1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
|
/*
* Mini xargs implementation for busybox
*
* Copyright (C) 1999,2000,2001 by Lineo, inc.
* Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>
* Remixed by Mark Whitley <markw@lineo.com>, <markw@codepoet.org>
*
* 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
*
*/
#include "busybox.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
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) {
/* 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, " ");
}
}
/* 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) {
FILE *cmd_output = NULL;
char *output_line = NULL;
char *execstr = NULL;
/* 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';
/* eat blank lines */
if (strlen(file_to_act_on) == 0)
continue;
/* 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_msg_and_die("popen");
/* harvest the output */
while ((output_line = get_line_from_file(cmd_output)) != NULL) {
fputs(output_line, stdout);
free(output_line);
}
/* clean up */
pclose(cmd_output);
free(execstr);
free(file_to_act_on);
}
#ifdef BB_FEATURE_CLEAN_UP
free(cmd_to_be_executed);
#endif
return 0;
}
/* vi: set sw=4 ts=4: */
|
