license.bbclass: Introduce AVAILABLE_LICENSES that lists all licenses

Previously, there was SRC_DISTRIBUTE_LICENSES, an undocumented
variable that contained a static list of licenses. It was used by
expand_wildcard_licenses() to expand any wildcards used in, e.g.,
INCOMPATIBLE_LICENSE. However, since this static list of licenses has
not been kept up-to-date, many licenses were missing, with the result
that if one tried to use any of those licenses with a wildcard, no
licenses would be found, effectively ignoring that they should be
marked as incompatible.

This introduces a new (documented) variable, AVAILABLE_LICENSES, that
is automatically updated to contain all licenses found in any
directories specified by ${COMMON_LICENSE_DIR} and ${LICENSE_PATH},
and uses it instead of SRC_DISTRIBUTE_LICENSES when expanding
wildcards.

Signed-off-by: Peter Kjellerstedt <peter.kjellerstedt@axis.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

3 files changed, 27 insertions, 7 deletions

diff --git a/meta/classes/license.bbclass b/meta/classes/license.bbclass
index 648a4d7892..c388740003 100644
--- a/meta/classes/license.bbclass
+++ b/meta/classes/license.bbclass
@@ -252,7 +252,7 @@ def canonical_license(d, license):
     """
     Return the canonical (SPDX) form of the license if available (so GPLv3
     becomes GPL-3.0), for the license named 'X+', return canonical form of
-    'X' if availabel and the tailing '+' (so GPLv3+ becomes GPL-3.0+), 
+    'X' if available and the tailing '+' (so GPLv3+ becomes GPL-3.0+),
     or the passed license if there is no canonical form.
     """
     lic = d.getVarFlag('SPDXLICENSEMAP', license) or ""
@@ -262,10 +262,29 @@ def canonical_license(d, license):
             lic += '+'
     return lic or license
 
+def available_licenses(d):
+    """
+    Return the available licenses by searching the directories specified by
+    COMMON_LICENSE_DIR and LICENSE_PATH.
+    """
+    lic_dirs = ((d.getVar('COMMON_LICENSE_DIR') or '') + ' ' +
+                (d.getVar('LICENSE_PATH') or '')).split()
+
+    licenses = []
+    for lic_dir in lic_dirs:
+        licenses += os.listdir(lic_dir)
+
+    licenses = sorted(licenses)
+    return licenses
+
+# Only determine the list of all available licenses once. This assumes that any
+# additions to LICENSE_PATH have been done before this file is parsed.
+AVAILABLE_LICENSES := "${@' '.join(available_licenses(d))}"
+
 def expand_wildcard_licenses(d, wildcard_licenses):
     """
-    Return actual spdx format license names if wildcard used. We expand
-    wildcards from SPDXLICENSEMAP flags and SRC_DISTRIBUTE_LICENSES values.
+    Return actual spdx format license names if wildcards are used. We expand
+    wildcards from SPDXLICENSEMAP flags and AVAILABLE_LICENSES.
     """
     import fnmatch
     licenses = wildcard_licenses[:]
@@ -274,7 +293,7 @@ def expand_wildcard_licenses(d, wildcard_licenses):
         spdxflags = fnmatch.filter(spdxmapkeys, wld_lic)
         licenses += [d.getVarFlag('SPDXLICENSEMAP', flag) for flag in spdxflags]
 
-    spdx_lics = (d.getVar('SRC_DISTRIBUTE_LICENSES', False) or '').split()
+    spdx_lics = d.getVar('AVAILABLE_LICENSES').split()
     for wld_lic in wildcard_licenses:
         licenses += fnmatch.filter(spdx_lics, wld_lic)
 
diff --git a/meta/conf/documentation.conf b/meta/conf/documentation.conf
index fca36f3cf6..0b21d1f63e 100644
--- a/meta/conf/documentation.conf
+++ b/meta/conf/documentation.conf
@@ -69,6 +69,7 @@ ASSUME_SHLIBS[doc] = "List of shlib:package[_version] mappings. Useful for lib p
 AUTHOR[doc] = "Email address used to contact the original author(s) in order to send patches and forward bugs."
 AUTO_SYSLINUXMENU[doc] = "Enables creating an automatic menu for the syslinux bootloader."
 AUTOREV[doc] = "When SRCREV is set to the value of this variable, it specifies to use the latest source revision in the repository."
+AVAILABLE_LICENSES[doc] = "List of licenses found in the directories specified by COMMON_LICENSE_DIR and LICENSE_PATH."
 
 #B
 
diff --git a/meta/lib/oeqa/selftest/cases/incompatible_lic.py b/meta/lib/oeqa/selftest/cases/incompatible_lic.py
index 904b5b4094..ad878571b5 100644
--- a/meta/lib/oeqa/selftest/cases/incompatible_lic.py
+++ b/meta/lib/oeqa/selftest/cases/incompatible_lic.py
@@ -12,12 +12,12 @@ class IncompatibleLicenseTests(OESelftestTestCase):
         if error_msg not in result.output:
             raise AssertionError(result.output)
 
-    # Verify that a package with an SPDX license (from SRC_DISTRIBUTE_LICENSES)
+    # Verify that a package with an SPDX license (from AVAILABLE_LICENSES)
     # cannot be built when INCOMPATIBLE_LICENSE contains this SPDX license
     def test_incompatible_spdx_license(self):
         self.lic_test('incompatible-license', 'GPL-3.0', 'GPL-3.0')
 
-    # Verify that a package with an SPDX license (from SRC_DISTRIBUTE_LICENSES)
+    # Verify that a package with an SPDX license (from AVAILABLE_LICENSES)
     # cannot be built when INCOMPATIBLE_LICENSE contains an alias (in
     # SPDXLICENSEMAP) of this SPDX license
     def test_incompatible_alias_spdx_license(self):
@@ -35,7 +35,7 @@ class IncompatibleLicenseTests(OESelftestTestCase):
         self.lic_test('incompatible-license-alias', 'GPLv3', 'GPLv3')
 
     # Verify that a package with a non-SPDX license (neither in
-    # SRC_DISTRIBUTE_LICENSES nor in SPDXLICENSEMAP) cannot be built when
+    # AVAILABLE_LICENSES nor in SPDXLICENSEMAP) cannot be built when
     # INCOMPATIBLE_LICENSE contains this license
     def test_incompatible_nonspdx_license(self):
         self.lic_test('incompatible-nonspdx-license', 'FooLicense', 'FooLicense')