[src/trunk]: src/lib/librumphijack * avoid problems if the platform calls rea...

[pooka <pooka%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/41c364f17de7
branches:  trunk
changeset: 782109:41c364f17de7
user:      pooka <pooka%NetBSD.org@localhost>
date:      Tue Oct 16 12:56:10 2012 +0000

description:
* avoid problems if the platform calls readlink() from dlsym()
* alias __read_chk() to read() on Linux (technically, though,
  it should call host __read_chk() instead of read())

diffstat:

 lib/librumphijack/hijack.c |  43 +++++++++++++++++++++++++++++++++++--------
 1 files changed, 35 insertions(+), 8 deletions(-)

diffs (85 lines):

diff -r 996459b1b407 -r 41c364f17de7 lib/librumphijack/hijack.c
--- a/lib/librumphijack/hijack.c        Tue Oct 16 12:31:57 2012 +0000
+++ b/lib/librumphijack/hijack.c        Tue Oct 16 12:56:10 2012 +0000
@@ -1,4 +1,4 @@
-/*      $NetBSD: hijack.c,v 1.99 2012/09/12 10:35:10 martin Exp $      */
+/*      $NetBSD: hijack.c,v 1.100 2012/10/16 12:56:10 pooka Exp $      */
 
 /*-
  * Copyright (c) 2011 Antti Kantee.  All Rights Reserved.
@@ -31,7 +31,7 @@
 #include "rumpuser_port.h"
 
 #include <sys/cdefs.h>
-__RCSID("$NetBSD: hijack.c,v 1.99 2012/09/12 10:35:10 martin Exp $");
+__RCSID("$NetBSD: hijack.c,v 1.100 2012/10/16 12:56:10 pooka Exp $");
 
 #include <sys/param.h>
 #include <sys/types.h>
@@ -1769,7 +1769,8 @@
        int i, j;
        int rv, incr;
 
-       DPRINTF(("select\n"));
+       DPRINTF(("select %d %p %p %p %p\n", nfds,
+           readfds, writefds, exceptfds, timeout));
 
        /*
         * Well, first we must scan the fds to figure out how many
@@ -1949,7 +1950,7 @@
        nfds_t i;
        int rv;
 
-       DPRINTF(("poll\n"));
+       DPRINTF(("poll %p %d %p %p\n", fds, (int)nfds, ts, sigmask));
        checkpoll(fds, nfds, &hostcall, &rumpcall);
 
        if (hostcall && rumpcall) {
@@ -2287,6 +2288,11 @@
        (int, void *, size_t),                                          \
        (fd, buf, buflen))
 
+#ifdef __linux__
+ssize_t __read_chk(int, void *, size_t)
+    __attribute__((alias("read")));
+#endif
+
 FDCALL(ssize_t, readv, DUALCALL_READV,                                         \
        (int fd, const struct iovec *iov, int iovcnt),                  \
        (int, const struct iovec *, int),                               \
@@ -2438,10 +2444,31 @@
        (const char *, const char *),                                   \
        (target, path))
 
-PATHCALL(ssize_t, readlink, DUALCALL_READLINK,                         \
-       (const char *path, char *buf, size_t bufsiz),                   \
-       (const char *, char *, size_t),                                 \
-       (path, buf, bufsiz))
+/*
+ * readlink() can be called from malloc which can be called
+ * from dlsym() during init
+ */
+ssize_t
+readlink(const char *path, char *buf, size_t bufsiz)
+{
+       int (*op_readlink)(const char *, char *, size_t);
+       enum pathtype pt;
+
+       if ((pt = path_isrump(path)) != PATH_HOST) {
+               op_readlink = GETSYSCALL(rump, READLINK);
+               if (pt == PATH_RUMP)
+                       path = path_host2rump(path);
+       } else {
+               op_readlink = GETSYSCALL(host, READLINK);
+       }
+
+       if (__predict_false(op_readlink == NULL)) {
+               errno = ENOENT;
+               return -1;
+       }
+
+       return op_readlink(path, buf, bufsiz);
+}
 
 PATHCALL(int, mkdir, DUALCALL_MKDIR,                                   \
        (const char *path, mode_t mode),                                \