[igt-dev] [PATCH i-g-t] lib/igt_core: add helper for srandom seed initialization

[Kamil Konieczny <kamil.konieczny@linux.intel.com>]

From: Łukasz Łaguna <lukasz.laguna@intel.com>

It allows to set specific value with IGT_SRANDOM environment variable.

Cc: Marcin Bernatowicz <marcin.bernatowicz@linux.intel.com>
Signed-off-by: Łukasz Łaguna <lukasz.laguna@intel.com>
Signed-off-by: Kamil Konieczny <kamil.konieczny@linux.intel.com>
---
 lib/igt_core.c | 16 ++++++++++++++++
 lib/igt_core.h |  2 ++
 2 files changed, 18 insertions(+)

diff --git a/lib/igt_core.c b/lib/igt_core.c
index eff3d4272..cd9c2002d 100644
--- a/lib/igt_core.c
+++ b/lib/igt_core.c
@@ -3367,6 +3367,22 @@ err:
 	return -1;
 }
 
+/**
+ * igt_srandom:
+ *
+ * It initializes seed for random number generator.
+ * If specific value is needed it can be set with IGT_SRANDOM environment
+ * variable.
+ */
+void igt_srandom(void)
+{
+	const char *param = getenv("IGT_SRANDOM");
+	int seed = param ? atoi(param) : time(NULL);
+
+	srandom(seed);
+	igt_info("Using IGT_SRANDOM=%d for randomisation\n", seed);
+}
+
 /* IGT wrappers around libpciaccess init/cleanup functions */
 
 static void pci_system_exit_handler(int sig)
diff --git a/lib/igt_core.h b/lib/igt_core.h
index 5d5593e05..ef6bed6a5 100644
--- a/lib/igt_core.h
+++ b/lib/igt_core.h
@@ -1448,6 +1448,8 @@ int igt_system_quiet(const char *command);
 		free(buf); \
 	} while (0)
 
+void igt_srandom(void);
+
 /**
  * igt_trace:
  * @format: printf-style format string with optional args
-- 
2.39.2