Add warning when trying to change read-only variable

darcs-hash:20060410153626-ac50b-700ff7687647b8aab47ba79d759d1739cbe60425.gz

3 files changed, 33 insertions, 9 deletions

diff --git a/builtin_set.c b/builtin_set.c
index 5383456e..3588ba7c 100644
--- a/builtin_set.c
+++ b/builtin_set.c
@@ -26,6 +26,18 @@ Functions used for implementing the set builtin.
 #include "parser.h"
 #include "translate.h"
 
+static void my_env_set( wchar_t *key, wchar_t *val, int scope )
+{
+	switch( env_set( key, val, scope | ENV_USER ) )
+	{
+		case ENV_PERM:
+		{
+			sb_printf( sb_err, _(L"%ls: Tried to change the read-only variable '%ls'\n"), L"set", key );
+			break;
+		}
+	}
+}
+
 /** 
 	Extract the name from a destination argument of the form name[index1 index2...]
 */
@@ -512,7 +524,7 @@ int builtin_set( wchar_t **argv )
 				!erase &&
 				!list )
 			{
-				env_set( name, 0, scope );
+				my_env_set( name, 0, scope );
 				finished = 1;
 			}
 		}
@@ -572,7 +584,7 @@ int builtin_set( wchar_t **argv )
 					else 
 					{
 						fill_buffer_from_list(&result_sb, &val_l);
-						env_set(name, (wchar_t *) result_sb.buff, scope);
+						my_env_set(name, (wchar_t *) result_sb.buff, scope);
 					}     
 				}
 				else
@@ -585,7 +597,7 @@ int builtin_set( wchar_t **argv )
 					fill_buffer_from_list( &result_sb,
 										   &val_l );
 
-					env_set(name,
+					my_env_set(name,
 							(wchar_t *) result_sb.buff,
 							scope);
 				}
diff --git a/env.c b/env.c
index 276de50e..e7b27032 100644
--- a/env.c
+++ b/env.c
@@ -608,7 +608,7 @@ static env_node_t *env_get_node( const wchar_t *key )
 	return 0;
 }
 
-void env_set( const wchar_t *key, 
+int env_set( const wchar_t *key, 
 			  const wchar_t *val, 
 			  int var_mode )
 {
@@ -626,7 +626,7 @@ void env_set( const wchar_t *key,
 	if( (var_mode & ENV_USER ) && 
 		hash_get( &env_read_only, key ) )
 	{
-		return;
+		return ENV_PERM;
 	}
 	
 	if( wcscmp( key, L"umask" ) == 0)
@@ -650,7 +650,7 @@ void env_set( const wchar_t *key,
 		/*
 		  Do not actually create a umask variable, on env_get, it will be calculated dynamically
 		*/
-		return;
+		return 0;
 	}
 
 	/*
@@ -749,7 +749,7 @@ void env_set( const wchar_t *key,
 					node = top;
 					while( node->next && !node->new_scope )
 						node = node->next;
-				
+					
 				}
 			}
 		}
@@ -809,7 +809,8 @@ void env_set( const wchar_t *key,
 	{
 		handle_locale();
 	}
-		
+
+	return 0;
 }
 
 
diff --git a/env.h b/env.h
index bd43e3ca..69679577 100644
--- a/env.h
+++ b/env.h
@@ -42,6 +42,11 @@
 #define ENV_UNIVERSAL 32
 
 /**
+   Error code for trying to alter read-only variable
+*/
+#define ENV_PERM 1
+
+/**
    Initialize environment variable data
 */
 void env_init();
@@ -61,9 +66,15 @@ void env_destroy();
    \param val The value
    \param mode The type of the variable. Can be any combination of ENV_GLOBAL, ENV_LOCAL, ENV_EXPORT and ENV_USER. If mode is zero, the current variable space is searched and the current mode is used. If no current variable with the same name is found, ENV_LOCAL is assumed.
 
+   \returns 0 on suicess or an error code on failiure.
+
+   The current error codes are:
+
+   * ENV_PERM, can only be returned when setting as a user, e.g. ENV_USER is set. This means that the user tried to change a read-only variable.
+
 */
 
-void env_set( const wchar_t *key, 
+int env_set( const wchar_t *key, 
 			  const wchar_t *val,
 			  int mode );