dist;              /* match distance */
-    unsigned char FAR *from;    /* where to copy match from */
-
-    /* copy state to local variables */
-    state = (struct inflate_state FAR *)strm->state;
-    in = strm->next_in;
-    last = in + (strm->avail_in - 5);
-    out = strm->next_out;
-    beg = out - (start - strm->avail_out);
-    end = out + (strm->avail_out - 257);
-#ifdef INFLATE_STRICT
-    dmax = state->dmax;
-#endif
-    wsize = state->wsize;
-    whave = state->whave;
-    wnext = state->wnext;
-    window = state->window;
-    hold = state->hold;
-    bits = state->bits;
-    lcode = state->lencode;
-    dcode = state->distcode;
-    lmask = (1U << state->lenbits) - 1;
-    dmask = (1U << state->distbits) - 1;
-
-    /* decode literals and length/distances until end-of-block or not enough
-       input data or output space */
-    do {
-        if (bits < 15) {
-            hold += (unsigned long)(*in++) << bits;
-            bits += 8;
-            hold += (unsigned long)(*in++) << bits;
-            bits += 8;
-        }
-        here = lcode + (hold & lmask);
-      dolen:
-        op = (unsigned)(here->bits);
-        hold >>= op;
-        bits -= op;
-        op = (unsigned)(here->op);
-        if (op == 0) {                          /* literal */
-            Tracevv((stderr, here->val >= 0x20 && here->val < 0x7f ?
-                    "inflate:         literal '%c'\n" :
-                    "inflate:         literal 0x%02x\n", here->val));
-            *out++ = (unsigned char)(here->val);
-        }
-        else if (op & 16) {                     /* length base */
-            len = (unsigned)(here->val);
-            op &= 15;                           /* number of extra bits */
-            if (op) {
-                if (bits < op) {
-                    hold += (unsigned long)(*in++) << bits;
-                    bits += 8;
-                }
-                len += (unsigned)hold & ((1U << op) - 1);
-                hold >>= op;
-                bits -= op;
-            }
-            Tracevv((stderr, "inflate:         length %u\n", len));
-            if (bits < 15) {
-                hold += (unsigned long)(*in++) << bits;
-                bits += 8;
-                hold += (unsigned long)(*in++) << bits;
-                bits += 8;
-            }
-            here = dcode + (hold & dmask);
-          dodist:
-            op = (unsigned)(here->bits);
-            hold >>= op;
-            bits -= op;
-            op = (unsigned)(here->op);
-            if (op & 16) {                      /* distance base */
-                dist = (unsigned)(here->val);
-                op &= 15;                       /* number of extra bits */
-                if (bits < op) {
-                    hold += (unsigned long)(*in++) << bits;
-                    bits += 8;
-                    if (bits < op) {
-                        hold += (unsigned long)(*in++) << bits;
-                        bits += 8;
-                    }
-                }
-                dist += (unsigned)hold & ((1U << op) - 1);
-#ifdef INFLATE_STRICT
-                if (dist > dmax) {
-                    strm->msg = (char *)"invalid distance too far back";
-                    state->mode = BAD;
-                    break;
-                }
-#endif
-                hold >>= op;
-                bits -= op;
-                Tracevv((stderr, "inflate:         distance %u\n", dist));
-                op = (unsigned)(out - beg);     /* max distance in output */
-                if (dist > op) {                /* see if copy from window */
-                    op = dist - op;             /* distance back in window */
-                    if (op > whave) {
-                        if (state->sane) {
-                            strm->msg =
-                                (char *)"invalid distance too far back";
-                            state->mode = BAD;
-                            break;
-                        }
-#ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR
-                        if (len <= op - whave) {
-                            do {
-                                *out++ = 0;
-                            } while (--len);
-                            continue;
-                        }
-                        len -= op - whave;
-                        do {
-                            *out++ = 0;
-                        } while (--op > whave);
-                        if (op == 0) {
-                            from = out - dist;
-                            do {
-                                *out++ = *from++;
-                            } while (--len);
-                            continue;
-                        }
-#endif
-                    }
-                    from = window;
-                    if (wnext == 0) {           /* very common case */
-                        from += wsize - op;
-                        if (op < len) {         /* some from window */
-                            len -= op;
-                            do {
-                                *out++ = *from++;
-                            } while (--op);
-                            from = out - dist;  /* rest from output */
-                        }
-                    }
-                    else if (wnext < op) {      /* wrap around window */
-                        from += wsize + wnext - op;
-                        op -= wnext;
-                        if (op < len) {         /* some from end of window */
-                            len -= op;
-                            do {
-                                *out++ = *from++;
-                            } while (--op);
-                            from = window;
-                            if (wnext < len) {  /* some from start of window */
-                                op = wnext;
-                                len -= op;
-                                do {
-                                    *out++ = *from++;
-                                } while (--op);
-                                from = out - dist;      /* rest from output */
-                            }
-                        }
-                    }
-                    else {                      /* contiguous in window */
-                        from += wnext - op;
-                        if (op < len) {         /* some from window */
-                            len -= op;
-                            do {
-                                *out++ = *from++;
-                            } while (--op);
-                            from = out - dist;  /* rest from output */
-                        }
-                    }
-                    while (len > 2) {
-                        *out++ = *from++;
-                        *out++ = *from++;
-                        *out++ = *from++;
-                        len -= 3;
-                    }
-                    if (len) {
-                        *out++ = *from++;
-                        if (len > 1)
-                            *out++ = *from++;
-                    }
-                }
-                else {
-                    from = out - dist;          /* copy direct from output */
-                    do {                        /* minimum length is three */
-                        *out++ = *from++;
-                        *out++ = *from++;
-                        *out++ = *from++;
-                        len -= 3;
-                    } while (len > 2);
-                    if (len) {
-                        *out++ = *from++;
-                        if (len > 1)
-                            *out++ = *from++;
-                    }
-                }
-            }
-            else if ((op & 64) == 0) {          /* 2nd level distance code */
-                here = dcode + here->val + (hold & ((1U << op) - 1));
-                goto dodist;
-            }
-            else {
-                strm->msg = (char *)"invalid distance code";
-                state->mode = BAD;
-                break;
-            }
-        }
-        else if ((op & 64) == 0) {              /* 2nd level length code */
-            here = lcode + here->val + (hold & ((1U << op) - 1));
-            goto dolen;
-        }
-        else if (op & 32) {                     /* end-of-block */
-            Tracevv((stderr, "inflate:         end of block\n"));
-            state->mode = TYPE;
-            break;
-        }
-        else {
-            strm->msg = (char *)"invalid literal/length code";
-            state->mode = BAD;
-            break;
-        }
-    } while (in < last && out < end);
-
-    /* return unused bytes (on entry, bits < 8, so in won't go too far back) */
-    len = bits >> 3;
-    in -= len;
-    bits -= len << 3;
-    hold &= (1U << bits) - 1;
-
-    /* update state and return */
-    strm->next_in = in;
-    strm->next_out = out;
-    strm->avail_in = (unsigned)(in < last ? 5 + (last - in) : 5 - (in - last));
-    strm->avail_out = (unsigned)(out < end ?
-                                 257 + (end - out) : 257 - (out - end));
-    state->hold = hold;
-    state->bits = bits;
-    return;
-}
-
-/*
-   inflate_fast() speedups that turned out slower (on a PowerPC G3 750CXe):
-   - Using bit fields for code structure
-   - Different op definition to avoid & for extra bits (do & for table bits)
-   - Three separate decoding do-loops for direct, window, and wnext == 0
-   - Special case for distance > 1 copies to do overlapped load and store copy
-   - Explicit branch predictions (based on measured branch probabilities)
-   - Deferring match copy and interspersed it with decoding subsequent codes
-   - Swapping literal/length else
-   - Swapping window/direct else
-   - Larger unrolled copy loops (three is about right)
-   - Moving len -= 3 statement into middle of loop
- */
-
-#endif /* !ASMINF */