[deliverable/binutils-gdb.git] / libiberty / getpwd.c

/* getpwd.c - get the working directory */

/*

@deftypefn Supplemental char* getpwd (void)

Returns the current working directory.  This implementation caches the
result on the assumption that the process will not call @code{chdir}
between calls to @code{getpwd}.

@end deftypefn

*/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <sys/types.h>

#include <errno.h>
#ifndef errno
extern int errno;
#endif

#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#if HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#if HAVE_LIMITS_H
#include <limits.h>
#endif

/* Prototype these in case the system headers don't provide them. */
extern char *getpwd ();
extern char *getwd ();

#include "libiberty.h"

/* Virtually every UN*X system now in common use (except for pre-4.3-tahoe
   BSD systems) now provides getcwd as called for by POSIX.  Allow for
   the few exceptions to the general rule here.  */

#if !defined(HAVE_GETCWD) && defined(HAVE_GETWD)
#define getcwd(buf,len) getwd(buf)
#endif

#ifdef MAXPATHLEN
#define GUESSPATHLEN (MAXPATHLEN + 1)
#else
#define GUESSPATHLEN 100
#endif

#if !(defined (VMS) || (defined(_WIN32) && !defined(__CYGWIN__)))

/* Get the working directory.  Use the PWD environment variable if it's
   set correctly, since this is faster and gives more uniform answers
   to the user.  Yield the working directory if successful; otherwise,
   yield 0 and set errno.  */

char *
getpwd (void)
{
  static char *pwd;
  static int failure_errno;

  char *p = pwd;
  size_t s;
  struct stat dotstat, pwdstat;

  if (!p && !(errno = failure_errno))
    {
      if (! ((p = getenv ("PWD")) != 0
	     && *p == '/'
	     && stat (p, &pwdstat) == 0
	     && stat (".", &dotstat) == 0
	     && dotstat.st_ino == pwdstat.st_ino
	     && dotstat.st_dev == pwdstat.st_dev))

	/* The shortcut didn't work.  Try the slow, ``sure'' way.  */
	for (s = GUESSPATHLEN;  ! getcwd (p = xmalloc (s), s);  s *= 2)
	  {
	    int e = errno;
	    free (p);
#ifdef ERANGE
	    if (e != ERANGE)
#endif
	      {
		errno = failure_errno = e;
		p = 0;
		break;
	      }
	  }

      /* Cache the result.  This assumes that the program does
	 not invoke chdir between calls to getpwd.  */
      pwd = p;
    }
  return p;
}

#else	/* VMS || _WIN32 && !__CYGWIN__ */

#ifndef MAXPATHLEN
#define MAXPATHLEN 255
#endif

char *
getpwd (void)
{
  static char *pwd = 0;

  if (!pwd)
    pwd = getcwd (xmalloc (MAXPATHLEN + 1), MAXPATHLEN + 1
#ifdef VMS
		  , 0
#endif
		  );
  return pwd;
}

#endif	/* VMS || _WIN32 && !__CYGWIN__ */
Commit	Line	Data
e2eaf477 ILT	1	/* getpwd.c - get the working directory */
e2eaf477 ILT	2
39423523 DD	3	/*
39423523 DD	4
99b58139	5	@deftypefn Supplemental char* getpwd (void)
39423523 DD	6
	7	Returns the current working directory. This implementation caches the
	8	result on the assumption that the process will not call @code{chdir}
	9	between calls to @code{getpwd}.
	10
	11	@end deftypefn
	12
	13	*/
	14
e2eaf477 ILT	15	#ifdef HAVE_CONFIG_H
	16	#include "config.h"
	17	#endif
	18
	19	#include <sys/types.h>
	20
	21	#include <errno.h>
	22	#ifndef errno
	23	extern int errno;
	24	#endif
	25
	26	#ifdef HAVE_STDLIB_H
	27	#include <stdlib.h>
	28	#endif
	29	#ifdef HAVE_UNISTD_H
	30	#include <unistd.h>
	31	#endif
	32	#ifdef HAVE_SYS_PARAM_H
	33	#include <sys/param.h>
	34	#endif
	35	#if HAVE_SYS_STAT_H
	36	#include <sys/stat.h>
	37	#endif
37254c9a DD	38	#if HAVE_LIMITS_H
	39	#include <limits.h>
	40	#endif
e2eaf477 ILT	41
	42	/* Prototype these in case the system headers don't provide them. */
	43	extern char *getpwd ();
	44	extern char *getwd ();
	45
	46	#include "libiberty.h"
	47
	48	/* Virtually every UN*X system now in common use (except for pre-4.3-tahoe
	49	BSD systems) now provides getcwd as called for by POSIX. Allow for
	50	the few exceptions to the general rule here. */
	51
	52	#if !defined(HAVE_GETCWD) && defined(HAVE_GETWD)
	53	#define getcwd(buf,len) getwd(buf)
	54	#endif
	55
	56	#ifdef MAXPATHLEN
	57	#define GUESSPATHLEN (MAXPATHLEN + 1)
	58	#else
	59	#define GUESSPATHLEN 100
	60	#endif
	61
	62	#if !(defined (VMS) \|\| (defined(_WIN32) && !defined(__CYGWIN__)))
	63
	64	/* Get the working directory. Use the PWD environment variable if it's
	65	set correctly, since this is faster and gives more uniform answers
	66	to the user. Yield the working directory if successful; otherwise,
	67	yield 0 and set errno. */
	68
	69	char *
49b1fae4	70	getpwd (void)
e2eaf477 ILT	71	{
	72	static char *pwd;
	73	static int failure_errno;
	74
	75	char *p = pwd;
	76	size_t s;
	77	struct stat dotstat, pwdstat;
	78
	79	if (!p && !(errno = failure_errno))
	80	{
	81	if (! ((p = getenv ("PWD")) != 0
	82	&& *p == '/'
	83	&& stat (p, &pwdstat) == 0
	84	&& stat (".", &dotstat) == 0
	85	&& dotstat.st_ino == pwdstat.st_ino
	86	&& dotstat.st_dev == pwdstat.st_dev))
	87
	88	/* The shortcut didn't work. Try the slow, ``sure'' way. */
	89	for (s = GUESSPATHLEN; ! getcwd (p = xmalloc (s), s); s *= 2)
	90	{
	91	int e = errno;
	92	free (p);
	93	#ifdef ERANGE
	94	if (e != ERANGE)
	95	#endif
	96	{
	97	errno = failure_errno = e;
	98	p = 0;
	99	break;
	100	}
	101	}
	102
	103	/* Cache the result. This assumes that the program does
	104	not invoke chdir between calls to getpwd. */
	105	pwd = p;
	106	}
	107	return p;
	108	}
	109
	110	#else /* VMS \|\| _WIN32 && !__CYGWIN__ */
	111
	112	#ifndef MAXPATHLEN
	113	#define MAXPATHLEN 255
	114	#endif
	115
	116	char *
49b1fae4	117	getpwd (void)
e2eaf477 ILT	118	{
	119	static char *pwd = 0;
	120
	121	if (!pwd)
	122	pwd = getcwd (xmalloc (MAXPATHLEN + 1), MAXPATHLEN + 1
	123	#ifdef VMS
	124	, 0
	125	#endif
	126	);
	127	return pwd;
	128	}
	129
	130	#endif /* VMS \|\| _WIN32 && !__CYGWIN__ */