Name message fields by paths and take variable fields where they are

A message field's name may now be a path of identifiers joined by dots
(user.name, a field inside the group user); a module that names both a
field and a group (user and user.name) is refused, as are empty,
leading, trailing or digit-first segments. A module may have 64
message fields instead of 32 (PureModule 11.9 to 13.2 KiB).

pure_app_message_fields takes each variable field's start and size in
the payload, so a host that parsed a request in place passes the
fields' bytes where they are instead of laying them out after the
prefix. The runtime checks them as before: a field past the payload
fails with limit, a text that is not UTF-8 with encoding.

1 files changed, 8 insertions, 1 deletions

diff --git a/prototypes/connections/module.h b/prototypes/connections/module.h
index 3a75fc1..430ccae 100644
--- a/prototypes/connections/module.h
+++ b/prototypes/connections/module.h
@@ -17,7 +17,7 @@ enum {
     PURE_MODULE_STATES = 32, PURE_MODULE_INPUTS = 32, PURE_MODULE_VIEWS = 64,
     PURE_MODULE_HANDLERS = 64, PURE_MODULE_CODE = 65535, PURE_MODULE_STACK = 64,
     PURE_MODULE_NAME = 32, PURE_MODULE_STRINGS = 32768, PURE_MODULE_HEADER = 40,
-    PURE_MODULE_FIELDS = 32, PURE_MODULE_COLLECTIONS = 1, PURE_MODULE_CONSTANTS = 4096,
+    PURE_MODULE_FIELDS = 64, PURE_MODULE_COLLECTIONS = 1, PURE_MODULE_CONSTANTS = 4096,
     PURE_MODULE_CONSTANT_BYTES = 1 << 20, PURE_MODULE_RECORDS = 8, PURE_MODULE_RECORD_FIELDS = 64,
     PURE_RECORD_FIELDS = 16, PURE_MODULE_JOINS = 8, PURE_APP_PENDING = 256
 };
@@ -256,6 +256,13 @@ PureResult pure_app_text(PureApp *, uint32_t input, PureSpan text);
  * pure_app_finish. On return app->revision is the document's revision
  * (deferred: the revision the next save gives it). */
 PureResult pure_app_message(PureApp *, uint32_t input, const char *key, int64_t base, PureSpan payload);
+/* The same, with the variable fields where the host found them: field f
+ * starts at placed[2f] in payload and has placed[2f + 1] bytes (entries of
+ * fixed fields are not read, nor are the variable fields' lengths in the
+ * prefix). A host that parsed a request in place passes the fields' bytes
+ * where they are. */
+PureResult pure_app_message_fields(PureApp *, uint32_t input, const char *key, int64_t base, PureSpan payload,
+                                   const uint32_t *placed);
 /* Visit the reply of the last message in order, without copying, until the
  * next event (deferred: copy it before a later save too). */
 PureResult pure_app_reply(const PureApp *, bool (*visit)(void *, PureSpan), void *context);