[Qemu-trivial] [PATCH] tests/boot-sector: Use mkstemp() to create a unique file name

[Thomas Huth <thuth@redhat.com>]

The pxe-test is run for three different targets now (x86_64, i386
and ppc64), and the bios-tables-test is run for two targets (x86_64
and i386). But each of the tests is using an invariant name for the
disk image with the boot sector code - so if the tests are running
in parallel, there is a race condition that they destroy the disk
image of a parallel test program. Let's use mkstemp() to create
unique temporary files here instead.

Reported-by: Sascha Silbe <x-qemu@se-silbe.de>
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 tests/bios-tables-test.c | 2 +-
 tests/boot-sector.c      | 9 +++++++--
 tests/boot-sector.h      | 4 ++--
 tests/pxe-test.c         | 2 +-
 4 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/tests/bios-tables-test.c b/tests/bios-tables-test.c
index 6ea2b6d..812f830 100644
--- a/tests/bios-tables-test.c
+++ b/tests/bios-tables-test.c
@@ -112,7 +112,7 @@ typedef struct {
     g_assert_cmpstr(ACPI_ASSERT_CMP_str, ==, expected); \
 } while (0)
 
-static const char *disk = "tests/acpi-test-disk.raw";
+static char disk[] = "tests/acpi-test-disk-XXXXXX";
 static const char *data_dir = "tests/acpi-test-data";
 #ifdef CONFIG_IASL
 static const char *iasl = stringify(CONFIG_IASL);
diff --git a/tests/boot-sector.c b/tests/boot-sector.c
index e3193c0..e75572f 100644
--- a/tests/boot-sector.c
+++ b/tests/boot-sector.c
@@ -69,10 +69,15 @@ static uint8_t boot_sector[0x7e000] = {
 };
 
 /* Create boot disk file.  */
-int boot_sector_init(const char *fname)
+int boot_sector_init(char *fname)
 {
-    FILE *f = fopen(fname, "w");
+    FILE *f = NULL;
+    int fd;
 
+    fd = mkstemp(fname);
+    if (fd != -1) {
+        f = fdopen(fd, "w");
+    }
     if (!f) {
         fprintf(stderr, "Couldn't open \"%s\": %s", fname, strerror(errno));
         return 1;
diff --git a/tests/boot-sector.h b/tests/boot-sector.h
index f64b477..35d61c7 100644
--- a/tests/boot-sector.h
+++ b/tests/boot-sector.h
@@ -14,8 +14,8 @@
 #ifndef TEST_BOOT_SECTOR_H
 #define TEST_BOOT_SECTOR_H
 
-/* Create boot disk file.  */
-int boot_sector_init(const char *fname);
+/* Create boot disk file. fname must be a suitable string for mkstemp() */
+int boot_sector_init(char *fname);
 
 /* Loop until signature in memory is OK.  */
 void boot_sector_test(void);
diff --git a/tests/pxe-test.c b/tests/pxe-test.c
index 5d3ddbe..34282d3 100644
--- a/tests/pxe-test.c
+++ b/tests/pxe-test.c
@@ -19,7 +19,7 @@
 
 #define NETNAME "net0"
 
-static const char *disk = "tests/pxe-test-disk.raw";
+static char disk[] = "tests/pxe-test-disk-XXXXXX";
 
 static void test_pxe_one(const char *params, bool ipv6)
 {
-- 
1.8.3.1