util.c

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#else
/*VARARGS1*/ void
say (format, va_alist)
     char const *format;
     va_dcl
#endif
{
  va_list args;
  vararg_start (args, format);
  vfprintf (stdout, format, args);
  va_end (args);
  fflush (stdout);
}

/* Get a response from the user, somehow or other. */

#ifdef __STDC__
void
ask (char const *format, ...)
#else
/*VARARGS1*/ void
ask (format, va_alist)
     char const *format;
     va_dcl
#endif
{
  static int ttyfd = -2;
  int r;
  va_list args;

  vararg_start (args, format);
  vfprintf (stdout, format, args);
  va_end (args);
  fflush (stdout);

  if (ttyfd == -2)
    {
      /* If standard output is not a tty, don't bother opening /dev/tty,
	 since it's unlikely that stdout will be seen by the tty user.
	 The isatty test also works around a bug in GNU Emacs 19.34 under Linux
	 which makes a call-process `patch' hang when it reads from /dev/tty.
	 POSIX.2 requires that we read /dev/tty, though.  */
      ttyfd = (posixly_correct || isatty (STDOUT_FILENO)
	       ? open (TTY_DEVICE, O_RDONLY)
	       : -1);
    }

  if (ttyfd < 0)
    {
      /* No terminal at all -- default it.  */
      printf ("\n");
      buf[0] = '\n';
      buf[1] = '\0';
    }
  else
    {
      size_t s = 0;
      while ((r = read (ttyfd, buf + s, bufsize - 1 - s)) == bufsize - 1 - s
	     && buf[bufsize - 2] != '\n')
	{
	  s = bufsize - 1;
	  bufsize *= 2;
	  buf = realloc (buf, bufsize);
	  if (!buf)
	    memory_fatal ();
	}
      if (r == 0)
	printf ("EOF\n");
      else if (r < 0)
	{
	  perror ("tty read");
	  fflush (stderr);
	  close (ttyfd);
	  ttyfd = -1;
	  r = 0;
	}
      buf[s + r] = '\0';
    }
}

/* Return nonzero if it OK to reverse a patch.  */

#ifdef __STDC__
int
ok_to_reverse (char const *format, ...)
#else
ok_to_reverse (format, va_alist)
     char const *format;
     va_dcl
#endif
{
  int r = 0;

  if (noreverse || ! (force && verbosity == SILENT))
    {
      va_list args;
      vararg_start (args, format);
      vfprintf (stdout, format, args);
      va_end (args);
    }

  if (noreverse)
    {
      printf ("  Skipping patch.\n");
      skip_rest_of_patch = TRUE;
      r = 0;
    }
  else if (force)
    {
      if (verbosity != SILENT)
	printf ("  Applying it anyway.\n");
      r = 0;
    }
  else if (batch)
    {
      say (reverse ? "  Ignoring -R.\n" : "  Assuming -R.\n");
      r = 1;
    }
  else
    {
      ask (reverse ? "  Ignore -R? [n] " : "  Assume -R? [n] ");
      r = *buf == 'y';
      if (! r)
	{
	  ask ("Apply anyway? [n] ");
	  if (*buf != 'y')
	    {
	      if (verbosity != SILENT)
		say ("Skipping patch.\n");
	      skip_rest_of_patch = TRUE;
	    }
	}
    }

  return r;
}

/* How to handle certain events when not in a critical region. */

#define NUM_SIGS (sizeof (sigs) / sizeof (*sigs))
static int const sigs[] = {
#ifdef SIGHUP
       SIGHUP,
#endif
#ifdef SIGPIPE
       SIGPIPE,
#endif
#ifdef SIGTERM
       SIGTERM,
#endif
#ifdef SIGXCPU
       SIGXCPU,
#endif
#ifdef SIGXFSZ
       SIGXFSZ,
#endif
       SIGINT
};

#if !HAVE_SIGPROCMASK
#define sigset_t int
#define sigemptyset(s) (*(s) = 0)
#ifndef sigmask
#define sigmask(sig) (1 << ((sig) - 1))
#endif
#define sigaddset(s, sig) (*(s) |= sigmask (sig))
#define sigismember(s, sig) ((*(s) & sigmask (sig)) != 0)
#ifndef SIG_BLOCK
#define SIG_BLOCK 0
#endif
#ifndef SIG_UNBLOCK
#define SIG_UNBLOCK (SIG_BLOCK + 1)
#endif
#ifndef SIG_SETMASK
#define SIG_SETMASK (SIG_BLOCK + 2)
#endif
#define sigprocmask(how, n, o) \
  ((how) == SIG_BLOCK \
   ? ((o) ? *(o) = sigblock (*(n)) : sigblock (*(n))) \
   : (how) == SIG_UNBLOCK \
   ? sigsetmask (((o) ? *(o) = sigblock (0) : sigblock (0)) & ~*(n)) \
   : (o ? *(o) = sigsetmask (*(n)) : sigsetmask (*(n))))
#if !HAVE_SIGSETMASK
#define sigblock(mask) 0
#define sigsetmask(mask) 0
#endif
#endif

static sigset_t initial_signal_mask;
static sigset_t signals_to_block;

#if ! HAVE_SIGACTION
static RETSIGTYPE fatal_exit_handler PARAMS ((int)) __attribute__ ((noreturn));
static RETSIGTYPE
fatal_exit_handler (sig)
     int sig;
{
  signal (sig, SIG_IGN);
  fatal_exit (sig);
}
#endif

void
set_signals(reset)
int reset;
{
  int i;
#if HAVE_SIGACTION
  struct sigaction initial_act, fatal_act;
  fatal_act.sa_handler = fatal_exit;
  sigemptyset (&fatal_act.sa_mask);
  fatal_act.sa_flags = 0;
#define setup_handler(sig) sigaction (sig, &fatal_act, (struct sigaction *) 0)
#else
#define setup_handler(sig) signal (sig, fatal_exit_handler)
#endif

  if (!reset)
    {
#ifdef SIGCHLD
      /* System V fork+wait does not work if SIGCHLD is ignored.  */
      signal (SIGCHLD, SIG_DFL);
#endif
      sigemptyset (&signals_to_block);
      for (i = 0;  i < NUM_SIGS;  i++)
	{
	  int ignoring_signal;
#if HAVE_SIGACTION
	  if (sigaction (sigs[i], (struct sigaction *) 0, &initial_act) != 0)
	    continue;
	  ignoring_signal = initial_act.sa_handler == SIG_IGN;
#else
	  ignoring_signal = signal (sigs[i], SIG_IGN) == SIG_IGN;
#endif
	  if (! ignoring_signal)
	    {
	      sigaddset (&signals_to_block, sigs[i]);
	      setup_handler (sigs[i]);
	    }
	}
    }
  else
    {
      /* Undo the effect of ignore_signals.  */
#if HAVE_SIGPROCMASK || HAVE_SIGSETMASK
      sigprocmask (SIG_SETMASK, &initial_signal_mask, (sigset_t *) 0);
#else
      for (i = 0;  i < NUM_SIGS;  i++)
	if (sigismember (&signals_to_block, sigs[i]))
	  setup_handler (sigs[i]);
#endif
    }
}

/* How to handle certain events when in a critical region. */

void
ignore_signals()
{
#if HAVE_SIGPROCMASK || HAVE_SIGSETMASK
  sigprocmask (SIG_BLOCK, &signals_to_block, &initial_signal_mask);
#else
  int i;
  for (i = 0;  i < NUM_SIGS;  i++)
    if (sigismember (&signals_to_block, sigs[i]))
      signal (sigs[i], SIG_IGN);
#endif
}

void
exit_with_signal (sig)
     int sig;
{
  sigset_t s;
  signal (sig, SIG_DFL);
  sigemptyset (&s);
  sigaddset (&s, sig);
  sigprocmask (SIG_UNBLOCK, &s, (sigset_t *) 0);
  raise (sig);
  exit (2);
}

int
systemic (command)
     char const *command;
{
  if (debug & 8)
    say ("+ %s\n", command);
  fflush (stdout);
  return system (command);
}

#if !HAVE_MKDIR
/* These mkdir and rmdir substitutes are good enough for `patch';
   they are not general emulators.  */

static int doprogram PARAMS ((char const *, char const *));
static int mkdir PARAMS ((char const *, mode_t));
static int rmdir PARAMS ((char const *));

static int
doprogram (program, arg)
     char const *program;
     char const *arg;
{
  int result;
  static char const DISCARD_OUTPUT[] = " 2>/dev/null";
  size_t program_len = strlen (program);
  char *cmd = xmalloc (program_len + 1 + quote_system_arg (0, arg)
		       + sizeof DISCARD_OUTPUT);
  char *p = cmd;
  strcpy (p, program);
  p += program_len;
  *p++ = ' ';
  p += quote_system_arg (p, arg);
  strcpy (p, DISCARD_OUTPUT);
  result = systemic (cmd);
  free (cmd);
  return result;
}

#ifdef __STDC__
/* If mode_t doesn't promote to itself, we can't use old-style definition.  */
static int
mkdir (char const *path, mode_t mode)
#else
static int
mkdir (path, mode)
     char const *path;
     mode_t mode; /* ignored */
#endif
{
  return doprogram ("mkdir", path);
}

static int
rmdir (path)
     char const *path;
{
  int result = doprogram ("rmdir", path);
  errno = EEXIST;
  return result;
}
#endif

/* Replace '/' with '\0' in FILENAME if it marks a place that
   needs testing for the existence of directory.  Return the address
   of the last location replaced, or 0 if none were replaced.  */
static char *replace_slashes PARAMS ((char *));
static char *
replace_slashes (filename)
     char *filename;
{
  char *f;
  char *last_location_replaced = 0;
  char const *component_start;

  for (f = filename + FILESYSTEM_PREFIX_LEN (filename);  ISSLASH (*f);  f++)
    continue;

  component_start = f;

  for (; *f; f++)
    if (ISSLASH (*f))
      {
	char *slash = f;

	/* Treat multiple slashes as if they were one slash.  */
	while (ISSLASH (f[1]))
	  f++;

	/* Ignore slashes at the end of the path.  */
	if (! f[1])
	  break;

	/* "." and ".." need not be tested.  */
	if (! (slash - component_start <= 2
	       && component_start[0] == '.' && slash[-1] == '.'))
	  {
	    *slash = '\0';
	    last_location_replaced = slash;
	  }

	component_start = f + 1;
      }

  return last_location_replaced;
}

/* Make sure we'll have the directories to create a file.
   Ignore the last element of `filename'.  */

static void
makedirs (filename)
     register char *filename;
{
  register char *f;
  register char *flim = replace_slashes (filename);

  if (flim)
    {
      /* Create any missing directories, replacing NULs by '/'s.
	 Ignore errors.  We may have to keep going even after an EEXIST,
	 since the path may contain ".."s; and when there is an EEXIST
	 failure the system may return some other error number.
	 Any problems will eventually be reported when we create the file.  */
      for (f = filename;  f <= flim;  f++)
	if (!*f)
	  {
	    mkdir (filename,
		   S_IRUSR|S_IWUSR|S_IXUSR
		   |S_IRGRP|S_IWGRP|S_IXGRP
		   |S_IROTH|S_IWOTH|S_IXOTH);
	    *f = '/';
	  }
    }
}

/* Remove empty ancestor directories of FILENAME.
   Ignore errors, since the path may contain ".."s, and when there
   is an EEXIST failure the system may return some other error number.  */
void
removedirs (filename)
     char *filename;
{
  size_t i;

  for (i = strlen (filename);  i != 0;  i--)
    if (ISSLASH (filename[i])
	&& ! (ISSLASH (filename[i - 1])
	      || (filename[i - 1] == '.'
		  && (i == 1
		      || ISSLASH (filename[i - 2])
		      || (filename[i - 2] == '.'
			  && (i == 2
			      || ISSLASH (filename[i - 3])))))))
      {
	filename[i] = '\0';
	if (rmdir (filename) == 0 && verbosity == VERBOSE)
	  say ("Removed empty directory `%s'.\n", filename);
	filename[i] = '/';
      }
}

static time_t initial_time;

void
init_time ()
{
  time (&initial_time);
}

/* Make filenames more reasonable. */

char *
fetchname (at, strip_leading, pstamp)
char *at;
int strip_leading;
time_t *pstamp;
{
    char *name;
    register char *t;
    int sleading = strip_leading;
    time_t stamp = (time_t) -1;

    while (ISSPACE ((unsigned char) *at))
	at++;
    if (debug & 128)
	say ("fetchname %s %d\n", at, strip_leading);

    name = at;
    /* Strip off up to `sleading' leading slashes and null terminate.  */
    for (t = at;  *t;  t++)
      {
	if (ISSLASH (*t))
	  {
	    while (ISSLASH (t[1]))
	      t++;
	    if (--sleading >= 0)
		name = t+1;
	  }
	else if (ISSPACE ((unsigned char) *t))
	  {
	    if (set_time | set_utc)
	      stamp = str2time (t, initial_time, set_utc ? 0L : TM_LOCAL_ZONE);
	    else
	      {
		/* The head says the file is nonexistent if the timestamp
		   is the epoch; but the listed time is local time, not UTC,
		   and POSIX.1 allows local time to be 24 hours away from UTC.
		   So match any time within 24 hours of the epoch.
		   Use a default time zone 24 hours behind UTC so that any
		   non-zoned time within 24 hours of the epoch is valid.  */
		stamp = str2time (t, initial_time, -24L * 60 * 60);
		if (0 <= stamp && stamp <= 2 * 24L * 60 * 60)
		  stamp = 0;
	      }

	    *t = '\0';
	    break;
	  }
      }

    if (!*name)
      return 0;

    /* Allow files to be created by diffing against /dev/null.  */
    if (strcmp (at, "/dev/null") == 0)
      {
	if (pstamp)
	  *pstamp = 0;
	return 0;
      }

    if (pstamp)
      *pstamp = stamp;

    return savestr (name);
}

GENERIC_OBJECT *
xmalloc (size)
     size_t size;
{
  register GENERIC_OBJECT *p = malloc (size);
  if (!p)
    memory_fatal ();
  return p;
}

void
Fseek (stream, offset, ptrname)
     FILE *stream;
     file_offset offset;
     int ptrname;
{
  if (file_seek (stream, offset, ptrname) != 0)
    pfatal ("fseek");
}