mp-utils/src/wc.c

/* wc.c -- program to count and display the number of lines, words and one of bytes or characters in the named files */


#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <ctype.h>

#include "support.h"


/* Parameters */
enum
    {
    W,
    L,
    CM
    };

/* States */
enum {
    OUTWORD,
    INWORD
    };

/* Category names for count[] and result[] */
enum {
    /* character or byte */
    LINES,
    WORDS,
    COB
    };


int wc(FILE *fd, int *results)
    {
    char state;
    int c;

    state = OUTWORD;
    c = 0;
    

    for(c = 0; (c = fgetc(fd)) != EOF;)
	{
	if(!(isblank(c) || c == '\n'))
	    {
	    if(state == OUTWORD)
		{
		results[WORDS]++;
		}

	    state = INWORD;
	    }
	else
	    {
	    if(c == '\n')
		{
		results[LINES]++;
		}

	    state = OUTWORD;
	    }

	results[COB]++;
	}

    
    return(0);
    }

/* if a particular pars element is non-zero, print the corresponding total element. */
/* if pars is NULL, print everything */
/* if total is NULL, throw an error */
int printres(int *total, char *filepath, char *pars)
    {
    int i;

    i = 0;


    if(!total)
	{
	throw(MISC_FAIL, "printres: total is null");
	}

    
    for(i = 0; i <= 2; i++)
	{
	if(pars == NULL || pars[i])
	    {
	    printf("%d ", total[i]);
	    }
	}

    if(filepath)
	{
	if(!strcmp("-", filepath))
	    {
	    printf("stdin");
	    }
	else
	    {
	    printf("%s", filepath);
	    }
	}
    putchar('\n');
    
    
    return(0);
    }

int main(int argc, char **argv)
    {
    /* haspar == 0 means we pass NULL to printres for default POSIX behavior */
    char haspar;
    int c, i;
    int current[3] = {0};
    int results[3] = {0};

    char pars[3] = {0};
    FILE *fd;

    haspar = 0;
    /* c value is arbitrary but is non-NULL for safety reasons; i is used to ensure the program does not open itself */
    c = i = 1;

    fd = 0;

    
    /* process our parameters */
    for(; (c = getopt(argc, argv, "cmlw")) != -1; c = 0)
	{
	switch(c)
	    {
	    case 'c': pars[CM] = 1;
		haspar = 1;
		break;
	    case 'm': pars[CM] = -1;
		haspar = 1;
		break;
	    case 'l': pars[L] = 1;
		haspar = 1;
		break;
	    case 'w': pars[W] = 1;
		haspar = 1;
		break;
		/* Fall-through to default from ':' */
	    case ':': 
	    case '?':
	    default: throw(NEEDARG_FAIL, mastrcat(argv[0], " [-c|-m] [-lw] [file ...]"));
		break;
	    }
	}
    i = optind;

    /* do-while allows easy opening of stdin */
    do
	{
	/* open file */
	fd = file_open(argv[i], "r");
	
	/* process file */
	wc(fd, current);
	
	/* print results */
	if(haspar)
	    {
	    printres(current, argv[i], pars);
	    }
	else
	    {
	    printres(current, argv[i], NULL);
	    }
	
	/* add results to global count */
	results[WORDS] += current[WORDS];
	results[LINES] += current[LINES];
	results[COB] += current[COB];
	
/* reset count and file descriptor */
	current[WORDS] = 0;
	current[LINES] = 0;
	current[COB] = 0;

	fclose(fd);
	}
    /* this would normally be a pre-increment, but that can be confusing, so we use a more explicit approach here */
    while((i+=1) <  argc);

    
    exit(0);
    }