Added top_down evaluation order option

Ticket: ENT-10184
Signed-off-by: Victor Moene <victor.moene@northern.tech>

Author: victormlg

cf-agent/cf-agent.c

@@ -1559,6 +1559,15 @@ static void AllClassesReport(const EvalContext *ctx)
 
 PromiseResult ScheduleAgentOperations(EvalContext *ctx, const Bundle *bp)
 // NB - this function can be called recursively through "methods"
+{
+    if (EvalContextGetEvalOption(ctx, EVAL_OPTION_TOP_DOWN_EVALUATION))
+    {
+        return ScheduleAgentOperationsTopDownOrder(ctx, bp);
+    }
+    return ScheduleAgentOperationsNormalOrder(ctx, bp);
+}
+
+PromiseResult ScheduleAgentOperationsNormalOrder(EvalContext *ctx, const Bundle *bp)
 {
     assert(bp != NULL);
 
@@ -1652,6 +1661,59 @@ PromiseResult ScheduleAgentOperations(EvalContext *ctx, const Bundle *bp)
     return result;
 }
 
+PromiseResult ScheduleAgentOperationsTopDownOrder(EvalContext *ctx, const Bundle *bp)
+{
+    assert(bp != NULL);
+
+    int save_pr_kept = PR_KEPT;
+    int save_pr_repaired = PR_REPAIRED;
+    int save_pr_notkept = PR_NOTKEPT;
+    struct timespec start = BeginMeasure();
+
+    if (PROCESSREFRESH == NULL || (PROCESSREFRESH && IsRegexItemIn(ctx, PROCESSREFRESH, bp->name)))
+    {
+        ClearProcessTable();
+    }
+
+    // maybe 3 passes?
+    PromiseResult result = PROMISE_RESULT_SKIPPED;
+    const size_t sections = SeqLength(bp->all_sections);
+    EvalContextSetPass(ctx, 1);
+    for (size_t i = 0; i < sections; ++i)
+    {
+        BundleSection *section = SeqAt(bp->all_sections, i);
+
+        if (!section || SeqLength(section->promises) == 0)
+        {
+            continue;
+        }
+
+        SpecialTypeBannerFromString(section->promise_type, 1);
+        EvalContextStackPushBundleSectionFrame(ctx, section);
+
+        const size_t promises = SeqLength(section->promises);
+        for (size_t ppi = 0; ppi < promises; ppi++)
+        {
+            Promise *pp = SeqAt(section->promises, ppi);
+
+            
+            PromiseResult promise_result = ExpandPromise(ctx, pp, KeepAgentPromise, NULL);
+            result = PromiseResultUpdate(result, promise_result);
+            
+            if (EvalAborted(ctx) || BundleAbort(ctx))
+            {
+                EvalContextStackPopFrame(ctx);
+                NoteBundleCompliance(bp, save_pr_kept, save_pr_repaired, save_pr_notkept, start);
+                return result;
+            }
+        }
+        EvalContextStackPopFrame(ctx);
+    }
+
+    NoteBundleCompliance(bp, save_pr_kept, save_pr_repaired, save_pr_notkept, start);
+    return result;
+}
+
 /*********************************************************************/
 
 #ifdef __MINGW32__

libpromises/cf3.defs.h

@@ -441,6 +441,7 @@ typedef enum
     COMMON_CONTROL_TLS_MIN_VERSION,
     COMMON_CONTROL_PACKAGE_INVENTORY,
     COMMON_CONTROL_PACKAGE_MODULE,
+    COMMON_CONTROL_EVALUATION_ORDER,
     COMMON_CONTROL_MAX
 } CommonControl;
 

libpromises/eval_context.h

@@ -108,6 +108,7 @@ typedef enum
 
     EVAL_OPTION_EVAL_FUNCTIONS = 1 << 0,
     EVAL_OPTION_CACHE_SYSTEM_FUNCTIONS = 1 << 1,
+    EVAL_OPTION_TOP_DOWN_EVALUATION = 1 << 2,
 
     EVAL_OPTION_FULL = 0xFFFFFFFF
 } EvalContextOption;

libpromises/expand.c

@@ -1025,6 +1025,15 @@ static void ResolveControlBody(EvalContext *ctx, GenericAgentConfig *config,
             /* Ignored */
         }
 
+        if (strcmp(lval, CFG_CONTROLBODY[COMMON_CONTROL_EVALUATION_ORDER].lval) == 0)
+        {
+            Log(LOG_LEVEL_VERBOSE, "SET evaluation %s",
+                RvalScalarValue(evaluated_rval));
+
+            bool is_top_down = (StringEqual(RvalScalarValue(evaluated_rval), "top_down"));
+            EvalContextSetEvalOption(ctx, EVAL_OPTION_TOP_DOWN_EVALUATION, is_top_down);
+        }
+
         RvalDestroy(evaluated_rval);
     }
 

libpromises/mod_common.c

@@ -268,6 +268,7 @@ const ConstraintSyntax CFG_CONTROLBODY[COMMON_CONTROL_MAX + 1] =
     ConstraintSyntaxNewString("tls_min_version", "", "Minimum acceptable TLS version for outgoing connections, defaults to OpenSSL's default", SYNTAX_STATUS_NORMAL),
     ConstraintSyntaxNewStringList("package_inventory", ".*", "Name of the package manager used for software inventory management", SYNTAX_STATUS_NORMAL),
     ConstraintSyntaxNewString("package_module", ".*", "Name of the default package manager", SYNTAX_STATUS_NORMAL),
+    ConstraintSyntaxNewString("evaluation_order", "(normal|top_down)", "Order of evaluation of promises", SYNTAX_STATUS_NORMAL),
     ConstraintSyntaxNewNull()
 };
 

libpromises/ornaments.c

@@ -130,6 +130,20 @@ void SpecialTypeBanner(TypeSequence type, int pass)
     }
 }
 
+void SpecialTypeBannerFromString(char *type, int pass)
+{
+    if (StringEqual(type, "classes"))
+    {
+        Log(LOG_LEVEL_VERBOSE, "C: .........................................................");
+        Log(LOG_LEVEL_VERBOSE, "C: BEGIN classes / conditions (pass %d)", pass);
+    }
+    if (StringEqual(type, "vars"))
+    {
+        Log(LOG_LEVEL_VERBOSE, "V: .........................................................");
+        Log(LOG_LEVEL_VERBOSE, "V: BEGIN variables (pass %d)", pass);
+    }
+}
+
 void PromiseBanner(EvalContext *ctx, const Promise *pp)
 {
     char handle[CF_MAXVARSIZE];

libpromises/ornaments.h

@@ -34,6 +34,7 @@
 #include <eval_context.h>
 
 void SpecialTypeBanner(TypeSequence type, int pass);
+void SpecialTypeBannerFromString(char *type, int pass);
 void PromiseBanner(EvalContext *ctx, const Promise *pp);
 void Banner(const char *s);
 void Legend();

libpromises/policy.c

@@ -727,6 +727,7 @@ static bool PolicyCheckBundle(const Bundle *bundle, Seq *errors)
 
     success &= PolicyCheckBundleSections(bundle->sections, errors);
     success &= PolicyCheckBundleSections(bundle->custom_sections, errors);
+    success &= PolicyCheckBundleSections(bundle->all_sections, errors);
 
     return success;
 }
@@ -1322,6 +1323,7 @@ Bundle *PolicyAppendBundle(Policy *policy,
     bundle->source_path = SafeStringDuplicate(source_path);
     bundle->sections = SeqNew(10, BundleSectionDestroy);
     bundle->custom_sections = SeqNew(10, BundleSectionDestroy);
+    bundle->all_sections = SeqNew(10, NULL);
 
     return bundle;
 }
@@ -1427,6 +1429,7 @@ BundleSection *BundleAppendSection(Bundle *bundle, const char *promise_type)
     {
         SeqAppend(bundle->custom_sections, section);
     }
+    SeqAppend(bundle->all_sections, section);
 
     return section;
 }
@@ -1479,6 +1482,7 @@ static void BundleDestroy(Bundle *bundle)
         RlistDestroy(bundle->args);
         SeqDestroy(bundle->sections);
         SeqDestroy(bundle->custom_sections);
+        SeqDestroy(bundle->all_sections);
 
         free(bundle);
     }

libpromises/policy.h

@@ -79,6 +79,7 @@ struct Bundle_
 
     Seq *sections;
     Seq *custom_sections;
+    Seq *all_sections; // kinda wasting space?
 
     char *source_path;
     SourceOffset offset;

libpromises/prototypes3.h

@@ -44,6 +44,8 @@ void yyerror(const char *s);
 /* agent.c */
 
 PromiseResult ScheduleAgentOperations(EvalContext *ctx, const Bundle *bp);
+PromiseResult ScheduleAgentOperationsNormalOrder(EvalContext *ctx, const Bundle *bp);
+PromiseResult ScheduleAgentOperationsTopDownOrder(EvalContext *ctx, const Bundle *bp);
 
 /* Only for agent.c */