[PATCH v8 2/4] perf test: Support external tests for separate objdir

[Andi Kleen <ak@linux.intel.com>]

Extend the searching for the test files so that it works
when running perf from a separate objdir, and also when
the perf executable is symlinked.

Signed-off-by: Andi Kleen <ak@linux.intel.com>

----

v2: Fix string test (Namhyung)
Handle both in source and out of source builds.
v3: Remove duplicated string check (Namhyung)
---
 tools/perf/tests/tests-scripts.c | 35 +++++++++++++++++++++++++++++---
 1 file changed, 32 insertions(+), 3 deletions(-)

diff --git a/tools/perf/tests/tests-scripts.c b/tools/perf/tests/tests-scripts.c
index e2042b368269..8dc1e398288c 100644
--- a/tools/perf/tests/tests-scripts.c
+++ b/tools/perf/tests/tests-scripts.c
@@ -29,16 +29,45 @@
 
 static int shell_tests__dir_fd(void)
 {
-	char path[PATH_MAX], *exec_path;
-	static const char * const devel_dirs[] = { "./tools/perf/tests/shell", "./tests/shell", };
+	struct stat st;
+	char path[PATH_MAX], path2[PATH_MAX], *exec_path;
+	static const char * const devel_dirs[] = {
+		"./tools/perf/tests/shell",
+		"./tests/shell",
+		"./source/tests/shell"
+	};
+	int fd;
+	char *p;
 
 	for (size_t i = 0; i < ARRAY_SIZE(devel_dirs); ++i) {
-		int fd = open(devel_dirs[i], O_PATH);
+		fd = open(devel_dirs[i], O_PATH);
 
 		if (fd >= 0)
 			return fd;
 	}
 
+	/* Use directory of executable */
+	if (readlink("/proc/self/exe", path2, sizeof path2) < 0)
+		return -1;
+	/* Follow another level of symlink if there */
+	if (lstat(path2, &st) == 0 && (st.st_mode & S_IFMT) == S_IFLNK) {
+		scnprintf(path, sizeof(path), path2);
+		if (readlink(path, path2, sizeof path2) < 0)
+			return -1;
+	}
+	/* Get directory */
+	p = strrchr(path2, '/');
+	if (p)
+		*p = 0;
+	scnprintf(path, sizeof(path), "%s/tests/shell", path2);
+	fd = open(path, O_PATH);
+	if (fd >= 0)
+		return fd;
+	scnprintf(path, sizeof(path), "%s/source/tests/shell", path2);
+	fd = open(path, O_PATH);
+	if (fd >= 0)
+		return fd;
+
 	/* Then installed path. */
 	exec_path = get_argv_exec_path();
 	scnprintf(path, sizeof(path), "%s/tests/shell", exec_path);
-- 
2.45.2