Eric Blake <ebl...@redhat.com> writes: > The handling of \ inside QAPI strings was less than ideal, and > really only worked JSON's \/, \\, \", and our extension of \' > (an obvious extension, when you realize we use '' instead of "" > for strings). For other things, like '\n', it resulted in a > literal 'n' instead of a newline. > > Of course, at the moment, we really have no use for escaped > characters, as QAPI has to map to C identifiers, and we currently > support ASCII only for that. But down the road, we may add > support for default values for string parameters to a command > or struct; if that happens, it would be nice to correctly support > all JSON escape sequences, such as \n or \uXXXX. This gets us > closer, by supporting Unicode escapes in the ASCII range. > > Since JSON does not require \OCTAL or \xXX escapes, I did not > add it here, but it would be an easy addition if we desired it. > > Signed-off-by: Eric Blake <ebl...@redhat.com> > --- > > v6: new patch > > --- > scripts/qapi.py | 33 > +++++++++++++++++++++++++++++++- > tests/Makefile | 1 + > tests/qapi-schema/escape-too-big.err | 1 + > tests/qapi-schema/escape-too-big.exit | 1 + > tests/qapi-schema/escape-too-big.json | 3 +++ > tests/qapi-schema/escape-too-big.out | 0 > tests/qapi-schema/escape-too-short.err | 1 + > tests/qapi-schema/escape-too-short.exit | 1 + > tests/qapi-schema/escape-too-short.json | 3 +++ > tests/qapi-schema/escape-too-short.out | 0 > tests/qapi-schema/ident-with-escape.err | 1 - > tests/qapi-schema/ident-with-escape.exit | 2 +- > tests/qapi-schema/ident-with-escape.json | 2 +- > tests/qapi-schema/ident-with-escape.out | 3 +++ > tests/qapi-schema/unicode-str.err | 1 + > tests/qapi-schema/unicode-str.exit | 1 + > tests/qapi-schema/unicode-str.json | 2 ++ > tests/qapi-schema/unicode-str.out | 0 > 18 files changed, 52 insertions(+), 4 deletions(-) > create mode 100644 tests/qapi-schema/escape-too-big.err > create mode 100644 tests/qapi-schema/escape-too-big.exit > create mode 100644 tests/qapi-schema/escape-too-big.json > create mode 100644 tests/qapi-schema/escape-too-big.out > create mode 100644 tests/qapi-schema/escape-too-short.err > create mode 100644 tests/qapi-schema/escape-too-short.exit > create mode 100644 tests/qapi-schema/escape-too-short.json > create mode 100644 tests/qapi-schema/escape-too-short.out > create mode 100644 tests/qapi-schema/unicode-str.err > create mode 100644 tests/qapi-schema/unicode-str.exit > create mode 100644 tests/qapi-schema/unicode-str.json > create mode 100644 tests/qapi-schema/unicode-str.out > > diff --git a/scripts/qapi.py b/scripts/qapi.py > index 60ed34a..853f9a3 100644 > --- a/scripts/qapi.py > +++ b/scripts/qapi.py > @@ -173,7 +173,38 @@ class QAPISchema: > raise QAPISchemaError(self, > 'Missing terminating "\'"') > if esc: > - string += ch > + if ch == 'b': > + string += '\b' > + elif ch == 'f': > + string += '\f' > + elif ch == 'n': > + string += '\n' > + elif ch == 'r': > + string += '\r' > + elif ch == 't': > + string += '\t' > + elif ch == 'u': > + value = 0 > + for x in range(0, 4): > + ch = self.src[self.cursor] > + self.cursor += 1 > + if ch not in "0123456789abcdefABCDEF": > + raise QAPISchemaError(self, > + '\\u escape needs > 4 ' > + 'hex digits') > + value = (value << 4) + int(ch, 16) > + # If Python 2 and 3 didn't disagree so much on > + # how to handle Unicode, then we could allow > + # Unicode string defaults. But most of QAPI is > + # ASCII-only, so we aren't losing much for now. > + if value > 0x7f: > + raise QAPISchemaError(self, > + 'For now, \\u escape ' > + 'only supports values ' > + 'up to \\u007f') > + string += chr(value) > + else: > + string += ch > esc = False > elif ch == "\\": > esc = True
RFC 7159 accepts escapes ["\/bfnrtu], where u is followed by four hexadecimal digits. Our C JSON parser additionally accepts ', see json-lexer.c. This code accepts any character. I'd prefer to make it consistent with our C JSON parser instead. [...]
