diff options
Diffstat (limited to 'coreutils/cut.c')
-rw-r--r-- | coreutils/cut.c | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/coreutils/cut.c b/coreutils/cut.c new file mode 100644 index 000000000..a538e3d20 --- /dev/null +++ b/coreutils/cut.c @@ -0,0 +1,285 @@ +/* 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; +} |