Merge pull request #4795 from poettering/dissect

Generalize image dissection logic of nspawn, and make it useful for other tools.

src/basic/fileio.c

@@ -1409,3 +1409,22 @@ int read_nul_string(FILE *f, char **ret) {
 
         return 0;
 }
+
+int mkdtemp_malloc(const char *template, char **ret) {
+        char *p;
+
+        assert(template);
+        assert(ret);
+
+        p = strdup(template);
+        if (!p)
+                return -ENOMEM;
+
+        if (!mkdtemp(p)) {
+                free(p);
+                return -errno;
+        }
+
+        *ret = p;
+        return 0;
+}

src/basic/fileio.h

@@ -88,3 +88,5 @@ int open_tmpfile_linkable(const char *target, int flags, char **ret_path);
 int link_tmpfile(int fd, const char *path, const char *target);
 
 int read_nul_string(FILE *f, char **ret);
+
+int mkdtemp_malloc(const char *template, char **ret);

src/basic/fs-util.h

@@ -84,3 +84,10 @@ enum {
 };
 
 int chase_symlinks(const char *path_with_prefix, const char *root, unsigned flags, char **ret);
+
+/* Useful for usage with _cleanup_(), removes a directory and frees the pointer */
+static inline void rmdir_and_free(char *p) {
+        (void) rmdir(p);
+        free(p);
+}
+DEFINE_TRIVIAL_CLEANUP_FUNC(char*, rmdir_and_free);

src/basic/rm-rf.h

@@ -33,8 +33,6 @@ int rm_rf(const char *path, RemoveFlags flags);
 
 /* Useful for usage with _cleanup_(), destroys a directory and frees the pointer */
 static inline void rm_rf_physical_and_free(char *p) {
-        if (!p)
-                return;
         (void) rm_rf(p, REMOVE_ROOT|REMOVE_PHYSICAL);
         free(p);
 }