[Libsysio-commit] HEAD: libsysio/src inode.c

[Lee W. <lw...@us...>]

Update of /cvsroot/libsysio/libsysio/src
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv1705

Modified Files:
	inode.c 
Log Message:


Four changes:

1) The routine _sysio_p_path was moved here from chdir.c
2) A new routine, _sysio_p_show, is implemented when P_DEBUG is defined.
3) _sysio_p_find_alias prints the pnode when P_DEBUG is defined, using
_sysio_p_show.
4) _sysio_gone prints the pnode when P_DEBUG is defined, using _sysio_p_show.


Index: inode.c
===================================================================
RCS file: /cvsroot/libsysio/libsysio/src/inode.c,v
retrieving revision 1.37
retrieving revision 1.38
diff -u -w -b -B -p -r1.37 -r1.38
--- inode.c	31 Mar 2008 16:33:55 -0000	1.37
+++ inode.c	14 Apr 2008 23:28:41 -0000	1.38
@@ -623,6 +623,100 @@ _sysio_i_shutdown()
 #endif
 
 /*
+ * Return path tracked by the path ancestor chain.
+ *
+ * If the buf pointer is NULL, a buffer large enough to hold the path
+ * is allocated from the heap.
+ */
+
+int
+_sysio_p_path(struct pnode *pno, char **bufp, size_t size)
+{
+	struct pnode *cur;
+	size_t	len;
+	size_t	n;
+	char	*cp;
+
+	cur = pno;
+
+	if (!size && bufp && *bufp)
+		return -EINVAL;
+
+	/*
+	 * Walk up the tree to the root, summing the component name
+	 * lengths and counting the vertices.
+	 */
+	len = 0;
+	n = 0;
+	do {
+		/*
+		 * If this is a covering path-node then the name should be
+		 * the *covered* nodes name, not this one unless we are at
+		 * the root of the name-space.
+		 */
+		while (pno == pno->p_mount->mnt_root &&
+		       pno != pno->p_parent)
+			pno = pno->p_mount->mnt_covers;
+
+		/*
+		 * Add length of this component to running sum and
+		 * account for this vertex.
+		 */
+		assert((len >= pno->p_base->pb_key.pbk_name.len &&
+			(size_t )~0 - pno->p_base->pb_key.pbk_name.len > len) ||
+		       (size_t )~0 - len > pno->p_base->pb_key.pbk_name.len);
+		len += pno->p_base->pb_key.pbk_name.len;
+		n++;
+		assert(n);
+		pno = pno->p_parent;
+	} while (pno && pno != pno->p_parent);
+	if (!pno)
+		return -ENOENT;
+
+	if (!*bufp)
+		size = len + n + 1;
+	if (len >= size || n >= size - len)
+		return -ERANGE;
+	if (!*bufp) {
+		/*
+		 * Allocate path buffer from the heap.
+		 */
+		*bufp = malloc(size * sizeof(char));
+		if (!*bufp)
+			return -ENOMEM;
+	}
+
+	/*
+	 * Fill in the path buffer.
+	 */
+	pno = cur;
+	cp = *bufp + len + n;
+	*cp = '\0';					/* NUL terminate */
+	do {
+		/*
+		 * If this is a covering path-node then the name should be
+		 * the *covered* nodes name, not this one unless we are at
+		 * the root of the name-space.
+		 */
+		while (pno == pno->p_mount->mnt_root &&
+		       pno != pno->p_parent )
+			pno = pno->p_mount->mnt_covers;
+
+		/*
+		 * Add component and separator.
+		 */
+		cp -= pno->p_base->pb_key.pbk_name.len;
+		(void )memcpy(cp, pno->p_base->pb_key.pbk_name.name,
+			      pno->p_base->pb_key.pbk_name.len);
+
+		*--cp = PATH_SEPARATOR;
+		pno = pno->p_parent;
+	} while (pno != pno->p_parent);
+
+	return 0;
+}
+
+/*
  * Allocate, initialize and establish appropriate links for new path (alias)
  * node.
  */
@@ -649,6 +743,88 @@ _sysio_p_new_alias(struct pnode *parent,
 	return pno;
 }
 
+#ifdef P_DEBUG
+/*
+ * Thread-safe strerror.
+ *
+ * Returns string describing the passed error number or NULL on failure.
+ */
+static char *
+x_strerror(int err)
+{
+	char	*s;
+	size_t	buflen;
+	void	*p;
+	int	myerr;
+
+	s = NULL;
+	buflen = 16;
+	for (;;) {
+		buflen <<= 1;
+		p = realloc(s, buflen);
+		if (!p)
+			free(s);
+		s = p;
+		if (!s)
+			break;
+		myerr = 0;
+#if defined(_XOPEN_SOURCE) && _XOPEN_SOURCE >= 600
+		if (strerror_r(err, s, buflen) != 0)
+			myerr = errno;
+#elif defined(__GNU__)
+		 {
+			p = strerror_r(err, s, buflen);
+			if (!p)
+				myerr = EINVAL;
+			else if (p != s) {
+				(void )strncpy(s, (char *)p, buflen - 1);
+				s[buflen = 1] = '\0';
+			}
+			if (!myerr && strlen(s) == buflen - 1)
+				myerr = ERANGE;
+		}
+#else
+#error I do not know whtat strerror_r returns
+#endif
+		if (!myerr)
+			break;
+		if (myerr == ERANGE)
+			continue;
+		free(s);
+		s = NULL;
+		errno = myerr;
+		break;
+	}
+	return s;
+}
+
+void
+_sysio_p_show(const char *pre, struct pnode *pno)
+{
+	int	err;
+	char	*path;
+	static char error_message[] = "<ERROR>";
+
+	path = NULL;
+	if ((err = _sysio_p_path(pno, &path, 0)) != 0) {
+		char	*s;
+
+		s = x_strerror(-err);
+		if (!s ||(path = malloc(strlen(s) + 2 + 1)) == NULL) {
+			if (s)
+				free(s);
+			path = error_message;
+		} else {
+			(void )sprintf(path, "<%s>", s);
+			free(s);
+		}
+	}
+	_sysio_diag_printf(pre, "%x:%x %s\n", pno->p_mount, pno, path);
+	if (path != error_message)
+		free(path);
+}
+#endif
+
 /*
  * For reclamation of idle path (alias) node.
  */
@@ -658,6 +834,9 @@ _sysio_p_gone(struct pnode *pno)
 	assert(!pno->p_ref);
 	assert(!pno->p_cover);
 
+#ifdef P_DEBUG
+	_sysio_p_show("P_GONE", pno);
+#endif
 	TAILQ_REMOVE(&_sysio_idle_pnodes, pno, p_idle);
 	LIST_REMOVE(pno, p_links);
 
@@ -758,8 +937,12 @@ _sysio_p_find_alias(struct pnode *parent
 		if (!pno)
 			err = -ENOMEM;
 	}
-	if (!err)
+	if (!err) {
+#ifdef P_DEBUG
+		_sysio_p_show("P_FIND_ALIAS", pno);
+#endif
 		*pnop = pno;
+	}
 	return err;
 }