+/* Helper for functions that need a root filesystem mounted.
+ * NB. Cannot be used for FileIn functions.
+ */
+#define NEED_ROOT(cancel_stmt,fail_stmt) \
+ do { \
+ if (!root_mounted) { \
+ cancel_stmt; \
+ reply_with_error ("%s: you must call 'mount' first to mount the root filesystem", __func__); \
+ fail_stmt; \
+ } \
+ } \
+ while (0)
+
+/* Helper for functions that need an argument ("path") that is absolute.
+ * NB. Cannot be used for FileIn functions.
+ */
+#define ABS_PATH(path,cancel_stmt,fail_stmt) \
+ do { \
+ if ((path)[0] != '/') { \
+ cancel_stmt; \
+ reply_with_error ("%s: path must start with a / character", __func__); \
+ fail_stmt; \
+ } \
+ } while (0)
+
+/* All functions that need an argument that is a device or partition name
+ * must call this macro. It checks that the device exists and does
+ * device name translation (described in the guestfs(3) manpage).
+ * Note that the "path" argument may be modified.
+ *
+ * NB. Cannot be used for FileIn functions.
+ */
+#define RESOLVE_DEVICE(path,cancel_stmt,fail_stmt) \
+ do { \
+ if (STRNEQLEN ((path), "/dev/", 5)) { \
+ cancel_stmt; \
+ reply_with_error ("%s: %s: expecting a device name", __func__, (path)); \
+ fail_stmt; \
+ } \
+ if (device_name_translation ((path)) == -1) { \
+ int err = errno; \
+ cancel_stmt; \
+ errno = err; \
+ reply_with_perror ("%s: %s", __func__, path); \
+ fail_stmt; \
+ } \
+ } while (0)
+
+/* Helper for functions which need either an absolute path in the
+ * mounted filesystem, OR a /dev/ device which exists.
+ *
+ * NB. Cannot be used for FileIn functions.
+ *
+ * NB #2: Functions which mix filenames and device paths should be
+ * avoided, and existing functions should be deprecated. This is
+ * because we intend in future to make device parameters a distinct
+ * type from filenames.
+ */
+#define REQUIRE_ROOT_OR_RESOLVE_DEVICE(path,cancel_stmt,fail_stmt) \
+ do { \
+ if (STREQLEN ((path), "/dev/", 5)) \
+ RESOLVE_DEVICE ((path), cancel_stmt, fail_stmt); \
+ else { \
+ NEED_ROOT (cancel_stmt, fail_stmt); \
+ ABS_PATH ((path), cancel_stmt, fail_stmt); \
+ } \
+ } while (0)
+
+/* NB:
+ * (1) You must match CHROOT_IN and CHROOT_OUT even along error paths.
+ * (2) You must not change directory! cwd must always be "/", otherwise
+ * we can't escape our own chroot.
+ * (3) All paths specified must be absolute.
+ * (4) Neither macro affects errno.
+ */
+#define CHROOT_IN \
+ do { \
+ int __old_errno = errno; \
+ if (chroot (sysroot) == -1) \
+ perror ("CHROOT_IN: sysroot"); \
+ errno = __old_errno; \
+ } while (0)
+#define CHROOT_OUT \
+ do { \
+ int __old_errno = errno; \
+ if (chroot (".") == -1) \
+ perror ("CHROOT_OUT: ."); \
+ errno = __old_errno; \
+ } while (0)
+
+/* Marks functions which are not implemented.
+ * NB. Cannot be used for FileIn functions.
+ */
+#define XXX_NOT_IMPL(errcode) \
+ do { \
+ reply_with_error ("%s: function not implemented", __func__); \
+ return (errcode); \
+ } \
+ while (0)
+
+/* Marks functions which are not available.
+ * NB. Cannot be used for FileIn functions.
+ */
+#define NOT_AVAILABLE(errcode) \
+ do { \
+ reply_with_error ("%s: function not available", __func__); \
+ return (errcode); \
+ } \
+ while (0)
+
+#ifndef __attribute__
+# if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 8)
+# define __attribute__(x) /* empty */
+# endif
+#endif
+
+#ifndef ATTRIBUTE_UNUSED
+# define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
+#endif
+
+#define STREQ(a,b) (strcmp((a),(b)) == 0)
+#define STRCASEEQ(a,b) (strcasecmp((a),(b)) == 0)
+#define STRNEQ(a,b) (strcmp((a),(b)) != 0)
+#define STRCASENEQ(a,b) (strcasecmp((a),(b)) != 0)
+#define STREQLEN(a,b,n) (strncmp((a),(b),(n)) == 0)
+#define STRCASEEQLEN(a,b,n) (strncasecmp((a),(b),(n)) == 0)
+#define STRNEQLEN(a,b,n) (strncmp((a),(b),(n)) != 0)
+#define STRCASENEQLEN(a,b,n) (strncasecmp((a),(b),(n)) != 0)
+#define STRPREFIX(a,b) (strncmp((a),(b),strlen((b))) == 0)
+