#if HAVE_GETCWD
char *getcwd ();
#else
+# include "pathmax.h"
+# define INITIAL_BUFFER_SIZE (PATH_MAX + 1)
char *getwd ();
# define getcwd(Buf, Max) getwd (Buf)
#endif
char *
xgetcwd ()
{
-#if defined __GLIBC__ && __GLIBC__ >= 2
- return getcwd (NULL, 0);
+#if HAVE_GETCWD_NULL
+ char *cwd = getcwd (NULL, 0);
+ if (! cwd && errno == ENOMEM)
+ xalloc_die ();
+ return cwd;
#else
- size_t buf_size = 128; /* must be a power of 2 */
- char *buf = NULL;
+
+ /* The initial buffer size for the working directory. A power of 2
+ detects arithmetic overflow earlier, but is not required. */
+# ifndef INITIAL_BUFFER_SIZE
+# define INITIAL_BUFFER_SIZE 128
+# endif
+
+ size_t buf_size = INITIAL_BUFFER_SIZE;
while (1)
{
- char *ret;
- buf = (char *) xrealloc (buf, buf_size);
-
- cwd = getcwd (buf, buf_size);
- if (cwd != NULL)
+ char *buf = xmalloc (buf_size);
+ char *cwd = getcwd (buf, buf_size);
+ int saved_errno;
+ if (cwd)
return cwd;
- if (errno != ERANGE)
- {
- free (buf);
- return NULL;
- }
-
+ saved_errno = errno;
+ free (buf);
+ if (saved_errno != ERANGE)
+ return NULL;
buf_size *= 2;
if (buf_size == 0)
xalloc_die ();