From f57674e9a9b0b29102981e1694b76170b78dfb43 Mon Sep 17 00:00:00 2001 From: Glenn L McGrath Date: Sun, 10 Nov 2002 21:47:17 +0000 Subject: [PATCH] Rewrite of xargs by Vladimir N. Oleynik --- AUTHORS | 5 +- docs/busybox_footer.pod | 4 +- findutils/xargs.c | 148 +++++++++++++++++++++++----------------- include/usage.h | 8 ++- 4 files changed, 96 insertions(+), 69 deletions(-) diff --git a/AUTHORS b/AUTHORS index b6dadf44a..6cd8ab80f 100644 --- a/AUTHORS +++ b/AUTHORS @@ -55,7 +55,7 @@ Glenn McGrath ar, dpkg, dpkg-deb Vladimir Oleynik - cmdedit; ports: ash, crond, stty, traceroute, telnetd, top; + cmdedit; xargs(current); ports: ash, crond, stty, traceroute, telnetd, top; locale, various fixes and irreconcilable critic of everything not perfect. @@ -81,7 +81,8 @@ Linus Torvalds mkswap, fsck.minix, mkfs.minix Mark Whitley - grep, sed, cut, xargs, style-guide, new-applet-HOWTO, bug fixes, etc. + grep, sed, cut, xargs(previous), + style-guide, new-applet-HOWTO, bug fixes, etc. Charles P. Wright gzip, mini-netcat(nc) diff --git a/docs/busybox_footer.pod b/docs/busybox_footer.pod index 96d074f7f..1506768c4 100644 --- a/docs/busybox_footer.pod +++ b/docs/busybox_footer.pod @@ -113,7 +113,7 @@ Glenn McGrath Vladimir Oleynik - cmdedit; ports: ash, crond, stty, traceroute, telnetd, top; + cmdedit, xargs(current); ports: ash, crond, stty, traceroute, telnetd, top; locale, various fixes and irreconcilable critic of everything not perfect. @@ -167,4 +167,4 @@ Enrique Zanardi =cut -# $Id: busybox_footer.pod,v 1.7 2002/10/22 12:24:56 andersen Exp $ +# $Id: busybox_footer.pod,v 1.8 2002/11/10 21:47:15 bug1 Exp $ diff --git a/findutils/xargs.c b/findutils/xargs.c index 471bae45b..677618dc0 100644 --- a/findutils/xargs.c +++ b/findutils/xargs.c @@ -1,9 +1,10 @@ /* * Mini xargs implementation for busybox + * Only "-prt" options are supported in this version of xargs. * - * Copyright (C) 1999,2000 by Lineo, inc. and Erik Andersen - * Copyright (C) 1999,2000,2001 by Erik Andersen - * Remixed by Mark Whitley + * (C) 2002 by Vladimir Oleynik + * + * Special thanks Mark Whitley for stimul to rewrote :) * * 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 @@ -23,84 +24,105 @@ #include #include -#include +#include +#include +#include +#include +#include #include "busybox.h" + +/* + This function have special algorithm. + Don`t use fork and include to main! +*/ +static void xargs_exec(char * const * args) +{ + 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]; + perror_msg_and_die("%s", args[0]); + } + } + } else { + perror_msg_and_die("vfork"); + } +} + int xargs_main(int argc, char **argv) { - char *cmd_to_be_executed; char *file_to_act_on; - int i; - int len; + char **args; + int i, a; + char flg_vi = 0; /* verbose |& interactive */ + char flg_no_empty = 0; - /* - * 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. - */ - - argv++; - len = argc; /* arg = count for ' ' + trailing '\0' */ - /* Store the command to be executed (taken from the command line) */ - if (argc == 1) { - /* default behavior is to echo all the filenames */ - argv[0] = "/bin/echo"; - len++; /* space for trailing '\0' */ - } else { - argc--; + while ((a = getopt(argc, argv, "prt")) > 0) { + switch(a) { + case 'p': + flg_vi |= 3; + break; + case 't': + flg_vi |= 1; + break; + case 'r': + flg_no_empty = 1; + break; + default: + show_usage(); } - /* concatenate all the arguments passed to xargs together */ - for (i = 0; i < argc; i++) - len += strlen(argv[i]); - cmd_to_be_executed = xmalloc (len); - for (i = len = 0; i < argc; i++) { - len = sprintf(cmd_to_be_executed + len, "%s ", argv[i]); } + a = argc - optind; + argv += optind; + if(a==0) { + /* default behavior is to echo all the filenames */ + *argv = "/bin/echo"; + a++; + } + /* allocating pointers for execvp: a*arg, arg from stdin, NULL */ + args = xcalloc(a + 3, sizeof(char *)); + + /* Store the command to be executed (taken from the command line) */ + for (i = 0; i < a; i++) + args[i] = *argv++; + /* 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; - char *output_line; - char *execstr; - + while ((file_to_act_on = get_line_from_file(stdin)) != NULL) { /* eat the newline off the filename. */ chomp(file_to_act_on); - - /* eat blank lines */ - if (file_to_act_on[0] == 0) - continue; - - /* assemble the command and execute it */ - bb_asprintf(&execstr, "%s%s", cmd_to_be_executed, 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); + if(file_to_act_on[0] != 0 || flg_no_empty == 0) { + args[a] = file_to_act_on[0] ? file_to_act_on : NULL; + if(flg_vi) { + for(i=0; args[i]; i++) { + if(i) + fputc(' ', stderr); + fputs(args[i], stderr); + } + fprintf(stderr, "%s", ((flg_vi & 2) ? " ?..." : "\n")); + } + if((flg_vi & 2) == 0 || ask_confirmation() != 0 ) { + xargs_exec(args); + } } - /* clean up */ - pclose(cmd_output); - free(execstr); free(file_to_act_on); } - #ifdef CONFIG_FEATURE_CLEAN_UP - free(cmd_to_be_executed); + free(args); #endif - return 0; } - -/* vi: set sw=4 ts=4: */ diff --git a/include/usage.h b/include/usage.h index d0aa3243f..c140a88ba 100644 --- a/include/usage.h +++ b/include/usage.h @@ -2243,9 +2243,13 @@ "Prints the user name associated with the current effective user id." #define xargs_trivial_usage \ - "[COMMAND] [ARGS...]" + "[COMMAND] [-prt] [ARGS...]" #define xargs_full_usage \ - "Executes COMMAND on every item given by standard input." + "Executes COMMAND on every item given by standard input.\n\n" \ + "Options:\n" \ + "\t-p\tPrompt the user about whether to run each command\n" \ + "\t-r\tDo not run command for empty readed lines\n" \ + "\t-t\tPrint the command line on stderr before executing it." #define xargs_example_usage \ "$ ls | xargs gzip\n" \ "$ find . -name '*.c' -print | xargs rm\n"