use get_local_var_value() rather than getenv() when working with PS1/PS2/HOME, respect the PS2 env var, and make sure that the prompt changes whenever PS1/PS2 changes so we dont have to re-exec the shell to get a changed prompt

1 files changed, 18 insertions, 8 deletions

diff --git a/shell/hush.c b/shell/hush.c
index 56b12cebc..924d826cc 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -795,6 +795,13 @@ static void syntax_error_unexpected_ch(unsigned lineno, char ch)
 #endif
 
 
+#if ENABLE_HUSH_INTERACTIVE
+static void cmdedit_update_prompt(void);
+#else
+# define cmdedit_update_prompt()
+#endif
+
+
 /* Utility functions
  */
 static int glob_needed(const char *s)
@@ -1332,6 +1339,8 @@ static int set_local_var(char *str, int flg_export, int flg_read_only)
  exp:
         if (flg_export == 1)
                 cur->flg_export = 1;
+        if (name_len == 4 && cur->varstr[0] == 'P' && cur->varstr[1] == 'S')
+                cmdedit_update_prompt();
         if (cur->flg_export) {
                 if (flg_export == -1) {
                         cur->flg_export = 0;
@@ -1365,6 +1374,8 @@ static int unset_local_var(const char *name)
                         prev->next = cur->next;
                         debug_printf_env("%s: unsetenv '%s'\n", __func__, cur->varstr);
                         bb_unsetenv(cur->varstr);
+                        if (name_len == 3 && cur->varstr[0] == 'P' && cur->varstr[1] == 'S')
+                                cmdedit_update_prompt();
                         if (!cur->max_len)
                                 free(cur->varstr);
                         free(cur);
@@ -1421,14 +1432,17 @@ static int static_peek(struct in_str *i)
 
 #if ENABLE_HUSH_INTERACTIVE
 
-static void cmdedit_set_initial_prompt(void)
+static void cmdedit_update_prompt(void)
 {
         if (ENABLE_FEATURE_EDITING_FANCY_PROMPT) {
-                G.PS1 = getenv("PS1");
+                G.PS1 = get_local_var_value("PS1");
                 if (G.PS1 == NULL)
                         G.PS1 = "\\w \\$ ";
+                G.PS2 = get_local_var_value("PS2");
         } else
                 G.PS1 = NULL;
+        if (G.PS2 == NULL)
+                G.PS2 = "> ";
 }
 
 static const char* setup_prompt_string(int promptmode)
@@ -6002,11 +6016,7 @@ int hush_main(int argc, char **argv)
         G.global_argv = argv;
         /* Initialize some more globals to non-zero values */
         set_cwd();
-#if ENABLE_HUSH_INTERACTIVE
-        if (ENABLE_FEATURE_EDITING)
-                cmdedit_set_initial_prompt();
-        G.PS2 = "> ";
-#endif
+        cmdedit_update_prompt();
 
         if (setjmp(die_jmp)) {
                 /* xfunc has failed! die die die */
@@ -6334,7 +6344,7 @@ static int builtin_cd(char **argv)
                  * bash says "bash: cd: HOME not set" and does nothing
                  * (exitcode 1)
                  */
-                newdir = getenv("HOME") ? : "/";
+                newdir = get_local_var_value("HOME") ? : "/";
         }
         if (chdir(newdir)) {
                 /* Mimic bash message exactly */