Unfortunately, some Webservers (e.g. IIS) do not implement the (F)CGI
specifications correctly wrt. chunked uploads (i.e. Transfer-encoding:
chunked), but instead pass -1 as CONTENT_LENGTH to the CGI
application. However, our (F)CFI SAPIs (i.e. cgi and cgi-fcgi) do not
support this.
Therefore we try to retrieve the stream size in advance and pass it to
`curl_mime_data_cb()` to prevent libcurl from doing chunked uploads.
This is basically the same approach that `curl_mime_filedata()`
implements, except that we are keeping already opened streams open for
the `read_cb()`.
To cater to `curl_copy_handle()` of cURL handles with attached
`CURLFile`s, we must not attach the opened stream, because the stream
may not be seekable, so that we could rewind, when the same stream is
going to be uploaded multiple times. Instead, we're opening the stream
lazily in the read callback.
Since `curl_multi_perfom()` processes easy handles asynchronously, we
have no control of the operation sequence. Since duplicated cURL
handles may be used with multi handles, we cannot use a single arg
structure, but actually have to rebuild the whole mime structure on
handle duplication and attach this to the new handle.
In order to better test this behavior, we extend the test responder to
print the size of the upload, and patch the existing tests accordingly.
Not all systems support the discard protocol (TCP port 9), and since
there is no particular reason to use it, we switch to using actual
server testing.
libcurl 7.29.0 has been released almost eight years ago, so this
version is supposed to be available practically everywhere. This bump
also allows us to get rid of quite some conditional code and tests
catering to very old libcurl versions.
Depending on the libcurl version and perhaps configuration, it may show
additional info (due to `CURLOPT_VERBOSE` being activated), which we
have to ignore, to avoid spurious test failures.
Due to former restrictions of the libcurl API, curl multipart/formdata
file uploads supported only proper files. However, as of curl 7.56.0
the new `curl_mime_*()` API is available (and already supported by
PHP[1]), which allows us to support arbitrary *seekable* streams, which
is generally desirable, and particularly resolves issues with the
transparent Unicode and long part support on Windows (see bug #77711).
Note that older curl versions are still supported, but CURLFile is
still restricted to proper files in this case.
[1] <http://git.php.net/?p=php-src.git;a=commit;h=a83b68ba56714bfa06737a61af795460caa4a105>
(cherry picked from commit c68dc6b5e3)
As of curl 7.56.0, `curl_formadd()` is deprecated in favor of
`curl_mime_*()`, so we use the latter if available.
(cherry picked from commit a83b68ba56)
Clear the OpenSSL error queue before performing SSL stream operations.
As we don't control all code that could possibly be using OpenSSL,
we can't rely on the error queue being empty.
Máté Kocsis