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execute_cmd.c
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/* execute_cmd.c -- Execute a COMMAND structure. */
/* Copyright (C) 1987-2022 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 <time.h>
#include <stdlib.h>
#include <string.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>
#if defined (HAVE_SYS_PARAM_H)
# 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
#define NEED_SH_SETLINEBUF_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 "parser.h"
#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 "builtins/getopt.h"
#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
#if defined (HAVE_MBSTR_H) && defined (HAVE_MBSCHR)
# include <mbstr.h> /* mbschr */
#endif
extern int command_string_index;
extern char *the_printed_command;
extern time_t shell_start_time;
#if defined (HAVE_GETTIMEOFDAY)
extern struct timeval shellstart;
#endif
#if 0
extern char *glob_argv_flags;
#endif
extern int close PARAMS((int));
/* Static functions defined and used in this file. */
static void close_pipes PARAMS((int, int));
static void do_piping PARAMS((int, int));
static void bind_lastarg PARAMS((char *));
static int shell_control_structure PARAMS((enum command_type));
static void cleanup_redirects PARAMS((REDIRECT *));
#if defined (JOB_CONTROL)
static int restore_signal_mask PARAMS((sigset_t *));
#endif
static int builtin_status PARAMS((int));
static int execute_for_command PARAMS((FOR_COM *));
#if defined (SELECT_COMMAND)
static int displen PARAMS((const char *));
static int print_index_and_element PARAMS((int, int, WORD_LIST *));
static void indent PARAMS((int, int));
static void print_select_list PARAMS((WORD_LIST *, int, int, int));
static char *select_query PARAMS((WORD_LIST *, int, char *, int));
static int execute_select_command PARAMS((SELECT_COM *));
#endif
#if defined (DPAREN_ARITHMETIC)
static int execute_arith_command PARAMS((ARITH_COM *));
#endif
#if defined (COND_COMMAND)
static int execute_cond_node PARAMS((COND_COM *));
static int execute_cond_command PARAMS((COND_COM *));
#endif
#if defined (COMMAND_TIMING)
static int mkfmt PARAMS((char *, int, int, time_t, int));
static void print_formatted_time PARAMS((FILE *, char *,
time_t, int, time_t, int,
time_t, int, int));
static int time_command PARAMS((COMMAND *, int, int, int, struct fd_bitmap *));
#endif
#if defined (ARITH_FOR_COMMAND)
static intmax_t eval_arith_for_expr PARAMS((WORD_LIST *, int *));
static int execute_arith_for_command PARAMS((ARITH_FOR_COM *));
#endif
static int execute_case_command PARAMS((CASE_COM *));
static int execute_while_command PARAMS((WHILE_COM *));
static int execute_until_command PARAMS((WHILE_COM *));
static int execute_while_or_until PARAMS((WHILE_COM *, int));
static int execute_if_command PARAMS((IF_COM *));
static int execute_null_command PARAMS((REDIRECT *, int, int, int));
static void fix_assignment_words PARAMS((WORD_LIST *));
static void fix_arrayref_words PARAMS((WORD_LIST *));
static int execute_simple_command PARAMS((SIMPLE_COM *, int, int, int, struct fd_bitmap *));
static int execute_builtin PARAMS((sh_builtin_func_t *, WORD_LIST *, int, int));
static int execute_function PARAMS((SHELL_VAR *, WORD_LIST *, int, struct fd_bitmap *, int, int));
static int execute_builtin_or_function PARAMS((WORD_LIST *, sh_builtin_func_t *,
SHELL_VAR *,
REDIRECT *, struct fd_bitmap *, int));
static void execute_subshell_builtin_or_function PARAMS((WORD_LIST *, REDIRECT *,
sh_builtin_func_t *,
SHELL_VAR *,
int, int, int,
struct fd_bitmap *,
int));
static int execute_disk_command PARAMS((WORD_LIST *, REDIRECT *, char *,
int, int, int, struct fd_bitmap *, int));
static char *getinterp PARAMS((char *, int, int *));
static void initialize_subshell PARAMS((void));
static int execute_in_subshell PARAMS((COMMAND *, int, int, int, struct fd_bitmap *));
#if defined (COPROCESS_SUPPORT)
static void coproc_setstatus PARAMS((struct coproc *, int));
static int execute_coproc PARAMS((COMMAND *, int, int, struct fd_bitmap *));
#endif
static int execute_pipeline PARAMS((COMMAND *, int, int, int, struct fd_bitmap *));
static int execute_connection PARAMS((COMMAND *, int, int, int, struct fd_bitmap *));
static int execute_intern_function PARAMS((WORD_DESC *, FUNCTION_DEF *));
/* 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. */
volatile 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;
/* Are we currently ignoring the -e option for the duration of a builtin's
execution? */
int builtin_ignoring_errexit = 0;
/* 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;
int executing_command_builtin = 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 connection_count;
/* $LINENO ($BASH_LINENO) for use by an ERR trap. Global so parse_and_execute
can save and restore it. */
int line_number_for_err_trap;
/* A convenience macro to avoid resetting line_number_for_err_trap while
running the ERR trap. */
#define SET_LINE_NUMBER(v) \
do { \
line_number = v; \
if (signal_in_progress (ERROR_TRAP) == 0 && running_trap != (ERROR_TRAP + 1)) \
line_number_for_err_trap = line_number; \
} while (0)
/* This can't be in executing_line_number() because that's used for LINENO
and we want LINENO to reflect the line number of commands run during
the ERR trap. Right now this is only used to push to BASH_LINENO. */
#define GET_LINE_NUMBER() \
(signal_in_progress (ERROR_TRAP) && running_trap == ERROR_TRAP+1) \
? line_number_for_err_trap \
: executing_line_number ()
/* A sort of function nesting level counter */
int funcnest = 0;
int funcnest_max = 0;
int evalnest = 0;
int evalnest_max = EVALNEST_MAX;
int sourcenest = 0;
int sourcenest_max = SOURCENEST_MAX;
volatile int from_return_trap = 0;
int lastpipe_opt = 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)
if (currently_executing_command->type == cm_arith)
return currently_executing_command->value.Arith->line;
#endif
#if defined (ARITH_FOR_COMMAND)
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 && executing_list == 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);
}
void
undo_partial_redirects ()
{
if (redirection_undo_list)
{
cleanup_redirects (redirection_undo_list);
redirection_undo_list = (REDIRECT *)NULL;
}
}
#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;
}
}
void
dispose_partial_redirects ()
{
if (redirection_undo_list)
{
dispose_redirects (redirection_undo_list);
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 (void)
{
register int i;
int f, fd_table_size;
fd_table_size = custom_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
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 asynchronously.
COMMAND is exactly what read_command () places into GLOBAL_COMMAND.
ASYNCHRONOUS, 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, fork_flags;
REDIRECT *my_undo_list, *exec_undo_list;
char *tcmd;
volatile int save_line_number;
#if defined (PROCESS_SUBSTITUTION)
volatile int ofifo, nfifo, osize, saved_fifo;
volatile void *ofifo_list;
#endif
if (breaking || continuing)
return (last_command_exit_value);
if (read_but_dont_execute)
return (last_command_exit_value);
if (command == 0)
return (EXECUTION_SUCCESS);
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 (last_command_exit_value = execute_coproc (command, pipe_in, pipe_out, fds_to_close));
#endif
user_subshell = command->type == cm_subshell || ((command->flags & CMD_WANT_SUBSHELL) != 0);
#if defined (TIME_BEFORE_SUBSHELL)
if ((command->flags & CMD_TIME_PIPELINE) && user_subshell && asynchronous == 0)
{
command->flags |= CMD_FORCE_SUBSHELL;
exec_result = time_command (command, asynchronous, pipe_in, pipe_out, fds_to_close);
currently_executing_command = (COMMAND *)NULL;
return (exec_result);
}
#endif
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;
int s;
char *p;
/* Fork a subshell, turn off the subshell bit, turn off job
control and call execute_command () on the command again. */
save_line_number = line_number;
if (command->type == cm_subshell)
SET_LINE_NUMBER (command->value.Subshell->line); /* XXX - save value? */
/* Otherwise we defer setting line_number */
tcmd = make_command_string (command);
fork_flags = asynchronous ? FORK_ASYNC : 0;
paren_pid = make_child (p = savestring (tcmd), fork_flags);
if (user_subshell && signal_is_trapped (ERROR_TRAP) &&
signal_in_progress (DEBUG_TRAP) == 0 && running_trap == 0)
{
FREE (the_printed_command_except_trap);
the_printed_command_except_trap = savestring (the_printed_command);
}
if (paren_pid == 0)
{
#if defined (JOB_CONTROL)
FREE (p); /* child doesn't use pointer */
#endif
/* We want to run the exit trap for forced {} subshells, and we
want to note this before execute_in_subshell modifies the
COMMAND struct. Need to keep in mind that execute_in_subshell
runs the exit trap for () subshells itself. */
/* This handles { command; } & */
s = user_subshell == 0 && command->type == cm_group && pipe_in == NO_PIPE && pipe_out == NO_PIPE && asynchronous;
/* run exit trap for : | { ...; } and { ...; } | : */
/* run exit trap for : | ( ...; ) and ( ...; ) | : */
s += user_subshell == 0 && command->type == cm_group && (pipe_in != NO_PIPE || pipe_out != NO_PIPE) && asynchronous == 0;
last_command_exit_value = execute_in_subshell (command, asynchronous, pipe_in, pipe_out, fds_to_close);
if (s)
subshell_exit (last_command_exit_value);
else
sh_exit (last_command_exit_value);
/* NOTREACHED */
}
else
{
close_pipes (pipe_in, pipe_out);
#if defined (PROCESS_SUBSTITUTION) && defined (HAVE_DEV_FD)
if (variable_context == 0) /* wait until shell function completes */
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);
line_number = save_line_number;
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;
exec_result = wait_for (paren_pid, 0);
/* If we have to, invert the return value. */
if (invert)
exec_result = ((exec_result == EXECUTION_SUCCESS)
? EXECUTION_FAILURE
: EXECUTION_SUCCESS);
last_command_exit_value = exec_result;
if (user_subshell && was_error_trap && ignore_return == 0 && invert == 0 && exec_result != EXECUTION_SUCCESS)
{
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)
{
run_pending_traps ();
jump_to_top_level (ERREXIT);
}
return (last_command_exit_value);
}
else
{
DESCRIBE_PID (paren_pid);
run_pending_traps ();
/* Posix 2013 2.9.3.1: "the exit status of an asynchronous list
shall be zero." */
last_command_exit_value = 0;
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);
#if defined (PROCESS_SUBSTITUTION)
# if !defined (HAVE_DEV_FD)
reap_procsubs ();
# endif
/* XXX - also if sourcelevel != 0? */
if (variable_context != 0 || executing_list)
{
ofifo = num_fifos ();
ofifo_list = copy_fifo_list ((int *)&osize);
begin_unwind_frame ("internal_fifos");
if (ofifo_list)
add_unwind_protect (xfree, ofifo_list);
saved_fifo = 1;
}
else
saved_fifo = 0;
#endif
/* Handle WHILE FOR CASE etc. with redirections. (Also '&' input
redirection.) */
was_error_trap = signal_is_trapped (ERROR_TRAP) && signal_is_ignored (ERROR_TRAP) == 0;
ignore_return = (command->flags & CMD_IGNORE_RETURN) != 0;
if (do_redirections (command->redirects, RX_ACTIVE|RX_UNDOABLE) != 0)
{
undo_partial_redirects ();
dispose_exec_redirects ();
#if defined (PROCESS_SUBSTITUTION)
if (saved_fifo)
{
free ((void *)ofifo_list);
discard_unwind_frame ("internal_fifos");
}
#endif
/* Handle redirection error as command failure if errexit set. */
last_command_exit_value = EXECUTION_FAILURE;
if (ignore_return == 0 && invert == 0 && pipe_in == NO_PIPE && pipe_out == NO_PIPE)
{
if (was_error_trap)
{
save_line_number = line_number;
line_number = line_number_for_err_trap;
run_error_trap ();
line_number = save_line_number;
}
if (exit_immediately_on_error)
{
run_pending_traps ();
jump_to_top_level (ERREXIT);
}
}
return (last_command_exit_value);
}
my_undo_list = redirection_undo_list;
redirection_undo_list = (REDIRECT *)NULL;
exec_undo_list = exec_redirection_undo_list;
exec_redirection_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);
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
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;
SET_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. Don't worry about
whether or not last_made_pid == last_pid; already_making_children
tells us whether or not there are unwaited-for children to wait
for and reap. */
if (already_making_children && pipe_out == NO_PIPE)
{
stop_pipeline (asynchronous, (COMMAND *)NULL);
if (asynchronous)
{
DESCRIBE_PID (last_made_pid);
exec_result = EXECUTION_SUCCESS;
invert = 0; /* async commands always succeed */
}
else
#if !defined (JOB_CONTROL)
/* Do not wait for asynchronous processes started from
startup files. */
if (last_made_pid != NO_PID && last_made_pid != last_asynchronous_pid)
#else
if (last_made_pid != NO_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, 0);
}
}
/* 2009/02/13 -- pipeline failure is processed elsewhere. This handles
only the failure of a simple command. We don't want to run the error
trap if the command run by the `command' builtin fails; we want to
defer that until the command builtin itself returns failure. */
/* 2020/07/14 -- this changes with how the command builtin is handled */
if (was_error_trap && ignore_return == 0 && invert == 0 &&
pipe_in == NO_PIPE && pipe_out == NO_PIPE &&
(command->value.Simple->flags & CMD_COMMAND_BUILTIN) == 0 &&
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 ();
/* Undo redirections before running exit trap on the way out of
set -e. Report by Mark Farrell 5/19/2014 */
if (exit_immediately_on_error && signal_is_trapped (0) &&
unwind_protect_tag_on_stack ("saved-redirects"))
run_unwind_frame ("saved-redirects");
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