v4.19.13 snapshot.
diff --git a/tools/perf/util/path.c b/tools/perf/util/path.c
new file mode 100644
index 0000000..ca56ba2
--- /dev/null
+++ b/tools/perf/util/path.c
@@ -0,0 +1,93 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * I'm tired of doing "vsnprintf()" etc just to open a
+ * file, so here's a "return static buffer with printf"
+ * interface for paths.
+ *
+ * It's obviously not thread-safe. Sue me. But it's quite
+ * useful for doing things like
+ *
+ * f = open(mkpath("%s/%s.perf", base, name), O_RDONLY);
+ *
+ * which is what it's designed for.
+ */
+#include "cache.h"
+#include "path.h"
+#include <linux/kernel.h>
+#include <limits.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <dirent.h>
+#include <unistd.h>
+
+static char bad_path[] = "/bad-path/";
+/*
+ * One hack:
+ */
+static char *get_pathname(void)
+{
+ static char pathname_array[4][PATH_MAX];
+ static int idx;
+
+ return pathname_array[3 & ++idx];
+}
+
+static char *cleanup_path(char *path)
+{
+ /* Clean it up */
+ if (!memcmp(path, "./", 2)) {
+ path += 2;
+ while (*path == '/')
+ path++;
+ }
+ return path;
+}
+
+char *mkpath(const char *fmt, ...)
+{
+ va_list args;
+ unsigned len;
+ char *pathname = get_pathname();
+
+ va_start(args, fmt);
+ len = vsnprintf(pathname, PATH_MAX, fmt, args);
+ va_end(args);
+ if (len >= PATH_MAX)
+ return bad_path;
+ return cleanup_path(pathname);
+}
+
+int path__join(char *bf, size_t size, const char *path1, const char *path2)
+{
+ return scnprintf(bf, size, "%s%s%s", path1, path1[0] ? "/" : "", path2);
+}
+
+int path__join3(char *bf, size_t size, const char *path1, const char *path2, const char *path3)
+{
+ return scnprintf(bf, size, "%s%s%s%s%s", path1, path1[0] ? "/" : "",
+ path2, path2[0] ? "/" : "", path3);
+}
+
+bool is_regular_file(const char *file)
+{
+ struct stat st;
+
+ if (stat(file, &st))
+ return false;
+
+ return S_ISREG(st.st_mode);
+}
+
+/* Helper function for filesystems that return a dent->d_type DT_UNKNOWN */
+bool is_directory(const char *base_path, const struct dirent *dent)
+{
+ char path[PATH_MAX];
+ struct stat st;
+
+ sprintf(path, "%s/%s", base_path, dent->d_name);
+ if (stat(path, &st))
+ return false;
+
+ return S_ISDIR(st.st_mode);
+}