/*
* Mini xargs implementation for busybox
+ * Options are supported: "-prtx -n max_arg -s max_chars -e[ouf_str]"
*
- * Copyright (C) 2000 by Lineo, inc.
- * Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>
- * Remixed by Mark Whitley <markw@lineo.com>, <markw@enol.com>
+ * (C) 2002,2003 by Vladimir Oleynik <dzo@simtreas.ru>
+ *
+ * Special thanks
+ * - Mark Whitley and Glenn McGrath for stimul to rewrote :)
+ * - 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
*
*/
-#include "busybox.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
+#include <unistd.h>
+#include <getopt.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#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
+
+
+#ifdef TEST
+# ifndef CONFIG_FEATURE_XARGS_SUPPORT_CONFIRMATION
+# define CONFIG_FEATURE_XARGS_SUPPORT_CONFIRMATION
+# endif
+# ifndef CONFIG_FEATURE_XARGS_SUPPORT_QUOTES
+# define CONFIG_FEATURE_XARGS_SUPPORT_QUOTES
+# endif
+# ifndef CONFIG_FEATURE_XARGS_SUPPORT_TERMOPT
+# define CONFIG_FEATURE_XARGS_SUPPORT_TERMOPT
+# endif
+# ifndef CONFIG_FEATURE_XARGS_SUPPORT_ZERO_TERM
+# define CONFIG_FEATURE_XARGS_SUPPORT_ZERO_TERM
+# endif
+#endif
+
+/*
+ This function have special algorithm.
+ Don`t use fork and include to main!
+*/
+static int xargs_exec(char *const *args)
+{
+ pid_t p;
+ volatile int exec_errno = 0; /* shared vfork stack */
+
+ if ((p = vfork()) >= 0) {
+ if (p == 0) {
+ /* vfork -- child */
+ execvp(args[0], args);
+ exec_errno = errno; /* set error to shared stack */
+ _exit(1);
+ } else {
+ /* vfork -- parent */
+ int status;
+
+ 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;
+ } else {
+ if (WEXITSTATUS(status) == 255) {
+ bb_error_msg("%s: exited with status 255; aborting",
+ args[0]);
+ return 124;
+ }
+ if (WIFSTOPPED(status)) {
+ bb_error_msg("%s: stopped by signal %d", args[0],
+ WSTOPSIG(status));
+ return 125;
+ }
+ if (WIFSIGNALED(status)) {
+ bb_error_msg("%s: terminated by signal %d", args[0],
+ WTERMSIG(status));
+ return 125;
+ }
+ if (WEXITSTATUS(status) != 0)
+ return 123;
+ return 0;
+ }
+ }
+ } else {
+ bb_perror_msg_and_die("vfork");
+ }
+}
+
+
+typedef struct xlist_s {
+ char *data;
+ size_t lenght;
+ struct xlist_s *link;
+} xlist_t;
+
+static int eof_stdin_detected;
+
+#define ISBLANK(c) ((c) == ' ' || (c) == '\t')
+#define ISSPACE(c) (ISBLANK (c) || (c) == '\n' || (c) == '\r' \
+ || (c) == '\f' || (c) == '\v')
+
+#ifdef CONFIG_FEATURE_XARGS_SUPPORT_QUOTES
+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 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;
+ }
+
+ while (!eof_stdin_detected) {
+ c = getchar();
+ if (c == EOF) {
+ eof_stdin_detected++;
+ if (s)
+ goto unexpected_eof;
+ break;
+ }
+ if (eof_str_detected)
+ continue;
+ if (state == BACKSLASH) {
+ state = NORM;
+ goto set;
+ } else if (state == QUOTE) {
+ if (c == q) {
+ q = 0;
+ state = NORM;
+ } else {
+ goto set;
+ }
+ } else { /* if(state == NORM) */
+
+ if (ISSPACE(c)) {
+ if (s) {
+ unexpected_eof:
+ state = SPACE;
+ 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 ((p - buf) >= mc)
+ bb_error_msg_and_die("argument line too long");
+ *p++ = c;
+ }
+ }
+ }
+ if (state == SPACE) { /* word's delimiter or EOF detected */
+ if (q)
+ 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;
+ }
+ }
+ s = NULL;
+ state = NORM;
+ }
+ }
+ return list_arg;
+}
+#else
+/* The variant is unsupport single, double quotes and backslash */
+static xlist_t *process_stdin(xlist_t * list_arg, const char *eof_str,
+ size_t mc, char *buf)
+{
+
+ 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;
+ }
+
+ while (!eof_stdin_detected) {
+ c = getchar();
+ if (c == EOF) {
+ eof_stdin_detected++;
+ }
+ if (eof_str_detected)
+ continue;
+ if (c == EOF || ISSPACE(c)) {
+ if (s == NULL)
+ 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;
+ 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;
+ }
+ prev = cur;
+ line_l += lenght;
+ if (line_l > mc) {
+ /* stop memory usage :-) */
+ break;
+ }
+ s = NULL;
+ }
+ }
+ }
+ return list_arg;
+}
+#endif /* CONFIG_FEATURE_XARGS_SUPPORT_QUOTES */
+
+
+#ifdef CONFIG_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. */
+static int xargs_ask_confirmation(void)
+{
+ static FILE *tty_stream;
+ int c, savec;
+
+ if (!tty_stream) {
+ tty_stream = fopen("/dev/tty", "r");
+ if (!tty_stream)
+ bb_perror_msg_and_die("/dev/tty");
+ /* pranoidal security by vodz */
+ fcntl(fileno(tty_stream), F_SETFD, FD_CLOEXEC);
+ }
+ fputs(" ?...", stderr);
+ fflush(stderr);
+ c = savec = getc(tty_stream);
+ while (c != EOF && c != '\n')
+ c = getc(tty_stream);
+ if (savec == 'y' || savec == 'Y')
+ return 1;
+ return 0;
+}
+
+# define OPT_INC_P 1
+#else
+# define OPT_INC_P 0
+# define xargs_ask_confirmation() 1
+#endif /* CONFIG_FEATURE_XARGS_SUPPORT_CONFIRMATION */
+
+#ifdef CONFIG_FEATURE_XARGS_SUPPORT_TERMOPT
+# define OPT_INC_X 1
+#else
+# define OPT_INC_X 0
+#endif
+
+#ifdef CONFIG_FEATURE_XARGS_SUPPORT_ZERO_TERM
+static xlist_t *process0_stdin(xlist_t * list_arg, const char *eof_str,
+ 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;
+ }
+
+ 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 ((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;
+}
+
+# define READ_ARGS(l, e, nmc, mc) (*read_args)(l, e, nmc, mc)
+# define OPT_INC_0 1 /* future use */
+#else
+# define OPT_INC_0 0 /* future use */
+# define READ_ARGS(l, e, nmc, mc) process_stdin(l, e, nmc, mc)
+#endif /* CONFIG_FEATURE_XARGS_SUPPORT_ZERO_TERM */
+
+
+#define OPT_VERBOSE (1<<0)
+#define OPT_NO_EMPTY (1<<1)
+#define OPT_UPTO_NUMBER (1<<2)
+#define OPT_UPTO_SIZE (1<<3)
+#define OPT_EOF_STRING (1<<4)
+#ifdef CONFIG_FEATURE_XARGS_SUPPORT_CONFIRMATION
+#define OPT_INTERACTIVE (1<<5)
+#else
+#define OPT_INTERACTIVE (0) /* require for algorithm &| */
+#endif
+#define OPT_TERMINATE (1<<(5+OPT_INC_P))
+#define OPT_ZEROTERM (1<<(5+OPT_INC_P+OPT_INC_X))
+/* next future
+#define OPT_NEXT_OTHER (1<<(5+OPT_INC_P+OPT_INC_X+OPT_INC_0))
+*/
int xargs_main(int argc, char **argv)
{
- char *cmd_to_be_executed = NULL;
- char *file_to_act_on = NULL;
-
- /*
- * No options are supported in this version of xargs; no getopt.
- *
- * Re: The missing -t flag: Most programs that produce output also print
- * the filename, so xargs doesn't really need to do it again. Supporting
- * the -t flag =greatly= bloats up the size of this app and the memory it
- * uses because you have to buffer all the input file strings in memory. If
- * you really want to see the filenames that xargs will act on, just run it
- * once with no args and xargs will echo the filename. Simple.
- */
-
- /* Store the command to be executed (taken from the command line) */
- if (argc == 1) {
+ char **args;
+ int i, a, n;
+ xlist_t *list = NULL;
+ xlist_t *cur;
+ 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 = "_";
+ unsigned long opt;
+ size_t n_max_chars;
+
+#ifdef CONFIG_FEATURE_XARGS_SUPPORT_ZERO_TERM
+ xlist_t *(*read_args) (xlist_t *, const char *, size_t, char *) =
+ process_stdin;
+#endif
+
+#ifdef CONFIG_FEATURE_XARGS_SUPPORT_CONFIRMATION
+ bb_opt_complementaly = "pt";
+#endif
+
+ opt = bb_getopt_ulflags(argc, argv, "+trn:s:e::"
+#ifdef CONFIG_FEATURE_XARGS_SUPPORT_CONFIRMATION
+ "p"
+#endif
+#ifdef CONFIG_FEATURE_XARGS_SUPPORT_TERMOPT
+ "x"
+#endif
+#ifdef CONFIG_FEATURE_XARGS_SUPPORT_ZERO_TERM
+ "0"
+#endif
+ , &max_args, &max_chars, &eof_str);
+
+ a = argc - optind;
+ argv += optind;
+ if (a == 0) {
/* default behavior is to echo all the filenames */
- cmd_to_be_executed = strdup("/bin/echo ");
- } else {
- /* concatenate all the arguments passed to xargs together */
- int i;
- int len = 1; /* for the '\0' */
- for (i = 1; i < argc; i++) {
- len += strlen(argv[i]);
- len += 1; /* for the space between the args */
- cmd_to_be_executed = xrealloc(cmd_to_be_executed, len);
- strcat(cmd_to_be_executed, argv[i]);
- strcat(cmd_to_be_executed, " ");
+ *argv = "echo";
+ a++;
+ }
+
+ orig_arg_max = ARG_MAX;
+ if (orig_arg_max == -1)
+ orig_arg_max = LONG_MAX;
+ orig_arg_max -= 2048; /* POSIX.2 requires subtracting 2048. */
+ if ((opt & OPT_UPTO_SIZE)) {
+ n_max_chars = bb_xgetularg10_bnd(max_chars, 1, orig_arg_max);
+ for (i = 0; i < a; 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 -= 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);
- /* Now, read in one line at a time from stdin, and store this
- * line to be used later as an argument to the command */
- while ((file_to_act_on = get_line_from_file(stdin)) !=NULL) {
+ if ((opt & OPT_UPTO_NUMBER)) {
+ n_max_arg = bb_xgetularg10_bnd(max_args, 1, INT_MAX);
+ } else {
+ n_max_arg = n_max_chars;
+ }
- FILE *cmd_output = NULL;
- char *output_line = NULL;
- char *execstr = NULL;
+#ifdef CONFIG_FEATURE_XARGS_SUPPORT_ZERO_TERM
+ if (opt & OPT_ZEROTERM)
+ read_args = process0_stdin;
+#endif
- /* eat the newline off the filename. */
- if (file_to_act_on[strlen(file_to_act_on)-1] == '\n')
- file_to_act_on[strlen(file_to_act_on)-1] = '\0';
+ while ((list = READ_ARGS(list, eof_str, n_max_chars, max_chars)) != NULL
+ || (opt & OPT_NO_EMPTY) == 0) {
+ 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");
+ 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 */
- /* eat blank lines */
- if (strlen(file_to_act_on) == 0)
- continue;
+ /* allocating pointers for execvp:
+ a*arg, n*arg from stdin, NULL */
+ args = xcalloc(n + a + 1, sizeof(char *));
- /* assemble the command and execute it */
- execstr = xcalloc(strlen(cmd_to_be_executed) +
- strlen(file_to_act_on) + 1, sizeof(char));
- strcat(execstr, cmd_to_be_executed);
- strcat(execstr, file_to_act_on);
- cmd_output = popen(execstr, "r");
- if (cmd_output == NULL) {
- perror("popen");
- exit(1);
+ /* Store the command to be executed
+ (taken from the command line) */
+ for (i = 0; i < a; i++)
+ args[i] = argv[i];
+ /* (taken from stdin) */
+ for (cur = list; n; cur = cur->link) {
+ args[i++] = cur->data;
+ n--;
}
- /* harvest the output */
- while ((output_line = get_line_from_file(cmd_output)) != NULL) {
- fputs(output_line, stdout);
- free(output_line);
+ if ((opt & (OPT_INTERACTIVE | OPT_VERBOSE))) {
+ for (i = 0; args[i]; i++) {
+ if (i)
+ fputc(' ', stderr);
+ fputs(args[i], stderr);
+ }
+ if ((opt & OPT_INTERACTIVE) == 0)
+ fputc('\n', stderr);
+ }
+ if ((opt & OPT_INTERACTIVE) == 0 || xargs_ask_confirmation() != 0) {
+ child_error = xargs_exec(args);
}
/* clean up */
- pclose(cmd_output);
- free(execstr);
- free(file_to_act_on);
+ for (i = a; args[i]; i++) {
+ cur = list;
+ list = list->link;
+ free(cur);
+ }
+ free(args);
+ if (child_error > 0 && child_error != 123) {
+ break;
+ }
}
-
-#ifdef BB_FEATURE_CLEAN_UP
- free(cmd_to_be_executed);
+#ifdef CONFIG_FEATURE_CLEAN_UP
+ free(max_chars);
#endif
+ return child_error;
+}
- return 0;
+
+#ifdef TEST
+
+const char *bb_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",
+ bb_applet_name);
+ exit(1);
}
-/* vi: set sw=4 ts=4: */
+int main(int argc, char **argv)
+{
+ return xargs_main(argc, argv);
+}
+#endif /* TEST */
projects / oweals / busybox.git / blobdiff