2 files changed, 14 insertions, 6 deletions
diff --git a/common/env_common.c b/common/env_common.c
index a960aa8..067fe3f 100644
--- a/common/env_common.c
+++ b/common/env_common.c
@@ -81,6 +81,20 @@ const uchar *env_get_addr(int index)
 		return &default_environment[index];
 }
 
+/*
+ * Read an environment variable as a boolean
+ * Return -1 if variable does not exist (default to true)
+ */
+int getenv_yesno(const char *var)
+{
+	char *s = getenv(var);
+
+	if (s == NULL)
+		return -1;
+	return (*s == '1' || *s == 'y' || *s == 'Y' || *s == 't' || *s == 'T') ?
+		1 : 0;
+}
+
 void set_default_env(const char *s)
 {
 	int flags = 0;
diff --git a/common/image.c b/common/image.c
index e93b6e8..69e888c 100644
--- a/common/image.c
+++ b/common/image.c
@@ -416,12 +416,6 @@ static const image_header_t *image_get_ramdisk(ulong rd_addr, uint8_t arch,
 /* Shared dual-format routines */
 /*****************************************************************************/
 #ifndef USE_HOSTCC
-int getenv_yesno(char *var)
-{
-	char *s = getenv(var);
-	return (s && (*s == 'n')) ? 0 : 1;
-}
-
 ulong getenv_bootm_low(void)
 {
 	char *s = getenv("bootm_low");