minix/commands/simple/cut.c

322 lines
7.8 KiB
C

/* 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 <sys/types.h>
#include <ctype.h>
#include <string.h>
#include <errno.h>
#include <stdlib.h>
#include <stdio.h>
#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++;
} else if (line[i] != '-') {
cuterror(SYNTAX_ERROR);
}
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[];
{
char *linearg;
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 - 1][2] ?
argv[i - 1][2] : argv[i++][0];
break;
case 'f':
linearg = argv[i - 1][2] ?
(argv[i - 1] + 2) : argv[i++];
sprintf(line, "%s", linearg);
if (mode == OPTIONC || mode == OPTIONB)
warn(OVERRIDING_PREVIOUS_MODE, "f");
mode = OPTIONF;
break;
case 'b':
linearg = argv[i - 1][2] ?
(argv[i - 1] + 2) : argv[i++];
sprintf(line, "%s", linearg);
if (mode == OPTIONF || mode == OPTIONC)
warn(OVERRIDING_PREVIOUS_MODE, "b");
mode = OPTIONB;
break;
case 'c':
linearg = argv[i - 1][2] ?
(argv[i - 1] + 2) : argv[i++];
sprintf(line, "%s", linearg);
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 += argv[i][2] ? 1 : 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);
}