1 /* 2 * QTest 3 * 4 * Copyright IBM, Corp. 2012 5 * Copyright Red Hat, Inc. 2012 6 * Copyright SUSE LINUX Products GmbH 2013 7 * 8 * Authors: 9 * Anthony Liguori <aliguori@us.ibm.com> 10 * Paolo Bonzini <pbonzini@redhat.com> 11 * Andreas Färber <afaerber@suse.de> 12 * 13 * This work is licensed under the terms of the GNU GPL, version 2 or later. 14 * See the COPYING file in the top-level directory. 15 */ 16 17 #include "qemu/osdep.h" 18 19 #include "libqmp.h" 20 21 #include "qapi/error.h" 22 #include "qapi/qmp/json-parser.h" 23 #include "qapi/qmp/qjson.h" 24 25 #define SOCKET_MAX_FDS 16 26 27 typedef struct { 28 JSONMessageParser parser; 29 QDict *response; 30 } QMPResponseParser; 31 32 static void socket_send(int fd, const char *buf, size_t size) 33 { 34 size_t res = qemu_write_full(fd, buf, size); 35 36 assert(res == size); 37 } 38 39 static void qmp_response(void *opaque, QObject *obj, Error *err) 40 { 41 QMPResponseParser *qmp = opaque; 42 43 assert(!obj != !err); 44 45 if (err) { 46 error_prepend(&err, "QMP JSON response parsing failed: "); 47 error_report_err(err); 48 abort(); 49 } 50 51 g_assert(!qmp->response); 52 qmp->response = qobject_to(QDict, obj); 53 g_assert(qmp->response); 54 } 55 56 QDict *qmp_fd_receive(int fd) 57 { 58 QMPResponseParser qmp; 59 bool log = getenv("QTEST_LOG") != NULL; 60 61 qmp.response = NULL; 62 json_message_parser_init(&qmp.parser, qmp_response, &qmp, NULL); 63 while (!qmp.response) { 64 ssize_t len; 65 char c; 66 67 len = read(fd, &c, 1); 68 if (len == -1 && errno == EINTR) { 69 continue; 70 } 71 72 if (len == -1 || len == 0) { 73 fprintf(stderr, "Broken pipe\n"); 74 abort(); 75 } 76 77 if (log) { 78 g_assert(write(2, &c, 1) == 1); 79 } 80 json_message_parser_feed(&qmp.parser, &c, 1); 81 } 82 if (log) { 83 g_assert(write(2, "\n", 1) == 1); 84 } 85 json_message_parser_destroy(&qmp.parser); 86 87 return qmp.response; 88 } 89 90 /* Sends a message and file descriptors to the socket. 91 * It's needed for qmp-commands like getfd/add-fd */ 92 static void socket_send_fds(int socket_fd, int *fds, size_t fds_num, 93 const char *buf, size_t buf_size) 94 { 95 ssize_t ret; 96 struct msghdr msg = { 0 }; 97 char control[CMSG_SPACE(sizeof(int) * SOCKET_MAX_FDS)] = { 0 }; 98 size_t fdsize = sizeof(int) * fds_num; 99 struct cmsghdr *cmsg; 100 struct iovec iov = { .iov_base = (char *)buf, .iov_len = buf_size }; 101 102 msg.msg_iov = &iov; 103 msg.msg_iovlen = 1; 104 105 if (fds && fds_num > 0) { 106 g_assert_cmpuint(fds_num, <, SOCKET_MAX_FDS); 107 108 msg.msg_control = control; 109 msg.msg_controllen = CMSG_SPACE(fdsize); 110 111 cmsg = CMSG_FIRSTHDR(&msg); 112 cmsg->cmsg_len = CMSG_LEN(fdsize); 113 cmsg->cmsg_level = SOL_SOCKET; 114 cmsg->cmsg_type = SCM_RIGHTS; 115 memcpy(CMSG_DATA(cmsg), fds, fdsize); 116 } 117 118 do { 119 ret = sendmsg(socket_fd, &msg, 0); 120 } while (ret < 0 && errno == EINTR); 121 g_assert_cmpint(ret, >, 0); 122 } 123 124 /** 125 * Allow users to send a message without waiting for the reply, 126 * in the case that they choose to discard all replies up until 127 * a particular EVENT is received. 128 */ 129 void qmp_fd_vsend_fds(int fd, int *fds, size_t fds_num, 130 const char *fmt, va_list ap) 131 { 132 QObject *qobj; 133 134 /* Going through qobject ensures we escape strings properly */ 135 qobj = qobject_from_vjsonf_nofail(fmt, ap); 136 137 /* No need to send anything for an empty QObject. */ 138 if (qobj) { 139 int log = getenv("QTEST_LOG") != NULL; 140 GString *str = qobject_to_json(qobj); 141 142 /* 143 * BUG: QMP doesn't react to input until it sees a newline, an 144 * object, or an array. Work-around: give it a newline. 145 */ 146 g_string_append_c(str, '\n'); 147 148 if (log) { 149 fprintf(stderr, "%s", str->str); 150 } 151 /* Send QMP request */ 152 if (fds && fds_num > 0) { 153 socket_send_fds(fd, fds, fds_num, str->str, str->len); 154 } else { 155 socket_send(fd, str->str, str->len); 156 } 157 158 g_string_free(str, true); 159 qobject_unref(qobj); 160 } 161 } 162 163 void qmp_fd_vsend(int fd, const char *fmt, va_list ap) 164 { 165 qmp_fd_vsend_fds(fd, NULL, 0, fmt, ap); 166 } 167 168 169 QDict *qmp_fdv(int fd, const char *fmt, va_list ap) 170 { 171 qmp_fd_vsend_fds(fd, NULL, 0, fmt, ap); 172 173 return qmp_fd_receive(fd); 174 } 175 176 QDict *qmp_fd(int fd, const char *fmt, ...) 177 { 178 va_list ap; 179 QDict *response; 180 181 va_start(ap, fmt); 182 response = qmp_fdv(fd, fmt, ap); 183 va_end(ap); 184 return response; 185 } 186 187 void qmp_fd_send(int fd, const char *fmt, ...) 188 { 189 va_list ap; 190 191 va_start(ap, fmt); 192 qmp_fd_vsend(fd, fmt, ap); 193 va_end(ap); 194 } 195 196 void qmp_fd_vsend_raw(int fd, const char *fmt, va_list ap) 197 { 198 bool log = getenv("QTEST_LOG") != NULL; 199 char *str = g_strdup_vprintf(fmt, ap); 200 201 if (log) { 202 fprintf(stderr, "%s", str); 203 } 204 socket_send(fd, str, strlen(str)); 205 g_free(str); 206 } 207 208 void qmp_fd_send_raw(int fd, const char *fmt, ...) 209 { 210 va_list ap; 211 212 va_start(ap, fmt); 213 qmp_fd_vsend_raw(fd, fmt, ap); 214 va_end(ap); 215 } 216 217 bool qmp_rsp_is_err(QDict *rsp) 218 { 219 QDict *error = qdict_get_qdict(rsp, "error"); 220 qobject_unref(rsp); 221 return !!error; 222 } 223 224 void qmp_expect_error_and_unref(QDict *rsp, const char *class) 225 { 226 QDict *error = qdict_get_qdict(rsp, "error"); 227 228 g_assert_cmpstr(qdict_get_try_str(error, "class"), ==, class); 229 g_assert_nonnull(qdict_get_try_str(error, "desc")); 230 g_assert(!qdict_haskey(rsp, "return")); 231 232 qobject_unref(rsp); 233 } 234