From: Nathan Moinvaziri <nathan@nathanm.com>
Date: Sun, 20 Sep 2020 17:51:05 +0000 (-0700)
Subject: Remove NIL preprocessor macro which isn't consistently enforced.
X-Git-Tag: 1.9.9-b1~23
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1c58894c679f8d4e930715bc3b670481c0854431;p=thirdparty%2Fzlib-ng.git

Remove NIL preprocessor macro which isn't consistently enforced.
---

diff --git a/deflate.c b/deflate.c
index 86842debf..a1553aaf4 100644
--- a/deflate.c
+++ b/deflate.c
@@ -126,9 +126,6 @@ extern void copy_with_crc(PREFIX3(stream) *strm, unsigned char *dst, unsigned lo
  * Local data
  */
 
-#define NIL 0
-/* Tail of hash chains */
-
 /* Values for max_lazy_match, good_match and max_chain_length, depending on
  * the desired pack level (0..9). The values given below have been tuned to
  * exclude worst case performance for pathological files. Better values may be
@@ -202,7 +199,7 @@ Z_INTERNAL void slide_hash_c(deflate_state *s) {
     do {
         unsigned m;
         m = *--p;
-        *p = (Pos)(m >= wsize ? m-wsize : NIL);
+        *p = (Pos)(m >= wsize ? m-wsize : 0);
     } while (--n);
 #else
     /* As of I make this change, gcc (4.8.*) isn't able to vectorize
@@ -219,7 +216,7 @@ Z_INTERNAL void slide_hash_c(deflate_state *s) {
         for (i = 0; i < n; i++) {
             Pos m = *q;
             Pos t = wsize;
-            *q++ = (Pos)(m >= t ? m-t: NIL);
+            *q++ = (Pos)(m >= t ? m-t: 0);
         }
     }
 #endif /* NOT_TWEAK_COMPILER */
@@ -230,7 +227,7 @@ Z_INTERNAL void slide_hash_c(deflate_state *s) {
     do {
         unsigned m;
         m = *--p;
-        *p = (Pos)(m >= wsize ? m-wsize : NIL);
+        *p = (Pos)(m >= wsize ? m-wsize : 0);
         /* If n is not on any hash chain, prev[n] is garbage but
          * its value will never be used.
          */
@@ -242,7 +239,7 @@ Z_INTERNAL void slide_hash_c(deflate_state *s) {
         for (i = 0; i < n; i++) {
             Pos m = *q;
             Pos t = wsize;
-            *q++ = (Pos)(m >= t ? m-t: NIL);
+            *q++ = (Pos)(m >= t ? m-t: 0);
         }
     }
 #endif /* NOT_TWEAK_COMPILER */
diff --git a/deflate.h b/deflate.h
index b42dc28d2..cf4afb957 100644
--- a/deflate.h
+++ b/deflate.h
@@ -21,10 +21,6 @@
 #  define GZIP
 #endif
 
-#define NIL 0
-/* Tail of hash chains */
-
-
 /* ===========================================================================
  * Internal compression state.
  */
@@ -157,7 +153,7 @@ typedef struct internal_state {
      * An index in this array is thus a window index modulo 32K.
      */
 
-    Pos *head; /* Heads of the hash chains or NIL. */
+    Pos *head; /* Heads of the hash chains or 0. */
 
     int block_start;
     /* Window position at the beginning of the current output block. Gets
diff --git a/deflate_slow.c b/deflate_slow.c
index af2f28449..ea5eed844 100644
--- a/deflate_slow.c
+++ b/deflate_slow.c
@@ -38,7 +38,7 @@ Z_INTERNAL block_state deflate_slow(deflate_state *s, int flush) {
         /* Insert the string window[strstart .. strstart+2] in the
          * dictionary, and set hash_head to the head of the hash chain:
          */
-        hash_head = NIL;
+        hash_head = 0;
         if (LIKELY(s->lookahead >= MIN_MATCH)) {
             hash_head = functable.quick_insert_string(s, s->strstart);
         }
@@ -48,7 +48,7 @@ Z_INTERNAL block_state deflate_slow(deflate_state *s, int flush) {
         s->prev_match = (Pos)s->match_start;
         match_len = MIN_MATCH-1;
 
-        if (hash_head != NIL && s->prev_length < s->max_lazy_match && s->strstart - hash_head <= MAX_DIST(s)) {
+        if (hash_head != 0 && s->prev_length < s->max_lazy_match && s->strstart - hash_head <= MAX_DIST(s)) {
             /* To simplify the code, we prevent matches with the string
              * of window index 0 (in particular we have to avoid a match
              * of the string with itself at the start of the input file).