/*
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program 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 General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

   xrdp: A Remote Desktop Protocol server.
   Copyright (C) Jay Sorg 2004-2005

   generic operating system calls

   put all the os / arch define in here you want

   if you want pthread calls define USE_PTHREAD in makefile
   if you want openssl calls define USE_OPENSSL in makefile

*/

#if defined(_WIN32)
#include <windows.h>
#include <winsock.h>
#else
#include <unistd.h>
#include <errno.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/time.h>
#include <sys/types.h>
#include <dlfcn.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <signal.h>
#include <fcntl.h>
#endif

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

#if defined(USE_OPENSSL)
#include <openssl/rc4.h>
#include <openssl/md5.h>
#include <openssl/sha.h>
#include <openssl/bn.h>
#endif

#if defined(USE_PTHREAD)
#include <pthread.h>
#endif

/*#define MEMLEAK*/

#if defined(_WIN32)
static CRITICAL_SECTION g_term_mutex;
static int g_term = 0;
#elif defined(USE_PTHREAD)
static pthread_mutex_t g_term_mutex = PTHREAD_MUTEX_INITIALIZER;
static int g_term = 0;
#endif

#if defined(MEMLEAK)
static int g_memsize = 0;
static int g_memid = 0;
static struct list* g_memlist = 0;

/* for memory debugging */
struct mem
{
  int size;
  int id;
};

/* list */
struct list
{
  long* items;
  int count;
  int alloc_size;
  int grow_by;
  int auto_free;
};

/*****************************************************************************/
struct list* list_create(void)
{
  struct list* self;

  self = (struct list*)malloc(sizeof(struct list));
  memset(self, 0, sizeof(struct list));
  self->grow_by = 10;
  self->alloc_size = 10;
  self->items = (long*)malloc(sizeof(long) * 10);
  memset(self->items, 0, sizeof(long) * 10);
  return self;
}

/*****************************************************************************/
void list_delete(struct list* self)
{
  int i;

  if (self == 0)
  {
    return;
  }
  if (self->auto_free)
  {
    for (i = 0; i < self->count; i++)
    {
      free((void*)self->items[i]);
      self->items[i] = 0;
    }
  }
  free(self->items);
  free(self);
}

/*****************************************************************************/
void list_add_item(struct list* self, long item)
{
  long* p;
  int i;

  if (self->count >= self->alloc_size)
  {
    i = self->alloc_size;
    self->alloc_size += self->grow_by;
    p = (long*)malloc(sizeof(long) * self->alloc_size);
    memset(p, 0, sizeof(long) * self->alloc_size);
    memcpy(p, self->items, sizeof(long) * i);
    free(self->items);
    self->items = p;
  }
  self->items[self->count] = item;
  self->count++;
}

/*****************************************************************************/
int list_index_of(struct list* self, long item)
{
  int i;

  for (i = 0; i < self->count; i++)
  {
    if (self->items[i] == item)
    {
      return i;
    }
  }
  return -1;
}

/*****************************************************************************/
void list_remove_item(struct list* self, int index)
{
  int i;

  if (index >= 0 && index < self->count)
  {
    if (self->auto_free)
    {
      free((void*)self->items[index]);
      self->items[index] = 0;
    }
    for (i = index; i < (self->count - 1); i++)
    {
      self->items[i] = self->items[i + 1];
    }
    self->count--;
  }
}

/*****************************************************************************/
long list_get_item(struct list* self, int index)
{
  if (index < 0 || index >= self->count)
  {
    return 0;
  }
  return self->items[index];
}

#endif

/* forward declarations */
void g_printf(char* format, ...);
void g_pipe_sig(int sig_num);

/*****************************************************************************/
int g_init_system(void)
{
#if defined(_WIN32)
  WSADATA w;

  WSAStartup(2, &w);
  InitializeCriticalSection(&g_term_mutex);
#else
  signal(SIGPIPE, g_pipe_sig);
#endif
#if defined(MEMLEAK)
  g_memlist = list_create();
#endif
  return 0;
}

/*****************************************************************************/
int g_exit_system(void)
{
#if defined(_WIN32)
  WSACleanup();
  DeleteCriticalSection(&g_term_mutex);
#endif
#if defined(MEMLEAK)
  int i;
  struct mem* p;

  for (i = 0; i < g_memlist->count; i++)
  {
    p = (struct mem*)list_get_item(g_memlist, i);
    g_printf("leak size %d id %d\n\r", p->size, p->id);
  }
  g_printf("mem %d\n\r", g_memsize);
  list_delete(g_memlist);
  g_memlist = 0;
#endif
  return 0;
}

/*****************************************************************************/
void* g_malloc(int size, int zero)
{
#if defined(MEMLEAK)
  char* rv;
  struct mem* p;

  rv = (char*)malloc(size + sizeof(struct mem));
  if (zero)
  {
    memset(rv, 0, size + sizeof(struct mem));
  }
  g_memsize += size;
  p = (struct mem*)rv;
  p->size = size;
  p->id = g_memid;
  if (g_memlist != 0)
  {
    list_add_item(g_memlist, (long)p);
  }
  g_memid++;
  return rv + sizeof(struct mem);
#else
  char* rv;

  rv = (char*)malloc(size);
  if (zero)
  {
    memset(rv, 0, size);
  }
  return rv;
#endif
}

/*****************************************************************************/
void g_free(void* ptr)
{
#if defined(MEMLEAK)
  struct mem* p;
  int i;

  if (ptr != 0)
  {
    p = (struct mem*)(((char*)ptr) - sizeof(struct mem));
    g_memsize -= p->size;
    i = list_index_of(g_memlist, (long)p);
    if (i >= 0)
    {
      list_remove_item(g_memlist, i);
    }
    free(p);
  }
#else
  if (ptr != 0)
  {
    free(ptr);
  }
#endif
}

/*****************************************************************************/
void g_printf(char* format, ...)
{
  va_list ap;

  va_start(ap, format);
  vfprintf(stdout, format, ap);
  va_end(ap);
}

/*****************************************************************************/
void g_sprintf(char* dest, char* format, ...)
{
  va_list ap;

  va_start(ap, format);
  vsprintf(dest, format, ap);
  va_end(ap);
}

/*****************************************************************************/
/* produce a hex dump */
void g_hexdump(char* p, int len)
{
  unsigned char* line;
  int i;
  int thisline;
  int offset;

  line = (unsigned char*)p;
  offset = 0;
  while (offset < len)
  {
    g_printf("%04x ", offset);
    thisline = len - offset;
    if (thisline > 16)
    {
      thisline = 16;
    }
    for (i = 0; i < thisline; i++)
    {
      g_printf("%02x ", line[i]);
    }
    for (; i < 16; i++)
    {
      g_printf("   ");
    }
    for (i = 0; i < thisline; i++)
    {
      g_printf("%c", (line[i] >= 0x20 && line[i] < 0x7f) ? line[i] : '.');
    }
    g_printf("\n\r");
    offset += thisline;
    line += thisline;
  }
}

/*****************************************************************************/
void g_memset(void* ptr, int val, int size)
{
  memset(ptr, val, size);
}

/*****************************************************************************/
void g_memcpy(void* d_ptr, const void* s_ptr, int size)
{
  memcpy(d_ptr, s_ptr, size);
}

/*****************************************************************************/
int g_getchar(void)
{
  return getchar();
}

/*****************************************************************************/
int g_tcp_set_no_delay(int sck)
{
  int i;

  i = 1;
  setsockopt(sck, IPPROTO_TCP, TCP_NODELAY, (void*)&i, sizeof(i));
  return 0;
}

/*****************************************************************************/
int g_tcp_socket(void)
{
  int rv;
  int i;

  i = 1;
  rv = socket(PF_INET, SOCK_STREAM, 0);
  setsockopt(rv, IPPROTO_TCP, TCP_NODELAY, (void*)&i, sizeof(i));
  return rv;
}

/*****************************************************************************/
int g_tcp_local_socket(void)
{
#if defined(_WIN32)
  return 0;
#else
  return socket(PF_LOCAL, SOCK_STREAM, 0);
#endif
}

/*****************************************************************************/
void g_tcp_close(int sck)
{
  if (sck == 0)
  {
    return;
  }
  shutdown(sck, 2);
#if defined(_WIN32)
  closesocket(sck);
#else
  close(sck);
#endif
}

/*****************************************************************************/
int g_tcp_connect(int sck, char* address, char* port)
{
  struct sockaddr_in s;
  struct hostent* h;

  g_memset(&s, 0, sizeof(struct sockaddr_in));
  s.sin_family = AF_INET;
  s.sin_port = htons(atoi(port));
  s.sin_addr.s_addr = inet_addr(address);
  if (s.sin_addr.s_addr == INADDR_NONE)
  {
    h = gethostbyname(address);
    if (h != 0)
    {
      if (h->h_name != 0)
      {
        if (h->h_addr_list != 0)
        {
          if ((*(h->h_addr_list)) != 0)
          {
            s.sin_addr.s_addr = *((int*)(*(h->h_addr_list)));
          }
        }
      }
    }
  }
  return connect(sck, (struct sockaddr*)&s, sizeof(struct sockaddr_in));
}

/*****************************************************************************/
int g_tcp_set_non_blocking(int sck)
{
  unsigned long i;

#if defined(_WIN32)
  i = 1;
  ioctlsocket(sck, FIONBIO, &i);
#else
  i = fcntl(sck, F_GETFL);
  i = i | O_NONBLOCK;
  fcntl(sck, F_SETFL, i);
#endif
  return 0;
}

/*****************************************************************************/
int g_tcp_bind(int sck, char* port)
{
  struct sockaddr_in s;

  memset(&s, 0, sizeof(struct sockaddr_in));
  s.sin_family = AF_INET;
  s.sin_port = htons(atoi(port));
  s.sin_addr.s_addr = INADDR_ANY;
  return bind(sck, (struct sockaddr*)&s, sizeof(struct sockaddr_in));
}

/*****************************************************************************/
int g_tcp_local_bind(int sck, char* port)
{
#if defined(_WIN32)
  return -1;
#else
  struct sockaddr_un s;

  memset(&s, 0, sizeof(struct sockaddr_un));
  s.sun_family = AF_UNIX;
  strcpy(s.sun_path, port);
  return bind(sck, (struct sockaddr*)&s, sizeof(struct sockaddr_un));
#endif
}

/*****************************************************************************/
int g_tcp_listen(int sck)
{
  return listen(sck, 2);
}

/*****************************************************************************/
int g_tcp_accept(int sck)
{
  struct sockaddr_in s;
#if defined(_WIN32)
  signed int i;
#else
  unsigned int i;
#endif

  i = sizeof(struct sockaddr_in);
  memset(&s, 0, i);
  return accept(sck, (struct sockaddr*)&s, &i);
}

/*****************************************************************************/
void g_sleep(int msecs)
{
#if defined(_WIN32)
  Sleep(msecs);
#else
  usleep(msecs * 1000);
#endif
}

/*****************************************************************************/
int g_tcp_last_error_would_block(int sck)
{
#if defined(_WIN32)
  return WSAGetLastError() == WSAEWOULDBLOCK;
#else
  return errno == EWOULDBLOCK;
#endif
}

/*****************************************************************************/
int g_tcp_recv(int sck, void* ptr, int len, int flags)
{
  return recv(sck, ptr, len, flags);
}

/*****************************************************************************/
int g_tcp_send(int sck, void* ptr, int len, int flags)
{
  return send(sck, ptr, len, flags);
}

/*****************************************************************************/
int g_tcp_select(int sck1, int sck2)
{
  fd_set rfds;
  struct timeval time;
  int max;
  int rv;

  time.tv_sec = 0;
  time.tv_usec = 0;
  FD_ZERO(&rfds);
  if (sck1 > 0)
  {
    FD_SET(((unsigned int)sck1), &rfds);
  }
  if (sck2 > 0)
  {
    FD_SET(((unsigned int)sck2), &rfds);
  }
  max = sck1;
  if (sck2 > max)
  {
    max = sck2;
  }
  rv = select(max + 1, &rfds, 0, 0, &time);
  if (rv > 0)
  {
    rv = 0;
    if (FD_ISSET(((unsigned int)sck1), &rfds))
    {
      rv = rv | 1;
    }
    if (FD_ISSET(((unsigned int)sck2), &rfds))
    {
      rv = rv | 2;
    }
  }
  return rv;
}

/*****************************************************************************/
int g_is_term(void)
{
  int rv;

#if defined(_WIN32)
  EnterCriticalSection(&g_term_mutex);
  rv = g_term;
  LeaveCriticalSection(&g_term_mutex);
#elif defined (USE_PTHREAD)
  pthread_mutex_lock(&g_term_mutex);
  rv = g_term;
  pthread_mutex_unlock(&g_term_mutex);
#else
  rv = 1;
#endif
  return rv;
}

/*****************************************************************************/
void g_set_term(int in_val)
{
#if defined(_WIN32)
  EnterCriticalSection(&g_term_mutex);
  g_term = in_val;
  LeaveCriticalSection(&g_term_mutex);
#elif defined(USE_PTHREAD)
  pthread_mutex_lock(&g_term_mutex);
  g_term = in_val;
  pthread_mutex_unlock(&g_term_mutex);
#endif
}

/*****************************************************************************/
#if defined(_WIN32)
int g_thread_create(unsigned long (__stdcall * start_routine)(void*), void* arg)
{
  DWORD thread;

  return !CreateThread(0, 0, start_routine, arg, 0, &thread);
}
#elif defined(USE_PTHREAD)
int g_thread_create(void* (* start_routine)(void*), void* arg)
{
  pthread_t thread;
  int rv;

  rv = pthread_create(&thread, 0, start_routine, arg);
  pthread_detach(thread);
  return rv;
}
#endif

/*****************************************************************************/
int g_get_threadid(void)
{
#if defined(_WIN32)
  return 0;
#elif defined(USE_PTHREAD)
  return pthread_self();
#else
  return 0;
#endif
}

#if defined(USE_OPENSSL)

/* rc4 stuff */

/*****************************************************************************/
void* g_rc4_info_create(void)
{
  return g_malloc(sizeof(RC4_KEY), 1);;
}

/*****************************************************************************/
void g_rc4_info_delete(void* rc4_info)
{
  g_free(rc4_info);
}

/*****************************************************************************/
void g_rc4_set_key(void* rc4_info, char* key, int len)
{
  RC4_set_key((RC4_KEY*)rc4_info, len, (unsigned char*)key);
}

/*****************************************************************************/
void g_rc4_crypt(void* rc4_info, char* data, int len)
{
  RC4((RC4_KEY*)rc4_info, len, (unsigned char*)data, (unsigned char*)data);
}

/* sha1 stuff */

/*****************************************************************************/
void* g_sha1_info_create(void)
{
  return g_malloc(sizeof(SHA_CTX), 1);
}

/*****************************************************************************/
void g_sha1_info_delete(void* sha1_info)
{
  g_free(sha1_info);
}

/*****************************************************************************/
void g_sha1_clear(void* sha1_info)
{
  SHA1_Init((SHA_CTX*)sha1_info);
}

/*****************************************************************************/
void g_sha1_transform(void* sha1_info, char* data, int len)
{
  SHA1_Update((SHA_CTX*)sha1_info, data, len);
}

/*****************************************************************************/
void g_sha1_complete(void* sha1_info, char* data)
{
  SHA1_Final((unsigned char*)data, (SHA_CTX*)sha1_info);
}

/* md5 stuff */

/*****************************************************************************/
void* g_md5_info_create(void)
{
  return g_malloc(sizeof(MD5_CTX), 1);
}

/*****************************************************************************/
void g_md5_info_delete(void* md5_info)
{
  g_free(md5_info);
}

/*****************************************************************************/
void g_md5_clear(void* md5_info)
{
  MD5_Init((MD5_CTX*)md5_info);
}

/*****************************************************************************/
void g_md5_transform(void* md5_info, char* data, int len)
{
  MD5_Update((MD5_CTX*)md5_info, data, len);
}

/*****************************************************************************/
void g_md5_complete(void* md5_info, char* data)
{
  MD5_Final((unsigned char*)data, (MD5_CTX*)md5_info);
}

/*****************************************************************************/
int g_mod_exp(char* out, char* in, char* mod, char* exp)
{
  BN_CTX* ctx;
  BIGNUM lmod;
  BIGNUM lexp;
  BIGNUM lin;
  BIGNUM lout;
  int rv;

  ctx = BN_CTX_new();
  BN_init(&lmod);
  BN_init(&lexp);
  BN_init(&lin);
  BN_init(&lout);
  BN_bin2bn((unsigned char*)mod, 64, &lmod);
  BN_bin2bn((unsigned char*)exp, 64, &lexp);
  BN_bin2bn((unsigned char*)in, 64, &lin);
  BN_mod_exp(&lout, &lin, &lexp, &lmod, ctx);
  rv = BN_bn2bin(&lout, (unsigned char*)out);
  BN_free(&lin);
  BN_free(&lout);
  BN_free(&lexp);
  BN_free(&lmod);
  BN_CTX_free(ctx);
  return rv;
}

#endif

/*****************************************************************************/
void g_random(char* data, int len)
{
#if defined(_WIN32)
  memset(data, 0x44, len);
#else
  int fd;

  memset(data, 0x44, len);
  fd = open("/dev/urandom", O_RDONLY);
  if (fd == -1)
  {
    fd = open("/dev/random", O_RDONLY);
  }
  if (fd != -1)
  {
    read(fd, data, len);
    close(fd);
  }
#endif
}

/*****************************************************************************/
int g_abs(int i)
{
  return abs(i);
}

/*****************************************************************************/
int g_memcmp(void* s1, void* s2, int len)
{
  return memcmp(s1, s2, len);
}

/*****************************************************************************/
int g_file_open(char* file_name)
{
#if defined(_WIN32)
  return (int)CreateFile(file_name, GENERIC_READ | GENERIC_WRITE,
                         FILE_SHARE_READ | FILE_SHARE_WRITE,
                         0, OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, 0);
#else
  return open(file_name, O_RDWR | O_CREAT);
#endif
}

/*****************************************************************************/
int g_file_close(int fd)
{
#if defined(_WIN32)
  CloseHandle((HANDLE)fd);
#else
  close(fd);
#endif
  return 0;
}

/*****************************************************************************/
/* read from file*/
int g_file_read(int fd, char* ptr, int len)
{
#if defined(_WIN32)
  if (ReadFile((HANDLE)fd, (LPVOID)ptr, (DWORD)len, (LPDWORD)&len, 0))
  {
    return len;
  }
  else
  {
    return -1;
  }
#else
  return read(fd, ptr, len);
#endif
}

/*****************************************************************************/
/* write to file */
int g_file_write(int fd, char* ptr, int len)
{
#if defined(_WIN32)
  if (WriteFile((HANDLE)fd, (LPVOID)ptr, (DWORD)len, (LPDWORD)&len, 0))
  {
    return len;
  }
  else
  {
    return -1;
  }
#else
  return write(fd, ptr, len);
#endif
}

/*****************************************************************************/
/* move file pointer */
int g_file_seek(int fd, int offset)
{
#if defined(_WIN32)
  return SetFilePointer((HANDLE)fd, offset, 0, FILE_BEGIN);
#else
  return lseek(fd, offset, SEEK_SET);
#endif
}

/*****************************************************************************/
/* do a write lock on a file */
/* return boolean */
int g_file_lock(int fd, int start, int len)
{
#if defined(_WIN32)
  return LockFile((HANDLE)fd, start, 0, len, 0);
#else
  struct flock lock;

  lock.l_type = F_WRLCK;
  lock.l_whence = SEEK_SET;
  lock.l_start = start;
  lock.l_len = len;
  if (fcntl(fd, F_SETLK, &lock) == -1)
  {
    return 0;
  }
  return 1;
#endif
}

/*****************************************************************************/
int g_strlen(char* text)
{
  if (text == 0)
  {
    return 0;
  }
  return strlen(text);
}

/*****************************************************************************/
char* g_strcpy(char* dest, char* src)
{
  if (src == 0 && dest != 0)
  {
    dest[0] = 0;
    return dest;
  }
  if (dest == 0 || src == 0)
  {
    return 0;
  }
  return strcpy(dest, src);
}

/*****************************************************************************/
char* g_strncpy(char* dest, char* src, int len)
{
  char* rv;

  if (src == 0 && dest != 0)
  {
    dest[0] = 0;
    return dest;
  }
  if (dest == 0 || src == 0)
  {
    return 0;
  }
  rv = strncpy(dest, src, len);
  dest[len] = 0;
  return rv;
}

/*****************************************************************************/
char* g_strcat(char* dest, char* src)
{
  if (dest == 0 || src == 0)
  {
    return dest;
  }
  return strcat(dest, src);
}

/*****************************************************************************/
char* g_strdup(char* in)
{
  int len;
  char* p;

  if (in == 0)
  {
    return 0;
  }
  len = g_strlen(in);
  p = (char*)g_malloc(len + 1, 0);
  g_strcpy(p, in);
  return p;
}

/*****************************************************************************/
int g_strcmp(char* c1, char* c2)
{
  return strcmp(c1, c2);
}

/*****************************************************************************/
int g_strncmp(char* c1, char* c2, int len)
{
  return strncmp(c1, c2, len);
}

/*****************************************************************************/
long g_load_library(char* in)
{
#if defined(_WIN32)
  return 0;
#else
  return (long)dlopen(in, RTLD_LOCAL | RTLD_LAZY);
#endif
}

/*****************************************************************************/
int g_free_library(long lib)
{
  if (lib == 0)
  {
    return 0;
  }
#if defined(_WIN32)
  return 0;
#else
  return dlclose((void*)lib);
#endif
}

/*****************************************************************************/
/* returns NULL if not found */
void* g_get_proc_address(long lib, char* name)
{
  if (lib == 0)
  {
    return 0;
  }
#if defined(_WIN32)
  return 0;
#else
  return dlsym((void*)lib, name);
#endif
}

/*****************************************************************************/
int g_system(char* aexec)
{
#if defined(_WIN32)
  return 0;
#else
  return system(aexec);
#endif
}

/*****************************************************************************/
void g_signal(int sig_num, void (*func)(int))
{
#if defined(_WIN32)
#else
  signal(sig_num, func);
#endif
}

/*****************************************************************************/
void g_pipe_sig(int sig_num)
{
  /* do nothing */
  g_printf("got SIGPIPE(%d)\n\r", sig_num);
}