/* cut - extract columns from a file or stdin. Author: Michael J. Holme * * Copyright 1989, Michael John Holme, All rights reserved. * This code may be freely distributed, provided that this notice * remains intact. * * V1.1: 6th September 1989 * * Bugs, criticisms, etc, * c/o Mark Powell * JANET sq79@uk.ac.liv * ARPA sq79%liv.ac.uk@nsfnet-relay.ac.uk * UUCP ...!mcvax!ukc!liv.ac.uk!sq79 *------------------------------------------------------------------------- * Changed for POSIX1003.2/Draft10 conformance * Thomas Brupbacher (tobr@mw.lpc.ethz.ch), September 1990. * Changes: * - separation of error messages ( stderr) and output (stdout). * - support for -b and -n (no effect, -b acts as -c) * - support for -s *------------------------------------------------------------------------- */ #include #include #include #include #include #include #define MAX_FIELD 80 /* Pointers to the beginning of each field * are stored in columns[], if a line holds * more than MAX_FIELD columns the array * boundary is exceed. But unlikely at 80 */ #define MAX_ARGS 32 /* Maximum number of fields following -f or * -c switches */ int args[MAX_ARGS * 2]; int num_args; /* Lots of new defines, should easen maintainance... */ #define DUMP_STDIN 0 /* define for mode: no options */ #define OPTIONF 1 /* define for mode: option -f */ #define OPTIONC 2 /* define for mode: option -c */ #define OPTIONB 3 /* define for mode: option -b */ #define NOTSET 0 /* option not selected */ #define SET 1 /* option selected */ /* Defines for the warnings */ #define DELIMITER_NOT_APPLICABLE 0 #define OVERRIDING_PREVIOUS_MODE 1 #define OPTION_NOT_APPLICABLE 2 #define UNKNOWN_OPTION 3 #define FILE_NOT_READABLE 4 /* Defines for the fatal errors */ #define SYNTAX_ERROR 101 #define POSITION_ERROR 102 #define USAGE 103 #define LINE_TO_LONG_ERROR 104 #define RANGE_ERROR 105 #define MAX_FIELDS_EXEEDED_ERROR 106 #define MAX_ARGS_EXEEDED_ERROR 107 int mode; /* 0 = dump stdin to stdout, 1=-f, 2=-c */ int flag_i; /* SET = -i set on command line */ int flag_s; /* SET = -s set on command line */ char delim = '\t'; /* default delimiting character */ FILE *fd; char *name; char line[BUFSIZ]; int exit_status; _PROTOTYPE(int main, (int argc, char **argv)); _PROTOTYPE(void warn, (int warn_number, char *option)); _PROTOTYPE(void cuterror, (int err)); _PROTOTYPE(void get_args, (void)); _PROTOTYPE(void cut, (void)); void warn(warn_number, option) int warn_number; char *option; { static char *warn_msg[] = { "%s: Option -d allowed only with -f\n", "%s: -%s overrides earlier option\n", "%s: -%s not allowed in current mode\n", "%s: Cannot open %s\n" }; fprintf(stderr, warn_msg[warn_number], name, option); exit_status = warn_number + 1; } void cuterror(err) int err; { static char *err_mes[] = { "%s: syntax error\n", "%s: position must be >0\n", "%s: usage: cut [-f args [-i] [-d x]]|[-c args] [filename [...]]\n", "%s: line longer than BUFSIZ\n", "%s: range must not decrease from left to right\n", "%s: MAX_FIELD exceeded\n", "%s: MAX_ARGS exceeded\n" }; fprintf(stderr, err_mes[err - 101], name); exit(err); } void get_args() { int i = 0; int arg_ptr = 0; int flag; num_args = 0; do { if (num_args == MAX_ARGS) cuterror(MAX_ARGS_EXEEDED_ERROR); if (!isdigit(line[i]) && line[i] != '-') cuterror(SYNTAX_ERROR); args[arg_ptr] = 1; args[arg_ptr + 1] = BUFSIZ; flag = 1; while (line[i] != ',' && line[i] != 0) { if (isdigit(line[i])) { args[arg_ptr] = 0; while (isdigit(line[i])) args[arg_ptr] = 10 * args[arg_ptr] + line[i++] - '0'; if (!args[arg_ptr]) cuterror(POSITION_ERROR); arg_ptr++; } if (line[i] == '-') { arg_ptr |= 1; i++; flag = 0; } } if (flag && arg_ptr & 1) args[arg_ptr] = args[arg_ptr - 1]; if (args[num_args * 2] > args[num_args * 2 + 1]) cuterror(RANGE_ERROR); num_args++; arg_ptr = num_args * 2; } while (line[i++]); } void cut() { int i, j, length, maxcol; char *columns[MAX_FIELD]; while (fgets(line, BUFSIZ, fd)) { length = strlen(line) - 1; *(line + length) = 0; switch (mode) { case DUMP_STDIN: printf("%s", line); break; case OPTIONF: maxcol = 0; columns[maxcol++] = line; for (i = 0; i < length; i++) { if (*(line + i) == delim) { *(line + i) = 0; if (maxcol == MAX_FIELD) cuterror(MAX_FIELDS_EXEEDED_ERROR); columns[maxcol] = line + i + 1; while (*(line + i + 1) == delim && flag_i) { columns[maxcol]++; i++; } maxcol++; } } if (maxcol == 1) { if (flag_s != SET) printf("%s", line); } else { for (i = 0; i < num_args; i++) { for (j = args[i * 2]; j <= args[i * 2 + 1]; j++) if (j <= maxcol) { printf("%s", columns[j - 1]); if (i != num_args - 1 || j != args[i * 2 + 1]) putchar(delim); } } } break; case OPTIONC: for (i = 0; i < num_args; i++) { for (j = args[i * 2]; j <= (args[i * 2 + 1] > length ? length : args[i * 2 + 1]); j++) putchar(*(line + j - 1)); } } if (maxcol == 1 && flag_s == SET); else putchar('\n'); } } int main(argc, argv) int argc; char *argv[]; { int i = 1; int numberFilenames = 0; name = argv[0]; if (argc == 1) cuterror(USAGE); while (i < argc) { if (argv[i][0] == '-') { switch (argv[i++][1]) { case 'd': if (mode == OPTIONC || mode == OPTIONB) warn(DELIMITER_NOT_APPLICABLE, "d"); delim = argv[i++][0]; break; case 'f': sprintf(line, "%s", argv[i++]); if (mode == OPTIONC || mode == OPTIONB) warn(OVERRIDING_PREVIOUS_MODE, "f"); mode = OPTIONF; break; case 'b': sprintf(line, "%s", argv[i++]); if (mode == OPTIONF || mode == OPTIONC) warn(OVERRIDING_PREVIOUS_MODE, "b"); mode = OPTIONB; break; case 'c': sprintf(line, "%s", argv[i++]); if (mode == OPTIONF || mode == OPTIONB) warn(OVERRIDING_PREVIOUS_MODE, "c"); mode = OPTIONC; break; case 'i': flag_i = SET; break; case 's': flag_s = SET; break; case '\0': /* - means: read from stdin */ numberFilenames++; break; case 'n': /* needed for Posix, but no effect here */ if (mode != OPTIONB) warn(OPTION_NOT_APPLICABLE, "n"); break; default: warn(UNKNOWN_OPTION, &(argv[i - 1][1])); } } else { i++; numberFilenames++; } } /* Here follow the checks, if the selected options are reasonable. */ if (mode == OPTIONB) /* since in Minix char := byte */ mode = OPTIONC; /* Flag -s is only allowed with -f, otherwise warn and reset flag_s */ if (flag_s == SET && (mode == OPTIONB || mode == OPTIONC)) { warn(OPTION_NOT_APPLICABLE, "s"); flag_s = NOTSET; } /* Flag -i is only allowed with -f, otherwise warn and reset flag_i */ if (flag_i == SET && mode == OPTIONF) { warn(OPTION_NOT_APPLICABLE, "s"); flag_i = NOTSET; } get_args(); if (numberFilenames != 0) { i = 1; while (i < argc) { if (argv[i][0] == '-') { switch (argv[i][1]) { case 'f': case 'c': case 'b': case 'd': i += 2; break; case 'n': case 'i': case 's': i++; break; case '\0': fd = stdin; i++; cut(); break; default: i++; } } else { if ((fd = fopen(argv[i++], "r")) == NULL) { warn(FILE_NOT_READABLE, argv[i - 1]); } else { cut(); fclose(fd); } } } } else { fd = stdin; cut(); } return(exit_status); }