execute_cmd.c.orig [plain text]
/* execute_cmd.c -- Execute a COMMAND structure. */
/* Copyright (C) 1987-2007 Free Software Foundation, Inc.
This file is part of GNU Bash, the Bourne Again SHell.
Bash is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
Bash is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
License for more details.
You should have received a copy of the GNU General Public License
along with Bash; see the file COPYING. If not, write to the Free
Software Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. */
#include "config.h"
#if !defined (__GNUC__) && !defined (HAVE_ALLOCA_H) && defined (_AIX)
#pragma alloca
#endif /* _AIX && RISC6000 && !__GNUC__ */
#include <stdio.h>
#include "chartypes.h"
#include "bashtypes.h"
#if !defined (_MINIX) && defined (HAVE_SYS_FILE_H)
# include <sys/file.h>
#endif
#include "filecntl.h"
#include "posixstat.h"
#include <signal.h>
#ifndef _MINIX
# include <sys/param.h>
#endif
#if defined (HAVE_UNISTD_H)
# include <unistd.h>
#endif
#include "posixtime.h"
#if defined (HAVE_SYS_RESOURCE_H) && !defined (RLIMTYPE)
# include <sys/resource.h>
#endif
#if defined (HAVE_SYS_TIMES_H) && defined (HAVE_TIMES)
# include <sys/times.h>
#endif
#include <errno.h>
#if !defined (errno)
extern int errno;
#endif
#include "bashansi.h"
#include "bashintl.h"
#include "memalloc.h"
#include "shell.h"
#include <y.tab.h> /* use <...> so we pick it up from the build directory */
#include "flags.h"
#include "builtins.h"
#include "hashlib.h"
#include "jobs.h"
#include "execute_cmd.h"
#include "findcmd.h"
#include "redir.h"
#include "trap.h"
#include "pathexp.h"
#include "hashcmd.h"
#if defined (COND_COMMAND)
# include "test.h"
#endif
#include "builtins/common.h"
#include "builtins/builtext.h" /* list of builtins */
#include <glob/strmatch.h>
#include <tilde/tilde.h>
#if defined (BUFFERED_INPUT)
# include "input.h"
#endif
#if defined (ALIAS)
# include "alias.h"
#endif
#if defined (HISTORY)
# include "bashhist.h"
#endif
extern int posixly_correct;
extern int breaking, continuing, loop_level;
extern int expand_aliases;
extern int parse_and_execute_level, running_trap;
extern int command_string_index, line_number;
extern int dot_found_in_search;
extern int already_making_children;
extern int tempenv_assign_error;
extern char *the_printed_command, *shell_name;
extern pid_t last_command_subst_pid;
extern sh_builtin_func_t *last_shell_builtin, *this_shell_builtin;
extern char **subshell_argv, **subshell_envp;
extern int subshell_argc;
#if 0
extern char *glob_argv_flags;
#endif
extern int close __P((int));
/* Static functions defined and used in this file. */
static void close_pipes __P((int, int));
static void do_piping __P((int, int));
static void bind_lastarg __P((char *));
static int shell_control_structure __P((enum command_type));
static void cleanup_redirects __P((REDIRECT *));
#if defined (JOB_CONTROL)
static int restore_signal_mask __P((sigset_t *));
#endif
static void async_redirect_stdin __P((void));
static int builtin_status __P((int));
static int execute_for_command __P((FOR_COM *));
#if defined (SELECT_COMMAND)
static int print_index_and_element __P((int, int, WORD_LIST *));
static void indent __P((int, int));
static void print_select_list __P((WORD_LIST *, int, int, int));
static char *select_query __P((WORD_LIST *, int, char *, int));
static int execute_select_command __P((SELECT_COM *));
#endif
#if defined (DPAREN_ARITHMETIC)
static int execute_arith_command __P((ARITH_COM *));
#endif
#if defined (COND_COMMAND)
static int execute_cond_node __P((COND_COM *));
static int execute_cond_command __P((COND_COM *));
#endif
#if defined (COMMAND_TIMING)
static int mkfmt __P((char *, int, int, time_t, int));
static void print_formatted_time __P((FILE *, char *,
time_t, int, time_t, int,
time_t, int, int));
static int time_command __P((COMMAND *, int, int, int, struct fd_bitmap *));
#endif
#if defined (ARITH_FOR_COMMAND)
static intmax_t eval_arith_for_expr __P((WORD_LIST *, int *));
static int execute_arith_for_command __P((ARITH_FOR_COM *));
#endif
static int execute_case_command __P((CASE_COM *));
static int execute_while_command __P((WHILE_COM *));
static int execute_until_command __P((WHILE_COM *));
static int execute_while_or_until __P((WHILE_COM *, int));
static int execute_if_command __P((IF_COM *));
static int execute_null_command __P((REDIRECT *, int, int, int));
static void fix_assignment_words __P((WORD_LIST *));
static int execute_simple_command __P((SIMPLE_COM *, int, int, int, struct fd_bitmap *));
static int execute_builtin __P((sh_builtin_func_t *, WORD_LIST *, int, int));
static int execute_function __P((SHELL_VAR *, WORD_LIST *, int, struct fd_bitmap *, int, int));
static int execute_builtin_or_function __P((WORD_LIST *, sh_builtin_func_t *,
SHELL_VAR *,
REDIRECT *, struct fd_bitmap *, int));
static void execute_subshell_builtin_or_function __P((WORD_LIST *, REDIRECT *,
sh_builtin_func_t *,
SHELL_VAR *,
int, int, int,
struct fd_bitmap *,
int));
static void execute_disk_command __P((WORD_LIST *, REDIRECT *, char *,
int, int, int, struct fd_bitmap *, int));
static char *getinterp __P((char *, int, int *));
static void initialize_subshell __P((void));
static int execute_in_subshell __P((COMMAND *, int, int, int, struct fd_bitmap *));
static int execute_pipeline __P((COMMAND *, int, int, int, struct fd_bitmap *));
static int execute_connection __P((COMMAND *, int, int, int, struct fd_bitmap *));
static int execute_intern_function __P((WORD_DESC *, COMMAND *));
/* The line number that the currently executing function starts on. */
static int function_line_number;
/* Set to 1 if fd 0 was the subject of redirection to a subshell. Global
so that reader_loop can set it to zero before executing a command. */
int stdin_redir;
/* The name of the command that is currently being executed.
`test' needs this, for example. */
char *this_command_name;
/* The printed representation of the currently-executing command (same as
the_printed_command), except when a trap is being executed. Useful for
a debugger to know where exactly the program is currently executing. */
char *the_printed_command_except_trap;
static COMMAND *currently_executing_command;
struct stat SB; /* used for debugging */
static int special_builtin_failed;
/* XXX - set to 1 if we're running the DEBUG trap and we want to show the line
number containing the function name. Used by executing_line_number to
report the correct line number. Kind of a hack. */
static int showing_function_line;
static int line_number_for_err_trap;
/* For catching RETURN in a function. */
int return_catch_flag;
int return_catch_value;
procenv_t return_catch;
/* The value returned by the last synchronous command. */
int last_command_exit_value;
/* Whether or not the last command (corresponding to last_command_exit_value)
was terminated by a signal, and, if so, which one. */
int last_command_exit_signal;
/* The list of redirections to perform which will undo the redirections
that I made in the shell. */
REDIRECT *redirection_undo_list = (REDIRECT *)NULL;
/* The list of redirections to perform which will undo the internal
redirections performed by the `exec' builtin. These are redirections
that must be undone even when exec discards redirection_undo_list. */
REDIRECT *exec_redirection_undo_list = (REDIRECT *)NULL;
/* Non-zero if we have just forked and are currently running in a subshell
environment. */
int subshell_environment;
/* Count of nested subshells, like SHLVL. Available via $BASH_SUBSHELL */
int subshell_level = 0;
/* Currently-executing shell function. */
SHELL_VAR *this_shell_function;
/* If non-zero, matches in case and [[ ... ]] are case-insensitive */
int match_ignore_case = 0;
struct fd_bitmap *current_fds_to_close = (struct fd_bitmap *)NULL;
#define FD_BITMAP_DEFAULT_SIZE 32
/* Functions to allocate and deallocate the structures used to pass
information from the shell to its children about file descriptors
to close. */
struct fd_bitmap *
new_fd_bitmap (size)
int size;
{
struct fd_bitmap *ret;
ret = (struct fd_bitmap *)xmalloc (sizeof (struct fd_bitmap));
ret->size = size;
if (size)
{
ret->bitmap = (char *)xmalloc (size);
memset (ret->bitmap, '\0', size);
}
else
ret->bitmap = (char *)NULL;
return (ret);
}
void
dispose_fd_bitmap (fdbp)
struct fd_bitmap *fdbp;
{
FREE (fdbp->bitmap);
free (fdbp);
}
void
close_fd_bitmap (fdbp)
struct fd_bitmap *fdbp;
{
register int i;
if (fdbp)
{
for (i = 0; i < fdbp->size; i++)
if (fdbp->bitmap[i])
{
close (i);
fdbp->bitmap[i] = 0;
}
}
}
/* Return the line number of the currently executing command. */
int
executing_line_number ()
{
if (executing && showing_function_line == 0 &&
(variable_context == 0 || interactive_shell == 0) &&
currently_executing_command)
{
#if defined (COND_COMMAND)
if (currently_executing_command->type == cm_cond)
return currently_executing_command->value.Cond->line;
#endif
#if defined (DPAREN_ARITHMETIC)
else if (currently_executing_command->type == cm_arith)
return currently_executing_command->value.Arith->line;
#endif
#if defined (ARITH_FOR_COMMAND)
else if (currently_executing_command->type == cm_arith_for)
return currently_executing_command->value.ArithFor->line;
#endif
return line_number;
}
else
return line_number;
}
/* Execute the command passed in COMMAND. COMMAND is exactly what
read_command () places into GLOBAL_COMMAND. See "command.h" for the
details of the command structure.
EXECUTION_SUCCESS or EXECUTION_FAILURE are the only possible
return values. Executing a command with nothing in it returns
EXECUTION_SUCCESS. */
int
execute_command (command)
COMMAND *command;
{
struct fd_bitmap *bitmap;
int result;
current_fds_to_close = (struct fd_bitmap *)NULL;
bitmap = new_fd_bitmap (FD_BITMAP_DEFAULT_SIZE);
begin_unwind_frame ("execute-command");
add_unwind_protect (dispose_fd_bitmap, (char *)bitmap);
/* Just do the command, but not asynchronously. */
result = execute_command_internal (command, 0, NO_PIPE, NO_PIPE, bitmap);
dispose_fd_bitmap (bitmap);
discard_unwind_frame ("execute-command");
#if defined (PROCESS_SUBSTITUTION)
/* don't unlink fifos if we're in a shell function; wait until the function
returns. */
if (variable_context == 0)
unlink_fifo_list ();
#endif /* PROCESS_SUBSTITUTION */
QUIT;
return (result);
}
/* Return 1 if TYPE is a shell control structure type. */
static int
shell_control_structure (type)
enum command_type type;
{
switch (type)
{
#if defined (ARITH_FOR_COMMAND)
case cm_arith_for:
#endif
#if defined (SELECT_COMMAND)
case cm_select:
#endif
#if defined (DPAREN_ARITHMETIC)
case cm_arith:
#endif
#if defined (COND_COMMAND)
case cm_cond:
#endif
case cm_case:
case cm_while:
case cm_until:
case cm_if:
case cm_for:
case cm_group:
case cm_function_def:
return (1);
default:
return (0);
}
}
/* A function to use to unwind_protect the redirection undo list
for loops. */
static void
cleanup_redirects (list)
REDIRECT *list;
{
do_redirections (list, RX_ACTIVE);
dispose_redirects (list);
}
#if 0
/* Function to unwind_protect the redirections for functions and builtins. */
static void
cleanup_func_redirects (list)
REDIRECT *list;
{
do_redirections (list, RX_ACTIVE);
}
#endif
void
dispose_exec_redirects ()
{
if (exec_redirection_undo_list)
{
dispose_redirects (exec_redirection_undo_list);
exec_redirection_undo_list = (REDIRECT *)NULL;
}
}
#if defined (JOB_CONTROL)
/* A function to restore the signal mask to its proper value when the shell
is interrupted or errors occur while creating a pipeline. */
static int
restore_signal_mask (set)
sigset_t *set;
{
return (sigprocmask (SIG_SETMASK, set, (sigset_t *)NULL));
}
#endif /* JOB_CONTROL */
#ifdef DEBUG
/* A debugging function that can be called from gdb, for instance. */
void
open_files ()
{
register int i;
int f, fd_table_size;
fd_table_size = getdtablesize ();
fprintf (stderr, "pid %ld open files:", (long)getpid ());
for (i = 3; i < fd_table_size; i++)
{
if ((f = fcntl (i, F_GETFD, 0)) != -1)
fprintf (stderr, " %d (%s)", i, f ? "close" : "open");
}
fprintf (stderr, "\n");
}
#endif
static void
async_redirect_stdin ()
{
int fd;
fd = open ("/dev/null", O_RDONLY);
if (fd > 0)
{
dup2 (fd, 0);
close (fd);
}
else if (fd < 0)
internal_error (_("cannot redirect standard input from /dev/null: %s"), strerror (errno));
}
#define DESCRIBE_PID(pid) do { if (interactive) describe_pid (pid); } while (0)
/* Execute the command passed in COMMAND, perhaps doing it asynchrounously.
COMMAND is exactly what read_command () places into GLOBAL_COMMAND.
ASYNCHROUNOUS, if non-zero, says to do this command in the background.
PIPE_IN and PIPE_OUT are file descriptors saying where input comes
from and where it goes. They can have the value of NO_PIPE, which means
I/O is stdin/stdout.
FDS_TO_CLOSE is a list of file descriptors to close once the child has
been forked. This list often contains the unusable sides of pipes, etc.
EXECUTION_SUCCESS or EXECUTION_FAILURE are the only possible
return values. Executing a command with nothing in it returns
EXECUTION_SUCCESS. */
int
execute_command_internal (command, asynchronous, pipe_in, pipe_out,
fds_to_close)
COMMAND *command;
int asynchronous;
int pipe_in, pipe_out;
struct fd_bitmap *fds_to_close;
{
int exec_result, invert, ignore_return, was_error_trap;
REDIRECT *my_undo_list, *exec_undo_list;
volatile int last_pid;
volatile int save_line_number;
#if 0
if (command == 0 || breaking || continuing || read_but_dont_execute)
return (EXECUTION_SUCCESS);
#else
if (breaking || continuing)
return (last_command_exit_value);
if (command == 0 || read_but_dont_execute)
return (EXECUTION_SUCCESS);
#endif
QUIT;
run_pending_traps ();
#if 0
if (running_trap == 0)
#endif
currently_executing_command = command;
invert = (command->flags & CMD_INVERT_RETURN) != 0;
/* If we're inverting the return value and `set -e' has been executed,
we don't want a failing command to inadvertently cause the shell
to exit. */
if (exit_immediately_on_error && invert) /* XXX */
command->flags |= CMD_IGNORE_RETURN; /* XXX */
exec_result = EXECUTION_SUCCESS;
/* If a command was being explicitly run in a subshell, or if it is
a shell control-structure, and it has a pipe, then we do the command
in a subshell. */
if (command->type == cm_subshell && (command->flags & CMD_NO_FORK))
return (execute_in_subshell (command, asynchronous, pipe_in, pipe_out, fds_to_close));
if (command->type == cm_subshell ||
(command->flags & (CMD_WANT_SUBSHELL|CMD_FORCE_SUBSHELL)) ||
(shell_control_structure (command->type) &&
(pipe_out != NO_PIPE || pipe_in != NO_PIPE || asynchronous)))
{
pid_t paren_pid;
/* Fork a subshell, turn off the subshell bit, turn off job
control and call execute_command () on the command again. */
paren_pid = make_child (savestring (make_command_string (command)),
asynchronous);
if (paren_pid == 0)
exit (execute_in_subshell (command, asynchronous, pipe_in, pipe_out, fds_to_close));
/* NOTREACHED */
else
{
close_pipes (pipe_in, pipe_out);
#if defined (PROCESS_SUBSTITUTION) && defined (HAVE_DEV_FD)
unlink_fifo_list ();
#endif
/* If we are part of a pipeline, and not the end of the pipeline,
then we should simply return and let the last command in the
pipe be waited for. If we are not in a pipeline, or are the
last command in the pipeline, then we wait for the subshell
and return its exit status as usual. */
if (pipe_out != NO_PIPE)
return (EXECUTION_SUCCESS);
stop_pipeline (asynchronous, (COMMAND *)NULL);
if (asynchronous == 0)
{
last_command_exit_value = wait_for (paren_pid);
/* If we have to, invert the return value. */
if (invert)
exec_result = ((last_command_exit_value == EXECUTION_SUCCESS)
? EXECUTION_FAILURE
: EXECUTION_SUCCESS);
else
exec_result = last_command_exit_value;
return (last_command_exit_value = exec_result);
}
else
{
DESCRIBE_PID (paren_pid);
run_pending_traps ();
return (EXECUTION_SUCCESS);
}
}
}
#if defined (COMMAND_TIMING)
if (command->flags & CMD_TIME_PIPELINE)
{
if (asynchronous)
{
command->flags |= CMD_FORCE_SUBSHELL;
exec_result = execute_command_internal (command, 1, pipe_in, pipe_out, fds_to_close);
}
else
{
exec_result = time_command (command, asynchronous, pipe_in, pipe_out, fds_to_close);
#if 0
if (running_trap == 0)
#endif
currently_executing_command = (COMMAND *)NULL;
}
return (exec_result);
}
#endif /* COMMAND_TIMING */
if (shell_control_structure (command->type) && command->redirects)
stdin_redir = stdin_redirects (command->redirects);
/* Handle WHILE FOR CASE etc. with redirections. (Also '&' input
redirection.) */
if (do_redirections (command->redirects, RX_ACTIVE|RX_UNDOABLE) != 0)
{
cleanup_redirects (redirection_undo_list);
redirection_undo_list = (REDIRECT *)NULL;
dispose_exec_redirects ();
return (last_command_exit_value = EXECUTION_FAILURE);
}
if (redirection_undo_list)
{
my_undo_list = (REDIRECT *)copy_redirects (redirection_undo_list);
dispose_redirects (redirection_undo_list);
redirection_undo_list = (REDIRECT *)NULL;
}
else
my_undo_list = (REDIRECT *)NULL;
if (exec_redirection_undo_list)
{
exec_undo_list = (REDIRECT *)copy_redirects (exec_redirection_undo_list);
dispose_redirects (exec_redirection_undo_list);
exec_redirection_undo_list = (REDIRECT *)NULL;
}
else
exec_undo_list = (REDIRECT *)NULL;
if (my_undo_list || exec_undo_list)
begin_unwind_frame ("loop_redirections");
if (my_undo_list)
add_unwind_protect ((Function *)cleanup_redirects, my_undo_list);
if (exec_undo_list)
add_unwind_protect ((Function *)dispose_redirects, exec_undo_list);
ignore_return = (command->flags & CMD_IGNORE_RETURN) != 0;
QUIT;
switch (command->type)
{
case cm_simple:
{
save_line_number = line_number;
/* We can't rely on variables retaining their values across a
call to execute_simple_command if a longjmp occurs as the
result of a `return' builtin. This is true for sure with gcc. */
#if defined (RECYCLES_PIDS)
last_made_pid = NO_PID;
#endif
last_pid = last_made_pid;
was_error_trap = signal_is_trapped (ERROR_TRAP) && signal_is_ignored (ERROR_TRAP) == 0;
if (ignore_return && command->value.Simple)
command->value.Simple->flags |= CMD_IGNORE_RETURN;
if (command->flags & CMD_STDIN_REDIR)
command->value.Simple->flags |= CMD_STDIN_REDIR;
line_number_for_err_trap = line_number = command->value.Simple->line;
exec_result =
execute_simple_command (command->value.Simple, pipe_in, pipe_out,
asynchronous, fds_to_close);
line_number = save_line_number;
/* The temporary environment should be used for only the simple
command immediately following its definition. */
dispose_used_env_vars ();
#if (defined (ultrix) && defined (mips)) || defined (C_ALLOCA)
/* Reclaim memory allocated with alloca () on machines which
may be using the alloca emulation code. */
(void) alloca (0);
#endif /* (ultrix && mips) || C_ALLOCA */
/* If we forked to do the command, then we must wait_for ()
the child. */
/* XXX - this is something to watch out for if there are problems
when the shell is compiled without job control. */
if (already_making_children && pipe_out == NO_PIPE &&
last_made_pid != last_pid)
{
stop_pipeline (asynchronous, (COMMAND *)NULL);
if (asynchronous)
{
DESCRIBE_PID (last_made_pid);
}
else
#if !defined (JOB_CONTROL)
/* Do not wait for asynchronous processes started from
startup files. */
if (last_made_pid != last_asynchronous_pid)
#endif
/* When executing a shell function that executes other
commands, this causes the last simple command in
the function to be waited for twice. This also causes
subshells forked to execute builtin commands (e.g., in
pipelines) to be waited for twice. */
exec_result = wait_for (last_made_pid);
}
}
if (was_error_trap && ignore_return == 0 && invert == 0 && exec_result != EXECUTION_SUCCESS)
{
last_command_exit_value = exec_result;
run_error_trap ();
}
if (ignore_return == 0 && invert == 0 &&
((posixly_correct && interactive == 0 && special_builtin_failed) ||
(exit_immediately_on_error && (exec_result != EXECUTION_SUCCESS))))
{
last_command_exit_value = exec_result;
run_pending_traps ();
jump_to_top_level (ERREXIT);
}
break;
case cm_for:
if (ignore_return)
command->value.For->flags |= CMD_IGNORE_RETURN;
exec_result = execute_for_command (command->value.For);
break;
#if defined (ARITH_FOR_COMMAND)
case cm_arith_for:
if (ignore_return)
command->value.ArithFor->flags |= CMD_IGNORE_RETURN;
exec_result = execute_arith_for_command (command->value.ArithFor);
break;
#endif
#if defined (SELECT_COMMAND)
case cm_select:
if (ignore_return)
command->value.Select->flags |= CMD_IGNORE_RETURN;
exec_result = execute_select_command (command->value.Select);
break;
#endif
case cm_case:
if (ignore_return)
command->value.Case->flags |= CMD_IGNORE_RETURN;
exec_result = execute_case_command (command->value.Case);
break;
case cm_while:
if (ignore_return)
command->value.While->flags |= CMD_IGNORE_RETURN;
exec_result = execute_while_command (command->value.While);
break;
case cm_until:
if (ignore_return)
command->value.While->flags |= CMD_IGNORE_RETURN;
exec_result = execute_until_command (command->value.While);
break;
case cm_if:
if (ignore_return)
command->value.If->flags |= CMD_IGNORE_RETURN;
exec_result = execute_if_command (command->value.If);
break;
case cm_group:
/* This code can be executed from either of two paths: an explicit
'{}' command, or via a function call. If we are executed via a
function call, we have already taken care of the function being
executed in the background (down there in execute_simple_command ()),
and this command should *not* be marked as asynchronous. If we
are executing a regular '{}' group command, and asynchronous == 1,
we must want to execute the whole command in the background, so we
need a subshell, and we want the stuff executed in that subshell
(this group command) to be executed in the foreground of that
subshell (i.e. there will not be *another* subshell forked).
What we do is to force a subshell if asynchronous, and then call
execute_command_internal again with asynchronous still set to 1,
but with the original group command, so the printed command will
look right.
The code above that handles forking off subshells will note that
both subshell and async are on, and turn off async in the child
after forking the subshell (but leave async set in the parent, so
the normal call to describe_pid is made). This turning off
async is *crucial*; if it is not done, this will fall into an
infinite loop of executions through this spot in subshell after
subshell until the process limit is exhausted. */
if (asynchronous)
{
command->flags |= CMD_FORCE_SUBSHELL;
exec_result =
execute_command_internal (command, 1, pipe_in, pipe_out,
fds_to_close);
}
else
{
if (ignore_return && command->value.Group->command)
command->value.Group->command->flags |= CMD_IGNORE_RETURN;
exec_result =
execute_command_internal (command->value.Group->command,
asynchronous, pipe_in, pipe_out,
fds_to_close);
}
break;
case cm_connection:
exec_result = execute_connection (command, asynchronous,
pipe_in, pipe_out, fds_to_close);
break;
#if defined (DPAREN_ARITHMETIC)
case cm_arith:
if (ignore_return)
command->value.Arith->flags |= CMD_IGNORE_RETURN;
exec_result = execute_arith_command (command->value.Arith);
break;
#endif
#if defined (COND_COMMAND)
case cm_cond:
if (ignore_return)
command->value.Cond->flags |= CMD_IGNORE_RETURN;
save_line_number = line_number;
exec_result = execute_cond_command (command->value.Cond);
line_number = save_line_number;
break;
#endif
case cm_function_def:
exec_result = execute_intern_function (command->value.Function_def->name,
command->value.Function_def->command);
break;
default:
command_error ("execute_command", CMDERR_BADTYPE, command->type, 0);
}
if (my_undo_list)
{
do_redirections (my_undo_list, RX_ACTIVE);
dispose_redirects (my_undo_list);
}
if (exec_undo_list)
dispose_redirects (exec_undo_list);
if (my_undo_list || exec_undo_list)
discard_unwind_frame ("loop_redirections");
/* Invert the return value if we have to */
if (invert)
exec_result = (exec_result == EXECUTION_SUCCESS)
? EXECUTION_FAILURE
: EXECUTION_SUCCESS;
#if defined (DPAREN_ARITHMETIC) || defined (COND_COMMAND)
/* This is where we set PIPESTATUS from the exit status of the appropriate
compound commands (the ones that look enough like simple commands to
cause confusion). We might be able to optimize by not doing this if
subshell_environment != 0. */
switch (command->type)
{
# if defined (DPAREN_ARITHMETIC)
case cm_arith:
# endif
# if defined (COND_COMMAND)
case cm_cond:
# endif
set_pipestatus_from_exit (exec_result);
break;
}
#endif
last_command_exit_value = exec_result;
run_pending_traps ();
#if 0
if (running_trap == 0)
#endif
currently_executing_command = (COMMAND *)NULL;
return (last_command_exit_value);
}
#if defined (COMMAND_TIMING)
#if defined (HAVE_GETRUSAGE) && defined (HAVE_GETTIMEOFDAY)
extern struct timeval *difftimeval __P((struct timeval *, struct timeval *, struct timeval *));
extern struct timeval *addtimeval __P((struct timeval *, struct timeval *, struct timeval *));
extern int timeval_to_cpu __P((struct timeval *, struct timeval *, struct timeval *));
#endif
#define POSIX_TIMEFORMAT "real %2R\nuser %2U\nsys %2S"
#define BASH_TIMEFORMAT "\nreal\t%3lR\nuser\t%3lU\nsys\t%3lS"
static int precs[] = { 0, 100, 10, 1 };
/* Expand one `%'-prefixed escape sequence from a time format string. */
static int
mkfmt (buf, prec, lng, sec, sec_fraction)
char *buf;
int prec, lng;
time_t sec;
int sec_fraction;
{
time_t min;
char abuf[INT_STRLEN_BOUND(time_t) + 1];
int ind, aind;
ind = 0;
abuf[sizeof(abuf) - 1] = '\0';
/* If LNG is non-zero, we want to decompose SEC into minutes and seconds. */
if (lng)
{
min = sec / 60;
sec %= 60;
aind = sizeof(abuf) - 2;
do
abuf[aind--] = (min % 10) + '0';
while (min /= 10);
aind++;
while (abuf[aind])
buf[ind++] = abuf[aind++];
buf[ind++] = 'm';
}
/* Now add the seconds. */
aind = sizeof (abuf) - 2;
do
abuf[aind--] = (sec % 10) + '0';
while (sec /= 10);
aind++;
while (abuf[aind])
buf[ind++] = abuf[aind++];
/* We want to add a decimal point and PREC places after it if PREC is
nonzero. PREC is not greater than 3. SEC_FRACTION is between 0
and 999. */
if (prec != 0)
{
buf[ind++] = '.';
for (aind = 1; aind <= prec; aind++)
{
buf[ind++] = (sec_fraction / precs[aind]) + '0';
sec_fraction %= precs[aind];
}
}
if (lng)
buf[ind++] = 's';
buf[ind] = '\0';
return (ind);
}
/* Interpret the format string FORMAT, interpolating the following escape
sequences:
%[prec][l][RUS]
where the optional `prec' is a precision, meaning the number of
characters after the decimal point, the optional `l' means to format
using minutes and seconds (MMmNN[.FF]s), like the `times' builtin',
and the last character is one of
R number of seconds of `real' time
U number of seconds of `user' time
S number of seconds of `system' time
An occurrence of `%%' in the format string is translated to a `%'. The
result is printed to FP, a pointer to a FILE. The other variables are
the seconds and thousandths of a second of real, user, and system time,
resectively. */
static void
print_formatted_time (fp, format, rs, rsf, us, usf, ss, ssf, cpu)
FILE *fp;
char *format;
time_t rs;
int rsf;
time_t us;
int usf;
time_t ss;
int ssf, cpu;
{
int prec, lng, len;
char *str, *s, ts[INT_STRLEN_BOUND (time_t) + sizeof ("mSS.FFFF")];
time_t sum;
int sum_frac;
int sindex, ssize;
len = strlen (format);
ssize = (len + 64) - (len % 64);
str = (char *)xmalloc (ssize);
sindex = 0;
for (s = format; *s; s++)
{
if (*s != '%' || s[1] == '\0')
{
RESIZE_MALLOCED_BUFFER (str, sindex, 1, ssize, 64);
str[sindex++] = *s;
}
else if (s[1] == '%')
{
s++;
RESIZE_MALLOCED_BUFFER (str, sindex, 1, ssize, 64);
str[sindex++] = *s;
}
else if (s[1] == 'P')
{
s++;
if (cpu > 10000)
cpu = 10000;
sum = cpu / 100;
sum_frac = (cpu % 100) * 10;
len = mkfmt (ts, 2, 0, sum, sum_frac);
RESIZE_MALLOCED_BUFFER (str, sindex, len, ssize, 64);
strcpy (str + sindex, ts);
sindex += len;
}
else
{
prec = 3; /* default is three places past the decimal point. */
lng = 0; /* default is to not use minutes or append `s' */
s++;
if (DIGIT (*s)) /* `precision' */
{
prec = *s++ - '0';
if (prec > 3) prec = 3;
}
if (*s == 'l') /* `length extender' */
{
lng = 1;
s++;
}
if (*s == 'R' || *s == 'E')
len = mkfmt (ts, prec, lng, rs, rsf);
else if (*s == 'U')
len = mkfmt (ts, prec, lng, us, usf);
else if (*s == 'S')
len = mkfmt (ts, prec, lng, ss, ssf);
else
{
internal_error (_("TIMEFORMAT: `%c': invalid format character"), *s);
free (str);
return;
}
RESIZE_MALLOCED_BUFFER (str, sindex, len, ssize, 64);
strcpy (str + sindex, ts);
sindex += len;
}
}
str[sindex] = '\0';
fprintf (fp, "%s\n", str);
fflush (fp);
free (str);
}
static int
time_command (command, asynchronous, pipe_in, pipe_out, fds_to_close)
COMMAND *command;
int asynchronous, pipe_in, pipe_out;
struct fd_bitmap *fds_to_close;
{
int rv, posix_time, old_flags;
time_t rs, us, ss;
int rsf, usf, ssf;
int cpu;
char *time_format;
#if defined (HAVE_GETRUSAGE) && defined (HAVE_GETTIMEOFDAY)
struct timeval real, user, sys;
struct timeval before, after;
# if defined (HAVE_STRUCT_TIMEZONE)
struct timezone dtz; /* posix doesn't define this */
# endif
struct rusage selfb, selfa, kidsb, kidsa; /* a = after, b = before */
#else
# if defined (HAVE_TIMES)
clock_t tbefore, tafter, real, user, sys;
struct tms before, after;
# endif
#endif
#if defined (HAVE_GETRUSAGE) && defined (HAVE_GETTIMEOFDAY)
# if defined (HAVE_STRUCT_TIMEZONE)
gettimeofday (&before, &dtz);
# else
gettimeofday (&before, (void *)NULL);
# endif /* !HAVE_STRUCT_TIMEZONE */
getrusage (RUSAGE_SELF, &selfb);
getrusage (RUSAGE_CHILDREN, &kidsb);
#else
# if defined (HAVE_TIMES)
tbefore = times (&before);
# endif
#endif
posix_time = (command->flags & CMD_TIME_POSIX);
old_flags = command->flags;
command->flags &= ~(CMD_TIME_PIPELINE|CMD_TIME_POSIX);
rv = execute_command_internal (command, asynchronous, pipe_in, pipe_out, fds_to_close);
command->flags = old_flags;
rs = us = ss = 0;
rsf = usf = ssf = cpu = 0;
#if defined (HAVE_GETRUSAGE) && defined (HAVE_GETTIMEOFDAY)
# if defined (HAVE_STRUCT_TIMEZONE)
gettimeofday (&after, &dtz);
# else
gettimeofday (&after, (void *)NULL);
# endif /* !HAVE_STRUCT_TIMEZONE */
getrusage (RUSAGE_SELF, &selfa);
getrusage (RUSAGE_CHILDREN, &kidsa);
difftimeval (&real, &before, &after);
timeval_to_secs (&real, &rs, &rsf);
addtimeval (&user, difftimeval(&after, &selfb.ru_utime, &selfa.ru_utime),
difftimeval(&before, &kidsb.ru_utime, &kidsa.ru_utime));
timeval_to_secs (&user, &us, &usf);
addtimeval (&sys, difftimeval(&after, &selfb.ru_stime, &selfa.ru_stime),
difftimeval(&before, &kidsb.ru_stime, &kidsa.ru_stime));
timeval_to_secs (&sys, &ss, &ssf);
cpu = timeval_to_cpu (&real, &user, &sys);
#else
# if defined (HAVE_TIMES)
tafter = times (&after);
real = tafter - tbefore;
clock_t_to_secs (real, &rs, &rsf);
user = (after.tms_utime - before.tms_utime) + (after.tms_cutime - before.tms_cutime);
clock_t_to_secs (user, &us, &usf);
sys = (after.tms_stime - before.tms_stime) + (after.tms_cstime - before.tms_cstime);
clock_t_to_secs (sys, &ss, &ssf);
cpu = (real == 0) ? 0 : ((user + sys) * 10000) / real;
# else
rs = us = ss = 0;
rsf = usf = ssf = cpu = 0;
# endif
#endif
if (posix_time)
time_format = POSIX_TIMEFORMAT;
else if ((time_format = get_string_value ("TIMEFORMAT")) == 0)
time_format = BASH_TIMEFORMAT;
if (time_format && *time_format)
print_formatted_time (stderr, time_format, rs, rsf, us, usf, ss, ssf, cpu);
return rv;
}
#endif /* COMMAND_TIMING */
/* Execute a command that's supposed to be in a subshell. This must be
called after make_child and we must be running in the child process.
The caller will return or exit() immediately with the value this returns. */
static int
execute_in_subshell (command, asynchronous, pipe_in, pipe_out, fds_to_close)
COMMAND *command;
int asynchronous;
int pipe_in, pipe_out;
struct fd_bitmap *fds_to_close;
{
int user_subshell, return_code, function_value, should_redir_stdin, invert;
int ois;
COMMAND *tcom;
USE_VAR(user_subshell);
USE_VAR(invert);
USE_VAR(tcom);
USE_VAR(asynchronous);
subshell_level++;
should_redir_stdin = (asynchronous && (command->flags & CMD_STDIN_REDIR) &&
pipe_in == NO_PIPE &&
stdin_redirects (command->redirects) == 0);
invert = (command->flags & CMD_INVERT_RETURN) != 0;
user_subshell = command->type == cm_subshell || ((command->flags & CMD_WANT_SUBSHELL) != 0);
command->flags &= ~(CMD_FORCE_SUBSHELL | CMD_WANT_SUBSHELL | CMD_INVERT_RETURN);
/* If a command is asynchronous in a subshell (like ( foo ) & or
the special case of an asynchronous GROUP command where the
the subshell bit is turned on down in case cm_group: below),
turn off `asynchronous', so that two subshells aren't spawned.
XXX - asynchronous used to be set to 0 in this block, but that
means that setup_async_signals was never run. Now it's set to
0 after subshell_environment is set appropriately and setup_async_signals
is run.
This seems semantically correct to me. For example,
( foo ) & seems to say ``do the command `foo' in a subshell
environment, but don't wait for that subshell to finish'',
and "{ foo ; bar ; } &" seems to me to be like functions or
builtins in the background, which executed in a subshell
environment. I just don't see the need to fork two subshells. */
/* Don't fork again, we are already in a subshell. A `doubly
async' shell is not interactive, however. */
if (asynchronous)
{
#if defined (JOB_CONTROL)
/* If a construct like ( exec xxx yyy ) & is given while job
control is active, we want to prevent exec from putting the
subshell back into the original process group, carefully
undoing all the work we just did in make_child. */
original_pgrp = -1;
#endif /* JOB_CONTROL */
ois = interactive_shell;
interactive_shell = 0;
/* This test is to prevent alias expansion by interactive shells that
run `(command) &' but to allow scripts that have enabled alias
expansion with `shopt -s expand_alias' to continue to expand
aliases. */
if (ois != interactive_shell)
expand_aliases = 0;
}
/* Subshells are neither login nor interactive. */
login_shell = interactive = 0;
if (user_subshell)
subshell_environment = SUBSHELL_PAREN;
else
{
subshell_environment = 0; /* XXX */
if (asynchronous)
subshell_environment |= SUBSHELL_ASYNC;
if (pipe_in != NO_PIPE || pipe_out != NO_PIPE)
subshell_environment |= SUBSHELL_PIPE;
}
reset_terminating_signals (); /* in sig.c */
/* Cancel traps, in trap.c. */
restore_original_signals ();
/* Make sure restore_original_signals doesn't undo the work done by
make_child to ensure that asynchronous children are immune to SIGINT
and SIGQUIT. Turn off asynchronous to make sure more subshells are
not spawned. */
if (asynchronous)
{
setup_async_signals ();
asynchronous = 0;
}
#if defined (JOB_CONTROL)
set_sigchld_handler ();
#endif /* JOB_CONTROL */
set_sigint_handler ();
#if defined (JOB_CONTROL)
/* Delete all traces that there were any jobs running. This is
only for subshells. */
without_job_control ();
#endif /* JOB_CONTROL */
if (fds_to_close)
close_fd_bitmap (fds_to_close);
do_piping (pipe_in, pipe_out);
/* If this is a user subshell, set a flag if stdin was redirected.
This is used later to decide whether to redirect fd 0 to
/dev/null for async commands in the subshell. This adds more
sh compatibility, but I'm not sure it's the right thing to do. */
if (user_subshell)
{
stdin_redir = stdin_redirects (command->redirects);
restore_default_signal (0);
}
/* If this is an asynchronous command (command &), we want to
redirect the standard input from /dev/null in the absence of
any specific redirection involving stdin. */
if (should_redir_stdin && stdin_redir == 0)
async_redirect_stdin ();
/* Do redirections, then dispose of them before recursive call. */
if (command->redirects)
{
if (do_redirections (command->redirects, RX_ACTIVE) != 0)
exit (invert ? EXECUTION_SUCCESS : EXECUTION_FAILURE);
dispose_redirects (command->redirects);
command->redirects = (REDIRECT *)NULL;
}
tcom = (command->type == cm_subshell) ? command->value.Subshell->command : command;
if (command->flags & CMD_TIME_PIPELINE)
tcom->flags |= CMD_TIME_PIPELINE;
if (command->flags & CMD_TIME_POSIX)
tcom->flags |= CMD_TIME_POSIX;
/* Make sure the subshell inherits any CMD_IGNORE_RETURN flag. */
if ((command->flags & CMD_IGNORE_RETURN) && tcom != command)
tcom->flags |= CMD_IGNORE_RETURN;
/* If this is a simple command, tell execute_disk_command that it
might be able to get away without forking and simply exec.
This means things like ( sleep 10 ) will only cause one fork.
If we're timing the command or inverting its return value, however,
we cannot do this optimization. */
if (user_subshell && (tcom->type == cm_simple || tcom->type == cm_subshell) &&
((tcom->flags & CMD_TIME_PIPELINE) == 0) &&
((tcom->flags & CMD_INVERT_RETURN) == 0))
{
tcom->flags |= CMD_NO_FORK;
if (tcom->type == cm_simple)
tcom->value.Simple->flags |= CMD_NO_FORK;
}
invert = (tcom->flags & CMD_INVERT_RETURN) != 0;
tcom->flags &= ~CMD_INVERT_RETURN;
/* If we're inside a function while executing this subshell, we
need to handle a possible `return'. */
function_value = 0;
if (return_catch_flag)
function_value = setjmp (return_catch);
if (function_value)
return_code = return_catch_value;
else
return_code = execute_command_internal (tcom, asynchronous, NO_PIPE, NO_PIPE, fds_to_close);
/* If we are asked to, invert the return value. */
if (invert)
return_code = (return_code == EXECUTION_SUCCESS) ? EXECUTION_FAILURE
: EXECUTION_SUCCESS;
/* If we were explicitly placed in a subshell with (), we need
to do the `shell cleanup' things, such as running traps[0]. */
if (user_subshell && signal_is_trapped (0))
{
last_command_exit_value = return_code;
return_code = run_exit_trap ();
}
subshell_level--;
return (return_code);
/* NOTREACHED */
}
static int
execute_pipeline (command, asynchronous, pipe_in, pipe_out, fds_to_close)
COMMAND *command;
int asynchronous, pipe_in, pipe_out;
struct fd_bitmap *fds_to_close;
{
int prev, fildes[2], new_bitmap_size, dummyfd, ignore_return, exec_result;
COMMAND *cmd;
struct fd_bitmap *fd_bitmap;
#if defined (JOB_CONTROL)
sigset_t set, oset;
BLOCK_CHILD (set, oset);
#endif /* JOB_CONTROL */
ignore_return = (command->flags & CMD_IGNORE_RETURN) != 0;
prev = pipe_in;
cmd = command;
while (cmd && cmd->type == cm_connection &&
cmd->value.Connection && cmd->value.Connection->connector == '|')
{
/* Make a pipeline between the two commands. */
if (pipe (fildes) < 0)
{
sys_error ("pipe error");
#if defined (JOB_CONTROL)
terminate_current_pipeline ();
kill_current_pipeline ();
UNBLOCK_CHILD (oset);
#endif /* JOB_CONTROL */
last_command_exit_value = EXECUTION_FAILURE;
/* The unwind-protects installed below will take care
of closing all of the open file descriptors. */
throw_to_top_level ();
return (EXECUTION_FAILURE); /* XXX */
}
/* Here is a problem: with the new file close-on-exec
code, the read end of the pipe (fildes[0]) stays open
in the first process, so that process will never get a
SIGPIPE. There is no way to signal the first process
that it should close fildes[0] after forking, so it
remains open. No SIGPIPE is ever sent because there
is still a file descriptor open for reading connected
to the pipe. We take care of that here. This passes
around a bitmap of file descriptors that must be
closed after making a child process in execute_simple_command. */
/* We need fd_bitmap to be at least as big as fildes[0].
If fildes[0] is less than fds_to_close->size, then
use fds_to_close->size. */
new_bitmap_size = (fildes[0] < fds_to_close->size)
? fds_to_close->size
: fildes[0] + 8;
fd_bitmap = new_fd_bitmap (new_bitmap_size);
/* Now copy the old information into the new bitmap. */
xbcopy ((char *)fds_to_close->bitmap, (char *)fd_bitmap->bitmap, fds_to_close->size);
/* And mark the pipe file descriptors to be closed. */
fd_bitmap->bitmap[fildes[0]] = 1;
/* In case there are pipe or out-of-processes errors, we
want all these file descriptors to be closed when
unwind-protects are run, and the storage used for the
bitmaps freed up. */
begin_unwind_frame ("pipe-file-descriptors");
add_unwind_protect (dispose_fd_bitmap, fd_bitmap);
add_unwind_protect (close_fd_bitmap, fd_bitmap);
if (prev >= 0)
add_unwind_protect (close, prev);
dummyfd = fildes[1];
add_unwind_protect (close, dummyfd);
#if defined (JOB_CONTROL)
add_unwind_protect (restore_signal_mask, &oset);
#endif /* JOB_CONTROL */
if (ignore_return && cmd->value.Connection->first)
cmd->value.Connection->first->flags |= CMD_IGNORE_RETURN;
execute_command_internal (cmd->value.Connection->first, asynchronous,
prev, fildes[1], fd_bitmap);
if (prev >= 0)
close (prev);
prev = fildes[0];
close (fildes[1]);
dispose_fd_bitmap (fd_bitmap);
discard_unwind_frame ("pipe-file-descriptors");
cmd = cmd->value.Connection->second;
}
/* Now execute the rightmost command in the pipeline. */
if (ignore_return && cmd)
cmd->flags |= CMD_IGNORE_RETURN;
exec_result = execute_command_internal (cmd, asynchronous, prev, pipe_out, fds_to_close);
if (prev >= 0)
close (prev);
#if defined (JOB_CONTROL)
UNBLOCK_CHILD (oset);
#endif
return (exec_result);
}
static int
execute_connection (command, asynchronous, pipe_in, pipe_out, fds_to_close)
COMMAND *command;
int asynchronous, pipe_in, pipe_out;
struct fd_bitmap *fds_to_close;
{
REDIRECT *rp;
COMMAND *tc, *second;
int ignore_return, exec_result;
ignore_return = (command->flags & CMD_IGNORE_RETURN) != 0;
switch (command->value.Connection->connector)
{
/* Do the first command asynchronously. */
case '&':
tc = command->value.Connection->first;
if (tc == 0)
return (EXECUTION_SUCCESS);
rp = tc->redirects;
if (ignore_return)
tc->flags |= CMD_IGNORE_RETURN;
tc->flags |= CMD_AMPERSAND;
/* If this shell was compiled without job control support,
if we are currently in a subshell via `( xxx )', or if job
control is not active then the standard input for an
asynchronous command is forced to /dev/null. */
#if defined (JOB_CONTROL)
if ((subshell_environment || !job_control) && !stdin_redir)
#else
if (!stdin_redir)
#endif /* JOB_CONTROL */
tc->flags |= CMD_STDIN_REDIR;
exec_result = execute_command_internal (tc, 1, pipe_in, pipe_out, fds_to_close);
if (tc->flags & CMD_STDIN_REDIR)
tc->flags &= ~CMD_STDIN_REDIR;
second = command->value.Connection->second;
if (second)
{
if (ignore_return)
second->flags |= CMD_IGNORE_RETURN;
exec_result = execute_command_internal (second, asynchronous, pipe_in, pipe_out, fds_to_close);
}
break;
/* Just call execute command on both sides. */
case ';':
if (ignore_return)
{
if (command->value.Connection->first)
command->value.Connection->first->flags |= CMD_IGNORE_RETURN;
if (command->value.Connection->second)
command->value.Connection->second->flags |= CMD_IGNORE_RETURN;
}
QUIT;
execute_command (command->value.Connection->first);
QUIT;
exec_result = execute_command_internal (command->value.Connection->second,
asynchronous, pipe_in, pipe_out,
fds_to_close);
break;
case '|':
exec_result = execute_pipeline (command, asynchronous, pipe_in, pipe_out, fds_to_close);
break;
case AND_AND:
case OR_OR:
if (asynchronous)
{
/* If we have something like `a && b &' or `a || b &', run the
&& or || stuff in a subshell. Force a subshell and just call
execute_command_internal again. Leave asynchronous on
so that we get a report from the parent shell about the
background job. */
command->flags |= CMD_FORCE_SUBSHELL;
exec_result = execute_command_internal (command, 1, pipe_in, pipe_out, fds_to_close);
break;
}
/* Execute the first command. If the result of that is successful
and the connector is AND_AND, or the result is not successful
and the connector is OR_OR, then execute the second command,
otherwise return. */
if (command->value.Connection->first)
command->value.Connection->first->flags |= CMD_IGNORE_RETURN;
exec_result = execute_command (command->value.Connection->first);
QUIT;
if (((command->value.Connection->connector == AND_AND) &&
(exec_result == EXECUTION_SUCCESS)) ||
((command->value.Connection->connector == OR_OR) &&
(exec_result != EXECUTION_SUCCESS)))
{
if (ignore_return && command->value.Connection->second)
command->value.Connection->second->flags |= CMD_IGNORE_RETURN;
exec_result = execute_command (command->value.Connection->second);
}
break;
default:
command_error ("execute_connection", CMDERR_BADCONN, command->value.Connection->connector, 0);
jump_to_top_level (DISCARD);
exec_result = EXECUTION_FAILURE;
}
return exec_result;
}
#define REAP() \
do \
{ \
if (!interactive_shell) \
reap_dead_jobs (); \
} \
while (0)
/* Execute a FOR command. The syntax is: FOR word_desc IN word_list;
DO command; DONE */
static int
execute_for_command (for_command)
FOR_COM *for_command;
{
register WORD_LIST *releaser, *list;
SHELL_VAR *v;
char *identifier;
int retval, save_line_number;
#if 0
SHELL_VAR *old_value = (SHELL_VAR *)NULL; /* Remember the old value of x. */
#endif
save_line_number = line_number;
if (check_identifier (for_command->name, 1) == 0)
{
if (posixly_correct && interactive_shell == 0)
{
last_command_exit_value = EX_USAGE;
jump_to_top_level (ERREXIT);
}
return (EXECUTION_FAILURE);
}
loop_level++;
identifier = for_command->name->word;
list = releaser = expand_words_no_vars (for_command->map_list);
begin_unwind_frame ("for");
add_unwind_protect (dispose_words, releaser);
#if 0
if (lexical_scoping)
{
old_value = copy_variable (find_variable (identifier));
if (old_value)
add_unwind_protect (dispose_variable, old_value);
}
#endif
if (for_command->flags & CMD_IGNORE_RETURN)
for_command->action->flags |= CMD_IGNORE_RETURN;
for (retval = EXECUTION_SUCCESS; list; list = list->next)
{
QUIT;
line_number = for_command->line;
/* Remember what this command looks like, for debugger. */
command_string_index = 0;
print_for_command_head (for_command);
if (echo_command_at_execute)
xtrace_print_for_command_head (for_command);
/* Save this command unless it's a trap command and we're not running
a debug trap. */
#if 0
if (signal_in_progress (DEBUG_TRAP) == 0 && (this_command_name == 0 || (STREQ (this_command_name, "trap") == 0)))
#else
if (signal_in_progress (DEBUG_TRAP) == 0 && running_trap == 0)
#endif
{
FREE (the_printed_command_except_trap);
the_printed_command_except_trap = savestring (the_printed_command);
}
retval = run_debug_trap ();
#if defined (DEBUGGER)
/* In debugging mode, if the DEBUG trap returns a non-zero status, we
skip the command. */
if (debugging_mode && retval != EXECUTION_SUCCESS)
continue;
#endif
this_command_name = (char *)NULL;
v = bind_variable (identifier, list->word->word, 0);
if (readonly_p (v) || noassign_p (v))
{
line_number = save_line_number;
if (readonly_p (v) && interactive_shell == 0 && posixly_correct)
{
last_command_exit_value = EXECUTION_FAILURE;
jump_to_top_level (FORCE_EOF);
}
else
{
dispose_words (releaser);
discard_unwind_frame ("for");
loop_level--;
return (EXECUTION_FAILURE);
}
}
retval = execute_command (for_command->action);
REAP ();
QUIT;
if (breaking)
{
breaking--;
break;
}
if (continuing)
{
continuing--;
if (continuing)
break;
}
}
loop_level--;
line_number = save_line_number;
#if 0
if (lexical_scoping)
{
if (!old_value)
unbind_variable (identifier);
else
{
SHELL_VAR *new_value;
new_value = bind_variable (identifier, value_cell(old_value), 0);
new_value->attributes = old_value->attributes;
dispose_variable (old_value);
}
}
#endif
dispose_words (releaser);
discard_unwind_frame ("for");
return (retval);
}
#if defined (ARITH_FOR_COMMAND)
/* Execute an arithmetic for command. The syntax is
for (( init ; step ; test ))
do
body
done
The execution should be exactly equivalent to
eval \(\( init \)\)
while eval \(\( test \)\) ; do
body;
eval \(\( step \)\)
done
*/
static intmax_t
eval_arith_for_expr (l, okp)
WORD_LIST *l;
int *okp;
{
WORD_LIST *new;
intmax_t expresult;
int r;
new = expand_words_no_vars (l);
if (new)
{
if (echo_command_at_execute)
xtrace_print_arith_cmd (new);
this_command_name = "(("; /* )) for expression error messages */
command_string_index = 0;
print_arith_command (new);
if (signal_in_progress (DEBUG_TRAP) == 0)
{
FREE (the_printed_command_except_trap);
the_printed_command_except_trap = savestring (the_printed_command);
}
r = run_debug_trap ();
/* In debugging mode, if the DEBUG trap returns a non-zero status, we
skip the command. */
#if defined (DEBUGGER)
if (debugging_mode == 0 || r == EXECUTION_SUCCESS)
expresult = evalexp (new->word->word, okp);
else
{
expresult = 0;
if (okp)
*okp = 1;
}
#else
expresult = evalexp (new->word->word, okp);
#endif
dispose_words (new);
}
else
{
expresult = 0;
if (okp)
*okp = 1;
}
return (expresult);
}
static int
execute_arith_for_command (arith_for_command)
ARITH_FOR_COM *arith_for_command;
{
intmax_t expresult;
int expok, body_status, arith_lineno, save_lineno;
body_status = EXECUTION_SUCCESS;
loop_level++;
save_lineno = line_number;
if (arith_for_command->flags & CMD_IGNORE_RETURN)
arith_for_command->action->flags |= CMD_IGNORE_RETURN;
this_command_name = "(("; /* )) for expression error messages */
/* save the starting line number of the command so we can reset
line_number before executing each expression -- for $LINENO
and the DEBUG trap. */
line_number = arith_lineno = arith_for_command->line;
if (variable_context && interactive_shell)
line_number -= function_line_number;
/* Evaluate the initialization expression. */
expresult = eval_arith_for_expr (arith_for_command->init, &expok);
if (expok == 0)
{
line_number = save_lineno;
return (EXECUTION_FAILURE);
}
while (1)
{
/* Evaluate the test expression. */
line_number = arith_lineno;
expresult = eval_arith_for_expr (arith_for_command->test, &expok);
line_number = save_lineno;
if (expok == 0)
{
body_status = EXECUTION_FAILURE;
break;
}
REAP ();
if (expresult == 0)
break;
/* Execute the body of the arithmetic for command. */
QUIT;
body_status = execute_command (arith_for_command->action);
QUIT;
/* Handle any `break' or `continue' commands executed by the body. */
if (breaking)
{
breaking--;
break;
}
if (continuing)
{
continuing--;
if (continuing)
break;
}
/* Evaluate the step expression. */
line_number = arith_lineno;
expresult = eval_arith_for_expr (arith_for_command->step, &expok);
line_number = save_lineno;
if (expok == 0)
{
body_status = EXECUTION_FAILURE;
break;
}
}
loop_level--;
line_number = save_lineno;
return (body_status);
}
#endif
#if defined (SELECT_COMMAND)
static int LINES, COLS, tabsize;
#define RP_SPACE ") "
#define RP_SPACE_LEN 2
/* XXX - does not handle numbers > 1000000 at all. */
#define NUMBER_LEN(s) \
((s < 10) ? 1 \
: ((s < 100) ? 2 \
: ((s < 1000) ? 3 \
: ((s < 10000) ? 4 \
: ((s < 100000) ? 5 \
: 6)))))
static int
print_index_and_element (len, ind, list)
int len, ind;
WORD_LIST *list;
{
register WORD_LIST *l;
register int i;
if (list == 0)
return (0);
for (i = ind, l = list; l && --i; l = l->next)
;
fprintf (stderr, "%*d%s%s", len, ind, RP_SPACE, l->word->word);
return (STRLEN (l->word->word));
}
static void
indent (from, to)
int from, to;
{
while (from < to)
{
if ((to / tabsize) > (from / tabsize))
{
putc ('\t', stderr);
from += tabsize - from % tabsize;
}
else
{
putc (' ', stderr);
from++;
}
}
}
static void
print_select_list (list, list_len, max_elem_len, indices_len)
WORD_LIST *list;
int list_len, max_elem_len, indices_len;
{
int ind, row, elem_len, pos, cols, rows;
int first_column_indices_len, other_indices_len;
if (list == 0)
{
putc ('\n', stderr);
return;
}
cols = max_elem_len ? COLS / max_elem_len : 1;
if (cols == 0)
cols = 1;
rows = list_len ? list_len / cols + (list_len % cols != 0) : 1;
cols = list_len ? list_len / rows + (list_len % rows != 0) : 1;
if (rows == 1)
{
rows = cols;
cols = 1;
}
first_column_indices_len = NUMBER_LEN (rows);
other_indices_len = indices_len;
for (row = 0; row < rows; row++)
{
ind = row;
pos = 0;
while (1)
{
indices_len = (pos == 0) ? first_column_indices_len : other_indices_len;
elem_len = print_index_and_element (indices_len, ind + 1, list);
elem_len += indices_len + RP_SPACE_LEN;
ind += rows;
if (ind >= list_len)
break;
indent (pos + elem_len, pos + max_elem_len);
pos += max_elem_len;
}
putc ('\n', stderr);
}
}
/* Print the elements of LIST, one per line, preceded by an index from 1 to
LIST_LEN. Then display PROMPT and wait for the user to enter a number.
If the number is between 1 and LIST_LEN, return that selection. If EOF
is read, return a null string. If a blank line is entered, or an invalid
number is entered, the loop is executed again. */
static char *
select_query (list, list_len, prompt, print_menu)
WORD_LIST *list;
int list_len;
char *prompt;
int print_menu;
{
int max_elem_len, indices_len, len;
intmax_t reply;
WORD_LIST *l;
char *repl_string, *t;
t = get_string_value ("LINES");
LINES = (t && *t) ? atoi (t) : 24;
t = get_string_value ("COLUMNS");
COLS = (t && *t) ? atoi (t) : 80;
#if 0
t = get_string_value ("TABSIZE");
tabsize = (t && *t) ? atoi (t) : 8;
if (tabsize <= 0)
tabsize = 8;
#else
tabsize = 8;
#endif
max_elem_len = 0;
for (l = list; l; l = l->next)
{
len = STRLEN (l->word->word);
if (len > max_elem_len)
max_elem_len = len;
}
indices_len = NUMBER_LEN (list_len);
max_elem_len += indices_len + RP_SPACE_LEN + 2;
while (1)
{
if (print_menu)
print_select_list (list, list_len, max_elem_len, indices_len);
fprintf (stderr, "%s", prompt);
fflush (stderr);
QUIT;
if (read_builtin ((WORD_LIST *)NULL) == EXECUTION_FAILURE)
{
putchar ('\n');
return ((char *)NULL);
}
repl_string = get_string_value ("REPLY");
if (*repl_string == 0)
{
print_menu = 1;
continue;
}
if (legal_number (repl_string, &reply) == 0)
return "";
if (reply < 1 || reply > list_len)
return "";
for (l = list; l && --reply; l = l->next)
;
return (l->word->word);
}
}
/* Execute a SELECT command. The syntax is:
SELECT word IN list DO command_list DONE
Only `break' or `return' in command_list will terminate
the command. */
static int
execute_select_command (select_command)
SELECT_COM *select_command;
{
WORD_LIST *releaser, *list;
SHELL_VAR *v;
char *identifier, *ps3_prompt, *selection;
int retval, list_len, show_menu, save_line_number;
if (check_identifier (select_command->name, 1) == 0)
return (EXECUTION_FAILURE);
save_line_number = line_number;
line_number = select_command->line;
command_string_index = 0;
print_select_command_head (select_command);
if (echo_command_at_execute)
xtrace_print_select_command_head (select_command);
#if 0
if (signal_in_progress (DEBUG_TRAP) == 0 && (this_command_name == 0 || (STREQ (this_command_name, "trap") == 0)))
#else
if (signal_in_progress (DEBUG_TRAP) == 0 && running_trap == 0)
#endif
{
FREE (the_printed_command_except_trap);
the_printed_command_except_trap = savestring (the_printed_command);
}
retval = run_debug_trap ();
#if defined (DEBUGGER)
/* In debugging mode, if the DEBUG trap returns a non-zero status, we
skip the command. */
if (debugging_mode && retval != EXECUTION_SUCCESS)
return (EXECUTION_SUCCESS);
#endif
loop_level++;
identifier = select_command->name->word;
/* command and arithmetic substitution, parameter and variable expansion,
word splitting, pathname expansion, and quote removal. */
list = releaser = expand_words_no_vars (select_command->map_list);
list_len = list_length (list);
if (list == 0 || list_len == 0)
{
if (list)
dispose_words (list);
line_number = save_line_number;
return (EXECUTION_SUCCESS);
}
begin_unwind_frame ("select");
add_unwind_protect (dispose_words, releaser);
if (select_command->flags & CMD_IGNORE_RETURN)
select_command->action->flags |= CMD_IGNORE_RETURN;
retval = EXECUTION_SUCCESS;
show_menu = 1;
while (1)
{
line_number = select_command->line;
ps3_prompt = get_string_value ("PS3");
if (ps3_prompt == 0)
ps3_prompt = "#? ";
QUIT;
selection = select_query (list, list_len, ps3_prompt, show_menu);
QUIT;
if (selection == 0)
{
/* select_query returns EXECUTION_FAILURE if the read builtin
fails, so we want to return failure in this case. */
retval = EXECUTION_FAILURE;
break;
}
v = bind_variable (identifier, selection, 0);
if (readonly_p (v) || noassign_p (v))
{
if (readonly_p (v) && interactive_shell == 0 && posixly_correct)
{
last_command_exit_value = EXECUTION_FAILURE;
jump_to_top_level (FORCE_EOF);
}
else
{
dispose_words (releaser);
discard_unwind_frame ("select");
loop_level--;
line_number = save_line_number;
return (EXECUTION_FAILURE);
}
}
retval = execute_command (select_command->action);
REAP ();
QUIT;
if (breaking)
{
breaking--;
break;
}
if (continuing)
{
continuing--;
if (continuing)
break;
}
#if defined (KSH_COMPATIBLE_SELECT)
show_menu = 0;
selection = get_string_value ("REPLY");
if (selection && *selection == '\0')
show_menu = 1;
#endif
}
loop_level--;
line_number = save_line_number;
dispose_words (releaser);
discard_unwind_frame ("select");
return (retval);
}
#endif /* SELECT_COMMAND */
/* Execute a CASE command. The syntax is: CASE word_desc IN pattern_list ESAC.
The pattern_list is a linked list of pattern clauses; each clause contains
some patterns to compare word_desc against, and an associated command to
execute. */
static int
execute_case_command (case_command)
CASE_COM *case_command;
{
register WORD_LIST *list;
WORD_LIST *wlist, *es;
PATTERN_LIST *clauses;
char *word, *pattern;
int retval, match, ignore_return, save_line_number;
save_line_number = line_number;
line_number = case_command->line;
command_string_index = 0;
print_case_command_head (case_command);
if (echo_command_at_execute)
xtrace_print_case_command_head (case_command);
#if 0
if (signal_in_progress (DEBUG_TRAP) == 0 && (this_command_name == 0 || (STREQ (this_command_name, "trap") == 0)))
#else
if (signal_in_progress (DEBUG_TRAP) == 0 && running_trap == 0)
#endif
{
FREE (the_printed_command_except_trap);
the_printed_command_except_trap = savestring (the_printed_command);
}
retval = run_debug_trap();
#if defined (DEBUGGER)
/* In debugging mode, if the DEBUG trap returns a non-zero status, we
skip the command. */
if (debugging_mode && retval != EXECUTION_SUCCESS)
{
line_number = save_line_number;
return (EXECUTION_SUCCESS);
}
#endif
wlist = expand_word_unsplit (case_command->word, 0);
word = wlist ? string_list (wlist) : savestring ("");
dispose_words (wlist);
retval = EXECUTION_SUCCESS;
ignore_return = case_command->flags & CMD_IGNORE_RETURN;
begin_unwind_frame ("case");
add_unwind_protect ((Function *)xfree, word);
#define EXIT_CASE() goto exit_case_command
for (clauses = case_command->clauses; clauses; clauses = clauses->next)
{
QUIT;
for (list = clauses->patterns; list; list = list->next)
{
es = expand_word_leave_quoted (list->word, 0);
if (es && es->word && es->word->word && *(es->word->word))
pattern = quote_string_for_globbing (es->word->word, QGLOB_CVTNULL);
else
{
pattern = (char *)xmalloc (1);
pattern[0] = '\0';
}
/* Since the pattern does not undergo quote removal (as per
Posix.2, section 3.9.4.3), the strmatch () call must be able
to recognize backslashes as escape characters. */
match = strmatch (pattern, word, FNMATCH_EXTFLAG|FNMATCH_IGNCASE) != FNM_NOMATCH;
free (pattern);
dispose_words (es);
if (match)
{
if (clauses->action && ignore_return)
clauses->action->flags |= CMD_IGNORE_RETURN;
retval = execute_command (clauses->action);
EXIT_CASE ();
}
QUIT;
}
}
exit_case_command:
free (word);
discard_unwind_frame ("case");
line_number = save_line_number;
return (retval);
}
#define CMD_WHILE 0
#define CMD_UNTIL 1
/* The WHILE command. Syntax: WHILE test DO action; DONE.
Repeatedly execute action while executing test produces
EXECUTION_SUCCESS. */
static int
execute_while_command (while_command)
WHILE_COM *while_command;
{
return (execute_while_or_until (while_command, CMD_WHILE));
}
/* UNTIL is just like WHILE except that the test result is negated. */
static int
execute_until_command (while_command)
WHILE_COM *while_command;
{
return (execute_while_or_until (while_command, CMD_UNTIL));
}
/* The body for both while and until. The only difference between the
two is that the test value is treated differently. TYPE is
CMD_WHILE or CMD_UNTIL. The return value for both commands should
be EXECUTION_SUCCESS if no commands in the body are executed, and
the status of the last command executed in the body otherwise. */
static int
execute_while_or_until (while_command, type)
WHILE_COM *while_command;
int type;
{
int return_value, body_status;
body_status = EXECUTION_SUCCESS;
loop_level++;
while_command->test->flags |= CMD_IGNORE_RETURN;
if (while_command->flags & CMD_IGNORE_RETURN)
while_command->action->flags |= CMD_IGNORE_RETURN;
while (1)
{
return_value = execute_command (while_command->test);
REAP ();
/* Need to handle `break' in the test when we would break out of the
loop. The job control code will set `breaking' to loop_level
when a job in a loop is stopped with SIGTSTP. If the stopped job
is in the loop test, `breaking' will not be reset unless we do
this, and the shell will cease to execute commands. */
if (type == CMD_WHILE && return_value != EXECUTION_SUCCESS)
{
if (breaking)
breaking--;
break;
}
if (type == CMD_UNTIL && return_value == EXECUTION_SUCCESS)
{
if (breaking)
breaking--;
break;
}
QUIT;
body_status = execute_command (while_command->action);
QUIT;
if (breaking)
{
breaking--;
break;
}
if (continuing)
{
continuing--;
if (continuing)
break;
}
}
loop_level--;
return (body_status);
}
/* IF test THEN command [ELSE command].
IF also allows ELIF in the place of ELSE IF, but
the parser makes *that* stupidity transparent. */
static int
execute_if_command (if_command)
IF_COM *if_command;
{
int return_value, save_line_number;
save_line_number = line_number;
if_command->test->flags |= CMD_IGNORE_RETURN;
return_value = execute_command (if_command->test);
line_number = save_line_number;
if (return_value == EXECUTION_SUCCESS)
{
QUIT;
if (if_command->true_case && (if_command->flags & CMD_IGNORE_RETURN))
if_command->true_case->flags |= CMD_IGNORE_RETURN;
return (execute_command (if_command->true_case));
}
else
{
QUIT;
if (if_command->false_case && (if_command->flags & CMD_IGNORE_RETURN))
if_command->false_case->flags |= CMD_IGNORE_RETURN;
return (execute_command (if_command->false_case));
}
}
#if defined (DPAREN_ARITHMETIC)
static int
execute_arith_command (arith_command)
ARITH_COM *arith_command;
{
int expok, save_line_number, retval;
intmax_t expresult;
WORD_LIST *new;
char *exp;
expresult = 0;
save_line_number = line_number;
this_command_name = "(("; /* )) */
line_number = arith_command->line;
/* If we're in a function, update the line number information. */
if (variable_context && interactive_shell)
line_number -= function_line_number;
command_string_index = 0;
print_arith_command (arith_command->exp);
if (signal_in_progress (DEBUG_TRAP) == 0)
{
FREE (the_printed_command_except_trap);
the_printed_command_except_trap = savestring (the_printed_command);
}
/* Run the debug trap before each arithmetic command, but do it after we
update the line number information and before we expand the various
words in the expression. */
retval = run_debug_trap ();
#if defined (DEBUGGER)
/* In debugging mode, if the DEBUG trap returns a non-zero status, we
skip the command. */
if (debugging_mode && retval != EXECUTION_SUCCESS)
{
line_number = save_line_number;
return (EXECUTION_SUCCESS);
}
#endif
new = expand_words_no_vars (arith_command->exp);
/* If we're tracing, make a new word list with `((' at the front and `))'
at the back and print it. */
if (echo_command_at_execute)
xtrace_print_arith_cmd (new);
if (new)
{
exp = new->next ? string_list (new) : new->word->word;
expresult = evalexp (exp, &expok);
line_number = save_line_number;
if (exp != new->word->word)
free (exp);
dispose_words (new);
}
else
{
expresult = 0;
expok = 1;
}
if (expok == 0)
return (EXECUTION_FAILURE);
return (expresult == 0 ? EXECUTION_FAILURE : EXECUTION_SUCCESS);
}
#endif /* DPAREN_ARITHMETIC */
#if defined (COND_COMMAND)
static char *nullstr = "";
static int
execute_cond_node (cond)
COND_COM *cond;
{
int result, invert, patmatch, rmatch, mflags;
char *arg1, *arg2;
invert = (cond->flags & CMD_INVERT_RETURN);
if (cond->type == COND_EXPR)
result = execute_cond_node (cond->left);
else if (cond->type == COND_OR)
{
result = execute_cond_node (cond->left);
if (result != EXECUTION_SUCCESS)
result = execute_cond_node (cond->right);
}
else if (cond->type == COND_AND)
{
result = execute_cond_node (cond->left);
if (result == EXECUTION_SUCCESS)
result = execute_cond_node (cond->right);
}
else if (cond->type == COND_UNARY)
{
arg1 = cond_expand_word (cond->left->op, 0);
if (arg1 == 0)
arg1 = nullstr;
if (echo_command_at_execute)
xtrace_print_cond_term (cond->type, invert, cond->op, arg1, (char *)NULL);
result = unary_test (cond->op->word, arg1) ? EXECUTION_SUCCESS : EXECUTION_FAILURE;
if (arg1 != nullstr)
free (arg1);
}
else if (cond->type == COND_BINARY)
{
rmatch = 0;
patmatch = ((cond->op->word[1] == '=') && (cond->op->word[2] == '\0') &&
(cond->op->word[0] == '!' || cond->op->word[0] == '=') ||
(cond->op->word[0] == '=' && cond->op->word[1] == '\0'));
#if defined (COND_REGEXP)
rmatch = (cond->op->word[0] == '=' && cond->op->word[1] == '~' &&
cond->op->word[2] == '\0');
#endif
arg1 = cond_expand_word (cond->left->op, 0);
if (arg1 == 0)
arg1 = nullstr;
arg2 = cond_expand_word (cond->right->op,
(rmatch && shell_compatibility_level > 31) ? 2 : (patmatch ? 1 : 0));
if (arg2 == 0)
arg2 = nullstr;
if (echo_command_at_execute)
xtrace_print_cond_term (cond->type, invert, cond->op, arg1, arg2);
#if defined (COND_REGEXP)
if (rmatch)
{
mflags = SHMAT_PWARN;
#if defined (ARRAY_VARS)
mflags |= SHMAT_SUBEXP;
#endif
result = sh_regmatch (arg1, arg2, mflags);
}
else
#endif /* COND_REGEXP */
{
int oe;
oe = extended_glob;
extended_glob = 1;
result = binary_test (cond->op->word, arg1, arg2, TEST_PATMATCH|TEST_ARITHEXP)
? EXECUTION_SUCCESS
: EXECUTION_FAILURE;
extended_glob = oe;
}
if (arg1 != nullstr)
free (arg1);
if (arg2 != nullstr)
free (arg2);
}
else
{
command_error ("execute_cond_node", CMDERR_BADTYPE, cond->type, 0);
jump_to_top_level (DISCARD);
result = EXECUTION_FAILURE;
}
if (invert)
result = (result == EXECUTION_SUCCESS) ? EXECUTION_FAILURE : EXECUTION_SUCCESS;
return result;
}
static int
execute_cond_command (cond_command)
COND_COM *cond_command;
{
int retval, save_line_number;
retval = EXECUTION_SUCCESS;
save_line_number = line_number;
this_command_name = "[[";
line_number = cond_command->line;
/* If we're in a function, update the line number information. */
if (variable_context && interactive_shell)
line_number -= function_line_number;
command_string_index = 0;
print_cond_command (cond_command);
if (signal_in_progress (DEBUG_TRAP) == 0)
{
FREE (the_printed_command_except_trap);
the_printed_command_except_trap = savestring (the_printed_command);
}
/* Run the debug trap before each conditional command, but do it after we
update the line number information. */
retval = run_debug_trap ();
#if defined (DEBUGGER)
/* In debugging mode, if the DEBUG trap returns a non-zero status, we
skip the command. */
if (debugging_mode && retval != EXECUTION_SUCCESS)
{
line_number = save_line_number;
return (EXECUTION_SUCCESS);
}
#endif
#if 0
debug_print_cond_command (cond_command);
#endif
last_command_exit_value = retval = execute_cond_node (cond_command);
line_number = save_line_number;
return (retval);
}
#endif /* COND_COMMAND */
static void
bind_lastarg (arg)
char *arg;
{
SHELL_VAR *var;
if (arg == 0)
arg = "";
var = bind_variable ("_", arg, 0);
VUNSETATTR (var, att_exported);
}
/* Execute a null command. Fork a subshell if the command uses pipes or is
to be run asynchronously. This handles all the side effects that are
supposed to take place. */
static int
execute_null_command (redirects, pipe_in, pipe_out, async)
REDIRECT *redirects;
int pipe_in, pipe_out, async;
{
int r;
if (pipe_in != NO_PIPE || pipe_out != NO_PIPE || async)
{
/* We have a null command, but we really want a subshell to take
care of it. Just fork, do piping and redirections, and exit. */
if (make_child ((char *)NULL, async) == 0)
{
/* Cancel traps, in trap.c. */
restore_original_signals (); /* XXX */
do_piping (pipe_in, pipe_out);
if (async)
subshell_environment |= SUBSHELL_ASYNC;
if (pipe_in != NO_PIPE || pipe_out != NO_PIPE)
subshell_environment |= SUBSHELL_PIPE;
if (do_redirections (redirects, RX_ACTIVE) == 0)
exit (EXECUTION_SUCCESS);
else
exit (EXECUTION_FAILURE);
}
else
{
close_pipes (pipe_in, pipe_out);
#if defined (PROCESS_SUBSTITUTION) && defined (HAVE_DEV_FD)
unlink_fifo_list ();
#endif
return (EXECUTION_SUCCESS);
}
}
else
{
/* Even if there aren't any command names, pretend to do the
redirections that are specified. The user expects the side
effects to take place. If the redirections fail, then return
failure. Otherwise, if a command substitution took place while
expanding the command or a redirection, return the value of that
substitution. Otherwise, return EXECUTION_SUCCESS. */
r = do_redirections (redirects, RX_ACTIVE|RX_UNDOABLE);
cleanup_redirects (redirection_undo_list);
redirection_undo_list = (REDIRECT *)NULL;
if (r != 0)
return (EXECUTION_FAILURE);
else if (last_command_subst_pid != NO_PID)
return (last_command_exit_value);
else
return (EXECUTION_SUCCESS);
}
}
/* This is a hack to suppress word splitting for assignment statements
given as arguments to builtins with the ASSIGNMENT_BUILTIN flag set. */
static void
fix_assignment_words (words)
WORD_LIST *words;
{
WORD_LIST *w;
struct builtin *b;
if (words == 0)
return;
b = 0;
for (w = words; w; w = w->next)
if (w->word->flags & W_ASSIGNMENT)
{
if (b == 0)
{
b = builtin_address_internal (words->word->word, 0);
if (b == 0 || (b->flags & ASSIGNMENT_BUILTIN) == 0)
return;
else if (b && (b->flags & ASSIGNMENT_BUILTIN))
words->word->flags |= W_ASSNBLTIN;
}
w->word->flags |= (W_NOSPLIT|W_NOGLOB|W_TILDEEXP|W_ASSIGNARG);
}
}
/* The meaty part of all the executions. We have to start hacking the
real execution of commands here. Fork a process, set things up,
execute the command. */
static int
execute_simple_command (simple_command, pipe_in, pipe_out, async, fds_to_close)
SIMPLE_COM *simple_command;
int pipe_in, pipe_out, async;
struct fd_bitmap *fds_to_close;
{
WORD_LIST *words, *lastword;
char *command_line, *lastarg, *temp;
int first_word_quoted, result, builtin_is_special, already_forked, dofork;
pid_t old_last_async_pid;
sh_builtin_func_t *builtin;
SHELL_VAR *func;
result = EXECUTION_SUCCESS;
special_builtin_failed = builtin_is_special = 0;
command_line = (char *)0;
/* If we're in a function, update the line number information. */
if (variable_context && interactive_shell)
line_number -= function_line_number;
/* Remember what this command line looks like at invocation. */
command_string_index = 0;
print_simple_command (simple_command);
#if 0
if (signal_in_progress (DEBUG_TRAP) == 0 && (this_command_name == 0 || (STREQ (this_command_name, "trap") == 0)))
#else
if (signal_in_progress (DEBUG_TRAP) == 0 && running_trap == 0)
#endif
{
FREE (the_printed_command_except_trap);
the_printed_command_except_trap = the_printed_command ? savestring (the_printed_command) : (char *)0;
}
/* Run the debug trap before each simple command, but do it after we
update the line number information. */
result = run_debug_trap ();
#if defined (DEBUGGER)
/* In debugging mode, if the DEBUG trap returns a non-zero status, we
skip the command. */
if (debugging_mode && result != EXECUTION_SUCCESS)
return (EXECUTION_SUCCESS);
#endif
first_word_quoted =
simple_command->words ? (simple_command->words->word->flags & W_QUOTED): 0;
last_command_subst_pid = NO_PID;
old_last_async_pid = last_asynchronous_pid;
already_forked = dofork = 0;
/* If we're in a pipeline or run in the background, set DOFORK so we
make the child early, before word expansion. This keeps assignment
statements from affecting the parent shell's environment when they
should not. */
dofork = pipe_in != NO_PIPE || pipe_out != NO_PIPE || async;
/* Something like `%2 &' should restart job 2 in the background, not cause
the shell to fork here. */
if (dofork && pipe_in == NO_PIPE && pipe_out == NO_PIPE &&
simple_command->words && simple_command->words->word &&
simple_command->words->word->word &&
(simple_command->words->word->word[0] == '%'))
dofork = 0;
if (dofork)
{
/* Do this now, because execute_disk_command will do it anyway in the
vast majority of cases. */
maybe_make_export_env ();
/* Don't let a DEBUG trap overwrite the command string to be saved with
the process/job associated with this child. */
if (make_child (savestring (the_printed_command_except_trap), async) == 0)
{
already_forked = 1;
simple_command->flags |= CMD_NO_FORK;
subshell_environment = SUBSHELL_FORK;
if (pipe_in != NO_PIPE || pipe_out != NO_PIPE)
subshell_environment |= SUBSHELL_PIPE;
if (async)
subshell_environment |= SUBSHELL_ASYNC;
/* We need to do this before piping to handle some really
pathological cases where one of the pipe file descriptors
is < 2. */
if (fds_to_close)
close_fd_bitmap (fds_to_close);
do_piping (pipe_in, pipe_out);
pipe_in = pipe_out = NO_PIPE;
last_asynchronous_pid = old_last_async_pid;
}
else
{
close_pipes (pipe_in, pipe_out);
#if defined (PROCESS_SUBSTITUTION) && defined (HAVE_DEV_FD)
unlink_fifo_list ();
#endif
command_line = (char *)NULL; /* don't free this. */
bind_lastarg ((char *)NULL);
return (result);
}
}
/* If we are re-running this as the result of executing the `command'
builtin, do not expand the command words a second time. */
if ((simple_command->flags & CMD_INHIBIT_EXPANSION) == 0)
{
current_fds_to_close = fds_to_close;
fix_assignment_words (simple_command->words);
words = expand_words (simple_command->words);
current_fds_to_close = (struct fd_bitmap *)NULL;
}
else
words = copy_word_list (simple_command->words);
/* It is possible for WORDS not to have anything left in it.
Perhaps all the words consisted of `$foo', and there was
no variable `$foo'. */
if (words == 0)
{
this_command_name = 0;
result = execute_null_command (simple_command->redirects,
pipe_in, pipe_out,
already_forked ? 0 : async);
if (already_forked)
exit (result);
else
{
bind_lastarg ((char *)NULL);
set_pipestatus_from_exit (result);
return (result);
}
}
lastarg = (char *)NULL;
begin_unwind_frame ("simple-command");
if (echo_command_at_execute)
xtrace_print_word_list (words, 1);
builtin = (sh_builtin_func_t *)NULL;
func = (SHELL_VAR *)NULL;
if ((simple_command->flags & CMD_NO_FUNCTIONS) == 0)
{
/* Posix.2 says special builtins are found before functions. We
don't set builtin_is_special anywhere other than here, because
this path is followed only when the `command' builtin is *not*
being used, and we don't want to exit the shell if a special
builtin executed with `command builtin' fails. `command' is not
a special builtin. */
if (posixly_correct)
{
builtin = find_special_builtin (words->word->word);
if (builtin)
builtin_is_special = 1;
}
if (builtin == 0)
func = find_function (words->word->word);
}
/* In POSIX mode, assignment errors in the temporary environment cause a
non-interactive shell to exit. */
if (builtin_is_special && interactive_shell == 0 && tempenv_assign_error)
{
last_command_exit_value = EXECUTION_FAILURE;
jump_to_top_level (ERREXIT);
}
add_unwind_protect (dispose_words, words);
QUIT;
/* Bind the last word in this command to "$_" after execution. */
for (lastword = words; lastword->next; lastword = lastword->next)
;
lastarg = lastword->word->word;
#if defined (JOB_CONTROL)
/* Is this command a job control related thing? */
if (words->word->word[0] == '%' && already_forked == 0)
{
this_command_name = async ? "bg" : "fg";
last_shell_builtin = this_shell_builtin;
this_shell_builtin = builtin_address (this_command_name);
result = (*this_shell_builtin) (words);
goto return_result;
}
/* One other possiblilty. The user may want to resume an existing job.
If they do, find out whether this word is a candidate for a running
job. */
if (job_control && already_forked == 0 && async == 0 &&
!first_word_quoted &&
!words->next &&
words->word->word[0] &&
!simple_command->redirects &&
pipe_in == NO_PIPE &&
pipe_out == NO_PIPE &&
(temp = get_string_value ("auto_resume")))
{
int job, jflags, started_status;
jflags = JM_STOPPED|JM_FIRSTMATCH;
if (STREQ (temp, "exact"))
jflags |= JM_EXACT;
else if (STREQ (temp, "substring"))
jflags |= JM_SUBSTRING;
else
jflags |= JM_PREFIX;
job = get_job_by_name (words->word->word, jflags);
if (job != NO_JOB)
{
run_unwind_frame ("simple-command");
this_command_name = "fg";
last_shell_builtin = this_shell_builtin;
this_shell_builtin = builtin_address ("fg");
started_status = start_job (job, 1);
return ((started_status < 0) ? EXECUTION_FAILURE : started_status);
}
}
#endif /* JOB_CONTROL */
/* Remember the name of this command globally. */
this_command_name = words->word->word;
QUIT;
/* This command could be a shell builtin or a user-defined function.
We have already found special builtins by this time, so we do not
set builtin_is_special. If this is a function or builtin, and we
have pipes, then fork a subshell in here. Otherwise, just execute
the command directly. */
if (func == 0 && builtin == 0)
builtin = find_shell_builtin (this_command_name);
last_shell_builtin = this_shell_builtin;
this_shell_builtin = builtin;
if (builtin || func)
{
if (already_forked)
{
/* reset_terminating_signals (); */ /* XXX */
/* Cancel traps, in trap.c. */
restore_original_signals ();
if (async)
{
if ((simple_command->flags & CMD_STDIN_REDIR) &&
pipe_in == NO_PIPE &&
(stdin_redirects (simple_command->redirects) == 0))
async_redirect_stdin ();
setup_async_signals ();
}
subshell_level++;
execute_subshell_builtin_or_function
(words, simple_command->redirects, builtin, func,
pipe_in, pipe_out, async, fds_to_close,
simple_command->flags);
subshell_level--;
}
else
{
result = execute_builtin_or_function
(words, builtin, func, simple_command->redirects, fds_to_close,
simple_command->flags);
if (builtin)
{
if (result > EX_SHERRBASE)
{
result = builtin_status (result);
if (builtin_is_special)
special_builtin_failed = 1;
}
/* In POSIX mode, if there are assignment statements preceding
a special builtin, they persist after the builtin
completes. */
if (posixly_correct && builtin_is_special && temporary_env)
merge_temporary_env ();
}
else /* function */
{
if (result == EX_USAGE)
result = EX_BADUSAGE;
else if (result > EX_SHERRBASE)
result = EXECUTION_FAILURE;
}
set_pipestatus_from_exit (result);
goto return_result;
}
}
if (command_line == 0)
command_line = savestring (the_printed_command_except_trap);
#if defined (PROCESS_SUBSTITUTION)
if ((subshell_environment & SUBSHELL_COMSUB) && (simple_command->flags & CMD_NO_FORK) && fifos_pending() > 0)
simple_command->flags &= ~CMD_NO_FORK;
#endif
execute_disk_command (words, simple_command->redirects, command_line,
pipe_in, pipe_out, async, fds_to_close,
simple_command->flags);
return_result:
bind_lastarg (lastarg);
FREE (command_line);
dispose_words (words);
discard_unwind_frame ("simple-command");
this_command_name = (char *)NULL; /* points to freed memory now */
return (result);
}
/* Translate the special builtin exit statuses. We don't really need a
function for this; it's a placeholder for future work. */
static int
builtin_status (result)
int result;
{
int r;
switch (result)
{
case EX_USAGE:
r = EX_BADUSAGE;
break;
case EX_REDIRFAIL:
case EX_BADSYNTAX:
case EX_BADASSIGN:
case EX_EXPFAIL:
r = EXECUTION_FAILURE;
break;
default:
r = EXECUTION_SUCCESS;
break;
}
return (r);
}
static int
execute_builtin (builtin, words, flags, subshell)
sh_builtin_func_t *builtin;
WORD_LIST *words;
int flags, subshell;
{
int old_e_flag, result, eval_unwind;
int isbltinenv;
old_e_flag = exit_immediately_on_error;
/* The eval builtin calls parse_and_execute, which does not know about
the setting of flags, and always calls the execution functions with
flags that will exit the shell on an error if -e is set. If the
eval builtin is being called, and we're supposed to ignore the exit
value of the command, we turn the -e flag off ourselves, then
restore it when the command completes. */
if (subshell == 0 && builtin == eval_builtin && (flags & CMD_IGNORE_RETURN))
{
begin_unwind_frame ("eval_builtin");
unwind_protect_int (exit_immediately_on_error);
exit_immediately_on_error = 0;
eval_unwind = 1;
}
else
eval_unwind = 0;
/* The temporary environment for a builtin is supposed to apply to
all commands executed by that builtin. Currently, this is a
problem only with the `unset', `source' and `eval' builtins. */
isbltinenv = (builtin == source_builtin || builtin == eval_builtin || builtin == unset_builtin);
if (isbltinenv)
{
if (subshell == 0)
begin_unwind_frame ("builtin_env");
if (temporary_env)
{
push_scope (VC_BLTNENV, temporary_env);
if (subshell == 0)
add_unwind_protect (pop_scope, (flags & CMD_COMMAND_BUILTIN) ? 0 : "1");
temporary_env = (HASH_TABLE *)NULL;
}
}
/* `return' does a longjmp() back to a saved environment in execute_function.
If a variable assignment list preceded the command, and the shell is
running in POSIX mode, we need to merge that into the shell_variables
table, since `return' is a POSIX special builtin. */
if (posixly_correct && subshell == 0 && builtin == return_builtin && temporary_env)
{
begin_unwind_frame ("return_temp_env");
add_unwind_protect (merge_temporary_env, (char *)NULL);
}
result = ((*builtin) (words->next));
/* This shouldn't happen, but in case `return' comes back instead of
longjmp'ing, we need to unwind. */
if (posixly_correct && subshell == 0 && builtin == return_builtin && temporary_env)
discard_unwind_frame ("return_temp_env");
if (subshell == 0 && isbltinenv)
run_unwind_frame ("builtin_env");
if (eval_unwind)
{
exit_immediately_on_error += old_e_flag;
discard_unwind_frame ("eval_builtin");
}
return (result);
}
static int
execute_function (var, words, flags, fds_to_close, async, subshell)
SHELL_VAR *var;
WORD_LIST *words;
int flags;
struct fd_bitmap *fds_to_close;
int async, subshell;
{
int return_val, result;
COMMAND *tc, *fc, *save_current;
char *debug_trap, *error_trap, *return_trap;
#if defined (ARRAY_VARS)
SHELL_VAR *funcname_v, *nfv, *bash_source_v, *bash_lineno_v;
ARRAY *funcname_a, *bash_source_a, *bash_lineno_a;
#endif
FUNCTION_DEF *shell_fn;
char *sfile, *t;
static int funcnest = 0;
USE_VAR(fc);
#if defined (ARRAY_VARS)
GET_ARRAY_FROM_VAR ("FUNCNAME", funcname_v, funcname_a);
GET_ARRAY_FROM_VAR ("BASH_SOURCE", bash_source_v, bash_source_a);
GET_ARRAY_FROM_VAR ("BASH_LINENO", bash_lineno_v, bash_lineno_a);
#endif
tc = (COMMAND *)copy_command (function_cell (var));
if (tc && (flags & CMD_IGNORE_RETURN))
tc->flags |= CMD_IGNORE_RETURN;
if (subshell == 0)
{
begin_unwind_frame ("function_calling");
push_context (var->name, subshell, temporary_env);
add_unwind_protect (pop_context, (char *)NULL);
unwind_protect_int (line_number);
unwind_protect_int (return_catch_flag);
unwind_protect_jmp_buf (return_catch);
add_unwind_protect (dispose_command, (char *)tc);
unwind_protect_pointer (this_shell_function);
unwind_protect_int (loop_level);
}
else
push_context (var->name, subshell, temporary_env); /* don't unwind-protect for subshells */
temporary_env = (HASH_TABLE *)NULL;
this_shell_function = var;
make_funcname_visible (1);
debug_trap = TRAP_STRING(DEBUG_TRAP);
error_trap = TRAP_STRING(ERROR_TRAP);
return_trap = TRAP_STRING(RETURN_TRAP);
/* The order of the unwind protects for debug_trap, error_trap and
return_trap is important here! unwind-protect commands are run
in reverse order of registration. If this causes problems, take
out the xfree unwind-protect calls and live with the small memory leak. */
/* function_trace_mode != 0 means that all functions inherit the DEBUG trap.
if the function has the trace attribute set, it inherits the DEBUG trap */
if (debug_trap && ((trace_p (var) == 0) && function_trace_mode == 0))
{
if (subshell == 0)
{
debug_trap = savestring (debug_trap);
add_unwind_protect (xfree, debug_trap);
add_unwind_protect (set_debug_trap, debug_trap);
}
restore_default_signal (DEBUG_TRAP);
}
/* error_trace_mode != 0 means that functions inherit the ERR trap. */
if (error_trap && error_trace_mode == 0)
{
if (subshell == 0)
{
error_trap = savestring (error_trap);
add_unwind_protect (xfree, error_trap);
add_unwind_protect (set_error_trap, error_trap);
}
restore_default_signal (ERROR_TRAP);
}
/* Shell functions inherit the RETURN trap if function tracing is on
globally or on individually for this function. */
#if 0
if (return_trap && ((trace_p (var) == 0) && function_trace_mode == 0))
#else
if (return_trap && (signal_in_progress (DEBUG_TRAP) || ((trace_p (var) == 0) && function_trace_mode == 0)))
#endif
{
if (subshell == 0)
{
return_trap = savestring (return_trap);
add_unwind_protect (xfree, return_trap);
add_unwind_protect (set_return_trap, return_trap);
}
restore_default_signal (RETURN_TRAP);
}
funcnest++;
#if defined (ARRAY_VARS)
/* This is quite similar to the code in shell.c and elsewhere. */
shell_fn = find_function_def (this_shell_function->name);
sfile = shell_fn ? shell_fn->source_file : "";
array_push (funcname_a, this_shell_function->name);
array_push (bash_source_a, sfile);
t = itos (executing_line_number ());
array_push (bash_lineno_a, t);
free (t);
#endif
/* The temporary environment for a function is supposed to apply to
all commands executed within the function body. */
remember_args (words->next, 1);
/* Update BASH_ARGV and BASH_ARGC */
if (debugging_mode)
push_args (words->next);
/* Number of the line on which the function body starts. */
line_number = function_line_number = tc->line;
#if defined (JOB_CONTROL)
if (subshell)
stop_pipeline (async, (COMMAND *)NULL);
#endif
fc = tc;
return_catch_flag++;
return_val = setjmp (return_catch);
if (return_val)
{
result = return_catch_value;
/* Run the RETURN trap in the function's context. */
save_current = currently_executing_command;
run_return_trap ();
currently_executing_command = save_current;
}
else
{
/* Run the debug trap here so we can trap at the start of a function's
execution rather than the execution of the body's first command. */
showing_function_line = 1;
save_current = currently_executing_command;
result = run_debug_trap ();
#if defined (DEBUGGER)
/* In debugging mode, if the DEBUG trap returns a non-zero status, we
skip the command. */
if (debugging_mode == 0 || result == EXECUTION_SUCCESS)
{
showing_function_line = 0;
currently_executing_command = save_current;
result = execute_command_internal (fc, 0, NO_PIPE, NO_PIPE, fds_to_close);
/* Run the RETURN trap in the function's context */
save_current = currently_executing_command;
run_return_trap ();
currently_executing_command = save_current;
}
#else
result = execute_command_internal (fc, 0, NO_PIPE, NO_PIPE, fds_to_close);
save_current = currently_executing_command;
run_return_trap ();
currently_executing_command = save_current;
#endif
showing_function_line = 0;
}
/* Restore BASH_ARGC and BASH_ARGV */
if (debugging_mode)
pop_args ();
if (subshell == 0)
run_unwind_frame ("function_calling");
funcnest--;
#if defined (ARRAY_VARS)
/* These two variables cannot be unset, and cannot be affected by the
function. */
array_pop (bash_source_a);
array_pop (bash_lineno_a);
/* FUNCNAME can be unset, and so can potentially be changed by the
function. */
GET_ARRAY_FROM_VAR ("FUNCNAME", nfv, funcname_a);
if (nfv == funcname_v)
array_pop (funcname_a);
#endif
if (variable_context == 0 || this_shell_function == 0)
make_funcname_visible (0);
return (result);
}
/* A convenience routine for use by other parts of the shell to execute
a particular shell function. */
int
execute_shell_function (var, words)
SHELL_VAR *var;
WORD_LIST *words;
{
int ret;
struct fd_bitmap *bitmap;
bitmap = new_fd_bitmap (FD_BITMAP_DEFAULT_SIZE);
begin_unwind_frame ("execute-shell-function");
add_unwind_protect (dispose_fd_bitmap, (char *)bitmap);
ret = execute_function (var, words, 0, bitmap, 0, 0);
dispose_fd_bitmap (bitmap);
discard_unwind_frame ("execute-shell-function");
return ret;
}
/* Execute a shell builtin or function in a subshell environment. This
routine does not return; it only calls exit(). If BUILTIN is non-null,
it points to a function to call to execute a shell builtin; otherwise
VAR points at the body of a function to execute. WORDS is the arguments
to the command, REDIRECTS specifies redirections to perform before the
command is executed. */
static void
execute_subshell_builtin_or_function (words, redirects, builtin, var,
pipe_in, pipe_out, async, fds_to_close,
flags)
WORD_LIST *words;
REDIRECT *redirects;
sh_builtin_func_t *builtin;
SHELL_VAR *var;
int pipe_in, pipe_out, async;
struct fd_bitmap *fds_to_close;
int flags;
{
int result, r, funcvalue;
#if defined (JOB_CONTROL)
int jobs_hack;
jobs_hack = (builtin == jobs_builtin) &&
((subshell_environment & SUBSHELL_ASYNC) == 0 || pipe_out != NO_PIPE);
#endif
/* A subshell is neither a login shell nor interactive. */
login_shell = interactive = 0;
if (async)
subshell_environment |= SUBSHELL_ASYNC;
if (pipe_in != NO_PIPE || pipe_out != NO_PIPE)
subshell_environment |= SUBSHELL_PIPE;
maybe_make_export_env (); /* XXX - is this needed? */
#if defined (JOB_CONTROL)
/* Eradicate all traces of job control after we fork the subshell, so
all jobs begun by this subshell are in the same process group as
the shell itself. */
/* Allow the output of `jobs' to be piped. */
if (jobs_hack)
kill_current_pipeline ();
else
without_job_control ();
set_sigchld_handler ();
#endif /* JOB_CONTROL */
set_sigint_handler ();
if (fds_to_close)
close_fd_bitmap (fds_to_close);
do_piping (pipe_in, pipe_out);
if (do_redirections (redirects, RX_ACTIVE) != 0)
exit (EXECUTION_FAILURE);
if (builtin)
{
/* Give builtins a place to jump back to on failure,
so we don't go back up to main(). */
result = setjmp (top_level);
/* Give the return builtin a place to jump to when executed in a subshell
or pipeline */
funcvalue = 0;
if (return_catch_flag && builtin == return_builtin)
funcvalue = setjmp (return_catch);
if (result == EXITPROG)
exit (last_command_exit_value);
else if (result)
exit (EXECUTION_FAILURE);
else if (funcvalue)
exit (return_catch_value);
else
{
r = execute_builtin (builtin, words, flags, 1);
if (r == EX_USAGE)
r = EX_BADUSAGE;
exit (r);
}
}
else
exit (execute_function (var, words, flags, fds_to_close, async, 1));
}
/* Execute a builtin or function in the current shell context. If BUILTIN
is non-null, it is the builtin command to execute, otherwise VAR points
to the body of a function. WORDS are the command's arguments, REDIRECTS
are the redirections to perform. FDS_TO_CLOSE is the usual bitmap of
file descriptors to close.
If BUILTIN is exec_builtin, the redirections specified in REDIRECTS are
not undone before this function returns. */
static int
execute_builtin_or_function (words, builtin, var, redirects,
fds_to_close, flags)
WORD_LIST *words;
sh_builtin_func_t *builtin;
SHELL_VAR *var;
REDIRECT *redirects;
struct fd_bitmap *fds_to_close;
int flags;
{
int result;
REDIRECT *saved_undo_list;
sh_builtin_func_t *saved_this_shell_builtin;
if (do_redirections (redirects, RX_ACTIVE|RX_UNDOABLE) != 0)
{
cleanup_redirects (redirection_undo_list);
redirection_undo_list = (REDIRECT *)NULL;
dispose_exec_redirects ();
return (EX_REDIRFAIL); /* was EXECUTION_FAILURE */
}
saved_this_shell_builtin = this_shell_builtin;
saved_undo_list = redirection_undo_list;
/* Calling the "exec" builtin changes redirections forever. */
if (builtin == exec_builtin)
{
dispose_redirects (saved_undo_list);
saved_undo_list = exec_redirection_undo_list;
exec_redirection_undo_list = (REDIRECT *)NULL;
}
else
dispose_exec_redirects ();
if (saved_undo_list)
{
begin_unwind_frame ("saved redirects");
add_unwind_protect (cleanup_redirects, (char *)saved_undo_list);
}
redirection_undo_list = (REDIRECT *)NULL;
if (builtin)
result = execute_builtin (builtin, words, flags, 0);
else
result = execute_function (var, words, flags, fds_to_close, 0, 0);
/* We do this before undoing the effects of any redirections. */
if (ferror (stdout))
clearerr (stdout);
/* If we are executing the `command' builtin, but this_shell_builtin is
set to `exec_builtin', we know that we have something like
`command exec [redirection]', since otherwise `exec' would have
overwritten the shell and we wouldn't get here. In this case, we
want to behave as if the `command' builtin had not been specified
and preserve the redirections. */
if (builtin == command_builtin && this_shell_builtin == exec_builtin)
{
if (saved_undo_list)
dispose_redirects (saved_undo_list);
redirection_undo_list = exec_redirection_undo_list;
saved_undo_list = exec_redirection_undo_list = (REDIRECT *)NULL;
discard_unwind_frame ("saved_redirects");
}
if (saved_undo_list)
{
redirection_undo_list = saved_undo_list;
discard_unwind_frame ("saved redirects");
}
if (redirection_undo_list)
{
cleanup_redirects (redirection_undo_list);
redirection_undo_list = (REDIRECT *)NULL;
}
return (result);
}
void
setup_async_signals ()
{
#if defined (__BEOS__)
set_signal_handler (SIGHUP, SIG_IGN); /* they want csh-like behavior */
#endif
#if defined (JOB_CONTROL)
if (job_control == 0)
#endif
{
set_signal_handler (SIGINT, SIG_IGN);
set_signal_ignored (SIGINT);
set_signal_handler (SIGQUIT, SIG_IGN);
set_signal_ignored (SIGQUIT);
}
}
/* Execute a simple command that is hopefully defined in a disk file
somewhere.
1) fork ()
2) connect pipes
3) look up the command
4) do redirections
5) execve ()
6) If the execve failed, see if the file has executable mode set.
If so, and it isn't a directory, then execute its contents as
a shell script.
Note that the filename hashing stuff has to take place up here,
in the parent. This is probably why the Bourne style shells
don't handle it, since that would require them to go through
this gnarly hair, for no good reason.
NOTE: callers expect this to fork or exit(). */
static void
execute_disk_command (words, redirects, command_line, pipe_in, pipe_out,
async, fds_to_close, cmdflags)
WORD_LIST *words;
REDIRECT *redirects;
char *command_line;
int pipe_in, pipe_out, async;
struct fd_bitmap *fds_to_close;
int cmdflags;
{
char *pathname, *command, **args;
int nofork;
pid_t pid;
nofork = (cmdflags & CMD_NO_FORK); /* Don't fork, just exec, if no pipes */
pathname = words->word->word;
#if defined (RESTRICTED_SHELL)
command = (char *)NULL;
if (restricted && xstrchr (pathname, '/'))
{
internal_error (_("%s: restricted: cannot specify `/' in command names"),
pathname);
last_command_exit_value = EXECUTION_FAILURE;
/* If we're not going to fork below, we must already be in a child
process or a context in which it's safe to call exit(2). */
if (nofork && pipe_in == NO_PIPE && pipe_out == NO_PIPE)
exit (last_command_exit_value);
else
goto parent_return;
}
#endif /* RESTRICTED_SHELL */
command = search_for_command (pathname);
if (command)
{
maybe_make_export_env ();
put_command_name_into_env (command);
}
/* We have to make the child before we check for the non-existence
of COMMAND, since we want the error messages to be redirected. */
/* If we can get away without forking and there are no pipes to deal with,
don't bother to fork, just directly exec the command. */
if (nofork && pipe_in == NO_PIPE && pipe_out == NO_PIPE)
pid = 0;
else
pid = make_child (savestring (command_line), async);
if (pid == 0)
{
int old_interactive;
#if 0
/* This has been disabled for the time being. */
#if !defined (ARG_MAX) || ARG_MAX >= 10240
if (posixly_correct == 0)
put_gnu_argv_flags_into_env ((long)getpid (), glob_argv_flags);
#endif
#endif
/* Cancel traps, in trap.c. */
restore_original_signals ();
/* restore_original_signals may have undone the work done
by make_child to ensure that SIGINT and SIGQUIT are ignored
in asynchronous children. */
if (async)
{
if ((cmdflags & CMD_STDIN_REDIR) &&
pipe_in == NO_PIPE &&
(stdin_redirects (redirects) == 0))
async_redirect_stdin ();
setup_async_signals ();
}
/* This functionality is now provided by close-on-exec of the
file descriptors manipulated by redirection and piping.
Some file descriptors still need to be closed in all children
because of the way bash does pipes; fds_to_close is a
bitmap of all such file descriptors. */
if (fds_to_close)
close_fd_bitmap (fds_to_close);
do_piping (pipe_in, pipe_out);
old_interactive = interactive;
if (async)
interactive = 0;
subshell_environment = SUBSHELL_FORK;
if (redirects && (do_redirections (redirects, RX_ACTIVE) != 0))
{
#if defined (PROCESS_SUBSTITUTION)
/* Try to remove named pipes that may have been created as the
result of redirections. */
unlink_fifo_list ();
#endif /* PROCESS_SUBSTITUTION */
exit (EXECUTION_FAILURE);
}
if (async)
interactive = old_interactive;
if (command == 0)
{
internal_error (_("%s: command not found"), pathname);
exit (EX_NOTFOUND); /* Posix.2 says the exit status is 127 */
}
/* Execve expects the command name to be in args[0]. So we
leave it there, in the same format that the user used to
type it in. */
args = strvec_from_word_list (words, 0, 0, (int *)NULL);
exit (shell_execve (command, args, export_env));
}
else
{
parent_return:
/* Make sure that the pipes are closed in the parent. */
close_pipes (pipe_in, pipe_out);
#if defined (PROCESS_SUBSTITUTION) && defined (HAVE_DEV_FD)
unlink_fifo_list ();
#endif
FREE (command);
}
}
/* CPP defines to decide whether a particular index into the #! line
corresponds to a valid interpreter name or argument character, or
whitespace. The MSDOS define is to allow \r to be treated the same
as \n. */
#if !defined (MSDOS)
# define STRINGCHAR(ind) \
(ind < sample_len && !whitespace (sample[ind]) && sample[ind] != '\n')
# define WHITECHAR(ind) \
(ind < sample_len && whitespace (sample[ind]))
#else /* MSDOS */
# define STRINGCHAR(ind) \
(ind < sample_len && !whitespace (sample[ind]) && sample[ind] != '\n' && sample[ind] != '\r')
# define WHITECHAR(ind) \
(ind < sample_len && whitespace (sample[ind]))
#endif /* MSDOS */
static char *
getinterp (sample, sample_len, endp)
char *sample;
int sample_len, *endp;
{
register int i;
char *execname;
int start;
/* Find the name of the interpreter to exec. */
for (i = 2; i < sample_len && whitespace (sample[i]); i++)
;
for (start = i; STRINGCHAR(i); i++)
;
execname = substring (sample, start, i);
if (endp)
*endp = i;
return execname;
}
#if !defined (HAVE_HASH_BANG_EXEC)
/* If the operating system on which we're running does not handle
the #! executable format, then help out. SAMPLE is the text read
from the file, SAMPLE_LEN characters. COMMAND is the name of
the script; it and ARGS, the arguments given by the user, will
become arguments to the specified interpreter. ENV is the environment
to pass to the interpreter.
The word immediately following the #! is the interpreter to execute.
A single argument to the interpreter is allowed. */
static int
execute_shell_script (sample, sample_len, command, args, env)
char *sample;
int sample_len;
char *command;
char **args, **env;
{
char *execname, *firstarg;
int i, start, size_increment, larry;
/* Find the name of the interpreter to exec. */
execname = getinterp (sample, sample_len, &i);
size_increment = 1;
/* Now the argument, if any. */
for (firstarg = (char *)NULL, start = i; WHITECHAR(i); i++)
;
/* If there is more text on the line, then it is an argument for the
interpreter. */
if (STRINGCHAR(i))
{
for (start = i; STRINGCHAR(i); i++)
;
firstarg = substring ((char *)sample, start, i);
size_increment = 2;
}
larry = strvec_len (args) + size_increment;
args = strvec_resize (args, larry + 1);
for (i = larry - 1; i; i--)
args[i] = args[i - size_increment];
args[0] = execname;
if (firstarg)
{
args[1] = firstarg;
args[2] = command;
}
else
args[1] = command;
args[larry] = (char *)NULL;
return (shell_execve (execname, args, env));
}
#undef STRINGCHAR
#undef WHITECHAR
#endif /* !HAVE_HASH_BANG_EXEC */
static void
initialize_subshell ()
{
#if defined (ALIAS)
/* Forget about any aliases that we knew of. We are in a subshell. */
delete_all_aliases ();
#endif /* ALIAS */
#if defined (HISTORY)
/* Forget about the history lines we have read. This is a non-interactive
subshell. */
history_lines_this_session = 0;
#endif
#if defined (JOB_CONTROL)
/* Forget about the way job control was working. We are in a subshell. */
without_job_control ();
set_sigchld_handler ();
init_job_stats ();
#endif /* JOB_CONTROL */
/* Reset the values of the shell flags and options. */
reset_shell_flags ();
reset_shell_options ();
reset_shopt_options ();
/* Zero out builtin_env, since this could be a shell script run from a
sourced file with a temporary environment supplied to the `source/.'
builtin. Such variables are not supposed to be exported (empirical
testing with sh and ksh). Just throw it away; don't worry about a
memory leak. */
if (vc_isbltnenv (shell_variables))
shell_variables = shell_variables->down;
clear_unwind_protect_list (0);
/* XXX -- are there other things we should be resetting here? */
parse_and_execute_level = 0; /* nothing left to restore it */
/* We're no longer inside a shell function. */
variable_context = return_catch_flag = 0;
/* If we're not interactive, close the file descriptor from which we're
reading the current shell script. */
if (interactive_shell == 0)
unset_bash_input (0);
}
#if defined (HAVE_SETOSTYPE) && defined (_POSIX_SOURCE)
# define SETOSTYPE(x) __setostype(x)
#else
# define SETOSTYPE(x)
#endif
#define READ_SAMPLE_BUF(file, buf, len) \
do \
{ \
fd = open(file, O_RDONLY); \
if (fd >= 0) \
{ \
len = read (fd, buf, 80); \
close (fd); \
} \
else \
len = -1; \
} \
while (0)
/* Call execve (), handling interpreting shell scripts, and handling
exec failures. */
int
shell_execve (command, args, env)
char *command;
char **args, **env;
{
struct stat finfo;
int larray, i, fd;
char sample[80];
int sample_len;
SETOSTYPE (0); /* Some systems use for USG/POSIX semantics */
execve (command, args, env);
i = errno; /* error from execve() */
SETOSTYPE (1);
/* If we get to this point, then start checking out the file.
Maybe it is something we can hack ourselves. */
if (i != ENOEXEC)
{
if ((stat (command, &finfo) == 0) && (S_ISDIR (finfo.st_mode)))
internal_error (_("%s: is a directory"), command);
else if (executable_file (command) == 0)
{
errno = i;
file_error (command);
}
/* errors not involving the path argument to execve. */
else if (i == E2BIG || i == ENOMEM)
{
errno = i;
file_error (command);
}
else
{
/* The file has the execute bits set, but the kernel refuses to
run it for some reason. See why. */
#if defined (HAVE_HASH_BANG_EXEC)
READ_SAMPLE_BUF (command, sample, sample_len);
if (sample_len > 2 && sample[0] == '#' && sample[1] == '!')
{
char *interp;
int ilen;
interp = getinterp (sample, sample_len, (int *)NULL);
ilen = strlen (interp);
errno = i;
if (interp[ilen - 1] == '\r')
{
interp = xrealloc (interp, ilen + 2);
interp[ilen - 1] = '^';
interp[ilen] = 'M';
interp[ilen + 1] = '\0';
}
sys_error (_("%s: %s: bad interpreter"), command, interp ? interp : "");
FREE (interp);
return (EX_NOEXEC);
}
#endif
errno = i;
file_error (command);
}
return ((i == ENOENT) ? EX_NOTFOUND : EX_NOEXEC); /* XXX Posix.2 says that exit status is 126 */
}
/* This file is executable.
If it begins with #!, then help out people with losing operating
systems. Otherwise, check to see if it is a binary file by seeing
if the contents of the first line (or up to 80 characters) are in the
ASCII set. If it's a text file, execute the contents as shell commands,
otherwise return 126 (EX_BINARY_FILE). */
READ_SAMPLE_BUF (command, sample, sample_len);
if (sample_len == 0)
return (EXECUTION_SUCCESS);
/* Is this supposed to be an executable script?
If so, the format of the line is "#! interpreter [argument]".
A single argument is allowed. The BSD kernel restricts
the length of the entire line to 32 characters (32 bytes
being the size of the BSD exec header), but we allow 80
characters. */
if (sample_len > 0)
{
#if !defined (HAVE_HASH_BANG_EXEC)
if (sample_len > 2 && sample[0] == '#' && sample[1] == '!')
return (execute_shell_script (sample, sample_len, command, args, env));
else
#endif
if (check_binary_file (sample, sample_len))
{
internal_error (_("%s: cannot execute binary file"), command);
return (EX_BINARY_FILE);
}
}
/* We have committed to attempting to execute the contents of this file
as shell commands. */
initialize_subshell ();
set_sigint_handler ();
/* Insert the name of this shell into the argument list. */
larray = strvec_len (args) + 1;
args = strvec_resize (args, larray + 1);
for (i = larray - 1; i; i--)
args[i] = args[i - 1];
args[0] = shell_name;
args[1] = command;
args[larray] = (char *)NULL;
if (args[0][0] == '-')
args[0]++;
#if defined (RESTRICTED_SHELL)
if (restricted)
change_flag ('r', FLAG_OFF);
#endif
if (subshell_argv)
{
/* Can't free subshell_argv[0]; that is shell_name. */
for (i = 1; i < subshell_argc; i++)
free (subshell_argv[i]);
free (subshell_argv);
}
dispose_command (currently_executing_command); /* XXX */
currently_executing_command = (COMMAND *)NULL;
subshell_argc = larray;
subshell_argv = args;
subshell_envp = env;
unbind_args (); /* remove the positional parameters */
longjmp (subshell_top_level, 1);
/*NOTREACHED*/
}
static int
execute_intern_function (name, function)
WORD_DESC *name;
COMMAND *function;
{
SHELL_VAR *var;
if (check_identifier (name, posixly_correct) == 0)
{
if (posixly_correct && interactive_shell == 0)
{
last_command_exit_value = EX_USAGE;
jump_to_top_level (ERREXIT);
}
return (EXECUTION_FAILURE);
}
var = find_function (name->word);
if (var && (readonly_p (var) || noassign_p (var)))
{
if (readonly_p (var))
internal_error (_("%s: readonly function"), var->name);
return (EXECUTION_FAILURE);
}
bind_function (name->word, function);
return (EXECUTION_SUCCESS);
}
#if defined (INCLUDE_UNUSED)
#if defined (PROCESS_SUBSTITUTION)
void
close_all_files ()
{
register int i, fd_table_size;
fd_table_size = getdtablesize ();
if (fd_table_size > 256) /* clamp to a reasonable value */
fd_table_size = 256;
for (i = 3; i < fd_table_size; i++)
close (i);
}
#endif /* PROCESS_SUBSTITUTION */
#endif
static void
close_pipes (in, out)
int in, out;
{
if (in >= 0)
close (in);
if (out >= 0)
close (out);
}
static void
dup_error (oldd, newd)
int oldd, newd;
{
sys_error (_("cannot duplicate fd %d to fd %d"), oldd, newd);
}
/* Redirect input and output to be from and to the specified pipes.
NO_PIPE and REDIRECT_BOTH are handled correctly. */
static void
do_piping (pipe_in, pipe_out)
int pipe_in, pipe_out;
{
if (pipe_in != NO_PIPE)
{
if (dup2 (pipe_in, 0) < 0)
dup_error (pipe_in, 0);
if (pipe_in > 0)
close (pipe_in);
}
if (pipe_out != NO_PIPE)
{
if (pipe_out != REDIRECT_BOTH)
{
if (dup2 (pipe_out, 1) < 0)
dup_error (pipe_out, 1);
if (pipe_out == 0 || pipe_out > 1)
close (pipe_out);
}
else
{
if (dup2 (1, 2) < 0)
dup_error (1, 2);
}
}
}