qapi: Drop support for escape sequences other than \\

Since the previous commit restricted strings to printable ASCII,
\uXXXX's only use is obfuscation.  Drop it.

This leaves \\, \/, \', and \".  Since QAPI schema strings are all
names, and names are restricted to ASCII letters, digits, hyphen, and
underscore, none of them is useful.

The latter three have no test coverage.  Drop them.

Keep \\ to avoid (more) gratuitous incompatibility with JSON.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20190913201349.24332-8-armbru@redhat.com>

19 files changed, 7 insertions, 60 deletions

diff --git a/scripts/qapi/common.py b/scripts/qapi/common.py
index 539b50f..0fb1d19 100644
--- a/scripts/qapi/common.py
+++ b/scripts/qapi/common.py
@@ -524,29 +524,9 @@ class QAPISchemaParser(object):
                     if ch == '\n':
                         raise QAPIParseError(self, 'Missing terminating "\'"')
                     if esc:
-                        # Note: we don't recognize escape sequences
-                        # for control characters
-                        if ch == 'u':
-                            value = 0
-                            for _ in range(0, 4):
-                                ch = self.src[self.cursor]
-                                self.cursor += 1
-                                if ch not in '0123456789abcdefABCDEF':
-                                    raise QAPIParseError(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 not value or value > 0x7f:
-                                raise QAPIParseError(self,
-                                                     'For now, \\u escape '
-                                                     'only supports non-zero '
-                                                     'values up to \\u007f')
-                            ch = chr(value)
-                        elif ch not in '\\/\'"':
+                        # Note: we recognize only \\ because we have
+                        # no use for funny characters in strings
+                        if ch != '\\':
                             raise QAPIParseError(self,
                                                  "Unknown escape \\%s" % ch)
                         esc = False
diff --git a/tests/Makefile.include b/tests/Makefile.include
index 393cfd7..8585e7e 100644
--- a/tests/Makefile.include
+++ b/tests/Makefile.include
@@ -374,9 +374,6 @@ qapi-schema += enum-int-member.json
 qapi-schema += enum-member-case.json
 qapi-schema += enum-missing-data.json
 qapi-schema += enum-wrong-data.json
-qapi-schema += escape-outside-string.json
-qapi-schema += escape-too-big.json
-qapi-schema += escape-too-short.json
 qapi-schema += event-boxed-empty.json
 qapi-schema += event-case.json
 qapi-schema += event-member-invalid-dict.json
diff --git a/tests/qapi-schema/escape-outside-string.err b/tests/qapi-schema/escape-outside-string.err
deleted file mode 100644
index b9b8837..0000000
--- a/tests/qapi-schema/escape-outside-string.err
+++ /dev/null
@@ -1 +0,0 @@
-tests/qapi-schema/escape-outside-string.json:3:27: Stray "\"
diff --git a/tests/qapi-schema/escape-outside-string.exit b/tests/qapi-schema/escape-outside-string.exit
deleted file mode 100644
index d00491f..0000000
--- a/tests/qapi-schema/escape-outside-string.exit
+++ /dev/null
@@ -1 +0,0 @@
-1
diff --git a/tests/qapi-schema/escape-outside-string.json b/tests/qapi-schema/escape-outside-string.json
deleted file mode 100644
index 482f795..0000000
--- a/tests/qapi-schema/escape-outside-string.json
+++ /dev/null
@@ -1,3 +0,0 @@
-# escape sequences are permitted only inside strings
-# { 'command': 'foo', 'data': {} }
-{ 'command': 'foo', 'data'\u003a{} }
diff --git a/tests/qapi-schema/escape-outside-string.out b/tests/qapi-schema/escape-outside-string.out
deleted file mode 100644
index e69de29..0000000
--- a/tests/qapi-schema/escape-outside-string.out
+++ /dev/null
diff --git a/tests/qapi-schema/escape-too-big.err b/tests/qapi-schema/escape-too-big.err
deleted file mode 100644
index d9aeb5d..0000000
--- a/tests/qapi-schema/escape-too-big.err
+++ /dev/null
@@ -1 +0,0 @@
-tests/qapi-schema/escape-too-big.json:3:14: For now, \u escape only supports non-zero values up to \u007f
diff --git a/tests/qapi-schema/escape-too-big.exit b/tests/qapi-schema/escape-too-big.exit
deleted file mode 100644
index d00491f..0000000
--- a/tests/qapi-schema/escape-too-big.exit
+++ /dev/null
@@ -1 +0,0 @@
-1
diff --git a/tests/qapi-schema/escape-too-big.json b/tests/qapi-schema/escape-too-big.json
deleted file mode 100644
index 62bcecd..0000000
--- a/tests/qapi-schema/escape-too-big.json
+++ /dev/null
@@ -1,3 +0,0 @@
-# we don't support full Unicode strings, yet
-# { 'command': 'é' }
-{ 'command': '\u00e9' }
diff --git a/tests/qapi-schema/escape-too-big.out b/tests/qapi-schema/escape-too-big.out
deleted file mode 100644
index e69de29..0000000
--- a/tests/qapi-schema/escape-too-big.out
+++ /dev/null
diff --git a/tests/qapi-schema/escape-too-short.err b/tests/qapi-schema/escape-too-short.err
deleted file mode 100644
index 934de59..0000000
--- a/tests/qapi-schema/escape-too-short.err
+++ /dev/null
@@ -1 +0,0 @@
-tests/qapi-schema/escape-too-short.json:3:14: \u escape needs 4 hex digits
diff --git a/tests/qapi-schema/escape-too-short.exit b/tests/qapi-schema/escape-too-short.exit
deleted file mode 100644
index d00491f..0000000
--- a/tests/qapi-schema/escape-too-short.exit
+++ /dev/null
@@ -1 +0,0 @@
-1
diff --git a/tests/qapi-schema/escape-too-short.json b/tests/qapi-schema/escape-too-short.json
deleted file mode 100644
index 6cb1dec..0000000
--- a/tests/qapi-schema/escape-too-short.json
+++ /dev/null
@@ -1,3 +0,0 @@
-# the \u escape requires 4 hex digits
-# { 'command': 'a' }
-{ 'command': '\u61' }
diff --git a/tests/qapi-schema/escape-too-short.out b/tests/qapi-schema/escape-too-short.out
deleted file mode 100644
index e69de29..0000000
--- a/tests/qapi-schema/escape-too-short.out
+++ /dev/null
diff --git a/tests/qapi-schema/ident-with-escape.err b/tests/qapi-schema/ident-with-escape.err
index e69de29..5517dcb 100644
--- a/tests/qapi-schema/ident-with-escape.err
+++ b/tests/qapi-schema/ident-with-escape.err
@@ -0,0 +1 @@
+tests/qapi-schema/ident-with-escape.json:3:3: Unknown escape \u
diff --git a/tests/qapi-schema/ident-with-escape.exit b/tests/qapi-schema/ident-with-escape.exit
index 573541a..d00491f 100644
--- a/tests/qapi-schema/ident-with-escape.exit
+++ b/tests/qapi-schema/ident-with-escape.exit
@@ -1 +1 @@
-0
+1
diff --git a/tests/qapi-schema/ident-with-escape.json b/tests/qapi-schema/ident-with-escape.json
index 5661750..76b4503 100644
--- a/tests/qapi-schema/ident-with-escape.json
+++ b/tests/qapi-schema/ident-with-escape.json
@@ -1,4 +1,4 @@
-# we allow escape sequences in strings, if they map back to ASCII
+# we don't recognize any \ escapes other than \\ (tested elsewhere)
 # { 'command': 'fooA', 'data': { 'bar1': 'str' } }
 { 'c\u006fmmand': '\u0066\u006f\u006FA',
   'd\u0061ta': { '\u0062\u0061\u00721': '\u0073\u0074\u0072' } }
diff --git a/tests/qapi-schema/ident-with-escape.out b/tests/qapi-schema/ident-with-escape.out
index 39754eb..e69de29 100644
--- a/tests/qapi-schema/ident-with-escape.out
+++ b/tests/qapi-schema/ident-with-escape.out
@@ -1,16 +0,0 @@
-module None
-object q_empty
-enum QType
-    prefix QTYPE
-    member none
-    member qnull
-    member qnum
-    member qstring
-    member qdict
-    member qlist
-    member qbool
-module ident-with-escape.json
-object q_obj_fooA-arg
-    member bar1: str optional=False
-command fooA q_obj_fooA-arg -> None
-   gen=True success_response=True boxed=False oob=False preconfig=False
diff --git a/tests/qapi-schema/unknown-escape.json b/tests/qapi-schema/unknown-escape.json
index 8e6891e..8372e80 100644
--- a/tests/qapi-schema/unknown-escape.json
+++ b/tests/qapi-schema/unknown-escape.json
@@ -1,3 +1,3 @@
-# we only recognize JSON escape sequences, plus our \' extension (no \x)
+# we only recognize \\
 # { 'command': 'foo', 'data': {} }
 { 'command': 'foo', 'dat\x61':{} }