From 6d059f65bf23f912ec4ebb12022dd3b25b26dd6f Mon Sep 17 00:00:00 2001
From: Herman Chen <herman.chen@rock-chips.com>
Date: Fri, 3 Aug 2018 15:56:03 +0800
Subject: [PATCH] [osal]: Change mpp_env string interface

Set get environment string parameter to const char to avoid modification.

Change-Id: Ib5308407fcac2fa58b194fb8df33380efc1487f9
Signed-off-by: Herman Chen <herman.chen@rock-chips.com>
---
 osal/android/os_env.c    |  2 +-
 osal/inc/mpp_env.h       |  2 +-
 osal/linux/os_env.c      |  2 +-
 osal/mpp_env.cpp         |  2 +-
 osal/os_env.h            |  2 +-
 osal/test/mpp_env_test.c | 13 ++++++-------
 osal/windows/os_env.c    |  2 +-
 7 files changed, 12 insertions(+), 13 deletions(-)

diff --git a/osal/android/os_env.c b/osal/android/os_env.c
index af2bdb13..b06fff6f 100644
--- a/osal/android/os_env.c
+++ b/osal/android/os_env.c
@@ -45,7 +45,7 @@ RK_S32 os_get_env_u32(const char *name, RK_U32 *value, RK_U32 default_value)
     return 0;
 }
 
-RK_S32 os_get_env_str(const char *name, char **value, char *default_value)
+RK_S32 os_get_env_str(const char *name, const char **value, const char *default_value)
 {
     // use unsigned char to avoid warnning
     static unsigned char env_str[2][PROP_VALUE_MAX + 1];
diff --git a/osal/inc/mpp_env.h b/osal/inc/mpp_env.h
index 1fe96108..b2fb7338 100644
--- a/osal/inc/mpp_env.h
+++ b/osal/inc/mpp_env.h
@@ -24,7 +24,7 @@ extern "C" {
 #endif
 
 RK_S32 mpp_env_get_u32(const char *name, RK_U32 *value, RK_U32 default_value);
-RK_S32 mpp_env_get_str(const char *name, char **value, char *default_value);
+RK_S32 mpp_env_get_str(const char *name, const char **value, const char *default_value);
 
 RK_S32 mpp_env_set_u32(const char *name, RK_U32 value);
 RK_S32 mpp_env_set_str(const char *name, char *value);
diff --git a/osal/linux/os_env.c b/osal/linux/os_env.c
index afe10d65..96e68d5c 100644
--- a/osal/linux/os_env.c
+++ b/osal/linux/os_env.c
@@ -40,7 +40,7 @@ RK_S32 os_get_env_u32(const char *name, RK_U32 *value, RK_U32 default_value)
     return 0;
 }
 
-RK_S32 os_get_env_str(const char *name, char **value, char *default_value)
+RK_S32 os_get_env_str(const char *name, const char **value, const char *default_value)
 {
     *value = getenv(name);
     if (NULL == *value) {
diff --git a/osal/mpp_env.cpp b/osal/mpp_env.cpp
index 98d98170..9e4d9d11 100644
--- a/osal/mpp_env.cpp
+++ b/osal/mpp_env.cpp
@@ -24,7 +24,7 @@ RK_S32 mpp_env_get_u32(const char *name, RK_U32 *value, RK_U32 default_value)
     return os_get_env_u32(name, value, default_value);
 }
 
-RK_S32 mpp_env_get_str(const char *name, char **value, char *default_value)
+RK_S32 mpp_env_get_str(const char *name, const char **value, const char *default_value)
 {
     return os_get_env_str(name, value, default_value);
 }
diff --git a/osal/os_env.h b/osal/os_env.h
index 35aeab58..f039c469 100644
--- a/osal/os_env.h
+++ b/osal/os_env.h
@@ -24,7 +24,7 @@ extern "C" {
 #endif
 
 RK_S32 os_get_env_u32(const char *name, RK_U32 *value, RK_U32 default_value);
-RK_S32 os_get_env_str(const char *name, char **value, char *default_value);
+RK_S32 os_get_env_str(const char *name, const char **value, const char *default_value);
 
 RK_S32 os_set_env_u32(const char *name, RK_U32 value);
 RK_S32 os_set_env_str(const char *name, char *value);
diff --git a/osal/test/mpp_env_test.c b/osal/test/mpp_env_test.c
index f3ce2bc1..29721cfd 100644
--- a/osal/test/mpp_env_test.c
+++ b/osal/test/mpp_env_test.c
@@ -25,22 +25,21 @@ char env_test_string[] = "just for debug";
 int main()
 {
     RK_U32 env_debug_u32 = 0x100;
-    char *env_string_str = env_test_string;
+    const char *env_str_out = NULL;
 
     mpp_env_set_u32(env_debug, env_debug_u32);
-    mpp_env_set_str(env_string, env_string_str);
+    mpp_env_set_str(env_string, env_test_string);
     mpp_log("set env: %s to %u\n", env_debug, env_debug_u32);
-    mpp_log("set env: %s to %s\n", env_string, env_string_str);
+    mpp_log("set env: %s to %s\n", env_string, env_test_string);
 
     env_debug_u32 = 0;
-    env_string_str = NULL;
-    mpp_log("clear local value to zero\n");
+    mpp_log("start reading env:\n");
 
     mpp_env_get_u32(env_debug, &env_debug_u32, 0);
-    mpp_env_get_str(env_string, &env_string_str, NULL);
+    mpp_env_get_str(env_string, &env_str_out, NULL);
 
     mpp_log("get env: %s is %u\n", env_debug, env_debug_u32);
-    mpp_log("get env: %s is %s\n", env_string, env_string_str);
+    mpp_log("get env: %s is %s\n", env_string, env_str_out);
 
     return 0;
 }
diff --git a/osal/windows/os_env.c b/osal/windows/os_env.c
index dfd55467..67c919fa 100644
--- a/osal/windows/os_env.c
+++ b/osal/windows/os_env.c
@@ -39,7 +39,7 @@ RK_S32 os_get_env_u32(const char *name, RK_U32 *value, RK_U32 default_value)
     return 0;
 }
 
-RK_S32 os_get_env_str(const char *name, char **value, char *default_value)
+RK_S32 os_get_env_str(const char *name, const char **value, const char *default_value)
 {
     *value = getenv(name);
     if (NULL == *value) {