busybox/findutils/xargs.c
Ron Yorston 1c462d47a0 xargs: restore correct behaviour of -n option
Since commit 1ff7002b1 (xargs: fix handling of quoted arguments, closes
11441) the -n option hasn't worked properly:

   $ echo 1 2 3 | xargs -n 1 echo
   1
   2

   3

   $

Because state is now remembered between calls to process_stdin() it's
necessary to update the state before any premature return.

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2020-04-29 15:53:51 +02:00

783 lines
21 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Mini xargs implementation for busybox
*
* (C) 2002,2003 by Vladimir Oleynik <dzo@simtreas.ru>
*
* Special thanks
* - Mark Whitley and Glenn McGrath for stimulus to rewrite :)
* - Mike Rendell <michael@cs.mun.ca>
* and David MacKenzie <djm@gnu.ai.mit.edu>.
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*
* xargs is described in the Single Unix Specification v3 at
* http://www.opengroup.org/onlinepubs/007904975/utilities/xargs.html
*/
//config:config XARGS
//config: bool "xargs (7.2 kb)"
//config: default y
//config: help
//config: xargs is used to execute a specified command for
//config: every item from standard input.
//config:
//config:config FEATURE_XARGS_SUPPORT_CONFIRMATION
//config: bool "Enable -p: prompt and confirmation"
//config: default y
//config: depends on XARGS
//config: help
//config: Support -p: prompt the user whether to run each command
//config: line and read a line from the terminal.
//config:
//config:config FEATURE_XARGS_SUPPORT_QUOTES
//config: bool "Enable single and double quotes and backslash"
//config: default y
//config: depends on XARGS
//config: help
//config: Support quoting in the input.
//config:
//config:config FEATURE_XARGS_SUPPORT_TERMOPT
//config: bool "Enable -x: exit if -s or -n is exceeded"
//config: default y
//config: depends on XARGS
//config: help
//config: Support -x: exit if the command size (see the -s or -n option)
//config: is exceeded.
//config:
//config:config FEATURE_XARGS_SUPPORT_ZERO_TERM
//config: bool "Enable -0: NUL-terminated input"
//config: default y
//config: depends on XARGS
//config: help
//config: Support -0: input items are terminated by a NUL character
//config: instead of whitespace, and the quotes and backslash
//config: are not special.
//config:
//config:config FEATURE_XARGS_SUPPORT_REPL_STR
//config: bool "Enable -I STR: string to replace"
//config: default y
//config: depends on XARGS
//config: help
//config: Support -I STR and -i[STR] options.
//config:
//config:config FEATURE_XARGS_SUPPORT_PARALLEL
//config: bool "Enable -P N: processes to run in parallel"
//config: default y
//config: depends on XARGS
//config:
//config:config FEATURE_XARGS_SUPPORT_ARGS_FILE
//config: bool "Enable -a FILE: use FILE instead of stdin"
//config: default y
//config: depends on XARGS
//applet:IF_XARGS(APPLET_NOEXEC(xargs, xargs, BB_DIR_USR_BIN, BB_SUID_DROP, xargs))
//kbuild:lib-$(CONFIG_XARGS) += xargs.o
#include "libbb.h"
#include "common_bufsiz.h"
/* This is a NOEXEC applet. Be very careful! */
//#define dbg_msg(...) bb_error_msg(__VA_ARGS__)
#define dbg_msg(...) ((void)0)
#ifdef TEST
# ifndef ENABLE_FEATURE_XARGS_SUPPORT_CONFIRMATION
# define ENABLE_FEATURE_XARGS_SUPPORT_CONFIRMATION 1
# endif
# ifndef ENABLE_FEATURE_XARGS_SUPPORT_QUOTES
# define ENABLE_FEATURE_XARGS_SUPPORT_QUOTES 1
# endif
# ifndef ENABLE_FEATURE_XARGS_SUPPORT_TERMOPT
# define ENABLE_FEATURE_XARGS_SUPPORT_TERMOPT 1
# endif
# ifndef ENABLE_FEATURE_XARGS_SUPPORT_ZERO_TERM
# define ENABLE_FEATURE_XARGS_SUPPORT_ZERO_TERM 1
# endif
#endif
struct globals {
char **args;
#if ENABLE_FEATURE_XARGS_SUPPORT_REPL_STR
char **argv;
const char *repl_str;
char eol_ch;
#endif
const char *eof_str;
int idx;
#if ENABLE_FEATURE_XARGS_SUPPORT_PARALLEL
int running_procs;
int max_procs;
#endif
smalluint xargs_exitcode;
#if ENABLE_FEATURE_XARGS_SUPPORT_QUOTES
#define NORM 0
#define QUOTE 1
#define BACKSLASH 2
#define SPACE 4
smalluint process_stdin__state;
char process_stdin__q;
#endif
} FIX_ALIASING;
#define G (*(struct globals*)bb_common_bufsiz1)
#define INIT_G() do { \
setup_common_bufsiz(); \
IF_FEATURE_XARGS_SUPPORT_REPL_STR(G.repl_str = "{}";) \
IF_FEATURE_XARGS_SUPPORT_REPL_STR(G.eol_ch = '\n';) \
/* Even zero values are set because we are NOEXEC applet */ \
G.eof_str = NULL; \
G.idx = 0; \
IF_FEATURE_XARGS_SUPPORT_PARALLEL(G.running_procs = 0;) \
IF_FEATURE_XARGS_SUPPORT_PARALLEL(G.max_procs = 1;) \
G.xargs_exitcode = 0; \
IF_FEATURE_XARGS_SUPPORT_QUOTES(G.process_stdin__state = NORM;) \
IF_FEATURE_XARGS_SUPPORT_QUOTES(G.process_stdin__q = '\0';) \
} while (0)
/*
* Returns 0 if xargs should continue (but may set G.xargs_exitcode to 123).
* Else sets G.xargs_exitcode to error code and returns nonzero.
*
* If G.max_procs == 0, performs final waitpid() loop for all children.
*/
static int xargs_exec(void)
{
int status;
#if !ENABLE_FEATURE_XARGS_SUPPORT_PARALLEL
status = spawn_and_wait(G.args);
#else
if (G.max_procs == 1) {
status = spawn_and_wait(G.args);
} else {
pid_t pid;
int wstat;
again:
if (G.running_procs >= G.max_procs)
pid = safe_waitpid(-1, &wstat, 0);
else
pid = wait_any_nohang(&wstat);
if (pid > 0) {
/* We may have children we don't know about:
* sh -c 'sleep 1 & exec xargs ...'
* Do not make G.running_procs go negative.
*/
if (G.running_procs != 0)
G.running_procs--;
status = WIFSIGNALED(wstat)
? 0x180 + WTERMSIG(wstat)
: WEXITSTATUS(wstat);
if (status > 0 && status < 255) {
/* See below why 123 does not abort */
G.xargs_exitcode = 123;
status = 0;
}
if (status == 0)
goto again; /* maybe we have more children? */
/* else: "bad" status, will bail out */
} else if (G.max_procs != 0) {
/* Not in final waitpid() loop,
* and G.running_procs < G.max_procs: start more procs
*/
status = spawn(G.args);
/* here "status" actually holds pid, or -1 */
if (status > 0) {
G.running_procs++;
status = 0;
}
/* else: status == -1 (failed to fork or exec) */
} else {
/* final waitpid() loop: must be ECHILD "no more children" */
status = 0;
}
}
#endif
/* Manpage:
* """xargs exits with the following status:
* 0 if it succeeds
* 123 if any invocation of the command exited with status 1-125
* 124 if the command exited with status 255
* ("""If any invocation of the command exits with a status of 255,
* xargs will stop immediately without reading any further input.
* An error message is issued on stderr when this happens.""")
* 125 if the command is killed by a signal
* 126 if the command cannot be run
* 127 if the command is not found
* 1 if some other error occurred."""
*/
if (status < 0) {
bb_simple_perror_msg(G.args[0]);
status = (errno == ENOENT) ? 127 : 126;
}
else if (status >= 0x180) {
bb_error_msg("'%s' terminated by signal %u",
G.args[0], status - 0x180);
status = 125;
}
else if (status != 0) {
if (status == 255) {
bb_error_msg("%s: exited with status 255; aborting", G.args[0]);
status = 124;
goto ret;
}
/* "123 if any invocation of the command exited with status 1-125"
* This implies that nonzero exit code is remembered,
* but does not cause xargs to stop: we return 0.
*/
G.xargs_exitcode = 123;
status = 0;
}
ret:
if (status != 0)
G.xargs_exitcode = status;
return status;
}
/* In POSIX/C locale isspace is only these chars: "\t\n\v\f\r" and space.
* "\t\n\v\f\r" happen to have ASCII codes 9,10,11,12,13.
*/
#define ISSPACE(a) ({ unsigned char xargs__isspace = (a) - 9; xargs__isspace == (' ' - 9) || xargs__isspace <= (13 - 9); })
static void store_param(char *s)
{
/* Grow by 256 elements at once */
if (!(G.idx & 0xff)) { /* G.idx == N*256? */
/* Enlarge, make G.args[(N+1)*256 - 1] last valid idx */
G.args = xrealloc(G.args, sizeof(G.args[0]) * (G.idx + 0x100));
}
G.args[G.idx++] = s;
}
/* process[0]_stdin:
* Read characters into buf[n_max_chars+1], and when parameter delimiter
* is seen, store the address of a new parameter to args[].
* If reading discovers that last chars do not form the complete
* parameter, the pointer to the first such "tail character" is returned.
* (buf has extra byte at the end to accommodate terminating NUL
* of "tail characters" string).
* Otherwise, the returned pointer points to NUL byte.
* On entry, buf[] may contain some "seed chars" which are to become
* the beginning of the first parameter.
*/
#if ENABLE_FEATURE_XARGS_SUPPORT_QUOTES
static char* FAST_FUNC process_stdin(int n_max_chars, int n_max_arg, char *buf)
{
#define q G.process_stdin__q
#define state G.process_stdin__state
char *s = buf; /* start of the word */
char *p = s + strlen(buf); /* end of the word */
buf += n_max_chars; /* past buffer's end */
/* "goto ret" is used instead of "break" to make control flow
* more obvious: */
while (1) {
int c = getchar();
if (c == EOF) {
if (p != s)
goto close_word;
goto ret;
}
if (state == BACKSLASH) {
state = NORM;
goto set;
}
if (state == QUOTE) {
if (c != q)
goto set;
q = '\0';
state = NORM;
} else { /* if (state == NORM) */
if (ISSPACE(c)) {
if (p != s) {
close_word:
state = SPACE;
c = '\0';
goto set;
}
} else {
if (c == '\\') {
state = BACKSLASH;
} else if (c == '\'' || c == '"') {
q = c;
state = QUOTE;
} else {
set:
*p++ = c;
}
}
}
if (state == SPACE) { /* word's delimiter or EOF detected */
state = NORM;
if (q) {
bb_error_msg_and_die("unmatched %s quote",
q == '\'' ? "single" : "double");
}
/* A full word is loaded */
if (G.eof_str) {
if (strcmp(s, G.eof_str) == 0) {
while (getchar() != EOF)
continue;
p = s;
goto ret;
}
}
store_param(s);
dbg_msg("args[]:'%s'", s);
s = p;
n_max_arg--;
if (n_max_arg == 0) {
goto ret;
}
}
if (p == buf) {
goto ret;
}
}
ret:
*p = '\0';
/* store_param(NULL) - caller will do it */
dbg_msg("return:'%s'", s);
return s;
#undef q
#undef state
}
#else
/* The variant does not support single quotes, double quotes or backslash */
static char* FAST_FUNC process_stdin(int n_max_chars, int n_max_arg, char *buf)
{
char *s = buf; /* start of the word */
char *p = s + strlen(buf); /* end of the word */
buf += n_max_chars; /* past buffer's end */
while (1) {
int c = getchar();
if (c == EOF) {
if (p == s)
goto ret;
}
if (c == EOF || ISSPACE(c)) {
if (p == s)
continue;
c = EOF;
}
*p++ = (c == EOF ? '\0' : c);
if (c == EOF) { /* word's delimiter or EOF detected */
/* A full word is loaded */
if (G.eof_str) {
if (strcmp(s, G.eof_str) == 0) {
while (getchar() != EOF)
continue;
p = s;
goto ret;
}
}
store_param(s);
dbg_msg("args[]:'%s'", s);
s = p;
n_max_arg--;
if (n_max_arg == 0) {
goto ret;
}
}
if (p == buf) {
goto ret;
}
}
ret:
*p = '\0';
/* store_param(NULL) - caller will do it */
dbg_msg("return:'%s'", s);
return s;
}
#endif /* FEATURE_XARGS_SUPPORT_QUOTES */
#if ENABLE_FEATURE_XARGS_SUPPORT_ZERO_TERM
static char* FAST_FUNC process0_stdin(int n_max_chars, int n_max_arg, char *buf)
{
char *s = buf; /* start of the word */
char *p = s + strlen(buf); /* end of the word */
buf += n_max_chars; /* past buffer's end */
while (1) {
int c = getchar();
if (c == EOF) {
if (p == s)
goto ret;
c = '\0';
}
*p++ = c;
if (c == '\0') { /* NUL or EOF detected */
/* A full word is loaded */
store_param(s);
dbg_msg("args[]:'%s'", s);
s = p;
n_max_arg--;
if (n_max_arg == 0) {
goto ret;
}
}
if (p == buf) {
goto ret;
}
}
ret:
*p = '\0';
/* store_param(NULL) - caller will do it */
dbg_msg("return:'%s'", s);
return s;
}
#endif /* FEATURE_XARGS_SUPPORT_ZERO_TERM */
#if ENABLE_FEATURE_XARGS_SUPPORT_REPL_STR
/*
* Used if -I<repl> was specified.
* In this mode, words aren't appended to PROG ARGS.
* Instead, entire input line is read, then <repl> string
* in every PROG and ARG is replaced with the line:
* echo -e "ho ho\nhi" | xargs -I_ cmd __ _
* results in "cmd 'ho hoho ho' 'ho ho'"; "cmd 'hihi' 'hi'".
* -n MAX_ARGS seems to be ignored.
* Tested with GNU findutils 4.5.10.
*/
//FIXME: n_max_chars is not handled the same way as in GNU findutils.
//FIXME: quoting is not implemented.
static char* FAST_FUNC process_stdin_with_replace(int n_max_chars, int n_max_arg UNUSED_PARAM, char *buf)
{
int i;
char *end, *p;
/* Free strings from last invocation, if any */
for (i = 0; G.args && G.args[i]; i++)
if (G.args[i] != G.argv[i])
free(G.args[i]);
end = buf + n_max_chars;
p = buf;
while (1) {
int c = getchar();
if (c == EOF || c == G.eol_ch) {
if (p == buf)
goto ret; /* empty line */
c = '\0';
}
*p++ = c;
if (c == '\0') { /* EOL or EOF detected */
i = 0;
while (G.argv[i]) {
char *arg = G.argv[i];
int count = count_strstr(arg, G.repl_str);
if (count != 0)
arg = xmalloc_substitute_string(arg, count, G.repl_str, buf);
store_param(arg);
dbg_msg("args[]:'%s'", arg);
i++;
}
p = buf;
goto ret;
}
if (p == end) {
goto ret;
}
}
ret:
*p = '\0';
/* store_param(NULL) - caller will do it */
dbg_msg("return:'%s'", buf);
return buf;
}
#endif
#if ENABLE_FEATURE_XARGS_SUPPORT_CONFIRMATION
/* Prompt the user for a response, and
* if user responds affirmatively, return true;
* otherwise, return false. Uses "/dev/tty", not stdin.
*/
static int xargs_ask_confirmation(void)
{
FILE *tty_stream;
int r;
tty_stream = xfopen_for_read(CURRENT_TTY);
fputs(" ?...", stderr);
r = bb_ask_y_confirmation_FILE(tty_stream);
fclose(tty_stream);
return r;
}
#else
# define xargs_ask_confirmation() 1
#endif
//usage:#define xargs_trivial_usage
//usage: "[OPTIONS] [PROG ARGS]"
//usage:#define xargs_full_usage "\n\n"
//usage: "Run PROG on every item given by stdin\n"
//usage: IF_FEATURE_XARGS_SUPPORT_ZERO_TERM(
//usage: "\n -0 Input is separated by NULs"
//usage: )
//usage: IF_FEATURE_XARGS_SUPPORT_ARGS_FILE(
//usage: "\n -a FILE Read from FILE instead of stdin"
//usage: )
//usage: "\n -r Don't run command if input is empty"
//usage: "\n -t Print the command on stderr before execution"
//usage: IF_FEATURE_XARGS_SUPPORT_CONFIRMATION(
//usage: "\n -p Ask user whether to run each command"
//usage: )
//usage: "\n -E STR,-e[STR] STR stops input processing"
//usage: IF_FEATURE_XARGS_SUPPORT_REPL_STR(
//usage: "\n -I STR Replace STR within PROG ARGS with input line"
//usage: )
//usage: "\n -n N Pass no more than N args to PROG"
//usage: "\n -s N Pass command line of no more than N bytes"
//usage: IF_FEATURE_XARGS_SUPPORT_PARALLEL(
//usage: "\n -P N Run up to N PROGs in parallel"
//usage: )
//usage: IF_FEATURE_XARGS_SUPPORT_TERMOPT(
//usage: "\n -x Exit if size is exceeded"
//usage: )
//usage:#define xargs_example_usage
//usage: "$ ls | xargs gzip\n"
//usage: "$ find . -name '*.c' -print | xargs rm\n"
/* Correct regardless of combination of CONFIG_xxx */
enum {
OPTBIT_VERBOSE = 0,
OPTBIT_NO_EMPTY,
OPTBIT_UPTO_NUMBER,
OPTBIT_UPTO_SIZE,
OPTBIT_EOF_STRING,
OPTBIT_EOF_STRING1,
IF_FEATURE_XARGS_SUPPORT_CONFIRMATION(OPTBIT_INTERACTIVE,)
IF_FEATURE_XARGS_SUPPORT_TERMOPT( OPTBIT_TERMINATE ,)
IF_FEATURE_XARGS_SUPPORT_ZERO_TERM( OPTBIT_ZEROTERM ,)
IF_FEATURE_XARGS_SUPPORT_REPL_STR( OPTBIT_REPLSTR ,)
IF_FEATURE_XARGS_SUPPORT_REPL_STR( OPTBIT_REPLSTR1 ,)
OPT_VERBOSE = 1 << OPTBIT_VERBOSE ,
OPT_NO_EMPTY = 1 << OPTBIT_NO_EMPTY ,
OPT_UPTO_NUMBER = 1 << OPTBIT_UPTO_NUMBER,
OPT_UPTO_SIZE = 1 << OPTBIT_UPTO_SIZE ,
OPT_EOF_STRING = 1 << OPTBIT_EOF_STRING , /* GNU: -e[<param>] */
OPT_EOF_STRING1 = 1 << OPTBIT_EOF_STRING1, /* SUS: -E<param> */
OPT_INTERACTIVE = IF_FEATURE_XARGS_SUPPORT_CONFIRMATION((1 << OPTBIT_INTERACTIVE)) + 0,
OPT_TERMINATE = IF_FEATURE_XARGS_SUPPORT_TERMOPT( (1 << OPTBIT_TERMINATE )) + 0,
OPT_ZEROTERM = IF_FEATURE_XARGS_SUPPORT_ZERO_TERM( (1 << OPTBIT_ZEROTERM )) + 0,
OPT_REPLSTR = IF_FEATURE_XARGS_SUPPORT_REPL_STR( (1 << OPTBIT_REPLSTR )) + 0,
OPT_REPLSTR1 = IF_FEATURE_XARGS_SUPPORT_REPL_STR( (1 << OPTBIT_REPLSTR1 )) + 0,
};
#define OPTION_STR "+trn:s:e::E:" \
IF_FEATURE_XARGS_SUPPORT_CONFIRMATION("p") \
IF_FEATURE_XARGS_SUPPORT_TERMOPT( "x") \
IF_FEATURE_XARGS_SUPPORT_ZERO_TERM( "0") \
IF_FEATURE_XARGS_SUPPORT_REPL_STR( "I:i::") \
IF_FEATURE_XARGS_SUPPORT_PARALLEL( "P:+") \
IF_FEATURE_XARGS_SUPPORT_ARGS_FILE( "a:")
int xargs_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int xargs_main(int argc UNUSED_PARAM, char **argv)
{
int initial_idx;
int i;
char *max_args;
char *max_chars;
char *buf;
unsigned opt;
int n_max_chars;
int n_max_arg;
#if ENABLE_FEATURE_XARGS_SUPPORT_ZERO_TERM \
|| ENABLE_FEATURE_XARGS_SUPPORT_REPL_STR
char* FAST_FUNC (*read_args)(int, int, char*) = process_stdin;
#else
#define read_args process_stdin
#endif
IF_FEATURE_XARGS_SUPPORT_ARGS_FILE(char *opt_a = NULL;)
INIT_G();
opt = getopt32long(argv, OPTION_STR,
"no-run-if-empty\0" No_argument "r",
&max_args, &max_chars, &G.eof_str, &G.eof_str
IF_FEATURE_XARGS_SUPPORT_REPL_STR(, &G.repl_str, &G.repl_str)
IF_FEATURE_XARGS_SUPPORT_PARALLEL(, &G.max_procs)
IF_FEATURE_XARGS_SUPPORT_ARGS_FILE(, &opt_a)
);
#if ENABLE_FEATURE_XARGS_SUPPORT_PARALLEL
if (G.max_procs <= 0) /* -P0 means "run lots of them" */
G.max_procs = 100; /* let's not go crazy high */
#endif
#if ENABLE_FEATURE_XARGS_SUPPORT_ARGS_FILE
if (opt_a)
xmove_fd(xopen(opt_a, O_RDONLY), 0);
#endif
/* -E ""? You may wonder why not just omit -E?
* This is used for portability:
* old xargs was using "_" as default for -E / -e */
if ((opt & OPT_EOF_STRING1) && G.eof_str[0] == '\0')
G.eof_str = NULL;
if (opt & OPT_ZEROTERM) {
IF_FEATURE_XARGS_SUPPORT_ZERO_TERM(read_args = process0_stdin;)
IF_FEATURE_XARGS_SUPPORT_REPL_STR(G.eol_ch = '\0';)
}
argv += optind;
//argc -= optind;
if (!argv[0]) {
/* default behavior is to echo all the filenames */
*--argv = (char*)"echo";
//argc++;
}
/*
* The Open Group Base Specifications Issue 6:
* "The xargs utility shall limit the command line length such that
* when the command line is invoked, the combined argument
* and environment lists (see the exec family of functions
* in the System Interfaces volume of IEEE Std 1003.1-2001)
* shall not exceed {ARG_MAX}-2048 bytes".
*/
n_max_chars = bb_arg_max();
if (n_max_chars > 32 * 1024)
n_max_chars = 32 * 1024;
/*
* POSIX suggests substracting 2048 bytes from sysconf(_SC_ARG_MAX)
* so that the process may safely modify its environment.
*/
n_max_chars -= 2048;
if (opt & OPT_UPTO_SIZE) {
n_max_chars = xatou_range(max_chars, 1, INT_MAX);
}
/* Account for prepended fixed arguments */
{
size_t n_chars = 0;
for (i = 0; argv[i]; i++) {
n_chars += strlen(argv[i]) + 1;
}
n_max_chars -= n_chars;
}
/* Sanity check */
if (n_max_chars <= 0) {
bb_simple_error_msg_and_die("can't fit single argument within argument list size limit");
}
buf = xzalloc(n_max_chars + 1);
n_max_arg = n_max_chars;
if (opt & OPT_UPTO_NUMBER) {
n_max_arg = xatou_range(max_args, 1, INT_MAX);
/* Not necessary, we use growable args[]: */
/* if (n_max_arg > n_max_chars) n_max_arg = n_max_chars */
}
#if ENABLE_FEATURE_XARGS_SUPPORT_REPL_STR
if (opt & (OPT_REPLSTR | OPT_REPLSTR1)) {
/*
* -I<str>:
* Unmodified args are kept in G.argv[i],
* G.args[i] receives malloced G.argv[i] with <str> replaced
* with input line. Setting this up:
*/
G.args = NULL;
G.argv = argv;
read_args = process_stdin_with_replace;
/* Make -I imply -r. GNU findutils seems to do the same: */
/* (otherwise "echo -n | xargs -I% echo %" would SEGV) */
opt |= OPT_NO_EMPTY;
} else
#endif
{
/* Store the command to be executed, part 1.
* We can statically allocate (argc + n_max_arg + 1) elements
* and do not bother with resizing args[], but on 64-bit machines
* this results in args[] vector which is ~8 times bigger
* than n_max_chars! That is, with n_max_chars == 20k,
* args[] will take 160k (!), which will most likely be
* almost entirely unused.
*/
for (i = 0; argv[i]; i++)
store_param(argv[i]);
}
initial_idx = G.idx;
while (1) {
char *rem;
G.idx = initial_idx;
rem = read_args(n_max_chars, n_max_arg, buf);
store_param(NULL);
if (!G.args[initial_idx]) { /* not even one ARG was added? */
if (*rem != '\0')
bb_simple_error_msg_and_die("argument line too long");
if (opt & OPT_NO_EMPTY)
break;
}
opt |= OPT_NO_EMPTY;
if (opt & (OPT_INTERACTIVE | OPT_VERBOSE)) {
const char *fmt = " %s" + 1;
char **args = G.args;
for (i = 0; args[i]; i++) {
fprintf(stderr, fmt, args[i]);
fmt = " %s";
}
if (!(opt & OPT_INTERACTIVE))
bb_putchar_stderr('\n');
}
if (!(opt & OPT_INTERACTIVE) || xargs_ask_confirmation()) {
if (xargs_exec() != 0)
break; /* G.xargs_exitcode is set by xargs_exec() */
}
overlapping_strcpy(buf, rem);
} /* while */
if (ENABLE_FEATURE_CLEAN_UP) {
free(G.args);
free(buf);
}
#if ENABLE_FEATURE_XARGS_SUPPORT_PARALLEL
G.max_procs = 0;
xargs_exec(); /* final waitpid() loop */
#endif
return G.xargs_exitcode;
}
#ifdef TEST
const char *applet_name = "debug stuff usage";
void bb_show_usage(void)
{
fprintf(stderr, "Usage: %s [-p] [-r] [-t] -[x] [-n max_arg] [-s max_chars]\n",
applet_name);
exit(EXIT_FAILURE);
}
int main(int argc, char **argv)
{
return xargs_main(argc, argv);
}
#endif /* TEST */