MINOR: http: make msg->eol carry the last CRLF length
One of the issues we face when we need to either forward headers only
before compressing, or rewind the stream during a redispatch is to know
the proper length of the request headers. msg->eoh always has the total
length up to the last CRLF, and we never know whether the request ended
with a single LF or a standard CRLF. This makes it hard to rewind the
headers without explicitly checking the bytes in the buffer.
Instead of doing so, we now use msg->eol to carry the length of the last
CRLF (either 1 or 2). Since it is not modified at all after HTTP_MSG_BODY,
and was only left in an undefined state, it is safe to use at any moment.
Thus, the complete header length to forward or to rewind now is always
msg->eoh + msg->eol.
diff --git a/include/types/proto_http.h b/include/types/proto_http.h
index 53e9fb4..95860c0 100644
--- a/include/types/proto_http.h
+++ b/include/types/proto_http.h
@@ -320,11 +320,22 @@
* for states after START. When in HTTP_MSG_BODY,
* eoh points to the first byte of the last CRLF
* preceeding data. Relative to buffer's origin.
+ * This value then remains unchanged till the end
+ * so that we can rewind the buffer to change some
+ * headers if needed (eg: http-send-name-header).
+ *
* - sov : When in HTTP_MSG_BODY, will point to the first
* byte of data (relative to buffer's origin).
* - sol (start of line) : start of current line during parsing, or zero.
- * - eol (End of Line) : relative offset in the buffer of the first byte
- * which marks the end of the line (LF or CRLF).
+ *
+ * - eol (End of Line) : Before HTTP_MSG_BODY, relative offset in the
+ * buffer of the first byte which marks the end of
+ * the line current (LF or CRLF).
+ * From HTTP_MSG_BODY to the end, contains the
+ * length of the last CRLF (1 for a plain LF, or 2
+ * for a true CRLF). So eoh+eol always contain the
+ * exact size of the header size.
+ *
* Note that all offsets are relative to the origin of the buffer (buf->p)
* which always points to the beginning of the message (request or response).
* Since a message may not wrap, pointer computations may be one without any
diff --git a/src/proto_http.c b/src/proto_http.c
index a1b064a..7c0b7fe 100644
--- a/src/proto_http.c
+++ b/src/proto_http.c
@@ -1731,12 +1731,16 @@
case HTTP_MSG_LAST_LF:
http_msg_last_lf:
- /* Assumes msg->sol points to the first of either CR or LF */
+ /* Assumes msg->sol points to the first of either CR or LF.
+ * Sets ->sov and ->next to the total header length, ->eoh to
+ * the last CRLF, and ->eol to the last CRLF length (1 or 2).
+ */
EXPECT_LF_HERE(ptr, http_msg_invalid);
ptr++;
msg->sov = msg->next = ptr - buf->p;
msg->eoh = msg->sol;
msg->sol = 0;
+ msg->eol = msg->sov - msg->eoh;
msg->msg_state = HTTP_MSG_BODY;
return;