Fix type error in initGEOS() call

The function pointers passed to initGEOS() did not have the correct
type.  A proper fix needs <stdarg.h> support in Cython, which is
currently missing.

This fixes a build failure with Clang 16 and GCC 14.

      src/_geoslib.c: In function ‘__pyx_pymod_exec__geoslib’:
      src/_geoslib.c:8803:12: error: passing argument 1 of ‘initGEOS’ from incompatible pointer type
       8803 |   initGEOS(__pyx_f_8_geoslib_notice_h, __pyx_f_8_geoslib_error_h);
            |            ^~~~~~~~~~~~~~~~~~~~~~~~~~
            |            |
            |            void (*)(char *, char *)
      In file included from src/_geoslib.c:1219:
      /usr/include/geos_c.h:2074:24: note: expected ‘GEOSMessageHandler’ {aka ‘void (*)(const char *, ...)’} but argument is of type ‘void (*)(char *, char *)’
       2074 |     GEOSMessageHandler notice_function,
            |     ~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~
      src/_geoslib.c:8803:40: error: passing argument 2 of ‘initGEOS’ from incompatible pointer type
       8803 |   initGEOS(__pyx_f_8_geoslib_notice_h, __pyx_f_8_geoslib_error_h);
            |                                        ^~~~~~~~~~~~~~~~~~~~~~~~~
            |                                        |
            |                                        void (*)(char *, char *)
      /usr/include/geos_c.h:2075:24: note: expected ‘GEOSMessageHandler’ {aka ‘void (*)(const char *, ...)’} but argument is of type ‘void (*)(char *, char *)’
       2075 |     GEOSMessageHandler error_function);
            |     ~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~

Author: fweimer-rh

packages/basemap/src/_geoslib.pyx

@@ -54,7 +54,7 @@ cdef extern from "geos_c.h":
     # Cython 3: Next ctypedef needs "noexcept" declaration unless
     # the compiler directive "legacy_implicit_noexcept" is used
     # ("noexcept" syntax supported since Cython 0.29.31).
-    ctypedef void (*GEOSMessageHandler)(char *fmt, char *list)
+    ctypedef void (*GEOSMessageHandler)(const char *fmt, ...)
     char *GEOSversion()
     void initGEOS(GEOSMessageHandler notice_function, GEOSMessageHandler error_function)
     void finishGEOS()
@@ -111,7 +111,7 @@ cdef extern from "geos_c.h":
 # Cython 3: Next cdef needs "noexcept" declaration unless
 # the compiler directive "legacy_implicit_noexcept" is used
 # ("noexcept" syntax supported since Cython 0.29.31).
-cdef void notice_h(char *fmt, char*msg):
+cdef void notice_h(const char *fmt, ...):
     pass
     #format = PyBytes_FromString(fmt)
     #message = PyBytes_FromString(msg)
@@ -124,7 +124,9 @@ cdef void notice_h(char *fmt, char*msg):
 # Cython 3: Next cdef needs "noexcept" declaration unless
 # the compiler directive "legacy_implicit_noexcept" is used
 # ("noexcept" syntax supported since Cython 0.29.31).
-cdef void error_h(char *fmt, char*msg):
+# FIXME: The type should be: error_h(const char *fmt, ...), but
+# Cython does not currently support varargs functions.
+cdef void error_h(const char *fmt, char*msg):
     format = PyBytes_FromString(fmt)
     message = PyBytes_FromString(msg)
     try:
@@ -142,7 +144,7 @@ __geos_major_version__ = GEOS_VERSION_MAJOR
 #     raise ValueError('version 2.2.3 of the geos library is required')
 
 # intialize GEOS (parameters are notice and error function callbacks).
-initGEOS(notice_h, error_h)
+initGEOS(notice_h, <GEOSMessageHandler>error_h)
 
 cdef class BaseGeometry:
     cdef GEOSGeometry *_geom