-/* vi: set sw=4 ts=4: */
/*
* Mini xargs implementation for busybox
*
* 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>
*
* 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 <stdlib.h>
#include <stdio.h>
+#include <stdlib.h>
#include <string.h>
-#include <errno.h>
-#include <getopt.h>
-#include <ctype.h>
-#include <sys/types.h>
-#include <sys/wait.h>
-
int xargs_main(int argc, char **argv)
{
- char *in_from_stdin = NULL;
- char *args = NULL;
char *cmd_to_be_executed = NULL;
- char traceflag = 0;
- int len_args=0, len_cmd_to_be_executed, opt;
- pid_t pid;
- int wpid, status;
-
- /* Note that we do not use getopt here, since
- * we only want to interpret initial options,
- * not options passed to commands */
- while (--argc && **(++argv) == '-') {
- while (*++(*argv)) {
- switch (**argv) {
- case 't':
- traceflag=1;
- break;
- default:
- fatalError(xargs_usage);
- }
- }
- }
+ 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 == 0) {
- len_cmd_to_be_executed=6;
- cmd_to_be_executed = xmalloc(len_cmd_to_be_executed);
- strcat(cmd_to_be_executed, "echo");
+ if (argc == 1) {
+ /* default behavior is to echo all the filenames */
+ cmd_to_be_executed = strdup("/bin/echo ");
} else {
- opt=strlen(*argv);
- len_cmd_to_be_executed = (opt > 10)? opt : 10;
- cmd_to_be_executed = xcalloc(len_cmd_to_be_executed, sizeof(char));
- strcat(cmd_to_be_executed, *argv);
+ /* 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, " ");
+ }
}
- //args=xrealloc(args, len_args);
-// strcpy(args, " ");
-
/* Now, read in one line at a time from stdin, and store this
* line to be used later as an argument to the command */
- in_from_stdin = get_line_from_file(stdin);
- for (;in_from_stdin!=NULL;) {
- char *tmp;
- opt = strlen(in_from_stdin);
- len_args += opt + 3;
- args=xrealloc(args, len_args);
-
- /* Strip out the final \n */
- in_from_stdin[opt-1]=' ';
-
- /* Replace any tabs with spaces */
- while( (tmp = strchr(in_from_stdin, '\t')) != NULL )
- *tmp=' ';
-
- /* Strip out any extra intra-word spaces */
- while( (tmp = strstr(in_from_stdin, " ")) != NULL ) {
- opt = strlen(in_from_stdin);
- memmove(tmp, tmp+1, opt-(tmp-in_from_stdin));
+ 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("popen");
+ exit(1);
}
- /* trim trailing whitespace */
- opt = strlen(in_from_stdin) - 1;
- while (isspace(in_from_stdin[opt]))
- opt--;
- in_from_stdin[++opt] = 0;
-
- /* Strip out any leading whitespace */
- tmp=in_from_stdin;
- while(isspace(*tmp))
- tmp++;
-
- strcat(args, tmp);
- strcat(args, " ");
-
- free(in_from_stdin);
- in_from_stdin = get_line_from_file(stdin);
- }
-
- if ((pid = fork()) == 0) {
- char *cmd[255];
- int i=1;
-
- if (traceflag==1) {
- fprintf(stderr, "%s ", cmd_to_be_executed);
+ /* harvest the output */
+ while ((output_line = get_line_from_file(cmd_output)) != NULL) {
+ fputs(output_line, stdout);
+ free(output_line);
}
- cmd[0] = cmd_to_be_executed;
- while (--argc && ++argv && *argv ) {
- if (traceflag==1) {
- fprintf(stderr, "%s ", *argv);
- }
- cmd[i++]=*argv;
- }
- if (traceflag==1) {
- fprintf(stderr, "%s\n", args);
- }
- cmd[i++] = args;
- cmd[i] = NULL;
- execvp(cmd_to_be_executed, cmd);
- /* What? Still here? Exit with an error */
- fatalError("%s: %s\n", cmd_to_be_executed, strerror(errno));
+ /* clean up */
+ pclose(cmd_output);
+ free(execstr);
+ free(file_to_act_on);
}
- /* Wait for a child process to exit */
- wpid = wait(&status);
-
#ifdef BB_FEATURE_CLEAN_UP
- free(args);
free(cmd_to_be_executed);
#endif
- if (wpid > 0)
- return (WEXITSTATUS(status));
- else
- return EXIT_FAILURE;
+ return 0;
}
-/*
-Local Variables:
-c-file-style: "linux"
-c-basic-offset: 4
-tab-width: 4
-End:
-*/
+
+/* vi: set sw=4 ts=4: */
projects / oweals / busybox.git / blobdiff