Mercurial > hg > octave-nkf > gnulib-hg
changeset 2627:308ad15a7eab
(xgetcwd): If the required pathname length is smaller
than 1024, return a memory chunk of least possible size, instead
of size PATH_MAX + 2. In the loop, increment the size proportionally.
Use free/xmalloc instead of xrealloc to avoid copying for very long paths.
author | Jim Meyering <jim@meyering.net> |
---|---|
date | Wed, 21 Jun 2000 20:16:03 +0000 |
parents | 1710f067f0d1 |
children | 7b2246aaa293 |
files | lib/xgetcwd.c |
diffstat | 1 files changed, 28 insertions(+), 22 deletions(-) [+] |
line wrap: on
line diff
--- a/lib/xgetcwd.c +++ b/lib/xgetcwd.c @@ -1,5 +1,5 @@ /* xgetcwd.c -- return current directory with unlimited length - Copyright (C) 1992, 1996 Free Software Foundation, Inc. + Copyright (C) 1992, 1996, 2000 Free Software Foundation, Inc. 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 @@ -37,12 +37,9 @@ # define getcwd(Buf, Max) getwd (Buf) #endif -/* Amount to increase buffer size by in each try. */ -#define PATH_INCR 32 - -char *xmalloc (); -char *xrealloc (); -void free (); +extern void *xmalloc (); +extern char *xstrdup (); +extern void free (); /* Return the current directory, newly allocated, arbitrarily long. Return NULL and set errno on error. */ @@ -50,30 +47,39 @@ char * xgetcwd () { - char *cwd; char *ret; unsigned path_max; + char buf[1024]; errno = 0; + ret = getcwd (buf, sizeof (buf)); + if (ret != NULL) + return xstrdup (buf); + if (errno != ERANGE) + return NULL; + path_max = (unsigned) PATH_MAX; path_max += 2; /* The getcwd docs say to do this. */ - cwd = xmalloc (path_max); - - errno = 0; - while ((ret = getcwd (cwd, path_max)) == NULL && errno == ERANGE) + for (;;) { - path_max += PATH_INCR; - cwd = xrealloc (cwd, path_max); - errno = 0; - } + char *cwd = (char *) xmalloc (path_max); - if (ret == NULL) - { - int save_errno = errno; + errno = 0; + ret = getcwd (cwd, path_max); + if (ret != NULL) + return ret; + if (errno != ERANGE) + { + int save_errno = errno; + free (cwd); + errno = save_errno; + return NULL; + } + free (cwd); - errno = save_errno; - return NULL; + + path_max += path_max / 16; + path_max += 32; } - return cwd; }