Add a ./config --solo option to make zlib subset with no libary use

A common request has been the ability to compile zlib to require no
other libraries.  This --solo option provides that ability.  The price
is that the gz*, compress*, and uncompress functions are eliminated,
and that the user must provide memory allocation and free routines to
deflate and inflate when initializing.

1 files changed, 56 insertions, 20 deletions

diff --git a/example.c b/example.c
index c15cc03..f515a48 100644
--- a/example.c
+++ b/example.c
@@ -34,10 +34,6 @@ const char hello[] = "hello, hello!";
 const char dictionary[] = "hello";
 uLong dictId; /* Adler32 value of the dictionary */
 
-void test_compress      OF((Byte *compr, uLong comprLen,
-                            Byte *uncompr, uLong uncomprLen));
-void test_gzio          OF((const char *fname,
-                            Byte *uncompr, uLong uncomprLen));
 void test_deflate       OF((Byte *compr, uLong comprLen));
 void test_inflate       OF((Byte *compr, uLong comprLen,
                             Byte *uncompr, uLong uncomprLen));
@@ -53,6 +49,39 @@ void test_dict_inflate  OF((Byte *compr, uLong comprLen,
                             Byte *uncompr, uLong uncomprLen));
 int  main               OF((int argc, char *argv[]));
 
+
+#ifdef Z_SOLO
+
+void *myalloc OF((void *, unsigned, unsigned));
+void myfree OF((void *, void *));
+
+void *myalloc(q, n, m)
+    void *q;
+    unsigned n, m;
+{
+    q = Z_NULL;
+    return calloc(n, m);
+}
+
+void myfree(void *q, void *p)
+{
+    q = Z_NULL;
+    free(p);
+}
+
+static alloc_func zalloc = myalloc;
+static free_func zfree = myfree;
+
+#else /* !Z_SOLO */
+
+static alloc_func zalloc = (alloc_func)0;
+static free_func zfree = (free_func)0;
+
+void test_compress      OF((Byte *compr, uLong comprLen,
+                            Byte *uncompr, uLong uncomprLen));
+void test_gzio          OF((const char *fname,
+                            Byte *uncompr, uLong uncomprLen));
+
 /* ===========================================================================
  * Test compress() and uncompress()
  */
@@ -163,6 +192,8 @@ void test_gzio(fname, uncompr, uncomprLen)
 #endif
 }
 
+#endif /* Z_SOLO */
+
 /* ===========================================================================
  * Test deflate() with small buffers
  */
@@ -174,8 +205,8 @@ void test_deflate(compr, comprLen)
     int err;
     uLong len = (uLong)strlen(hello)+1;
 
-    c_stream.zalloc = (alloc_func)0;
-    c_stream.zfree = (free_func)0;
+    c_stream.zalloc = zalloc;
+    c_stream.zfree = zfree;
     c_stream.opaque = (voidpf)0;
 
     err = deflateInit(&c_stream, Z_DEFAULT_COMPRESSION);
@@ -213,8 +244,8 @@ void test_inflate(compr, comprLen, uncompr, uncomprLen)
 
     strcpy((char*)uncompr, "garbage");
 
-    d_stream.zalloc = (alloc_func)0;
-    d_stream.zfree = (free_func)0;
+    d_stream.zalloc = zalloc;
+    d_stream.zfree = zfree;
     d_stream.opaque = (voidpf)0;
 
     d_stream.next_in  = compr;
@@ -252,8 +283,8 @@ void test_large_deflate(compr, comprLen, uncompr, uncomprLen)
     z_stream c_stream; /* compression stream */
     int err;
 
-    c_stream.zalloc = (alloc_func)0;
-    c_stream.zfree = (free_func)0;
+    c_stream.zalloc = zalloc;
+    c_stream.zfree = zfree;
     c_stream.opaque = (voidpf)0;
 
     err = deflateInit(&c_stream, Z_BEST_SPEED);
@@ -309,8 +340,8 @@ void test_large_inflate(compr, comprLen, uncompr, uncomprLen)
 
     strcpy((char*)uncompr, "garbage");
 
-    d_stream.zalloc = (alloc_func)0;
-    d_stream.zfree = (free_func)0;
+    d_stream.zalloc = zalloc;
+    d_stream.zfree = zfree;
     d_stream.opaque = (voidpf)0;
 
     d_stream.next_in  = compr;
@@ -349,8 +380,8 @@ void test_flush(compr, comprLen)
     int err;
     uInt len = (uInt)strlen(hello)+1;
 
-    c_stream.zalloc = (alloc_func)0;
-    c_stream.zfree = (free_func)0;
+    c_stream.zalloc = zalloc;
+    c_stream.zfree = zfree;
     c_stream.opaque = (voidpf)0;
 
     err = deflateInit(&c_stream, Z_DEFAULT_COMPRESSION);
@@ -388,8 +419,8 @@ void test_sync(compr, comprLen, uncompr, uncomprLen)
 
     strcpy((char*)uncompr, "garbage");
 
-    d_stream.zalloc = (alloc_func)0;
-    d_stream.zfree = (free_func)0;
+    d_stream.zalloc = zalloc;
+    d_stream.zfree = zfree;
     d_stream.opaque = (voidpf)0;
 
     d_stream.next_in  = compr;
@@ -430,8 +461,8 @@ void test_dict_deflate(compr, comprLen)
     z_stream c_stream; /* compression stream */
     int err;
 
-    c_stream.zalloc = (alloc_func)0;
-    c_stream.zfree = (free_func)0;
+    c_stream.zalloc = zalloc;
+    c_stream.zfree = zfree;
     c_stream.opaque = (voidpf)0;
 
     err = deflateInit(&c_stream, Z_BEST_COMPRESSION);
@@ -469,8 +500,8 @@ void test_dict_inflate(compr, comprLen, uncompr, uncomprLen)
 
     strcpy((char*)uncompr, "garbage");
 
-    d_stream.zalloc = (alloc_func)0;
-    d_stream.zfree = (free_func)0;
+    d_stream.zalloc = zalloc;
+    d_stream.zfree = zfree;
     d_stream.opaque = (voidpf)0;
 
     d_stream.next_in  = compr;
@@ -540,10 +571,15 @@ int main(argc, argv)
         printf("out of memory\n");
         exit(1);
     }
+
+#ifdef Z_SOLO
+    argc = strlen(argv[0]);
+#else
     test_compress(compr, comprLen, uncompr, uncomprLen);
 
     test_gzio((argc > 1 ? argv[1] : TESTFILE),
               uncompr, uncomprLen);
+#endif
 
     test_deflate(compr, comprLen);
     test_inflate(compr, comprLen, uncompr, uncomprLen);