ash: survive failures in $PS1 expansion. Closes 10371

function                                             old     new   delta
expandstr                                            120     209     +89

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 18 insertions, 1 deletions

diff --git a/shell/ash.c b/shell/ash.c
index 39705a350..ef81ea70f 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -12656,7 +12656,24 @@ expandstr(const char *ps, int syntax_type)
 
         saveprompt = doprompt;
         doprompt = 0;
-        readtoken1(pgetc(), syntax_type, FAKEEOFMARK, 0);
+
+        /* readtoken1() might die horribly.
+         * Try a prompt with syntacticallyt wrong command:
+         * PS1='$(date "+%H:%M:%S) > '
+         */
+        {
+                volatile int saveint;
+                struct jmploc *volatile savehandler = exception_handler;
+                struct jmploc jmploc;
+                SAVE_INT(saveint);
+                if (setjmp(jmploc.loc) == 0) {
+                        exception_handler = &jmploc;
+                        readtoken1(pgetc(), syntax_type, FAKEEOFMARK, 0);
+                }
+                exception_handler = savehandler;
+                RESTORE_INT(saveint);
+        }
+
         doprompt = saveprompt;
 
         popfile();