improve fix for major bug with unflushed stdio

Author: andrew-taylor

dcc_check_output.c

@@ -7,6 +7,7 @@ static int init_check_output(void) {
 }
 
 static void __dcc_check_output(int fd, const char *buf, size_t size) {
+	expected_stdout = (unsigned char *)getenv("DCC_EXPECTED_STDOUT");
 }
 
 static void __dcc_check_close(int fd) {

dcc_dual_sanitizers.c

@@ -138,6 +138,7 @@ struct system_call {
 static int synchronization_terminated;
 
 static void disconnect_sanitizers(void) {
+	debug_printf(2, "disconnect_sanitizers()\n");
 	if (synchronization_terminated) {
 		return;
 	}
@@ -206,8 +207,8 @@ static void stop_sanitizer2(void) {
 
 static void synchronization_failed(void) {
 	debug_printf(1, "warning: sanitizer synchronization lost\n");
-	if (debug_level > 1) {
-		debug_printf(2, "sleeping for 3600 seconds because in debug mode\n");
+	if (debug_level > 3) {
+		debug_printf(3, "sleeping for 3600 seconds because in debug mode\n");
 		sleep(3600);
 	}
 	stop_sanitizer2();
@@ -219,7 +220,7 @@ static void synchronization_failed(void) {
 static void synchronize_system_call(enum which_system_call which, int64_t n) {
 	debug_printf(3, "synchronize_system_call(%s, %d)\n", system_call_names[which], (int)n);
 	if (synchronization_terminated) {
-		debug_printf(2, "synchronization_terminated\n");
+		debug_printf(2, "synchronize_system_calls - synchronization_terminated\n");
 #if __I_AM_SANITIZER2__
 		__dcc_error_exit();
 #endif
@@ -261,7 +262,7 @@ static int64_t synchronize_system_call_result(enum which_system_call which
 	, int64_t return_value) {
 	debug_printf(3, "synchronize_system_call_result(%s, %d)\n", system_call_names[which], (int)return_value);
 	if (synchronization_terminated) {
-		debug_printf(2, "synchronization_terminated\n");
+		debug_printf(2, "synchronize_system_call_result - synchronization_terminated\n");
 #if __I_AM_SANITIZER2__
 		__dcc_error_exit();
 #endif

explain_output_difference.py

@@ -122,11 +122,10 @@ def explain_output_difference1(loc, output_stream, color):
 
 	print("of an", danger('incorrect output line.'), file=output_stream)
 	print('Byte', actual_column + 1, 'of line', line_number, "of program output was incorrect.", file=output_stream)
-
 	if not actual_line[actual_column+1:]:
 		if actual_line.rstrip(b'\n') + expected_byte == expected_line.rstrip(b'\n'):
 			print("A", "'" + danger(sanitize(expected_byte)) + "'", "was missing from the end of the output line.", file=output_stream)
-		else:
+		elif actual_column > 1:
 			print("The characters you printed were correct, but more characters were expected.", file=output_stream)
 
 	print("The correct output line was:", file=output_stream)

tests/check_output/simple_check_output.sh

@@ -43,6 +43,8 @@ function run_test {
 run_test default-1                        ""                                                $'Hello!\n'
 
 run_test no-output-1-fail                 ""                                                $''
+run_test one-byte-missing-fail            ""                                                $'Hello\n'
+run_test two-bytes-missing-fail            ""                                               $'Hell\n'
 
 run_test trailing-white-space-1           ""                                                $'Hello!   \n'
 run_test trailing-white-space-2-fail      "DCC_IGNORE_TRAILING_WHITE_SPACE=0"               $'Hello!   \n'

tests/expected_output/default/simple_check_output.txt

@@ -15,13 +15,61 @@ Execution failed because program produced no output.
 The first expected line was:
 Hello!
 
-*** Test 3 - trailing-white-space-1
+*** Test 3 - one-byte-missing-fail
+*** Test Environment 
+expected output: Hello!
+
+actual output  : Hello
+
+
+Execution stopped because of an incorrect output line.
+Byte 6 of line 1 of program output was incorrect.
+A '!' was missing from the end of the output line.
+The correct output line was:
+Hello!
+Your program printed this line:
+Hello
+
+Execution stopped in main(argc=2, argv=0x<deleted-hexadecimal-constant>) in tmp.c at line 2:
+
+#include <stdio.h>
+-->int main(int argc, char *argv[]) {printf("%s", argv[1]);return 0;}
+
+Values when execution stopped:
+
+argc =  <deleted-value>
+argv[1] =  <deleted-value>
+*** Test 4 - two-bytes-missing-fail
+*** Test Environment 
+expected output: Hello!
+
+actual output  : Hell
+
+
+Execution stopped because of an incorrect output line.
+Byte 5 of line 1 of program output was incorrect.
+The characters you printed were correct, but more characters were expected.
+The correct output line was:
+Hello!
+Your program printed this line:
+Hell
+
+Execution stopped in main(argc=2, argv=0x<deleted-hexadecimal-constant>) in tmp.c at line 2:
+
+#include <stdio.h>
+-->int main(int argc, char *argv[]) {printf("%s", argv[1]);return 0;}
+
+Values when execution stopped:
+
+argc =  <deleted-value>
+argv[1] =  <deleted-value>
+*** Test 5 - trailing-white-space-1
 *** Test Environment 
 expected output: Hello!
 
 actual output  : Hello!   
 
-*** Test 4 - trailing-white-space-2-fail
+*** Test 6 - trailing-white-space-2-fail
 *** Test Environment DCC_IGNORE_TRAILING_WHITE_SPACE=0
 expected output: Hello!
 
@@ -44,7 +92,7 @@ Values when execution stopped:
 
 argc =  <deleted-value>
 argv[1] =  <deleted-value>
-*** Test 5 - extra-new-line-1-fail
+*** Test 7 - extra-new-line-1-fail
 *** Test Environment 
 expected output: Hello!
 
@@ -65,14 +113,14 @@ Values when execution stopped:
 
 argc =  <deleted-value>
 argv[1] =  <deleted-value>
-*** Test 6 - extra-new-line-2
+*** Test 8 - extra-new-line-2
 *** Test Environment DCC_IGNORE_EMPTY_LINES=1
 expected output: Hello!
 
 actual output  : Hello!
 
 
-*** Test 7 - missing-new-line-1-fail
+*** Test 9 - missing-new-line-1-fail
 *** Test Environment 
 expected output: Hello!
 
@@ -83,7 +131,7 @@ Your program produced all the expected output, except the last newline ('\n') wa
 
 For more information go to https://comp1511unsw.github.io/dcc/missing_newline.html
 
-*** Test 8 - ignore-case-1-fail
+*** Test 10 - ignore-case-1-fail
 *** Test Environment 
 expected output: Hello!
 
@@ -106,13 +154,13 @@ Values when execution stopped:
 
 argc =  <deleted-value>
 argv[1] =  <deleted-value>
-*** Test 9 - ignore-case-2
+*** Test 11 - ignore-case-2
 *** Test Environment DCC_IGNORE_CASE=1
 expected output: Hello!
 
 actual output  : hEllo!
 
-*** Test 10 - ignore-white-space-1-fail
+*** Test 12 - ignore-white-space-1-fail
 *** Test Environment 
 expected output: Hello!
 
@@ -135,19 +183,19 @@ Values when execution stopped:
 
 argc =  <deleted-value>
 argv[1] =  <deleted-value>
-*** Test 11 - ignore-white-space-2
+*** Test 13 - ignore-white-space-2
 *** Test Environment DCC_IGNORE_WHITE_SPACE=1
 expected output: Hello!
 
 actual output  : H ello	!
 
-*** Test 12 - ignore-characters-1
+*** Test 14 - ignore-characters-1
 *** Test Environment DCC_IGNORE_CHARACTERS=+
 expected output: Hello!
 
 actual output  : +++Hello!+++
 
-*** Test 13 - ignore-characters-2-fail
+*** Test 15 - ignore-characters-2-fail
 *** Test Environment DCC_IGNORE_CHARACTERS=lzn
 expected output: Hello!
 
@@ -171,13 +219,13 @@ Values when execution stopped:
 
 argc =  <deleted-value>
 argv[1] =  <deleted-value>
-*** Test 14 - ignore-characters-3
+*** Test 16 - ignore-characters-3
 *** Test Environment DCC_IGNORE_CHARACTERS=lzno!
 expected output: Hello!
 
 actual output  : Hen
 
-*** Test 15 - compare-only-characters-1-fail
+*** Test 17 - compare-only-characters-1-fail
 *** Test Environment DCC_COMPARE_ONLY_CHARACTERS=Hel
 expected output: Hello!
 
@@ -200,13 +248,13 @@ Values when execution stopped:
 
 argc =  <deleted-value>
 argv[1] =  <deleted-value>
-*** Test 16 - compare-only-characters-2
+*** Test 18 - compare-only-characters-2
 *** Test Environment DCC_COMPARE_ONLY_CHARACTERS=el
 expected output: Hello!
 
 actual output  : HiheHilloHi	!
 
-*** Test 17 - compare-only-characters-3-fail
+*** Test 19 - compare-only-characters-3-fail
 *** Test Environment DCC_COMPARE_ONLY_CHARACTERS=hel
 expected output: Hello!
 
@@ -229,7 +277,7 @@ Values when execution stopped:
 
 argc =  <deleted-value>
 argv[1] =  <deleted-value>
-*** Test 18 - compare-only-characters-4
+*** Test 20 - compare-only-characters-4
 *** Test Environment DCC_IGNORE_CASE=1 DCC_COMPARE_ONLY_CHARACTERS=hel
 expected output: Hello!