stability: clip oversized analyzer string matches

Author: yhs0602

app/src/main/java/com/kyhsgeekcode/disassembler/Analyzer.kt

@@ -15,6 +15,7 @@ import kotlin.math.exp
 import kotlin.math.ln
 import kotlin.math.pow
 
+private const val MAX_EMITTED_FOUND_STRING_CHARS = 4_096
 
 @ExperimentalUnsignedTypes
 class Analyzer(private val bytes: ByteArray) {
@@ -50,7 +51,18 @@ class Analyzer(private val bytes: ByteArray) {
                 val length = i - strstart
                 val offset = strstart
                 if (length in min..max) {
-                    val str = String(bytes, strstart, length)
+                    val previewLength = minOf(length, MAX_EMITTED_FOUND_STRING_CHARS)
+                    val str = String(bytes, strstart, previewLength).let {
+                        if (length > MAX_EMITTED_FOUND_STRING_CHARS) {
+                            if (previewLength <= 3) {
+                                it.take(previewLength)
+                            } else {
+                                it.take(previewLength - 3) + "..."
+                            }
+                        } else {
+                            it
+                        }
+                    }
                     val fs = FoundString(length, offset.toLong(), str)
                     // Log.v(TAG,str);
                     progress(i, bytes.size, fs)
@@ -400,4 +412,4 @@ fun Simpson3_8(f: (Double) -> Double, a: Double, b: Double, N: Int, gamma: Doubl
 
 private fun log2(a: Double): Double {
     return ln(a) / ln(2.0)
-}
+}

app/src/test/java/com/kyhsgeekcode/disassembler/AnalyzerStringSearchTest.kt

@@ -0,0 +1,26 @@
+package com.kyhsgeekcode.disassembler
+
+import org.junit.jupiter.api.Assertions.assertNotNull
+import org.junit.jupiter.api.Assertions.assertTrue
+import org.junit.jupiter.api.Test
+
+@OptIn(ExperimentalUnsignedTypes::class)
+class AnalyzerStringSearchTest {
+    @Test
+    fun `searchStrings clips oversized string matches before emitting them`() {
+        val analyzer = Analyzer(ByteArray(2 * 1024 * 1024) { 'A'.code.toByte() } + byteArrayOf(0))
+        var foundString: FoundString? = null
+
+        analyzer.searchStrings(1, Int.MAX_VALUE) { _, _, result ->
+            if (result != null) {
+                foundString = result
+            }
+        }
+
+        assertNotNull(foundString)
+        assertTrue(
+            foundString!!.string.length <= 4_096,
+            "Analyzer should not allocate oversized string matches before handing them to the UI layer"
+        )
+    }
+}