BSD 4_1c_2 release

[unix-history] / usr / src / ucb / from.c

static char *sccsid = "@(#)from.c       4.1 (Berkeley) 10/1/80";
#include <stdio.h>
#include <ctype.h>
#include <pwd.h>

struct  passwd *getpwuid();

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;
       char *getlogin();

       if (argc > 1 && *(argv[1]) == '-' && (*++argv)[1] == 's') {
               if (--argc <= 1) {
                       fprintf (stderr, "Usage: from [-s sender] [user]\n");
                       exit (1);
               }
               --argc;
               sender = *++argv;
               for (name = sender; *name; name++)
                       if (isupper(*name))
                               *name = tolower(*name);

       }
       else
               sender = NULL;
       if (chdir("/usr/spool/mail") < 0)
               exit(1);
       if (argc > 1)
               name = argv[1];
       else {
               name = getlogin ();
               if (name == NULL || strlen(name) == 0) {
                       pp = getpwuid(getuid());
                       if (pp == NULL) {
                               fprintf(stderr, "Who are you?\n");
                               exit(1);
                       }
                       name = pp->pw_name;
               }
       }
       if (freopen(name, "r", stdin) == NULL)
               exit(0);
       while(fgets(lbuf, sizeof lbuf, stdin) != NULL)
               if (lbuf[0] == '\n' && stashed) {
                       stashed = 0;
                       printf("%s", lbuf2);
               }
               else if (bufcmp(lbuf, "From ", 5) &&
                   (sender == NULL || match(&lbuf[4], sender))) {
                       strcpy(lbuf2, lbuf);
                       stashed = 1;
               }
       if (stashed)
               printf("%s", lbuf2);
       exit(0);
}

bufcmp (b1, b2, n)
register char *b1, *b2;
register int n;
{
       while (n-- > 0)
               if (*b1++ != *b2++)
                       return (0);
       return (1);
}

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');
}