changeset 3452:baf8d5fe777a

Fix the !HAVE_GETCWD_NULL code to behave more like the HAVE_GETCWD_NULL code. Include pathmax.h if not HAVE_GETCWD. Do not include xalloc.h. (INITIAL_BUFFER_SIZE): New symbol. Do not use xmalloc / xrealloc, since the caller is responsible for handling errors. Preserve errno around `free' during failure. Do not overrun buffer when using getwd.
author Jim Meyering <jim@meyering.net>
date Mon, 03 Sep 2001 18:21:53 +0000
parents c613b4d20a05
children f584fe45f97f
files lib/xgetcwd.c
diffstat 1 files changed, 22 insertions(+), 13 deletions(-) [+]
line wrap: on
line diff
--- a/lib/xgetcwd.c
+++ b/lib/xgetcwd.c
@@ -39,12 +39,12 @@
 #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. */
 
@@ -54,26 +54,35 @@
 #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 *cwd;
-      buf = (char *) xrealloc (buf, buf_size);
-
+      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
 }