api: enforce vla is last and fixed string type
Enforce that variable length fields are the last element of API messages.
Add a 'fixed' version of string type, since dealing with
multiple variable length strings turned out too painful
for the C language bindings.
The string type is now:
{
string name[64]; // NUL terminated C-string. Essentially decays to u8 name[64]
string name[]; // Variable length string with embedded len field (vl_api_string_t)
};
The latter notation could be made available to other types as well.
e.g.
{
vl_api_address_t addresses[];
}
instead of
{
u32 n_addr;
vl_api_address_t addresses[n_addr];
};
Type: fix
Change-Id: I18fa17ef47227633752ab50453e8d20a652a9f9b
Signed-off-by: Ole Troan <ot@cisco.com>
diff --git a/src/tools/vppapigen/vppapigen.py b/src/tools/vppapigen/vppapigen.py
index c01fa40..d0391cd 100755
--- a/src/tools/vppapigen/vppapigen.py
+++ b/src/tools/vppapigen/vppapigen.py
@@ -152,6 +152,25 @@
self.manual_endian = True
global_type_add(name, self)
+ self.vla = False
+
+ for i, b in enumerate(block):
+ if isinstance(b, Array):
+ if b.length == 0:
+ self.vla = True
+ if i + 1 < len(block):
+ raise ValueError(
+ 'VLA field "{}" must be the last '
+ 'field in message "{}"'
+ .format(b.fieldname, name))
+ elif b.fieldtype == 'string':
+ self.vla = True
+ if i + 1 < len(block):
+ raise ValueError(
+ 'VLA field "{}" must be the last '
+ 'field in message "{}"'
+ .format(b.fieldname, name))
+
def __repr__(self):
return self.name + str(self.flags) + str(self.block)
@@ -159,12 +178,13 @@
class Using():
def __init__(self, name, alias):
self.name = name
+ self.vla = False
if isinstance(alias, Array):
- a = { 'type': alias.fieldtype, # noqa: E201
- 'length': alias.length } # noqa: E202
+ a = {'type': alias.fieldtype,
+ 'length': alias.length}
else:
- a = { 'type': alias.fieldtype } # noqa: E201,E202
+ a = {'type': alias.fieldtype}
self.alias = a
self.crc = str(alias).encode()
global_type_add(name, self)
@@ -208,12 +228,29 @@
elif f == 'autoreply':
self.autoreply = True
- for b in block:
+ for i, b in enumerate(block):
if isinstance(b, Option):
if b[1] == 'singular' and b[2] == 'true':
self.singular = True
block.remove(b)
+ if isinstance(b, Array) and b.vla and i + 1 < len(block):
+ raise ValueError(
+ 'VLA field "{}" must be the last field in message "{}"'
+ .format(b.fieldname, name))
+ elif b.fieldtype.startswith('vl_api_'):
+ if (global_types[b.fieldtype].vla and i + 1 < len(block)):
+ raise ValueError(
+ 'VLA field "{}" must be the last '
+ 'field in message "{}"'
+ .format(b.fieldname, name))
+ elif b.fieldtype == 'string' and b.length == 0:
+ if i + 1 < len(block):
+ raise ValueError(
+ 'VLA field "{}" must be the last '
+ 'field in message "{}"'
+ .format(b.fieldname, name))
+
def __repr__(self):
return self.name + str(self.flags) + str(self.block)
@@ -222,6 +259,7 @@
def __init__(self, name, block, enumtype='u32'):
self.name = name
self.enumtype = enumtype
+ self.vla = False
count = 0
for i, b in enumerate(block):
@@ -272,16 +310,19 @@
class Array():
- def __init__(self, fieldtype, name, length):
+ def __init__(self, fieldtype, name, length, modern_vla=False):
self.type = 'Array'
self.fieldtype = fieldtype
self.fieldname = name
+ self.modern_vla = modern_vla
if type(length) is str:
self.lengthfield = length
self.length = 0
+ self.vla = True
else:
self.length = length
self.lengthfield = None
+ self.vla = False
def __repr__(self):
return str([self.fieldtype, self.fieldname, self.length,
@@ -292,6 +333,11 @@
def __init__(self, fieldtype, name, limit=None):
self.type = 'Field'
self.fieldtype = fieldtype
+
+ if self.fieldtype == 'string':
+ raise ValueError("The string type {!r} is an "
+ "array type ".format(name))
+
if name in keyword.kwlist:
raise ValueError("Fieldname {!r} is a python keyword and is not "
"accessible via the python API. ".format(name))
@@ -521,13 +567,18 @@
if len(p) == 2:
p[0] = p[1]
else:
- p[0] = { **p[1], **p[2] }
+ p[0] = {**p[1], **p[2]}
def p_field_option(self, p):
- '''field_option : ID '=' assignee ','
+ '''field_option : ID
+ | ID '=' assignee ','
| ID '=' assignee
+
'''
- p[0] = { p[1]: p[3] }
+ if len(p) == 2:
+ p[0] = {p[1]: None}
+ else:
+ p[0] = {p[1]: p[3]}
def p_declaration(self, p):
'''declaration : type_specifier ID ';'
@@ -540,9 +591,14 @@
self._parse_error('ERROR')
self.fields.append(p[2])
+ def p_declaration_array_vla(self, p):
+ '''declaration : type_specifier ID '[' ']' ';' '''
+ p[0] = Array(p[1], p[2], 0, modern_vla=True)
+
def p_declaration_array(self, p):
'''declaration : type_specifier ID '[' NUM ']' ';'
| type_specifier ID '[' ID ']' ';' '''
+
if len(p) != 7:
return self._parse_error(
'array: %s' % p.value,
@@ -780,7 +836,7 @@
try:
crc = crc_block_combine(t.block, crc)
return foldup_blocks(t.block, crc)
- except:
+ except AttributeError:
pass
return crc
diff --git a/src/tools/vppapigen/vppapigen_c.py b/src/tools/vppapigen/vppapigen_c.py
index 19efc99..c1bc11d 100644
--- a/src/tools/vppapigen/vppapigen_c.py
+++ b/src/tools/vppapigen/vppapigen_c.py
@@ -153,8 +153,15 @@
if b.lengthfield:
output += " %s %s[0];\n" % (api2c(b.fieldtype), b.fieldname)
else:
- output += " %s %s[%s];\n" % (api2c(b.fieldtype), b.fieldname,
- b.length)
+ # Fixed length strings decay to nul terminated u8
+ if b.fieldtype == 'string':
+ if b.modern_vla:
+ output += ' {} {};\n'.format(api2c(b.fieldtype), b.fieldname)
+ else:
+ output += ' u8 {}[{}];\n'.format(b.fieldname, b.length)
+ else:
+ output += " %s %s[%s];\n" % (api2c(b.fieldtype), b.fieldname,
+ b.length)
else:
raise ValueError("Error in processing array type %s" % b)