gpg: Allow to freeze faked system time.

* g10/gpg.c (main): If the parameter for --faked-system-time
ends with a '!', freeze time at the specified point.
* common/gettime.c (gnupg_set_time): Allow to freeze the time
at an arbitrary time instead of only the current time.
* doc/gpg.texi: Update documentation for --faked-system-time.
--

This patch allows the user to modify the behavior of the
--faked-system-time option: by appending a '!' to the parameter,
time in GnuPG will be frozen at the specified time, instead of
advancing normally from that time onward.

Signed-off-by: Damien Goutte-Gattat <dgouttegattat@incenp.org>

1 files changed, 12 insertions, 2 deletions

diff --git a/g10/gpg.c b/g10/gpg.c
index 8c5b50589..f9039ae09 100644
--- a/g10/gpg.c
+++ b/g10/gpg.c
@@ -3493,10 +3493,20 @@ main (int argc, char **argv)
 
           case oFakedSystemTime:
             {
-              time_t faked_time = isotime2epoch (pargs.r.ret_str);
+              size_t len = strlen (pargs.r.ret_str);
+              int freeze = 0;
+              time_t faked_time;
+
+              if (len > 0 && pargs.r.ret_str[len-1] == '!')
+                {
+                  freeze = 1;
+                  pargs.r.ret_str[len-1] = '\0';
+                }
+
+              faked_time = isotime2epoch (pargs.r.ret_str);
               if (faked_time == (time_t)(-1))
                 faked_time = (time_t)strtoul (pargs.r.ret_str, NULL, 10);
-              gnupg_set_time (faked_time, 0);
+              gnupg_set_time (faked_time, freeze);
             }
             break;