Android WIFI模块解析

Android中的AP扫描结果，通过WifiNative的JNI调用，实际调用wpa_supplicant的相应命令，并返回字符串给JNI方法，下面是对该字符串的解析函数：

private static final Pattern scanResultPattern = Pattern.compile("\t+");
/**
     * Parse the scan result line passed to us by wpa_supplicant (helper).
     * @param line the line to parse
     * @return the {@link ScanResult} object
     */
    private ScanResult parseScanResult(String line) {
        ScanResult scanResult = null;
        if (line != null) {
            /*
             * Cache implementation (LinkedHashMap) is not synchronized, thus,
             * must synchronized here!
             */
            synchronized (mScanResultCache) {
                String[] result = scanResultPattern.split(line);
                if (3 <= result.length && result.length <= 5) {
                    String bssid = result[0];
                    // bssid | frequency | level | flags | ssid
                    int frequency;
                    int level;
                    try {
                        frequency = Integer.parseInt(result[1]);
                        level = Integer.parseInt(result[2]);
                        /* some implementations avoid negative values by adding 256
                         * so we need to adjust for that here.
                         */
                        if (level > 0) level -= 256;
                    } catch (NumberFormatException e) {
                        frequency = 0;
                        level = 0;
                    }

                    /*
                     * The formatting of the results returned by
                     * wpa_supplicant is intended to make the fields
                     * line up nicely when printed,
                     * not to make them easy to parse. So we have to
                     * apply some heuristics to figure out which field
                     * is the SSID and which field is the flags.
                     */
                    String ssid;
                    String flags;
                    if (result.length == 4) {
                        if (result[3].charAt(0) == '[') {
                            flags = result[3];
                            ssid = "";
                        } else {
                            flags = "";
                            ssid = result[3];
                        }
                    } else if (result.length == 5) {
                        flags = result[3];
                        ssid = result[4];
                    } else {
                        // Here, we must have 3 fields: no flags and ssid
                        // set
                        flags = "";
                        ssid = "";
                    }

                    // bssid + ssid is the hash key
                    String key = bssid + ssid;
                    scanResult = mScanResultCache.get(key);
                    if (scanResult != null) {
                        scanResult.level = level;
                        scanResult.SSID = ssid;
                        scanResult.capabilities = flags;
                        scanResult.frequency = frequency;
                    } else {
                        // Do not add scan results that have no SSID set
                        if (0 < ssid.trim().length()) {
                            scanResult =
                                new ScanResult(
                                    ssid, bssid, flags, level, frequency);
                            mScanResultCache.put(key, scanResult);
                        }
                    }
                } else {
                    Slog.w(TAG, "Misformatted scan result text with " +
                          result.length + " fields: " + line);
                }
            }
        }

        return scanResult;
    }

WIFI添加一个网络配置，返回生成的网络ID

/**
     * see {@link android.net.wifi.WifiManager#addOrUpdateNetwork(WifiConfiguration)}
     * @return the supplicant-assigned identifier for the new or updated
     * network if the operation succeeds, or {@code -1} if it fails
     */
    public int addOrUpdateNetwork(WifiConfiguration config) {
        enforceChangePermission();

        /*
         * If the supplied networkId is -1, we create a new empty
         * network configuration. Otherwise, the networkId should
         * refer to an existing configuration.
         */
        int netId = config.networkId;
        boolean newNetwork = netId == -1;
        boolean doReconfig = false;
        // networkId of -1 means we want to create a new network
        synchronized (mWifiStateTracker) {
            if (newNetwork) {
                netId = mWifiStateTracker.addNetwork();
                if (netId < 0) {
                    if (DBG) {
                        Slog.d(TAG, "Failed to add a network!");
                    }
                    return -1;
                }
                doReconfig = true;
            }
            mNeedReconfig = mNeedReconfig || doReconfig;
        }

        setVariables: {
            /*
             * Note that if a networkId for a non-existent network
             * was supplied, then the first setNetworkVariable()
             * will fail, so we don't bother to make a separate check
             * for the validity of the ID up front.
             */
            if (config.SSID != null &&
                    !mWifiStateTracker.setNetworkVariable(
                        netId,
                        WifiConfiguration.ssidVarName,
                        config.SSID)) {
                if (DBG) {
                    Slog.d(TAG, "failed to set SSID: "+config.SSID);
                }
                break setVariables;
            }

            if (config.BSSID != null &&
                    !mWifiStateTracker.setNetworkVariable(
                        netId,
                        WifiConfiguration.bssidVarName,
                        config.BSSID)) {
                if (DBG) {
                    Slog.d(TAG, "failed to set BSSID: "+config.BSSID);
                }
                break setVariables;
            }

            String allowedKeyManagementString =
                makeString(config.allowedKeyManagement, WifiConfiguration.KeyMgmt.strings);
            if (config.allowedKeyManagement.cardinality() != 0 &&
                    !mWifiStateTracker.setNetworkVariable(
                        netId,
                        WifiConfiguration.KeyMgmt.varName,
                        allowedKeyManagementString)) {
                if (DBG) {
                    Slog.d(TAG, "failed to set key_mgmt: "+
                            allowedKeyManagementString);
                }
                break setVariables;
            }

            String allowedProtocolsString =
                makeString(config.allowedProtocols, WifiConfiguration.Protocol.strings);
            if (config.allowedProtocols.cardinality() != 0 &&
                    !mWifiStateTracker.setNetworkVariable(
                        netId,
                        WifiConfiguration.Protocol.varName,
                        allowedProtocolsString)) {
                if (DBG) {
                    Slog.d(TAG, "failed to set proto: "+
                            allowedProtocolsString);
                }
                break setVariables;
            }

            String allowedAuthAlgorithmsString =
                makeString(config.allowedAuthAlgorithms, WifiConfiguration.AuthAlgorithm.strings);
            if (config.allowedAuthAlgorithms.cardinality() != 0 &&
                    !mWifiStateTracker.setNetworkVariable(
                        netId,
                        WifiConfiguration.AuthAlgorithm.varName,
                        allowedAuthAlgorithmsString)) {
                if (DBG) {
                    Slog.d(TAG, "failed to set auth_alg: "+
                            allowedAuthAlgorithmsString);
                }
                break setVariables;
            }

            String allowedPairwiseCiphersString =
                makeString(config.allowedPairwiseCiphers, WifiConfiguration.PairwiseCipher.strings);
            if (config.allowedPairwiseCiphers.cardinality() != 0 &&
                    !mWifiStateTracker.setNetworkVariable(
                        netId,
                        WifiConfiguration.PairwiseCipher.varName,
                        allowedPairwiseCiphersString)) {
                if (DBG) {
                    Slog.d(TAG, "failed to set pairwise: "+
                            allowedPairwiseCiphersString);
                }
                break setVariables;
            }

            String allowedGroupCiphersString =
                makeString(config.allowedGroupCiphers, WifiConfiguration.GroupCipher.strings);
            if (config.allowedGroupCiphers.cardinality() != 0 &&
                    !mWifiStateTracker.setNetworkVariable(
                        netId,
                        WifiConfiguration.GroupCipher.varName,
                        allowedGroupCiphersString)) {
                if (DBG) {
                    Slog.d(TAG, "failed to set group: "+
                            allowedGroupCiphersString);
                }
                break setVariables;
            }

            // Prevent client screw-up by passing in a WifiConfiguration we gave it
            // by preventing "*" as a key.
            if (config.preSharedKey != null && !config.preSharedKey.equals("*") &&
                    !mWifiStateTracker.setNetworkVariable(
                        netId,
                        WifiConfiguration.pskVarName,
                        config.preSharedKey)) {
                if (DBG) {
                    Slog.d(TAG, "failed to set psk: "+config.preSharedKey);
                }
                break setVariables;
            }

            boolean hasSetKey = false;
            if (config.wepKeys != null) {
                for (int i = 0; i < config.wepKeys.length; i++) {
                    // Prevent client screw-up by passing in a WifiConfiguration we gave it
                    // by preventing "*" as a key.
                    if (config.wepKeys[i] != null && !config.wepKeys[i].equals("*")) {
                        if (!mWifiStateTracker.setNetworkVariable(
                                    netId,
                                    WifiConfiguration.wepKeyVarNames[i],
                                    config.wepKeys[i])) {
                            if (DBG) {
                                Slog.d(TAG,
                                        "failed to set wep_key"+i+": " +
                                        config.wepKeys[i]);
                            }
                            break setVariables;
                        }
                        hasSetKey = true;
                    }
                }
            }

            if (hasSetKey) {
                if (!mWifiStateTracker.setNetworkVariable(
                            netId,
                            WifiConfiguration.wepTxKeyIdxVarName,
                            Integer.toString(config.wepTxKeyIndex))) {
                    if (DBG) {
                        Slog.d(TAG,
                                "failed to set wep_tx_keyidx: "+
                                config.wepTxKeyIndex);
                    }
                    break setVariables;
                }
            }

            if (!mWifiStateTracker.setNetworkVariable(
                        netId,
                        WifiConfiguration.priorityVarName,
                        Integer.toString(config.priority))) {
                if (DBG) {
                    Slog.d(TAG, config.SSID + ": failed to set priority: "
                            +config.priority);
                }
                break setVariables;
            }

            if (config.hiddenSSID && !mWifiStateTracker.setNetworkVariable(
                        netId,
                        WifiConfiguration.hiddenSSIDVarName,
                        Integer.toString(config.hiddenSSID ? 1 : 0))) {
                if (DBG) {
                    Slog.d(TAG, config.SSID + ": failed to set hiddenSSID: "+
                            config.hiddenSSID);
                }
                break setVariables;
            }

            for (WifiConfiguration.EnterpriseField field
                    : config.enterpriseFields) {
                String varName = field.varName();
                String value = field.value();
                if (value != null) {
                    if (field != config.eap) {
                        value = (value.length() == 0) ? "NULL" : convertToQuotedString(value);
                    }
                    if (!mWifiStateTracker.setNetworkVariable(
                                netId,
                                varName,
                                value)) {
                        if (DBG) {
                            Slog.d(TAG, config.SSID + ": failed to set " + varName +
                                    ": " + value);
                        }
                        break setVariables;
                    }
                }
            }
            return netId;
        }

认证类型管理类：

/**
     * Recognized key management schemes.
     */
    public static class KeyMgmt {
        private KeyMgmt() { }

        /** WPA is not used; plaintext or static WEP could be used. */
        public static final int NONE = 0;
        /** WPA pre-shared key (requires {@code preSharedKey} to be specified). */
        public static final int WPA_PSK = 1;
        /** WPA using EAP authentication. Generally used with an external authentication server. */
        public static final int WPA_EAP = 2;
        /** IEEE 802.1X using EAP authentication and (optionally) dynamically
         * generated WEP keys. */
        public static final int IEEE8021X = 3;

        public static final String varName = "key_mgmt";

        public static final String[] strings = { "NONE", "WPA_PSK", "WPA_EAP", "IEEE8021X" };
    }