These instructions are provided for compatibility purposes and are
used only by old software, in the new code BAS and BASR are preferred.
The difference between the old and new instruction exists only in the
24-bit mode.
In addition, fix BAS polluting high 32 bits of the first operand in
24- and 31-bit addressing modes.
Signed-off-by: Pavel Zbitskiy <pavel.zbitskiy@gmail.com>
Message-Id: <20180821025104.19604-3-pavel.zbitskiy@gmail.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Commit 2c88b098e7 added a call to SPAPR_MACHINE_GET_CLASS(spapr) in
spapr_phb_realize() before we check spapr isn't NULL. This causes QEMU
to crash when starting a non-pseries machine with a sPAPR PHB.
This could be fixed by setting the smc variable after the null check,
but it seems more explicit to use a ternary operator to skip the call
to SPAPR_MACHINE_GET_CLASS() if spapr is NULL, since spapr_phb_realize()
will return immediately in this case.
This was reported by Coverity (CID 1395170 and 1395183).
Fixes: 2c88b098e7
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Introduced in 04d595b300 ("spapr: do not use CPU_FOREACH_REVERSE",
2018-08-23)
Fixes: CID1395181
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
There is no known available OS for ppc around anymore that uses page
sizes below 4k, so it does not make much sense that we keep wasting
our time on building and testing the ppcemb-softmmu target. It has
been deprecated since two releases, and nobody complained, so let's
remove this now.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
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Merge remote-tracking branch 'remotes/juanquintela/tags/check/20180827' into staging
check/next for 20180827
# gpg: Signature made Mon 27 Aug 2018 10:58:51 BST
# gpg: using RSA key F487EF185872D723
# gpg: Good signature from "Juan Quintela <quintela@redhat.com>"
# gpg: aka "Juan Quintela <quintela@trasno.org>"
# Primary key fingerprint: 1899 FF8E DEBF 58CC EE03 4B82 F487 EF18 5872 D723
* remotes/juanquintela/tags/check/20180827:
check: Move wdt_ib700 test to common
check: Move endianess test to common
check: Move VMXNET3 test to common
check: Only test boot-serial when sga is compiled in
check: Only test ivshm when it is compiled in
x86_64-softmmu: Configuration is identical to i386-softmmu
check: Only test usb-xhci-nec when it is compiled in
check: Only test isa-testdev when it is compiled in
configure: We don't want to clean configuration files
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Replace all the trace_vtd_err_*() hooks with the new error_report_once()
since they are similar to trace_vtd_err() - dumping the first error
would be mostly enough, then we have them on by default too.
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180815095328.32414-4-peterx@redhat.com>
[Use "%x" instead of "%" PRIx16 to print uint16_t, whitespace tidied up]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Replace existing trace_vtd_err() with error_report_once() then stderr
will capture something if any of the error happens, meanwhile we don't
suffer from any DDOS. Then remove the trace point. Since at it,
provide more information where proper (now we can pass parameters into
the report function).
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180815095328.32414-3-peterx@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
[Two format strings fixed, whitespace tidied up]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
It is already protected by CONFIG_ISA_TESTDEV in all architectures.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
We protect it with CONFIG_VMXNET3_PCI now, so no need to also put it
on i386.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
This is only for x86* architecture.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
If we ever changed that, just make the things that are different
explicit.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Once there, untangle endianness-test and boot-serial-test.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
---
boot-serial-test don't depend on isa-testdev. Thanks Thomas.
If you don't want to compile everything, you configure
config-devices.mak. And then make clean remove it, and make will
create a default one without your configuration. Fix it by not
removing it on clean target. Remove it instead on distclean.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
---
Remove it instead on distclean.
vhost-user-gpu will share the same code to open a DRM node.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20180713130916.4153-20-marcandre.lureau@redhat.com>
[ kraxel: buildfix: util/drm.o must be CONFIG_OPENGL not CONFIG_LINUX ]
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
There are many error_report()s that can be used in frequently called
functions, especially on IO paths. That can be unideal in that
malicious guest can try to trigger the error tons of time which might
use up the log space on the host (e.g., libvirt can capture the stderr
of QEMU and put it persistently onto disk). In VT-d emulation code, we
have trace_vtd_error() tracer. AFAIU all those places can be replaced
by something like error_report() but trace points are mostly used to
avoid the DDOS attack that mentioned above. However using trace points
mean that errors are not dumped if trace not enabled.
It's not a big deal in most modern server managements since we have
things like logrotate to maintain the logs and make sure the quota is
expected. However it'll still be nice that we just provide another way
to restrict message generations. In most cases, this kind of
error_report()s will only provide valid information on the first message
sent, and all the rest of similar messages will be mostly talking about
the same thing. This patch introduces *_report_once() helpers to allow
a message to be dumped only once during one QEMU process's life cycle.
It will make sure: (1) it's on by deffault, so we can even get something
without turning the trace on and reproducing, and (2) it won't be
affected by DDOS attack.
To implement it, I stole the printk_once() macro from Linux.
CC: Eric Blake <eblake@redhat.com>
CC: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180815095328.32414-2-peterx@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Whitespace adjusted, comments improved]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
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Merge remote-tracking branch 'remotes/amarkovic/tags/mips-queue-aug-2018' into staging
MIPS queue August 2018 v6
# gpg: Signature made Fri 24 Aug 2018 16:52:27 BST
# gpg: using RSA key D4972A8967F75A65
# gpg: Good signature from "Aleksandar Markovic <amarkovic@wavecomp.com>"
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg: There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 8526 FBF1 5DA3 811F 4A01 DD75 D497 2A89 67F7 5A65
* remotes/amarkovic/tags/mips-queue-aug-2018: (45 commits)
target/mips: Add definition of nanoMIPS I7200 CPU
mips_malta: Fix semihosting argument passing for nanoMIPS bare metal
mips_malta: Add setting up GT64120 BARs to the nanoMIPS bootloader
mips_malta: Add basic nanoMIPS boot code for Malta board
elf: Don't check FCR31_NAN2008 bit for nanoMIPS
elf: On elf loading, treat both EM_MIPS and EM_NANOMIPS as legal for MIPS
elf: Relax MIPS' elf_check_arch() to accept EM_NANOMIPS too
elf: Add EM_NANOMIPS value as a valid one for e_machine field
target/mips: Fix ERET/ERETNC behavior related to ADEL exception
target/mips: Add updating BadInstr and BadInstrX for nanoMIPS
target/mips: Add availability control via bit NMS
target/mips: Add emulation of DSP ASE for nanoMIPS - part 6
target/mips: Add emulation of DSP ASE for nanoMIPS - part 5
target/mips: Add emulation of DSP ASE for nanoMIPS - part 4
target/mips: Add emulation of DSP ASE for nanoMIPS - part 3
target/mips: Add emulation of DSP ASE for nanoMIPS - part 2
target/mips: Add emulation of DSP ASE for nanoMIPS - part 1
target/mips: Implement MT ASE support for nanoMIPS
target/mips: Fix pre-nanoMIPS MT ASE instructions availability control
target/mips: Add emulation of nanoMIPS 32-bit branch instructions
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
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>
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>
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>
test_after_failed_device_add() does this:
response = qmp("{'execute': 'device_add',"
" 'arguments': {"
" 'driver': 'virtio-blk-%s',"
" 'drive': 'drive0'"
"}}", qvirtio_get_dev_type());
Wrong. An interpolation specification must be a JSON token, it
doesn't work within JSON string tokens. The code above doesn't use
the value of qvirtio_get_dev_type(), and sends arguments
{"driver": "virtio-blk-%s", "drive": "drive0"}}
The command fails because there is no driver named "virtio-blk-%".
Harmless, since the test wants the command to fail. Screwed up in
commit 2f84a92ec6.
Fix the obvious way. The command now fails because the drive is
empty, like it did before commit 2f84a92ec6.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-55-armbru@redhat.com>
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>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-53-armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-52-armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-51-armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-50-armbru@redhat.com>
Token count and size limits exist to guard against excessive heap
usage. We check them only after we created the token on the heap.
That's assigning a cowboy to the barn to lasso the horse after it has
bolted. Close the barn door instead: check before we create the
token.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-49-armbru@redhat.com>
The last case where qobject_from_json() & friends return null without
setting an error is empty or blank input. Callers:
* block.c's parse_json_protocol() reports "Could not parse the JSON
options". It's marked as a work-around, because it also covered
actual bugs, but they got fixed in the previous few commits.
* qobject_input_visitor_new_str() reports "JSON parse error". Also
marked as work-around. The recent fixes have made this unreachable,
because it currently gets called only for input starting with '{'.
* check-qjson.c's empty_input() and blank_input() demonstrate the
behavior.
* The other callers are not affected since they only pass input with
exactly one JSON value or, in the case of negative tests, one error.
Fail with "Expecting a JSON value" instead of returning null, and
simplify callers.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-48-armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-47-armbru@redhat.com>
json_message_process_token() 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 json_parser_parse(). If a non-empty sequence of tokens remains at
the end of the parse, it's silently ignored. check-qjson.c cases
unterminated_array(), unterminated_array_comma(), unterminated_dict(),
unterminated_dict_comma() demonstrate this bug.
Fix as follows. Introduce a JSON_END_OF_INPUT token. When the
streamer receives it, it feeds the accumulated tokens to
json_parser_parse().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-46-armbru@redhat.com>
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>
qobject_from_json() & friends use the consume_json() callback to
receive either a value or an error from the parser.
When they are fed a string that contains more than either one JSON
value or one JSON syntax error, consume_json() gets called multiple
times.
When the last call receives a value, qobject_from_json() returns that
value. Any other values are leaked.
When any call receives an error, qobject_from_json() sets the first
error received. Any other errors are thrown away.
When values follow errors, qobject_from_json() returns both a value
and sets an error. That's bad. Impact:
* block.c's parse_json_protocol() ignores and leaks the value. It's
used to to parse pseudo-filenames starting with "json:". The
pseudo-filenames can come from the user or from image meta-data such
as a QCOW2 image's backing file name.
* vl.c's parse_display_qapi() ignores and leaks the error. It's used
to parse the argument of command line option -display.
* vl.c's main() case QEMU_OPTION_blockdev ignores the error and leaves
it in @err. main() will then pass a pointer to a non-null Error *
to net_init_clients(), which is forbidden. It can lead to assertion
failure or other misbehavior.
* check-qjson.c's multiple_values() demonstrates the badness.
* The other callers are not affected since they only pass strings with
exactly one JSON value or, in the case of negative tests, one
error.
The impact on the _nofail() functions is relatively harmless. They
abort when any call receives an error. Else they return the last
value, and leak the others, if any.
Fix consume_json() as follows. On the first call, save value and
error as before. On subsequent calls, if any, don't save them. If
the first call saved a value, the next call, if any, replaces the
value by an "Expecting at most one JSON value" error. Take care not
to leak values or errors that aren't saved.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-44-armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-43-armbru@redhat.com>
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>
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>
The callback to consume JSON values takes QObject *json, Error *err.
If both are null, the callback is supposed to make up an error by
itself. This sucks.
qjson.c's consume_json() neglects to do so, which makes
qobject_from_json() null instead of failing. I consider that a bug.
The culprit is json_message_process_token(): it passes two null
pointers when it runs into a lexical error or a limit violation. Fix
it to pass a proper Error object then. Update the callbacks:
* monitor.c's handle_qmp_command(): the code to make up an error is
now dead, drop it.
* qga/main.c's process_event(): lumps the "both null" case together
with the "not a JSON object" case. The former is now gone. The
error message "Invalid JSON syntax" is misleading for the latter.
Improve it to "Input must be a JSON object".
* qobject/qjson.c's consume_json(): no update; check-qjson
demonstrates qobject_from_json() now sets an error on lexical
errors, but still doesn't on some other errors.
* tests/libqtest.c's qmp_response(): the Error object is now reliable,
so use it to improve the error message.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-40-armbru@redhat.com>
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>
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>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180823164025.12553-37-armbru@redhat.com>
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>
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>
