--- a/zlib/infback.c	Sun Jun 15 15:39:16 2025 -0700
+++ b/zlib/infback.c	Sun Jun 15 15:39:33 2025 -0700
@@ -1,5 +1,5 @@
 /* infback.c -- inflate using a call-back interface
- * Copyright (C) 1995-2016 Mark Adler
+ * Copyright (C) 1995-2022 Mark Adler
  * For conditions of distribution and use, see copyright notice in zlib.h
  */
 
@@ -15,9 +15,6 @@
 #include "inflate.h"
 #include "inffast.h"
 
-/* function prototypes */
-local void fixedtables OF((struct inflate_state FAR *state));
-
 /*
    strm provides memory allocation functions in zalloc and zfree, or
    Z_NULL to use the library memory allocation functions.
@@ -25,13 +22,9 @@
    windowBits is in the range 8..15, and window is a user-supplied
    window and output buffer that is 2**windowBits bytes.
  */
-int ZEXPORT inflateBackInit_(strm, windowBits, window, version, stream_size)
-z_streamp strm;
-int windowBits;
-unsigned char FAR *window;
-const char *version;
-int stream_size;
-{
+int ZEXPORT inflateBackInit_(z_streamp strm, int windowBits,
+                             unsigned char FAR *window, const char *version,
+                             int stream_size) {
     struct inflate_state FAR *state;
 
     if (version == Z_NULL || version[0] != ZLIB_VERSION[0] ||
@@ -66,6 +59,7 @@
     state->window = window;
     state->wnext = 0;
     state->whave = 0;
+    state->sane = 1;
     return Z_OK;
 }
 
@@ -79,9 +73,7 @@
    used for threaded applications, since the rewriting of the tables and virgin
    may not be thread-safe.
  */
-local void fixedtables(state)
-struct inflate_state FAR *state;
-{
+local void fixedtables(struct inflate_state FAR *state) {
 #ifdef BUILDFIXED
     static int virgin = 1;
     static code *lenfix, *distfix;
@@ -247,13 +239,8 @@
    inflateBack() can also return Z_STREAM_ERROR if the input parameters
    are not correct, i.e. strm is Z_NULL or the state was not initialized.
  */
-int ZEXPORT inflateBack(strm, in, in_desc, out, out_desc)
-z_streamp strm;
-in_func in;
-void FAR *in_desc;
-out_func out;
-void FAR *out_desc;
-{
+int ZEXPORT inflateBack(z_streamp strm, in_func in, void FAR *in_desc,
+                        out_func out, void FAR *out_desc) {
     struct inflate_state FAR *state;
     z_const unsigned char FAR *next;    /* next input */
     unsigned char FAR *put;     /* next output */
@@ -477,6 +464,7 @@
             }
             Tracev((stderr, "inflate:       codes ok\n"));
             state->mode = LEN;
+                /* fallthrough */
 
         case LEN:
             /* use inflate_fast() if we have enough input and output */
@@ -604,33 +592,33 @@
             break;
 
         case DONE:
-            /* inflate stream terminated properly -- write leftover output */
+            /* inflate stream terminated properly */
             ret = Z_STREAM_END;
-            if (left < state->wsize) {
-                if (out(out_desc, state->window, state->wsize - left))
-                    ret = Z_BUF_ERROR;
-            }
             goto inf_leave;
 
         case BAD:
             ret = Z_DATA_ERROR;
             goto inf_leave;
 
-        default:                /* can't happen, but makes compilers happy */
+        default:
+            /* can't happen, but makes compilers happy */
             ret = Z_STREAM_ERROR;
             goto inf_leave;
         }
 
-    /* Return unused input */
+    /* Write leftover output and return unused input */
   inf_leave:
+    if (left < state->wsize) {
+        if (out(out_desc, state->window, state->wsize - left) &&
+            ret == Z_STREAM_END)
+            ret = Z_BUF_ERROR;
+    }
     strm->next_in = next;
     strm->avail_in = have;
     return ret;
 }
 
-int ZEXPORT inflateBackEnd(strm)
-z_streamp strm;
-{
+int ZEXPORT inflateBackEnd(z_streamp strm) {
     if (strm == Z_NULL || strm->state == Z_NULL || strm->zfree == (free_func)0)
         return Z_STREAM_ERROR;
     ZFREE(strm, strm->state);