/*-
 * SPDX-License-Identifier: BSD-1-Clause
 *
 * Copyright 2012 Konstantin Belousov <kib@FreeBSD.org>
 * Copyright (c) 2018, 2023 The FreeBSD Foundation
 *
 * Parts of this software was developed by Konstantin Belousov
 * <kib@FreeBSD.org> under sponsorship from the FreeBSD Foundation.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/param.h>
#include <sys/elf.h>
#include <sys/elf_common.h>
#include <errno.h>
#include <stdlib.h>
#include "libc_private.h"

extern void (*__preinit_array_start[])(int, char **, char **) __hidden;
extern void (*__preinit_array_end[])(int, char **, char **) __hidden;
extern void (*__init_array_start[])(int, char **, char **) __hidden;
extern void (*__init_array_end[])(int, char **, char **) __hidden;
extern void (*__fini_array_start[])(void) __hidden;
extern void (*__fini_array_end[])(void) __hidden;
extern void _fini(void) __hidden;
extern void _init(void) __hidden;

extern int _DYNAMIC;
#pragma weak _DYNAMIC

#if defined(CRT_IRELOC_RELA)
extern const Elf_Rela __rela_iplt_start[] __weak_symbol __hidden;
extern const Elf_Rela __rela_iplt_end[] __weak_symbol __hidden;

#include "reloc.c"

static void
process_irelocs(void)
{
        const Elf_Rela *r;

        for (r = &__rela_iplt_start[0]; r < &__rela_iplt_end[0]; r++)
                crt1_handle_rela(r);
}
#elif defined(CRT_IRELOC_REL)
extern const Elf_Rel __rel_iplt_start[] __weak_symbol __hidden;
extern const Elf_Rel __rel_iplt_end[] __weak_symbol __hidden;

#include "reloc.c"

static void
process_irelocs(void)
{
        const Elf_Rel *r;

        for (r = &__rel_iplt_start[0]; r < &__rel_iplt_end[0]; r++)
                crt1_handle_rel(r);
}
#elif defined(CRT_IRELOC_SUPPRESS)
#else
#error "Define platform reloc type"
#endif

#ifndef PIC
static void
finalizer(void)
{
        void (*fn)(void);
        size_t array_size, n;

        array_size = __fini_array_end - __fini_array_start;
        for (n = array_size; n > 0; n--) {
                fn = __fini_array_start[n - 1];
                if ((uintptr_t)fn != 0 && (uintptr_t)fn != 1)
                        (fn)();
        }
        _fini();
}
#endif

static void
handle_static_init(int argc, char **argv, char **env)
{
#ifndef PIC
        void (*fn)(int, char **, char **);
        size_t array_size, n;

        if (&_DYNAMIC != NULL)
                return;

        atexit(finalizer);

        array_size = __preinit_array_end - __preinit_array_start;
        for (n = 0; n < array_size; n++) {
                fn = __preinit_array_start[n];
                if ((uintptr_t)fn != 0 && (uintptr_t)fn != 1)
                        fn(argc, argv, env);
        }
        _init();
        array_size = __init_array_end - __init_array_start;
        for (n = 0; n < array_size; n++) {
                fn = __init_array_start[n];
                if ((uintptr_t)fn != 0 && (uintptr_t)fn != 1)
                        fn(argc, argv, env);
        }
#endif
}

static void
handle_argv(int argc, char *argv[], char **env)
{
        const char *s;

        if (environ == NULL)
                environ = env;
        if (argc > 0 && argv[0] != NULL) {
                __progname = argv[0];
                for (s = __progname; *s != '\0'; s++) {
                        if (*s == '/')
                                __progname = s + 1;
                }
        }
}

static void
handle_irelocs(char *env[])
{
#ifndef CRT_IRELOC_SUPPRESS
        const Elf_Auxinfo *aux;

        /* Find the auxiliary vector on the stack. */
        while (*env++ != 0)     /* Skip over environment, and NULL terminator */
                ;
        aux = (const Elf_Auxinfo *)env;

        ifunc_init(aux);
        process_irelocs();
#else
        (void)env;
#endif
}

void
__libc_start1(int argc, char *argv[], char *env[], void (*cleanup)(void),
    int (*mainX)(int, char *[], char *[]))
{
        handle_argv(argc, argv, env);

        if (&_DYNAMIC != NULL) {
                atexit(cleanup);
        } else {
                handle_irelocs(env);
                _init_tls();
        }

        handle_static_init(argc, argv, env);

        /*
         * C17 4.3 paragraph 3:
         * The value of errno in the initial thread is zero at program
         * startup.
         */
        errno = 0;
        exit(mainX(argc, argv, env));
}

/* XXXKIB _mcleanup and monstartup defs */
extern void _mcleanup(void);
extern void monstartup(void *, void *);

void
__libc_start1_gcrt(int argc, char *argv[], char *env[],
    void (*cleanup)(void), int (*mainX)(int, char *[], char *[]),
    int *eprolp, int *etextp)
{
        handle_argv(argc, argv, env);

        if (&_DYNAMIC != NULL) {
                atexit(cleanup);
        } else {
                handle_irelocs(env);
                _init_tls();
        }

        atexit(_mcleanup);
        monstartup(eprolp, etextp);

        handle_static_init(argc, argv, env);
        errno = 0;
        exit(mainX(argc, argv, env));
}