Imported from ../bash-3.1.tar.gz.

[platform/upstream/bash.git] / builtins / trap.def

diff --git a/builtins/trap.def b/builtins/trap.def
index 933bd25..669bea7 100644 (file)
--- a/builtins/trap.def
+++ b/builtins/trap.def
@@ -1,7 +1,7 @@
 This file is trap.def, from which is created trap.c.
 It implements the builtin "trap" in Bash.
 
-Copyright (C) 1987, 1989, 1991 Free Software Foundation, Inc.
+Copyright (C) 1987-2005 Free Software Foundation, Inc.
 
 This file is part of GNU Bash, the Bourne Again SHell.
 
@@ -23,20 +23,21 @@ $PRODUCES trap.c
 
 $BUILTIN trap
 $FUNCTION trap_builtin
-$SHORT_DOC trap [arg] [signal_spec ...] or trap -l
+$SHORT_DOC trap [-lp] [arg signal_spec ...]
 The command ARG is to be read and executed when the shell receives
-signal(s) SIGNAL_SPEC.  If ARG is absent all specified signals are
-reset to their original values.  If ARG is the null string each
-SIGNAL_SPEC is ignored by the shell and by the commands it invokes.
-If a SIGNAL_SPEC is EXIT (0) the command ARG is executed on exit from
-the shell.  If a SIGNAL_SPEC is DEBUG, ARG is executed after every
-command.  If ARG is `-p' then the trap commands associated with
-each SIGNAL_SPEC are displayed.  If no arguments are supplied or if
-only `-p' is given, trap prints the list of commands associated with
-each signal number.  Each SIGNAL_SPEC is either a signal name in <signal.h>
-or a signal number.  `trap -l' prints a list of signal names and their
-corresponding numbers.  Note that a signal can be sent to the shell
-with "kill -signal $$".
+signal(s) SIGNAL_SPEC.  If ARG is absent (and a single SIGNAL_SPEC
+is supplied) or `-', each specified signal is reset to its original
+value.  If ARG is the null string each SIGNAL_SPEC is ignored by the
+shell and by the commands it invokes.  If a SIGNAL_SPEC is EXIT (0)
+the command ARG is executed on exit from the shell.  If a SIGNAL_SPEC
+is DEBUG, ARG is executed after every simple command.  If the`-p' option
+is supplied then the trap commands associated with each SIGNAL_SPEC are
+displayed.  If no arguments are supplied or if only `-p' is given, trap
+prints the list of commands associated with each signal.  Each SIGNAL_SPEC
+is either a signal name in <signal.h> or a signal number.  Signal names
+are case insensitive and the SIG prefix is optional.  `trap -l' prints
+a list of signal names and their corresponding numbers.  Note that a
+signal can be sent to the shell with "kill -signal $$".
 $END
 
 #include <config.h>
@@ -86,7 +87,7 @@ int
 trap_builtin (list)
      WORD_LIST *list;
 {
-  int list_signal_names, display, result, opt;
+  int list_signal_names, display, result, opt, first_signal;
 
   list_signal_names = display = 0;
   result = EXECUTION_SUCCESS;
@@ -108,6 +109,8 @@ trap_builtin (list)
     }
   list = loptend;
 
+  opt = DSIG_NOCASE|DSIG_SIGPREFIX;    /* flags for decode_signal */
+
   if (list_signal_names)
     return (display_signal_list ((WORD_LIST *)NULL, 1));
   else if (display || list == 0)
@@ -115,17 +118,31 @@ trap_builtin (list)
   else
     {
       char *first_arg;
-      int operation, sig;
+      int operation, sig, first_signal;
 
       operation = SET;
       first_arg = list->word->word;
-      if (first_arg && *first_arg && (*first_arg != '-' || first_arg[1]) &&
-               signal_object_p (first_arg))
+      first_signal = first_arg && *first_arg && all_digits (first_arg) && signal_object_p (first_arg, opt);
+
+      /* Backwards compatibility */
+      if (first_signal)
+       operation = REVERT;
+      /* When in posix mode, the historical behavior of looking for a
+        missing first argument is disabled.  To revert to the original
+        signal handling disposition, use `-' as the first argument. */
+      else if (posixly_correct == 0 && first_arg && *first_arg &&
+               (*first_arg != '-' || first_arg[1]) &&
+               signal_object_p (first_arg, opt) && list->next == 0)
        operation = REVERT;
       else
        {
          list = list->next;
-         if (*first_arg == '\0')
+         if (list == 0)
+           {
+             builtin_usage ();
+             return (EX_USAGE);
+           }
+         else if (*first_arg == '\0')
            operation = IGNORE;
          else if (first_arg[0] == '-' && !first_arg[1])
            operation = REVERT;
@@ -133,12 +150,11 @@ trap_builtin (list)
 
       while (list)
        {
-         sig = decode_signal (list->word->word);
+         sig = decode_signal (list->word->word, opt);
 
          if (sig == NO_SIG)
            {
-             builtin_error ("%s: not a signal specification",
-                            list->word->word);
+             sh_invalidsig (list->word->word);
              result = EXECUTION_FAILURE;
            }
          else
@@ -198,7 +214,6 @@ showtrap (i)
   char *t, *p, *sn;
 
   p = trap_list[i];
-
   if (p == (char *)DEFAULT_SIG)
     return;
 
@@ -236,11 +251,11 @@ display_traps (list)
 
   for (result = EXECUTION_SUCCESS; list; list = list->next)
     {
-      i = decode_signal (list->word->word);
+      i = decode_signal (list->word->word, DSIG_NOCASE|DSIG_SIGPREFIX);
       if (i == NO_SIG)
        {
+         sh_invalidsig (list->word->word);
          result = EXECUTION_FAILURE;
-         builtin_error ("%s: not a signal specification", list->word->word);
        }
       else
        showtrap (i);