qemu/qobject
Markus Armbruster 0f07a5d5f1 json: Nicer recovery from lexical errors
When the lexer chokes on an input character, it consumes the
character, emits a JSON error token, and enters its start state.  This
can lead to suboptimal error recovery.  For instance, input

    0123 ,

produces the tokens

    JSON_ERROR    01
    JSON_INTEGER  23
    JSON_COMMA    ,

Make the lexer skip characters after a lexical error until a
structural character ('[', ']', '{', '}', ':', ','), an ASCII control
character, or '\xFE', or '\xFF'.

Note that we must not skip ASCII control characters, '\xFE', '\xFF',
because those are documented to force the JSON parser into known-good
state, by docs/interop/qmp-spec.txt.

The lexer now produces

    JSON_ERROR    01
    JSON_COMMA    ,

Update qmp-test for the nicer error recovery: QMP now reports just one
error for input %p instead of two.  Also drop the newline after %p; it
was needed to tease out the second error.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180831075841.13363-5-armbru@redhat.com>
[Conflict with commit ebb4d82d88 resolved]
2018-09-24 18:08:07 +02:00
..
block-qdict.c qdict: Make qdict_extract_subqdict() accept dst = NULL 2018-08-15 12:50:39 +02:00
json-lexer.c json: Nicer recovery from lexical errors 2018-09-24 18:08:07 +02:00
json-parser-int.h json: Make lexer's "character consumed" logic less confusing 2018-09-24 18:06:09 +02:00
json-parser.c json: Update references to RFC 7159 to RFC 8259 2018-08-24 20:27:14 +02:00
json-streamer.c json: Clean up headers 2018-08-24 20:26:37 +02:00
Makefile.objs qobject: Move block-specific qdict code to block-qdict.c 2018-06-15 14:49:44 +02:00
qbool.c qobject: Drop superfluous includes of qemu-common.h 2018-08-24 20:26:37 +02:00
qdict.c qobject: Move block-specific qdict code to block-qdict.c 2018-06-15 14:49:44 +02:00
qjson.c json: Clean up headers 2018-08-24 20:26:37 +02:00
qlist.c qobject: Drop superfluous includes of qemu-common.h 2018-08-24 20:26:37 +02:00
qlit.c qapi: Replace qobject_to_X(o) by qobject_to(X, o) 2018-03-19 14:58:36 -05:00
qnull.c qobject: Drop superfluous includes of qemu-common.h 2018-08-24 20:26:37 +02:00
qnum.c qobject: Drop superfluous includes of qemu-common.h 2018-08-24 20:26:37 +02:00
qobject.c qobject: Drop superfluous includes of qemu-common.h 2018-08-24 20:26:37 +02:00
qstring.c qobject: Drop superfluous includes of qemu-common.h 2018-08-24 20:26:37 +02:00