1// Copyright (c) 2010 Google Inc.
2// All rights reserved.
3//
4// Redistribution and use in source and binary forms, with or without
5// modification, are permitted provided that the following conditions are
6// met:
7//
8// * Redistributions of source code must retain the above copyright
9// notice, this list of conditions and the following disclaimer.
10// * Redistributions in binary form must reproduce the above
11// copyright notice, this list of conditions and the following disclaimer
12// in the documentation and/or other materials provided with the
13// distribution.
14// * Neither the name of Google Inc. nor the names of its
15// contributors may be used to endorse or promote products derived from
16// this software without specific prior written permission.
17//
18// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29
30#include "client/linux/crash_generation/crash_generation_client.h"
31
32#include <stdio.h>
33#include <sys/socket.h>
34#include <sys/types.h>
35
36#include <algorithm>
37
38#include "common/linux/eintr_wrapper.h"
39#include "common/linux/ignore_ret.h"
40#include "third_party/lss/linux_syscall_support.h"
41
42namespace google_breakpad {
43
44namespace {
45
46class CrashGenerationClientImpl : public CrashGenerationClient {
47 public:
48 explicit CrashGenerationClientImpl(int server_fd) : server_fd_(server_fd) {}
49 virtual ~CrashGenerationClientImpl() {}
50
51 virtual bool RequestDump(const void* blob, size_t blob_size) {
52 int fds[2];
53 if (sys_pipe(fds) < 0)
54 return false;
55 static const unsigned kControlMsgSize = CMSG_SPACE(sizeof(int));
56
57 struct kernel_iovec iov;
58 iov.iov_base = const_cast<void*>(blob);
59 iov.iov_len = blob_size;
60
61 struct kernel_msghdr msg = { 0 };
62 msg.msg_iov = &iov;
63 msg.msg_iovlen = 1;
64 char cmsg[kControlMsgSize] = "";
65 msg.msg_control = cmsg;
66 msg.msg_controllen = sizeof(cmsg);
67
68 struct cmsghdr* hdr = CMSG_FIRSTHDR(&msg);
69 hdr->cmsg_level = SOL_SOCKET;
70 hdr->cmsg_type = SCM_RIGHTS;
71 hdr->cmsg_len = CMSG_LEN(sizeof(int));
72 int* p = reinterpret_cast<int*>(CMSG_DATA(hdr));
73 *p = fds[1];
74
75 ssize_t ret = HANDLE_EINTR(sys_sendmsg(server_fd_, &msg, 0));
76 sys_close(fds[1]);
77 if (ret < 0) {
78 sys_close(fds[0]);
79 return false;
80 }
81
82 // Wait for an ACK from the server.
83 char b;
84 IGNORE_RET(HANDLE_EINTR(sys_read(fds[0], &b, 1)));
85 sys_close(fds[0]);
86
87 return true;
88 }
89
90 private:
91 int server_fd_;
92
93 DISALLOW_COPY_AND_ASSIGN(CrashGenerationClientImpl);
94};
95
96} // namespace
97
98// static
99CrashGenerationClient* CrashGenerationClient::TryCreate(int server_fd) {
100 if (server_fd < 0)
101 return NULL;
102 return new CrashGenerationClientImpl(server_fd);
103}
104
105} // namespace google_breakpad
106