FrameworkListener.cpp revision 696f267ff5a1e6227c2f5784dae60c190e0228b8 
1/*
2 * Copyright (C) 2008 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16#include <errno.h>
17#include <string.h>
18#include <stdlib.h>
19
20#define LOG_TAG "FrameworkListener"
21
22#include <cutils/log.h>
23
24#include <sysutils/FrameworkListener.h>
25#include <sysutils/FrameworkCommand.h>
26#include <sysutils/SocketClient.h>
27
28static const int CMD_BUF_SIZE = 1024;
29
30#define UNUSED __attribute__((unused))
31
32FrameworkListener::FrameworkListener(const char *socketName, bool withSeq) :
33                            SocketListener(socketName, true, withSeq) {
34    init(socketName, withSeq);
35}
36
37FrameworkListener::FrameworkListener(const char *socketName) :
38                            SocketListener(socketName, true, false) {
39    init(socketName, false);
40}
41
42void FrameworkListener::init(const char *socketName UNUSED, bool withSeq) {
43    mCommands = new FrameworkCommandCollection();
44    errorRate = 0;
45    mCommandCount = 0;
46    mWithSeq = withSeq;
47}
48
49bool FrameworkListener::onDataAvailable(SocketClient *c) {
50    char buffer[CMD_BUF_SIZE];
51    int len;
52
53    len = TEMP_FAILURE_RETRY(read(c->getSocket(), buffer, sizeof(buffer)));
54    if (len < 0) {
55        SLOGE("read() failed (%s)", strerror(errno));
56        return false;
57    } else if (!len)
58        return false;
59   if(buffer[len-1] != '\0')
60        SLOGW("String is not zero-terminated");
61
62    int offset = 0;
63    int i;
64
65    for (i = 0; i < len; i++) {
66        if (buffer[i] == '\0') {
67            /* IMPORTANT: dispatchCommand() expects a zero-terminated string */
68            dispatchCommand(c, buffer + offset);
69            offset = i + 1;
70        }
71    }
72
73    return true;
74}
75
76void FrameworkListener::registerCmd(FrameworkCommand *cmd) {
77    mCommands->push_back(cmd);
78}
79
80void FrameworkListener::dispatchCommand(SocketClient *cli, char *data) {
81    FrameworkCommandCollection::iterator i;
82    int argc = 0;
83    char *argv[FrameworkListener::CMD_ARGS_MAX];
84    char tmp[CMD_BUF_SIZE];
85    char *p = data;
86    char *q = tmp;
87    char *qlimit = tmp + sizeof(tmp) - 1;
88    bool esc = false;
89    bool quote = false;
90    int k;
91    bool haveCmdNum = !mWithSeq;
92
93    memset(argv, 0, sizeof(argv));
94    memset(tmp, 0, sizeof(tmp));
95    while(*p) {
96        if (*p == '\\') {
97            if (esc) {
98                if (q >= qlimit)
99                    goto overflow;
100                *q++ = '\\';
101                esc = false;
102            } else
103                esc = true;
104            p++;
105            continue;
106        } else if (esc) {
107            if (*p == '"') {
108                if (q >= qlimit)
109                    goto overflow;
110                *q++ = '"';
111            } else if (*p == '\\') {
112                if (q >= qlimit)
113                    goto overflow;
114                *q++ = '\\';
115            } else {
116                cli->sendMsg(500, "Unsupported escape sequence", false);
117                goto out;
118            }
119            p++;
120            esc = false;
121            continue;
122        }
123
124        if (*p == '"') {
125            if (quote)
126                quote = false;
127            else
128                quote = true;
129            p++;
130            continue;
131        }
132
133        if (q >= qlimit)
134            goto overflow;
135        *q = *p++;
136        if (!quote && *q == ' ') {
137            *q = '\0';
138            if (!haveCmdNum) {
139                char *endptr;
140                int cmdNum = (int)strtol(tmp, &endptr, 0);
141                if (endptr == NULL || *endptr != '\0') {
142                    cli->sendMsg(500, "Invalid sequence number", false);
143                    goto out;
144                }
145                cli->setCmdNum(cmdNum);
146                haveCmdNum = true;
147            } else {
148                if (argc >= CMD_ARGS_MAX)
149                    goto overflow;
150                argv[argc++] = strdup(tmp);
151            }
152            memset(tmp, 0, sizeof(tmp));
153            q = tmp;
154            continue;
155        }
156        q++;
157    }
158
159    *q = '\0';
160    if (argc >= CMD_ARGS_MAX)
161        goto overflow;
162    argv[argc++] = strdup(tmp);
163#if 0
164    for (k = 0; k < argc; k++) {
165        SLOGD("arg[%d] = '%s'", k, argv[k]);
166    }
167#endif
168
169    if (quote) {
170        cli->sendMsg(500, "Unclosed quotes error", false);
171        goto out;
172    }
173
174    if (errorRate && (++mCommandCount % errorRate == 0)) {
175        /* ignore this command - let the timeout handler handle it */
176        SLOGE("Faking a timeout");
177        goto out;
178    }
179
180    for (i = mCommands->begin(); i != mCommands->end(); ++i) {
181        FrameworkCommand *c = *i;
182
183        if (!strcmp(argv[0], c->getCommand())) {
184            if (c->runCommand(cli, argc, argv)) {
185                SLOGW("Handler '%s' error (%s)", c->getCommand(), strerror(errno));
186            }
187            goto out;
188        }
189    }
190    cli->sendMsg(500, "Command not recognized", false);
191out:
192    int j;
193    for (j = 0; j < argc; j++)
194        free(argv[j]);
195    return;
196
197overflow:
198    LOG_EVENT_INT(78001, cli->getUid());
199    cli->sendMsg(500, "Command too long", false);
200    goto out;
201}
202