scripts: add option to start an interactive debug shell

Add an option that, when a command fails:
  - starts an interactive shell with the failed command's environment
  - attempts re-execution of the failed command, continues, or aborts
    at user's whim.

Before starting the debug-shell, the backtrace is printed.
When exiting for an abort, the standard error message is printed.

Based on an idea and a patch from: Johannes Stezenbach <js@sig21.net>
    http://sourceware.org/ml/crossgcc/2012-09/msg00144.html

Signed-off-by: Johannes Stezenbach <js@sig21.net>
[yann.morin.1998@free.fr: integrate in the fault handler]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Acked-by: Johannes Stezenbach <js@sig21.net>
Patchwork-Id: 191571
Patchwork-Id: 191668

1 files changed, 19 insertions, 0 deletions

diff --git a/config/global/ct-behave.in b/config/global/ct-behave.in
index bbe4324f..6256a34e 100644
--- a/config/global/ct-behave.in
+++ b/config/global/ct-behave.in
@@ -87,4 +87,23 @@ config NO_OVERIDE_LC_MESSAGES
       
       Say N, please.
 
+config DEBUG_INTERACTIVE
+    bool
+    prompt "Interactive shell on failed commands"
+    help
+      If you say 'y' here, then an interactive shell will be spawned for
+      each failed command.
+      
+      This shell will have the same environment that the failed command
+      was run with, and the working directory will be set to the directory
+      the failed command was run in.
+      
+      After you fix the issue, you can exit the interactive shell with any
+      of these exit codes:
+        1  the issue was fixed, continue the build with the next command
+        2  the issue was fixed, re-run the failed command
+        3  abort the build
+      
+      Note: '2' is only possible for commands run via CT_DoExecLog, though.
+
 endif