scripts/bitbake sanity.bbclass: Migrate tests for git and tar versions

Migrate tests for correct git and tar versions from the wrapper script
to the sanity class.

This sets the scene to allow us to remove the bitbake wrapper script.

(From OE-Core rev: 7b370e23594da5dcb53cd5507ec289c3ef2d9fb5)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/classes/sanity.bbclass

@@ -359,6 +359,28 @@ def check_gcc_march(sanity_data):
 
     return result
 
+# Tar version 1.24 and onwards handle overwriting symlinks correctly
+# but earlier versions do not; this needs to work properly for sstate
+def check_tar_version(sanity_data, loosever):
+    status, result = oe.utils.getstatusoutput("tar --version")
+    if status != 0:
+        return "Unable to execute tar --version, exit code %s\n" % status
+    version = result.split()[3]
+    if loosever(version) < loosever("1.24"):
+        return "Your version of tar is older than 1.24 and has bugs which will break builds. Please install a newer version of tar.\n"
+    return None
+
+# We use git parameters and functionality only found in 1.7.5 or later
+def check_git_version(sanity_data, loosever):
+    status, result = oe.utils.getstatusoutput("git --version 2> /dev/null")
+    if status != 0:
+        return "Unable to execute git --version, exit code %s\n" % status
+    version = result.split()[2]
+    if loosever(version) < loosever("1.7.5"):
+        return "Your version of git is older than 1.7.5 and has bugs which will break builds. Please install a newer version of git.\n"
+    return None
+
+
 def check_sanity(sanity_data):
     import subprocess
 
@@ -409,6 +431,15 @@ def check_sanity(sanity_data):
         messages = messages + 'Please set a MACHINE in your local.conf or environment\n'
         machinevalid = False
 
+    tarmsg = check_tar_version(sanity_data, LooseVersion)
+    if tarmsg:
+        messages = messages + tarmsg
+
+    gitmsg = check_git_version(sanity_data, LooseVersion)
+    if gitmsg:
+        messages = messages + gitmsg
+
+
     # Check we are using a valid local.conf
     current_conf  = sanity_data.getVar('CONF_VERSION', True)
     conf_version =  sanity_data.getVar('LOCALCONF_VERSION', True)