From 91182928a4827bd82512626d72f512d3ad7f0aa8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?C=C5=93ur?= <coeur@gmx.fr>
Date: Fri, 1 Nov 2024 23:33:52 +0100
Subject: [PATCH] avoid redefining already defined type

---
 compat/crypt.h | 13 +++++++++----
 mz_crypt.c     | 12 ++++++++----
 2 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/compat/crypt.h b/compat/crypt.h
index 46f2b67..af07aa7 100644
--- a/compat/crypt.h
+++ b/compat/crypt.h
@@ -26,10 +26,15 @@
 */
 
 #ifndef _ZLIB_H
-#  if (ZLIB_VERNUM < 0x1270)
-    typedef unsigned long z_crc_t;
-#  else
-    typedef uint32_t z_crc_t;
+#  ifndef ZLIB_VERNUM
+/* No zlib */
+typedef uint32_t z_crc_t;
+#  elif (ZLIB_VERNUM & 0xf != 0xf) && (ZLIB_VERNUM < 0x1270)
+/* Define z_crc_t in zlib 1.2.6 and less */
+typedef unsigned long z_crc_t;
+#  elif (ZLIB_VERNUM & 0xf == 0xf) && (ZLIB_VERNUM < 0x12df)
+/* Define z_crc_t in zlib-ng 2.0.7 and less */
+typedef unsigned int z_crc_t;
 #  endif
 #endif
 
diff --git a/mz_crypt.c b/mz_crypt.c
index 0b068e0..7a47ff2 100644
--- a/mz_crypt.c
+++ b/mz_crypt.c
@@ -34,11 +34,15 @@ int32_t mz_crypt_rand(uint8_t *buf, int32_t size) {
 
 uint32_t mz_crypt_crc32_update(uint32_t value, const uint8_t *buf, int32_t size) {
 #if defined(HAVE_ZLIB)
-    /* Define z_crc_t in zlib 1.2.5 and less or if using zlib-ng */
-#  if (ZLIB_VERNUM < 0x1270)
-    typedef unsigned long z_crc_t;
-#  else
+#  ifndef ZLIB_VERNUM
+    /* HAVE_ZLIB but no ZLIB_VERNUM? */
     typedef uint32_t z_crc_t;
+#  elif (ZLIB_VERNUM & 0xf != 0xf) && (ZLIB_VERNUM < 0x1270)
+    /* Define z_crc_t in zlib 1.2.6 and less */
+    typedef unsigned long z_crc_t;
+#  elif (ZLIB_VERNUM & 0xf == 0xf) && (ZLIB_VERNUM < 0x12df)
+    /* Define z_crc_t in zlib-ng 2.0.7 and less */
+    typedef unsigned int z_crc_t;
 #  endif
     return (uint32_t)ZLIB_PREFIX(crc32)((z_crc_t)value, buf, (uInt)size);
 #elif defined(HAVE_LZMA)