Keep sticky requirement of super-sticky module on forced purge

On a forced purge, a sticky module required by a retained super-sticky
module got a "forced unload" warning immediately followed by the error
reporting its unload is skipped as a super-sticky requirement. The
module stayed loaded, but the sticky check reported the forced unload
before the requirement check retained the module.

Check whether a module is required by a retained sticky module as part
of the sticky check itself, prior reporting the forced unload of a
sticky module. Rely on the existing sticky module test to determine if
a sticky dependent is retained rather than duplicating this rule.

Assisted-by: Claude:claude-fable-5-1
Signed-off-by: Xavier Delaruelle <xavier.delaruelle@cea.fr>

Author: xdelaruelle

tcl/modeval.tcl

@@ -965,7 +965,7 @@ proc getModuleStickyDependentTag {mod} {
       if {[isModuleTagged $dep_mod super-sticky 1]} {
          set sticky_tag super-sticky
          break
-      } elseif {![getState force] && [isModuleTagged $dep_mod sticky 1]} {
+      } elseif {[isModuleSticky $dep_mod]} {
          set sticky_tag sticky
       }
    }
@@ -1166,10 +1166,8 @@ proc failOrSkipUnloadIfSticky {modname modfile} {
    set sticky_purge [expr {[getState commandname] eq {purge} ? [getConf\
       sticky_purge] : {}}]
 
-   if {!$is_supersticky_not_reloading && $is_sticky_not_reloading &&\
-      [getState force]} {
-      reportWarning [getStickyForcedUnloadMsg]
-   } elseif {$is_supersticky_not_reloading || $is_sticky_not_reloading} {
+   if {$is_supersticky_not_reloading || ($is_sticky_not_reloading &&\
+      ![getState force])} {
       set msg [getStickyUnloadMsg [expr {$is_supersticky_not_reloading ?\
          {super-sticky} : {sticky}}]]
       # no message if sticky_purge is set to silent
@@ -1182,6 +1180,17 @@ proc failOrSkipUnloadIfSticky {modname modfile} {
       return 1
    }
 
+   # on purge, module required by a retained sticky module is kept loaded,
+   # which prevails over the forced unload of a sticky module
+   if {$sticky_purge ne {} && [failOrSkipUnloadIfRequiredBySticky\
+      $modname]} {
+      return 1
+   }
+
+   if {$is_sticky_not_reloading && [getState force]} {
+      reportWarning [getStickyForcedUnloadMsg]
+   }
+
    return 0
 }
 

tcl/subcmd.tcl.in

@@ -1577,11 +1577,6 @@ proc cmdModuleUnload {context match auto force onlyureq args} {
          set prereq_list [getDependentLoadedModuleList [list $modname]]
          set prereq_loaded_list [getDependentLoadedModuleList [list $modname]\
             1 1 0 0]
-         if {[llength $prereq_loaded_list] &&\
-            [getState commandname] eq {purge} &&\
-            [failOrSkipUnloadIfRequiredBySticky $modname]} {
-            continue
-         }
          if {[llength $prereq_loaded_list] && (![getConf auto_handling] ||\
             !$auto)} {
             # force mode should not affect if we only look for mods w/o dep

testsuite/modules.50-cmds/464-sticky_purge.exp

@@ -218,6 +218,42 @@ foreach {tag2 tag3 msg2 msg3} [list sticky super-sticky\
 unsetenv_var __MODULES_LMPREREQ
 
 
+# sticky requirement of super-sticky module is kept on forced purge
+setenv_var TESTSUITE_STICKY purge_req
+setenv_loaded_module [list sticky1/1.0 sticky2/1.0] [list\
+    $mp/sticky1/1.0 $mp/sticky2/1.0]
+setenv_var __MODULES_LMTAG sticky1/1.0&sticky:sticky2/1.0&super-sticky
+setenv_var __MODULES_LMPREREQ sticky2/1.0&sticky1/1.0|sticky1/2.0
+foreach {report_mode msg reqmsg stickymsg} [list error\
+    $err_superstickyunload $err_superstickyrequnload $err_stickyunload\
+    warning $warn_superstickyunload $warn_superstickyrequnload\
+    $warn_stickyunload silent {} {} {}] {
+    setenv_var MODULES_STICKY_PURGE $report_mode
+    set ans [list]
+    if {$report_mode eq {error}} {
+        lappend ans [list ERR]
+    }
+    set tserr {}
+    if {$report_mode ne {silent}} {
+        set tserr [msg_unload {sticky2/1.0 <sS>} $msg]\n\n[msg_unload\
+            {sticky1/1.0 <S>} $stickymsg]
+    }
+    testouterr_cmd sh {purge} $ans $tserr
+
+    # requirement is retained, so no forced unload warning
+    set tserr {}
+    if {$report_mode ne {silent}} {
+        set tserr [msg_unload {sticky2/1.0 <sS>} $msg]\n\n[msg_unload\
+            {sticky1/1.0 <S>} $reqmsg]
+    }
+    testouterr_cmd sh {purge -f} $ans $tserr
+}
+
+
+unsetenv_var __MODULES_LMPREREQ
+unsetenv_var TESTSUITE_STICKY
+
+
 # module both sticky and super-sticky
 setenv_var TESTSUITE_FPMOD_TAG sticky2
 setenv_loaded_module [list foo/1.0 tag/1.0] [list $mp/foo/1.0 $mp/tag/1.0]