[PATCH net-next v2 10/12] tools: ynl-gen: array-nest: support binary array with exact-len

[Jakub Kicinski <kuba@kernel.org>]

IPv6 addresses are expressed as binary arrays since we don't have u128.
Since they are not variable length, however, they are relatively
easy to represent as an array of known size.

Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 tools/net/ynl/pyynl/ynl_gen_c.py | 24 ++++++++++++++++++++----
 1 file changed, 20 insertions(+), 4 deletions(-)

diff --git a/tools/net/ynl/pyynl/ynl_gen_c.py b/tools/net/ynl/pyynl/ynl_gen_c.py
index a4e65da19696..2d185c7ea16c 100755
--- a/tools/net/ynl/pyynl/ynl_gen_c.py
+++ b/tools/net/ynl/pyynl/ynl_gen_c.py
@@ -183,10 +183,10 @@ from lib import SpecFamily, SpecAttrSet, SpecAttr, SpecOperation, SpecEnumSet, S
         raise Exception(f"Struct member not implemented for class type {self.type}")
 
     def struct_member(self, ri):
-        if self.is_multi_val():
-            ri.cw.p(f"unsigned int n_{self.c_name};")
         member = self._complex_member_type(ri)
         if member:
+            if self.is_multi_val():
+                ri.cw.p(f"unsigned int n_{self.c_name};")
             ptr = '*' if self.is_multi_val() else ''
             if self.is_recursive_for_op(ri):
                 ptr = '*'
@@ -728,12 +728,22 @@ from lib import SpecFamily, SpecAttrSet, SpecAttr, SpecOperation, SpecEnumSet, S
         elif self.attr['sub-type'] in scalars:
             scalar_pfx = '__' if ri.ku_space == 'user' else ''
             return scalar_pfx + self.attr['sub-type']
+        elif self.attr['sub-type'] == 'binary' and 'exact-len' in self.checks:
+            return None  # use arg_member()
         else:
             raise Exception(f"Sub-type {self.attr['sub-type']} not supported yet")
 
+    def arg_member(self, ri):
+        if self.sub_type == 'binary' and 'exact-len' in self.checks:
+            return [f'unsigned char (*{self.c_name})[{self.checks["exact-len"]}]',
+                    f'unsigned int n_{self.c_name}']
+        return super().arg_member(ri)
+
     def _attr_typol(self):
         if self.attr['sub-type'] in scalars:
             return f'.type = YNL_PT_U{c_upper(self.sub_type[1:])}, '
+        elif self.attr['sub-type'] == 'binary' and 'exact-len' in self.checks:
+            return f'.type = YNL_PT_BINARY, .len = {self.checks["exact-len"]}, '
         else:
             return f'.type = YNL_PT_NEST, .nest = &{self.nested_render_name}_nest, '
 
@@ -754,6 +764,9 @@ from lib import SpecFamily, SpecAttrSet, SpecAttr, SpecOperation, SpecEnumSet, S
             ri.cw.block_start(line=f'for (i = 0; i < {var}->n_{self.c_name}; i++)')
             ri.cw.p(f"ynl_attr_put_{put_type}(nlh, i, {var}->{self.c_name}[i]);")
             ri.cw.block_end()
+        elif self.sub_type == 'binary' and 'exact-len' in self.checks:
+            ri.cw.p(f'for (i = 0; i < {var}->n_{self.c_name}; i++)')
+            ri.cw.p(f"ynl_attr_put(nlh, i, {var}->{self.c_name}[i], {self.checks['exact-len']});")
         else:
             raise Exception(f"Put for ArrayNest sub-type {self.attr['sub-type']} not supported, yet")
         ri.cw.p('ynl_attr_nest_end(nlh, array);')
@@ -964,7 +977,7 @@ from lib import SpecFamily, SpecAttrSet, SpecAttr, SpecOperation, SpecEnumSet, S
         elif elem['type'] == 'nest':
             t = TypeNest(self.family, self, elem, value)
         elif elem['type'] == 'indexed-array' and 'sub-type' in elem:
-            if elem["sub-type"] in ['nest', 'u32']:
+            if elem["sub-type"] in ['binary', 'nest', 'u32']:
                 t = TypeArrayNest(self.family, self, elem, value)
             else:
                 raise Exception(f'new_attr: unsupported sub-type {elem["sub-type"]}')
@@ -1786,7 +1799,7 @@ _C_KW = {
     needs_parg = False
     for arg, aspec in struct.member_list():
         if aspec['type'] == 'indexed-array' and 'sub-type' in aspec:
-            if aspec["sub-type"] == 'nest':
+            if aspec["sub-type"] in {'binary', 'nest'}:
                 local_vars.append(f'const struct nlattr *attr_{aspec.c_name};')
                 array_nests.add(arg)
             elif aspec['sub-type'] in scalars:
@@ -1859,6 +1872,9 @@ _C_KW = {
             ri.cw.p('return YNL_PARSE_CB_ERROR;')
         elif aspec.sub_type in scalars:
             ri.cw.p(f"dst->{aspec.c_name}[i] = ynl_attr_get_{aspec.sub_type}(attr);")
+        elif aspec.sub_type == 'binary' and 'exact-len' in aspec.checks:
+            # Length is validated by typol
+            ri.cw.p(f'memcpy(dst->{aspec.c_name}[i], ynl_attr_data(attr), {aspec.checks["exact-len"]});')
         else:
             raise Exception(f"Nest parsing type not supported in {aspec['name']}")
         ri.cw.p('i++;')
-- 
2.49.0