// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright (c) 2011 The Chromium OS Authors.
 */

#define _GNU_SOURCE

#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
#include <setjmp.h>
#include <signal.h>
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <termios.h>
#include <time.h>
#include <ucontext.h>
#include <unistd.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/types.h>
#include <linux/compiler_attributes.h>
#include <linux/types.h>

#include <asm/getopt.h>
#include <asm/sections.h>
#include <asm/state.h>
#include <os.h>
#include <rtc_def.h>

/* Environment variable for time offset */
#define ENV_TIME_OFFSET "UBOOT_SB_TIME_OFFSET"

/* Operating System Interface */

struct os_mem_hdr {
        size_t length;          /* number of bytes in the block */
};

ssize_t os_read(int fd, void *buf, size_t count)
{
        return read(fd, buf, count);
}

ssize_t os_write(int fd, const void *buf, size_t count)
{
        return write(fd, buf, count);
}

off_t os_lseek(int fd, off_t offset, int whence)
{
        if (whence == OS_SEEK_SET)
                whence = SEEK_SET;
        else if (whence == OS_SEEK_CUR)
                whence = SEEK_CUR;
        else if (whence == OS_SEEK_END)
                whence = SEEK_END;
        else
                os_exit(1);
        return lseek(fd, offset, whence);
}

int os_open(const char *pathname, int os_flags)
{
        int flags;

        switch (os_flags & OS_O_MASK) {
        case OS_O_RDONLY:
        default:
                flags = O_RDONLY;
                break;

        case OS_O_WRONLY:
                flags = O_WRONLY;
                break;

        case OS_O_RDWR:
                flags = O_RDWR;
                break;
        }

        if (os_flags & OS_O_CREAT)
                flags |= O_CREAT;
        if (os_flags & OS_O_TRUNC)
                flags |= O_TRUNC;
        /*
         * During a cold reset execv() is used to relaunch the U-Boot binary.
         * We must ensure that all files are closed in this case.
         */
        flags |= O_CLOEXEC;

        return open(pathname, flags, 0777);
}

int os_close(int fd)
{
        /* Do not close the console input */
        if (fd)
                return close(fd);
        return -1;
}

int os_unlink(const char *pathname)
{
        return unlink(pathname);
}

void os_exit(int exit_code)
{
        exit(exit_code);
}

int os_write_file(const char *fname, const void *buf, int size)
{
        int fd;

        fd = os_open(fname, OS_O_WRONLY | OS_O_CREAT | OS_O_TRUNC);
        if (fd < 0) {
                printf("Cannot open file '%s'\n", fname);
                return -EIO;
        }
        if (os_write(fd, buf, size) != size) {
                printf("Cannot write to file '%s'\n", fname);
                os_close(fd);
                return -EIO;
        }
        os_close(fd);

        return 0;
}

int os_filesize(int fd)
{
        off_t size;

        size = os_lseek(fd, 0, OS_SEEK_END);
        if (size < 0)
                return -errno;
        if (os_lseek(fd, 0, OS_SEEK_SET) < 0)
                return -errno;

        return size;
}

int os_read_file(const char *fname, void **bufp, int *sizep)
{
        off_t size;
        int ret = -EIO;
        int fd;

        fd = os_open(fname, OS_O_RDONLY);
        if (fd < 0) {
                printf("Cannot open file '%s'\n", fname);
                goto err;
        }
        size = os_filesize(fd);
        if (size < 0) {
                printf("Cannot get file size of '%s'\n", fname);
                goto err;
        }

        *bufp = os_malloc(size);
        if (!*bufp) {
                printf("Not enough memory to read file '%s'\n", fname);
                ret = -ENOMEM;
                goto err;
        }
        if (os_read(fd, *bufp, size) != size) {
                printf("Cannot read from file '%s'\n", fname);
                goto err;
        }
        os_close(fd);
        *sizep = size;

        return 0;
err:
        os_close(fd);
        return ret;
}

int os_map_file(const char *pathname, int os_flags, void **bufp, int *sizep)
{
        void *ptr;
        int size;
        int ifd;

        ifd = os_open(pathname, os_flags);
        if (ifd < 0) {
                printf("Cannot open file '%s'\n", pathname);
                return -EIO;
        }
        size = os_filesize(ifd);
        if (size < 0) {
                printf("Cannot get file size of '%s'\n", pathname);
                return -EIO;
        }

        ptr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, ifd, 0);
        if (ptr == MAP_FAILED) {
                printf("Can't map file '%s': %s\n", pathname, strerror(errno));
                return -EPERM;
        }

        *bufp = ptr;
        *sizep = size;

        return 0;
}

/* Restore tty state when we exit */
static struct termios orig_term;
static bool term_setup;
static bool term_nonblock;

void os_fd_restore(void)
{
        if (term_setup) {
                int flags;

                tcsetattr(0, TCSANOW, &orig_term);
                if (term_nonblock) {
                        flags = fcntl(0, F_GETFL, 0);
                        fcntl(0, F_SETFL, flags & ~O_NONBLOCK);
                }
                term_setup = false;
        }
}

static void os_sigint_handler(int sig)
{
        os_fd_restore();
        signal(SIGINT, SIG_DFL);
        raise(SIGINT);
}

static void os_signal_handler(int sig, siginfo_t *info, void *con)
{
        ucontext_t __maybe_unused *context = con;
        unsigned long pc;

#if defined(__x86_64__)
        pc = context->uc_mcontext.gregs[REG_RIP];
#elif defined(__aarch64__)
        pc = context->uc_mcontext.pc;
#elif defined(__riscv)
        pc = context->uc_mcontext.__gregs[REG_PC];
#else
        const char msg[] =
                "\nUnsupported architecture, cannot read program counter\n";

        os_write(1, msg, sizeof(msg));
        pc = 0;
#endif

        os_signal_action(sig, pc);
}

int os_setup_signal_handlers(void)
{
        struct sigaction act;

        act.sa_sigaction = os_signal_handler;
        sigemptyset(&act.sa_mask);
        act.sa_flags = SA_SIGINFO;
        if (sigaction(SIGILL, &act, NULL) ||
            sigaction(SIGBUS, &act, NULL) ||
            sigaction(SIGSEGV, &act, NULL))
                return -1;
        return 0;
}

/* Put tty into raw mode so <tab> and <ctrl+c> work */
void os_tty_raw(int fd, bool allow_sigs)
{
        struct termios term;
        int flags;

        if (term_setup)
                return;

        /* If not a tty, don't complain */
        if (tcgetattr(fd, &orig_term))
                return;

        term = orig_term;
        term.c_iflag = IGNBRK | IGNPAR;
        term.c_oflag = OPOST | ONLCR;
        term.c_cflag = CS8 | CREAD | CLOCAL;
        term.c_lflag = allow_sigs ? ISIG : 0;
        if (tcsetattr(fd, TCSANOW, &term))
                return;

        flags = fcntl(fd, F_GETFL, 0);
        if (!(flags & O_NONBLOCK)) {
                if (fcntl(fd, F_SETFL, flags | O_NONBLOCK))
                        return;
                term_nonblock = true;
        }

        term_setup = true;
        atexit(os_fd_restore);
        signal(SIGINT, os_sigint_handler);
}

/*
 * Provide our own malloc so we don't use space in the sandbox ram_buf for
 * allocations that are internal to sandbox, or need to be done before U-Boot's
 * malloc() is ready.
 */
void *os_malloc(size_t length)
{
        int page_size = getpagesize();
        struct os_mem_hdr *hdr;

        if (!length)
                return NULL;
        /*
         * Use an address that is hopefully available to us so that pointers
         * to this memory are fairly obvious. If we end up with a different
         * address, that's fine too.
         */
        hdr = mmap((void *)0x10000000, length + page_size,
                   PROT_READ | PROT_WRITE | PROT_EXEC,
                   MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
        if (hdr == MAP_FAILED)
                return NULL;
        hdr->length = length;

        return (void *)hdr + page_size;
}

void os_free(void *ptr)
{
        int page_size = getpagesize();
        struct os_mem_hdr *hdr;

        if (ptr) {
                hdr = ptr - page_size;
                munmap(hdr, hdr->length + page_size);
        }
}

/* These macros are from kernel.h but not accessible in this file */
#define ALIGN(x, a)             __ALIGN_MASK((x), (typeof(x))(a) - 1)
#define __ALIGN_MASK(x, mask)   (((x) + (mask)) & ~(mask))

/*
 * Provide our own malloc so we don't use space in the sandbox ram_buf for
 * allocations that are internal to sandbox, or need to be done before U-Boot's
 * malloc() is ready.
 */
void *os_realloc(void *ptr, size_t length)
{
        int page_size = getpagesize();
        struct os_mem_hdr *hdr;
        void *new_ptr;

        /* Reallocating a NULL pointer is just an alloc */
        if (!ptr)
                return os_malloc(length);

        /* Changing a length to 0 is just a free */
        if (length) {
                os_free(ptr);
                return NULL;
        }

        /*
         * If the new size is the same number of pages as the old, nothing to
         * do. There isn't much point in shrinking things
         */
        hdr = ptr - page_size;
        if (ALIGN(length, page_size) <= ALIGN(hdr->length, page_size))
                return ptr;

        /* We have to grow it, so allocate something new */
        new_ptr = os_malloc(length);
        memcpy(new_ptr, ptr, hdr->length);
        os_free(ptr);

        return new_ptr;
}

void os_usleep(unsigned long usec)
{
        usleep(usec);
}

uint64_t __attribute__((no_instrument_function)) os_get_nsec(void)
{
#if defined(CLOCK_MONOTONIC) && defined(_POSIX_MONOTONIC_CLOCK)
        struct timespec tp;
        if (EINVAL == clock_gettime(CLOCK_MONOTONIC, &tp)) {
                struct timeval tv;

                gettimeofday(&tv, NULL);
                tp.tv_sec = tv.tv_sec;
                tp.tv_nsec = tv.tv_usec * 1000;
        }
        return tp.tv_sec * 1000000000ULL + tp.tv_nsec;
#else
        struct timeval tv;
        gettimeofday(&tv, NULL);
        return tv.tv_sec * 1000000000ULL + tv.tv_usec * 1000;
#endif
}

static char *short_opts;
static struct option *long_opts;

int os_parse_args(struct sandbox_state *state, int argc, char *argv[])
{
        struct sandbox_cmdline_option **sb_opt =
                __u_boot_sandbox_option_start();
        size_t num_options = __u_boot_sandbox_option_count();
        size_t i;

        int hidden_short_opt;
        size_t si;

        int c;

        if (short_opts || long_opts)
                return 1;

        state->argc = argc;
        state->argv = argv;

        /* dynamically construct the arguments to the system getopt_long */
        short_opts = os_malloc(sizeof(*short_opts) * num_options * 2 + 1);
        long_opts = os_malloc(sizeof(*long_opts) * (num_options + 1));
        if (!short_opts || !long_opts)
                return 1;

        /*
         * getopt_long requires "val" to be unique (since that is what the
         * func returns), so generate unique values automatically for flags
         * that don't have a short option.  pick 0x100 as that is above the
         * single byte range (where ASCII/ISO-XXXX-X charsets live).
         */
        hidden_short_opt = 0x100;
        si = 0;
        for (i = 0; i < num_options; ++i) {
                long_opts[i].name = sb_opt[i]->flag;
                long_opts[i].has_arg = sb_opt[i]->has_arg ?
                        required_argument : no_argument;
                long_opts[i].flag = NULL;

                if (sb_opt[i]->flag_short) {
                        short_opts[si++] = long_opts[i].val = sb_opt[i]->flag_short;
                        if (long_opts[i].has_arg == required_argument)
                                short_opts[si++] = ':';
                } else
                        long_opts[i].val = sb_opt[i]->flag_short = hidden_short_opt++;
        }
        short_opts[si] = '\0';

        /* we need to handle output ourselves since u-boot provides printf */
        opterr = 0;

        memset(&long_opts[num_options], '\0', sizeof(*long_opts));
        /*
         * walk all of the options the user gave us on the command line,
         * figure out what u-boot option structure they belong to (via
         * the unique short val key), and call the appropriate callback.
         */
        while ((c = getopt_long(argc, argv, short_opts, long_opts, NULL)) != -1) {
                for (i = 0; i < num_options; ++i) {
                        if (sb_opt[i]->flag_short == c) {
                                if (sb_opt[i]->callback(state, optarg)) {
                                        state->parse_err = sb_opt[i]->flag;
                                        return 0;
                                }
                                break;
                        }
                }
                if (i == num_options) {
                        /*
                         * store the faulting flag for later display.  we have to
                         * store the flag itself as the getopt parsing itself is
                         * tricky: need to handle the following flags (assume all
                         * of the below are unknown):
                         *   -a        optopt='a' optind=<next>
                         *   -abbbb    optopt='a' optind=<this>
                         *   -aaaaa    optopt='a' optind=<this>
                         *   --a       optopt=0   optind=<this>
                         * as you can see, it is impossible to determine the exact
                         * faulting flag without doing the parsing ourselves, so
                         * we just report the specific flag that failed.
                         */
                        if (optopt) {
                                static char parse_err[3] = { '-', 0, '\0', };
                                parse_err[1] = optopt;
                                state->parse_err = parse_err;
                        } else
                                state->parse_err = argv[optind - 1];
                        break;
                }
        }

        return 0;
}

void os_dirent_free(struct os_dirent_node *node)
{
        struct os_dirent_node *next;

        while (node) {
                next = node->next;
                os_free(node);
                node = next;
        }
}

int os_dirent_ls(const char *dirname, struct os_dirent_node **headp)
{
        struct dirent *entry;
        struct os_dirent_node *head, *node, *next;
        struct stat buf;
        DIR *dir;
        int ret;
        char *fname;
        char *old_fname;
        int len;
        int dirlen;

        *headp = NULL;
        dir = opendir(dirname);
        if (!dir)
                return -1;

        /* Create a buffer upfront, with typically sufficient size */
        dirlen = strlen(dirname) + 2;
        len = dirlen + 256;
        fname = os_malloc(len);
        if (!fname) {
                ret = -ENOMEM;
                goto done;
        }

        for (node = head = NULL;; node = next) {
                errno = 0;
                entry = readdir(dir);
                if (!entry) {
                        ret = errno;
                        break;
                }
                next = os_malloc(sizeof(*node) + strlen(entry->d_name) + 1);
                if (!next) {
                        os_dirent_free(head);
                        ret = -ENOMEM;
                        goto done;
                }
                if (dirlen + strlen(entry->d_name) > len) {
                        len = dirlen + strlen(entry->d_name);
                        old_fname = fname;
                        fname = os_realloc(fname, len);
                        if (!fname) {
                                os_free(old_fname);
                                os_free(next);
                                os_dirent_free(head);
                                ret = -ENOMEM;
                                goto done;
                        }
                }
                next->next = NULL;
                strcpy(next->name, entry->d_name);
                switch (entry->d_type) {
                case DT_REG:
                        next->type = OS_FILET_REG;
                        break;
                case DT_DIR:
                        next->type = OS_FILET_DIR;
                        break;
                case DT_LNK:
                        next->type = OS_FILET_LNK;
                        break;
                default:
                        next->type = OS_FILET_UNKNOWN;
                }
                next->size = 0;
                snprintf(fname, len, "%s/%s", dirname, next->name);
                if (!stat(fname, &buf))
                        next->size = buf.st_size;
                if (node)
                        node->next = next;
                else
                        head = next;
        }
        *headp = head;

done:
        closedir(dir);
        os_free(fname);
        return ret;
}

const char *os_dirent_typename[OS_FILET_COUNT] = {
        "   ",
        "SYM",
        "DIR",
        "???",
};

const char *os_dirent_get_typename(enum os_dirent_t type)
{
        if (type >= OS_FILET_REG && type < OS_FILET_COUNT)
                return os_dirent_typename[type];

        return os_dirent_typename[OS_FILET_UNKNOWN];
}

int os_get_filesize(const char *fname, loff_t *size)
{
        struct stat buf;
        int ret;

        ret = stat(fname, &buf);
        if (ret)
                return ret;
        *size = buf.st_size;
        return 0;
}

void os_putc(int ch)
{
        putchar(ch);
}

void os_puts(const char *str)
{
        while (*str)
                os_putc(*str++);
}

int os_write_ram_buf(const char *fname)
{
        struct sandbox_state *state = state_get_current();
        int fd, ret;

        fd = open(fname, O_CREAT | O_WRONLY, 0777);
        if (fd < 0)
                return -ENOENT;
        ret = write(fd, state->ram_buf, state->ram_size);
        close(fd);
        if (ret != state->ram_size)
                return -EIO;

        return 0;
}

int os_read_ram_buf(const char *fname)
{
        struct sandbox_state *state = state_get_current();
        int fd, ret;
        loff_t size;

        ret = os_get_filesize(fname, &size);
        if (ret < 0)
                return ret;
        if (size != state->ram_size)
                return -ENOSPC;
        fd = open(fname, O_RDONLY);
        if (fd < 0)
                return -ENOENT;

        ret = read(fd, state->ram_buf, state->ram_size);
        close(fd);
        if (ret != state->ram_size)
                return -EIO;

        return 0;
}

static int make_exec(char *fname, const void *data, int size)
{
        int fd;

        strcpy(fname, "/tmp/u-boot.jump.XXXXXX");
        fd = mkstemp(fname);
        if (fd < 0)
                return -ENOENT;
        if (write(fd, data, size) < 0)
                return -EIO;
        close(fd);
        if (chmod(fname, 0777))
                return -ENOEXEC;

        return 0;
}

/**
 * add_args() - Allocate a new argv with the given args
 *
 * This is used to create a new argv array with all the old arguments and some
 * new ones that are passed in
 *
 * @argvp:  Returns newly allocated args list
 * @add_args: Arguments to add, each a string
 * @count: Number of arguments in @add_args
 * @return 0 if OK, -ENOMEM if out of memory
 */
static int add_args(char ***argvp, char *add_args[], int count)
{
        char **argv, **ap;
        int argc;

        for (argc = 0; (*argvp)[argc]; argc++)
                ;

        argv = os_malloc((argc + count + 1) * sizeof(char *));
        if (!argv) {
                printf("Out of memory for %d argv\n", count);
                return -ENOMEM;
        }
        for (ap = *argvp, argc = 0; *ap; ap++) {
                char *arg = *ap;

                /* Drop args that we don't want to propagate */
                if (*arg == '-' && strlen(arg) == 2) {
                        switch (arg[1]) {
                        case 'j':
                        case 'm':
                                ap++;
                                continue;
                        }
                } else if (!strcmp(arg, "--rm_memory")) {
                        continue;
                }
                argv[argc++] = arg;
        }

        memcpy(argv + argc, add_args, count * sizeof(char *));
        argv[argc + count] = NULL;

        *argvp = argv;
        return 0;
}

/**
 * os_jump_to_file() - Jump to a new program
 *
 * This saves the memory buffer, sets up arguments to the new process, then
 * execs it.
 *
 * @fname: Filename to exec
 * @return does not return on success, any return value is an error
 */
static int os_jump_to_file(const char *fname, bool delete_it)
{
        struct sandbox_state *state = state_get_current();
        char mem_fname[30];
        int fd, err;
        char *extra_args[5];
        char **argv = state->argv;
        int argc;
#ifdef DEBUG
        int i;
#endif

        strcpy(mem_fname, "/tmp/u-boot.mem.XXXXXX");
        fd = mkstemp(mem_fname);
        if (fd < 0)
                return -ENOENT;
        close(fd);
        err = os_write_ram_buf(mem_fname);
        if (err)
                return err;

        os_fd_restore();

        argc = 0;
        if (delete_it) {
                extra_args[argc++] = "-j";
                extra_args[argc++] = (char *)fname;
        }
        extra_args[argc++] = "-m";
        extra_args[argc++] = mem_fname;
        if (state->ram_buf_rm)
                extra_args[argc++] = "--rm_memory";
        err = add_args(&argv, extra_args, argc);
        if (err)
                return err;
        argv[0] = (char *)fname;

#ifdef DEBUG
        for (i = 0; argv[i]; i++)
                printf("%d %s\n", i, argv[i]);
#endif

        if (state_uninit())
                os_exit(2);

        err = execv(fname, argv);
        os_free(argv);
        if (err) {
                perror("Unable to run image");
                printf("Image filename '%s'\n", fname);
                return err;
        }

        if (delete_it)
                return unlink(fname);

        return -EFAULT;
}

int os_jump_to_image(const void *dest, int size)
{
        char fname[30];
        int err;

        err = make_exec(fname, dest, size);
        if (err)
                return err;

        return os_jump_to_file(fname, true);
}

int os_find_u_boot(char *fname, int maxlen, bool use_img,
                   const char *cur_prefix, const char *next_prefix)
{
        struct sandbox_state *state = state_get_current();
        const char *progname = state->argv[0];
        int len = strlen(progname);
        char subdir[10];
        char *suffix;
        char *p;
        int fd;

        if (len >= maxlen || len < 4)
                return -ENOSPC;

        strcpy(fname, progname);
        suffix = fname + len - 4;

        /* Change the existing suffix to the new one */
        if (*suffix != '-')
                return -EINVAL;

        if (*next_prefix)
                strcpy(suffix + 1, next_prefix);  /* e.g. "-tpl" to "-spl" */
        else
                *suffix = '\0';  /* e.g. "-spl" to "" */
        fd = os_open(fname, O_RDONLY);
        if (fd >= 0) {
                close(fd);
                return 0;
        }

        /*
         * We didn't find it, so try looking for 'u-boot-xxx' in the xxx/
         * directory. Replace the old dirname with the new one.
         */
        snprintf(subdir, sizeof(subdir), "/%s/", cur_prefix);
        p = strstr(fname, subdir);
        if (p) {
                if (*next_prefix)
                        /* e.g. ".../tpl/u-boot-spl"  to "../spl/u-boot-spl" */
                        memcpy(p + 1, next_prefix, strlen(next_prefix));
                else
                        /* e.g. ".../spl/u-boot" to ".../u-boot" */
                        strcpy(p, p + 1 + strlen(cur_prefix));
                if (use_img)
                        strcat(p, ".img");

                fd = os_open(fname, O_RDONLY);
                if (fd >= 0) {
                        close(fd);
                        return 0;
                }
        }

        return -ENOENT;
}

int os_spl_to_uboot(const char *fname)
{
        struct sandbox_state *state = state_get_current();

        /* U-Boot will delete ram buffer after read: "--rm_memory"*/
        state->ram_buf_rm = true;

        return os_jump_to_file(fname, false);
}

long os_get_time_offset(void)
{
        const char *offset;

        offset = getenv(ENV_TIME_OFFSET);
        if (offset)
                return strtol(offset, NULL, 0);
        return 0;
}

void os_set_time_offset(long offset)
{
        char buf[21];
        int ret;

        snprintf(buf, sizeof(buf), "%ld", offset);
        ret = setenv(ENV_TIME_OFFSET, buf, true);
        if (ret)
                printf("Could not set environment variable %s\n",
                       ENV_TIME_OFFSET);
}

void os_localtime(struct rtc_time *rt)
{
        time_t t = time(NULL);
        struct tm *tm;

        tm = localtime(&t);
        rt->tm_sec = tm->tm_sec;
        rt->tm_min = tm->tm_min;
        rt->tm_hour = tm->tm_hour;
        rt->tm_mday = tm->tm_mday;
        rt->tm_mon = tm->tm_mon + 1;
        rt->tm_year = tm->tm_year + 1900;
        rt->tm_wday = tm->tm_wday;
        rt->tm_yday = tm->tm_yday;
        rt->tm_isdst = tm->tm_isdst;
}

void os_abort(void)
{
        abort();
}

int os_mprotect_allow(void *start, size_t len)
{
        int page_size = getpagesize();

        /* Move start to the start of a page, len to the end */
        start = (void *)(((ulong)start) & ~(page_size - 1));
        len = (len + page_size * 2) & ~(page_size - 1);

        return mprotect(start, len, PROT_READ | PROT_WRITE);
}

void *os_find_text_base(void)
{
        char line[500];
        void *base = NULL;
        int len;
        int fd;

        /*
         * This code assumes that the first line of /proc/self/maps holds
         * information about the text, for example:
         *
         * 5622d9907000-5622d9a55000 r-xp 00000000 08:01 15067168   u-boot
         *
         * The first hex value is assumed to be the address.
         *
         * This is tested in Linux 4.15.
         */
        fd = open("/proc/self/maps", O_RDONLY);
        if (fd == -1)
                return NULL;
        len = read(fd, line, sizeof(line));
        if (len > 0) {
                char *end = memchr(line, '-', len);

                if (end) {
                        uintptr_t addr;

                        *end = '\0';
                        if (sscanf(line, "%zx", &addr) == 1)
                                base = (void *)addr;
                }
        }
        close(fd);

        return base;
}

void os_relaunch(char *argv[])
{
        execv(argv[0], argv);
        os_exit(1);
}