Fix the !HAVE_GETCWD_NULL code to behave more

[gnulib.git] / lib / xgetcwd.c

diff --git a/lib/xgetcwd.c b/lib/xgetcwd.c
index 55e12af..85ac368 100644 (file)
--- a/lib/xgetcwd.c
+++ b/lib/xgetcwd.c
@@ -39,41 +39,50 @@ extern int errno;
 #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
 
-#include "xalloc.h"
-
 /* Return the current directory, newly allocated, arbitrarily long.
    Return NULL and set errno on error. */
 
 char *
 xgetcwd ()
 {
-#if defined __GLIBC__ && __GLIBC__ >= 2
+#if HAVE_GETCWD_NULL
   return getcwd (NULL, 0);
 #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);
-
+      char *cwd;
+      int saved_errno;
+      char *buf = malloc (buf_size);
+      if (! buf)
+       return NULL;
       cwd = getcwd (buf, buf_size);
-      if (cwd != NULL)
+      if (cwd)
        return cwd;
-      if (errno != ERANGE)
+      saved_errno = errno;
+      free (buf);
+      if (saved_errno != ERANGE)
+       return NULL;
+      buf_size *= 2;
+      if (buf_size == 0)
        {
-         free (buf);
+         errno = ENOMEM;
          return NULL;
        }
-
-      buf_size *= 2;
-      if (buf_size == 0)
-       xalloc_die ();
     }
 #endif
 }