/* * Mini xargs implementation for busybox * Only "-prt" options are supported in this version of xargs. * * (C) 2002 by Vladimir Oleynik * (C) 2003 by Glenn McGrath * * 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 * 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 * */ #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]; bb_perror_msg_and_die("%s", args[0]); } } } else { bb_perror_msg_and_die("vfork"); } } #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 int xargs_main(int argc, char **argv) { char *s_max_args = NULL; char *s_line_size = NULL; unsigned long flg; char *eof_string = "_"; int line_size = LINE_MAX; unsigned int max_args = LINE_MAX / 2; char *line_buffer = NULL; char *line_buffer_ptr_ptr; char *old_arg = NULL; char **args; char *args_entry_ptr; int i; int a; bb_opt_complementaly = "pt"; flg = bb_getopt_ulflags(argc, argv, "+tpxn:s:E::", &s_max_args, &s_line_size, &eof_string); if (s_max_args) { max_args = bb_xgetularg10(s_max_args); } if (s_line_size) { line_size = bb_xgetularg10(s_line_size); } a = argc - optind; argv += optind; if(a==0) { /* default behavior is to echo all the filenames */ *argv = "echo"; a++; } /* 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++; } if (line_size < 1) { bb_error_msg_and_die("can not 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; } if (eof_string && (strcmp(line_buffer_ptr, eof_string) == 0)) { /* logical EOF, exit outer loop */ line_buffer = NULL; break; } /* 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; } /* 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); } fputs(((flg & OPT_INTERACTIVE) ? " ?..." : "\n"), stderr); } if((flg & OPT_INTERACTIVE) == 0 || bb_ask_confirmation() != 0 ) { xargs_exec(args); } } } while (line_buffer); #ifdef CONFIG_FEATURE_CLEAN_UP free(args); #endif return 0; }