Add undocumented inflateResetKeep() function for CAB file decoding.

The Microsoft CAB file format compresses each block with completed
deflate streams that depend on the sliding window history of the
previous block in order to decode.  inflateResetKeep() does what
inflateReset() does, except the sliding window history from the
previous inflate operation is retained.

11 files changed, 35 insertions, 12 deletions

diff --git a/as400/bndsrc b/as400/bndsrc
index dad2bc9..036cd63 100644
--- a/as400/bndsrc
+++ b/as400/bndsrc
@@ -180,5 +180,6 @@ STRPGMEXP PGMLVL(*CURRENT) SIGNATURE('ZLIB')
   EXPORT SYMBOL("inflatePrime")
   EXPORT SYMBOL("inflateReset2")
   EXPORT SYMBOL("inflateUndermine")
+  EXPORT SYMBOL("inflateResetKeep")
 
 ENDPGMEXP
diff --git a/as400/zlib.inc b/as400/zlib.inc
index 41ff616..976dca2 100644
--- a/as400/zlib.inc
+++ b/as400/zlib.inc
@@ -431,6 +431,10 @@
      D  strm                               like(z_stream)                       Expansion stream
      D  arg                          10I 0 value                                Error code
       *
+     D inflateResetKeep...
+     D                 PR            10I 0 extproc('inflateResetKeep')          End and init. stream
+     D  strm                               like(z_stream)                       Expansion stream
+      *
      D gzflags         PR            10U 0 extproc('gzflags')
       *
       /endif
diff --git a/contrib/vstudio/vc10/zlibvc.def b/contrib/vstudio/vc10/zlibvc.def
index 0d6dc38..d6ab1c1 100644
--- a/contrib/vstudio/vc10/zlibvc.def
+++ b/contrib/vstudio/vc10/zlibvc.def
@@ -128,7 +128,8 @@ EXPORTS
         inflatePrime                            @158

         inflateReset2                           @159

         inflateUndermine                        @160

-
-; zlib1 v1.2.6 added:
-        gzgetc_                                 @30
-        gzflags                                 @162
+

+; zlib1 v1.2.6 added:

+        gzgetc_                                 @30

+        gzflags                                 @162

+        inflateResetKeep                        @163

diff --git a/contrib/vstudio/vc9/zlibvc.def b/contrib/vstudio/vc9/zlibvc.def
index 0d6dc38..d6ab1c1 100644
--- a/contrib/vstudio/vc9/zlibvc.def
+++ b/contrib/vstudio/vc9/zlibvc.def
@@ -128,7 +128,8 @@ EXPORTS
         inflatePrime                            @158

         inflateReset2                           @159

         inflateUndermine                        @160

-
-; zlib1 v1.2.6 added:
-        gzgetc_                                 @30
-        gzflags                                 @162
+

+; zlib1 v1.2.6 added:

+        gzgetc_                                 @30

+        gzflags                                 @162

+        inflateResetKeep                        @163

diff --git a/inflate.c b/inflate.c
index cf10b01..e14b361 100644
--- a/inflate.c
+++ b/inflate.c
@@ -100,7 +100,7 @@ local int updatewindow OF((z_streamp strm, unsigned out));
 local unsigned syncsearch OF((unsigned FAR *have, unsigned char FAR *buf,
                               unsigned len));
 
-int ZEXPORT inflateReset(strm)
+int ZEXPORT inflateResetKeep(strm)
 z_streamp strm;
 {
     struct inflate_state FAR *state;
@@ -115,9 +115,6 @@ z_streamp strm;
     state->havedict = 0;
     state->dmax = 32768U;
     state->head = Z_NULL;
-    state->wsize = 0;
-    state->whave = 0;
-    state->wnext = 0;
     state->hold = 0;
     state->bits = 0;
     state->lencode = state->distcode = state->next = state->codes;
@@ -127,6 +124,19 @@ z_streamp strm;
     return Z_OK;
 }
 
+int ZEXPORT inflateReset(strm)
+z_streamp strm;
+{
+    struct inflate_state FAR *state;
+
+    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;
+    state = (struct inflate_state FAR *)strm->state;
+    state->wsize = 0;
+    state->whave = 0;
+    state->wnext = 0;
+    return inflateResetKeep(strm);
+}
+
 int ZEXPORT inflateReset2(strm, windowBits)
 z_streamp strm;
 int windowBits;
diff --git a/win32/zlib.def b/win32/zlib.def
index 93ea8bf..c420d8b 100644
--- a/win32/zlib.def
+++ b/win32/zlib.def
@@ -77,5 +77,6 @@ EXPORTS
     inflateSyncPoint
     get_crc_table
     inflateUndermine
+    inflateResetKeep
     gzgetc_
     gzflags
diff --git a/zconf.h b/zconf.h
index ed16b06..df7ff61 100644
--- a/zconf.h
+++ b/zconf.h
@@ -103,6 +103,7 @@
 #  define inflateSync           z_inflateSync
 #  define inflateSyncPoint      z_inflateSyncPoint
 #  define inflateUndermine      z_inflateUndermine
+#  define inflateResetKeep      z_inflateResetKeep
 #  define inflate_copyright     z_inflate_copyright
 #  define inflate_fast          z_inflate_fast
 #  define inflate_table         z_inflate_table
diff --git a/zconf.h.cmakein b/zconf.h.cmakein
index 84e4680..8450547 100644
--- a/zconf.h.cmakein
+++ b/zconf.h.cmakein
@@ -105,6 +105,7 @@
 #  define inflateSync           z_inflateSync
 #  define inflateSyncPoint      z_inflateSyncPoint
 #  define inflateUndermine      z_inflateUndermine
+#  define inflateResetKeep      z_inflateResetKeep
 #  define inflate_copyright     z_inflate_copyright
 #  define inflate_fast          z_inflate_fast
 #  define inflate_table         z_inflate_table
diff --git a/zconf.h.in b/zconf.h.in
index ed16b06..df7ff61 100644
--- a/zconf.h.in
+++ b/zconf.h.in
@@ -103,6 +103,7 @@
 #  define inflateSync           z_inflateSync
 #  define inflateSyncPoint      z_inflateSyncPoint
 #  define inflateUndermine      z_inflateUndermine
+#  define inflateResetKeep      z_inflateResetKeep
 #  define inflate_copyright     z_inflate_copyright
 #  define inflate_fast          z_inflate_fast
 #  define inflate_table         z_inflate_table
diff --git a/zlib.h b/zlib.h
index 96c2c14..99cd058 100644
--- a/zlib.h
+++ b/zlib.h
@@ -1687,6 +1687,7 @@ ZEXTERN const char   * ZEXPORT zError           OF((int));
 ZEXTERN int            ZEXPORT inflateSyncPoint OF((z_streamp));
 ZEXTERN const uLongf * ZEXPORT get_crc_table    OF((void));
 ZEXTERN int            ZEXPORT inflateUndermine OF((z_streamp, int));
+ZEXTERN int            ZEXPORT inflateResetKeep OF((z_streamp));
 #ifndef Z_SOLO
   ZEXTERN unsigned long  ZEXPORT gzflags          OF((void));
 #endif
diff --git a/zlib.map b/zlib.map
index 627133d..dd27591 100644
--- a/zlib.map
+++ b/zlib.map
@@ -74,4 +74,5 @@ ZLIB_1.2.5.1 {
 ZLIB_1.2.5.2 {
     gzflags;
     gzgetc_;
+    inflateResetKeep;
 } ZLIB_1.2.5.1;