This permits compilers to check for the proper treatment of next_in and
msg in the z_stream structure. This is an option instead of the default
in order to preserve backward compatibility. Some applications make use
of the z_stream structure outside of zlib, and perform operations such
as free(strm->next_in), which would not be permitted when next_in is
const. The #define ZLIB_CONST needs to precede the #include "zlib.h">,
in order to make next_in and msg const pointers in the z_stream type.
# endif
#endif
+#if defined(ZLIB_CONST) && !defined(z_const)
+# define z_const const
+#else
+# define z_const
+#endif
+
/* Some Mac compilers merge all .h files incorrectly: */
#if defined(__MWERKS__)||defined(applec)||defined(THINK_C)||defined(__SC__)
# define NO_DUMMY_DECL
# endif
#endif
+#if defined(ZLIB_CONST) && !defined(z_const)
+# define z_const const
+#else
+# define z_const
+#endif
+
/* Some Mac compilers merge all .h files incorrectly: */
#if defined(__MWERKS__)||defined(applec)||defined(THINK_C)||defined(__SC__)
# define NO_DUMMY_DECL
# endif
#endif
+#if defined(ZLIB_CONST) && !defined(z_const)
+# define z_const const
+#else
+# define z_const
+#endif
+
/* Some Mac compilers merge all .h files incorrectly: */
#if defined(__MWERKS__)||defined(applec)||defined(THINK_C)||defined(__SC__)
# define NO_DUMMY_DECL
struct internal_state;
typedef struct z_stream_s {
- Bytef *next_in; /* next input byte */
+ z_const Bytef *next_in; /* next input byte */
uInt avail_in; /* number of bytes available at next_in */
uLong total_in; /* total number of input bytes read so far */
uInt avail_out; /* remaining free space at next_out */
uLong total_out; /* total number of bytes output so far */
- char *msg; /* last error message, NULL if no error */
+ z_const char *msg; /* last error message, NULL if no error */
struct internal_state FAR *state; /* not visible by applications */
alloc_func zalloc; /* used to allocate the internal state */