zlib 1.0.8v1.0.8

1 files changed, 96 insertions, 16 deletions

diff --git a/trees.c b/trees.c
index fe86c77..e2c230f 100644
--- a/trees.c
+++ b/trees.c
@@ -31,6 +31,8 @@
 
 /* @(#) $Id$ */
 
+/* #define GEN_TREES_H */
+
 #include "deflate.h"
 
 #ifdef DEBUG
@@ -80,6 +82,11 @@ local const uch bl_order[BL_CODES]
  * Local data. These are initialized only once.
  */
 
+#define DIST_CODE_LEN  512 /* see definition of array dist_code below */
+
+#if defined(GEN_TREES_H) || !defined(STDC)
+/* non ANSI compilers may not accept trees.h */
+
 local ct_data static_ltree[L_CODES+2];
 /* The static literal tree. Since the bit lengths are imposed, there is no
  * need for the L_CODES extra codes used during heap construction. However
@@ -92,8 +99,8 @@ local ct_data static_dtree[D_CODES];
  * 5 bits.)
  */
 
-local uch dist_code[512];
-/* distance codes. The first 256 values correspond to the distances
+local uch dist_code[DIST_CODE_LEN];
+/* Distance codes. The first 256 values correspond to the distances
  * 3 .. 258, the last 256 values correspond to the top 8 bits of
  * the 15 bit distances.
  */
@@ -107,8 +114,12 @@ local int base_length[LENGTH_CODES];
 local int base_dist[D_CODES];
 /* First normalized distance for each code (0 = distance of 1) */
 
+#else
+#  include "trees.h"
+#endif /* GEN_TREES_H */
+
 struct static_tree_desc_s {
-    ct_data *static_tree;        /* static tree or NULL */
+    const ct_data *static_tree;  /* static tree or NULL */
     const intf *extra_bits;      /* extra bits for each code or NULL */
     int     extra_base;          /* base index for extra_bits */
     int     elems;               /* max number of elements in the tree */
@@ -122,7 +133,7 @@ local static_tree_desc  static_d_desc =
 {static_dtree, extra_dbits, 0,          D_CODES, MAX_BITS};
 
 local static_tree_desc  static_bl_desc =
-{(ct_data *)0, extra_blbits, 0,      BL_CODES, MAX_BL_BITS};
+{(const ct_data *)0, extra_blbits, 0,   BL_CODES, MAX_BL_BITS};
 
 /* ===========================================================================
  * Local (static) routines in this file.
@@ -148,6 +159,10 @@ local void bi_flush       OF((deflate_state *s));
 local void copy_block     OF((deflate_state *s, charf *buf, unsigned len,
                               int header));
 
+#ifdef GEN_TREES_H
+local void gen_trees_header OF((void));
+#endif
+
 #ifndef DEBUG
 #  define send_code(s, c, tree) send_bits(s, tree[c].Code, tree[c].Len)
    /* Send a code of the given tree. c and tree must not have side effects */
@@ -226,12 +241,11 @@ local void send_bits(s, value, length)
 /* the arguments must not have side effects */
 
 /* ===========================================================================
- * Initialize the various 'constant' tables. In a multi-threaded environment,
- * this function may be called by two threads concurrently, but this is
- * harmless since both invocations do exactly the same thing.
+ * Initialize the various 'constant' tables.
  */
 local void tr_static_init()
 {
+#if defined(GEN_TREES_H) || !defined(STDC)
     static int static_init_done = 0;
     int n;        /* iterates over tree elements */
     int bits;     /* bit counter */
@@ -295,7 +309,73 @@ local void tr_static_init()
         static_dtree[n].Code = bi_reverse((unsigned)n, 5);
     }
     static_init_done = 1;
+
+#  ifdef GEN_TREES_H
+    gen_trees_header();
+#  endif
+#endif /* defined(GEN_TREES_H) || !defined(STDC) */
+}
+
+/* ===========================================================================
+ * Genererate the file trees.h describing the static trees.
+ */
+#ifdef GEN_TREES_H
+#  ifndef DEBUG
+#    include <stdio.h>
+#  endif
+
+#  define SEPARATOR(i, last, width) \
+      ((i) == (last)? "\n};\n\n" :    \
+       ((i) % (width) == (width)-1 ? ",\n" : ", "))
+
+void gen_trees_header()
+{
+    FILE *header = fopen("trees.h", "w");
+    int i;
+
+    Assert (header != NULL, "Can't open trees.h");
+    fprintf(header,
+            "/* header created automatically with -DGEN_TREES_H */\n\n");
+
+    fprintf(header, "local const ct_data static_ltree[L_CODES+2] = {\n");
+    for (i = 0; i < L_CODES+2; i++) {
+        fprintf(header, "{{%3u},{%3u}}%s", static_ltree[i].Code,
+                static_ltree[i].Len, SEPARATOR(i, L_CODES+1, 5));
+    }
+
+    fprintf(header, "local const ct_data static_dtree[D_CODES] = {\n");
+    for (i = 0; i < D_CODES; i++) {
+        fprintf(header, "{{%2u},{%2u}}%s", static_dtree[i].Code,
+                static_dtree[i].Len, SEPARATOR(i, D_CODES-1, 5));
+    }
+
+    fprintf(header, "local const uch dist_code[DIST_CODE_LEN] = {\n");
+    for (i = 0; i < DIST_CODE_LEN; i++) {
+        fprintf(header, "%2u%s", dist_code[i],
+                SEPARATOR(i, DIST_CODE_LEN-1, 20));
+    }
+
+    fprintf(header, "local const uch length_code[MAX_MATCH-MIN_MATCH+1]= {\n");
+    for (i = 0; i < MAX_MATCH-MIN_MATCH+1; i++) {
+        fprintf(header, "%2u%s", length_code[i],
+                SEPARATOR(i, MAX_MATCH-MIN_MATCH, 20));
+    }
+
+    fprintf(header, "local const int base_length[LENGTH_CODES] = {\n");
+    for (i = 0; i < LENGTH_CODES; i++) {
+        fprintf(header, "%1u%s", base_length[i],
+                SEPARATOR(i, LENGTH_CODES-1, 20));
+    }
+
+    fprintf(header, "local const int base_dist[D_CODES] = {\n");
+    for (i = 0; i < D_CODES; i++) {
+        fprintf(header, "%5u%s", base_dist[i],
+                SEPARATOR(i, D_CODES-1, 10));
+    }
+
+    fclose(header);
 }
+#endif /* GEN_TREES_H */
 
 /* ===========================================================================
  * Initialize the tree data structures for a new zlib stream.
@@ -413,12 +493,12 @@ local void gen_bitlen(s, desc)
     deflate_state *s;
     tree_desc *desc;    /* the tree descriptor */
 {
-    ct_data *tree  = desc->dyn_tree;
-    int max_code   = desc->max_code;
-    ct_data *stree = desc->stat_desc->static_tree;
-    const intf *extra = desc->stat_desc->extra_bits;
-    int base       = desc->stat_desc->extra_base;
-    int max_length = desc->stat_desc->max_length;
+    ct_data *tree        = desc->dyn_tree;
+    int max_code         = desc->max_code;
+    const ct_data *stree = desc->stat_desc->static_tree;
+    const intf *extra    = desc->stat_desc->extra_bits;
+    int base             = desc->stat_desc->extra_base;
+    int max_length       = desc->stat_desc->max_length;
     int h;              /* heap index */
     int n, m;           /* iterate over the tree elements */
     int bits;           /* bit length */
@@ -542,9 +622,9 @@ local void build_tree(s, desc)
     deflate_state *s;
     tree_desc *desc; /* the tree descriptor */
 {
-    ct_data *tree   = desc->dyn_tree;
-    ct_data *stree  = desc->stat_desc->static_tree;
-    int elems       = desc->stat_desc->elems;
+    ct_data *tree         = desc->dyn_tree;
+    const ct_data *stree  = desc->stat_desc->static_tree;
+    int elems             = desc->stat_desc->elems;
     int n, m;          /* iterate over heap elements */
     int max_code = -1; /* largest code with non zero frequency */
     int node;          /* new node being created */