create-spdx: Get SPDX-License-Identifier from source

This patch will read the begining of source files and try to find
the SPDX-License-Identifier to populate the licenseInfoInFiles
field for each source file. This does not populate licenseConcluded
at this time, nor rolls it up to package level.

We read as binary file since some source code seem to have some
binary characters, the license is then converted to ascii strings.

Signed-off-by: Saul Wold <saul.wold@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

diff --git a/meta/classes/create-spdx.bbclass b/meta/classes/create-spdx.bbclass
index 8b4203fdb5d8114d2c324ee68dd2ed3ddf74a64a..64aada859374e3556fd0d1f968f92659d0f22b45 100644 (file)
--- a/meta/classes/create-spdx.bbclass
+++ b/meta/classes/create-spdx.bbclass
@@ -37,6 +37,23 @@ SPDX_SUPPLIER[doc] = "The SPDX PackageSupplier field for SPDX packages created f
 
 do_image_complete[depends] = "virtual/kernel:do_create_spdx"
 
+def extract_licenses(filename):
+    import re
+
+    lic_regex = re.compile(b'^\W*SPDX-License-Identifier:\s*([ \w\d.()+-]+?)(?:\s+\W*)?$', re.MULTILINE)
+
+    try:
+        with open(filename, 'rb') as f:
+            size = min(15000, os.stat(filename).st_size)
+            txt = f.read(size)
+            licenses = re.findall(lic_regex, txt)
+            if licenses:
+                ascii_licenses = [lic.decode('ascii') for lic in licenses]
+                return ascii_licenses
+    except Exception as e:
+        bb.warn(f"Exception reading {filename}: {e}")
+    return None
+
 def get_doc_namespace(d, doc):
     import uuid
     namespace_uuid = uuid.uuid5(uuid.NAMESPACE_DNS, d.getVar("SPDX_UUID_NAMESPACE"))
@@ -232,6 +249,11 @@ def add_package_files(d, doc, spdx_pkg, topdir, get_spdxid, get_types, *, archiv
                         checksumValue=bb.utils.sha256_file(filepath),
                     ))
 
+                if "SOURCE" in spdx_file.fileTypes:
+                    extracted_lics = extract_licenses(filepath)
+                    if extracted_lics:
+                        spdx_file.licenseInfoInFiles = extracted_lics
+
                 doc.files.append(spdx_file)
                 doc.add_relationship(spdx_pkg, "CONTAINS", spdx_file)
                 spdx_pkg.hasFiles.append(spdx_file.SPDXID)