| /* vi: set sw=4 ts=4: */ |
| /* |
| * cut.c - minimalist version of cut |
| * |
| * Copyright (C) 1999,2000,2001 by Lineo, inc. |
| * Written by Mark Whitley <markw@codepoet.org> |
| * debloated by Bernhard Reutner-Fischer |
| * |
| * Licensed under GPLv2 or later, see file LICENSE in this source tree. |
| */ |
| //config:config CUT |
| //config: bool "cut (5.8 kb)" |
| //config: default y |
| //config: help |
| //config: cut is used to print selected parts of lines from |
| //config: each file to stdout. |
| |
| //applet:IF_CUT(APPLET_NOEXEC(cut, cut, BB_DIR_USR_BIN, BB_SUID_DROP, cut)) |
| |
| //kbuild:lib-$(CONFIG_CUT) += cut.o |
| |
| //usage:#define cut_trivial_usage |
| //usage: "[OPTIONS] [FILE]..." |
| //usage:#define cut_full_usage "\n\n" |
| //usage: "Print selected fields from FILEs to stdout\n" |
| //usage: "\n -b LIST Output only bytes from LIST" |
| //usage: "\n -c LIST Output only characters from LIST" |
| //usage: "\n -d CHAR Use CHAR instead of tab as field delimiter" |
| //usage: "\n -s Output only lines containing delimiter" |
| //usage: "\n -f LIST Print only these fields" |
| //usage: "\n -n Ignored" |
| //(manpage:-n with -b: don't split multibyte characters) |
| //usage: |
| //usage:#define cut_example_usage |
| //usage: "$ echo \"Hello world\" | cut -f 1 -d ' '\n" |
| //usage: "Hello\n" |
| //usage: "$ echo \"Hello world\" | cut -f 2 -d ' '\n" |
| //usage: "world\n" |
| |
| #include "libbb.h" |
| |
| /* This is a NOEXEC applet. Be very careful! */ |
| |
| |
| /* option vars */ |
| #define OPT_STR "b:c:f:d:sn" |
| #define CUT_OPT_BYTE_FLGS (1 << 0) |
| #define CUT_OPT_CHAR_FLGS (1 << 1) |
| #define CUT_OPT_FIELDS_FLGS (1 << 2) |
| #define CUT_OPT_DELIM_FLGS (1 << 3) |
| #define CUT_OPT_SUPPRESS_FLGS (1 << 4) |
| |
| struct cut_list { |
| int startpos; |
| int endpos; |
| }; |
| |
| enum { |
| BOL = 0, |
| EOL = INT_MAX, |
| NON_RANGE = -1 |
| }; |
| |
| static int cmpfunc(const void *a, const void *b) |
| { |
| return (((struct cut_list *) a)->startpos - |
| ((struct cut_list *) b)->startpos); |
| } |
| |
| static void cut_file(FILE *file, char delim, const struct cut_list *cut_lists, unsigned nlists) |
| { |
| char *line; |
| unsigned linenum = 0; /* keep these zero-based to be consistent */ |
| |
| /* go through every line in the file */ |
| while ((line = xmalloc_fgetline(file)) != NULL) { |
| |
| /* set up a list so we can keep track of what's been printed */ |
| int linelen = strlen(line); |
| char *printed = xzalloc(linelen + 1); |
| char *orig_line = line; |
| unsigned cl_pos = 0; |
| int spos; |
| |
| /* cut based on chars/bytes XXX: only works when sizeof(char) == byte */ |
| if (option_mask32 & (CUT_OPT_CHAR_FLGS | CUT_OPT_BYTE_FLGS)) { |
| /* print the chars specified in each cut list */ |
| for (; cl_pos < nlists; cl_pos++) { |
| spos = cut_lists[cl_pos].startpos; |
| while (spos < linelen) { |
| if (!printed[spos]) { |
| printed[spos] = 'X'; |
| putchar(line[spos]); |
| } |
| spos++; |
| if (spos > cut_lists[cl_pos].endpos |
| /* NON_RANGE is -1, so if below is true, |
| * the above was true too (spos is >= 0) */ |
| /* || cut_lists[cl_pos].endpos == NON_RANGE */ |
| ) { |
| break; |
| } |
| } |
| } |
| } else if (delim == '\n') { /* cut by lines */ |
| spos = cut_lists[cl_pos].startpos; |
| |
| /* get out if we have no more lists to process or if the lines |
| * are lower than what we're interested in */ |
| if (((int)linenum < spos) || (cl_pos >= nlists)) |
| goto next_line; |
| |
| /* if the line we're looking for is lower than the one we were |
| * passed, it means we displayed it already, so move on */ |
| while (spos < (int)linenum) { |
| spos++; |
| /* go to the next list if we're at the end of this one */ |
| if (spos > cut_lists[cl_pos].endpos |
| || cut_lists[cl_pos].endpos == NON_RANGE |
| ) { |
| cl_pos++; |
| /* get out if there's no more lists to process */ |
| if (cl_pos >= nlists) |
| goto next_line; |
| spos = cut_lists[cl_pos].startpos; |
| /* get out if the current line is lower than the one |
| * we just became interested in */ |
| if ((int)linenum < spos) |
| goto next_line; |
| } |
| } |
| |
| /* If we made it here, it means we've found the line we're |
| * looking for, so print it */ |
| puts(line); |
| goto next_line; |
| } else { /* cut by fields */ |
| int ndelim = -1; /* zero-based / one-based problem */ |
| int nfields_printed = 0; |
| char *field = NULL; |
| char delimiter[2]; |
| |
| delimiter[0] = delim; |
| delimiter[1] = 0; |
| |
| /* does this line contain any delimiters? */ |
| if (strchr(line, delim) == NULL) { |
| if (!(option_mask32 & CUT_OPT_SUPPRESS_FLGS)) |
| puts(line); |
| goto next_line; |
| } |
| |
| /* process each list on this line, for as long as we've got |
| * a line to process */ |
| for (; cl_pos < nlists && line; cl_pos++) { |
| spos = cut_lists[cl_pos].startpos; |
| do { |
| /* find the field we're looking for */ |
| while (line && ndelim < spos) { |
| field = strsep(&line, delimiter); |
| ndelim++; |
| } |
| |
| /* we found it, and it hasn't been printed yet */ |
| if (field && ndelim == spos && !printed[ndelim]) { |
| /* if this isn't our first time through, we need to |
| * print the delimiter after the last field that was |
| * printed */ |
| if (nfields_printed > 0) |
| putchar(delim); |
| fputs_stdout(field); |
| printed[ndelim] = 'X'; |
| nfields_printed++; /* shouldn't overflow.. */ |
| } |
| |
| spos++; |
| |
| /* keep going as long as we have a line to work with, |
| * this is a list, and we're not at the end of that |
| * list */ |
| } while (spos <= cut_lists[cl_pos].endpos && line |
| && cut_lists[cl_pos].endpos != NON_RANGE); |
| } |
| } |
| /* if we printed anything at all, we need to finish it with a |
| * newline cuz we were handed a chomped line */ |
| putchar('\n'); |
| next_line: |
| linenum++; |
| free(printed); |
| free(orig_line); |
| } |
| } |
| |
| int cut_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
| int cut_main(int argc UNUSED_PARAM, char **argv) |
| { |
| /* growable array holding a series of lists */ |
| struct cut_list *cut_lists = NULL; |
| unsigned nlists = 0; /* number of elements in above list */ |
| char delim = '\t'; /* delimiter, default is tab */ |
| char *sopt, *ltok; |
| unsigned opt; |
| |
| opt = getopt32(argv, "^" |
| OPT_STR |
| "\0" "b--bcf:c--bcf:f--bcf", |
| &sopt, &sopt, &sopt, <ok |
| ); |
| // argc -= optind; |
| argv += optind; |
| if (!(opt & (CUT_OPT_BYTE_FLGS | CUT_OPT_CHAR_FLGS | CUT_OPT_FIELDS_FLGS))) |
| bb_simple_error_msg_and_die("expected a list of bytes, characters, or fields"); |
| |
| if (opt & CUT_OPT_DELIM_FLGS) { |
| if (ltok[0] && ltok[1]) { /* more than 1 char? */ |
| bb_simple_error_msg_and_die("the delimiter must be a single character"); |
| } |
| delim = ltok[0]; |
| } |
| |
| /* non-field (char or byte) cutting has some special handling */ |
| if (!(opt & CUT_OPT_FIELDS_FLGS)) { |
| static const char _op_on_field[] ALIGN1 = " only when operating on fields"; |
| |
| if (opt & CUT_OPT_SUPPRESS_FLGS) { |
| bb_error_msg_and_die |
| ("suppressing non-delimited lines makes sense%s", |
| _op_on_field); |
| } |
| if (delim != '\t') { |
| bb_error_msg_and_die |
| ("a delimiter may be specified%s", _op_on_field); |
| } |
| } |
| |
| /* |
| * parse list and put values into startpos and endpos. |
| * valid list formats: N, N-, N-M, -M |
| * more than one list can be separated by commas |
| */ |
| { |
| char *ntok; |
| int s = 0, e = 0; |
| |
| /* take apart the lists, one by one (they are separated with commas) */ |
| while ((ltok = strsep(&sopt, ",")) != NULL) { |
| |
| /* it's actually legal to pass an empty list */ |
| if (!ltok[0]) |
| continue; |
| |
| /* get the start pos */ |
| ntok = strsep(<ok, "-"); |
| if (!ntok[0]) { |
| s = BOL; |
| } else { |
| s = xatoi_positive(ntok); |
| /* account for the fact that arrays are zero based, while |
| * the user expects the first char on the line to be char #1 */ |
| if (s != 0) |
| s--; |
| } |
| |
| /* get the end pos */ |
| if (ltok == NULL) { |
| e = NON_RANGE; |
| } else if (!ltok[0]) { |
| e = EOL; |
| } else { |
| e = xatoi_positive(ltok); |
| /* if the user specified and end position of 0, |
| * that means "til the end of the line" */ |
| if (e == 0) |
| e = EOL; |
| e--; /* again, arrays are zero based, lines are 1 based */ |
| if (e == s) |
| e = NON_RANGE; |
| } |
| |
| /* add the new list */ |
| cut_lists = xrealloc_vector(cut_lists, 4, nlists); |
| /* NB: startpos is always >= 0, |
| * while endpos may be = NON_RANGE (-1) */ |
| cut_lists[nlists].startpos = s; |
| cut_lists[nlists].endpos = e; |
| nlists++; |
| } |
| |
| /* make sure we got some cut positions out of all that */ |
| if (nlists == 0) |
| bb_simple_error_msg_and_die("missing list of positions"); |
| |
| /* now that the lists are parsed, we need to sort them to make life |
| * easier on us when it comes time to print the chars / fields / lines |
| */ |
| qsort(cut_lists, nlists, sizeof(cut_lists[0]), cmpfunc); |
| } |
| |
| { |
| int retval = EXIT_SUCCESS; |
| |
| if (!*argv) |
| *--argv = (char *)"-"; |
| |
| do { |
| FILE *file = fopen_or_warn_stdin(*argv); |
| if (!file) { |
| retval = EXIT_FAILURE; |
| continue; |
| } |
| cut_file(file, delim, cut_lists, nlists); |
| fclose_if_not_stdin(file); |
| } while (*++argv); |
| |
| if (ENABLE_FEATURE_CLEAN_UP) |
| free(cut_lists); |
| fflush_stdout_and_exit(retval); |
| } |
| } |