Propagate XML file licenses into generated C code.

registers.py

@@ -14,7 +14,7 @@
 
 class Registers( object ):
     def __init__( self, name, label, prefix, description, skip_index,
-            skip_access, skip_reset, depth ):
+            skip_access, skip_reset, depth, licenses ):
         self.name = name
         self.label = label
         self.prefix = prefix or ""
@@ -23,6 +23,7 @@ def __init__( self, name, label, prefix, description, skip_index,
         self.skip_access = skip_access
         self.skip_reset = skip_reset
         self.depth = depth
+        self.licenses = licenses
         self.registers = []
 
     def add_register( self, register ):
@@ -279,7 +280,13 @@ def parse_bits( field ):
     else:
         assert False, text
 
+def parse_spdx( path ):
+    with open( path ) as f:
+        data = f.read(65536)
+        return set(re.findall(r"SPDX-License-Identifier:\s*(.+)$", data, re.MULTILINE))
+
 def parse_xml( path ):
+    licenses = parse_spdx(path)
     e = xml.etree.ElementTree.parse( path ).getroot()
     if e.text:
         description = e.text.strip()
@@ -290,7 +297,8 @@ def parse_xml( path ):
             int( e.get( 'skip_index', 0 ) ),
             int( e.get( 'skip_access', 0 ) ),
             int( e.get( 'skip_reset', 0 ) ),
-            int( e.get( 'depth', 1 )))
+            int( e.get( 'depth', 1 )),
+            licenses)
     for r in e.findall( 'register' ):
         name = r.get( 'name' )
         short = r.get( 'short' )
@@ -423,6 +431,10 @@ def c_max(args):
         return c_max(args)
     raise Exception("Unsupported sympy object %r of type %r" % (expression, type(expression)))
 
+def write_c_licenses( fd, licenses ):
+    for license in licenses:
+        fd.write(f"/* SPDX-License-Identifier: {license} */\n")
+
 def write_cheader( fd, registers ):
     definitions = []
     for r in registers.registers:
@@ -815,11 +827,17 @@ def main():
     parsed = parser.parse_args()
 
     if (parsed.xml_paths):
+        registers_list = [parse_xml( xml_path ) for xml_path in parsed.xml_paths]
+        license_lists = [registers.licenses for registers in registers_list]
+        # Assert every license list is the same
+        assert all(license_lists[0] == license_list for license_list in license_lists), \
+                "All XML files must have the same SPDX-License-Identifier"
         fd_h = open( parsed.path + ".h", "a" )
+        write_c_licenses( fd_h, license_lists[0] )
         fd_h.write("#ifndef DEBUG_DEFINES_H\n#define DEBUG_DEFINES_H\n")
         fd_c = open( parsed.path + ".c", "a" )
+        write_c_licenses( fd_c, license_lists[0] )
         fd_c.write(f'#include "{parsed.path}.h"\n#include <stddef.h>\n#include <assert.h>\n')
-        registers_list = [parse_xml( xml_path ) for xml_path in parsed.xml_paths]
         for registers in registers_list:
             write_cheader( fd_h, registers )
         print_cgetters(registers_list, fd_h, fd_c)
@@ -830,7 +848,9 @@ def main():
     if parsed.definitions:
         write_definitions( open( parsed.definitions, "w" ), registers )
     if parsed.cheader:
-        write_cheader( open( parsed.cheader, "w" ), registers )
+        with open( parsed.cheader, "w" ) as fd:
+            write_c_licenses( fd, registers.licenses )
+            write_cheader( fd, registers )
     if parsed.chisel:
         write_chisel( open( parsed.chisel, "w" ), registers )
     if not registers.skip_index: