From f81331808f9b2dd8872e335a88995296bd169d0a Mon Sep 17 00:00:00 2001
From: Philipp Maier <pmaier@sysmocom.de>
Date: Mon, 26 Aug 2024 15:41:40 +0200
Subject: [PATCH] pySim-shell: rework startup procedure and introduce non
 interactive mode

When pySim-shell is used in a scripted environment, we may easily get trapped in
the pySim-shell prompt. This may happen in particular in case the script file
is not executed due to problem with the reader initialization. In such a case
pySim-shell will not exit automatically and the shellscript that was calling
pySim-shell will stall indefinetly.

To make the use of pySim-shell more reliable in scripted environments, let's
add a --noprompt option that ensures the interactive mode is never entered.
Let's also exit with an appropriate return code in case of initialization
errors, so that the calling script can know that something went wrong.

Related: OS#6531
Change-Id: I07ecb27b37e2573629981a0d032cc95cd156be7e
---
 pySim-shell.py | 55 +++++++++++++++++++++++++++++++++-----------------
 1 file changed, 36 insertions(+), 19 deletions(-)

diff --git a/pySim-shell.py b/pySim-shell.py
index d3f9d910..16a6b975 100755
--- a/pySim-shell.py
+++ b/pySim-shell.py
@@ -1028,6 +1028,8 @@ global_group.add_argument('--csv-column-key', metavar='FIELD:AES_KEY_HEX', defau
                           help='per-CSV-column AES transport key')
 global_group.add_argument("--card_handler", dest="card_handler_config", metavar="FILE",
                           help="Use automatic card handling machine")
+global_group.add_argument("--noprompt", help="Run in non interactive mode",
+                          action='store_true', default=False)
 
 adm_group = global_group.add_mutually_exclusive_group()
 adm_group.add_argument('-a', '--pin-adm', metavar='PIN_ADM1', dest='pin_adm', default=None,
@@ -1043,22 +1045,15 @@ option_parser.add_argument('command_args', nargs=argparse.REMAINDER,
 
 if __name__ == '__main__':
 
-    # Parse options
+    startup_errors = False
     opts = option_parser.parse_args()
 
-    # If a script file is specified, be sure that it actually exists
-    if opts.script:
-        if not os.access(opts.script, os.R_OK):
-            print("Invalid script file!")
-            sys.exit(2)
-
+    # Register csv-file as card data provider, either from specified CSV
+    # or from CSV file in home directory
     csv_column_keys = {}
     for par in opts.csv_column_key:
         name, key = par.split(':')
         csv_column_keys[name] = key
-
-    # Register csv-file as card data provider, either from specified CSV
-    # or from CSV file in home directory
     csv_default = str(Path.home()) + "/.osmocom/pysim/card_data.csv"
     if opts.csv:
         card_key_provider_register(CardKeyProviderCsv(opts.csv, csv_column_keys))
@@ -1079,18 +1074,18 @@ if __name__ == '__main__':
     # able to tolerate and recover from that.
     try:
         rs, card = init_card(sl)
-        app = PysimApp(card, rs, sl, ch, opts.script)
+        app = PysimApp(card, rs, sl, ch)
     except:
+        startup_errors = True
         print("Card initialization (%s) failed with an exception:" % str(sl))
         print("---------------------8<---------------------")
         traceback.print_exc()
         print("---------------------8<---------------------")
-        print("(you may still try to recover from this manually by using the 'equip' command.)")
-        print(" it should also be noted that some readers may behave strangely when no card")
-        print(" is inserted.)")
-        print("")
-        if opts.script:
-            print("will not execute startup script due to card initialization errors!")
+        if not opts.noprompt:
+            print("(you may still try to recover from this manually by using the 'equip' command.)")
+            print(" it should also be noted that some readers may behave strangely when no card")
+            print(" is inserted.)")
+            print("")
         app = PysimApp(None, None, sl, ch)
 
     # If the user supplies an ADM PIN at via commandline args authenticate
@@ -1102,9 +1097,31 @@ if __name__ == '__main__':
         try:
             card._scc.verify_chv(card._adm_chv_num, h2b(pin_adm))
         except Exception as e:
+            startup_errors = True
+            print("ADM verification (%s) failed with an exception:" % str(pin_adm))
+            print("---------------------8<---------------------")
             print(e)
+            print("---------------------8<---------------------")
 
+    # Run optional command
     if opts.command:
-        app.onecmd_plus_hooks('{} {}'.format(opts.command, ' '.join(opts.command_args)))
-    else:
+        if not startup_errors:
+            app.onecmd_plus_hooks('{} {}'.format(opts.command, ' '.join(opts.command_args)))
+        else:
+            print("Errors during startup, refusing to execute command (%s)" % opts.command)
+
+    # Run optional script file
+    if opts.script:
+        if not startup_errors:
+            if not os.access(opts.script, os.R_OK):
+                print("Error: script file (%s) not readable!" % opts.script)
+                startup_errors = True
+            else:
+                app.onecmd_plus_hooks('{} {}'.format('run_script', opts.script), add_to_history = False)
+        else:
+            print("Errors during startup, refusing to execute script (%s)" % opts.script)
+
+    if not opts.noprompt:
         app.cmdloop()
+    elif startup_errors:
+        sys.exit(2)