Merge remote-tracking branch 'remotes/philmd-gitlab/tags/avr-20200721' into staging

AVR patches

Fixes a memory leak reported by Coverity (CID 1430449).

CI jobs result:
. https://gitlab.com/philmd/qemu/-/pipelines/168722631

# gpg: Signature made Tue 21 Jul 2020 19:00:03 BST
# gpg:                using RSA key FAABE75E12917221DCFD6BB2E3E32C2CDEADC0DE
# gpg: Good signature from "Philippe Mathieu-Daudé (F4BUG) <f4bug@amsat.org>" [full]
# Primary key fingerprint: FAAB E75E 1291 7221 DCFD  6BB2 E3E3 2C2C DEAD C0DE

* remotes/philmd-gitlab/tags/avr-20200721:
  hw/avr/boot: Fix memory leak in avr_load_firmware()
  qemu-common: Document qemu_find_file()
  qemu/osdep: Reword qemu_get_exec_dir() documentation
  qemu/osdep: Document os_find_datadir() return value
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

hw/avr/boot.c

@@ -60,7 +60,7 @@ static const char *avr_elf_e_flags_to_cpu_type(uint32_t flags)
 bool avr_load_firmware(AVRCPU *cpu, MachineState *ms,
                        MemoryRegion *program_mr, const char *firmware)
 {
-    const char *filename;
+    g_autofree char *filename = NULL;
     int bytes_loaded;
     uint64_t entry;
     uint32_t e_flags;

include/qemu-common.h

@@ -110,6 +110,23 @@ const char *qemu_get_vm_name(void);
 
 #define QEMU_FILE_TYPE_BIOS   0
 #define QEMU_FILE_TYPE_KEYMAP 1
+/**
+ * qemu_find_file:
+ * @type: QEMU_FILE_TYPE_BIOS (for BIOS, VGA BIOS)
+ *        or QEMU_FILE_TYPE_KEYMAP (for keymaps).
+ * @name: Relative or absolute file name
+ *
+ * If @name exists on disk as an absolute path, or a path relative
+ * to the current directory, then returns @name unchanged.
+ * Otherwise searches for @name file in the data directories, either
+ * configured at build time (DATADIR) or registered with the -L command
+ * line option.
+ *
+ * The caller must use g_free() to free the returned data when it is
+ * no longer required.
+ *
+ * Returns: a path that can access @name, or NULL if no matching file exists.
+ */
 char *qemu_find_file(int type, const char *name);
 
 /* OS specific functions */

include/qemu/osdep.h

@@ -588,7 +588,10 @@ char *qemu_get_local_state_pathname(const char *relative_pathname);
 void qemu_init_exec_dir(const char *argv0);
 
 /* Get the saved exec dir.
- * Caller needs to release the returned string by g_free() */
+ *
+ * The caller is responsible for releasing the value returned with g_free()
+ * after use.
+ */
 char *qemu_get_exec_dir(void);
 
 /**

os-posix.c

@@ -84,6 +84,9 @@ void os_setup_signal_handling(void)
  * Find a likely location for support files using the location of the binary.
  * When running from the build tree this will be "$bindir/../pc-bios".
  * Otherwise, this is CONFIG_QEMU_DATADIR.
+ *
+ * The caller must use g_free() to free the returned data when it is
+ * no longer required.
  */
 char *os_find_datadir(void)
 {

os-win32.c

@@ -57,7 +57,12 @@ void os_setup_early_signal_handling(void)
     atexit(os_undo_timer_resolution);
 }
 
-/* Look for support files in the same directory as the executable.  */
+/*
+ * Look for support files in the same directory as the executable.
+ *
+ * The caller must use g_free() to free the returned data when it is
+ * no longer required.
+ */
 char *os_find_datadir(void)
 {
     return qemu_get_exec_dir();