From patchwork Thu Apr 30 12:05:41 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gary Benson X-Patchwork-Id: 6501 Received: (qmail 79558 invoked by alias); 30 Apr 2015 12:05:54 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Delivered-To: mailing list gdb-patches@sourceware.org Received: (qmail 79422 invoked by uid 89); 30 Apr 2015 12:05:54 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.1 required=5.0 tests=AWL, BAYES_00, SPF_HELO_PASS, SPF_PASS, T_RP_MATCHES_RCVD autolearn=ham version=3.3.2 X-HELO: mx1.redhat.com Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES256-GCM-SHA384 encrypted) ESMTPS; Thu, 30 Apr 2015 12:05:52 +0000 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (Postfix) with ESMTPS id EABFF91746; Thu, 30 Apr 2015 12:05:50 +0000 (UTC) Received: from blade.nx (ovpn-116-76.ams2.redhat.com [10.36.116.76]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id t3UC5nCi000539; Thu, 30 Apr 2015 08:05:50 -0400 Received: from blade.nx (localhost [127.0.0.1]) by blade.nx (Postfix) with ESMTP id 312DD263E8B; Thu, 30 Apr 2015 13:05:48 +0100 (BST) From: Gary Benson To: gdb-patches@sourceware.org Cc: Eli Zaretskii , Pedro Alves , Doug Evans , =?UTF-8?q?Iago=20L=C3=B3pez=20Galeiras?= Subject: [PATCH 8/9 v2] Implement vFile:setfs in gdbserver Date: Thu, 30 Apr 2015 13:05:41 +0100 Message-Id: <1430395542-16017-9-git-send-email-gbenson@redhat.com> In-Reply-To: <1429186791-6867-1-git-send-email-gbenson@redhat.com> References: <1429186791-6867-1-git-send-email-gbenson@redhat.com> X-IsSubscribed: yes This commit implements the "vFile:setfs" packet in gdbserver. gdb/gdbserver/ChangeLog: * target.h (struct target_ops) : New field. : Likewise. : Likewise. * linux-low.c (nat/linux-namespaces.h): New include. (linux_target_ops): Initialize the_target->multifs_open, the_target->multifs_unlink and the_target->multifs_readlink. * hostio.c (hostio_fs_pid): New static variable. (handle_setfs): New function. (handle_open): Use the_target->multifs_open as appropriate. (handle_unlink): Use the_target->multifs_unlink as appropriate. (handle_readlink): Use the_target->multifs_readlink as appropriate. (handle_vFile): Handle vFile:setfs packets. --- gdb/gdbserver/ChangeLog | 16 +++++++++++ gdb/gdbserver/hostio.c | 62 ++++++++++++++++++++++++++++++++++++++++++-- gdb/gdbserver/linux-low.c | 4 +++ gdb/gdbserver/target.h | 21 +++++++++++++++ 4 files changed, 100 insertions(+), 3 deletions(-) diff --git a/gdb/gdbserver/hostio.c b/gdb/gdbserver/hostio.c index 9e858d9..10cff5a 100644 --- a/gdb/gdbserver/hostio.c +++ b/gdb/gdbserver/hostio.c @@ -243,6 +243,47 @@ hostio_reply_with_data (char *own_buf, char *buffer, int len, return input_index; } +/* Process ID of inferior whose filesystem hostio functions + that take FILENAME arguments will use. Zero means to use + our own filesystem. */ + +static int hostio_fs_pid = 0; + +/* Handle a "vFile:setfs:" packet. */ + +static void +handle_setfs (char *own_buf) +{ + char *p; + int pid; + + /* If the target doesn't have any of the in-filesystem-of methods + then there's no point in GDB sending "vFile:setfs:" packets. We + reply with an empty packet (i.e. we pretend we don't understand + "vFile:setfs:") and that should stop GDB sending any more. */ + if (the_target->multifs_open == NULL + && the_target->multifs_unlink == NULL + && the_target->multifs_readlink == NULL) + { + own_buf[0] = '\0'; + return; + } + + p = own_buf + strlen ("vFile:setfs:"); + + if (require_int (&p, &pid) + || pid < 0 + || require_end (p)) + { + hostio_packet_error (own_buf); + return; + } + + hostio_fs_pid = pid; + + hostio_reply (own_buf, 0); +} + static void handle_open (char *own_buf) { @@ -267,7 +308,11 @@ handle_open (char *own_buf) /* We do not need to convert MODE, since the fileio protocol uses the standard values. */ - fd = open (filename, flags, mode); + if (hostio_fs_pid != 0 && the_target->multifs_open != NULL) + fd = the_target->multifs_open (hostio_fs_pid, filename, + flags, mode); + else + fd = open (filename, flags, mode); if (fd == -1) { @@ -471,7 +516,10 @@ handle_unlink (char *own_buf) return; } - ret = unlink (filename); + if (hostio_fs_pid != 0 && the_target->multifs_unlink != NULL) + ret = the_target->multifs_unlink (hostio_fs_pid, filename); + else + ret = unlink (filename); if (ret == -1) { @@ -498,7 +546,13 @@ handle_readlink (char *own_buf, int *new_packet_len) return; } - ret = readlink (filename, linkname, sizeof (linkname) - 1); + if (hostio_fs_pid != 0 && the_target->multifs_readlink != NULL) + ret = the_target->multifs_readlink (hostio_fs_pid, filename, + linkname, + sizeof (linkname) - 1); + else + ret = readlink (filename, linkname, sizeof (linkname) - 1); + if (ret == -1) { hostio_error (own_buf); @@ -532,6 +586,8 @@ handle_vFile (char *own_buf, int packet_len, int *new_packet_len) handle_unlink (own_buf); else if (startswith (own_buf, "vFile:readlink:")) handle_readlink (own_buf, new_packet_len); + else if (startswith (own_buf, "vFile:setfs:")) + handle_setfs (own_buf); else return 0; diff --git a/gdb/gdbserver/linux-low.c b/gdb/gdbserver/linux-low.c index 1c4c2d7..42e8a9e 100644 --- a/gdb/gdbserver/linux-low.c +++ b/gdb/gdbserver/linux-low.c @@ -51,6 +51,7 @@ definition of elf_fpregset_t. */ #include #endif +#include "nat/linux-namespaces.h" #ifndef SPUFS_MAGIC #define SPUFS_MAGIC 0x23c9b64e @@ -6434,6 +6435,9 @@ static struct target_ops linux_target_ops = { #endif linux_supports_range_stepping, linux_proc_pid_to_exec_file, + linux_mntns_open_cloexec, + linux_mntns_unlink, + linux_mntns_readlink, }; static void diff --git a/gdb/gdbserver/target.h b/gdb/gdbserver/target.h index 6280c26..7f4a1de 100644 --- a/gdb/gdbserver/target.h +++ b/gdb/gdbserver/target.h @@ -402,6 +402,27 @@ struct target_ops string should be copied into a buffer by the client if the string will not be immediately used, or if it must persist. */ char *(*pid_to_exec_file) (int pid); + + /* Multiple-filesystem-aware open. Like open(2), but operating in + the filesystem as it appears to process PID. Systems where all + processes share a common filesystem should set this to NULL. + If NULL, the caller should fall back to open(2). */ + int (*multifs_open) (int pid, const char *filename, + int flags, mode_t mode); + + /* Multiple-filesystem-aware unlink. Like unlink(2), but operates + in the filesystem as it appears to process PID. Systems where + all processes share a common filesystem should set this to NULL. + If NULL, the caller should fall back to unlink(2). */ + int (*multifs_unlink) (int pid, const char *filename); + + /* Multiple-filesystem-aware readlink. Like readlink(2), but + operating in the filesystem as it appears to process PID. + Systems where all processes share a common filesystem should + set this to NULL. If NULL, the caller should fall back to + readlink(2). */ + ssize_t (*multifs_readlink) (int pid, const char *filename, + char *buf, size_t bufsiz); }; extern struct target_ops *the_target;