| 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(...) ((void)0) |
| 41 | #endif |
| 42 | |
| 43 | static __inline__ int |
| 44 | qemud_fd_write(int fd, const void* buff, int len) |
| 45 | { |
| 46 | int len2; |
| 47 | do { |
| 48 | len2 = write(fd, buff, len); |
| 49 | } while (len2 < 0 && errno == EINTR); |
| 50 | return len2; |
| 51 | } |
| 52 | |
| 53 | static __inline__ int |
| 54 | qemud_fd_read(int fd, void* buff, int len) |
| 55 | { |
| 56 | int len2; |
| 57 | do { |
| 58 | len2 = read(fd, buff, len); |
| 59 | } while (len2 < 0 && errno == EINTR); |
| 60 | return len2; |
| 61 | } |
| 62 | |
| 63 | static __inline__ int |
| 64 | qemud_channel_open(const char* name) |
| 65 | { |
| 66 | int fd; |
| 67 | int namelen = strlen(name); |
| 68 | char answer[2]; |
| 69 | char pipe_name[256]; |
| 70 | |
| 71 | /* First, try to connect to the pipe. */ |
| 72 | snprintf(pipe_name, sizeof(pipe_name), "qemud:%s", name); |
| 73 | fd = qemu_pipe_open(pipe_name); |
| 74 | if (fd < 0) { |
| 75 | D("QEMUD pipe is not available for %s: %s", name, strerror(errno)); |
| 76 | /* If pipe is not available, connect to qemud control socket */ |
| 77 | fd = socket_local_client( "qemud", |
| 78 | ANDROID_SOCKET_NAMESPACE_RESERVED, |
| 79 | SOCK_STREAM ); |
| 80 | if (fd < 0) { |
| 81 | D("no qemud control socket: %s", strerror(errno)); |
| 82 | return -1; |
| 83 | } |
| 84 | |
| 85 | /* send service name to connect */ |
| 86 | if (qemud_fd_write(fd, name, namelen) != namelen) { |
| 87 | D("can't send service name to qemud: %s", |
| 88 | strerror(errno)); |
| 89 | close(fd); |
| 90 | return -1; |
| 91 | } |
| 92 | |
| 93 | /* read answer from daemon */ |
| 94 | if (qemud_fd_read(fd, answer, 2) != 2 || |
| 95 | answer[0] != 'O' || answer[1] != 'K') { |
| 96 | D("cant' connect to %s service through qemud", name); |
| 97 | close(fd); |
| 98 | return -1; |
| 99 | } |
| 100 | } |
| 101 | return fd; |
| 102 | } |
| 103 | |
| 104 | static __inline__ int |
| 105 | qemud_channel_send(int fd, const void* msg, int msglen) |
| 106 | { |
| 107 | char header[5]; |
| 108 | |
| 109 | if (msglen < 0) |
| 110 | msglen = strlen((const char*)msg); |
| 111 | |
| 112 | if (msglen == 0) |
| 113 | return 0; |
| 114 | |
| 115 | snprintf(header, sizeof header, "%04x", msglen); |
| 116 | if (qemud_fd_write(fd, header, 4) != 4) { |
| 117 | D("can't write qemud frame header: %s", strerror(errno)); |
| 118 | return -1; |
| 119 | } |
| 120 | |
| 121 | if (qemud_fd_write(fd, msg, msglen) != msglen) { |
| 122 | D("can4t write qemud frame payload: %s", strerror(errno)); |
| 123 | return -1; |
| 124 | } |
| 125 | return 0; |
| 126 | } |
| 127 | |
| 128 | static __inline__ int |
| 129 | qemud_channel_recv(int fd, void* msg, int msgsize) |
| 130 | { |
| 131 | char header[5]; |
| 132 | int size, avail; |
| 133 | |
| 134 | if (qemud_fd_read(fd, header, 4) != 4) { |
| 135 | D("can't read qemud frame header: %s", strerror(errno)); |
| 136 | return -1; |
| 137 | } |
| 138 | header[4] = 0; |
| 139 | if (sscanf(header, "%04x", &size) != 1) { |
| 140 | D("malformed qemud frame header: '%.*s'", 4, header); |
| 141 | return -1; |
| 142 | } |
| 143 | if (size > msgsize) |
| 144 | return -1; |
| 145 | |
| 146 | if (qemud_fd_read(fd, msg, size) != size) { |
| 147 | D("can't read qemud frame payload: %s", strerror(errno)); |
| 148 | return -1; |
| 149 | } |
| 150 | return size; |
| 151 | } |
| 152 | |
| 153 | #endif /* ANDROID_INCLUDE_HARDWARE_QEMUD_H */ |