Commit Graph

60 Commits

Author SHA1 Message Date
Marc-André Lureau 9edc6313da Replace GCC_FMT_ATTR with G_GNUC_PRINTF
One less qemu-specific macro. It also helps to make some headers/units
only depend on glib, and thus moved in standalone projects eventually.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
2022-03-22 14:40:51 +04:00
Zhang Han 5086c9973a qobject: open brace '{' following struct go on the same line
Put open brace '{' on the same line of struct.

Signed-off-by: Zhang Han <zhanghan64@huawei.com>
Message-Id: <20201228071129.24563-2-zhanghan64@huawei.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-02-04 13:20:28 +01:00
Markus Armbruster 68af4cc121 json: Use GString instead of QString to accumulate strings
QString supports modifying its string, but it's quite limited: you can
only append.  The remaining callers use it for building an initial
string, never for modifying it later.

Change parse_string() to do build the initial string with GString.
This is another step towards making QString immutable.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201211171152.146877-18-armbru@redhat.com>
2020-12-19 10:39:23 +01:00
Alex Chen 922d42bb0d json: Fix a memleak in parse_pair()
In qobject_type(), NULL is returned when the 'QObject' returned from parse_value() is not of QString type,
and this 'QObject' memory will leaked.
So we need to first cache the 'QObject' returned from parse_value(), and finally
free 'QObject' memory at the end of the function.
Also, we add a testcast about invalid dict key.

The memleak stack is as follows:
Direct leak of 32 byte(s) in 1 object(s) allocated from:
    #0 0xfffe4b3c34fb in __interceptor_malloc (/lib64/libasan.so.4+0xd34fb)
    #1 0xfffe4ae48aa3 in g_malloc (/lib64/libglib-2.0.so.0+0x58aa3)
    #2 0xaaab3557d9f7 in qnum_from_int qemu/qobject/qnum.c:25
    #3 0xaaab35584d23 in parse_literal qemu/qobject/json-parser.c:511
    #4 0xaaab35584d23 in parse_value qemu/qobject/json-parser.c:554
    #5 0xaaab35583d77 in parse_pair qemu/qobject/json-parser.c:270
    #6 0xaaab355845db in parse_object qemu/qobject/json-parser.c:327
    #7 0xaaab355845db in parse_value qemu/qobject/json-parser.c:546
    #8 0xaaab35585b1b in json_parser_parse qemu/qobject/json-parser.c:580
    #9 0xaaab35583703 in json_message_process_token qemu/qobject/json-streamer.c:92
    #10 0xaaab355ddccf in json_lexer_feed_char qemu/qobject/json-lexer.c:313
    #11 0xaaab355de0eb in json_lexer_feed qemu/qobject/json-lexer.c:350
    #12 0xaaab354aff67 in tcp_chr_read qemu/chardev/char-socket.c:525
    #13 0xfffe4ae429db in g_main_context_dispatch (/lib64/libglib-2.0.so.0+0x529db)
    #14 0xfffe4ae42d8f  (/lib64/libglib-2.0.so.0+0x52d8f)
    #15 0xfffe4ae430df in g_main_loop_run (/lib64/libglib-2.0.so.0+0x530df)
    #16 0xaaab34d70bff in iothread_run qemu/iothread.c:82
    #17 0xaaab3559d71b in qemu_thread_start qemu/util/qemu-thread-posix.c:519

Fixes: 532fb53284 ("qapi: Make more of qobject_to()")
Reported-by: Euler Robot <euler.robot@huawei.com>
Signed-off-by: Alex Chen <alex.chen@huawei.com>
Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201113145525.85151-1-alex.chen@huawei.com>
[Commit message tweaked]
2020-11-17 15:39:53 +01:00
Philippe Mathieu-Daudé 6f0dd6c5d2 json: Move switch 'fall through' comment to correct place
Reported by GCC9 when building with CFLAG -Wimplicit-fallthrough=2:

  qobject/json-parser.c: In function ‘parse_literal’:
  qobject/json-parser.c:492:24: error: this statement may fall through [-Werror=implicit-fallthrough=]
    492 |     case JSON_INTEGER: {
        |                        ^
  qobject/json-parser.c:524:5: note: here
    524 |     case JSON_FLOAT:
        |     ^~~~

Correctly place the 'fall through' comment.

Reported-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20190719131425.10835-2-philmd@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2019-08-21 10:54:31 +02:00
Markus Armbruster 856dfd8a03 qemu-common: Move qemu_isalnum() etc. to qemu/ctype.h
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190523143508.25387-3-armbru@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2019-06-11 20:22:09 +02:00
Christophe Fergeau bbc0586ced json: Fix % handling when not interpolating
Commit 8bca4613 added support for %% in json strings when interpolating,
but in doing so broke handling of % when not interpolating.

When parse_string() is fed a string token containing '%', it skips the
'%' regardless of ctxt->ap, i.e. even it's not interpolating.  If the
'%' is the string's last character, it fails an assertion.  Else, it
"merely" swallows the '%'.

Fix parse_string() to handle '%' specially only when interpolating.

To gauge the bug's impact, let's review non-interpolating users of this
parser, i.e. code passing NULL context to json_message_parser_init():

* tests/check-qjson.c, tests/test-qobject-input-visitor.c,
  tests/test-visitor-serialization.c

  Plenty of tests, but we still failed to cover the buggy case.

* monitor.c: QMP input

* qga/main.c: QGA input

* qobject_from_json():

  - qobject-input-visitor.c: JSON command line option arguments of
    -display and -blockdev

    Reproducer: -blockdev '{"%"}'

  - block.c: JSON pseudo-filenames starting with "json:"

    Reproducer: https://bugzilla.redhat.com/show_bug.cgi?id=1668244#c3

  - block/rbd.c: JSON key pairs

    Pseudo-filenames starting with "rbd:".

Command line, QMP and QGA input are trusted.

Filenames are trusted when they come from command line, QMP or HMP.
They are untrusted when they come from from image file headers.
Example: QCOW2 backing file name.  Note that this is *not* the security
boundary between host and guest.  It's the boundary between host and an
image file from an untrusted source.

Neither failing an assertion nor skipping a character in a filename of
your choice looks exploitable.  Note that we don't support compiling
with NDEBUG.

Fixes: 8bca4613e6
Cc: qemu-stable@nongnu.org
Signed-off-by: Christophe Fergeau <cfergeau@redhat.com>
Message-Id: <20190102140535.11512-1-cfergeau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
[Commit message extended to discuss impact]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2019-01-24 15:20:59 +01:00
Markus Armbruster 00382fa851 json: Fix to reject duplicate object member names
The JSON parser happily accepts duplicate object member names.  The
last value wins.  Reproducer #1:

    $ qemu-system-x86_64 -qmp stdio
    {"QMP": {"version": {"qemu": {"micro": 93, "minor": 0, "major": 3},
    "package": "v3.1.0-rc3-7-g87a45d86ed"}, "capabilities": []}}
    {'execute':'qmp_capabilities'}
    {"return": {}}
    {'execute':'blockdev-add','arguments':{'driver':'null-co',
     'node-name':'foo','node-name':'bar'}}
    {"return": {}}
    {'execute':'query-named-block-nodes'}
    {"return": [{ [...] "node-name": "bar" [...] }]}

Reproducer #2 is iotest 229.

Fix the parser to reject duplicates, and fix iotest 229 not to use
them.

Reported-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20181206121743.20762-1-armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
[Trailing whitespace tidied up]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-12-13 19:20:11 +01:00
Markus Armbruster 37aded92c2 json: Update references to RFC 7159 to RFC 8259
RFC 8259 (December 2017) obsoletes RFC 7159 (March 2014).

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180823164025.12553-59-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2018-08-24 20:27:14 +02:00
Markus Armbruster 8bca4613e6 json: Support %% in JSON strings when interpolating
The previous commit makes JSON strings containing '%' awkward to
express in templates: you'd have to mask the '%' with an Unicode
escape \u0025.  No template currently contains such JSON strings.
Support the printf conversion specification %% in JSON strings as a
convenience anyway, because it's trivially easy to do.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-58-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster 16a4859921 json: Improve safety of qobject_from_jsonf_nofail() & friends
The JSON parser optionally supports interpolation.  This is used to
build QObjects by parsing string templates.  The templates are C
literals, so parse errors (such as invalid interpolation
specifications) are actually programming errors.  Consequently, the
functions providing parsing with interpolation
(qobject_from_jsonf_nofail(), qobject_from_vjsonf_nofail(),
qdict_from_jsonf_nofail(), qdict_from_vjsonf_nofail()) pass
&error_abort to the parser.

However, there's another, more dangerous kind of programming error:
since we use va_arg() to get the value to interpolate, behavior is
undefined when the variable argument isn't consistent with the
interpolation specification.

The same problem exists with printf()-like functions, and the solution
is to have the compiler check consistency.  This is what
GCC_FMT_ATTR() is about.

To enable this type checking for interpolation as well, we carefully
chose our interpolation specifications to match printf conversion
specifications, and decorate functions parsing templates with
GCC_FMT_ATTR().

Note that this only protects against undefined behavior due to type
errors.  It can't protect against use of invalid interpolation
specifications that happen to be valid printf conversion
specifications.

However, there's still a gaping hole in the type checking: GCC
recognizes '%' as start of printf conversion specification anywhere in
the template, but the parser recognizes it only outside JSON strings.
For instance, if someone were to pass a "{ '%s': %d }" template, GCC
would require a char * and an int argument, but the parser would
va_arg() only an int argument, resulting in undefined behavior.

Avoid undefined behavior by catching the programming error at run
time: have the parser recognize and reject '%' in JSON strings.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-57-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster ada74c3ba1 json: Keep interpolation state in JSONParserContext
The recursive descent parser passes along a pointer to
JSONParserContext.  It additionally passes a pointer to interpolation
state (a va_alist *) as needed to reach its consumer
parse_interpolation().

Stuffing the latter pointer into JSONParserContext saves us the
trouble of passing it along, so do that.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-56-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster 86cdf9ec8d json: Clean up headers
The JSON parser has three public headers, json-lexer.h, json-parser.h,
json-streamer.h.  They all contain stuff that is of no interest
outside qobject/json-*.c.

Collect the public interface in include/qapi/qmp/json-parser.h, and
everything else in qobject/json-parser-int.h.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-54-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster abe7c2067c json: Make JSONToken opaque outside json-parser.c
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-52-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster a2731e08ee json: Unbox tokens queue in JSONMessageParser
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-51-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster 5d50113cf6 json: Assert json_parser_parse() consumes all tokens on success
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-47-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster e06d008ac8 json: Fix latent parser aborts at end of input
json-parser.c carefully reports end of input like this:

    token = parser_context_pop_token(ctxt);
    if (token == NULL) {
        parse_error(ctxt, NULL, "premature EOI");
        goto out;
    }

Except parser_context_pop_token() can't return null, it fails its
assertion instead.  Same for parser_context_peek_token().  Broken in
commit 65c0f1e955, and faithfully preserved in commit 95385fe9ac.
Only a latent bug, because the streamer throws away any input that
could trigger it.

Drop the assertions, so we can fix the streamer in the next commit.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-45-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster 53a0d616fe json: Replace %I64d, %I64u by %PRId64, %PRIu64
Support for %I64d got added in commit 2c0d4b36e7 "json: fix PRId64 on
Win32".  We had to hard-code I64d because we used the lexer's finite
state machine to check interpolations.  No more, so clean this up.

Additional conversion specifications would be easy enough to implement
when needed.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-42-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster f7617d45d4 json: Leave rejecting invalid interpolation to parser
Both lexer and parser reject invalid interpolation specifications.
The parser's check is useless.

The lexer ends the token right after the first bad character.  This
tends to lead to suboptimal error reporting.  For instance, input

    [ %04d ]

produces the tokens

    JSON_LSQUARE  [
    JSON_ERROR    %0
    JSON_INTEGER  4
    JSON_KEYWORD  d
    JSON_RSQUARE  ]

The parser then yields an error, an object and two more errors:

    error: Invalid JSON syntax
    object: 4
    error: JSON parse error, invalid keyword
    error: JSON parse error, expecting value

Dumb down the lexer to accept [A-Za-z0-9]*.  The parser's check is now
used.  Emit a proper error there.

The lexer now produces

    JSON_LSQUARE  [
    JSON_INTERP   %04d
    JSON_RSQUARE  ]

and the parser reports just

    JSON parse error, invalid interpolation '%04d'

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-41-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster 2cbd15aa6f json: Treat unwanted interpolation as lexical error
The JSON parser optionally supports interpolation.  The lexer
recognizes interpolation tokens unconditionally.  The parser rejects
them when interpolation is disabled, in parse_interpolation().
However, it neglects to set an error then, which can make
json_parser_parse() fail without setting an error.

Move the check for unwanted interpolation from the parser's
parse_interpolation() into the lexer's finite state machine.  When
interpolation is disabled, '%' is now handled like any other
unexpected character.

The next commit will improve how such lexical errors are handled.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-39-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster 61030280ca json: Rename token JSON_ESCAPE & friends to JSON_INTERP
The JSON parser optionally supports interpolation.  The code calls it
"escape".  Awkward, because it uses the same term for escape sequences
within strings.  The latter usage is consistent with RFC 8259 "The
JavaScript Object Notation (JSON) Data Interchange Format" and ISO C.
Call the former "interpolation" instead.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-38-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster ff281a272f json: Don't pass null @tokens to json_parser_parse()
json_parser_parse() normally returns the QObject on success.  Except
it returns null when its @tokens argument is null.

Its only caller json_message_process_token() passes null @tokens when
emitting a lexical error.  The call is a rather opaque way to say json
= NULL then.

Simplify matters by lifting the assignment to json out of the emit
path: initialize json to null, set it to the value of
json_parser_parse() when there's no lexical error.  Drop the special
case from json_parser_parse().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-36-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster 62815d85ae json: Redesign the callback to consume JSON values
The classical way to structure parser and lexer is to have the client
call the parser to get an abstract syntax tree, the parser call the
lexer to get the next token, and the lexer call some function to get
input characters.

Another way to structure them would be to have the client feed
characters to the lexer, the lexer feed tokens to the parser, and the
parser feed abstract syntax trees to some callback provided by the
client.  This way is more easily integrated into an event loop that
dispatches input characters as they arrive.

Our JSON parser is kind of between the two.  The lexer feeds tokens to
a "streamer" instead of a real parser.  The streamer accumulates
tokens until it got the sequence of tokens that comprise a single JSON
value (it counts curly braces and square brackets to decide).  It
feeds those token sequences to a callback provided by the client.  The
callback passes each token sequence to the parser, and gets back an
abstract syntax tree.

I figure it was done that way to make a straightforward recursive
descent parser possible.  "Get next token" becomes "pop the first
token off the token sequence".  Drawback: we need to store a complete
token sequence.  Each token eats 13 + input characters + malloc
overhead bytes.

Observations:

1. This is not the only way to use recursive descent.  If we replaced
   "get next token" by a coroutine yield, we could do without a
   streamer.

2. The lexer reports errors by passing a JSON_ERROR token to the
   streamer.  This communicates the offending input characters and
   their location, but no more.

3. The streamer reports errors by passing a null token sequence to the
   callback.  The (already poor) lexical error information is thrown
   away.

4. Having the callback receive a token sequence duplicates the code to
   convert token sequence to abstract syntax tree in every callback.

5. Known bug: the streamer silently drops incomplete token sequences.

This commit rectifies 4. by lifting the call of the parser from the
callbacks into the streamer.  Later commits will address 3. and 5.

The lifting removes a bug from qjson.c's parse_json(): it passed a
pointer to a non-null Error * in certain cases, as demonstrated by
check-qjson.c.

json_parser_parse() is now unused.  It's a stupid wrapper around
json_parser_parse_err().  Drop it, and rename json_parser_parse_err()
to json_parser_parse().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-35-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Marc-André Lureau e8b19d7d73 json-parser: simplify and avoid JSONParserContext allocation
parser_context_new/free() are only used from json_parser_parse(). We
can fold the code there and avoid an allocation altogether.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20180719184111.5129-9-marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180823164025.12553-33-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster dc45a07c36 json: Fix \uXXXX for surrogate pairs
The JSON parser treats each half of a surrogate pair as unpaired
surrogate.  Fix it to recognize surrogate pairs.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-30-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster 46a628b139 json: Reject invalid \uXXXX, fix \u0000
The JSON parser translates invalid \uXXXX to garbage instead of
rejecting it, and swallows \u0000.

Fix by using mod_utf8_encode() instead of flawed wchar_to_utf8().

Valid surrogate pairs are now differently broken: they're rejected
instead of translated to garbage.  The next commit will fix them.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-29-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster de6decfe8e json: Simplify parse_string()
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-28-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster b2da4a4d75 json: Leave rejecting invalid escape sequences to parser
Both lexer and parser reject invalid escape sequences in strings.  The
parser's check is useless.

The lexer ends the token right after the first non-well-formed byte.
This tends to lead to suboptimal error reporting.  For instance, input

    {"abc\@ijk": 1}

produces the tokens

    JSON_LCURLY   {
    JSON_ERROR    "abc\@
    JSON_KEYWORD  ijk
    JSON_ERROR   ": 1}\n

The parser then reports three errors

    Invalid JSON syntax
    JSON parse error, invalid keyword 'ijk'
    Invalid JSON syntax

before it recovers at the newline.

Drop the lexer's escape sequence checking, and make it accept the same
characters after backslash it accepts elsewhere in strings.  It now
produces

    JSON_LCURLY   {
    JSON_STRING   "abc\@ijk"
    JSON_COLON    :
    JSON_INTEGER  1
    JSON_RCURLY

and the parser reports just

    JSON parse error, invalid escape sequence in string

While there, fix parse_string()'s inaccurate function comment.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-27-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster 4b1c0cd7c7 json: Accept overlong \xC0\x80 as U+0000 ("modified UTF-8")
Since the JSON grammer doesn't accept U+0000 anywhere, this merely
exchanges one kind of parse error for another.  It's purely for
consistency with qobject_to_json(), which accepts \xC0\x80 (see commit
e2ec3f9768).

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-26-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster 574bf16ff1 json: Report first rather than last parse error
Quiz time!  When a parser reports multiple errors, but the user gets
to see just one, which one is (on average) the least useful one?

Yes, you're right, it's the last one!  You're clearly familiar with
compilers.

Which one does QEMU report?

Right again, the last one!  You're clearly familiar with QEMU.

Reproducer: feeding

    {"abc\xC2ijk": 1}\n

to QMP produces

    {"error": {"class": "GenericError", "desc": "JSON parse error, key is not a string in object"}}

Report the first error instead.  The reproducer now produces

    {"error": {"class": "GenericError", "desc": "JSON parse error, invalid UTF-8 sequence in string"}}

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-24-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster e59f39d403 json: Reject invalid UTF-8 sequences
We reject bytes that can't occur in valid UTF-8 (\xC0..\xC1,
\xF5..\xFF in the lexer.  That's insufficient; there's plenty of
invalid UTF-8 not containing these bytes, as demonstrated by
check-qjson:

* Malformed sequences

  - Unexpected continuation bytes

  - Missing continuation bytes after start bytes other than
    \xC0..\xC1, \xF5..\xFD.

* Overlong sequences with start bytes other than \xC0..\xC1,
  \xF5..\xFD.

* Invalid code points

Fixing this in the lexer would be bothersome.  Fixing it in the parser
is straightforward, so do that.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-23-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Markus Armbruster 00ea57fadc json: Tighten and simplify qstring_from_escaped_str()'s loop
Simplify loop control, and assert that the string ends with the
appropriate quote (the lexer ensures it does).

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-21-armbru@redhat.com>
2018-08-24 20:26:37 +02:00
Marc-André Lureau cb3e7f08ae qobject: Replace qobject_incref/QINCREF qobject_decref/QDECREF
Now that we can safely call QOBJECT() on QObject * as well as its
subtypes, we can have macros qobject_ref() / qobject_unref() that work
everywhere instead of having to use QINCREF() / QDECREF() for QObject
and qobject_incref() / qobject_decref() for its subtypes.

The replacement is mechanical, except I broke a long line, and added a
cast in monitor_qmp_cleanup_req_queue_locked().  Unlike
qobject_decref(), qobject_unref() doesn't accept void *.

Note that the new macros evaluate their argument exactly once, thus no
need to shout them.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180419150145.24795-4-marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Rebased, semantic conflict resolved, commit message improved]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-05-04 08:27:53 +02:00
Max Reitz 532fb53284 qapi: Make more of qobject_to()
This patch reworks some places which use either qobject_type() checks
plus qobject_to(), where the latter alone is sufficient, or NULL checks
plus qobject_type() checks where we can simply do a qobject_to() != NULL
check.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-Id: <20180224154033.29559-6-mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: rebase to qobject_to() parameter ordering]
Signed-off-by: Eric Blake <eblake@redhat.com>
2018-03-19 14:58:36 -05:00
Max Reitz 7dc847ebba qapi: Replace qobject_to_X(o) by qobject_to(X, o)
This patch was generated using the following Coccinelle script:

@@
expression Obj;
@@
(
- qobject_to_qnum(Obj)
+ qobject_to(QNum, Obj)
|
- qobject_to_qstring(Obj)
+ qobject_to(QString, Obj)
|
- qobject_to_qdict(Obj)
+ qobject_to(QDict, Obj)
|
- qobject_to_qlist(Obj)
+ qobject_to(QList, Obj)
|
- qobject_to_qbool(Obj)
+ qobject_to(QBool, Obj)
)

and a bit of manual fix-up for overly long lines and three places in
tests/check-qjson.c that Coccinelle did not find.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-Id: <20180224154033.29559-4-mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: swap order from qobject_to(o, X), rebase to master, also a fix
to latent false-positive compiler complaint about hw/i386/acpi-build.c]
Signed-off-by: Eric Blake <eblake@redhat.com>
2018-03-19 14:58:36 -05:00
Markus Armbruster 452fcdbc49 Include qapi/qmp/qdict.h exactly where needed
This cleanup makes the number of objects depending on qapi/qmp/qdict.h
drop from 4550 (out of 4743) to 368 in my "build everything" tree.
For qapi/qmp/qobject.h, the number drops from 4552 to 390.

While there, separate #include from file comment with a blank line.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-13-armbru@redhat.com>
2018-02-09 13:52:15 +01:00
Markus Armbruster 47e6b297e7 Include qapi/qmp/qlist.h exactly where needed
This cleanup makes the number of objects depending on qapi/qmp/qlist.h
drop from 4551 (out of 4743) to 16 in my "build everything" tree.

While there, separate #include from file comment with a blank line.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-12-armbru@redhat.com>
2018-02-09 13:52:15 +01:00
Markus Armbruster 15280c360e qdict qlist: Make most helper macros functions
The macro expansions of qdict_put_TYPE() and qlist_append_TYPE() need
qbool.h, qnull.h, qnum.h and qstring.h to compile.  We include qnull.h
and qnum.h in the headers, but not qbool.h and qstring.h.  Works,
because we include those wherever the macros get used.

Open-coding these helpers is of dubious value.  Turn them into
functions and drop the includes from the headers.

This cleanup makes the number of objects depending on qapi/qmp/qnum.h
from 4551 (out of 4743) to 46 in my "build everything" tree.  For
qapi/qmp/qnull.h, the number drops from 4552 to 21.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-10-armbru@redhat.com>
2018-02-09 13:52:15 +01:00
Markus Armbruster 6b67395762 Eliminate qapi/qmp/types.h
qapi/qmp/types.h is a convenience header to include a number of
qapi/qmp/ headers.  Since we rarely need all of the headers
qapi/qmp/types.h includes, we bypass it most of the time.  Most of the
places that use it don't need all the headers, either.

Include the necessary headers directly, and drop qapi/qmp/types.h.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-9-armbru@redhat.com>
2018-02-09 13:52:15 +01:00
Markus Armbruster 006ca09f30 qapi: Separate type QNull from QObject
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
2017-07-24 13:35:11 +02:00
Marc-André Lureau 2bc7cfea09 json: learn to parse uint64 numbers
Switch strtoll() usage to qemu_strtoi64() helper while at it.

Add a few tests for large numbers.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20170607163635.17635-11-marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2017-06-20 14:31:31 +02:00
Marc-André Lureau 01b2ffcedd qapi: merge QInt and QFloat in QNum
We would like to use a same QObject type to represent numbers, whether
they are int, uint, or floats. Getters will allow some compatibility
between the various types if the number fits other representations.

Add a few more tests while at it.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20170607163635.17635-7-marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[parse_stats_intervals() simplified a bit, comment in
test_visitor_in_int_overflow() tidied up, suppress bogus warnings]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2017-06-20 14:31:31 +02:00
Eric Blake c7eb39cbd4 qapi: Improve use of qmp/types.h
'qjson.h' is not a QObject subtype; include this file directly in
.c files that are using it, rather than abusing qmp/types.h for
that purpose.

Meanwhile, for files that include a list of individual QObject
subtypes, it's easier to just use qmp/types.h for that purpose.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1465490926-28625-2-git-send-email-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-07-06 10:52:03 +02:00
Veronia Bahaa f348b6d1a5 util: move declarations out of qemu-common.h
Move declarations out of qemu-common.h for functions declared in
utils/ files: e.g. include/qemu/path.h for utils/path.c.
Move inline functions out of qemu-common.h and into new files (e.g.
include/qemu/bcd.h)

Signed-off-by: Veronia Bahaa <veroniabahaa@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:17 +01:00
Markus Armbruster da34e65cb4 include/qemu/osdep.h: Don't include qapi/error.h
Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the
Error typedef.  Since then, we've moved to include qemu/osdep.h
everywhere.  Its file comment explains: "To avoid getting into
possible circular include dependencies, this file should not include
any other QEMU headers, with the exceptions of config-host.h,
compiler.h, os-posix.h and os-win32.h, all of which are doing a
similar job to this file and are under similar constraints."
qapi/error.h doesn't do a similar job, and it doesn't adhere to
similar constraints: it includes qapi-types.h.  That's in excess of
100KiB of crap most .c files don't actually need.

Add the typedef to qemu/typedefs.h, and include that instead of
qapi/error.h.  Include qapi/error.h in .c files that need it and don't
get it now.  Include qapi-types.h in qom/object.h for uint16List.

Update scripts/clean-includes accordingly.  Update it further to match
reality: replace config.h by config-target.h, add sysemu/os-posix.h,
sysemu/os-win32.h.  Update the list of includes in the qemu/osdep.h
comment quoted above similarly.

This reduces the number of objects depending on qapi/error.h from "all
of them" to less than a third.  Unfortunately, the number depending on
qapi-types.h shrinks only a little.  More work is needed for that one.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
[Fix compilation without the spice devel packages. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:15 +01:00
Eric Blake 6e8e5cb9aa qobject: Document more shortcomings in our number handling
We've already documented that our JSON parsing is locale dependent;
but we should also document that our JSON output has the same
problem.  Additionally, JSON requires finite values (you have to
upgrade to JSON5 to get support for Inf or NaN), and our output
truncates floating point numbers to the point of losing significant
precision that could cause the receiver to read a different value.

Sadly, this series is not going to be the one that addresses these
problems.

Fix some trailing whitespace I noticed in the vicinity.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1454075341-13658-2-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-08 17:29:54 +01:00
Peter Maydell f2ad72b30e qobject: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1454089805-5470-12-git-send-email-peter.maydell@linaro.org
2016-02-04 17:41:30 +00:00
Paolo Bonzini 9bada89711 qjson: surprise, allocating 6 QObjects per token is expensive
Replace the contents of the tokens GQueue with a simple struct.  This cuts
the amount of memory allocated by tests/check-qjson from ~500MB to ~20MB,
and the execution time from 600ms to 80ms on my laptop.  Still a lot (some
could be saved by using an intrusive list, such as QSIMPLEQ, instead of
the GQueue), but the savings are already massive and the right thing to
do would probably be to get rid of json-streamer completely.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1448300659-23559-5-git-send-email-pbonzini@redhat.com>
[Straightforwardly rebased on my patches]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-11-26 10:07:07 +01:00
Paolo Bonzini 95385fe9ac qjson: store tokens in a GQueue
Even though we still have the "streamer" concept, the tokens can now
be deleted as they are read.  While doing so convert from QList to
GQueue, since the next step will make tokens not a QObject and we
will have to do the conversion anyway.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1448300659-23559-4-git-send-email-pbonzini@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-11-26 10:07:07 +01:00
Markus Armbruster d538b25543 qjson: Convert to parser to recursive descent
We backtrack in parse_value(), even though JSON is LL(1) and thus can
be parsed by straightforward recursive descent.  Do exactly that.

Based on an almost-correct patch from Paolo Bonzini.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1448486613-17634-10-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-11-26 10:06:57 +01:00