To support programmatic JSON assembly while keeping the code that generates it
readable, this patch introduces a simple JSON writer. It emits JSON serially
into a buffer in memory.
The nice thing about this writer is its simplicity and low memory overhead.
Unlike the QMP JSON writer, this one does not need to spawn QObjects for every
element it wants to represent.
This is a prerequisite for the migration stream format description generator.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
The monitor does not pretty-print JSON output, so that everything
will be on a single line reply. When JSON docs get large this is
quite unpleasant to read. For the future command line capabilities
query ability, huge JSON docs will be available. This needs the
ability to pretty-print.
This introduces a new API qobject_to_json_pretty() that does
a minimal indentation of list and dict members. As an example,
this makes
{"QMP": {"version": {"micro": 50, "minor": 12, "package": "", "major": 0}, "capabilities": []}}
Output as
{
"QMP": {
"version": {
"micro": 50,
"minor": 12,
"package": "",
"major": 0
},
"capabilities": [
]
}
}
NB: this is not turned on for the QMP monitor.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Add an assert() to qobject_from_jsonf() to assure that the returned
QObject is not NULL. Currently this is duplicated in the callers.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Markus Armbruster pointed out:
JSON requires control characters in strings to be escaped. RFC 4627
section 2.5:
A string begins and ends with quotation marks. All Unicode
characters may be placed within the quotation marks except for the
characters that must be escaped: quotation mark, reverse solidus, and
the control characters (U+0000 through U+001F).
We've been quoting the special escape sequences that JSON defines but we
haven't been encoding the full control character range. This patch fixes that.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
QError is a high-level data type which represents an exception
in QEMU, it stores the following error information:
- class Error class name (eg. "ServiceUnavailable")
- description A detailed error description, which can contain
references to run-time error data
- filename The file name of where the error occurred
- line number The exact line number of the error
- function The function name of where the error occurred
- run-time data Any run-time error data
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
It accepts a va_list and will be used by QError. Also simplifies
the code a little, as the other qobject_from_() functions can
use it.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
