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execute_cmd.c
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execute_cmd.c
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/* execute_cmd.c -- Execute a COMMAND structure. */
/* Copyright (C) 1987-2009 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 3 of the License, 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. If not, see <http://www.gnu.org/licenses/>.
*/
#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
#define NEED_FPURGE_DECL
#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 expand_aliases;
extern int autocd;
extern int breaking, continuing, loop_level;
extern int parse_and_execute_level, running_trap, sourcelevel;
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 *));
#if defined (COPROCESS_SUPPORT)
static int execute_coproc __P((COMMAND *, int, int, struct fd_bitmap *));
#endif
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 *));
/* 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;
/* 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;
/* When greater than zero, value is the `level' of builtins we are
currently executing (e.g. `eval echo a' would have it set to 2). */
int executing_builtin = 0;
/* Non-zero if we are executing a command list (a;b;c, etc.) */
int executing_list = 0;
/* Non-zero if failing commands in a command substitution should not exit the
shell even if -e is set. Used to pass the CMD_IGNORE_RETURN flag down to
commands run in command substitutions by parse_and_execute. */
int comsub_ignore_return = 0;
/* 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 stat SB; /* used for debugging */
static int special_builtin_failed;
static COMMAND *currently_executing_command;
/* The line number that the currently executing function starts on. */
static int function_line_number;
/* 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;
/* A sort of function nesting level counter */
static int funcnest = 0;
int funcnest_max = 0; /* XXX - for bash-4.2 */
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, user_subshell, 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 defined (COPROCESS_SUPPORT)
if (command->type == cm_coproc)
return (execute_coproc (command, pipe_in, pipe_out, fds_to_close));
#endif
user_subshell = command->type == cm_subshell || ((command->flags & CMD_WANT_SUBSHELL) != 0);
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. */
line_number_for_err_trap = line_number;
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)
{
was_error_trap = signal_is_trapped (ERROR_TRAP) && signal_is_ignored (ERROR_TRAP) == 0;
invert = (command->flags & CMD_INVERT_RETURN) != 0;
ignore_return = (command->flags & CMD_IGNORE_RETURN) != 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;
if (user_subshell && was_error_trap && ignore_return == 0 && invert == 0 && exec_result != EXECUTION_SUCCESS)
{
last_command_exit_value = exec_result;
save_line_number = line_number;
line_number = line_number_for_err_trap;
run_error_trap ();
line_number = save_line_number;
}
if (user_subshell && ignore_return == 0 && invert == 0 && exit_immediately_on_error && exec_result != EXECUTION_SUCCESS)
{
last_command_exit_value = exec_result;
run_pending_traps ();
jump_to_top_level (ERREXIT);
}
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);
}
}
/* 2009/02/13 -- pipeline failure is processed elsewhere. This handles
only the failure of a simple command. */
if (was_error_trap && ignore_return == 0 && invert == 0 && pipe_in == NO_PIPE && pipe_out == NO_PIPE && exec_result != EXECUTION_SUCCESS)
{
last_command_exit_value = exec_result;
line_number = line_number_for_err_trap;
run_error_trap ();
line_number = save_line_number;
}
if (ignore_return == 0 && invert == 0 &&
((posixly_correct && interactive == 0 && special_builtin_failed) ||
(exit_immediately_on_error && pipe_in == NO_PIPE && pipe_out == NO_PIPE && 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:
was_error_trap = signal_is_trapped (ERROR_TRAP) && signal_is_ignored (ERROR_TRAP) == 0;
if (ignore_return)
command->value.Arith->flags |= CMD_IGNORE_RETURN;
line_number_for_err_trap = save_line_number = line_number;
exec_result = execute_arith_command (command->value.Arith);
line_number = save_line_number;
if (was_error_trap && ignore_return == 0 && invert == 0 && exec_result != EXECUTION_SUCCESS)
{
last_command_exit_value = exec_result;
save_line_number = line_number;
line_number = line_number_for_err_trap;
run_error_trap ();
line_number = save_line_number;
}
if (ignore_return == 0 && invert == 0 && exit_immediately_on_error && exec_result != EXECUTION_SUCCESS)
{
last_command_exit_value = exec_result;
run_pending_traps ();
jump_to_top_level (ERREXIT);
}
break;
#endif
#if defined (COND_COMMAND)
case cm_cond:
was_error_trap = signal_is_trapped (ERROR_TRAP) && signal_is_ignored (ERROR_TRAP) == 0;
if (ignore_return)
command->value.Cond->flags |= CMD_IGNORE_RETURN;
line_number_for_err_trap = save_line_number = line_number;
exec_result = execute_cond_command (command->value.Cond);
line_number = save_line_number;
if (was_error_trap && ignore_return == 0 && invert == 0 && exec_result != EXECUTION_SUCCESS)
{
last_command_exit_value = exec_result;
save_line_number = line_number;
line_number = line_number_for_err_trap;
run_error_trap ();
line_number = save_line_number;
}
if (ignore_return == 0 && invert == 0 && exit_immediately_on_error && exec_result != EXECUTION_SUCCESS)
{
last_command_exit_value = exec_result;
run_pending_traps ();
jump_to_top_level (ERREXIT);
}
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)