Enable use of Exiv2::CurlIo

If needed, a dummy CurlIo class is used so SWIG generated files with
EXV_USE_CURL enabled can be linked with libexiv2 built with
EXV_USE_CURL disabled. Similarly SWIG generated files with EXV_USE_CURL
disabled can be linked with libexiv2 built with EXV_USE_CURL enabled.

src/interface/basicio.i

@@ -29,6 +29,7 @@
 %include "shared/enum.i"
 %include "shared/exception.i"
 %include "shared/keep_reference.i"
+%include "shared/remoteio_derived.i"
 %include "shared/unique_ptr.i"
 %include "shared/windows_path.i"
 
@@ -94,6 +95,10 @@ static swig_type_info* basicio_subtype(Exiv2::BasicIo* ptr) {
     else if (dynamic_cast<Exiv2::RemoteIo*>(ptr)) {
         if (dynamic_cast<Exiv2::HttpIo*>(ptr))
             return $descriptor(Exiv2::HttpIo*);
+#ifdef EXV_USE_CURL
+        else if (dynamic_cast<Exiv2::CurlIo*>(ptr))
+            return $descriptor(Exiv2::CurlIo*);
+#endif
         else
             return $descriptor(Exiv2::RemoteIo*);
     }
@@ -109,6 +114,16 @@ static swig_type_info* basicio_subtype(Exiv2::BasicIo* ptr) {
         ptr, basicio_subtype(ptr), SWIG_POINTER_OWN);
 }
 
+// CurlIo destructor isn't seen by SWIG in v0.27.x
+#if EXIV2_VERSION_HEX < 0x001c0000
+#ifdef EXV_USE_CURL
+%extend Exiv2::CurlIo {
+    ~CurlIo() {};
+}
+%ignore Exiv2::CurlIo::~CurlIo;
+#endif
+#endif
+
 // readOrThrow & seekOrThrow use ErrorCode internally without Exiv2:: prefix
 // as if SWIG doesn't realise ErrorCode is in the Exiv2 namespace
 %{
@@ -198,6 +213,7 @@ DEPRECATED_ENUM(BasicIo, Position, "Seek starting positions.",
 %ignore Exiv2::BasicIo::~BasicIo;
 %ignore Exiv2::BasicIo::bigBlock_;
 %ignore Exiv2::BasicIo::populateFakeData;
+%ignore Exiv2::curlWriter;
 %ignore Exiv2::IoCloser;
 %ignore Exiv2::ReplaceStringInPlace;
 %ignore Exiv2::readFile;

src/interface/image.i

@@ -29,6 +29,7 @@
 %include "shared/enum.i"
 %include "shared/exception.i"
 %include "shared/keep_reference.i"
+%include "shared/remoteio_derived.i"
 %include "shared/windows_path.i"
 
 %include "std_string.i"

src/interface/preview.i

@@ -30,6 +30,7 @@ For Exif thumbnail images see the :py:class:`ExifThumb` class.";
 %include "shared/buffers.i"
 %include "shared/exception.i"
 %include "shared/keep_reference.i"
+%include "shared/remoteio_derived.i"
 %include "shared/struct_dict.i"
 %include "shared/windows_path.i"
 

src/interface/shared/remoteio_derived.i

@@ -0,0 +1,37 @@
+// python-exiv2 - Python interface to libexiv2
+// http://github.com/jim-easterbrook/python-exiv2
+// Copyright (C) 2024  Jim Easterbrook  [email protected]
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+// Replacement for CurlIo missing from linked libexiv2
+// First ifdef EXV_USE_CURL detects SWIGging with EXV_USE_CURL set
+// Second ifndef EXV_USE_CURL detects compiling with EXV_USE_CURL unset
+#ifdef EXV_USE_CURL
+%{
+#ifndef EXV_USE_CURL
+namespace Exiv2 {
+    class CurlIo : public RemoteIo {
+    public:
+        CurlIo(const std::string& url, size_t blockSize=0) {
+            throw std::runtime_error(
+                "CurlIo not enabled in linked libexiv2");
+        };
+    };
+}
+#endif
+%}
+#endif
+

src/interface/version.i

@@ -39,13 +39,19 @@ EXCEPTION()
 
 // Function to report build options used
 %feature("docstring") versionInfo "Return a dict of libexiv2 build options."
+#ifndef EXV_USE_CURL
+%{
+#undef EXV_USE_CURL
+%}
+#endif
 %inline %{
 static PyObject* versionInfo() {
     bool nls = false;
     bool bmff = false;
     bool video = false;
     bool unicode = false;
     bool webready = false;
+    bool curl = false;
 #ifdef EXV_ENABLE_NLS
     nls = true;
 #endif
@@ -58,13 +64,17 @@ static PyObject* versionInfo() {
 #ifdef EXV_ENABLE_WEBREADY
     webready = true;
 #endif
-    return Py_BuildValue("{ss,sN,sN,sN,sN,sN}",
+#ifdef EXV_USE_CURL
+    curl = true;
+#endif
+    return Py_BuildValue("{ss,sN,sN,sN,sN,sN,sN}",
         "version", Exiv2::version(),
         "EXV_ENABLE_NLS", PyBool_FromLong(nls),
         "EXV_ENABLE_BMFF", PyBool_FromLong(bmff),
         "EXV_ENABLE_VIDEO", PyBool_FromLong(video),
         "EXV_UNICODE_PATH", PyBool_FromLong(unicode),
-        "EXV_ENABLE_WEBREADY", PyBool_FromLong(webready));
+        "EXV_ENABLE_WEBREADY", PyBool_FromLong(webready),
+        "EXV_USE_CURL", PyBool_FromLong(curl));
 };
 %}