tests/tcg: fix unused result warnings

With i386-linux-user target on x86_64 host, this does not introduce any new test
failures.

Signed-off-by: Catalin Patulea <catalinp@google.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>

tests/tcg/test-mmap.c

@@ -429,6 +429,12 @@ void check_file_fixed_mmaps(void)
 	fprintf (stderr, " passed\n");
 }
 
+void checked_write(int fd, const void *buf, size_t count)
+{
+    ssize_t rc = write(fd, buf, count);
+    fail_unless(rc == count);
+}
+
 int main(int argc, char **argv)
 {
 	char tempname[] = "/tmp/.cmmapXXXXXX";
@@ -450,13 +456,15 @@ int main(int argc, char **argv)
 	unlink(tempname);
 
 	/* Fill the file with int's counting from zero and up.  */
-	for (i = 0; i < (pagesize * 4) / sizeof i; i++)
-		write (test_fd, &i, sizeof i);
+    for (i = 0; i < (pagesize * 4) / sizeof i; i++) {
+        checked_write(test_fd, &i, sizeof i);
+    }
+
 	/* Append a few extra writes to make the file end at non 
 	   page boundary.  */
-	write (test_fd, &i, sizeof i); i++;
-	write (test_fd, &i, sizeof i); i++;
-	write (test_fd, &i, sizeof i); i++;
+    checked_write(test_fd, &i, sizeof i); i++;
+    checked_write(test_fd, &i, sizeof i); i++;
+    checked_write(test_fd, &i, sizeof i); i++;
 
 	test_fsize = lseek(test_fd, 0, SEEK_CUR);
 

tests/tcg/testthread.c

@@ -1,3 +1,4 @@
+#include <assert.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
@@ -8,6 +9,12 @@
 #include <sys/wait.h>
 #include <sched.h>
 
+void checked_write(int fd, const void *buf, size_t count)
+{
+    ssize_t rc = write(fd, buf, count);
+    assert(rc == count);
+}
+
 void *thread1_func(void *arg)
 {
     int i;
@@ -15,7 +22,7 @@ void *thread1_func(void *arg)
 
     for(i=0;i<10;i++) {
         snprintf(buf, sizeof(buf), "thread1: %d %s\n", i, (char *)arg);
-        write(1, buf, strlen(buf));
+        checked_write(1, buf, strlen(buf));
         usleep(100 * 1000);
     }
     return NULL;
@@ -27,7 +34,7 @@ void *thread2_func(void *arg)
     char buf[512];
     for(i=0;i<20;i++) {
         snprintf(buf, sizeof(buf), "thread2: %d %s\n", i, (char *)arg);
-        write(1, buf, strlen(buf));
+        checked_write(1, buf, strlen(buf));
         usleep(150 * 1000);
     }
     return NULL;