*
*/
+//kbuild:lib-$(CONFIG_XARGS) += xargs.o
+//config:
+//config:config XARGS
+//config: bool "xargs"
+//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.
+
#include "libbb.h"
/* This is a NOEXEC applet. Be very careful! */
/* COMPAT: SYSV version defaults size (and has a max value of) to 470.
We try to make it as large as possible. */
#if !defined(ARG_MAX) && defined(_SC_ARG_MAX)
-#define ARG_MAX sysconf (_SC_ARG_MAX)
+# define ARG_MAX sysconf(_SC_ARG_MAX)
#endif
-#ifndef ARG_MAX
-#define ARG_MAX 470
+#if !defined(ARG_MAX)
+# define ARG_MAX 470
#endif
bb_error_msg("%s: exited with status 255; aborting", args[0]);
return 124;
}
-/* Huh? I think we won't see this, ever. We don't wait with WUNTRACED!
- if (WIFSTOPPED(status)) {
- bb_error_msg("%s: stopped by signal %d",
- args[0], WSTOPSIG(status));
- return 125;
- }
-*/
- if (status >= 1000) {
+ if (status >= 0x180) {
bb_error_msg("%s: terminated by signal %d",
- args[0], status - 1000);
+ args[0], status - 0x180);
return 125;
}
if (status)
char xstr[1];
} xlist_t;
-static smallint eof_stdin_detected;
-
-#define ISBLANK(c) ((c) == ' ' || (c) == '\t')
-#define ISSPACE(c) (ISBLANK(c) || (c) == '\n' || (c) == '\r' \
- || (c) == '\f' || (c) == '\v')
+/* 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); })
#if ENABLE_FEATURE_XARGS_SUPPORT_QUOTES
-static xlist_t *process_stdin(xlist_t *list_arg,
+static xlist_t* process_stdin(xlist_t *list_arg,
const char *eof_str, size_t mc, char *buf)
{
#define NORM 0
#define QUOTE 1
#define BACKSLASH 2
#define SPACE 4
-
- char *s = NULL; /* start word */
- char *p = NULL; /* pointer to end word */
+ char *s = NULL; /* start of the word */
+ char *p = NULL; /* pointer to end of the word */
char q = '\0'; /* quote char */
char state = NORM;
char eof_str_detected = 0;
- size_t line_l = 0; /* size loaded args line */
- int c; /* current char */
+ size_t line_l = 0; /* size of loaded args */
xlist_t *cur;
xlist_t *prev;
prev = cur = list_arg;
- while (1) {
- if (!cur) break;
+ while (cur) {
prev = cur;
line_l += cur->length;
cur = cur->link;
}
- while (!eof_stdin_detected) {
- c = getchar();
+ while (1) {
+ int c = getchar();
if (c == EOF) {
- eof_stdin_detected = 1;
if (s)
goto unexpected_eof;
break;
}
- if (eof_str_detected)
+ if (eof_str_detected) /* skip till EOF */
continue;
if (state == BACKSLASH) {
state = NORM;
goto set;
- } else if (state == QUOTE) {
+ }
+ if (state == QUOTE) {
if (c != q)
goto set;
q = '\0';
bb_error_msg_and_die("unmatched %s quote",
q == '\'' ? "single" : "double");
}
- /* word loaded */
+ /* A full word is loaded */
if (eof_str) {
eof_str_detected = (strcmp(s, eof_str) == 0);
}
}
prev = cur;
line_l += length;
- if (line_l > mc) {
- /* stop memory usage :-) */
+ if (line_l > mc) /* limit stop memory usage */
break;
- }
}
s = NULL;
state = NORM;
}
#else
/* The variant does not support single quotes, double quotes or backslash */
-static xlist_t *process_stdin(xlist_t *list_arg,
+static xlist_t* process_stdin(xlist_t *list_arg,
const char *eof_str, size_t mc, char *buf)
{
-
- int c; /* current char */
char eof_str_detected = 0;
- char *s = NULL; /* start word */
- char *p = NULL; /* pointer to end word */
- size_t line_l = 0; /* size loaded args line */
+ char *s = NULL; /* start of the word */
+ char *p = NULL; /* pointer to end of the word */
+ size_t line_l = 0; /* size of loaded args */
xlist_t *cur;
xlist_t *prev;
prev = cur = list_arg;
- while (1) {
- if (!cur) break;
+ while (cur) {
prev = cur;
line_l += cur->length;
cur = cur->link;
}
- while (!eof_stdin_detected) {
- c = getchar();
+ while (1) {
+ int c = getchar();
if (c == EOF) {
- eof_stdin_detected = 1;
+ if (s == NULL)
+ break;
}
- if (eof_str_detected)
+ if (eof_str_detected) { /* skip till EOF */
continue;
+ }
if (c == EOF || ISSPACE(c)) {
if (s == NULL)
continue;
bb_error_msg_and_die("argument line too long");
*p++ = (c == EOF ? '\0' : c);
if (c == EOF) { /* word's delimiter or EOF detected */
- /* word loaded */
+ /* A full word is loaded */
if (eof_str) {
eof_str_detected = (strcmp(s, eof_str) == 0);
}
}
prev = cur;
line_l += length;
- if (line_l > mc) {
- /* stop memory usage :-) */
+ if (line_l > mc) /* limit stop memory usage */
break;
- }
- s = NULL;
}
+ s = NULL;
}
}
return list_arg;
tty_stream = xfopen_for_read(CURRENT_TTY);
fputs(" ?...", stderr);
- fflush(stderr);
+ fflush_all();
c = savec = getc(tty_stream);
while (c != EOF && c != '\n')
c = getc(tty_stream);
#endif /* FEATURE_XARGS_SUPPORT_CONFIRMATION */
#if ENABLE_FEATURE_XARGS_SUPPORT_ZERO_TERM
-static xlist_t *process0_stdin(xlist_t *list_arg,
+static xlist_t* process0_stdin(xlist_t *list_arg,
const char *eof_str UNUSED_PARAM, size_t mc, char *buf)
{
- int c; /* current char */
- char *s = NULL; /* start word */
- char *p = NULL; /* pointer to end word */
- size_t line_l = 0; /* size loaded args line */
+ char *s = NULL; /* start of the word */
+ char *p = NULL; /* pointer to end of the word */
+ size_t line_l = 0; /* size of loaded args */
xlist_t *cur;
xlist_t *prev;
prev = cur = list_arg;
- while (1) {
- if (!cur) break;
+ while (cur) {
prev = cur;
line_l += cur->length;
cur = cur->link;
}
- while (!eof_stdin_detected) {
- c = getchar();
+ while (1) {
+ int c = getchar();
if (c == EOF) {
- eof_stdin_detected = 1;
if (s == NULL)
break;
c = '\0';
bb_error_msg_and_die("argument line too long");
*p++ = c;
if (c == '\0') { /* word's delimiter or EOF detected */
- /* word loaded */
+ /* A full word is loaded */
size_t length = (p - buf);
/* Dont xzalloc - it can be quite big */
cur = xmalloc(offsetof(xlist_t, xstr) + length);
}
prev = cur;
line_l += length;
- if (line_l > mc) {
- /* stop memory usage :-) */
+ if (line_l > mc) /* limit stop memory usage */
break;
- }
s = NULL;
}
}
OPTBIT_UPTO_SIZE,
OPTBIT_EOF_STRING,
OPTBIT_EOF_STRING1,
- USE_FEATURE_XARGS_SUPPORT_CONFIRMATION(OPTBIT_INTERACTIVE,)
- USE_FEATURE_XARGS_SUPPORT_TERMOPT( OPTBIT_TERMINATE ,)
- USE_FEATURE_XARGS_SUPPORT_ZERO_TERM( OPTBIT_ZEROTERM ,)
+ IF_FEATURE_XARGS_SUPPORT_CONFIRMATION(OPTBIT_INTERACTIVE,)
+ IF_FEATURE_XARGS_SUPPORT_TERMOPT( OPTBIT_TERMINATE ,)
+ IF_FEATURE_XARGS_SUPPORT_ZERO_TERM( OPTBIT_ZEROTERM ,)
OPT_VERBOSE = 1 << OPTBIT_VERBOSE ,
OPT_NO_EMPTY = 1 << OPTBIT_NO_EMPTY ,
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 = USE_FEATURE_XARGS_SUPPORT_CONFIRMATION((1 << OPTBIT_INTERACTIVE)) + 0,
- OPT_TERMINATE = USE_FEATURE_XARGS_SUPPORT_TERMOPT( (1 << OPTBIT_TERMINATE )) + 0,
- OPT_ZEROTERM = USE_FEATURE_XARGS_SUPPORT_ZERO_TERM( (1 << OPTBIT_ZEROTERM )) + 0,
+ 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,
};
#define OPTION_STR "+trn:s:e::E:" \
- USE_FEATURE_XARGS_SUPPORT_CONFIRMATION("p") \
- USE_FEATURE_XARGS_SUPPORT_TERMOPT( "x") \
- USE_FEATURE_XARGS_SUPPORT_ZERO_TERM( "0")
+ IF_FEATURE_XARGS_SUPPORT_CONFIRMATION("p") \
+ IF_FEATURE_XARGS_SUPPORT_TERMOPT( "x") \
+ IF_FEATURE_XARGS_SUPPORT_ZERO_TERM( "0")
int xargs_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int xargs_main(int argc, char **argv)
{
- char **args;
- int i, n;
xlist_t *list = NULL;
- xlist_t *cur;
int child_error = 0;
- char *max_args, *max_chars;
+ char *max_args;
+ char *max_chars;
+ char *buf;
int n_max_arg;
- size_t n_chars = 0;
- long orig_arg_max;
const char *eof_str = NULL;
unsigned opt;
size_t n_max_chars;
eof_str = NULL;
if (opt & OPT_ZEROTERM)
- USE_FEATURE_XARGS_SUPPORT_ZERO_TERM(read_args = process0_stdin);
+ IF_FEATURE_XARGS_SUPPORT_ZERO_TERM(read_args = process0_stdin);
argv += optind;
argc -= optind;
- if (!argc) {
+ if (!argv[0]) {
/* default behavior is to echo all the filenames */
- *argv = (char*)"echo";
+ *--argv = (char*)"echo";
argc++;
}
- orig_arg_max = ARG_MAX;
- if (orig_arg_max == -1)
- orig_arg_max = LONG_MAX;
- orig_arg_max -= 2048; /* POSIX.2 requires subtracting 2048 */
+ /* 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 = ARG_MAX; /* might be calling sysconf(_SC_ARG_MAX) */
+ if (n_max_chars < 4*1024); /* paranoia */
+ n_max_chars = 4*1024;
+ n_max_chars -= 2048;
+ /* Sanity check for systems with huge ARG_MAX defines (e.g., Suns which
+ * have it at 1 meg). Things will work fine with a large ARG_MAX
+ * but it will probably hurt the system more than it needs to;
+ * an array of this size is allocated.
+ */
+ if (n_max_chars > 20 * 1024)
+ n_max_chars = 20 * 1024;
if (opt & OPT_UPTO_SIZE) {
- n_max_chars = xatoul_range(max_chars, 1, orig_arg_max);
- for (i = 0; i < argc; i++) {
- n_chars += strlen(*argv) + 1;
- }
- if (n_max_chars < n_chars) {
- bb_error_msg_and_die("cannot fit single argument within argument list size limit");
+ int i;
+ size_t n_chars = 0;
+ n_max_chars = xatoul_range(max_chars, 1, n_max_chars);
+ for (i = 0; argv[i]; i++) {
+ n_chars += strlen(argv[i]) + 1;
}
n_max_chars -= n_chars;
- } else {
- /* Sanity check for systems with huge ARG_MAX defines (e.g., Suns which
- have it at 1 meg). Things will work fine with a large ARG_MAX but it
- will probably hurt the system more than it needs to; an array of this
- size is allocated. */
- if (orig_arg_max > 20 * 1024)
- orig_arg_max = 20 * 1024;
- n_max_chars = orig_arg_max;
+ if ((ssize_t)n_max_chars <= 0) {
+ bb_error_msg_and_die("can't fit single argument within argument list size limit");
+ }
}
- max_chars = xmalloc(n_max_chars);
+
+ buf = xmalloc(n_max_chars);
if (opt & OPT_UPTO_NUMBER) {
n_max_arg = xatoul_range(max_args, 1, INT_MAX);
n_max_arg = n_max_chars;
}
- while ((list = read_args(list, eof_str, n_max_chars, max_chars)) != NULL ||
- !(opt & OPT_NO_EMPTY))
- {
+ while ((list = read_args(list, eof_str, n_max_chars, buf)) != NULL
+ || !(opt & OPT_NO_EMPTY)
+ ) {
+ char **args;
+ xlist_t *cur;
+ int i, n;
+ size_t n_chars = 0;
+
opt |= OPT_NO_EMPTY;
n = 0;
- n_chars = 0;
#if ENABLE_FEATURE_XARGS_SUPPORT_TERMOPT
for (cur = list; cur;) {
n_chars += cur->length;
break;
}
}
-#endif /* FEATURE_XARGS_SUPPORT_TERMOPT */
+#endif
- /* allocate pointers for execvp:
- argc*arg, n*arg from stdin, NULL */
- args = xzalloc((n + argc + 1) * sizeof(char *));
+ /* allocate pointers for execvp */
+ args = xzalloc(sizeof(args[0]) * (argc + n + 1));
/* store the command to be executed
- (taken from the command line) */
- for (i = 0; i < argc; i++)
+ * (taken from the command line) */
+ for (i = 0; argv[i]; i++)
args[i] = argv[i];
/* (taken from stdin) */
for (cur = list; n; cur = cur->link) {
if (opt & (OPT_INTERACTIVE | OPT_VERBOSE)) {
for (i = 0; args[i]; i++) {
if (i)
- fputc(' ', stderr);
+ bb_putchar_stderr(' ');
fputs(args[i], stderr);
}
if (!(opt & OPT_INTERACTIVE))
- fputc('\n', stderr);
+ bb_putchar_stderr('\n');
}
+
if (!(opt & OPT_INTERACTIVE) || xargs_ask_confirmation()) {
child_error = xargs_exec(args);
}
free(cur);
}
free(args);
+
if (child_error > 0 && child_error != 123) {
break;
}
} /* while */
+
if (ENABLE_FEATURE_CLEAN_UP)
- free(max_chars);
+ free(buf);
+
return child_error;
}
projects / oweals / busybox.git / blobdiff