Urlader/urlader.c

#ifndef URLADER
# define URLADER "urlader"
#endif
#define URLADER_VERSION "1.0" // a decimal number, not a version string

#define MAX_ARGC 32
#define MAX_ARGS 256

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <time.h>
#include <fcntl.h>

#include "liblzf/lzf_d.c"

#define TAIL_MAGIC "SCHMORPPACK0"

#ifdef _WIN32

  #include <windows.h>
  //#include <winbase.h>
  #include <shlobj.h>
  #include <shlwapi.h>
  #include <wininet.h>

  static DWORD dword;

  #define u_handle HANDLE
  #define u_invalid_handle 0
  #define u_valid(handle) (!!handle)

  #define u_setenv(name,value) SetEnvironmentVariable (name, value)
  #define u_mkdir(path) !CreateDirectory (path, NULL)
  #define u_chdir(path) !SetCurrentDirectory (path)
  #define u_rename(fr,to) !MoveFile (fr, to)
  #define u_open(path) CreateFile (path, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL | FILE_FLAG_SEQUENTIAL_SCAN, NULL)
  #define u_creat(path,exec) CreateFile (path, GENERIC_WRITE, FILE_SHARE_WRITE, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL | FILE_FLAG_SEQUENTIAL_SCAN, NULL)
  #define u_creat(path,exec) CreateFile (path, GENERIC_WRITE, FILE_SHARE_WRITE, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL | FILE_FLAG_SEQUENTIAL_SCAN, NULL)
  #define u_close(handle) CloseHandle (handle)
  #define u_append(path,add) PathAppend (path, add)
  #define u_write(handle,data,len) (WriteFile (handle, data, len, &dword, 0) ? dword : -1)

  #define u_fsync(handle) FlushFileBuffers (handle)
  #define u_sync()

  #define u_lockfile(path) CreateFile (path, GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL)
  #define u_cloexec(handle)

#else

  #define _GNU_SOURCE 1
  #define _BSD_SOURCE 1
  // the above increases our chances of getting MAP_ANONYMOUS

  #include <sys/mman.h>
  #include <sys/types.h>
  #include <sys/stat.h>
  #include <unistd.h>
  #include <pwd.h>

  #if defined (MAP_ANON) && !defined (MAP_ANONYMOUS)
    #define MAP_ANONYMOUS MAP_ANON
  #endif

  #ifdef PATH_MAX
    #define MAX_PATH (PATH_MAX < 4096 ? 4096 : PATH_MAX)
  #else
    #define MAX_PATH 4096
  #endif

  #define u_handle int
  #define u_invalid_handle -1
  #define u_valid(fd) ((fd) >= 0)

  #define u_setenv(name,value) setenv (name, value, 1)
  #define u_mkdir(path) mkdir (path, 0777)
  #define u_chdir(path) chdir (path)
  #define u_rename(fr,to) rename (fr, to)
  #define u_open(path) open (path, O_RDONLY)
  #define u_creat(path,exec) open (path, O_WRONLY | O_CREAT | O_TRUNC, (exec) ? 0777 : 0666)
  #define u_close(handle) close (handle)
  #define u_append(path,add) strcat (strcat (path, "/"), add)
  #define u_write(handle,data,len) write (handle, data, len)

  // on a mostly idle system, a sync at the end is certainly faster, hope for the best
  #define u_fsync(handle)
  #define u_sync() sync ()

  #define u_lockfile(path) open (path, O_RDWR | O_CREAT, 0666)
  #define u_cloexec(handle) fcntl (handle, F_SETFD, FD_CLOEXEC)

#endif

#define u_16(ptr) (((ptr)[0] << 8) | (ptr)[1])
#define u_32(ptr) (((ptr)[0] << 24) | ((ptr)[1] << 16) | ((ptr)[2] << 8) | (ptr)[3])

/* some simple? dynamic memory management for paths might save ltos of ram */
static u_handle pack_handle;
static u_handle lock_handle;
static char tmppath[MAX_PATH];
static char currdir[MAX_PATH];
static char datadir[MAX_PATH];  // %AppData%/urlader
static char exe_dir[MAX_PATH];  // %AppData%/urlader/EXE_ID
static char execdir[MAX_PATH];  // %AppData%/urlader/EXE_ID/EXE_VER
static char exe_id[MAX_PATH];
static char exe_ver[MAX_PATH];

static int exe_argc;
static const char *exe_argv[MAX_ARGC];
static char exe_args[MAX_ARGS]; /* actual arguments strings copied here */
static unsigned int exe_argo;

static void
fatal (const char *msg)
{
#ifdef _WIN32
  MessageBox (0, msg, URLADER, 0);
#else
  write (2, URLADER ": ", sizeof (URLADER ": ") - 1);
  write (2, msg, strlen (msg));
  write (2, "\n", 1);
#endif

  _exit (1);
}

static void *
u_malloc (unsigned int size)
{
  void *addr;

#ifdef _WIN32
  HANDLE handle = CreateFileMapping (0, 0, PAGE_READWRITE, 0, size, NULL);

  if (!handle)
    return 0;

  addr = MapViewOfFile (handle, FILE_MAP_WRITE, 0, 0, size);

  CloseHandle (handle);
#elif defined (MAP_ANONYMOUS)
  addr = mmap (0, size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);

  if (addr == (void *)-1)
    addr = 0;
#else
  addr = malloc (size);
#endif

  return addr;
}

static void
u_free (void *addr, unsigned int size)
{
#ifdef _WIN32
  UnmapViewOfFile (addr);
#elif defined (MAP_ANONYMOUS)
  munmap (addr, size);
#else
  free (addr);
#endif
}

static void *
u_mmap (u_handle h, unsigned int size)
{
  void *addr;

#ifdef _WIN32
  HANDLE handle = CreateFileMapping (h, 0, PAGE_READONLY, 0, size, NULL);

  if (!handle)
    return 0;

  addr = MapViewOfFile (handle, FILE_MAP_READ, 0, 0, size);

  CloseHandle (handle);
#else
  addr = mmap (0, size, PROT_READ, MAP_SHARED, h, 0);

  if (addr == (void *)-1)
    addr = 0;
#endif

  return addr;
}

static void
u_munmap (void *addr, unsigned int len)
{
#ifdef _WIN32
  UnmapViewOfFile (addr);
#else
  munmap (addr, len);
#endif
}

static void
tmpdir (const char *dir)
{
  static int cnt;

  for (;;)
    {
//      #ifdef _WIN32
//        sprintf (tmppath, "%s/%x_%x.tmp", dir, (unsigned int)GetCurrentProcessId (), ++cnt);
//      #else
        sprintf (tmppath, "%s/t-%x_%x.tmp", dir, (unsigned int)getpid ()             , ++cnt);
//      #endif

      if (!u_mkdir (tmppath))
        return;
    }
}

static u_handle
u_lock (const char *path, int excl, int dowait)
{
  u_handle h;

  h = u_lockfile (path);
  if (!u_valid (h))
    return h;

  u_cloexec (h);

  for (;;)
    {
      int success;

      // acquire the lock
#ifdef _WIN32
      OVERLAPPED ov = { 0 };

      success = LockFileEx (h,
                            (excl ? LOCKFILE_EXCLUSIVE_LOCK : 0)
                            | (dowait ? 0 : LOCKFILE_FAIL_IMMEDIATELY),
                            0,
                            1, 0,
                            &ov);
#else
      struct flock lck = { 0 };

      lck.l_type   = excl ? F_WRLCK : F_RDLCK;
      lck.l_whence = SEEK_SET;
      lck.l_len    = 1;

      success = !fcntl (h, dowait ? F_SETLKW : F_SETLK, &lck);
#endif

      if (!success)
        break;

      // we have the lock, now verify that the lockfile still exists

#ifdef _WIN32
      // apparently, we have to open the file to get its info :(
      BY_HANDLE_FILE_INFORMATION s1, s2;
      u_handle h2 = u_lockfile (path);
      if (!u_valid (h))
        break;

      success = GetFileInformationByHandle (h, &s1)
                && GetFileInformationByHandle (h2, &s2);

      u_close (h2);

      if (!success)
        break;

      success = s1.dwVolumeSerialNumber == s2.dwVolumeSerialNumber
             && s1.nFileIndexHigh       == s2.nFileIndexHigh
             && s1.nFileIndexLow        == s2.nFileIndexLow;
#else
      struct stat s1, s2;

      if (fstat (h, &s1) || stat (path, &s2))
        break;

      success = s1.st_dev == s2.st_dev
             && s1.st_ino == s2.st_ino;
#endif

      if (success)
        return h; // lock successfully acquired

      // files differ, close and retry - should be very rare
      u_close (h);
    }

  // failure
  u_close (h);
  return u_invalid_handle;
}

static void
systemv (const char *const argv[])
{
#ifdef _WIN32
  _spawnv (P_WAIT, argv [0], argv);
#else
  pid_t pid = fork ();

  if (pid < 0)
    fatal ("fork failure");

  if (!pid)
    {
      execv (argv [0], (void *)argv);
      _exit (124);
    }

  int status;
  waitpid (pid, &status, 0);
#endif
}

static void
deltree (const char *path)
{
  #ifdef _WIN32
    char buf[MAX_PATH * 2 + 64];
    const char *argv[] = { getenv ("COMSPEC"), "/c", "rd", "/s", "/q", buf, 0 };
    sprintf (buf, "\"%s\"", path);
  #else
    const char *argv[] = { "/bin/rm", "-rf", path, 0 };
  #endif
  systemv (argv);
}

enum
{
  T_NULL, // 5
  T_META, // 1 : exe_id, exe_ver
  T_ENV,  // 2 : name, value
  T_ARG,  // 3 : arg
  T_DIR,  // 4+: path
  T_FILE, // 4+: path, data
  T_NUM
};

enum
{
  F_EXEC = 1,
  F_LZF  = 2,
  F_NULL = 0
};

struct hdr
{
  unsigned char type;
  unsigned char flags;
  unsigned char namelen[2];
  unsigned char datalen[4];
};

struct tail {
  unsigned char max_filesize[4];
  unsigned char size[4];
  char magic[12];
};

static char *pack_base, *pack_end;
static struct hdr *pack_cur;
static char *scratch;
static unsigned int scratch_size;

#define PACK_NAME ((char *)(pack_cur + 1))
#define PACK_DATA (PACK_NAME + u_16 (pack_cur->namelen) + 1)
#define PACK_VALID pack_cur->type

static void
pack_next (void)
{
  unsigned int d = u_32 (pack_cur->datalen);

  pack_cur = (struct hdr *)(PACK_DATA + d);
}

static void
pack_unmap (void)
{
  if (pack_base)
    {
      u_munmap (pack_base, pack_end - pack_base);
      pack_base = 0;
    }

  if (scratch)
    {
      u_free (scratch, scratch_size);
      scratch = 0;
    }
}

static int
pack_map (void)
{
  char *addr;
  unsigned int size;

#ifdef _WIN32
  BY_HANDLE_FILE_INFORMATION fi;

  if (!GetFileInformationByHandle (pack_handle, &fi))
    return 0;

  size = fi.nFileSizeLow;
#else
  size = lseek (pack_handle, 0, SEEK_END);
#endif

  addr = u_mmap (pack_handle, size);
  if (!addr)
    return 0;

  pack_unmap ();

  pack_base = addr;
  pack_end  = pack_base + size;

  struct tail *tail;

  tail = (void *)(pack_end - sizeof (*tail));

  if (memcmp (tail->magic, TAIL_MAGIC, sizeof (TAIL_MAGIC) - 1))
    return 0;

  pack_cur = (struct hdr *)(pack_end - u_32 (tail->size));

  scratch = u_malloc (scratch_size = u_32 (tail->max_filesize));
  if (!scratch)
    return 0;

  return 1;
}

static void
exe_info (void)
{
  if (!pack_map ())
    fatal ("unable to locate packfile in executable - executable corrupted?");

  if (pack_cur->type != T_META)
    fatal ("unable to locate executable metadata - executable corrupted?");

  strcpy (exe_id, PACK_NAME);
}

static void
load (void)
{
  u_mkdir (datadir);

  strcpy (exe_dir, datadir);
  u_append (exe_dir, exe_id);
  u_mkdir (exe_dir);

  if (u_chdir (exe_dir))
    fatal ("unable to change to application data directory");

  u_handle h = u_open ("override");
  if (u_valid (h))
    {
      u_handle oh = pack_handle;

      pack_handle = h;
      if (!pack_map ())
        {
          pack_handle = oh;
          oh = h;
        }

      u_close (oh);
    }

  if (pack_cur->type != T_META)
    fatal ("unable to locate override metadata");

  strcpy (exe_ver, PACK_DATA);
  pack_next ();

  for (;;)
    {
      if (pack_cur->type == T_ENV)
        u_setenv (PACK_NAME, PACK_DATA);
      else if (pack_cur->type == T_ARG)
        {
          int len = u_16 (pack_cur->namelen) + 1;
          exe_argv [exe_argc++] = exe_args + exe_argo;
          memcpy (exe_args + exe_argo, PACK_NAME, len);
          exe_argo += len;
        }
      else
        break;

      pack_next ();
    }
 
done_env_arg:
  strcpy (execdir, exe_dir);
  u_append (execdir, "i-");
  strcat (execdir, exe_ver);

  strcat (strcpy (tmppath, execdir), ".lck");
  lock_handle = u_lock (tmppath, 0, 1);
  if (!lock_handle)
    fatal ("unable to lock application instance");

  if (access (execdir, F_OK))
    {
      // does not exist yet, so unpack and move
      tmpdir (exe_dir);

      if (u_chdir (tmppath))
        fatal ("unable to change to new instance directory");

      for (;;)
        {
          switch (pack_cur->type)
            {
              case T_DIR:
                u_mkdir (PACK_NAME);
                break;

              case T_FILE:
                {
                  u_handle h = u_creat (PACK_NAME, pack_cur->flags & F_EXEC);
                  unsigned int dlen, len = u_32 (pack_cur->datalen);
                  char *data = PACK_DATA;

                  if (pack_cur->flags & F_LZF)
                    if (dlen = lzf_decompress (data, len, scratch, scratch_size))
                      {
                        data = scratch;
                        len  = dlen;
                      }
                    else
                      fatal ("unable to uncompress file data - pack corrupted?");

                  if (!u_valid (h))
                    fatal ("unable to unpack file from packfile - disk full?");

                  if (u_write (h, data, len) != len)
                    fatal ("unable to unpack file from packfile - disk full?");

                  u_fsync (h);
                  u_close (h);
                }
                break;

              case T_NULL:
                goto done;
            }

          pack_next ();
        }

done:
      if (u_chdir (datadir))
        fatal ("unable to change to data directory");

      u_sync ();

      if (u_rename (tmppath, execdir))
        deltree (tmppath); // if move fails, delete new, assume other process created it independently
    }

  pack_unmap ();
  u_close (pack_handle);

  if (u_chdir (execdir))
    fatal ("unable to change to application instance directory");

  u_setenv ("URLADER_VERSION", URLADER_VERSION);
  u_setenv ("URLADER_DATADIR", datadir);
  u_setenv ("URLADER_EXECDIR", execdir);
  u_setenv ("URLADER_EXE_ID" , exe_id);
  u_setenv ("URLADER_EXE_DIR", exe_dir);
  u_setenv ("URLADER_EXE_VER", exe_ver);

#if 0
  // yes, this is overkill
  u_setenv ("SHLIB_PATH"        , execdir); // hpux
  u_setenv ("LIBPATH"           , execdir); // aix
  u_setenv ("LD_LIBRARY_PATH"   , execdir); // most elf systems
  u_setenv ("LD_LIBRARY_PATH_32", execdir); // solaris
  u_setenv ("LD_LIBRARY_PATH_64", execdir); // solaris
  u_setenv ("LD_LIBRARYN32_PATH", execdir); // irix
  u_setenv ("LD_LIBRARY64_PATH" , execdir); // irix
  u_setenv ("DYLD_LIBRARY_PATH" , execdir); // os sucks from apple
#endif
}

static void
execute (void)
{
  exe_argv [exe_argc] = 0;
  systemv (exe_argv);
}

#ifdef _WIN32

int APIENTRY
WinMain (HINSTANCE hI, HINSTANCE hP, LPSTR argv, int command_show)
{
  if (!GetModuleFileName (hI, tmppath, sizeof (tmppath)))
    fatal ("unable to find executable pack");

  pack_handle = u_open (tmppath);
  if (!u_valid (pack_handle))
    fatal ("unable to open executable pack");

  exe_info ();

  if (!GetCurrentDirectory (sizeof (currdir), currdir))
    strcpy (currdir, ".");

  if (SHGetFolderPath (0, CSIDL_APPDATA | CSIDL_FLAG_CREATE, NULL, SHGFP_TYPE_CURRENT, datadir) != S_OK)
    fatal ("unable to find application data directory");

  u_mkdir (datadir);
  u_append (datadir, URLADER);

  load ();
  execute ();

  return 0;
}

#else

int
main (int argc, char *argv[])
{
  char *home = getenv ("HOME");

  pack_handle = u_open (argv [0]);
  if (!u_valid (pack_handle))
    fatal ("unable to open executable pack");

  exe_info ();

  if (!home)
    {
      struct passwd *pw;

      if ((pw = getpwuid (getuid ())))
        home = pw->pw_dir;
      else
        home = "/tmp";
    }

  if (!getcwd (currdir, sizeof (currdir)))
    strcpy (currdir, ".");

  u_mkdir (home);
  //strcat (strcat (strcpy (datadir, home), "/."), URLADER);
  sprintf (datadir, "%s/.%s", home, URLADER);
  u_mkdir (datadir);

#if 0
  if (gethostname (tmppath, sizeof (tmppath)))
    strcpy (tmppath, "default");

  u_append (datadir, tmppath);
#endif

  load ();
  execute ();

  return 0;
}

#endif

Revision:	1.7
Committed:	Fri Dec 30 14:51:45 2011 UTC (12 years, 4 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.6:	+74 -39 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	#ifndef URLADER
2			# define URLADER "urlader"
3			#endif
4	root	1.5	#define URLADER_VERSION "1.0" // a decimal number, not a version string
5	root	1.1
6	root	1.6	#define MAX_ARGC 32
7			#define MAX_ARGS 256
8
9	root	1.1	#include <stdio.h>
10			#include <stdlib.h>
11			#include <unistd.h>
12			#include <errno.h>
13			#include <string.h>
14			#include <time.h>
15			#include <fcntl.h>
16
17	root	1.2	#include "liblzf/lzf_d.c"
18	root	1.1
19			#define TAIL_MAGIC "SCHMORPPACK0"
20
21			#ifdef _WIN32
22
23	root	1.6	#include <windows.h>
24			//#include <winbase.h>
25			#include <shlobj.h>
26			#include <shlwapi.h>
27			#include <wininet.h>
28
29			static DWORD dword;
30
31			#define u_handle HANDLE
32			#define u_invalid_handle 0
33			#define u_valid(handle) (!!handle)
34
35			#define u_setenv(name,value) SetEnvironmentVariable (name, value)
36			#define u_mkdir(path) !CreateDirectory (path, NULL)
37			#define u_chdir(path) !SetCurrentDirectory (path)
38			#define u_rename(fr,to) !MoveFile (fr, to)
39			#define u_open(path) CreateFile (path, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL \| FILE_FLAG_SEQUENTIAL_SCAN, NULL)
40			#define u_creat(path,exec) CreateFile (path, GENERIC_WRITE, FILE_SHARE_WRITE, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL \| FILE_FLAG_SEQUENTIAL_SCAN, NULL)
41			#define u_creat(path,exec) CreateFile (path, GENERIC_WRITE, FILE_SHARE_WRITE, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL \| FILE_FLAG_SEQUENTIAL_SCAN, NULL)
42			#define u_close(handle) CloseHandle (handle)
43			#define u_append(path,add) PathAppend (path, add)
44			#define u_write(handle,data,len) (WriteFile (handle, data, len, &dword, 0) ? dword : -1)
45
46			#define u_fsync(handle) FlushFileBuffers (handle)
47			#define u_sync()
48
49			#define u_lockfile(path) CreateFile (path, GENERIC_READ \| GENERIC_WRITE, FILE_SHARE_READ \| FILE_SHARE_WRITE, NULL, OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL)
50			#define u_cloexec(handle)
51
52			#else
53
54			#define _GNU_SOURCE 1
55			#define _BSD_SOURCE 1
56			// the above increases our chances of getting MAP_ANONYMOUS
57
58			#include <sys/mman.h>
59			#include <sys/types.h>
60	root	1.7	#include <sys/stat.h>
61			#include <unistd.h>
62	root	1.6	#include <pwd.h>
63	root	1.4
64	root	1.6	#if defined (MAP_ANON) && !defined (MAP_ANONYMOUS)
65			#define MAP_ANONYMOUS MAP_ANON
66			#endif
67	root	1.1
68	root	1.6	#ifdef PATH_MAX
69			#define MAX_PATH (PATH_MAX < 4096 ? 4096 : PATH_MAX)
70			#else
71			#define MAX_PATH 4096
72			#endif
73	root	1.1
74	root	1.6	#define u_handle int
75			#define u_invalid_handle -1
76			#define u_valid(fd) ((fd) >= 0)
77
78			#define u_setenv(name,value) setenv (name, value, 1)
79			#define u_mkdir(path) mkdir (path, 0777)
80			#define u_chdir(path) chdir (path)
81			#define u_rename(fr,to) rename (fr, to)
82			#define u_open(path) open (path, O_RDONLY)
83			#define u_creat(path,exec) open (path, O_WRONLY \| O_CREAT \| O_TRUNC, (exec) ? 0777 : 0666)
84			#define u_close(handle) close (handle)
85			#define u_append(path,add) strcat (strcat (path, "/"), add)
86			#define u_write(handle,data,len) write (handle, data, len)
87
88			// on a mostly idle system, a sync at the end is certainly faster, hope for the best
89			#define u_fsync(handle)
90			#define u_sync() sync ()
91
92			#define u_lockfile(path) open (path, O_RDWR \| O_CREAT, 0666)
93			#define u_cloexec(handle) fcntl (handle, F_SETFD, FD_CLOEXEC)
94	root	1.1
95			#endif
96
97			#define u_16(ptr) (((ptr)[0] << 8) \| (ptr)[1])
98			#define u_32(ptr) (((ptr)[0] << 24) \| ((ptr)[1] << 16) \| ((ptr)[2] << 8) \| (ptr)[3])
99
100	root	1.6	/* some simple? dynamic memory management for paths might save ltos of ram */
101	root	1.1	static u_handle pack_handle;
102	root	1.6	static u_handle lock_handle;
103	root	1.1	static char tmppath[MAX_PATH];
104			static char currdir[MAX_PATH];
105			static char datadir[MAX_PATH]; // %AppData%/urlader
106			static char exe_dir[MAX_PATH]; // %AppData%/urlader/EXE_ID
107			static char execdir[MAX_PATH]; // %AppData%/urlader/EXE_ID/EXE_VER
108			static char exe_id[MAX_PATH];
109			static char exe_ver[MAX_PATH];
110
111			static int exe_argc;
112	root	1.6	static const char *exe_argv[MAX_ARGC];
113			static char exe_args[MAX_ARGS]; /* actual arguments strings copied here */
114			static unsigned int exe_argo;
115	root	1.1
116			static void
117			fatal (const char *msg)
118			{
119			#ifdef _WIN32
120			MessageBox (0, msg, URLADER, 0);
121			#else
122	root	1.6	write (2, URLADER ": ", sizeof (URLADER ": ") - 1);
123			write (2, msg, strlen (msg));
124			write (2, "\n", 1);
125	root	1.1	#endif
126
127			_exit (1);
128			}
129
130	root	1.6	static void *
131			u_malloc (unsigned int size)
132			{
133			void *addr;
134
135			#ifdef _WIN32
136			HANDLE handle = CreateFileMapping (0, 0, PAGE_READWRITE, 0, size, NULL);
137
138			if (!handle)
139			return 0;
140
141			addr = MapViewOfFile (handle, FILE_MAP_WRITE, 0, 0, size);
142
143			CloseHandle (handle);
144			#elif defined (MAP_ANONYMOUS)
145			addr = mmap (0, size, PROT_READ \| PROT_WRITE, MAP_PRIVATE \| MAP_ANON, -1, 0);
146
147			if (addr == (void *)-1)
148			addr = 0;
149			#else
150			addr = malloc (size);
151			#endif
152
153			return addr;
154			}
155
156			static void
157			u_free (void *addr, unsigned int size)
158			{
159			#ifdef _WIN32
160			UnmapViewOfFile (addr);
161			#elif defined (MAP_ANONYMOUS)
162			munmap (addr, size);
163			#else
164			free (addr);
165			#endif
166			}
167
168			static void *
169			u_mmap (u_handle h, unsigned int size)
170			{
171			void *addr;
172
173			#ifdef _WIN32
174			HANDLE handle = CreateFileMapping (h, 0, PAGE_READONLY, 0, size, NULL);
175
176			if (!handle)
177			return 0;
178
179			addr = MapViewOfFile (handle, FILE_MAP_READ, 0, 0, size);
180
181			CloseHandle (handle);
182			#else
183			addr = mmap (0, size, PROT_READ, MAP_SHARED, h, 0);
184
185			if (addr == (void *)-1)
186			addr = 0;
187			#endif
188
189			return addr;
190			}
191
192			static void
193			u_munmap (void *addr, unsigned int len)
194			{
195			#ifdef _WIN32
196			UnmapViewOfFile (addr);
197			#else
198			munmap (addr, len);
199			#endif
200			}
201
202	root	1.1	static void
203			tmpdir (const char *dir)
204			{
205			static int cnt;
206
207			for (;;)
208			{
209			// #ifdef _WIN32
210			// sprintf (tmppath, "%s/%x_%x.tmp", dir, (unsigned int)GetCurrentProcessId (), ++cnt);
211			// #else
212			sprintf (tmppath, "%s/t-%x_%x.tmp", dir, (unsigned int)getpid () , ++cnt);
213			// #endif
214
215			if (!u_mkdir (tmppath))
216			return;
217			}
218			}
219
220	root	1.7	static u_handle
221			u_lock (const char *path, int excl, int dowait)
222	root	1.6	{
223	root	1.7	u_handle h;
224
225			h = u_lockfile (path);
226			if (!u_valid (h))
227			return h;
228
229			u_cloexec (h);
230
231			for (;;)
232			{
233			int success;
234	root	1.6
235	root	1.7	// acquire the lock
236	root	1.6	#ifdef _WIN32
237			OVERLAPPED ov = { 0 };
238
239	root	1.7	success = LockFileEx (h,
240			(excl ? LOCKFILE_EXCLUSIVE_LOCK : 0)
241			\| (dowait ? 0 : LOCKFILE_FAIL_IMMEDIATELY),
242			0,
243			1, 0,
244			&ov);
245			#else
246			struct flock lck = { 0 };
247
248			lck.l_type = excl ? F_WRLCK : F_RDLCK;
249			lck.l_whence = SEEK_SET;
250			lck.l_len = 1;
251
252			success = !fcntl (h, dowait ? F_SETLKW : F_SETLK, &lck);
253			#endif
254
255			if (!success)
256			break;
257
258			// we have the lock, now verify that the lockfile still exists
259
260			#ifdef _WIN32
261			// apparently, we have to open the file to get its info :(
262			BY_HANDLE_FILE_INFORMATION s1, s2;
263			u_handle h2 = u_lockfile (path);
264			if (!u_valid (h))
265			break;
266
267			success = GetFileInformationByHandle (h, &s1)
268			&& GetFileInformationByHandle (h2, &s2);
269
270			u_close (h2);
271
272			if (!success)
273			break;
274
275			success = s1.dwVolumeSerialNumber == s2.dwVolumeSerialNumber
276			&& s1.nFileIndexHigh == s2.nFileIndexHigh
277			&& s1.nFileIndexLow == s2.nFileIndexLow;
278	root	1.6	#else
279	root	1.7	struct stat s1, s2;
280	root	1.6
281	root	1.7	if (fstat (h, &s1) \|\| stat (path, &s2))
282			break;
283
284			success = s1.st_dev == s2.st_dev
285			&& s1.st_ino == s2.st_ino;
286	root	1.6	#endif
287	root	1.7
288			if (success)
289			return h; // lock successfully acquired
290
291			// files differ, close and retry - should be very rare
292			u_close (h);
293			}
294
295			// failure
296			u_close (h);
297			return u_invalid_handle;
298	root	1.6	}
299
300	root	1.1	static void
301	root	1.6	systemv (const char *const argv[])
302	root	1.1	{
303			#ifdef _WIN32
304			_spawnv (P_WAIT, argv [0], argv);
305			#else
306	root	1.6	pid_t pid = fork ();
307	root	1.1
308			if (pid < 0)
309			fatal ("fork failure");
310
311			if (!pid)
312			{
313			execv (argv [0], (void *)argv);
314			_exit (124);
315			}
316
317			int status;
318			waitpid (pid, &status, 0);
319			#endif
320			}
321
322			static void
323			deltree (const char *path)
324			{
325			#ifdef _WIN32
326			char buf[MAX_PATH * 2 + 64];
327			const char *argv[] = { getenv ("COMSPEC"), "/c", "rd", "/s", "/q", buf, 0 };
328			sprintf (buf, "\"%s\"", path);
329			#else
330			const char *argv[] = { "/bin/rm", "-rf", path, 0 };
331			#endif
332	root	1.6	systemv (argv);
333	root	1.1	}
334
335			enum
336			{
337			T_NULL, // 5
338			T_META, // 1 : exe_id, exe_ver
339	root	1.4	T_ENV, // 2 : name, value
340			T_ARG, // 3 : arg
341	root	1.1	T_DIR, // 4+: path
342			T_FILE, // 4+: path, data
343			T_NUM
344			};
345
346			enum
347			{
348			F_EXEC = 1,
349			F_LZF = 2,
350			F_NULL = 0
351			};
352
353			struct hdr
354			{
355			unsigned char type;
356			unsigned char flags;
357			unsigned char namelen[2];
358			unsigned char datalen[4];
359			};
360
361			struct tail {
362			unsigned char max_filesize[4];
363			unsigned char size[4];
364			char magic[12];
365			};
366
367			static char pack_base, pack_end;
368			static struct hdr *pack_cur;
369	root	1.2	static char *scratch;
370	root	1.6	static unsigned int scratch_size;
371	root	1.1
372			#define PACK_NAME ((char *)(pack_cur + 1))
373			#define PACK_DATA (PACK_NAME + u_16 (pack_cur->namelen) + 1)
374			#define PACK_VALID pack_cur->type
375
376			static void
377			pack_next (void)
378			{
379			unsigned int d = u_32 (pack_cur->datalen);
380
381			pack_cur = (struct hdr *)(PACK_DATA + d);
382			}
383
384			static void
385			pack_unmap (void)
386			{
387	root	1.6	if (pack_base)
388			{
389			u_munmap (pack_base, pack_end - pack_base);
390			pack_base = 0;
391			}
392	root	1.1
393	root	1.6	if (scratch)
394			{
395			u_free (scratch, scratch_size);
396			scratch = 0;
397			}
398	root	1.1	}
399
400			static int
401			pack_map (void)
402			{
403	root	1.6	char *addr;
404			unsigned int size;
405
406	root	1.1	#ifdef _WIN32
407			BY_HANDLE_FILE_INFORMATION fi;
408
409			if (!GetFileInformationByHandle (pack_handle, &fi))
410			return 0;
411
412	root	1.6	size = fi.nFileSizeLow;
413			#else
414			size = lseek (pack_handle, 0, SEEK_END);
415			#endif
416	root	1.1
417	root	1.6	addr = u_mmap (pack_handle, size);
418			if (!addr)
419	root	1.1	return 0;
420
421			pack_unmap ();
422
423	root	1.6	pack_base = addr;
424			pack_end = pack_base + size;
425	root	1.1
426			struct tail *tail;
427
428			tail = (void )(pack_end - sizeof (tail));
429
430			if (memcmp (tail->magic, TAIL_MAGIC, sizeof (TAIL_MAGIC) - 1))
431			return 0;
432
433			pack_cur = (struct hdr *)(pack_end - u_32 (tail->size));
434
435	root	1.6	scratch = u_malloc (scratch_size = u_32 (tail->max_filesize));
436			if (!scratch)
437			return 0;
438	root	1.2
439	root	1.1	return 1;
440			}
441
442			static void
443			exe_info (void)
444			{
445			if (!pack_map ())
446			fatal ("unable to locate packfile in executable - executable corrupted?");
447
448			if (pack_cur->type != T_META)
449			fatal ("unable to locate executable metadata - executable corrupted?");
450
451			strcpy (exe_id, PACK_NAME);
452			}
453
454			static void
455			load (void)
456			{
457			u_mkdir (datadir);
458
459			strcpy (exe_dir, datadir);
460			u_append (exe_dir, exe_id);
461			u_mkdir (exe_dir);
462
463			if (u_chdir (exe_dir))
464			fatal ("unable to change to application data directory");
465
466			u_handle h = u_open ("override");
467	root	1.5	if (u_valid (h))
468	root	1.1	{
469			u_handle oh = pack_handle;
470
471			pack_handle = h;
472			if (!pack_map ())
473			{
474			pack_handle = oh;
475			oh = h;
476			}
477
478			u_close (oh);
479			}
480
481			if (pack_cur->type != T_META)
482			fatal ("unable to locate override metadata");
483
484			strcpy (exe_ver, PACK_DATA);
485			pack_next ();
486
487	root	1.4	for (;;)
488	root	1.1	{
489	root	1.4	if (pack_cur->type == T_ENV)
490			u_setenv (PACK_NAME, PACK_DATA);
491			else if (pack_cur->type == T_ARG)
492	root	1.6	{
493			int len = u_16 (pack_cur->namelen) + 1;
494			exe_argv [exe_argc++] = exe_args + exe_argo;
495			memcpy (exe_args + exe_argo, PACK_NAME, len);
496			exe_argo += len;
497			}
498	root	1.4	else
499			break;
500	root	1.1
501			pack_next ();
502			}
503	root	1.4
504			done_env_arg:
505	root	1.1	strcpy (execdir, exe_dir);
506			u_append (execdir, "i-");
507			strcat (execdir, exe_ver);
508
509	root	1.6	strcat (strcpy (tmppath, execdir), ".lck");
510	root	1.7	lock_handle = u_lock (tmppath, 0, 1);
511	root	1.6	if (!lock_handle)
512	root	1.7	fatal ("unable to lock application instance");
513	root	1.6
514	root	1.1	if (access (execdir, F_OK))
515			{
516			// does not exist yet, so unpack and move
517			tmpdir (exe_dir);
518
519			if (u_chdir (tmppath))
520			fatal ("unable to change to new instance directory");
521
522			for (;;)
523			{
524			switch (pack_cur->type)
525			{
526			case T_DIR:
527			u_mkdir (PACK_NAME);
528			break;
529
530			case T_FILE:
531			{
532			u_handle h = u_creat (PACK_NAME, pack_cur->flags & F_EXEC);
533	root	1.2	unsigned int dlen, len = u_32 (pack_cur->datalen);
534			char *data = PACK_DATA;
535
536			if (pack_cur->flags & F_LZF)
537	root	1.6	if (dlen = lzf_decompress (data, len, scratch, scratch_size))
538	root	1.2	{
539			data = scratch;
540			len = dlen;
541			}
542			else
543			fatal ("unable to uncompress file data - pack corrupted?");
544	root	1.1
545	root	1.5	if (!u_valid (h))
546	root	1.1	fatal ("unable to unpack file from packfile - disk full?");
547
548	root	1.2	if (u_write (h, data, len) != len)
549	root	1.1	fatal ("unable to unpack file from packfile - disk full?");
550
551	root	1.4	u_fsync (h);
552	root	1.1	u_close (h);
553			}
554			break;
555
556			case T_NULL:
557			goto done;
558			}
559
560			pack_next ();
561			}
562
563			done:
564			if (u_chdir (datadir))
565			fatal ("unable to change to data directory");
566
567	root	1.3	u_sync ();
568
569	root	1.1	if (u_rename (tmppath, execdir))
570			deltree (tmppath); // if move fails, delete new, assume other process created it independently
571			}
572
573			pack_unmap ();
574			u_close (pack_handle);
575
576	root	1.2	if (u_chdir (execdir))
577			fatal ("unable to change to application instance directory");
578
579	root	1.1	u_setenv ("URLADER_VERSION", URLADER_VERSION);
580			u_setenv ("URLADER_DATADIR", datadir);
581			u_setenv ("URLADER_EXECDIR", execdir);
582			u_setenv ("URLADER_EXE_ID" , exe_id);
583			u_setenv ("URLADER_EXE_DIR", exe_dir);
584			u_setenv ("URLADER_EXE_VER", exe_ver);
585
586	root	1.5	#if 0
587	root	1.1	// yes, this is overkill
588			u_setenv ("SHLIB_PATH" , execdir); // hpux
589			u_setenv ("LIBPATH" , execdir); // aix
590			u_setenv ("LD_LIBRARY_PATH" , execdir); // most elf systems
591			u_setenv ("LD_LIBRARY_PATH_32", execdir); // solaris
592			u_setenv ("LD_LIBRARY_PATH_64", execdir); // solaris
593			u_setenv ("LD_LIBRARYN32_PATH", execdir); // irix
594			u_setenv ("LD_LIBRARY64_PATH" , execdir); // irix
595			u_setenv ("DYLD_LIBRARY_PATH" , execdir); // os sucks from apple
596	root	1.5	#endif
597	root	1.1	}
598
599	root	1.2	static void
600			execute (void)
601			{
602			exe_argv [exe_argc] = 0;
603	root	1.6	systemv (exe_argv);
604	root	1.2	}
605
606	root	1.1	#ifdef _WIN32
607
608			int APIENTRY
609			WinMain (HINSTANCE hI, HINSTANCE hP, LPSTR argv, int command_show)
610			{
611			if (!GetModuleFileName (hI, tmppath, sizeof (tmppath)))
612			fatal ("unable to find executable pack");
613
614	root	1.5	pack_handle = u_open (tmppath);
615			if (!u_valid (pack_handle))
616	root	1.1	fatal ("unable to open executable pack");
617
618			exe_info ();
619
620			if (!GetCurrentDirectory (sizeof (currdir), currdir))
621			strcpy (currdir, ".");
622
623			if (SHGetFolderPath (0, CSIDL_APPDATA \| CSIDL_FLAG_CREATE, NULL, SHGFP_TYPE_CURRENT, datadir) != S_OK)
624			fatal ("unable to find application data directory");
625
626			u_mkdir (datadir);
627			u_append (datadir, URLADER);
628
629			load ();
630			execute ();
631
632			return 0;
633			}
634
635			#else
636
637			int
638			main (int argc, char *argv[])
639			{
640			char *home = getenv ("HOME");
641
642	root	1.5	pack_handle = u_open (argv [0]);
643			if (!u_valid (pack_handle))
644	root	1.1	fatal ("unable to open executable pack");
645
646			exe_info ();
647
648			if (!home)
649			{
650			struct passwd *pw;
651
652			if ((pw = getpwuid (getuid ())))
653			home = pw->pw_dir;
654			else
655			home = "/tmp";
656			}
657
658			if (!getcwd (currdir, sizeof (currdir)))
659			strcpy (currdir, ".");
660
661			u_mkdir (home);
662	root	1.6	//strcat (strcat (strcpy (datadir, home), "/."), URLADER);
663	root	1.1	sprintf (datadir, "%s/.%s", home, URLADER);
664			u_mkdir (datadir);
665
666	root	1.5	#if 0
667	root	1.1	if (gethostname (tmppath, sizeof (tmppath)))
668			strcpy (tmppath, "default");
669
670			u_append (datadir, tmppath);
671	root	1.5	#endif
672	root	1.1
673			load ();
674			execute ();
675
676			return 0;
677			}
678
679			#endif
680