Usenet 1994 January/usenetsourcesnewsgroupsinfomagicjanuary1994.iso/sources/unix/volume14/mush6.0/part02/aliases.c

C/C++ Source or Header | 1988-04-12 | 4.5 KB | 177 lines

/* (c) copyright @(#)aliases.c    2.4    10/15/86 (Dan Heller) */

#include "mush.h"

/*
 * do_alias handles aliases, header settings, functions, and fkeys.
 * since they're all handled in the same manner, the same routine is
 * used. argv[0] determines which to use.
 * alias is given here as an example
 *
 * alias           identify all aliases
 * alias name      identify alias
 * alias name arg1 arg2 arg3... -> name="arg1 arg2 arg3"; call set_option
 * unalias arg1 [arg2 arg3 ... ]        unalias args
 *
 * same is true for dealing with your own headers.
 * (also the expand command)
 * always return -1 since it nas no effect on messages
 */
do_alias(argc, argv)
register char **argv;
{
    register char *cmd = *argv, *p;
    struct options **list;
    char firstchar = *cmd, buf[BUFSIZ];

    if (argc == 0)
    return -1;
    if (firstchar == 'u')
    firstchar = cmd[2];
    if (*++argv && !strcmp(*argv, "-?")) { /* doesn't apply for fkeys */
    register char *help_str;
    if (firstchar == 'a' || firstchar == 'e')
        help_str = "alias";
    else if (firstchar == 'c')
        help_str = "func_help";
    else if (firstchar == 'f')
        help_str = "fkey_help";
    else
        help_str = "own_hdrs";
    return help(0, help_str, cmd_help);
    }

    if (firstchar == 'a')
    list = &aliases;
    else if (firstchar == 'c')
    list = &functions;
    else if (firstchar == 'f')
    list = &fkeys;
    else
    list = &own_hdrs;

    if (*cmd == 'u') {
    if (!*argv)
        print("%s what?\n", cmd);
    /* unset a list separated by spaces or ',' */
    else while (*argv) {
        if (!strcmp(*argv, "*")) /* unset everything */
        while (*list)
            (void) un_set(list, (*list)->option);
        else if (!un_set(list, *argv))
        print("\"%s\" isn't set\n", *argv);
        argv++;
    }
    return -1;
    }

    if (!*argv && *cmd != 'e') {
    /* just type out all the aliases or own_hdrs */
    (void) do_set(*list, NULL);
    return -1;
    }

    if (*cmd == 'e') {   /* command was "expand" (aliases only) */
    if (!*argv)
        print("expand which alias?\n");
    else
        do  {
        print("%s: ", *argv);
        if (p = alias_to_address(*argv))
            print("%s\n", p);
        } while (*++argv);
    return -1;
    }

    /* at this point, *argv now points to a variable name ...
     * check for hdr -- if so, *argv better end with a ':' (check *p)
     */
    if (list == &own_hdrs && !(p = index(*argv, ':'))) {
    print("header labels must end with a ':' (%s)\n", *argv);
    return -1;
    }
    if (!argv[1] && !index(*argv, '='))
    if (p = do_set(*list, *argv))
        print("%s\n", p);
    else
        print("%s is not set\n", *argv);
    else {
    char *tmpargv[2];
    (void) argv_to_string(buf, argv);
    if ((p = any(buf, " \t=")) && *p != '=')
        *p = '=';
    /* if we're setting an alias, enforce the insertion of commas
     * between each well-formed address.
     */
    if (list == &aliases)
        fix_up_addr(p+1);
    tmpargv[0] = buf;
    tmpargv[1] = NULL;
    (void) add_option(list, tmpargv);
    }
    return -1;
}

/* takes string 's' which can be a name or list of names separated by
 * commas and checks to see if each is aliased to something else.
 * return address of the static buf.
 */
char *
alias_to_address(s)
register char *s;
{
    static char buf[BUFSIZ];
    register char *p, *p2, *tmp;
    char newbuf[BUFSIZ], c;
    static int recursive;

    if (!aliases)
    return strcpy(buf, s);
    if (!s || !*s) {
    print("No recipeints!?!\n");
    return NULL;
    }
    if (!recursive) {
    bzero(buf, BUFSIZ);
    p2 = buf;  /* if we're starting all this, p2 starts at &buf[0] */
    } else
    p2 = buf+strlen(buf);   /* else, pick up where we left off */

    if (++recursive == 30) {
    print("alias references too many addresses!\n");
    recursive = 0;
    return NULL;
    }
    do  {
    if (!(p = get_name_n_addr(s, NULL, NULL)))
        break;
    c = *p, *p = 0;

    /* if this is an alias, recurse this routine to expand it out */
    if ((tmp = do_set(aliases, s)) && *tmp) {
        if (!alias_to_address(strcpy(newbuf, tmp))) {
        *p = c;
        return NULL;
        } else
        p2 = buf+strlen(buf);
    /* Now, make sure the buffer doesn't overflow */
    } else if (strlen(s) + (p2-buf) + 2 > BUFSIZ) {  /* add " "  + NULL */
        print("address length too long.\n");
        recursive = 0;
        *p = c;
        return NULL;
    } else {
        /* append the new alias (or unchanged address) onto the buffer */
        p2 += Strcpy(p2, s);
        *p2++ = ',', *p2++ = ' ';
    }
    for (*p = c; *p == ',' || isspace(*p); p++)
        ;
    } while (*(s = p));
    if (recursive)
    recursive--;
    if (!recursive)
    *(p2-2) = 0;  /* get rid of last ", " if end of recursion */
    return buf;
}