libcurlwrapper
This library loads CURL from an Aroma Module instead of statically linking it to the binary. This results in a much smaller binary size (saves about 750KiB).
- Requires the CURLWrapperModule to be running via WUMSLoader.
- Requires wut for building.
- Use with curl 7.84.0 headers, other versions might not be compatible.
- See important changes in the Usage section.
Install via make install.
Usage
Make sure to define this in your Makefile:
WUMS_ROOT := $(DEVKITPRO)/wums
Use the normal curl headers, but link against -lcurlwrapper instead. For example replace -lcurl -lmbedtls -lmbedx509 -lmbedcrypto -lz with -lcurlwrapper.
If the CURLWrapperModule is not loaded curl_global_init will return a negative value.
Changes compared to normal CURL
libcurlwrapper tries to be a drop-in replacement for libcurl, but some things need to be considered.
All function are only available between calling curl_global_init and curl_global_cleanup.
Even functions like curl_version only work after calling curl_global_init.
Calling curl_easy_init will automatically add CA certificates.
It curl_easy_init returns success, curl_easy_setopt(curl, CURLOPT_CAINFO_BLOB, &blob); with current CA certificates will be called.
These CA certificates are coming from the modules and can be updated in the future.
CURLOPT_SOCKOPTFUNCTION
- The CURLOPT_SOCKOPTFUNCTIONcallback requires a workaround to work properly.
- This is caused by setsockoptnot being compatible with the sockets from the CURLWrapperModule.
Currently, there are two options to get the correct setsockopt function:
Option 1: CURLOPT_SOCKOPTDATA
- To get a pointer to the correct setsockoptfunction, you have to set theCURLOPT_SOCKOPTDATAto 0x13371337.
- The 0x13371337will be replaced with a pointer to the correctsetsockoptfunction.
Example:
static int initSocket(void *ptr, curl_socket_t socket, curlsocktype type) {    
  int r;
  // If ptr is not our magic value, it got replaced with a pointer to a valid setsockopt function.
  if ((uint32_t) ptr != 0x13371337) {
      r = reinterpret_cast<decltype(&setsockopt)>(ptr)(socket, SOL_SOCKET, SO_WINSCALE, &o, sizeof(o));
  } else {
      r = setsockopt(socket, SOL_SOCKET, SO_WINSCALE, &o, sizeof(o));
  }
   return r == 0 ? CURL_SOCKOPT_OK : CURL_SOCKOPT_ERROR;
}
[...]
// Set socktopt data to a magic value to get a pointer to the correct setsockopt function.
curl_easy_setopt(curl, CURLOPT_SOCKOPTDATA, 0x13371337);
curl_easy_setopt(curl, CURLOPT_SOCKOPTFUNCTION, initSocket);
Downside of this option: the data pointer of CURLOPT_SOCKOPTFUNCTION can not be used.
Option 2: curlwrapper_setsockopt
This lib exposes the function curlwrapper_setsockopt which will call the correct function. Because this lib had no headers, you have to
declare it in your app like this:
int curlwrapper_setsockopt(int sockfd, int level, int optname, const void *optval, socklen_t optlen);
When using C++, you have to add extern "C" at the start.
Downside of this option: Linking to the original libcurl fails because curlwrapper_setsockopt is only defined in this wrapper lib.
Use this lib in Dockerfiles.
A prebuilt version of this lib can found on dockerhub. To use it for your projects, add this to your Dockerfile.
[...]
COPY --from=ghcr.io/wiiu-env/libcurlwrapper:[tag] /artifacts $DEVKITPRO
[...]
Replace [tag] with a tag you want to use, a list of tags can be found here.
It's highly recommended to pin the version to the latest date instead of using latest.
Format the code via docker
docker run --rm -v ${PWD}:/src ghcr.io/wiiu-env/clang-format:13.0.0-2 -r ./source -i
