+/* Add/remove/rewrite headers, and send them plus the empty-line separator.
+
+Globals:
+ header_list
+
+Arguments:
+ addr (chain of) addresses (for extra headers), or NULL;
+ only the first address is used
+ tctx transport context
+ sendfn function for output (transport or verify)
+
+Returns: TRUE on success; FALSE on failure.
+*/
+BOOL
+transport_headers_send(transport_ctx * tctx,
+ BOOL (*sendfn)(transport_ctx * tctx, uschar * s, int len))
+{
+header_line *h;
+const uschar *list;
+transport_instance * tblock = tctx ? tctx->tblock : NULL;
+address_item * addr = tctx ? tctx->addr : NULL;
+
+/* Then the message's headers. Don't write any that are flagged as "old";
+that means they were rewritten, or are a record of envelope rewriting, or
+were removed (e.g. Bcc). If remove_headers is not null, skip any headers that
+match any entries therein. It is a colon-sep list; expand the items
+separately and squash any empty ones.
+Then check addr->prop.remove_headers too, provided that addr is not NULL. */
+
+for (h = header_list; h; h = h->next) if (h->type != htype_old)
+ {
+ int i;
+ BOOL include_header = TRUE;
+
+ list = tblock ? tblock->remove_headers : NULL;
+ for (i = 0; i < 2; i++) /* For remove_headers && addr->prop.remove_headers */
+ {
+ if (list)
+ {
+ int sep = ':'; /* This is specified as a colon-separated list */
+ uschar *s, *ss;
+ while ((s = string_nextinlist(&list, &sep, NULL, 0)))
+ {
+ int len;
+
+ if (i == 0)
+ if (!(s = expand_string(s)) && !f.expand_string_forcedfail)
+ {
+ errno = ERRNO_CHHEADER_FAIL;
+ return FALSE;
+ }
+ len = s ? Ustrlen(s) : 0;
+ if (strncmpic(h->text, s, len) != 0) continue;
+ ss = h->text + len;
+ while (*ss == ' ' || *ss == '\t') ss++;
+ if (*ss == ':') break;
+ }
+ if (s) { include_header = FALSE; break; }
+ }
+ if (addr) list = addr->prop.remove_headers;
+ }
+
+ /* If this header is to be output, try to rewrite it if there are rewriting
+ rules. */
+
+ if (include_header)
+ {
+ if (tblock && tblock->rewrite_rules)
+ {
+ void *reset_point = store_get(0);
+ header_line *hh;
+
+ if ((hh = rewrite_header(h, NULL, NULL, tblock->rewrite_rules,
+ tblock->rewrite_existflags, FALSE)))
+ {
+ if (!sendfn(tctx, hh->text, hh->slen)) return FALSE;
+ store_reset(reset_point);
+ continue; /* With the next header line */
+ }
+ }
+
+ /* Either no rewriting rules, or it didn't get rewritten */
+
+ if (!sendfn(tctx, h->text, h->slen)) return FALSE;
+ }
+
+ /* Header removed */
+
+ else
+ DEBUG(D_transport) debug_printf("removed header line:\n%s---\n", h->text);
+ }
+
+/* Add on any address-specific headers. If there are multiple addresses,
+they will all have the same headers in order to be batched. The headers
+are chained in reverse order of adding (so several addresses from the
+same alias might share some of them) but we want to output them in the
+opposite order. This is a bit tedious, but there shouldn't be very many
+of them. We just walk the list twice, reversing the pointers each time,
+but on the second time, write out the items.
+
+Headers added to an address by a router are guaranteed to end with a newline.
+*/
+
+if (addr)
+ {
+ int i;
+ header_line *hprev = addr->prop.extra_headers;
+ header_line *hnext;
+ for (i = 0; i < 2; i++)
+ for (h = hprev, hprev = NULL; h; h = hnext)
+ {
+ hnext = h->next;
+ h->next = hprev;
+ hprev = h;
+ if (i == 1)
+ {
+ if (!sendfn(tctx, h->text, h->slen)) return FALSE;
+ DEBUG(D_transport)
+ debug_printf("added header line(s):\n%s---\n", h->text);
+ }
+ }
+ }
+
+/* If a string containing additional headers exists it is a newline-sep
+list. Expand each item and write out the result. This is done last so that
+if it (deliberately or accidentally) isn't in header format, it won't mess
+up any other headers. An empty string or a forced expansion failure are
+noops. An added header string from a transport may not end with a newline;
+add one if it does not. */
+
+if (tblock && (list = CUS tblock->add_headers))
+ {
+ int sep = '\n';
+ uschar * s;
+
+ while ((s = string_nextinlist(&list, &sep, NULL, 0)))
+ if ((s = expand_string(s)))
+ {
+ int len = Ustrlen(s);
+ if (len > 0)
+ {
+ if (!sendfn(tctx, s, len)) return FALSE;
+ if (s[len-1] != '\n' && !sendfn(tctx, US"\n", 1))
+ return FALSE;
+ DEBUG(D_transport)
+ {
+ debug_printf("added header line:\n%s", s);
+ if (s[len-1] != '\n') debug_printf("\n");
+ debug_printf("---\n");
+ }
+ }
+ }
+ else if (!f.expand_string_forcedfail)
+ { errno = ERRNO_CHHEADER_FAIL; return FALSE; }
+ }
+
+/* Separate headers from body with a blank line */
+
+return sendfn(tctx, US"\n", 1);
+}
+
+
git://git.exim.org / exim.git / blobdiff