/*

   Unix SMB/CIFS implementation.

   replacement routines for broken systems

   Copyright (C) Andrew Tridgell 1992-1998

   Copyright (C) Jelmer Vernooij 2005-2008

   Copyright (C) Matthieu Patou  2010

     ** NOTE! The following LGPL license applies to the replace

     ** library. This does NOT imply that all of Samba is released

     ** under the LGPL

   This library is free software; you can redistribute it and/or

   modify it under the terms of the GNU Lesser General Public

   License as published by the Free Software Foundation; either

   version 3 of the License, or (at your option) any later version.

   This library is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public

   License along with this library; if not, see <http://www.gnu.org/licenses/>.

*/

#include "replace.h"

#include "system/filesys.h"

#include "system/time.h"

#include "system/network.h"

#include "system/passwd.h"

#include "system/syslog.h"

#include "system/locale.h"

#include "system/wait.h"

#ifdef HAVE_SYS_SYSCALL_H

#include <sys/syscall.h>

#endif

#ifdef HAVE_SYS_PRCTL_H

#include <sys/prctl.h>

#endif

#ifdef _WIN32

#define mkdir(d,m) _mkdir(d)

#endif

void replace_dummy(void);

void replace_dummy(void) {}

#ifndef HAVE_FTRUNCATE

 /*******************************************************************

ftruncate for operating systems that don't have it

********************************************************************/

int rep_ftruncate(int f, off_t l)

{

#ifdef HAVE_CHSIZE

      return chsize(f,l);

#elif defined(F_FREESP)

      struct  flock   fl;

      fl.l_whence = 0;

      fl.l_len = 0;

      fl.l_start = l;

      fl.l_type = F_WRLCK;

      return fcntl(f, F_FREESP, &fl);

#else

#error "you must have a ftruncate function"

#endif

}

#endif /* HAVE_FTRUNCATE */

#ifndef HAVE_STRLCPY

/*

 * Like strncpy but does not 0 fill the buffer and always null

 * terminates. bufsize is the size of the destination buffer.

 * Returns the length of s.

 */

size_t rep_strlcpy(char *d, const char *s, size_t bufsize)

{

  size_t len = strlen(s);

  size_t ret = len;

  if (bufsize <= 0) {

    return 0;

  }

  if (len >= bufsize) {

    len = bufsize - 1;

  }

  memcpy(d, s, len);

  d[len] = 0;

  return ret;

}

#endif

#ifndef HAVE_STRLCAT

/* like strncat but does not 0 fill the buffer and always null

   terminates. bufsize is the length of the buffer, which should

   be one more than the maximum resulting string length */

size_t rep_strlcat(char *d, const char *s, size_t bufsize)

{

  size_t len1 = strnlen(d, bufsize);

  size_t len2 = strlen(s);

  size_t ret = len1 + len2;

  if (len1+len2 >= bufsize) {

    if (bufsize < (len1+1)) {

      return ret;

    }

    len2 = bufsize - (len1+1);

  }

  if (len2 > 0) {

    memcpy(d+len1, s, len2);

    d[len1+len2] = 0;

  }

  return ret;

}

#endif

#ifndef HAVE_MKTIME

/*******************************************************************

a mktime() replacement for those who don't have it - contributed by

C.A. Lademann <cal@zls.com>

Corrections by richard.kettlewell@kewill.com

********************************************************************/

#define  MINUTE  60

#define  HOUR    60*MINUTE

#define  DAY             24*HOUR

#define  YEAR    365*DAY

time_t rep_mktime(struct tm *t)

{

  struct tm       *u;

  time_t  epoch = 0;

  int n;

  int             mon [] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },

  y, m, i;

  if(t->tm_year < 70)

    return((time_t)-1);

  n = t->tm_year + 1900 - 1;

  epoch = (t->tm_year - 70) * YEAR +

    ((n / 4 - n / 100 + n / 400) - (1969 / 4 - 1969 / 100 + 1969 / 400)) * DAY;

  y = t->tm_year + 1900;

  m = 0;

  for(i = 0; i < t->tm_mon; i++) {

    epoch += mon [m] * DAY;

    if(m == 1 && y % 4 == 0 && (y % 100 != 0 || y % 400 == 0))

      epoch += DAY;

    if(++m > 11) {

      m = 0;

      y++;

    }

  }

  epoch += (t->tm_mday - 1) * DAY;

  epoch += t->tm_hour * HOUR + t->tm_min * MINUTE + t->tm_sec;

  if((u = localtime(&epoch)) != NULL) {

    t->tm_sec = u->tm_sec;

    t->tm_min = u->tm_min;

    t->tm_hour = u->tm_hour;

    t->tm_mday = u->tm_mday;

    t->tm_mon = u->tm_mon;

    t->tm_year = u->tm_year;

    t->tm_wday = u->tm_wday;

    t->tm_yday = u->tm_yday;

    t->tm_isdst = u->tm_isdst;

  }

  return(epoch);

}

#endif /* !HAVE_MKTIME */

#ifndef HAVE_INITGROUPS

/****************************************************************************

 some systems don't have an initgroups call

****************************************************************************/

int rep_initgroups(char *name, gid_t id)

{

#ifndef HAVE_SETGROUPS

  /* yikes! no SETGROUPS or INITGROUPS? how can this work? */

  errno = ENOSYS;

  return -1;

#else /* HAVE_SETGROUPS */

#include <grp.h>

  gid_t *grouplst = NULL;

  int max_gr = NGROUPS_MAX;

  int ret;

  int    i,j;

  struct group *g;

  char   *gr;

  if((grouplst = malloc(sizeof(gid_t) * max_gr)) == NULL) {

    errno = ENOMEM;

    return -1;

  }

  grouplst[0] = id;

  i = 1;

  while (i < max_gr && ((g = (struct group *)getgrent()) != (struct group *)NULL)) {

    if (g->gr_gid == id)

      continue;

    j = 0;

    gr = g->gr_mem[0];

    while (gr && (*gr != (char)NULL)) {

      if (strcmp(name,gr) == 0) {

        grouplst[i] = g->gr_gid;

        i++;

        gr = (char *)NULL;

        break;

      }

      gr = g->gr_mem[++j];

    }

  }

  endgrent();

  ret = setgroups(i, grouplst);

  free(grouplst);

  return ret;

#endif /* HAVE_SETGROUPS */

}

#endif /* HAVE_INITGROUPS */

#ifndef HAVE_MEMMOVE

/*******************************************************************

safely copies memory, ensuring no overlap problems.

this is only used if the machine does not have its own memmove().

this is not the fastest algorithm in town, but it will do for our

needs.

********************************************************************/

void *rep_memmove(void *dest,const void *src,int size)

{

  unsigned long d,s;

  int i;

  if (dest==src || !size) return(dest);

  d = (unsigned long)dest;

  s = (unsigned long)src;

  if ((d >= (s+size)) || (s >= (d+size))) {

    /* no overlap */

    memcpy(dest,src,size);

    return(dest);

  }

  if (d < s) {

    /* we can forward copy */

    if (s-d >= sizeof(int) &&

        !(s%sizeof(int)) &&

        !(d%sizeof(int)) &&

        !(size%sizeof(int))) {

      /* do it all as words */

      int *idest = (int *)dest;

      int *isrc = (int *)src;

      size /= sizeof(int);

      for (i=0;i<size;i++) idest[i] = isrc[i];

    } else {

      /* simplest */

      char *cdest = (char *)dest;

      char *csrc = (char *)src;

      for (i=0;i<size;i++) cdest[i] = csrc[i];

    }

  } else {

    /* must backward copy */

    if (d-s >= sizeof(int) &&

        !(s%sizeof(int)) &&

        !(d%sizeof(int)) &&

        !(size%sizeof(int))) {

      /* do it all as words */

      int *idest = (int *)dest;

      int *isrc = (int *)src;

      size /= sizeof(int);

      for (i=size-1;i>=0;i--) idest[i] = isrc[i];

    } else {

      /* simplest */

      char *cdest = (char *)dest;

      char *csrc = (char *)src;

      for (i=size-1;i>=0;i--) cdest[i] = csrc[i];

    }

  }

  return(dest);

}

#endif /* HAVE_MEMMOVE */

#ifndef HAVE_STRDUP

/****************************************************************************

duplicate a string

****************************************************************************/

char *rep_strdup(const char *s)

{

  size_t len;

  char *ret;

  if (!s) return(NULL);

  len = strlen(s)+1;

  ret = (char *)malloc(len);

  if (!ret) return(NULL);

  memcpy(ret,s,len);

  return(ret);

}

#endif /* HAVE_STRDUP */

#ifndef HAVE_SETLINEBUF

void rep_setlinebuf(FILE *stream)

{

  setvbuf(stream, (char *)NULL, _IOLBF, 0);

}

#endif /* HAVE_SETLINEBUF */

#ifndef HAVE_VSYSLOG

#ifdef HAVE_SYSLOG

void rep_vsyslog (int facility_priority, const char *format, va_list arglist)

{

  char *msg = NULL;

  vasprintf(&msg, format, arglist);

  if (!msg)

    return;

  syslog(facility_priority, "%s", msg);

  free(msg);

}

#endif /* HAVE_SYSLOG */

#endif /* HAVE_VSYSLOG */

#ifndef HAVE_STRNLEN

/**

 Some platforms don't have strnlen

**/

 size_t rep_strnlen(const char *s, size_t max)

{

        size_t len;

        for (len = 0; len < max; len++) {

                if (s[len] == '\0') {

                        break;

                }

        }

        return len;

}

#endif

#ifndef HAVE_STRNDUP

/**

 Some platforms don't have strndup.

**/

char *rep_strndup(const char *s, size_t n)

{

  char *ret;

  n = strnlen(s, n);

  ret = malloc(n+1);

  if (!ret)

    return NULL;

  memcpy(ret, s, n);

  ret[n] = 0;

  return ret;

}

#endif

#if !defined(HAVE_WAITPID) && defined(HAVE_WAIT4)

int rep_waitpid(pid_t pid,int *status,int options)

{

  return wait4(pid, status, options, NULL);

}

#endif

#ifndef HAVE_SETEUID

int rep_seteuid(uid_t euid)

{

#ifdef HAVE_SETRESUID

  return setresuid(-1, euid, -1);

#else

  errno = ENOSYS;

  return -1;

#endif

}

#endif

#ifndef HAVE_SETEGID

int rep_setegid(gid_t egid)

{

#ifdef HAVE_SETRESGID

  return setresgid(-1, egid, -1);

#else

  errno = ENOSYS;

  return -1;

#endif

}

#endif

/*******************************************************************

os/2 also doesn't have chroot

********************************************************************/

#ifndef HAVE_CHROOT

int rep_chroot(const char *dname)

{

  errno = ENOSYS;

  return -1;

}

#endif

/*****************************************************************

 Possibly replace mkstemp if it is broken.

*****************************************************************/

#ifndef HAVE_SECURE_MKSTEMP

int rep_mkstemp(char *template)

{

  /* have a reasonable go at emulating it. Hope that

     the system mktemp() isn't completely hopeless */

  mktemp(template);

  if (template[0] == 0)

    return -1;

  return open(template, O_CREAT|O_EXCL|O_RDWR, 0600);

}

#endif

#ifndef HAVE_MKDTEMP

char *rep_mkdtemp(char *template)

{

  char *dname;

  if ((dname = mktemp(template))) {

    if (mkdir(dname, 0700) >= 0) {

      return dname;

    }

  }

  return NULL;

}

#endif

/*****************************************************************

 Watch out: this is not thread safe.

*****************************************************************/

#ifndef HAVE_PREAD

ssize_t rep_pread(int __fd, void *__buf, size_t __nbytes, off_t __offset)

{

  if (lseek(__fd, __offset, SEEK_SET) != __offset) {

    return -1;

  }

  return read(__fd, __buf, __nbytes);

}

#endif

/*****************************************************************

 Watch out: this is not thread safe.

*****************************************************************/

#ifndef HAVE_PWRITE

ssize_t rep_pwrite(int __fd, const void *__buf, size_t __nbytes, off_t __offset)

{

  if (lseek(__fd, __offset, SEEK_SET) != __offset) {

    return -1;

  }

  return write(__fd, __buf, __nbytes);

}

#endif

#ifndef HAVE_STRCASESTR

char *rep_strcasestr(const char *haystack, const char *needle)

{

  const char *s;

  size_t nlen = strlen(needle);

  for (s=haystack;*s;s++) {

    if (toupper(*needle) == toupper(*s) &&

        strncasecmp(s, needle, nlen) == 0) {

      return (char *)((uintptr_t)s);

    }

  }

  return NULL;

}

#endif

#ifndef HAVE_STRSEP

char *rep_strsep(char **pps, const char *delim)

{

  char *ret = *pps;

  char *p = *pps;

  if (p == NULL) {

    return NULL;

  }

  p += strcspn(p, delim);

  if (*p == '\0') {

    *pps = NULL;

  } else {

    *p = '\0';

    *pps = p + 1;

  }

  return ret;

}

#endif

#ifndef HAVE_STRTOK_R

/* based on GLIBC version, copyright Free Software Foundation */

char *rep_strtok_r(char *s, const char *delim, char **save_ptr)

{

  char *token;

  if (s == NULL) s = *save_ptr;

  s += strspn(s, delim);

  if (*s == '\0') {

    *save_ptr = s;

    return NULL;

  }

  token = s;

  s = strpbrk(token, delim);

  if (s == NULL) {

    *save_ptr = token + strlen(token);

  } else {

    *s = '\0';

    *save_ptr = s + 1;

  }

  return token;

}

#endif

#ifndef HAVE_STRTOLL

long long int rep_strtoll(const char *str, char **endptr, int base)

{

#ifdef HAVE_STRTOQ

  return strtoq(str, endptr, base);

#elif defined(HAVE___STRTOLL)

  return __strtoll(str, endptr, base);

#elif SIZEOF_LONG == SIZEOF_LONG_LONG

  return (long long int) strtol(str, endptr, base);

#else

# error "You need a strtoll function"

#endif

}

#else

#ifdef HAVE_BSD_STRTOLL

#undef strtoll

long long int rep_strtoll(const char *str, char **endptr, int base)

{

  int saved_errno = errno;

  long long int nb = strtoll(str, endptr, base);

  /* With glibc EINVAL is only returned if base is not ok */

  if (errno == EINVAL) {

    if (base == 0 || (base >1 && base <37)) {

      /* Base was ok so it's because we were not

       * able to make the conversion.

       * Let's reset errno.

       */

      errno = saved_errno;

    }

  }

  return nb;

}

#endif /* HAVE_BSD_STRTOLL */

#endif /* HAVE_STRTOLL */

#ifndef HAVE_STRTOULL

unsigned long long int rep_strtoull(const char *str, char **endptr, int base)

{

#ifdef HAVE_STRTOUQ

  return strtouq(str, endptr, base);

#elif defined(HAVE___STRTOULL)

  return __strtoull(str, endptr, base);

#elif SIZEOF_LONG == SIZEOF_LONG_LONG

  return (unsigned long long int) strtoul(str, endptr, base);

#else

# error "You need a strtoull function"

#endif

}

#else

#ifdef HAVE_BSD_STRTOLL

#undef strtoull

unsigned long long int rep_strtoull(const char *str, char **endptr, int base)

{

  int saved_errno = errno;

  unsigned long long int nb = strtoull(str, endptr, base);

  /* With glibc EINVAL is only returned if base is not ok */

  if (errno == EINVAL) {

    if (base == 0 || (base >1 && base <37)) {

      /* Base was ok so it's because we were not

       * able to make the conversion.

       * Let's reset errno.

       */

      errno = saved_errno;

    }

  }

  return nb;

}

#endif /* HAVE_BSD_STRTOLL */

#endif /* HAVE_STRTOULL */

#ifndef HAVE_SETENV

int rep_setenv(const char *name, const char *value, int overwrite)

{

  char *p;

  size_t l1, l2;

  int ret;

  if (!overwrite && getenv(name)) {

    return 0;

  }

  l1 = strlen(name);

  l2 = strlen(value);

  p = malloc(l1+l2+2);

  if (p == NULL) {

    return -1;

  }

  memcpy(p, name, l1);

  p[l1] = '=';

  memcpy(p+l1+1, value, l2);

  p[l1+l2+1] = 0;

  ret = putenv(p);

  if (ret != 0) {

    free(p);

  }

  return ret;

}

#endif

#ifndef HAVE_UNSETENV

int rep_unsetenv(const char *name)

{

  extern char **environ;

  size_t len = strlen(name);

  size_t i, count;

  if (environ == NULL || getenv(name) == NULL) {

    return 0;

  }

  for (i=0;environ[i];i++) /* noop */ ;

  count=i;

  for (i=0;i<count;) {

    if (strncmp(environ[i], name, len) == 0 && environ[i][len] == '=') {

      /* note: we do _not_ free the old variable here. It is unsafe to

         do so, as the pointer may not have come from malloc */

      memmove(&environ[i], &environ[i+1], (count-i)*sizeof(char *));

      count--;

    } else {

      i++;

    }

  }

  return 0;

}

#endif

#ifndef HAVE_UTIME

int rep_utime(const char *filename, const struct utimbuf *buf)

{

  errno = ENOSYS;

  return -1;

}

#endif

#ifndef HAVE_UTIMES

int rep_utimes(const char *filename, const struct timeval tv[2])

{

  struct utimbuf u;

  u.actime = tv[0].tv_sec;

  if (tv[0].tv_usec > 500000) {

    u.actime += 1;

  }

  u.modtime = tv[1].tv_sec;

  if (tv[1].tv_usec > 500000) {

    u.modtime += 1;

  }

  return utime(filename, &u);

}

#endif

#ifndef HAVE_DUP2

int rep_dup2(int oldfd, int newfd)

{

  errno = ENOSYS;

  return -1;

}

#endif

#ifndef HAVE_CHOWN

/**

chown isn't used much but OS/2 doesn't have it

**/

int rep_chown(const char *fname, uid_t uid, gid_t gid)

{

  errno = ENOSYS;

  return -1;

}

#endif

#ifndef HAVE_LINK

int rep_link(const char *oldpath, const char *newpath)

{

  errno = ENOSYS;

  return -1;

}

#endif

#ifndef HAVE_READLINK

int rep_readlink(const char *path, char *buf, size_t bufsiz)

{

  errno = ENOSYS;

  return -1;

}

#endif

#ifndef HAVE_SYMLINK

int rep_symlink(const char *oldpath, const char *newpath)

{

  errno = ENOSYS;

  return -1;

}

#endif

#ifndef HAVE_LCHOWN

int rep_lchown(const char *fname,uid_t uid,gid_t gid)

{

  errno = ENOSYS;

  return -1;

}

#endif

#ifndef HAVE_REALPATH

char *rep_realpath(const char *path, char *resolved_path)

{

  /* As realpath is not a system call we can't return ENOSYS. */

  errno = EINVAL;

  return NULL;

}

#endif

#ifndef HAVE_MEMMEM

void *rep_memmem(const void *haystack, size_t haystacklen,

     const void *needle, size_t needlelen)

{

  if (needlelen == 0) {

    return discard_const(haystack);

  }

  while (haystacklen >= needlelen) {

    char *p = (char *)memchr(haystack, *(const char *)needle,

           haystacklen-(needlelen-1));

    if (!p) return NULL;

    if (memcmp(p, needle, needlelen) == 0) {

      return p;

    }

    haystack = p+1;

    haystacklen -= (p - (const char *)haystack) + 1;

  }

  return NULL;

}

#endif

#if !defined(HAVE_VDPRINTF) || !defined(HAVE_C99_VSNPRINTF)

int rep_vdprintf(int fd, const char *format, va_list ap)

{

  char *s = NULL;

  int ret;

  vasprintf(&s, format, ap);

  if (s == NULL) {

    errno = ENOMEM;

    return -1;

  }

  ret = write(fd, s, strlen(s));

  free(s);

  return ret;

}

#endif

#if !defined(HAVE_DPRINTF) || !defined(HAVE_C99_VSNPRINTF)

int rep_dprintf(int fd, const char *format, ...)

{

  int ret;

  va_list ap;

  va_start(ap, format);

  ret = vdprintf(fd, format, ap);

  va_end(ap);

  return ret;

}

#endif

#ifndef HAVE_GET_CURRENT_DIR_NAME

char *rep_get_current_dir_name(void)

{

  char buf[PATH_MAX+1];

  char *p;

  p = getcwd(buf, sizeof(buf));

  if (p == NULL) {

    return NULL;

  }

  return strdup(p);

}

#endif

#ifndef HAVE_STRERROR_R

int rep_strerror_r(int errnum, char *buf, size_t buflen)

{

  char *s = strerror(errnum);

  if (strlen(s)+1 > buflen) {

    errno = ERANGE;

    return -1;

  }

  strncpy(buf, s, buflen);

  return 0;

}

#elif (!defined(STRERROR_R_XSI_NOT_GNU))

#undef strerror_r

int rep_strerror_r(int errnum, char *buf, size_t buflen)

{

  char *s = strerror_r(errnum, buf, buflen);

  if (s == NULL) {

    /* Shouldn't happen, should always get a string */

    return EINVAL;

  }

  if (s != buf) {

    strlcpy(buf, s, buflen);

    if (strlen(s) > buflen - 1) {

      return ERANGE;

    }

  }

  return 0;

}

#endif

#ifndef HAVE_CLOCK_GETTIME

int rep_clock_gettime(clockid_t clk_id, struct timespec *tp)

{

  struct timeval tval;

  switch (clk_id) {

    case 0: /* CLOCK_REALTIME :*/

#if defined(HAVE_GETTIMEOFDAY_TZ) || defined(HAVE_GETTIMEOFDAY_TZ_VOID)

      gettimeofday(&tval,NULL);

#else

      gettimeofday(&tval);

#endif

      tp->tv_sec = tval.tv_sec;

      tp->tv_nsec = tval.tv_usec * 1000;

      break;

    default:

      errno = EINVAL;

      return -1;

  }

  return 0;

}

#endif

#ifndef HAVE_MEMALIGN

void *rep_memalign( size_t align, size_t size )

{

#if defined(HAVE_POSIX_MEMALIGN)

  void *p = NULL;

  int ret = posix_memalign( &p, align, size );

  if ( ret == 0 )

    return p;

  return NULL;

#else

  /* On *BSD systems memaligns doesn't exist, but memory will

   * be aligned on allocations of > pagesize. */

#if defined(SYSCONF_SC_PAGESIZE)

  size_t pagesize = (size_t)sysconf(_SC_PAGESIZE);

#elif defined(HAVE_GETPAGESIZE)

  size_t pagesize = (size_t)getpagesize();

#else

  size_t pagesize = (size_t)-1;

#endif

  if (pagesize == (size_t)-1) {

    errno = ENOSYS;

    return NULL;

  }

  if (size < pagesize) {

    size = pagesize;

  }

  return malloc(size);

#endif

}

#endif

#ifndef HAVE_GETPEEREID

int rep_getpeereid(int s, uid_t *uid, gid_t *gid)

{

#if defined(HAVE_PEERCRED)

  struct ucred cred;

  socklen_t cred_len = sizeof(struct ucred);

  int ret;

#undef getsockopt

  ret = getsockopt(s, SOL_SOCKET, SO_PEERCRED, (void *)&cred, &cred_len);

  if (ret != 0) {

    return -1;

  }

  if (cred_len != sizeof(struct ucred)) {

    errno = EINVAL;

    return -1;

  }

  *uid = cred.uid;

  *gid = cred.gid;

  return 0;

#else

  errno = ENOSYS;

  return -1;

#endif

}

#endif

#ifndef HAVE_USLEEP

int rep_usleep(useconds_t sec)

{

  struct timeval tval;

  /*

   * Fake it with select...

   */

  tval.tv_sec = 0;

  tval.tv_usec = usecs/1000;

  select(0,NULL,NULL,NULL,&tval);

  return 0;

}

#endif /* HAVE_USLEEP */

#ifndef HAVE_SETPROCTITLE

void rep_setproctitle(const char *fmt, ...)

{

#if defined(HAVE_PRCTL) && defined(PR_SET_MM_MAP) && defined(__NR_brk)

  /*

   * Implementation based on setproctitle from lcx under LGPL-2.1+

   * https://github.com/lxc/lxc/

   *

   * Using PR_SET_MM_MAP requires CAP_SYS_RESOURCE.

   */

  static char *proctitle = NULL;

  char *tmp_proctitle = NULL;

  char buf[2048] = {0};

  char title[2048] = {0};

  va_list ap;

  char *ptr = NULL;

  FILE *f = NULL;

  size_t title_len;

  int ret = 0;

  struct prctl_mm_map prctl_map = {

    .exe_fd = -1,

  };

  long brk_val = 0;

  /* See `man proc_pid_stat.5` */

  unsigned long start_code = 0;            // 26

  unsigned long end_code = 0;              // 27

  unsigned long start_stack = 0;           // 28

  unsigned long start_data = 0;            // 45

  unsigned long end_data = 0;              // 46

  unsigned long start_brk = 0;             // 47

  unsigned long arg_start = 0;             // 48

  unsigned long arg_end = 0;               // 49

  unsigned long env_start = 0;             // 50

  unsigned long env_end = 0;               // 51

  f = fopen("/proc/self/stat", "r");

  if (f == NULL) {

    return;

  }

  ptr = fgets(buf, sizeof(buf), f);

  fclose(f);

  if (ptr == NULL) {

    return;

  }

  /*

   * Find the last ')' to skip the comm field which can contain spaces and

   * maybe ')'.

   */

  ptr = strrchr(buf, ')');

  if (ptr == NULL || ptr[1] == '\0') {

    return;

  }

  ptr += 2; // Skip ') '

  /* See `man proc_pid_stat.5` */

  ret = sscanf(

    ptr,

    "%*c "        // 3 (state)

    "%*d "        // 4 (ppid)

    "%*d "        // 5 (pgrp)

    "%*d "        // 6 (session)

    "%*d "        // 7 (tty_nr)

    "%*d "        // 8 (tpgid)

    "%*u "        // 9 (flags)

    "%*u "        // 10 (minflt)

    "%*u "        // 11 (cminflt)

    "%*u "        // 12 (majflt)

    "%*u "        // 13 (cmajflt)

    "%*u "        // 14 (utime)

    "%*u "        // 15 (stime)

    "%*d "        // 16 (cutime)

    "%*d "        // 17 (cstime)

    "%*d "        // 18 (priority)

    "%*d "        // 19 (nice)

    "%*d "        // 20 (num_threads)

    "%*d "        // 21 (itrealvalue)

    "%*u "        // 22 (starttime)

    "%*u "        // 23 (vsize)

    "%*d "        // 24 (rss)

    "%*u "        // 25 (rsslim)

    "%lu "        // 26 (start_code)

    "%lu "        // 27 (end_code)

    "%lu "        // 28 (start_stack)

    "%*u "        // 29 (kstkesp)

    "%*u "        // 30 (kstkeip)

    "%*u "        // 31 (signal)

    "%*u "        // 32 (blocked)

    "%*u "        // 33 (sigignore)

    "%*u "        // 34 (sigcatch)

    "%*u "        // 35 (wchan)

    "%*u "        // 36 (nswap)

    "%*u "        // 37 (cnswap)

    "%*d "        // 38 (exit_signal)

    "%*d "        // 39 (processor)

    "%*d "        // 40 (rt_priority)

    "%*u "        // 41 (policy)

    "%*u "        // 42 (delayacct_blkio_ticks)

    "%*u "        // 43 (guest_time)

    "%*d "        // 44 (cguest_time)

    "%lu "        // 45 (start_data)

    "%lu "        // 46 (end_data)

    "%lu "        // 47 (start_brk)

    "%lu "        // 48 (arg_start)

    "%lu "        // 49 (arg_end)

    "%lu "        // 50 (env_start)

    "%lu",        // 51 (env_end)

    &start_code,  // 26

    &end_code,    // 27

    &start_stack, // 28

    &start_data,  // 45

    &end_data,    // 46

    &start_brk,   // 47

    &arg_start,   // 48

    &arg_end,     // 49

    &env_start,   // 50

    &env_end      // 51

  );

  if (ret != 10) {

    return;

  }

  va_start(ap, fmt);

  ret = vsnprintf(title, sizeof(title), fmt, ap);

  va_end(ap);

  if (ret <= 0) {

    return;

  }

  /*

   * Include the null byte here, because in the calculations below

   * we want to have room for it.

   */

  title_len = ret + 1;

  /* This will leak memory */

  tmp_proctitle = realloc(proctitle, title_len);

  if (tmp_proctitle == NULL) {

    return;

  }

  proctitle = tmp_proctitle;

  arg_start = (uint64_t)proctitle;

  arg_end = arg_start + title_len;

  brk_val = syscall(__NR_brk, 0);

  if (brk_val < 0) {

    return;

  }

  prctl_map = (struct prctl_mm_map) {

    .start_code = start_code,

    .end_code = end_code,

    .start_stack = start_stack,

    .start_data = start_data,

    .end_data = end_data,

    .start_brk = start_brk,

    .brk = brk_val,

    .arg_start = arg_start,

    .arg_end = arg_end,

    .env_start = env_start,

    .env_end = env_end,

    .auxv = NULL,

    .auxv_size = 0,

    .exe_fd = -1,

  };

  ret = prctl(PR_SET_MM,

        PR_SET_MM_MAP,

        (long)&prctl_map,

        sizeof(prctl_map),

        0);

  if (ret == 0) {

    strlcpy((char *)arg_start, title, title_len);

  }

#endif /* HAVE_PRCTL */

}

#endif

#ifndef HAVE_SETPROCTITLE_INIT

void rep_setproctitle_init(int argc, char *argv[], char *envp[])

{

}

#endif