The changes reflect the feature request eclipse-openj9#16416 - part 2…

… of eclipse-openj9#20641

Adding cmdline option to specify string length to be printed.
-Xtrace:methodstrarglen=[1-128]
methodStrArgLen takes an unsigned integer value from 1 to 128
If no methodStrArgLen is specified, or is set to 0, the printed length is the default value of 32.
Other invalid inputs result in the following:
"Error processing trace option, detail: methodstrarglen takes an unsigned integer value from 0 to 128
 Trace option unrecognized: -Xtrace:methodStrArgLen
 Error processing trace option: -Xtrace:methodStrArgLen=<invalid input>
"

There will be subsequent PRs for tests (part 3).

Closes: eclipse-openj9#16416
Signed-off-by: Nick Kamal <[email protected]>

runtime/oti/j9trace.h

@@ -63,6 +63,7 @@ typedef struct RasGlobalStorage {
 	void *  traceMethodTable;
 	int     stackdepth;
 	unsigned int    stackCompressionLevel;
+	unsigned int    methodStrArgLength;
 	ConfigureTraceFunction configureTraceEngine;
 #if defined(J9VM_OPT_CRIU_SUPPORT)
 	CRIURestoreInitializeTrace criuRestoreInitializeTrace;

runtime/rastrace/j9rastrace.h

@@ -54,6 +54,7 @@ extern "C" {
 #define RAS_STACKDEPTH_KEYWORD          "STACKDEPTH"
 #define RAS_SLEEPTIME_KEYWORD           "SLEEPTIME"
 #define RAS_COMPRESSION_LEVEL_KEYWORD   "STACKCOMPRESSIONLEVEL"
+#define RAS_METHOD_STRING_LENGTH_KEYWORD   "METHODSTRARGLEN"
 
 /*
  * ======================================================================
@@ -130,6 +131,7 @@ omr_error_t processTriggerMethodClause(OMR_VMThread *, char *, BOOLEAN atRuntime
 void doTriggerActionJstacktrace(OMR_VMThread *thr);
 omr_error_t setStackDepth(J9JavaVM *thr, const char * value, BOOLEAN atRuntime);
 omr_error_t setStackCompressionLevel(J9JavaVM * vm, const char *str, BOOLEAN atRuntime);
+omr_error_t setMethodStrArgLength(J9JavaVM * vm, const char *str, BOOLEAN atRuntime);
 
 /*
  * =============================================================================

runtime/rastrace/method_trace.c

@@ -481,6 +481,8 @@ traceMethodArgObject(J9VMThread *thr, UDATA* arg0EA, char* cursor, UDATA length)
 		J9ROMClass * romClass = clazz->romClass;
 		J9UTF8* className = J9ROMCLASS_CLASSNAME(romClass);
 		J9JavaVM *vm = thr->javaVM;
+		const unsigned int methodStrArgLength = ((RasGlobalStorage *)thr->javaVM->j9rasGlobalStorage)->methodStrArgLength;
+		unsigned int strArgLength = methodStrArgLength == 0 ? DEFAULT_STRING_LENGTH : methodStrArgLength;
 
 		if (clazz == J9VMJAVALANGSTRING_OR_NULL(vm)) {
 			/* string arg */
@@ -490,7 +492,7 @@ traceMethodArgObject(J9VMThread *thr, UDATA* arg0EA, char* cursor, UDATA length)
 			char *stringArgUTF8 = vmFuncs->copyStringToUTF8WithMemAlloc(thr, object, J9_STR_NULL_TERMINATE_RESULT, "  ", 2, stringArgBuffer, DEFAULT_BUFFER_LENGTH, NULL);
 
 			if(DEFAULT_STRING_LENGTH < strlen(stringArgUTF8)) {
-				j9str_printf(PORTLIB, cursor, length, "(String)%.*s...", (U_32)DEFAULT_STRING_LENGTH, J9UTF8_DATA(stringArgUTF8));
+				j9str_printf(PORTLIB, cursor, length, "(String)%.*s...", (U_32)strArgLength, J9UTF8_DATA(stringArgUTF8));
 			} else {
 				j9str_printf(PORTLIB, cursor, length, "(String)%.*s", (U_32)J9UTF8_LENGTH(stringArgUTF8), J9UTF8_DATA(stringArgUTF8));
 			}

runtime/rastrace/method_trigger.c

@@ -59,7 +59,7 @@ static const StackTraceFormattingFunction stackTraceFormattingFunctions[] = {
 };
 
 #define NUM_STACK_TRACE_FORMATTING_FUNCTIONS (sizeof(stackTraceFormattingFunctions) / sizeof(stackTraceFormattingFunctions[0]))
-
+#define MAX_STRING_LENGTH 128
 
 /**************************************************************************
  * name        - rasSetTriggerTrace
@@ -547,6 +547,48 @@ decimalString2Int(J9PortLibrary* portLibrary, const char *decString, I_32 signed
 	return num;
 }
 
+/**************************************************************************
+ * name        - setMethodStrArgLength
+ * description - Set method string argument length
+ * parameters  - thr, trace options, atRuntime flag
+ * returns     - JNI return code
+ *************************************************************************/
+omr_error_t
+setMethodStrArgLength(J9JavaVM *vm, const char *str, BOOLEAN atRuntime)
+{
+	PORT_ACCESS_FROM_JAVAVM(vm);
+	int value, length;
+	omr_error_t rc = OMR_ERROR_NONE;
+	const char *p;
+
+	if (getParmNumber(str) != 1) {
+		goto err;
+	}
+
+	p = getPositionalParm(1, str, &length);
+
+	if (length > 3) {
+		goto err;
+	}
+
+	value = decimalString2Int(PORTLIB, p, FALSE, &rc);
+	if (OMR_ERROR_NONE != rc) {
+		goto err;
+	}
+
+	if ((0 > value) ||
+			(MAX_STRING_LENGTH < value)) {
+		goto err;
+	}
+
+	RAS_GLOBAL_FROM_JAVAVM(methodStrArgLength,vm) = (unsigned int)value;
+	return OMR_ERROR_NONE;
+
+err:
+	vaReportJ9VMCommandLineError(PORTLIB, takes an unsigned integer value from 1 to %d", MAX_STRING_LENGTH);
+	return OMR_ERROR_INTERNAL;
+}
+
 /**************************************************************************
  * name        - addTriggeredMethodSpec
  * description - Take a user specified method trigger rule (from the
@@ -654,12 +696,12 @@ addTriggeredMethodSpec(J9VMThread *thr, const char *ptrMethodSpec, const struct
 		}
 
 		if (methodRule->entryAction != NULL && methodRule->entryAction->name != NULL
-		    && j9_cmdla_stricmp((char *)methodRule->entryAction->name, "jstacktrace") == 0) {
+			&& j9_cmdla_stricmp((char *)methodRule->entryAction->name, "jstacktrace") == 0) {
 			/* set up the current method spec to be enabled for trace */
 			setMethod(thr->javaVM, ptrMethodSpec, FALSE);
 		}
 		if (methodRule->exitAction != NULL && methodRule->exitAction->name != NULL
-		    && j9_cmdla_stricmp((char *)methodRule->exitAction->name, "jstacktrace") == 0) {
+			&& j9_cmdla_stricmp((char *)methodRule->exitAction->name, "jstacktrace") == 0) {
 			/* set up the current method spec to be enabled for trace */
 			setMethod(thr->javaVM, ptrMethodSpec, FALSE);
 		}

runtime/rastrace/trcengine.c

@@ -117,6 +117,7 @@ const struct traceOption TRACE_OPTIONS[] =
 	{RAS_METHODS_KEYWORD, FALSE, setMethod},
 	{RAS_STACKDEPTH_KEYWORD, TRUE, setStackDepth},
 	{RAS_COMPRESSION_LEVEL_KEYWORD, TRUE, setStackCompressionLevel},
+	{RAS_METHOD_STRING_LENGTH_KEYWORD, FALSE, setMethodStrArgLength},
 };
 
 #define NUMBER_OF_TRACE_OPTIONS ( sizeof(TRACE_OPTIONS) / sizeof(struct traceOption))