Change c_zlib further to allow loading a shared zlib on all operating

[openssl.git] / crypto / comp / c_zlib.c

diff --git a/crypto/comp/c_zlib.c b/crypto/comp/c_zlib.c
index 49be818dc72b012bf0648d3d9737fc58251d9834..a78bf97177369e63d07dc61a7d6df640696eb15a 100644 (file)
--- a/crypto/comp/c_zlib.c
+++ b/crypto/comp/c_zlib.c
@@ -1,16 +1,14 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include "objects.h"
-#include "comp.h"
+#include <openssl/objects.h>
+#include <openssl/comp.h>
 
 COMP_METHOD *COMP_zlib(void );
 
-#ifndef ZLIB
-
-static COMP_METHOD zlib_method={
+static COMP_METHOD zlib_method_nozlib={
        NID_undef,
-       "(null)",
+       "(undef)",
        NULL,
        NULL,
        NULL,
@@ -18,6 +16,8 @@ static COMP_METHOD zlib_method={
        NULL,
        };
 
+#ifndef ZLIB
+#undef ZLIB_SHARED
 #else
 
 #include <zlib.h>
@@ -40,6 +40,53 @@ static COMP_METHOD zlib_method={
        NULL,
        };
 
+/* 
+ * When OpenSSL is built on Windows, we do not want to require that
+ * the ZLIB.DLL be available in order for the OpenSSL DLLs to
+ * work.  Therefore, all ZLIB routines are loaded at run time
+ * and we do not link to a .LIB file.
+ */
+#if defined(WINDOWS) || defined(WIN32)
+# include <windows.h>
+
+# define Z_CALLCONV _stcall
+# define ZLIB_SHARED
+#else
+# define Z_CALLCONV
+#endif /* !(WINDOWS || WIN32) */
+
+#ifdef ZLIB_SHARED
+#include <openssl/dso.h>
+
+/* Prototypes for built in stubs */
+static int stub_compress(Bytef *dest,uLongf *destLen,
+       const Bytef *source, uLong sourceLen);
+static int stub_inflateEnd(z_streamp strm);
+static int stub_inflate(z_streamp strm, int flush);
+static int stub_inflateInit_(z_streamp strm, const char * version,
+       int stream_size);
+
+/* Function pointers */
+typedef int Z_CALLCONV (*compress_ft)(Bytef *dest,uLongf *destLen,
+       const Bytef *source, uLong sourceLen);
+typedef int Z_CALLCONV (*inflateEnd_ft)(z_streamp strm);
+typedef int Z_CALLCONV (*inflate_ft)(z_streamp strm, int flush);
+typedef int Z_CALLCONV (*inflateInit__ft)(z_streamp strm,
+       const char * version, int stream_size);
+static compress_ft     p_compress=NULL;
+static inflateEnd_ft   p_inflateEnd=NULL;
+static inflate_ft      p_inflate=NULL;
+static inflateInit__ft p_inflateInit_=NULL;
+
+static int zlib_loaded = 0;     /* only attempt to init func pts once */
+static DSO *zlib_dso = NULL;
+
+#define compress                stub_compress
+#define inflateEnd              stub_inflateEnd
+#define inflate                 stub_inflate
+#define inflateInit_            stub_inflateInit_
+#endif /* ZLIB_SHARED */
+
 static int zlib_compress_block(COMP_CTX *ctx, unsigned char *out,
             unsigned int olen, unsigned char *in, unsigned int ilen)
        {
@@ -66,7 +113,10 @@ static int zlib_compress_block(COMP_CTX *ctx, unsigned char *out,
                memcpy(&(out[1]),in,ilen);
                l=ilen+1;
                }
-fprintf(stderr,"compress(%4d)->%4d %s\n",ilen,(int)l,(clear)?"clear":"zlib");
+#ifdef DEBUG_ZLIB
+       fprintf(stderr,"compress(%4d)->%4d %s\n",
+               ilen,(int)l,(clear)?"clear":"zlib");
+#endif
        return((int)l);
        }
 
@@ -88,7 +138,10 @@ static int zlib_expand_block(COMP_CTX *ctx, unsigned char *out,
                memcpy(out,&(in[1]),ilen-1);
                l=ilen-1;
                }
-        fprintf(stderr,"expand  (%4d)->%4d %s\n",ilen,(int)l,in[0]?"zlib":"clear");
+#ifdef DEBUG_ZLIB
+        fprintf(stderr,"expand  (%4d)->%4d %s\n",
+               ilen,(int)l,in[0]?"zlib":"clear");
+#endif
        return((int)l);
        }
 
@@ -128,6 +181,78 @@ static int zz_uncompress (Bytef *dest, uLongf *destLen, const Bytef *source,
 
 COMP_METHOD *COMP_zlib(void)
        {
-       return(&zlib_method);
+       COMP_METHOD *meth = &zlib_method_nozlib;
+
+#ifdef ZLIB_SHARED
+       if (!zlib_loaded)
+               {
+#if defined(WINDOWS) || defined(WIN32)
+               zlib_dso = DSO_load(NULL, "ZLIB", NULL, 0);
+#else
+               zlib_dso = DSO_load(NULL, "z", NULL, 0);
+#endif
+               if (zlib_dso != NULL)
+                       {
+                       p_compress
+                               = (compress_ft) DSO_bind_func(zlib_dso,
+                                       "compress");
+                       p_inflateEnd
+                               = (inflateEnd_ft) DSO_bind_func(zlib_dso,
+                                       "inflateEnd");
+                       p_inflate
+                               = (inflate_ft) DSO_bind_func(zlib_dso,
+                                       "inflate");
+                       p_inflateInit_
+                               = (inflateInit__ft) DSO_bind_func(zlib_dso,
+                                       "inflateInit_");
+                       zlib_loaded++;
+                       meth = &zlib_method;
+                       }
+               }
+
+#elif defined(ZLIB)
+       meth = &zlib_method;
+#endif
+
+       return(meth);
+       }
+
+#ifdef ZLIB_SHARED
+/* Stubs for each function to be dynamicly loaded */
+static int 
+stub_compress(Bytef *dest,uLongf *destLen,const Bytef *source, uLong sourceLen)
+       {
+       if (p_compress)
+               return(p_compress(dest,destLen,source,sourceLen));
+       else
+               return(Z_MEM_ERROR);
+       }
+
+static int
+stub_inflateEnd(z_streamp strm)
+       {
+       if ( p_inflateEnd )
+               return(p_inflateEnd(strm));
+       else
+               return(Z_MEM_ERROR);
+       }
+
+static int
+stub_inflate(z_streamp strm, int flush)
+       {
+       if ( p_inflate )
+               return(p_inflate(strm,flush));
+       else
+               return(Z_MEM_ERROR);
+       }
+
+static int
+stub_inflateInit_(z_streamp strm, const char * version, int stream_size)
+       {
+       if ( p_inflateInit_ )
+               return(p_inflateInit_(strm,version,stream_size));
+       else
+               return(Z_MEM_ERROR);
        }
 
+#endif /* ZLIB_SHARED */