Shared: use getToken instead of getLastToken

asgerf · asgerf · commit d911e0abf88b · 2022-02-21T08:21:52.000+01:00
diff --git a/java/ql/lib/semmle/code/java/dataflow/internal/FlowSummaryImpl.qll b/java/ql/lib/semmle/code/java/dataflow/internal/FlowSummaryImpl.qll
@@ -846,24 +846,26 @@ module Private {
      * Holds if `spec` specifies summary component stack `stack`.
      */
     predicate interpretSpec(AccessPath spec, SummaryComponentStack stack) {
-      interpretSpec(spec, 0, stack)
+      interpretSpec(spec, spec.getNumToken(), stack)
     }
 
-    private predicate interpretSpec(AccessPath spec, int idx, SummaryComponentStack stack) {
-      idx = spec.getNumToken() - 1 and
-      stack = SummaryComponentStack::singleton(interpretComponent(spec.getLastToken(idx)))
+    /** Holds if the first `n` tokens of `spec` resolves to `stack`. */
+    private predicate interpretSpec(AccessPath spec, int n, SummaryComponentStack stack) {
+      n = 1 and
+      stack = SummaryComponentStack::singleton(interpretComponent(spec.getToken(0)))
       or
       exists(SummaryComponent head, SummaryComponentStack tail |
-        interpretSpec(spec, idx, head, tail) and
+        interpretSpec(spec, n, head, tail) and
         stack = SummaryComponentStack::push(head, tail)
       )
     }
 
+    /** Holds if the first `n` tokens of `spec` resolves to `head` followed by `tail` */
     private predicate interpretSpec(
-      AccessPath output, int idx, SummaryComponent head, SummaryComponentStack tail
+      AccessPath spec, int n, SummaryComponent head, SummaryComponentStack tail
     ) {
-      interpretSpec(output, idx + 1, tail) and
-      head = interpretComponent(output.getLastToken(idx))
+      interpretSpec(spec, n - 1, tail) and
+      head = interpretComponent(spec.getToken(n - 1))
     }
 
     private class MkStack extends RequiredSummaryComponentStack {
@@ -924,11 +926,12 @@ module Private {
       )
     }
 
+    /** Holds if the first `n` tokens of `output` resolve to the given interpretation. */
     private predicate interpretOutput(
-      AccessPath output, int idx, InterpretNode ref, InterpretNode node
+      AccessPath output, int n, InterpretNode ref, InterpretNode node
     ) {
       sourceElementRef(ref, output, _) and
-      idx = output.getNumToken() and
+      n = 0 and
       (
         if output = ""
         then
@@ -938,8 +941,8 @@ module Private {
       )
       or
       exists(InterpretNode mid, AccessPathToken c |
-        interpretOutput(output, idx + 1, ref, mid) and
-        c = output.getLastToken(idx)
+        interpretOutput(output, n - 1, ref, mid) and
+        c = output.getToken(n - 1)
       |
         exists(ArgumentPosition apos, ParameterPosition ppos |
           node.asNode().(PostUpdateNode).getPreUpdateNode().(ArgNode).argumentOf(mid.asCall(), apos) and
@@ -962,11 +965,12 @@ module Private {
       )
     }
 
+    /** Holds if the first `n` tokens of `input` resolve to the given interpretation. */
     private predicate interpretInput(
-      AccessPath input, int idx, InterpretNode ref, InterpretNode node
+      AccessPath input, int n, InterpretNode ref, InterpretNode node
     ) {
       sinkElementRef(ref, input, _) and
-      idx = input.getNumToken() and
+      n = 0 and
       (
         if input = ""
         then
@@ -976,8 +980,8 @@ module Private {
       )
       or
       exists(InterpretNode mid, AccessPathToken c |
-        interpretInput(input, idx + 1, ref, mid) and
-        c = input.getLastToken(idx)
+        interpretInput(input, n - 1, ref, mid) and
+        c = input.getToken(n - 1)
       |
         exists(ArgumentPosition apos, ParameterPosition ppos |
           node.asNode().(ArgNode).argumentOf(mid.asCall(), apos) and
@@ -1002,9 +1006,9 @@ module Private {
      * model.
      */
     predicate isSourceNode(InterpretNode node, string kind) {
-      exists(InterpretNode ref, string output |
+      exists(InterpretNode ref, AccessPath output |
         sourceElementRef(ref, output, kind) and
-        interpretOutput(output, 0, ref, node)
+        interpretOutput(output, output.getNumToken(), ref, node)
       )
     }
 
@@ -1013,9 +1017,9 @@ module Private {
      * model.
      */
     predicate isSinkNode(InterpretNode node, string kind) {
-      exists(InterpretNode ref, string input |
+      exists(InterpretNode ref, AccessPath input |
         sinkElementRef(ref, input, kind) and
-        interpretInput(input, 0, ref, node)
+        interpretInput(input, input.getNumToken(), ref, node)
       )
     }
   }

Original file line number	Diff line number	Diff line change
`@@ -846,24 +846,26 @@ module Private {`
`846`	`846`	* Holds if `spec` specifies summary component stack `stack`.
`847`	`847`	`*/`
`848`	`848`	`predicate interpretSpec(AccessPath spec, SummaryComponentStack stack) {`
`849`		`- interpretSpec(spec, 0, stack)`
	`849`	`+ interpretSpec(spec, spec.getNumToken(), stack)`
`850`	`850`	`}`
`851`	`851`
`852`		`- private predicate interpretSpec(AccessPath spec, int idx, SummaryComponentStack stack) {`
`853`		`- idx = spec.getNumToken() - 1 and`
`854`		`- stack = SummaryComponentStack::singleton(interpretComponent(spec.getLastToken(idx)))`
	`852`	+ /** Holds if the first `n` tokens of `spec` resolves to `stack`. */
	`853`	`+ private predicate interpretSpec(AccessPath spec, int n, SummaryComponentStack stack) {`
	`854`	`+ n = 1 and`
	`855`	`+ stack = SummaryComponentStack::singleton(interpretComponent(spec.getToken(0)))`
`855`	`856`	`or`
`856`	`857`	`exists(SummaryComponent head, SummaryComponentStack tail \|`
`857`		`- interpretSpec(spec, idx, head, tail) and`
	`858`	`+ interpretSpec(spec, n, head, tail) and`
`858`	`859`	`stack = SummaryComponentStack::push(head, tail)`
`859`	`860`	`)`
`860`	`861`	`}`
`861`	`862`
	`863`	+ /** Holds if the first `n` tokens of `spec` resolves to `head` followed by `tail` */
`862`	`864`	`private predicate interpretSpec(`
`863`		`- AccessPath output, int idx, SummaryComponent head, SummaryComponentStack tail`
	`865`	`+ AccessPath spec, int n, SummaryComponent head, SummaryComponentStack tail`
`864`	`866`	`) {`
`865`		`- interpretSpec(output, idx + 1, tail) and`
`866`		`- head = interpretComponent(output.getLastToken(idx))`
	`867`	`+ interpretSpec(spec, n - 1, tail) and`
	`868`	`+ head = interpretComponent(spec.getToken(n - 1))`
`867`	`869`	`}`
`868`	`870`
`869`	`871`	`private class MkStack extends RequiredSummaryComponentStack {`
`@@ -924,11 +926,12 @@ module Private {`
`924`	`926`	`)`
`925`	`927`	`}`
`926`	`928`
	`929`	+ /** Holds if the first `n` tokens of `output` resolve to the given interpretation. */
`927`	`930`	`private predicate interpretOutput(`
`928`		`- AccessPath output, int idx, InterpretNode ref, InterpretNode node`
	`931`	`+ AccessPath output, int n, InterpretNode ref, InterpretNode node`
`929`	`932`	`) {`
`930`	`933`	`sourceElementRef(ref, output, _) and`
`931`		`- idx = output.getNumToken() and`
	`934`	`+ n = 0 and`
`932`	`935`	`(`
`933`	`936`	`if output = ""`
`934`	`937`	`then`
`@@ -938,8 +941,8 @@ module Private {`
`938`	`941`	`)`
`939`	`942`	`or`
`940`	`943`	`exists(InterpretNode mid, AccessPathToken c \|`
`941`		`- interpretOutput(output, idx + 1, ref, mid) and`
`942`		`- c = output.getLastToken(idx)`
	`944`	`+ interpretOutput(output, n - 1, ref, mid) and`
	`945`	`+ c = output.getToken(n - 1)`
`943`	`946`	`\|`
`944`	`947`	`exists(ArgumentPosition apos, ParameterPosition ppos \|`
`945`	`948`	`node.asNode().(PostUpdateNode).getPreUpdateNode().(ArgNode).argumentOf(mid.asCall(), apos) and`
`@@ -962,11 +965,12 @@ module Private {`
`962`	`965`	`)`
`963`	`966`	`}`
`964`	`967`
	`968`	+ /** Holds if the first `n` tokens of `input` resolve to the given interpretation. */
`965`	`969`	`private predicate interpretInput(`
`966`		`- AccessPath input, int idx, InterpretNode ref, InterpretNode node`
	`970`	`+ AccessPath input, int n, InterpretNode ref, InterpretNode node`
`967`	`971`	`) {`
`968`	`972`	`sinkElementRef(ref, input, _) and`
`969`		`- idx = input.getNumToken() and`
	`973`	`+ n = 0 and`
`970`	`974`	`(`
`971`	`975`	`if input = ""`
`972`	`976`	`then`
`@@ -976,8 +980,8 @@ module Private {`
`976`	`980`	`)`
`977`	`981`	`or`
`978`	`982`	`exists(InterpretNode mid, AccessPathToken c \|`
`979`		`- interpretInput(input, idx + 1, ref, mid) and`
`980`		`- c = input.getLastToken(idx)`
	`983`	`+ interpretInput(input, n - 1, ref, mid) and`
	`984`	`+ c = input.getToken(n - 1)`
`981`	`985`	`\|`
`982`	`986`	`exists(ArgumentPosition apos, ParameterPosition ppos \|`
`983`	`987`	`node.asNode().(ArgNode).argumentOf(mid.asCall(), apos) and`
`@@ -1002,9 +1006,9 @@ module Private {`
`1002`	`1006`	`* model.`
`1003`	`1007`	`*/`
`1004`	`1008`	`predicate isSourceNode(InterpretNode node, string kind) {`
`1005`		`- exists(InterpretNode ref, string output \|`
	`1009`	`+ exists(InterpretNode ref, AccessPath output \|`
`1006`	`1010`	`sourceElementRef(ref, output, kind) and`
`1007`		`- interpretOutput(output, 0, ref, node)`
	`1011`	`+ interpretOutput(output, output.getNumToken(), ref, node)`
`1008`	`1012`	`)`
`1009`	`1013`	`}`
`1010`	`1014`
`@@ -1013,9 +1017,9 @@ module Private {`
`1013`	`1017`	`* model.`
`1014`	`1018`	`*/`
`1015`	`1019`	`predicate isSinkNode(InterpretNode node, string kind) {`
`1016`		`- exists(InterpretNode ref, string input \|`
	`1020`	`+ exists(InterpretNode ref, AccessPath input \|`
`1017`	`1021`	`sinkElementRef(ref, input, kind) and`
`1018`		`- interpretInput(input, 0, ref, node)`
	`1022`	`+ interpretInput(input, input.getNumToken(), ref, node)`
`1019`	`1023`	`)`
`1020`	`1024`	`}`
`1021`	`1025`	`}`