Jon Medhurst | 15ce78d | 2014-04-10 09:02:02 +0100 | [diff] [blame^] | 1 | /** |
| 2 | * Copyright (C) ARM Limited 2013-2014. All rights reserved. |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License version 2 as |
| 6 | * published by the Free Software Foundation. |
| 7 | */ |
| 8 | |
| 9 | #include "UEvent.h" |
| 10 | |
| 11 | #include <linux/netlink.h> |
| 12 | #include <string.h> |
| 13 | #include <sys/socket.h> |
| 14 | #include <unistd.h> |
| 15 | |
| 16 | #include "Logging.h" |
| 17 | |
| 18 | static const char EMPTY[] = ""; |
| 19 | static const char ACTION[] = "ACTION="; |
| 20 | static const char DEVPATH[] = "DEVPATH="; |
| 21 | static const char SUBSYSTEM[] = "SUBSYSTEM="; |
| 22 | |
| 23 | UEvent::UEvent() : mFd(-1) { |
| 24 | } |
| 25 | |
| 26 | UEvent::~UEvent() { |
| 27 | if (mFd >= 0) { |
| 28 | close(mFd); |
| 29 | } |
| 30 | } |
| 31 | |
| 32 | bool UEvent::init() { |
| 33 | mFd = socket(PF_NETLINK, SOCK_RAW, NETLINK_KOBJECT_UEVENT); |
| 34 | if (mFd < 0) { |
| 35 | logg->logMessage("%s(%s:%i): socket failed", __FUNCTION__, __FILE__, __LINE__); |
| 36 | return false; |
| 37 | } |
| 38 | |
| 39 | struct sockaddr_nl sockaddr; |
| 40 | memset(&sockaddr, 0, sizeof(sockaddr)); |
| 41 | sockaddr.nl_family = AF_NETLINK; |
| 42 | sockaddr.nl_groups = 1; // bitmask: (1 << 0) == kernel events, (1 << 1) == udev events |
| 43 | sockaddr.nl_pid = 0; |
| 44 | if (bind(mFd, (struct sockaddr *)&sockaddr, sizeof(sockaddr)) != 0) { |
| 45 | logg->logMessage("%s(%s:%i): bind failed", __FUNCTION__, __FILE__, __LINE__); |
| 46 | return false; |
| 47 | } |
| 48 | |
| 49 | return true; |
| 50 | } |
| 51 | |
| 52 | bool UEvent::read(UEventResult *const result) { |
| 53 | ssize_t bytes = recv(mFd, result->mBuf, sizeof(result->mBuf), 0); |
| 54 | if (bytes <= 0) { |
| 55 | logg->logMessage("%s(%s:%i): recv failed", __FUNCTION__, __FILE__, __LINE__); |
| 56 | return false; |
| 57 | } |
| 58 | |
| 59 | result->mAction = EMPTY; |
| 60 | result->mDevPath = EMPTY; |
| 61 | result->mSubsystem = EMPTY; |
| 62 | |
| 63 | for (int pos = 0; pos < bytes; pos += strlen(result->mBuf + pos) + 1) { |
| 64 | char *const str = result->mBuf + pos; |
| 65 | if (strncmp(str, ACTION, sizeof(ACTION) - 1) == 0) { |
| 66 | result->mAction = str + sizeof(ACTION) - 1; |
| 67 | } else if (strncmp(str, DEVPATH, sizeof(DEVPATH) - 1) == 0) { |
| 68 | result->mDevPath = str + sizeof(DEVPATH) - 1; |
| 69 | } else if (strncmp(str, SUBSYSTEM, sizeof(SUBSYSTEM) - 1) == 0) { |
| 70 | result->mSubsystem = str + sizeof(SUBSYSTEM) - 1; |
| 71 | } |
| 72 | } |
| 73 | |
| 74 | return true; |
| 75 | } |