update-alternatives.bbclass: Refactor the implementation

Refactor in order to:
  * Deprecate the old interfaces, but keep them for compatibility
  * Provide a new, interface -- capable of working with split packages
  * Each update-alternative will now set proper "per-file" provides

Note: this adds a warning message when the older deprecated behavior is
used.  The older behavior has been fully tested using oe-core.

(From OE-Core rev: 309117d26de6a87b16406a44a0cefcbaaf7b5d7a)

Signed-off-by: Mark Hatle <mark.hatle@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 283 insertions, 61 deletions

diff --git a/meta/classes/update-alternatives.bbclass b/meta/classes/update-alternatives.bbclass
index 7b0518d848..e235299a5b 100644
--- a/meta/classes/update-alternatives.bbclass
+++ b/meta/classes/update-alternatives.bbclass
@@ -3,6 +3,68 @@
 # command directly in your recipe, but in most cases this class simplifies
 # that job.
 #
+# To use this class a number of variables should be defined:
+#
+# List all of the alternatives needed by a package:
+# ALTERNATIVE_<pkg> = "name1 name2 name3 ..."
+#
+#   i.e. ALTERNATIVE_busybox = "sh sed test bracket"
+#
+# The pathname of the link
+# ALTERNATIVE_LINK_NAME[name] = "target"
+#
+#   This is the name of the binary once it's been installed onto the runtime.
+#   This name is global to all split packages in this recipe, and should match
+#   other recipes with the same functionality.
+#   i.e. ALTERNATIVE_LINK_NAME[bracket] = "/usr/bin/["
+#
+# NOTE: If ALTERNATIVE_LINK_NAME is not defined, it defaults to ${bindir}/name
+#
+# The default link to create for all targets
+# ALTERNATIVE_TARGET = "target"
+#
+#   This is useful in a multicall binary case
+#   i.e. ALTERNATIVE_TARGET = "/bin/busybox"
+#
+# A non-default link to create for a target
+# ALTERNATIVE_TARGET[name] = "target"
+#
+#   This is the name of the binary as it's been install by do_install
+#   i.e. ALTERNATIVE_TARGET[sh] = "/bin/bash"
+#
+# A package specific link for a target
+# ALTERNATIVE_TARGET_<pkg>[name] = "target"
+#
+#   This is useful when a recipe provides multiple alternatives for the
+#   same item.
+#
+# NOTE: If ALTERNATIVE_TARGET is not defined, it will inherit the value
+# from ALTERNATIVE_LINK_NAME.
+#
+# NOTE: If the ALTERNATIVE_LINK_NAME and ALTERNATIVE_TARGET are the same,
+# ALTERNATIVE_TARGET will have '.{PN}' appended to it.  If the file
+# referenced has not been renamed, it will also be renamed.  (This avoids
+# the need to rename alternative files in the do_install step, but still
+# supports it if necessary for some reason.)
+#
+# The default priority for any alternatives
+# ALTERNATIVE_PRIORITY = "priority"
+#
+#   i.e. default is ALTERNATIVE_PRIORITY = "10"
+#
+# The non-default priority for a specific target
+# ALTERNATIVE_PRIORITY[name] = "priority"
+#
+# The package priority for a specific target
+# ALTERNATIVE_PRIORITY_<pkg>[name] = "priority"
+#
+#
+# -----
+#
+#
+# The following describes deprecated behavior, using any of the
+# following modes will result in a warning, and eventually an error:
+#
 # There are two basic modes supported: 'single update' and 'batch update'
 #
 # 'single update' is used for a single alternative command, and you're
@@ -38,79 +100,239 @@
 
 # defaults
 ALTERNATIVE_PRIORITY = "10"
-ALTERNATIVE_LINK = "${bindir}/${ALTERNATIVE_NAME}"
-
-update_alternatives_postinst() {
-update-alternatives --install ${ALTERNATIVE_LINK} ${ALTERNATIVE_NAME} ${ALTERNATIVE_PATH} ${ALTERNATIVE_PRIORITY}
-}
-
-update_alternatives_postrm() {
-update-alternatives --remove ${ALTERNATIVE_NAME} ${ALTERNATIVE_PATH}
-}
-
-# for batch alternatives, we use a simple approach to require only one parameter
-# with the rest of the info deduced implicitly
-update_alternatives_batch_postinst() {
-for link in ${ALTERNATIVE_LINKS}
-do
-        name=`basename ${link}`
-        path=${link}.${PN}
-        update-alternatives --install ${link} ${name} ${path} ${ALTERNATIVE_PRIORITY}
-done
-}
-
-update_alternatives_batch_postrm() {
-for link in ${ALTERNATIVE_LINKS}
-do
-        name=`basename ${link}`
-        path=${link}.${PN}
-        update-alternatives --remove ${name} $path
-done
-}
-
-update_alternatives_batch_doinstall() {
-        for link in ${ALTERNATIVE_LINKS}
-        do
-                mv ${D}${link} ${D}${link}.${PN}
-        done
-}
 
+# The following code is deprecated, but included for compatibility with older packages
 def update_alternatives_after_parse(d):
     if bb.data.inherits_class('native', d) or bb.data.inherits_class('nativesdk', d):
         return
 
+    # The following code is deprecated, but included for compatibility with older packages
+    pn = d.getVar('PN', True)
+
     if d.getVar('ALTERNATIVE_LINKS') != None:
-        doinstall = d.getVar('do_install', 0)
-        doinstall += d.getVar('update_alternatives_batch_doinstall', 0)
-        d.setVar('do_install', doinstall)
+        # Convert old format to new format...
+        alt_links = d.getVar('ALTERNATIVE_LINKS', True) or ""
+        for alt_link in alt_links.split():
+                alt_name = os.path.basename(alt_link)
+
+                alternative = d.getVar('ALTERNATIVE_%s' % pn, True) or ""
+                alternative += " " + alt_name
+                d.setVar('ALTERNATIVE_%s' % pn, alternative)
+                d.setVarFlag('ALTERNATIVE_LINK_NAME', alt_name, alt_link)
+                d.setVarFlag('ALTERNATIVE_TARGET', alt_name, alt_link)
         return
 
-    if d.getVar('ALTERNATIVE_NAME') == None:
-        raise bb.build.FuncFailed, "%s inherits update-alternatives but doesn't set ALTERNATIVE_NAME" % d.getVar('FILE')
-    if d.getVar('ALTERNATIVE_PATH') == None:
-        raise bb.build.FuncFailed, "%s inherits update-alternatives but doesn't set ALTERNATIVE_PATH" % d.getVar('FILE')
+    if d.getVar('ALTERNATIVE_NAME') != None or d.getVar('ALTERNATIVE_PATH') != None:
+        # Convert old format to new format...
+        alt_name = d.getVar('ALTERNATIVE_NAME', True)
+        alt_path = d.getVar('ALTERNATIVE_PATH', True)
+        alt_link = d.getVar('ALTERNATIVE_LINK', True) or ("%s/%s" % (d.getVar('bindir', True), alt_name))
+        if alt_name == None:
+                raise bb.build.build.FuncFailed, "%s inherits update-alternatives but doesn't set ALTERNATIVE_NAME" % d.getVar('FILE')
+        if alt_path == None:
+                raise bb.build.build.FuncFailed, "%s inherits update-alternatives but doesn't set ALTERNATIVE_PATH" % d.getVar('FILE')
+
+        alternative = d.getVar('ALTERNATIVE_%s' % pn, True) or ""
+        alternative += " " + alt_name
+
+        # Fix the alt_path if it's relative
+        alt_path = os.path.join(os.path.dirname(alt_link), alt_path)
+
+        d.setVar('ALTERNATIVE_%s' % pn, alternative)
+        d.setVarFlag('ALTERNATIVE_LINK_NAME', alt_name, alt_link)
+        d.setVarFlag('ALTERNATIVE_TARGET', alt_name, alt_path)
+
+
+# We need special processing for vardeps because it can not work on
+# modified flag values.  So we agregate the flags into a new variable
+# and include that vairable in the set.
+
+UPDALTVARS  = "ALTERNATIVE ALTERNATIVE_LINK_NAME ALTERNATIVE_TARGET ALTERNATIVE_PRIORITY"
+
+def gen_updatealternativesvardeps(d):
+   pkgs = (d.getVar("PACKAGES", True) or "").split()
+   vars = (d.getVar("UPDALTVARS", True) or "").split()
+
+   # First compute them for non_pkg versions
+   for v in vars:
+      for flag in (d.getVarFlags(v) or {}):
+         if flag == "doc" or flag == "vardeps" or flag == "vardepsexp":
+            continue
+         d.appendVar('%s_VARDEPS' % (v), ' %s:%s' % (flag, d.getVarFlag(v, flag, False)))
+
+   for p in pkgs:
+      for v in vars:
+         for flag in (d.getVarFlags("%s_%s" % (v,p)) or {}):
+            if flag == "doc" or flag == "vardeps" or flag == "vardepsexp":
+               continue
+            d.appendVar('%s_VARDEPS_%s' % (v,p), ' %s:%s' % (flag, d.getVarFlag('%s_%s' % (v,p), flag, False)))
 
 python __anonymous() {
+    # deprecated stuff...
     update_alternatives_after_parse(d)
+
+    # compute special vardeps
+    gen_updatealternativesvardeps(d)
+}
+
+def gen_updatealternativesvars(d):
+   ret = []
+   pkgs = (d.getVar("PACKAGES", True) or "").split()
+   vars = (d.getVar("UPDALTVARS", True) or "").split()
+
+   for v in vars:
+      ret.append(v + "_VARDEPS")
+
+   for p in pkgs:
+      for v in vars:
+         ret.append(v + "_" + p)
+         ret.append(v + "_VARDEPS_" + p)
+   return " ".join(ret)
+
+# First the deprecated items...
+populate_packages[vardeps] += "ALTERNATIVE_LINKS ALTERNATIVE_NAME ALTERNATIVE_PATH"
+
+# Now the new stuff, we use a custom function to generate the right values
+populate_packages[vardeps] += "${UPDALTVARS} ${@gen_updatealternativesvars(d)}"
+
+# We need to do the rename after the image creation step, but before
+# the split and strip steps..  packagecopy seems to be the earliest reasonable
+# place.
+python perform_packagecopy_append () {
+        # Check for deprecated usage...
+        pn = d.getVar('PN', True)
+        if d.getVar('ALTERNATIVE_LINKS', True) != None:
+                bb.warn('%s: Use of ALTERNATIVE_LINKS is deprecated, see update-alternatives.bbclass for more info.' % pn)
+
+        if d.getVar('ALTERNATIVE_NAME', True) != None or d.getVar('ALTERNATIVE_PATH', True) != None:
+                bb.warn('%s: Use of ALTERNATIVE_NAME is deprecated, see update-alternatives.bbclass for more info.' % pn)
+
+        # Do actual update alternatives processing
+        pkgdest = d.getVar('PKGD', True)
+        for pkg in (d.getVar('PACKAGES', True) or "").split():
+                # If the src == dest, we know we need to rename the dest by appending ${PN}
+                link_rename = {}
+                for alt_name in (d.getVar('ALTERNATIVE_%s' % pkg, True) or "").split():
+                        alt_link     = d.getVarFlag('ALTERNATIVE_LINK_NAME', alt_name, True)
+                        if not alt_link:
+                                alt_link = "%s/%s" % (d.getVar('bindir', True), alt_name)
+                                d.setVarFlag('ALTERNATIVE_LINK_NAME', alt_name, alt_link)
+
+                        alt_target   = d.getVarFlag('ALTERNATIVE_TARGET_%s' % pkg, alt_name, True) or d.getVarFlag('ALTERNATIVE_TARGET', alt_name, True)
+                        alt_target   = alt_target or d.getVar('ALTERNATIVE_TARGET_%s' % pkg, True) or d.getVar('ALTERNATIVE_TARGET', True) or alt_link
+                        # Sometimes alt_target is specified as relative to the link name.
+                        alt_target   = os.path.join(os.path.dirname(alt_link), alt_target)
+
+                        # If the link and target are the same name, we need to rename the target.
+                        if alt_link == alt_target:
+                                src = '%s/%s' % (pkgdest, alt_target)
+                                alt_target_rename = '%s.%s' % (alt_target, pn)
+                                dest = '%s/%s' % (pkgdest, alt_target_rename)
+                                if os.path.lexists(dest):
+                                        bb.note('%s: Already renamed: %s' % (pn, alt_target_rename))
+                                elif os.path.lexists(src):
+                                        if os.path.islink(src):
+                                                # Delay rename of links
+                                                link_rename[alt_target] = alt_target_rename
+                                        else:
+                                                bb.note('%s: Rename %s -> %s' % (pn, alt_target, alt_target_rename))
+                                                os.rename(src, dest)
+                                else:
+                                        bb.warn("%s: alternative target (%s or %s) does not exist, skipping..." % (pn, alt_target, alt_target_rename))
+                                        continue
+                                d.setVarFlag('ALTERNATIVE_TARGET_%s' % pkg, alt_name, alt_target_rename)
+
+                # Process delayed link names
+                # Do these after other renames so we can correct broken links
+                for alt_target in link_rename:
+                        src = '%s/%s' % (pkgdest, alt_target)
+                        dest = '%s/%s' % (pkgdest, link_rename[alt_target])
+                        link_target = os.path.join(os.path.dirname(src), os.readlink(src))
+
+                        if os.path.lexists(link_target):
+                                # Ok, the link_target exists, we can rename
+                                bb.note('%s: Rename (link) %s -> %s' % (pn, alt_target, link_rename[alt_target]))
+                                os.rename(src, dest)
+                        else:
+                                # Try to resolve the broken link to link.${PN}
+                                link_maybe = '%s.%s' % (os.readlink(src), pn)
+                                if os.path.lexists(os.path.join(os.path.dirname(src), link_maybe)):
+                                        # Ok, the renamed link target exists.. create a new link, and remove the original
+                                        bb.note('%s: Creating new link %s -> %s' % (pn, link_rename[alt_target], link_maybe))
+                                        os.symlink(link_maybe, dest)
+                                        os.unlink(src)
+                                else:
+                                        bb.warn('%s: Unable to resolve dangling symlink: %s' % (pn, alt_target))
 }
 
 python populate_packages_prepend () {
-        pkg = d.getVar('PN', True)
-        bb.note('adding update-alternatives calls to postinst/postrm for %s' % pkg)
-        postinst = d.getVar('pkg_postinst_%s' % pkg, True) or d.getVar('pkg_postinst', True)
-        if not postinst:
-                postinst = '#!/bin/sh\n'
-        if d.getVar('ALTERNATIVE_LINKS') != None:
-                postinst += d.getVar('update_alternatives_batch_postinst', True)
-        else:
-                postinst += d.getVar('update_alternatives_postinst', True)
-        d.setVar('pkg_postinst_%s' % pkg, postinst)
-        postrm = d.getVar('pkg_postrm_%s' % pkg, True) or d.getVar('pkg_postrm', True)
-        if not postrm:
-                postrm = '#!/bin/sh\n'
-        if d.getVar('ALTERNATIVE_LINKS') != None:
-                postrm += d.getVar('update_alternatives_batch_postrm', True)
-        else:
-                postrm += d.getVar('update_alternatives_postrm', True)
-        d.setVar('pkg_postrm_%s' % pkg, postrm)
+        pn = d.getVar('BPN', True)
+
+        # Do actual update alternatives processing
+        pkgdest = d.getVar('PKGD', True)
+        for pkg in (d.getVar('PACKAGES', True) or "").split():
+                # Create post install/removal scripts
+                alt_setup_links = ""
+                alt_remove_links = ""
+                for alt_name in (d.getVar('ALTERNATIVE_%s' % pkg, True) or "").split():
+                        alt_link     = d.getVarFlag('ALTERNATIVE_LINK_NAME', alt_name, True)
+                        alt_target   = d.getVarFlag('ALTERNATIVE_TARGET_%s' % pkg, alt_name, True) or d.getVarFlag('ALTERNATIVE_TARGET', alt_name, True)
+                        alt_target   = alt_target or d.getVar('ALTERNATIVE_TARGET_%s' % pkg, True) or d.getVar('ALTERNATIVE_TARGET', True) or alt_link
+                        # Sometimes alt_target is specified as relative to the link name.
+                        alt_target   = os.path.join(os.path.dirname(alt_link), alt_target)
+
+                        alt_priority = d.getVarFlag('ALTERNATIVE_PRIORITY_%s' % pkg,  alt_name, True) or d.getVarFlag('ALTERNATIVE_PRIORITY',  alt_name, True)
+                        alt_priority = alt_priority or d.getVar('ALTERNATIVE_PRIORITY_%s' % pkg, True) or d.getVar('ALTERNATIVE_PRIORITY', True)
+
+                        # This shouldn't trigger, as it should have been resolved earlier!
+                        if alt_link == alt_target:
+                                bb.note('alt_link == alt_target: %s == %s -- correcting, this should not happen!' % (alt_link, alt_target))
+                                alt_target = '%s.%s' % (alt_target, pn)
+
+                        if not os.path.lexists('%s/%s' % (pkgdest, alt_target)):
+                                bb.warn('%s: NOT adding alternative provide %s: %s does not exist' % (pn, alt_link, alt_target))
+                                continue
+
+                        # Default to generate shell script.. eventually we may want to change this...
+                        alt_target = os.path.relpath(alt_target, os.path.dirname(alt_link))
+
+                        alt_setup_links  += '   update-alternatives --install %s %s %s %s\n' % (alt_link, alt_name, alt_target, alt_priority)
+                        alt_remove_links += '   update-alternatives --remove  %s %s\n' % (alt_name, alt_target)
+
+                if alt_setup_links:
+                        bb.note('adding update-alternatives calls to postinst/postrm for %s' % pkg)
+                        bb.note('%s' % alt_setup_links)
+                        postinst = (d.getVar('pkg_postinst_%s' % pkg, True) or d.getVar('pkg_postinst', True)) or '#!/bin/sh\n'
+                        postinst += alt_setup_links
+                        d.setVar('pkg_postinst_%s' % pkg, postinst)
+
+                        bb.note('%s' % alt_remove_links)
+                        postrm = (d.getVar('pkg_postrm_%s' % pkg, True) or d.getVar('pkg_postrm', True)) or '#!/bin/sh\n'
+                        postrm += alt_remove_links
+                        d.setVar('pkg_postrm_%s' % pkg, postrm)
 }
+
+python package_do_filedeps_append () {
+        pn = d.getVar('PN', True)
+        pkgdest = d.getVar('PKGDEST', True)
+
+        for pkg in packages.split():
+                for alt_name in (d.getVar('ALTERNATIVE_%s' % pkg, True) or "").split():
+                        alt_link     = d.getVarFlag('ALTERNATIVE_LINK_NAME', alt_name, True)
+                        alt_target   = d.getVarFlag('ALTERNATIVE_TARGET_%s' % pkg, alt_name, True) or d.getVarFlag('ALTERNATIVE_TARGET', alt_name, True)
+                        alt_target   = alt_target or d.getVar('ALTERNATIVE_TARGET_%s' % pkg, True) or d.getVar('ALTERNATIVE_TARGET', True) or alt_link
+
+                        if alt_link == alt_target:
+                                bb.warn('alt_link == alt_target: %s == %s' % (alt_link, alt_target))
+                                alt_target = '%s.%s' % (alt_target, pn)
+
+                        if not os.path.lexists('%s/%s/%s' % (pkgdest, pkg, alt_target)):
+                                continue
+
+                        # Add file provide
+                        trans_target = file_translate(alt_target)
+                        d.appendVar('FILERPROVIDES_%s_%s' % (trans_target, pkg), " " + alt_link)
+                        if not trans_target in (d.getVar('FILERPROVIDESFLIST_%s' % pkg, True) or ""):
+                                d.appendVar('FILERPROVIDESFLIST_%s' % pkg, " " + trans_target)
+}
+