[OE-core] [PATCH v2] base.bbclass: improve error message for missing host tools

[Alan Levy]

Host tools such as Subversion (svn) are not always installed or needed.
When they were required by a recipe but not installed the resulting error
message was not very user friendly. This patch generates a friendly error
message without forcing the user to install the tools if they aren't
needed.

Signed-off-by: Alan Levy <alan.levy at plextek.com>
---
meta/classes/base.bbclass | 16 ++++++++++++++--
meta/conf/bitbake.conf    |  4 ++++
meta/files/warnmissing.sh |  2 ++
3 files changed, 20 insertions(+), 2 deletions(-)
create mode 100755 meta/files/warnmissing.sh

diff --git a/meta/classes/base.bbclass b/meta/classes/base.bbclass
index 7892665..ecb6956 100644
--- a/meta/classes/base.bbclass
+++ b/meta/classes/base.bbclass
@@ -112,7 +112,9 @@ def get_lic_checksum_file_list(d):
             bb.fatal(d.getVar('PN') + ": LIC_FILES_CHKSUM contains an invalid URL: " + url)
     return " ".join(filelist)
-def setup_hosttools_dir(dest, toolsvar, d, fatal=True):
+def setup_hosttools_dir(dest, toolsvar, d, fatal=True, optional=False):
+    corebase = d.getVar('COREBASE')
+    toolwarningscript = os.path.join(corebase, "meta/files/warnmissing.sh")
     tools = d.getVar(toolsvar).split()
     origbbenv = d.getVar("BB_ORIGENV", False)
     path = origbbenv.getVar("PATH")
@@ -120,6 +122,10 @@ def setup_hosttools_dir(dest, toolsvar, d, fatal=True):
     notfound = []
     for tool in tools:
         desttool = os.path.join(dest, tool)
+        if optional and os.path.islink(desttool):
+            # For optional tools remove the symbolic link in case the host package has been
+            # installed or removed since we last ran
+            os.remove(desttool)
         if not os.path.exists(desttool):
             srctool = bb.utils.which(path, tool, executable=True)
             if "ccache" in srctool:
@@ -127,7 +133,12 @@ def setup_hosttools_dir(dest, toolsvar, d, fatal=True):
             if srctool:
                 os.symlink(srctool, desttool)
             else:
-                notfound.append(tool)
+                if optional:
+                    # Optional tools don't need to be present unless they are actually used by a recipe.
+                    # Set up a symlink to a script that generates a runtime error if the tool is used
+                    os.symlink(toolwarningscript, desttool)
+                else:
+                    notfound.append(tool)
     if notfound and fatal:
        bb.fatal("The following required tools (as specified by HOSTTOOLS) appear to be unavailable in PATH, please install them in order to proceed:\n  %s" % " ".join(notfound))
@@ -234,6 +245,7 @@ python base_eventhandler() {
         # Works with the line in layer.conf which changes PATH to point here
         setup_hosttools_dir(d.getVar('HOSTTOOLS_DIR'), 'HOSTTOOLS', d)
         setup_hosttools_dir(d.getVar('HOSTTOOLS_DIR'), 'HOSTTOOLS_NONFATAL', d, fatal=False)
+        setup_hosttools_dir(d.getVar('HOSTTOOLS_DIR'), 'HOSTTOOLS_OPTIONAL', d, fatal=False, optional=True)
     if isinstance(e, bb.event.BuildStarted):
         localdata = bb.data.createCopy(e.data)
diff --git a/meta/conf/bitbake.conf b/meta/conf/bitbake.conf
index 8e4f4bb..6b5a195 100644
--- a/meta/conf/bitbake.conf
+++ b/meta/conf/bitbake.conf
@@ -477,6 +477,10 @@ HOSTTOOLS_NONFATAL += "aws ccache gcc-ar gpg ld.bfd ld.gold nc sftp socat sudo"
# Temporary add few more detected in bitbake world
HOSTTOOLS_NONFATAL += "join nl size yes zcat"
+# Tools that can occasionally cause problems at runtime if they aren't present
+# on the host.
+HOSTTOOLS_OPTIONAL += "svn cvs bzr hg"
+
CCACHE ??= ""
# Disable ccache explicitly if CCACHE is null since gcc may be a symlink
# of ccache some distributions (e.g., Fedora 17).
diff --git a/meta/files/warnmissing.sh b/meta/files/warnmissing.sh
new file mode 100755
index 0000000..0048af4
--- /dev/null
+++ b/meta/files/warnmissing.sh
@@ -0,0 +1,2 @@
+echo "The following tool (as specified by HOSTTOOLS_OPTIONAL) appears to be unavailable in PATH but is needed by one or more recipes. Please install it in order to proceed:\n  `basename $0`"
+exit 1
--
2.7.4

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openembedded.org/pipermail/openembedded-core/attachments/20170523/822f0162/attachment-0002.html>