| /* 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 Fischer |
| * |
| * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. |
| */ |
| |
| #include "busybox.h" |
| |
| /* option vars */ |
| static const char optstring[] = "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) |
| |
| static char delim = '\t'; /* delimiter, default is tab */ |
| |
| struct cut_list { |
| int startpos; |
| int endpos; |
| }; |
| |
| enum { |
| BOL = 0, |
| EOL = INT_MAX, |
| NON_RANGE = -1 |
| }; |
| |
| /* growable array holding a series of lists */ |
| static struct cut_list *cut_lists; |
| static unsigned int nlists; /* number of elements in above list */ |
| |
| |
| 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 *line = NULL; |
| unsigned int linenum = 0; /* keep these zero-based to be consistent */ |
| |
| /* go through every line in the file */ |
| while ((line = xmalloc_getline(file)) != NULL) { |
| |
| /* set up a list so we can keep track of what's been printed */ |
| char * printed = xzalloc(strlen(line) * sizeof(char)); |
| char * orig_line = line; |
| unsigned int 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 < strlen(line)) { |
| if (!printed[spos]) { |
| printed[spos] = 'X'; |
| putchar(line[spos]); |
| } |
| spos++; |
| if (spos > cut_lists[cl_pos].endpos |
| || 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 (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 < 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 (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; |
| const char delimiter[2] = { delim, 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(field, stdout); |
| 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); |
| } |
| } |
| |
| static const char _op_on_field[] = " only when operating on fields"; |
| |
| int cut_main(int argc, char **argv) |
| { |
| char *sopt, *ltok; |
| |
| opt_complementary = "b--bcf:c--bcf:f--bcf"; |
| getopt32(argc, argv, optstring, &sopt, &sopt, &sopt, <ok); |
| if (!(option_mask32 & (CUT_OPT_BYTE_FLGS | CUT_OPT_CHAR_FLGS | CUT_OPT_FIELDS_FLGS))) |
| bb_error_msg_and_die("expected a list of bytes, characters, or fields"); |
| if (option_mask32 & BB_GETOPT_ERROR) |
| bb_error_msg_and_die("only one type of list may be specified"); |
| |
| if (option_mask32 & CUT_OPT_DELIM_FLGS) { |
| if (strlen(ltok) > 1) { |
| bb_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 (!(option_mask32 & CUT_OPT_FIELDS_FLGS)) { |
| if (option_mask32 & 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 (strlen(ltok) == 0) |
| continue; |
| |
| /* get the start pos */ |
| ntok = strsep(<ok, "-"); |
| if (ntok == NULL) { |
| bb_error_msg |
| ("internal error: ntok is null for start pos!?\n"); |
| } else if (strlen(ntok) == 0) { |
| s = BOL; |
| } else { |
| s = xatoi_u(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 */ |
| ntok = strsep(<ok, "-"); |
| if (ntok == NULL) { |
| e = NON_RANGE; |
| } else if (strlen(ntok) == 0) { |
| e = EOL; |
| } else { |
| e = xatoi_u(ntok); |
| /* 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; |
| } |
| |
| /* if there's something left to tokenize, the user passed |
| * an invalid list */ |
| if (ltok) |
| bb_error_msg_and_die("invalid byte or field list"); |
| |
| /* add the new list */ |
| cut_lists = xrealloc(cut_lists, sizeof(struct cut_list) * (++nlists)); |
| cut_lists[nlists-1].startpos = s; |
| cut_lists[nlists-1].endpos = e; |
| } |
| |
| /* make sure we got some cut positions out of all that */ |
| if (nlists == 0) |
| bb_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(struct cut_list), cmpfunc); |
| } |
| |
| /* argv[(optind)..(argc-1)] should be names of file to process. If no |
| * files were specified or '-' was specified, take input from stdin. |
| * Otherwise, we process all the files specified. */ |
| if (argv[optind] == NULL |
| || (argv[optind][0] == '-' && argv[optind][1] == '\0')) { |
| cut_file(stdin); |
| } else { |
| FILE *file; |
| |
| for (; optind < argc; optind++) { |
| file = fopen_or_warn(argv[optind], "r"); |
| if (file) { |
| cut_file(file); |
| fclose(file); |
| } |
| } |
| } |
| if (ENABLE_FEATURE_CLEAN_UP) |
| free(cut_lists); |
| return EXIT_SUCCESS; |
| } |