/* vi: set sw=4 ts=4: */
/*
* Mini xargs implementation for busybox
- * Options are supported: "-prtx -n max_arg -s max_chars -e[ouf_str]"
*
* (C) 2002,2003 by Vladimir Oleynik <dzo@simtreas.ru>
*
* - Mike Rendell <michael@cs.mun.ca>
* and David MacKenzie <djm@gnu.ai.mit.edu>.
*
- * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
+ * 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
- *
*/
-#include "busybox.h"
-
-/* 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)
-#endif
-#ifndef ARG_MAX
-#define ARG_MAX 470
-#endif
+//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.
+
+//applet:IF_XARGS(APPLET_NOEXEC(xargs, xargs, BB_DIR_USR_BIN, BB_SUID_DROP, xargs))
+
+//kbuild:lib-$(CONFIG_XARGS) += xargs.o
+
+#include "libbb.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 CONFIG_FEATURE_XARGS_SUPPORT_CONFIRMATION
-# define CONFIG_FEATURE_XARGS_SUPPORT_CONFIRMATION
+# ifndef ENABLE_FEATURE_XARGS_SUPPORT_CONFIRMATION
+# define ENABLE_FEATURE_XARGS_SUPPORT_CONFIRMATION 1
# endif
-# ifndef CONFIG_FEATURE_XARGS_SUPPORT_QUOTES
-# define CONFIG_FEATURE_XARGS_SUPPORT_QUOTES
+# ifndef ENABLE_FEATURE_XARGS_SUPPORT_QUOTES
+# define ENABLE_FEATURE_XARGS_SUPPORT_QUOTES 1
# endif
-# ifndef CONFIG_FEATURE_XARGS_SUPPORT_TERMOPT
-# define CONFIG_FEATURE_XARGS_SUPPORT_TERMOPT
+# ifndef ENABLE_FEATURE_XARGS_SUPPORT_TERMOPT
+# define ENABLE_FEATURE_XARGS_SUPPORT_TERMOPT 1
# endif
-# ifndef CONFIG_FEATURE_XARGS_SUPPORT_ZERO_TERM
-# define CONFIG_FEATURE_XARGS_SUPPORT_ZERO_TERM
+# ifndef ENABLE_FEATURE_XARGS_SUPPORT_ZERO_TERM
+# define ENABLE_FEATURE_XARGS_SUPPORT_ZERO_TERM 1
# endif
#endif
+
+struct globals {
+ char **args;
+ const char *eof_str;
+ int idx;
+} FIX_ALIASING;
+#define G (*(struct globals*)&bb_common_bufsiz1)
+#define INIT_G() do { \
+ G.eof_str = NULL; /* need to clear by hand because we are NOEXEC applet */ \
+} while (0)
+
+
/*
- This function has special algorithm.
- Don't use fork and include to main!
-*/
-static int xargs_exec(char *const *args)
+ * This function has special algorithm.
+ * Don't use fork and include to main!
+ */
+static int xargs_exec(void)
{
- pid_t p;
- volatile int exec_errno = 0; /* shared vfork stack */
int status;
- p = vfork();
- if (p < 0)
- bb_perror_msg_and_die("vfork");
-
- if (p == 0) {
- /* vfork -- child */
- execvp(args[0], args);
- exec_errno = errno; /* set error to shared stack */
- _exit(1);
- }
-
- /* vfork -- parent */
- while (wait(&status) == (pid_t) -1)
- if (errno != EINTR)
- break;
- if (exec_errno) {
- errno = exec_errno;
- bb_perror_msg("%s", args[0]);
- return exec_errno == ENOENT ? 127 : 126;
+ status = spawn_and_wait(G.args);
+ if (status < 0) {
+ bb_simple_perror_msg(G.args[0]);
+ return errno == ENOENT ? 127 : 126;
}
- if (WEXITSTATUS(status) == 255) {
- bb_error_msg("%s: exited with status 255; aborting", args[0]);
+ if (status == 255) {
+ bb_error_msg("%s: exited with status 255; aborting", G.args[0]);
return 124;
}
- if (WIFSTOPPED(status)) {
- bb_error_msg("%s: stopped by signal %d",
- args[0], WSTOPSIG(status));
- return 125;
- }
- if (WIFSIGNALED(status)) {
+ if (status >= 0x180) {
bb_error_msg("%s: terminated by signal %d",
- args[0], WTERMSIG(status));
+ G.args[0], status - 0x180);
return 125;
}
- if (WEXITSTATUS(status))
+ if (status)
return 123;
return 0;
}
+/* 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); })
-typedef struct xlist_s {
- char *data;
- size_t lenght;
- struct xlist_s *link;
-} xlist_t;
-
-static int eof_stdin_detected;
+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;
+}
-#define ISBLANK(c) ((c) == ' ' || (c) == '\t')
-#define ISSPACE(c) (ISBLANK(c) || (c) == '\n' || (c) == '\r' \
- || (c) == '\f' || (c) == '\v')
+/* 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 accomodate 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.
+ */
-#ifdef CONFIG_FEATURE_XARGS_SUPPORT_QUOTES
-static xlist_t *process_stdin(xlist_t * list_arg,
- const char *eof_str, size_t mc, char *buf)
+#if ENABLE_FEATURE_XARGS_SUPPORT_QUOTES
+static char* FAST_FUNC process_stdin(int n_max_chars, int n_max_arg, 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 q = 0; /* quote char */
+ 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 */
- xlist_t *cur;
- xlist_t *prev;
-
- for (prev = cur = list_arg; cur; cur = cur->link) {
- line_l += cur->lenght; /* previous allocated */
- if (prev != cur)
- prev = prev->link;
- }
+ char *s = buf; /* start of the word */
+ char *p = s + strlen(buf); /* end of the word */
- while (!eof_stdin_detected) {
- c = getchar();
+ 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) {
- eof_stdin_detected++;
- if (s)
- goto unexpected_eof;
- break;
+ if (p != s)
+ goto close_word;
+ goto ret;
}
- if (eof_str_detected)
- continue;
if (state == BACKSLASH) {
state = NORM;
goto set;
- } else if (state == QUOTE) {
- if (c == q) {
- q = 0;
- state = NORM;
- } else {
+ }
+ if (state == QUOTE) {
+ if (c != q)
goto set;
- }
- } else { /* if(state == NORM) */
-
+ q = '\0';
+ state = NORM;
+ } else { /* if (state == NORM) */
if (ISSPACE(c)) {
- if (s) {
-unexpected_eof:
+ if (p != s) {
+ close_word:
state = SPACE;
- c = 0;
+ c = '\0';
goto set;
}
} else {
- if (s == NULL)
- s = p = buf;
if (c == '\\') {
state = BACKSLASH;
} else if (c == '\'' || c == '"') {
q = c;
state = QUOTE;
} else {
-set:
- if ((size_t)(p - buf) >= mc)
- bb_error_msg_and_die("argument line too long");
+ set:
*p++ = c;
}
}
bb_error_msg_and_die("unmatched %s quote",
q == '\'' ? "single" : "double");
}
- /* word loaded */
- if (eof_str) {
- eof_str_detected = strcmp(s, eof_str) == 0;
- }
- if (!eof_str_detected) {
- size_t lenght = (p - buf);
-
- cur = xmalloc(sizeof(xlist_t) + lenght);
- cur->data = memcpy(cur + 1, s, lenght);
- cur->lenght = lenght;
- cur->link = NULL;
- if (prev == NULL) {
- list_arg = cur;
- } else {
- prev->link = cur;
- }
- prev = cur;
- line_l += lenght;
- if (line_l > mc) {
- /* stop memory usage :-) */
- break;
+ /* A full word is loaded */
+ if (G.eof_str) {
+ if (strcmp(s, G.eof_str) == 0) {
+ while (getchar() != EOF)
+ continue;
+ p = s;
+ goto ret;
}
}
- s = NULL;
+ store_param(s);
+ dbg_msg("args[]:'%s'", s);
+ s = p;
+ n_max_arg--;
+ if (n_max_arg == 0) {
+ goto ret;
+ }
state = NORM;
}
+ if (p == buf) {
+ goto ret;
+ }
}
- return list_arg;
+ ret:
+ *p = '\0';
+ /* store_param(NULL) - caller will do it */
+ dbg_msg("return:'%s'", s);
+ return s;
}
#else
/* The variant does not support single quotes, double quotes or backslash */
-static xlist_t *process_stdin(xlist_t * list_arg,
- const char *eof_str, size_t mc, char *buf)
+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 */
- int c; /* current char */
- int 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 */
- xlist_t *cur;
- xlist_t *prev;
-
- for (prev = cur = list_arg; cur; cur = cur->link) {
- line_l += cur->lenght; /* previous allocated */
- if (prev != cur)
- prev = prev->link;
- }
+ buf += n_max_chars; /* past buffer's end */
- while (!eof_stdin_detected) {
- c = getchar();
+ while (1) {
+ int c = getchar();
if (c == EOF) {
- eof_stdin_detected++;
+ if (p == s)
+ goto ret;
}
- if (eof_str_detected)
- continue;
if (c == EOF || ISSPACE(c)) {
- if (s == NULL)
+ if (p == s)
continue;
c = EOF;
}
- if (s == NULL)
- s = p = buf;
- if ((p - buf) >= mc)
- bb_error_msg_and_die("argument line too long");
- *p++ = c == EOF ? 0 : c;
+ *p++ = (c == EOF ? '\0' : c);
if (c == EOF) { /* word's delimiter or EOF detected */
- /* word loaded */
- if (eof_str) {
- eof_str_detected = strcmp(s, eof_str) == 0;
- }
- if (!eof_str_detected) {
- size_t lenght = (p - buf);
-
- cur = xmalloc(sizeof(xlist_t) + lenght);
- cur->data = memcpy(cur + 1, s, lenght);
- cur->lenght = lenght;
- cur->link = NULL;
- if (prev == NULL) {
- list_arg = cur;
- } else {
- prev->link = cur;
+ /* A full word is loaded */
+ if (G.eof_str) {
+ if (strcmp(s, G.eof_str) == 0) {
+ while (getchar() != EOF)
+ continue;
+ p = s;
+ goto ret;
}
- prev = cur;
- line_l += lenght;
- if (line_l > mc) {
- /* stop memory usage :-) */
- break;
- }
- s = NULL;
}
+ 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;
}
}
- return list_arg;
+ ret:
+ *p = '\0';
+ /* store_param(NULL) - caller will do it */
+ dbg_msg("return:'%s'", s);
+ return s;
}
-#endif /* CONFIG_FEATURE_XARGS_SUPPORT_QUOTES */
+#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') { /* word's delimiter 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 */
-#ifdef CONFIG_FEATURE_XARGS_SUPPORT_CONFIRMATION
+#if ENABLE_FEATURE_XARGS_SUPPORT_CONFIRMATION
/* Prompt the user for a response, and
if the user responds affirmatively, return true;
- otherwise, return false. Used "/dev/tty", not stdin. */
+ otherwise, return false. Uses "/dev/tty", not stdin. */
static int xargs_ask_confirmation(void)
{
- static FILE *tty_stream;
+ FILE *tty_stream;
int c, savec;
- if (!tty_stream) {
- tty_stream = xfopen(CURRENT_TTY, "r");
- /* pranoidal security by vodz */
- fcntl(fileno(tty_stream), F_SETFD, FD_CLOEXEC);
- }
+ 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);
- if (savec == 'y' || savec == 'Y')
- return 1;
- return 0;
+ fclose(tty_stream);
+ return (savec == 'y' || savec == 'Y');
}
#else
# define xargs_ask_confirmation() 1
-#endif /* CONFIG_FEATURE_XARGS_SUPPORT_CONFIRMATION */
-
-#ifdef CONFIG_FEATURE_XARGS_SUPPORT_ZERO_TERM
-static xlist_t *process0_stdin(xlist_t * list_arg, const char *eof_str ATTRIBUTE_UNUSED,
- 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 */
- xlist_t *cur;
- xlist_t *prev;
-
- for (prev = cur = list_arg; cur; cur = cur->link) {
- line_l += cur->lenght; /* previous allocated */
- if (prev != cur)
- prev = prev->link;
- }
+#endif
- while (!eof_stdin_detected) {
- c = getchar();
- if (c == EOF) {
- eof_stdin_detected++;
- if (s == NULL)
- break;
- c = 0;
- }
- if (s == NULL)
- s = p = buf;
- if ((size_t)(p - buf) >= mc)
- bb_error_msg_and_die("argument line too long");
- *p++ = c;
- if (c == 0) { /* word's delimiter or EOF detected */
- /* word loaded */
- size_t lenght = (p - buf);
-
- cur = xmalloc(sizeof(xlist_t) + lenght);
- cur->data = memcpy(cur + 1, s, lenght);
- cur->lenght = lenght;
- cur->link = NULL;
- if (prev == NULL) {
- list_arg = cur;
- } else {
- prev->link = cur;
- }
- prev = cur;
- line_l += lenght;
- if (line_l > mc) {
- /* stop memory usage :-) */
- break;
- }
- s = NULL;
- }
- }
- return list_arg;
-}
-#endif /* CONFIG_FEATURE_XARGS_SUPPORT_ZERO_TERM */
+//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_CONFIRMATION(
+//usage: "\n -p Ask user whether to run each command"
+//usage: )
+//usage: "\n -r Don't run command if input is empty"
+//usage: IF_FEATURE_XARGS_SUPPORT_ZERO_TERM(
+//usage: "\n -0 Input is separated by NUL characters"
+//usage: )
+//usage: "\n -t Print the command on stderr before execution"
+//usage: "\n -e[STR] STR stops input processing"
+//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_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_UPTO_NUMBER,
OPTBIT_UPTO_SIZE,
OPTBIT_EOF_STRING,
- USE_FEATURE_XARGS_SUPPORT_CONFIRMATION(OPTBIT_INTERACTIVE,)
- USE_FEATURE_XARGS_SUPPORT_TERMOPT( OPTBIT_TERMINATE ,)
- USE_FEATURE_XARGS_SUPPORT_ZERO_TERM( OPTBIT_ZEROTERM ,)
-
- 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 ,
- 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,
+ 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 ,)
+
+ 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,
};
-#define OPTION_STR "+trn:s:e::" \
- USE_FEATURE_XARGS_SUPPORT_CONFIRMATION("p") \
- USE_FEATURE_XARGS_SUPPORT_TERMOPT( "x") \
- USE_FEATURE_XARGS_SUPPORT_ZERO_TERM( "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")
+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 i;
int child_error = 0;
- char *max_args, *max_chars;
- int n_max_arg;
- size_t n_chars = 0;
- long orig_arg_max;
- const char *eof_str = "_";
+ char *max_args;
+ char *max_chars;
+ char *buf;
unsigned opt;
- size_t n_max_chars;
+ int n_max_chars;
+ int n_max_arg;
#if ENABLE_FEATURE_XARGS_SUPPORT_ZERO_TERM
- xlist_t* (*read_args)(xlist_t*, const char*, size_t, char*) = process_stdin;
+ char* FAST_FUNC (*read_args)(int, int, char*) = process_stdin;
#else
#define read_args process_stdin
#endif
- opt = getopt32(argc, argv, OPTION_STR, &max_args, &max_chars, &eof_str);
+ INIT_G();
+
+#if ENABLE_DESKTOP && ENABLE_LONG_OPTS
+ /* For example, Fedora's build system uses --no-run-if-empty */
+ applet_long_options =
+ "no-run-if-empty\0" No_argument "r"
+ ;
+#endif
+ opt = getopt32(argv, OPTION_STR, &max_args, &max_chars, &G.eof_str, &G.eof_str);
+
+ /* -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)
- USE_FEATURE_XARGS_SUPPORT_ZERO_TERM(read_args = process0_stdin);
+ IF_FEATURE_XARGS_SUPPORT_ZERO_TERM(read_args = process0_stdin);
- argc -= optind;
argv += optind;
- if (!argc) {
+ argc -= optind;
+ if (!argv[0]) {
/* default behavior is to echo all the filenames */
- *argv = "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 */
-
+ /* -s NUM default. fileutils-4.4.2 uses 128k, but I heasitate
+ * to use such a big value - first need to change code to use
+ * growable buffer instead of fixed one.
+ */
+ n_max_chars = 32 * 1024;
+ /* Make smaller if system does not allow our default value.
+ * 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".
+ */
+ {
+ long arg_max = 0;
+#if defined _SC_ARG_MAX
+ arg_max = sysconf(_SC_ARG_MAX) - 2048;
+#elif defined ARG_MAX
+ arg_max = ARG_MAX - 2048;
+#endif
+ if (arg_max > 0 && n_max_chars > arg_max)
+ n_max_chars = arg_max;
+ }
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("can not fit single argument within argument list size limit");
+ 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;
- } 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;
}
- max_chars = xmalloc(n_max_chars);
+ /* Sanity check */
+ if (n_max_chars <= 0) {
+ bb_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 = xatoul_range(max_args, 1, INT_MAX);
- } else {
- n_max_arg = n_max_chars;
+ 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 */
}
- while ((list = read_args(list, eof_str, n_max_chars, max_chars)) != NULL ||
- !(opt & OPT_NO_EMPTY))
- {
- opt |= OPT_NO_EMPTY;
- n = 0;
- n_chars = 0;
-#ifdef CONFIG_FEATURE_XARGS_SUPPORT_TERMOPT
- for (cur = list; cur;) {
- n_chars += cur->lenght;
- n++;
- cur = cur->link;
- if (n_chars > n_max_chars || (n == n_max_arg && cur)) {
- if (opt & OPT_TERMINATE)
- bb_error_msg_and_die("argument list too long");
+ /* Allocate pointers for execvp */
+ /* 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.
+ */
+ /* See store_param() for matching 256-step growth logic */
+ G.args = xmalloc(sizeof(G.args[0]) * ((argc + 0xff) & ~0xff));
+
+ /* Store the command to be executed, part 1 */
+ for (i = 0; argv[i]; i++)
+ G.args[i] = argv[i];
+
+ while (1) {
+ char *rem;
+
+ G.idx = argc;
+ rem = read_args(n_max_chars, n_max_arg, buf);
+ store_param(NULL);
+
+ if (!G.args[argc]) {
+ if (*rem != '\0')
+ bb_error_msg_and_die("argument line too long");
+ if (opt & OPT_NO_EMPTY)
break;
- }
- }
-#else
- for (cur = list; cur; cur = cur->link) {
- n_chars += cur->lenght;
- n++;
- if (n_chars > n_max_chars || n == n_max_arg) {
- break;
- }
- }
-#endif /* CONFIG_FEATURE_XARGS_SUPPORT_TERMOPT */
-
- /* allocate pointers for execvp:
- argc*arg, n*arg from stdin, NULL */
- args = xzalloc((n + argc + 1) * sizeof(char *));
-
- /* store the command to be executed
- (taken from the command line) */
- for (i = 0; i < argc; i++)
- args[i] = argv[i];
- /* (taken from stdin) */
- for (cur = list; n; cur = cur->link) {
- args[i++] = cur->data;
- n--;
}
+ 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++) {
- if (i)
- fputc(' ', stderr);
- fputs(args[i], stderr);
+ fprintf(stderr, fmt, args[i]);
+ fmt = " %s";
}
if (!(opt & OPT_INTERACTIVE))
- fputc('\n', stderr);
+ bb_putchar_stderr('\n');
}
+
if (!(opt & OPT_INTERACTIVE) || xargs_ask_confirmation()) {
- child_error = xargs_exec(args);
+ child_error = xargs_exec();
}
- /* clean up */
- for (i = argc; args[i]; i++) {
- cur = list;
- list = list->link;
- free(cur);
- }
- free(args);
if (child_error > 0 && child_error != 123) {
break;
}
+
+ overlapping_strcpy(buf, rem);
+ } /* while */
+
+ if (ENABLE_FEATURE_CLEAN_UP) {
+ free(G.args);
+ free(buf);
}
- if (ENABLE_FEATURE_CLEAN_UP) free(max_chars);
+
return child_error;
}
{
fprintf(stderr, "Usage: %s [-p] [-r] [-t] -[x] [-n max_arg] [-s max_chars]\n",
applet_name);
- exit(1);
+ exit(EXIT_FAILURE);
}
int main(int argc, char **argv)
projects / platform / upstream / busybox.git / blobdiff