Introduce upoke function

This will be needed to implement fault injection on those architectures
that lack PTRACE_SETREGSET/PTRACE_SETREGS support.

* defs.h (upoke): New prototype.
* upoke.c: New file.
* Makefile.am (libstrace_a_SOURCES): Add it.

diff --git a/Makefile.am b/Makefile.am
index eabed469baa4f2a2edb83734e5c80d123f7d71ce..e55a0db2183e7abc93c2b2c0bffabc9922ed2f33 100644 (file)
--- a/Makefile.am
+++ b/Makefile.am
@@ -73,6 +73,7 @@ libstrace_a_SOURCES = \
        sync_file_range.c \
        sync_file_range2.c \
        upeek.c         \
+       upoke.c         \
        # end of libstrace_a_SOURCES
 
 strace_SOURCES =       \

diff --git a/defs.h b/defs.h
index 1d989b2a5e32fb08e384d93348d1713c80d47852..ac61ea393eef86c22e5b1b3d2c8e9495c55e87e1 100644 (file)
--- a/defs.h
+++ b/defs.h
@@ -483,6 +483,7 @@ umoven_or_printaddr_ignore_syserror(struct tcb *tcp, const long addr,
                                    const unsigned int len, void *our_addr);
 extern int umovestr(struct tcb *, long, unsigned int, char *);
 extern int upeek(int pid, long, long *);
+extern int upoke(int pid, long, long);
 
 extern bool
 print_array(struct tcb *tcp,

diff --git a/upoke.c b/upoke.c
new file mode 100644 (file)
index 0000000..e22c1ee
--- /dev/null
+++ b/upoke.c
@@ -0,0 +1,40 @@
+/*
+ * Copyright (c) 2016 Dmitry V. Levin <ldv@altlinux.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "defs.h"
+#include "ptrace.h"
+
+int
+upoke(int pid, long off, long val)
+{
+       if (ptrace(PTRACE_POKEUSER, (pid_t) pid, (void *) off, (void *) val)) {
+               if (errno != ESRCH)
+                       perror_msg("upoke: PTRACE_POKEUSER pid:%d @%#lx)", pid, off);
+               return -1;
+       }
+       return 0;
+}