/*
 * Copyright (c) 1994 University of Maryland
 * All Rights Reserved.
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice appear in all copies and that both that
 * copyright notice and this permission notice appear in supporting
 * documentation, and that the name of U.M. not be used in advertising or
 * publicity pertaining to distribution of the software without specific,
 * written prior permission.  U.M. makes no representations about the
 * suitability of this software for any purpose.  It is provided "as is"
 * without express or implied warranty.
 *
 * U.M. DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL U.M.
 * BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 * Author: James da Silva, Systems Design and Analysis Group
 *                         Computer Science Department
 *                         University of Maryland at College Park
 */
/*
 * crunched_main.c - main program for crunched binaries, it branches to a
 *      particular subprogram based on the value of argv[0].  Also included
 *      is a little program invoked when the crunched binary is called via
 *      its EXECNAME.  This one prints out the list of compiled-in binaries,
 *      or calls one of them based on argv[1].   This allows the testing of
 *      the crunched binary without creating all the links.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <err.h>

struct stub {
        const char *name;
        int (*f)(int, char **, char **);
};

static const struct stub entry_points[];

static int crunched_main(int argc, char **, char **);
static int cmpstringp(const void *, const void *);
static void crunched_usage(void) __dead2;


int
main(int argc, char **argv, char **envp)
{
        const char *slash, *basename;
        const struct stub *ep;

        if (argv[0] == NULL || *argv[0] == '\0')
                crunched_usage();

        slash = strrchr(argv[0], '/');
        basename = slash ? slash+1 : argv[0];

        for (ep = entry_points; ep->name != NULL; ep++)
                if (strcmp(basename, ep->name) == 0)
                        return ep->f(argc, argv, envp);

        fprintf(stderr, "%s: %s not compiled in\n", EXECNAME, basename);
        crunched_usage();
}


static int
crunched_main(int argc, char **argv, char **envp)
{
        if (argc <= 1)
                crunched_usage();

        return main(--argc, ++argv, envp);
}


static int
cmpstringp(const void *p1, const void *p2)
{
        const char *s1 = *(char * const *)p1;
        const char *s2 = *(char * const *)p2;
        return strcmp(s1, s2);
}


__dead2
static void
crunched_usage(void)
{
        int nprog = 0, columns = 0;
        int i, len;
        const struct stub *ep;
        const char **prognames;

        for (ep = entry_points; ep->name != NULL; ep++)
                nprog++;
        if ((prognames = malloc(nprog * sizeof(char *))) == NULL)
                err(EXIT_FAILURE, "malloc");
        for (i = 0; i < nprog; i++)
                prognames[i] = entry_points[i].name;
        qsort(prognames, nprog, sizeof(char *), cmpstringp);

        fprintf(stderr,
                "usage: %s <prog> <args> ..., where <prog> is one of:\n",
                EXECNAME);
        for (i = 0; i < nprog; i++) {
                if (strcmp(EXECNAME, prognames[i]) == 0)
                        continue;
                len = strlen(prognames[i]) + 1;
                if (columns+len < 80)
                        columns += len;
                else {
                        fprintf(stderr, "\n");
                        columns = len;
                }
                fprintf(stderr, " %s", prognames[i]);
        }
        fprintf(stderr, "\n");
        free(prognames);
        exit(1);
}

/* end of crunched_main.c */