Refactor spec parser and consolidate ASN.1 constants

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -53,7 +53,7 @@ body:
       description: Provide a minimal C code example that demonstrates the issue
       render: c
       placeholder: |
-        #include "J2735_macros.h"
+        #include "J2735_api.h"
 
         int main(void) {
             uint8_t buf[] = { 0x15, 0xBD, ... };

.github/instructions/j2735_design.instructions.md

@@ -18,7 +18,7 @@ The library splits the concept of a "Message" into two layers to map high-level
   - Use "Container Structs" (byte arrays) only for pointer sizing, not for member access.
   - **Anti-Pattern**: Do not define standard C structs with members for data access.
 
-### 2. The Access Layer (`J2735_macros.h`)
+### 2. The Access Layer (`J2735_internal_common.h`)
 
 - **Concept**: Acts as the optical lens to read the data.
 - **Usage**:

.github/workflows/ci.yml

@@ -56,6 +56,10 @@ on:
     branches:
       - main
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 permissions:
   contents: write
   pull-requests: write

.github/workflows/pr-compliance.yml

@@ -32,6 +32,10 @@ on:
       - reopened
       - synchronize
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 # Security: Minimal permissions - read PR, write status checks
 permissions:
   pull-requests: read

.github/workflows/python.yml

@@ -55,6 +55,10 @@ on:
       - 'tools/**'
       - '.github/workflows/python.yml'
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 permissions:
   contents: write
   pull-requests: write

tools/j2735_asn1_constants.py

@@ -0,0 +1,38 @@
+# Copyright 2026 Yogev Neumann
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: 2026 Yogev Neumann
+"""
+ASN.1 language constants shared across J2735 parsing modules.
+
+Central repository for ASN.1 syntax tokens and patterns
+used throughout the J2735 toolchain.
+"""
+
+from re import DOTALL, MULTILINE, Pattern
+from re import compile as re_compile
+from typing import Final
+
+# ASN.1 syntax tokens
+ASN1_COMMENT_PREFIX: Final[str] = "--"
+ASN1_EXTENSION_MARKER: Final[str] = "..."
+ASN1_FIELD_SEPARATOR: Final[str] = ","
+ASN1_OPTIONAL_KEYWORD: Final[str] = "OPTIONAL"
+ASN1_SEQUENCE_KEYWORD: Final[str] = "SEQUENCE"
+
+# ASN.1 type definition patterns
+# Note: [\w-]+ allows hyphens in type names (e.g., Offset-B10, OffsetLL-B12)
+ASN1_TYPE_DEF_PATTERN: Final[Pattern[str]] = re_compile(r"^([\w-]+)\s*::=\s*(.+)$", MULTILINE)
+ASN1_TYPE_DEF_DOTALL_PATTERN: Final[Pattern[str]] = re_compile(r"([\w-]+)\s*::=\s*(.+)", DOTALL)

tools/j2735_c_generator_bitwidth_constants.py

@@ -30,7 +30,7 @@
 """
 
 from .j2735_c_generator_jinja import create_jinja_env, get_template
-from .j2735_spec_parser import ASN1TypeDefinition, J2735Specification
+from .j2735_spec_parser import J2735Specification
 
 _BITWIDTH_TEMPLATE_NAME = "bitwidth_constants.j2"
 
@@ -58,15 +58,7 @@ def generate_bitwidth_constants(spec: J2735Specification) -> str:
         >>> "7U" in code
         True
     """
-    # Collect types with fixed bit-widths
-    fixed_types: list[ASN1TypeDefinition] = []
-    variable_count = 0
-
-    for _, typedef in sorted(spec.type_registry.items()):
-        if typedef.uper_bit_width is not None:
-            fixed_types.append(typedef)
-        else:
-            variable_count += 1
+    fixed_types, variable_count = spec.collect_fixed_width_types()
 
     env = create_jinja_env()
     template = get_template(env, _BITWIDTH_TEMPLATE_NAME)

tools/j2735_c_generator_size_constants.py

@@ -31,7 +31,7 @@
 """
 
 from .j2735_c_generator_jinja import create_jinja_env, get_template
-from .j2735_spec_parser import ASN1TypeDefinition, J2735Specification
+from .j2735_spec_parser import J2735Specification
 
 _TEMPLATE_NAME = "size_constants.j2"
 
@@ -57,12 +57,7 @@ def generate_size_constants(spec: J2735Specification) -> str:
         >>> "37U" in code  # 290 bits -> 37 bytes
         True
     """
-    # Collect types with fixed bit-widths (same as bitwidth generator)
-    fixed_types: list[ASN1TypeDefinition] = []
-
-    for _, typedef in sorted(spec.type_registry.items()):
-        if typedef.uper_bit_width is not None:
-            fixed_types.append(typedef)
+    fixed_types, _ = spec.collect_fixed_width_types()
 
     env = create_jinja_env()
     template = get_template(env, _TEMPLATE_NAME)

tools/j2735_spec_constraints.py

@@ -38,17 +38,19 @@
 from re import compile as re_compile
 from typing import Annotated, ClassVar, Final, Self
 
+from .j2735_asn1_constants import (
+    ASN1_COMMENT_PREFIX,
+    ASN1_EXTENSION_MARKER,
+    ASN1_FIELD_SEPARATOR,
+    ASN1_OPTIONAL_KEYWORD,
+    ASN1_SEQUENCE_KEYWORD,
+)
+
 # These type aliases document constraints that are validated at runtime
 # via __post_init__. They help communicate intent to readers and tools.
 _PositiveInt = Annotated[int, "Value must be >= 1"]
 _NonNegativeInt = Annotated[int, "Value must be >= 0"]
 
-# ASN.1 parsing constants
-_ASN1_COMMENT_PREFIX: Final[str] = "--"
-_ASN1_EXTENSION_MARKER: Final[str] = "..."
-_ASN1_FIELD_SEPARATOR: Final[str] = ","
-_ASN1_OPTIONAL_KEYWORD: Final[str] = "OPTIONAL"
-_ASN1_SEQUENCE_KEYWORD: Final[str] = "SEQUENCE"
 _BITS_PER_BYTE: Final[int] = 8  # 8 bits per byte/octet in OCTET STRING
 
 # J2735-specific constants
@@ -560,7 +562,7 @@ def from_asn1(cls, raw_def: str) -> Self | None:
             return None
 
         body = match.group(1)
-        is_extensible = _ASN1_EXTENSION_MARKER in body
+        is_extensible = ASN1_EXTENSION_MARKER in body
 
         # Parse individual alternatives
         alternatives: dict[str, str] = {}
@@ -569,9 +571,7 @@ def from_asn1(cls, raw_def: str) -> Self | None:
             type_ref = alt_match.group(2).strip()
             # Skip J2735 regional extension fields (SEQUENCE OF RegionalExtension)
             # These are variable-length and would break fixed bit-width calculation
-            if name != _J2735_REGIONAL_FIELD_NAME or not type_ref.startswith(
-                _ASN1_SEQUENCE_KEYWORD
-            ):
+            if name != _J2735_REGIONAL_FIELD_NAME or not type_ref.startswith(ASN1_SEQUENCE_KEYWORD):
                 alternatives[name] = type_ref
 
         if not alternatives:
@@ -836,7 +836,7 @@ def from_asn1(cls, raw_def: str) -> Self | None:
         # Assign values in document order
         values = cls._assign_values(all_items)
 
-        return cls(values=values, is_extensible=_ASN1_EXTENSION_MARKER in body)
+        return cls(values=values, is_extensible=ASN1_EXTENSION_MARKER in body)
 
 
 @dataclass(frozen=True, kw_only=True, slots=True)
@@ -1293,36 +1293,36 @@ def from_asn1(cls, raw_def: str) -> tuple[Self, ...]:
                 continue
 
             # Check if this is a standalone comment line (starts with --)
-            if line.startswith(_ASN1_COMMENT_PREFIX):
+            if line.startswith(ASN1_COMMENT_PREFIX):
                 pending_section_comment = line[
-                    len(_ASN1_COMMENT_PREFIX) :  # noqa: E203  # Black VS flake8
+                    len(ASN1_COMMENT_PREFIX) :  # noqa: E203  # Black VS flake8
                 ].strip()
                 continue
 
             # Extract inline comment from end of line
             line_inline_comment: str = ""
-            comment_pos = line.find(_ASN1_COMMENT_PREFIX)
+            comment_pos = line.find(ASN1_COMMENT_PREFIX)
             if comment_pos != -1:
                 line_inline_comment = line[
-                    comment_pos + len(_ASN1_COMMENT_PREFIX) :  # noqa: E203  # Black VS flake8
+                    comment_pos + len(ASN1_COMMENT_PREFIX) :  # noqa: E203  # Black VS flake8
                 ].strip()
                 line = line[:comment_pos].strip()
 
             # Split line by field separator to get individual fields
-            parts = [p.strip() for p in line.split(_ASN1_FIELD_SEPARATOR) if p.strip()]
+            parts = [p.strip() for p in line.split(ASN1_FIELD_SEPARATOR) if p.strip()]
 
             # Process each field part
             for index, part in enumerate(parts):
                 # Skip extension markers
-                if part == _ASN1_EXTENSION_MARKER:
+                if part == ASN1_EXTENSION_MARKER:
                     continue
 
                 # Parse "fieldName TypeName OPTIONAL" or "fieldName TypeName"
                 tokens = part.split()
                 if len(tokens) < 2:
                     continue
 
-                is_optional = _ASN1_OPTIONAL_KEYWORD in tokens[2:] if len(tokens) > 2 else False
+                is_optional = ASN1_OPTIONAL_KEYWORD in tokens[2:] if len(tokens) > 2 else False
 
                 # Inline comment only applies to the LAST field on the line
                 inline_comment = line_inline_comment if index == len(parts) - 1 else ""
@@ -1685,12 +1685,12 @@ def from_asn1(cls, raw_def: str) -> Self | None:
             True
         """
         # Must start with SEQUENCE keyword (not CHOICE, etc.)
-        if not raw_def.strip().startswith(_ASN1_SEQUENCE_KEYWORD):
+        if not raw_def.strip().startswith(ASN1_SEQUENCE_KEYWORD):
             return None
         fields = SequenceField.from_asn1(raw_def)
         if not fields:
             return None
-        is_extensible = _ASN1_EXTENSION_MARKER in raw_def
+        is_extensible = ASN1_EXTENSION_MARKER in raw_def
         return cls(fields=fields, is_extensible=is_extensible)