Files
jak-project/third-party/curl/docs/libcurl/opts/CURLOPT_CUSTOMREQUEST.md
Alexander J. Semenuk 5d5e35fb9b fix: Windows toolchain compatibility (curl 8.21 re-vendor, endless reconfigure loop) (#4355)
## Problem

Windows builds break with a current local toolchain (Scoop LLVM 22.1.8,
CMake 4.4.0, VS 2026), in two independent ways:

1. The build stops at curl's deliberate guard: `#error "no non-blocking
method was found/used/set"` in `third-party/curl/lib/nonblock.c`.
2. From the second configure onward, `cmake --build` re-runs CMake in an
endless loop (observed 42 consecutive reconfigure cycles in a single
build). Likely the same mechanism behind the "endlessly building" VS
2026 note in `docs/setup/dev/vs.md`.

## Root cause

1. `third-party/curl/CMake/CurlTests.c` passes `int *` to
`ioctlsocket()`, whose third parameter is `u_long *`. Clang 22 promotes
`-Wincompatible-pointer-types` to a hard error in C, so the
`HAVE_IOCTLSOCKET_FIONBIO` try_compile silently fails and
`curl_config.h` never defines it. Upstream CI does not see this because
the windows-2022 runner image ships an older LLVM. GCC 14 promotes the
same warning to a hard error, which is very likely the `CurlTests.c.obj`
failure reported from MSYS2 in open-goal/jak-project#3551. Upstream curl
hit the identical problem with GCC 14 and fixed the probe in curl 8.8.0
(curl/curl#13578).
2. The root CMakeLists copies the build tree's `compile_commands.json`
into `<src>/build/` for clangd using `configure_file()`, which registers
its input as a configure dependency. CMake rewrites
`compile_commands.json` late in every generation, after
`CTestTestfile.cmake` and `cmake_install.cmake` (outputs of the same
Ninja regen rule), so once the dependency is registered the rule is
deterministically dirty and every `ninja` invocation re-runs CMake. A
pristine first configure is safe (the file does not exist yet, so the
`if(EXISTS ...)` guard skips the copy), which is why the loop looks
machine- or IDE-specific.

## Fix

1. Per review, re-vendor `third-party/curl` at the `curl-8_21_0` tag
(previously `curl-8_3_0`), which carries the upstream probe fix plus two
years of upstream development; `vendor.yaml` updated to match.
Adjustments the version jump forced:
- curl 8.15 removed the native macOS Secure Transport backend
(`CURL_USE_SECTRANSP`), so macOS now builds curl against OpenSSL like
Linux. The two macOS workflows install Homebrew `openssl@3` and export
`OPENSSL_ROOT_DIR` (keg-only), and the macOS setup docs gained the same
two lines.
- `CURL_BROTLI` / `CURL_ZSTD` switched to AUTO-detection in curl 8.10;
pinned OFF to keep the previous no-compression behavior and avoid
silently linking whatever the CI images happen to have.
- curl's new top-level `BUILD_EXAMPLES` cache option (default ON) leaked
into discord-rpc's identically named option and broke configure at a
nonexistent `examples/send-presence` directory; pinned OFF ahead of the
third-party subdirectories.

The diff is dominated by the mechanical tag-tree swap under
`third-party/curl` (linguist-vendored, collapsed in review). The
hand-written changes are `CMakeLists.txt`, the two macOS workflows,
`docs/setup/system/macos.md`, and `vendor.yaml`.
2. Swap `configure_file()` for `file(COPY ...)`: the same clangd copy
with no configure dependency registered. (`file(COPY_FILE ...
ONLY_IF_DIFFERENT)` would be cleaner still but requires CMake 3.21,
above the declared `cmake_minimum_required(VERSION 3.10)`.)

## Test plan

- [x] Fresh `cmake --preset Release-windows-clang` (LLVM 22, no cache
seeding) completes and logs `Enabled SSL backends: Schannel`; the
FIONBIO probe passes without the previous `#error`
- [x] Full Windows Release build from scratch in the branch worktree
(all 1422 targets)
- [x] goalc-test suite: 1509 passed, 0 failed
- [x] Second consecutive configure with `compile_commands.json` present:
the regen rule in `build.ninja` has no `compile_commands.json` input;
`<src>/build/compile_commands.json` is still refreshed for clangd
- [x] Repeated `ninja` invocations after a full build no longer re-run
CMake
- [x] macOS Intel and ARM CI green (first exercise of the OpenSSL
backend switch)

---

I work off a self-hosted forge, so this GitHub account is quiet; the
configure logs and ninja dirty-node traces from the investigation are
available if anyone wants the raw data.

(AI-assisted)
2026-07-27 19:19:18 -04:00

3.8 KiB
Vendored
Generated

c, SPDX-License-Identifier, Title, Section, Source, See-also, Protocol, Added-in
c SPDX-License-Identifier Title Section Source See-also Protocol Added-in
Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. curl CURLOPT_CUSTOMREQUEST 3 libcurl
CURLINFO_EFFECTIVE_METHOD (3)
CURLOPT_HTTPHEADER (3)
CURLOPT_NOBODY (3)
CURLOPT_REQUEST_TARGET (3)
HTTP
FTP
IMAP
POP3
SMTP
7.1

NAME

CURLOPT_CUSTOMREQUEST - custom request method

SYNOPSIS

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_CUSTOMREQUEST, char *method);

DESCRIPTION

Pass a pointer to a null-terminated string as parameter.

When changing the request method by setting CURLOPT_CUSTOMREQUEST(3), you do not actually change how libcurl behaves or acts: you only change the actual string sent in the request.

libcurl passes on the verbatim string in its request without any filter or other safe guards. That includes white space and control characters.

The application does not have to keep the string around after setting this option.

Using this option multiple times makes the last set string override the previous ones. Restore to the internal default by setting this to NULL.

This option can be used to specify the request:

HTTP

Instead of GET or HEAD when performing HTTP based requests. This is particularly useful, for example, for performing an HTTP DELETE request.

For example:

When you tell libcurl to do a HEAD request, but then specify a GET though a custom request libcurl still acts as if it sent a HEAD. To switch to a proper HEAD use CURLOPT_NOBODY(3), to switch to a proper POST use CURLOPT_POST(3) or CURLOPT_POSTFIELDS(3) and to switch to a proper GET use CURLOPT_HTTPGET(3).

Many people have wrongly used this option to replace the entire request with their own, including multiple headers and POST contents. While that might work in many cases, it might cause libcurl to send invalid requests and it could possibly confuse the remote server badly. Use CURLOPT_POST(3) and CURLOPT_POSTFIELDS(3) to set POST data. Use CURLOPT_HTTPHEADER(3) to replace or extend the set of headers sent by libcurl. Use CURLOPT_HTTP_VERSION(3) to change the HTTP version.

When this option is used together with CURLOPT_FOLLOWLOCATION(3), the custom set method overrides the method libcurl could otherwise change to for the subsequent requests. You can fine-tune that decision by using the CURLFOLLOW_OBEYCODE bit to CURLOPT_FOLLOWLOCATION(3) to make redirects adhere to the redirect response code as the protocol instructs.

FTP

Instead of LIST and NLST when performing FTP directory listings.

IMAP

Instead of LIST when issuing IMAP based requests.

POP3

Instead of LIST and RETR when issuing POP3 based requests.

For example:

When you tell libcurl to use a custom request it behaves like a LIST or RETR command was sent where it expects data to be returned by the server. As such CURLOPT_NOBODY(3) should be used when specifying commands such as DELE and NOOP for example.

SMTP

Instead of a HELP or VRFY when issuing SMTP based requests.

For example:

Normally a multi line response is returned which can be used, in conjunction with CURLOPT_MAIL_RCPT(3), to specify an EXPN request. If the CURLOPT_NOBODY(3) option is specified then the request can be used to issue NOOP and RSET commands.

DEFAULT

NULL

%PROTOCOLS%

EXAMPLE

int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode result;
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/foo.bin");

    /* DELETE the given path */
    curl_easy_setopt(curl, CURLOPT_CUSTOMREQUEST, "DELETE");

    result = curl_easy_perform(curl);

    curl_easy_cleanup(curl);
  }
}

%AVAILABILITY%

RETURN VALUE

curl_easy_setopt(3) returns a CURLcode indicating success or error.

CURLE_OK (0) means everything was OK, non-zero means an error occurred, see libcurl-errors(3).