diff options
| -rw-r--r-- | networking/httpd.c | 47 |
1 files changed, 45 insertions, 2 deletions
diff --git a/networking/httpd.c b/networking/httpd.c index 2b0acd7dc..0f4f22669 100644 --- a/networking/httpd.c +++ b/networking/httpd.c @@ -1150,18 +1150,61 @@ static void send_headers(unsigned responseNum) file_size = range_end - range_start + 1; } #endif + +//RFC 2616 4.4 Message Length +// The transfer-length of a message is the length of the message-body as +// it appears in the message; that is, after any transfer-codings have +// been applied. When a message-body is included with a message, the +// transfer-length of that body is determined by one of the following +// (in order of precedence): +// 1.Any response message which "MUST NOT" include a message-body (such +// as the 1xx, 204, and 304 responses and any response to a HEAD +// request) is always terminated by the first empty line after the +// header fields, regardless of the entity-header fields present in +// the message. +// 2.If a Transfer-Encoding header field (section 14.41) is present and +// has any value other than "identity", then the transfer-length is +// defined by use of the "chunked" transfer-coding (section 3.6), +// unless the message is terminated by closing the connection. +// 3.If a Content-Length header field (section 14.13) is present, its +// decimal value in OCTETs represents both the entity-length and the +// transfer-length. The Content-Length header field MUST NOT be sent +// if these two lengths are different (i.e., if a Transfer-Encoding +// header field is present). If a message is received with both a +// Transfer-Encoding header field and a Content-Length header field, +// the latter MUST be ignored. +// 4.If the message uses the media type "multipart/byteranges" ... +// 5.By the server closing the connection. +// +// (NB: standards do not define "Transfer-Length:" _header_, +// transfer-length above is just a concept). + len += sprintf(iobuf + len, #if ENABLE_FEATURE_HTTPD_RANGES "Accept-Ranges: bytes\r\n" #endif "Last-Modified: %s\r\n" - "%s-Length: %"OFF_FMT"u\r\n", + /* Because of 4.4 (5), we can forgo sending of "Content-Length" + * since we close connection afterwards, but it helps clients + * to e.g. estimate download times, show progress bars etc. + * Theoretically we should not send it if page is compressed, + * but de-facto standard is to send it (see comment below). + */ + "Content-Length: %"OFF_FMT"u\r\n", date_str, - content_gzip ? "Transfer" : "Content", file_size ); } + /* This should be "Transfer-Encoding", not "Content-Encoding": + * "data is compressed for transfer", not "data is an archive". + * But many clients were not handling "Transfer-Encoding" correctly + * (they were not uncompressing gzipped pages, tried to show + * raw compressed data), and servers worked around it by using + * "Content-Encoding" instead... and this become de-facto standard. + * https://bugzilla.mozilla.org/show_bug.cgi?id=68517 + * https://bugs.chromium.org/p/chromium/issues/detail?id=94730 + */ if (content_gzip) len += sprintf(iobuf + len, "Content-Encoding: gzip\r\n"); |