cb99f0b11bdeee5dfa76064d38b6410da0f4a709
max
  Thu Sep 10 00:55:21 2026 -0700
Centralize CGI Content-Type printing in one cgiPrintContentType() helper

Around 90 places across the tree hand-rolled the CGI response header, each
with its own spelling: "Content-Type:" or "Content-type:", \n or \r\n, and
the terminating blank line written as part of the same string, as a separate
puts("\n") (which emits two newlines, so a stray blank line led the body) or
as printf("\r\n\r\n") (two blank lines).  A handful forgot the terminator
entirely and relied on a following header to supply it.

cgiPrintContentType() in lib/cheapcgi.c now writes the Content-Type line and
the blank line that ends the header.  Header lines are not ordered, so the
callers that also send Status, Set-Cookie, Content-Disposition, Content-Length
or X-Sendfile write those first and call this last to close the header; that
keeps it to a single helper rather than a print-the-line / end-the-header pair
that a caller can half-use.  cart.c's existing httpHeaders list already worked
this way.

Only the CGI response path is touched.  The dyStringPrintf("Content-type: ...")
calls that build outgoing HTTP *requests* (genomeSpace, oauthLogin, eapMetaSync,
edwWebAuthLogin, ga4ghToBed) are unrelated and left alone.

Also fills out the apiKey error message in botDelay.c to say where to create a
key and that keys are server-specific.

No behavior change on the wire beyond dropping those stray blank lines and
adding the missing newline after Retry-After.

diff --git src/hg/hgGenome/hgGenome.c src/hg/hgGenome/hgGenome.c
index fb4a0d00044..291599ec094 100644
--- src/hg/hgGenome/hgGenome.c
+++ src/hg/hgGenome/hgGenome.c
@@ -522,31 +522,31 @@
     {
     /* Default case - start fancy web page. */
     if (cgiVarExists(hggPsOutput))
     	handlePostscript(conn);
     else
 	mainPage(conn);
     }
 cartRemovePrefix(cart, hggDo);
 }
 
 void hggDoUsualHttp()
 /* Wrap html page dispatcher with code that writes out
  * HTTP header and write cart back to database. */
 {
 cartWriteCookie(cart, hUserCookie());
-printf("Content-Type:text/html\r\n\r\n");
+cgiPrintContentType("text/html");
 
 /* Dispatch other pages, that actually want to write HTML. */
 cartWarnCatcher(dispatchPage, cart, cartEarlyWarningHandler);
 cartCheckout(&cart);
 }
 
 
 void dispatchLocation()
 /* When this is called no output has been written at all.  We
  * look at command variables in cart and figure out if we just
  * are going write an HTTP location line, which happens when we
  * want to invoke say the genome browser or gene sorter without 
  * another intermediate page.  If we need to do more than that
  * then we call hggDoUsualHttp. */
 {