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BASH PATCH REPORT
=================
Bash-Release: 5.0
Patch-ID: bash50-005
Bug-Reported-by: Brad Spencer <bspencer@blackberry.com>
Bug-Reference-ID: <1b993ff2-ce4f-662a-6be4-393457362e47@blackberry.com>
Bug-Reference-URL: http://lists.gnu.org/archive/html/bug-bash/2019-01/msg00250.html
Bug-Description:
In certain cases, bash optimizes out a fork() call too early and prevents
traps from running.
Patch (apply with `patch -p0'):
*** ../bash-5.0-patched/command.h 2018-07-20 21:16:31.000000000 -0400
--- command.h 2019-02-20 11:09:36.000000000 -0500
***************
*** 187,190 ****
--- 188,192 ----
#define CMD_LASTPIPE 0x2000
#define CMD_STDPATH 0x4000 /* use standard path for command lookup */
+ #define CMD_TRY_OPTIMIZING 0x8000 /* try to optimize this simple command */
/* What a command looks like. */
*** ../bash-5.0-patched/builtins/evalstring.c 2018-12-26 11:19:21.000000000 -0500
--- builtins/evalstring.c 2019-01-29 14:15:19.000000000 -0500
***************
*** 101,104 ****
--- 101,113 ----
}
+ int
+ can_optimize_connection (command)
+ COMMAND *command;
+ {
+ return (*bash_input.location.string == '\0' &&
+ (command->value.Connection->connector == AND_AND || command->value.Connection->connector == OR_OR || command->value.Connection->connector == ';') &&
+ command->value.Connection->second->type == cm_simple);
+ }
+
void
optimize_fork (command)
***************
*** 106,110 ****
{
if (command->type == cm_connection &&
! (command->value.Connection->connector == AND_AND || command->value.Connection->connector == OR_OR) &&
should_suppress_fork (command->value.Connection->second))
{
--- 115,120 ----
{
if (command->type == cm_connection &&
! (command->value.Connection->connector == AND_AND || command->value.Connection->connector == OR_OR || command->value.Connection->connector == ';') &&
! (command->value.Connection->second->flags & CMD_TRY_OPTIMIZING) &&
should_suppress_fork (command->value.Connection->second))
{
***************
*** 413,418 ****
command->value.Simple->flags |= CMD_NO_FORK;
}
! else if (command->type == cm_connection)
! optimize_fork (command);
#endif /* ONESHOT */
--- 423,438 ----
command->value.Simple->flags |= CMD_NO_FORK;
}
!
! /* Can't optimize forks out here execept for simple commands.
! This knows that the parser sets up commands as left-side heavy
! (&& and || are left-associative) and after the single parse,
! if we are at the end of the command string, the last in a
! series of connection commands is
! command->value.Connection->second. */
! else if (command->type == cm_connection && can_optimize_connection (command))
! {
! command->value.Connection->second->flags |= CMD_TRY_OPTIMIZING;
! command->value.Connection->second->value.Simple->flags |= CMD_TRY_OPTIMIZING;
! }
#endif /* ONESHOT */
*** ../bash-5.0-patched/execute_cmd.c 2018-12-05 09:05:14.000000000 -0500
--- execute_cmd.c 2019-01-25 15:59:00.000000000 -0500
***************
*** 2768,2771 ****
--- 2768,2773 ----
(exec_result != EXECUTION_SUCCESS)))
{
+ optimize_fork (command);
+
second = command->value.Connection->second;
if (ignore_return && second)
*** ../bash-5.0/patchlevel.h 2016-06-22 14:51:03.000000000 -0400
--- patchlevel.h 2016-10-01 11:01:28.000000000 -0400
***************
*** 26,30 ****
looks for to find the patch level (for the sccs version string). */
! #define PATCHLEVEL 4
#endif /* _PATCHLEVEL_H_ */
--- 26,30 ----
looks for to find the patch level (for the sccs version string). */
! #define PATCHLEVEL 5
#endif /* _PATCHLEVEL_H_ */
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