Allow error checking functions to take format and arguments

src-disl-agent/common.c

@@ -2,6 +2,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdarg.h>
 #include <string.h>
 #include <strings.h>
 #include <assert.h>
@@ -31,8 +32,11 @@ find_value_index (const char * strval, const char * values [], int nvals) {
  * an error code indicating a generic error.
  */
 void
-die_with_error (const char * message) {
-	fprintf (stderr, "%s%s\n", ERROR_PREFIX, message);
+die_with_error (const char * restrict format, va_list args) {
+	fprintf (stderr, AGENT_NAME ": error: ");
+	vfprintf (stderr, format, args);
+	fprintf (stderr, "\n");
+
 	exit (ERROR_GENERIC);
 }
 
@@ -44,15 +48,22 @@ die_with_error (const char * message) {
  * exits with an error code indicating failure in standard library call.
  */
 void
-die_with_std_error (const char * message, int errnum) {
+die_with_std_error (int errnum, const char * restrict format, va_list args) {
 	char * cause = strerror (errnum);
-	fprintf (stderr, "%s%s\ncause: %s\n", ERROR_PREFIX, message, cause);
+	fprintf (stderr, AGENT_NAME ": std-error: %s\n", cause);
+
+	fprintf (stderr, AGENT_NAME ": ");
+	vfprintf (stderr, format, args);
+	fprintf (stderr, "\n");
+
 	exit (ERROR_STD);
 }
 
+
 // ****************************************************************************
 // STRING UTILS SECTION
 // ****************************************************************************
+
 size_t
 substr_count(const char * string, const char * restrict substr) {
 	size_t count = 0;
@@ -117,13 +128,17 @@ __get_error_message (const DWORD msg_id) {
  * exits with an error code indicating failure in standard library call.
  */
 void
-die_with_win_error (const char * message, DWORD errnum) {
-	char * cause = __get_error_message (errnum);
-	fprintf (stderr, "%s%s\ncause: %s", ERROR_PREFIX, message, cause);
+die_with_win_error (DWORD errnum, const char * restrict format, va_list args) {
+	const char * restrict cause = __get_error_message (errnum);
+	fprintf (stderr, AGENT_NAME ": std-error: %s\n", cause);
 	if (cause != NULL) {
 		free (cause);
 	}
 
+	fprintf (stderr, AGENT_NAME ": ");
+	vfprintf (stderr, format, args);
+	fprintf (stderr, "\n");
+
 	exit (ERROR_STD);
 }
 

src-disl-agent/common.h

@@ -4,9 +4,9 @@
 #define _POSIX_C_SOURCE 200809L
 
 #include <stdio.h>
+#include <stdarg.h>
 #include <stdbool.h>
 #include <errno.h>
-#include <sys/types.h>
 
 #define __STDC_FORMAT_MACROS
 #include <inttypes.h>
@@ -45,6 +45,7 @@
 
 
 /**
+ * Prints a warning message to stderr.
  *
  * @format	format string for printf
  * @args	arguments associated with the format string
@@ -66,12 +67,12 @@ int find_value_index (const char * strval, const char * values [], int nvals);
 #define ERROR_STD 10002
 #define ERROR_JVMTI 10003
 
-#define ERROR_PREFIX "disl-agent: error: "
+#define AGENT_NAME "disl-agent"
 
 //
 
-void die_with_error (const char * message);
-void die_with_std_error (const char * message, int errnum);
+void die_with_error (const char * format, va_list args);
+void die_with_std_error (int errnum, const char * format, va_list args);
 
 // ****************************************************************************
 // STRING UTILS SECTION
@@ -103,9 +104,14 @@ split_string(char * string, const char * restrict separator, size_t * tokens);
  * error condition is true.
  */
 static inline void
-check_error (bool error, const char * message) {
+check_error (bool error, const char * format, ...) {
 	if (error) {
-		die_with_error (message);
+		va_list args;
+		va_start (args, format);
+
+		die_with_error (format, args);
+
+		va_end (args);
 	}
 }
 
@@ -115,9 +121,14 @@ check_error (bool error, const char * message) {
  * error condition is true.
  */
 static inline void
-check_std_error (bool error, const char * message) {
+check_std_error (bool error, const char * format, ...) {
 	if (error) {
-		die_with_std_error (message, errno);
+		va_list args;
+		va_start (args, format);
+
+		die_with_std_error (errno, format, args);
+
+		va_end (args);
 	}
 }
 
@@ -137,7 +148,7 @@ warn_std_error (bool error, const char * message) {
 
 #ifdef MINGW
 
-void die_with_win_error (const char * message, DWORD errnum);
+void die_with_win_error (DWORD errnum, const char * message, va_list args);
 
 
 /**
@@ -145,13 +156,17 @@ void die_with_win_error (const char * message, DWORD errnum);
  * error condition is true.
  */
 static inline void
-check_win_error (bool error, const char * message) {
+check_win_error (bool error, const char * format, ...) {
 	if (error) {
-		die_with_win_error (message, GetLastError ());
+		va_list args;
+		va_start (args, format);
+
+		die_with_win_error (GetLastError (), format, args);
+
+		va_end (args);
 	}
 }
 
 #endif /* MINGW */
 
-
 #endif /* _COMMON_H_ */

src-disl-agent/dislagent.c

@@ -210,8 +210,8 @@ __instrument_class (
 	//
 	if (response->result == INSTRUMENT_CLASS_RESPONSE__INSTRUMENT_CLASS_RESULT__ERROR) {
 		fprintf (
-			stderr, "%sinstrumentation server error:\n%s\n",
-			ERROR_PREFIX, response->errormessage
+			stderr, AGENT_NAME ": instrumentation server error:\n%s\n",
+			response->errormessage
 		);
 
 		exit (ERROR_SERVER);
@@ -709,11 +709,11 @@ __get_jvmti (JavaVM * jvm) {
 		// JVMTI interface. This is a fatal error for the agent.
 		//
 		fprintf (
-			stderr,
-			"%sFailed to obtain JVMTI interface Version 1 (0x%x)\n"
+			stderr, AGENT_NAME "error: "
+			"Failed to obtain JVMTI interface Version 1 (0x%x)\n"
 			"JVM GetEnv() returned %ld - is your Java runtime "
 			"version 1.5 or newer?\n",
-			ERROR_PREFIX, JVMTI_VERSION_1, (long) result
+			JVMTI_VERSION_1, (long) result
 		);
 
 		exit (ERROR_JVMTI);

src-disl-agent/jvmtiutil.c

@@ -10,8 +10,8 @@
 
 //
 
-#ifndef ERROR_PREFIX
-#error ERROR_PREFIX macro has to be defined
+#ifndef AGENT_NAME
+#error AGENT_NAME macro has to be defined
 #endif
 
 #ifndef ERROR_JVMTI
@@ -175,16 +175,25 @@ jvmti_get_system_property_string (
  * interface.
  */
 void
-die_with_jvmti_error (jvmtiEnv *jvmti, jvmtiError errnum, const char *str) {
-	char * errnum_str = NULL;
-	(void) (*jvmti)->GetErrorName (jvmti, errnum, &errnum_str);
+die_with_jvmti_error (
+	jvmtiEnv * jvmti, jvmtiError error,
+	const char * restrict format, va_list args
+) {
+	// JVMTI error
+	char * cause = NULL;
+	(void) (*jvmti)->GetErrorName (jvmti, error, &cause);
 
 	fprintf (
-		stderr, "%sJVMTI: %d (%s): %s\n",
-		ERROR_PREFIX, errnum,
-		(errnum_str == NULL ? "Unknown" : errnum_str),
-		(str == NULL ? "" : str)
+		stderr, AGENT_NAME ": jvmti-error: %s (%d)\n",
+		(cause != NULL) ? cause : "unknown", error
 	);
 
+	(*jvmti)->Deallocate (jvmti, (unsigned char *) cause);
+
+	// agent error
+	fprintf (stderr, AGENT_NAME ": ");
+	vfprintf (stderr, format, args);
+	fprintf (stderr, "\n");
+
 	exit (ERROR_JVMTI);
 }

src-disl-agent/jvmtiutil.h

@@ -3,12 +3,14 @@
 
 #include "common.h"
 
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdlib.h>
+
 #include <jvmti.h>
 
 //
 
-void die_with_jvmti_error (jvmtiEnv * jvmti, jvmtiError error, const char * message);
-
 unsigned char * jvmti_alloc_copy (jvmtiEnv * jvmti, const void * src, size_t size);
 
 bool jvmti_redefine_class (
@@ -24,6 +26,12 @@ char * jvmti_get_system_property_string (
 	jvmtiEnv * jvmti, const char * name, const char * dflval
 );
 
+//
+
+void die_with_jvmti_error (
+	jvmtiEnv * jvmti, jvmtiError error, const char * format, va_list args
+);
+
 
 /**
  * Checks whether a JVMTI invocation returned an error. Every JVMTI interface
@@ -31,9 +39,17 @@ char * jvmti_get_system_property_string (
  * down the line.
  */
 static inline void
-check_jvmti_error(jvmtiEnv *jvmti, jvmtiError errnum, const char * message) {
+check_jvmti_error (
+	jvmtiEnv * restrict jvmti, jvmtiError errnum,
+	const char * restrict format, ...
+) {
 	if (errnum != JVMTI_ERROR_NONE) {
-		die_with_jvmti_error (jvmti, errnum, message);
+		va_list args;
+		va_start (args, format);
+
+		die_with_jvmti_error (jvmti, errnum, format, args);
+
+		va_end (args);
 	}
 }