Fix another build failure found with randconfig
[oweals/busybox.git] / findutils / xargs.c
index 27f83350f3bc5cfdaf9ce7bc4e86cdc6731b4c4f..0d1bb43fc89a7e05ee06627342762f0149c1b0d2 100644 (file)
+/* vi: set sw=4 ts=4: */
 /*
  * Mini xargs implementation for busybox
- * Only "-prt" options are supported in this version of xargs.
  *
- * (C) 2002 by Vladimir Oleynik <dzo@simtreas.ru>
- * (C) 2003 by Glenn McGrath <bug1@optushome.com.au>
+ * (C) 2002,2003 by Vladimir Oleynik <dzo@simtreas.ru>
  *
- * Special thanks Mark Whitley for stimul to rewrote :)
+ * 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>.
  *
- * This program 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 2 of the License, or
- * (at your option) any later version.
- *
- * This program 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 this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
- *
- * Reference:
- *     http://www.opengroup.org/onlinepubs/007904975/utilities/xargs.html
- *
- *
- * BUGS:
- *     p option doesnt accept user input, should read input from /dev/tty
- *
- *     E option doesnt allow spaces before argument
- *
- *     xargs should terminate if an invocation of a constructed command line
- *  returns an exit status of 255.
- *
- *  exit value of isnt correct 
- *
- *  doesnt print quoted string properly
+ * 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 <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-#include <getopt.h>
-#include <errno.h>
-#include <sys/types.h>
-#include <sys/wait.h>
-#include "busybox.h"
+//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 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;
+       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 have special algorithm.
  Don`t use fork and include to main!
-*/
-static void xargs_exec(char * const * args)
* This function has special algorithm.
* Don't use fork and include to main!
+ */
+static int xargs_exec(void)
 {
-       int p;
-       int common[4];  /* shared vfork stack */
-
-       common[0] = 0;
-       if ((p = vfork()) >= 0) {
-               if (p == 0) {
-                       /* vfork -- child */
-                       execvp(args[0], args);
-                       common[0] = errno; /* set error to shared stack */
-                       _exit(1);
-               } else {
-                       /* vfork -- parent */
-                       wait(NULL);
-                       if(common[0]) {
-                               errno = common[0];
-                               bb_perror_msg_and_die("%s", args[0]);
+       int status;
+
+       status = spawn_and_wait(G.args);
+       if (status < 0) {
+               bb_simple_perror_msg(G.args[0]);
+               return errno == ENOENT ? 127 : 126;
+       }
+       if (status == 255) {
+               bb_error_msg("%s: exited with status 255; aborting", G.args[0]);
+               return 124;
+       }
+       if (status >= 0x180) {
+               bb_error_msg("%s: terminated by signal %d",
+                       G.args[0], status - 0x180);
+               return 125;
+       }
+       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); })
+
+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 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.
+ */
+
+#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 q = '\0';             /* quote char */
+       char state = NORM;
+       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;
+                               }
                        }
                }
-       } else {
-               bb_perror_msg_and_die("vfork");
+               if (state == SPACE) {   /* word's delimiter or EOF detected */
+                       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;
+                       }
+                       state = NORM;
+               }
+               if (p == buf) {
+                       goto ret;
+               }
        }
+ 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 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 */
 
-#define OPT_VERBOSE    0x2
-#define OPT_INTERACTIVE        0x4
-#define OPT_TERMINATE  0x8
-#define OPT_UPTO_NUMBER        0x10
-#define OPT_UPTO_SIZE  0x20
-#define OPT_EOF_STRING 0x40
+       buf += n_max_chars;        /* past buffer's end */
 
-int xargs_main(int argc, char **argv)
+       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_max_args = NULL;
-       char *s_line_size = NULL;
-       unsigned long flg;
+       char *s = buf;             /* start of the word */
+       char *p = s + strlen(buf); /* end of the word */
 
-       char *eof_string = "_";
-       int line_size = LINE_MAX;
-       unsigned int max_args = LINE_MAX / 2;
+       buf += n_max_chars;        /* past buffer's end */
 
-       char *line_buffer = NULL;
-       char *line_buffer_ptr_ptr;
-       char *old_arg = NULL;
+       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 */
 
-       char **args;
-       char *args_entry_ptr;
+#if ENABLE_FEATURE_XARGS_SUPPORT_CONFIRMATION
+/* Prompt the user for a response, and
+   if the user responds affirmatively, return true;
+   otherwise, return false. Uses "/dev/tty", not stdin. */
+static int xargs_ask_confirmation(void)
+{
+       FILE *tty_stream;
+       int c, savec;
+
+       tty_stream = xfopen_for_read(CURRENT_TTY);
+       fputs(" ?...", stderr);
+       fflush_all();
+       c = savec = getc(tty_stream);
+       while (c != EOF && c != '\n')
+               c = getc(tty_stream);
+       fclose(tty_stream);
+       return (savec == 'y' || savec == 'Y');
+}
+#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_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_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   ,)
+
+       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::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)
+{
        int i;
-       int a;
+       int child_error = 0;
+       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
+       char* FAST_FUNC (*read_args)(int, int, char*) = process_stdin;
+#else
+#define read_args process_stdin
+#endif
+
+       INIT_G();
 
-       
-       bb_opt_complementaly = "pt";
+#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);
 
-       flg = bb_getopt_ulflags(argc, argv, "+tpxn:s:E::", &s_max_args, &s_line_size, &eof_string);
+       /* -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 (s_max_args) {
-               max_args = bb_xgetularg10(s_max_args);
-       }
-       if (s_line_size) {
-               line_size = bb_xgetularg10(s_line_size);
-       }
+       if (opt & OPT_ZEROTERM)
+               IF_FEATURE_XARGS_SUPPORT_ZERO_TERM(read_args = process0_stdin);
 
-       a = argc - optind;
        argv += optind;
-       if(a==0) {
+       argc -= optind;
+       if (!argv[0]) {
                /* default behavior is to echo all the filenames */
-               *argv = "echo";
-               a++;
+               *--argv = (char*)"echo";
+               argc++;
        }
-       /* allocating pointers for execvp: a*arg, arg from stdin, NULL */
-       args = xcalloc(a + 2, sizeof(char *));
 
-       /* Store the command to be executed (taken from the command line) */
-       for (i = 0; i < a; i++) {
-               line_size -= strlen(*argv) + 1;
-               args[i] = *argv++;
+       /* -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 (line_size < 1) {
-               bb_error_msg_and_die("can not fit single argument within argument list size limit");
+       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_error_msg_and_die("can't fit single argument within argument list size limit");
        }
 
-       args[i] = xmalloc(line_size);
-       args_entry_ptr = args[i];
-
-       /* Now, read in one line at a time from stdin, and store this 
-        * line to be used later as an argument to the command */
-       do {
-               char *line_buffer_ptr = NULL;
-               unsigned int arg_count = 0;
-               unsigned int arg_size = 0;
-
-               *args_entry_ptr = '\0';
-
-               /* Get the required number of entries from stdin */
-               do {
-                       /* (Re)fill the line buffer */
-                       if (line_buffer == NULL) {
-                               line_buffer = bb_get_chomped_line_from_file(stdin);
-                               if (line_buffer == NULL) {
-                                       /* EOF, exit outer loop */
-                                       break;
-                               }
-                               line_buffer_ptr = strtok_r(line_buffer, " \t", &line_buffer_ptr_ptr);
-                       } else {
-                               if (old_arg) {
-                                       line_buffer_ptr = old_arg;
-                                       old_arg = NULL;
-                               } else {
-                                       line_buffer_ptr = strtok_r(NULL, " \t", &line_buffer_ptr_ptr);
-                               }
-                       }
-                       /* If no arguments left go back and get another line */
-                       if (line_buffer_ptr == NULL) {
-                               free(line_buffer);
-                               line_buffer = NULL;
-                               continue;
-                       }
+       buf = xzalloc(n_max_chars + 1);
 
-                       if (eof_string && (strcmp(line_buffer_ptr, eof_string) == 0)) {
-                               /* logical EOF, exit outer loop */
-                               line_buffer = NULL;
-                               break;
-                       }
+       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 */
+       }
 
-                       /* Check the next argument will fit */
-                       arg_size += 1 + strlen(line_buffer_ptr);
-                       if (arg_size > line_size) {
-                               if ((arg_count == 0) || ((flg & OPT_TERMINATE) && (arg_count != max_args))){
-                                       bb_error_msg_and_die("argument line too long");
-                               }
-                               old_arg = line_buffer_ptr;
-                               break;
-                       }
+       /* 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));
 
-                       /* Add the entry to our pre-allocated space */
-                       strcat(args_entry_ptr, line_buffer_ptr);
-                       strcat(args_entry_ptr, " ");
-                       arg_count++;
-               } while (arg_count < max_args);
-
-               if (*args_entry_ptr != '\0') {
-                       if(flg & (OPT_VERBOSE | OPT_INTERACTIVE)) {
-                               for(i=0; args[i]; i++) {
-                                       if(i)
-                                               fputc(' ', stderr);
-                                       fputs(args[i], stderr);
-                               }
+       /* Store the command to be executed, part 1 */
+       for (i = 0; argv[i]; i++)
+               G.args[i] = argv[i];
 
-                               fputs(((flg & OPT_INTERACTIVE) ? " ?..." : "\n"), stderr);
-                       }
+       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;
+               }
+               opt |= OPT_NO_EMPTY;
 
-                       if((flg & OPT_INTERACTIVE) == 0 || bb_ask_confirmation() != 0 ) {
-                               xargs_exec(args);
+               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');
                }
-       } while (line_buffer);
 
-#ifdef CONFIG_FEATURE_CLEAN_UP
-       free(args);
-#endif
-       return 0;
+               if (!(opt & OPT_INTERACTIVE) || xargs_ask_confirmation()) {
+                       child_error = xargs_exec();
+               }
+
+               if (child_error > 0 && child_error != 123) {
+                       break;
+               }
+
+               overlapping_strcpy(buf, rem);
+       } /* while */
+
+       if (ENABLE_FEATURE_CLEAN_UP) {
+               free(G.args);
+               free(buf);
+       }
+
+       return child_error;
+}
+
+
+#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 */