ucbcmd/from/from.c

	from.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * Copyright 1994 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * Copyright (c) 1980 Regents of the University of California.
 * All rights reserved.  The Berkeley software License Agreement
 * specifies the terms and conditions for redistribution.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include <stdio.h>
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
#include <ctype.h>
#include <pwd.h>
#include <sys/param.h>
#include <string.h>

static int match(char *, char *);

main(argc, argv)
    int argc;
    register char **argv;
{
    char lbuf[BUFSIZ];
    char lbuf2[BUFSIZ];
    register struct passwd *pp;
    int stashed = 0;
    register char *name;
    char *sender = NULL;
    char mailbox[MAXPATHLEN];
    char *tmp_mailbox;
    extern char *optarg;
    extern int optind;
    extern int opterr;
    int c;
    int errflg = 0;

    opterr = 0;
    while ((c = getopt(argc, argv, "s:")) != EOF)
        switch (c) {
        case 's':
            sender = optarg;
            for (name = sender; *name; name++)
                if (isupper(*name))
                    *name = tolower(*name);
            break;
        case '?':
            errflg++;
            break;
        }
    if (errflg) {
        (void) fprintf(stderr,
                "Usage: from [-s sender] [user]\n");
        exit(1);
    }

    if (optind < argc) {
        (void) sprintf(mailbox, "/var/mail/%s", argv[optind]);
    } else {
        if (tmp_mailbox = getenv("MAIL")) {
            (void) strcpy(mailbox, tmp_mailbox);
        } else {
            name = getlogin();
            if (name == NULL || strlen(name) == 0) {
                pp = getpwuid(getuid());
                if (pp == NULL) {
                    (void) fprintf(stderr,
                        "Who are you?\n");
                    exit(1);
                }
                name = pp->pw_name;
            }
            (void) sprintf(mailbox, "/var/mail/%s", name);
        }
    }
    if (freopen(mailbox, "r", stdin) == NULL) {
        (void) fprintf(stderr, "Can't open %s\n", mailbox);
        exit(0);
    }
    while (fgets(lbuf, sizeof (lbuf), stdin) != NULL)
        if (lbuf[0] == '\n' && stashed) {
            stashed = 0;
            (void) printf("%s", lbuf2);
        } else if (strncmp(lbuf, "From ", 5) == 0 &&
            (sender == NULL || match(&lbuf[4], sender))) {
            (void) strcpy(lbuf2, lbuf);
            stashed = 1;
        }
    if (stashed)
        (void) printf("%s", lbuf2);
    return(0);
}

static int
match(line, str)
    register char *line, *str;
{
    register char ch;

    while (*line == ' ' || *line == '\t')
        ++line;
    if (*line == '\n')
        return (0);
    while (*str && *line != ' ' && *line != '\t' && *line != '\n') {
        ch = isupper(*line) ? tolower(*line) : *line;
        if (ch != *str++)
            return (0);
        line++;
    }
    return (*str == '\0');
}