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>

1 files changed, 23 insertions, 4 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)