Home | History | Annotate | Download | only in include 
      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 
     17 #ifndef ANDROID_INCLUDE_HARDWARE_QEMUD_H
     18 #define ANDROID_INCLUDE_HARDWARE_QEMUD_H
     19 
     20 #include <cutils/sockets.h>
     21 #include "qemu_pipe.h"
     22 
     23 /* the following is helper code that is used by the QEMU-specific
     24  * hardware HAL modules to communicate with the emulator program
     25  * through the 'qemud' multiplexing daemon, or through the qemud
     26  * pipe.
     27  *
     28  * see the documentation comments for details in
     29  * development/emulator/qemud/qemud.c
     30  *
     31  * all definitions here are built into the HAL module to avoid
     32  * having to write a tiny shared library for this.
     33  */
     34 
     35 /* we expect the D macro to be defined to a function macro
     36  * that sends its formatted string argument(s) to the log.
     37  * If not, ignore the traces.
     38  */
     39 #ifndef D
     40 #  define  D(...)   do{}while(0)
     41 #endif
     42 
     43 
     44 static __inline__ int
     45 qemud_channel_open(const char*  name)
     46 {
     47     int  fd;
     48     int  namelen = strlen(name);
     49     char answer[2];
     50     char pipe_name[256];
     51 
     52     /* First, try to connect to the pipe. */
     53     snprintf(pipe_name, sizeof(pipe_name), "qemud:%s", name);
     54     fd = qemu_pipe_open(pipe_name);
     55     D("%s: pipe name %s (name %s) fd %d", __FUNCTION__, pipe_name, name, fd);
     56     if (fd < 0) {
     57         D("QEMUD pipe is not available for %s: %s", name, strerror(errno));
     58         /* If pipe is not available, connect to qemud control socket */
     59         fd = socket_local_client( "qemud",
     60                                   ANDROID_SOCKET_NAMESPACE_RESERVED,
     61                                   SOCK_STREAM );
     62         if (fd < 0) {
     63             D("no qemud control socket: %s", strerror(errno));
     64             return -1;
     65         }
     66 
     67         /* send service name to connect */
     68         if (!WriteFully(fd, name, namelen)) {
     69             D("can't send service name to qemud: %s",
     70                strerror(errno));
     71             close(fd);
     72             return -1;
     73         }
     74 
     75         /* read answer from daemon */
     76         if (!ReadFully(fd, answer, 2) ||
     77             answer[0] != 'O' || answer[1] != 'K') {
     78             D("cant' connect to %s service through qemud", name);
     79             close(fd);
     80             return -1;
     81         }
     82     }
     83     return fd;
     84 }
     85 
     86 static __inline__ int
     87 qemud_channel_send(int  fd, const void*  msg, int  msglen)
     88 {
     89     char  header[5];
     90 
     91     if (msglen < 0)
     92         msglen = strlen((const char*)msg);
     93 
     94     if (msglen == 0)
     95         return 0;
     96 
     97     snprintf(header, sizeof header, "%04x", msglen);
     98     if (!WriteFully(fd, header, 4)) {
     99         D("can't write qemud frame header: %s", strerror(errno));
    100         return -1;
    101     }
    102 
    103     if (!WriteFully(fd, msg, msglen)) {
    104         D("can4t write qemud frame payload: %s", strerror(errno));
    105         return -1;
    106     }
    107     return 0;
    108 }
    109 
    110 static __inline__ int
    111 qemud_channel_recv(int  fd, void*  msg, int  msgsize)
    112 {
    113     char  header[5];
    114     int   size;
    115 
    116     if (!ReadFully(fd, header, 4)) {
    117         D("can't read qemud frame header: %s", strerror(errno));
    118         return -1;
    119     }
    120     header[4] = 0;
    121     if (sscanf(header, "%04x", &size) != 1) {
    122         D("malformed qemud frame header: '%.*s'", 4, header);
    123         return -1;
    124     }
    125     if (size > msgsize)
    126         return -1;
    127 
    128     if (!ReadFully(fd, msg, size)) {
    129         D("can't read qemud frame payload: %s", strerror(errno));
    130         return -1;
    131     }
    132     return size;
    133 }
    134 
    135 #endif /* ANDROID_INCLUDE_HARDWARE_QEMUD_H */
    136