Re: [libvirt] [PATCH 11/14] Support for JSON mode monitor

Initial support for the new QEMU monitor protocol using JSON as the data encoding format instead of plain text

--- a/src/Makefile.am +++ b/src/Makefile.am @@ -188,6 +188,8 @@ QEMU_DRIVER_SOURCES = \ qemu/qemu_monitor.c qemu/qemu_monitor.h \ qemu/qemu_monitor_text.c \ qemu/qemu_monitor_text.h \ + qemu/qemu_monitor_json.c \ + qemu/qemu_monitor_json.h \ qemu/qemu_driver.c qemu/qemu_driver.h \ qemu/qemu_bridge_filter.c \

@@ -283,9 +285,14 @@ qemuMonitorIOProcess(qemuMonitorPtr mon) msg = mon->msg; VIR_DEBUG("Process %d", (int)mon->bufferOffset); - len = qemuMonitorTextIOProcess(mon, - mon->buffer, mon->bufferOffset, - msg); + if (mon->json) + len = qemuMonitorJSONIOProcess(mon, + mon->buffer, mon->bufferOffset, + msg); + else + len = qemuMonitorTextIOProcess(mon, + mon->buffer, mon->bufferOffset, + msg);

+#define LINE_ENDING "\r\n" + +static int +qemuMonitorJSONIOProcessLine(qemuMonitorPtr mon ATTRIBUTE_UNUSED, + const char *line, + qemuMonitorMessagePtr msg) +{ + virJSONValuePtr obj = NULL; + int ret = -1; + + VIR_DEBUG("Line [%s]", line); + + if (!(obj = virJSONValueFromString(line))) { + VIR_DEBUG0("Parsing JSON string failed"); + errno = EINVAL; + goto cleanup; + } + + if (obj->type != VIR_JSON_TYPE_OBJECT) { + VIR_DEBUG0("Parsed JSON string isn't an object"); + errno = EINVAL; + } + + if (virJSONValueObjectHasKey(obj, "QMP") == 1) { + VIR_DEBUG0("Got QMP capabilities data"); + ret = 0; + goto cleanup; + } + + if (virJSONValueObjectHasKey(obj, "event") == 1) { + VIR_DEBUG0("Got an event"); + ret = 0; + goto cleanup; + } + + if (msg) { + msg->rxBuffer = strdup(line); + msg->rxLength = strlen(line); + msg->finished = 1; + } else { + VIR_DEBUG("Ignoring unexpected JSON message [%s]", line); + } + + ret = 0; + +cleanup: + virJSONValueFree(obj); + return ret; +}

+int qemuMonitorJSONIOProcess(qemuMonitorPtr mon, + const char *data, + size_t len, + qemuMonitorMessagePtr msg) +{ + int used = 0; + /*VIR_DEBUG("Data %d bytes [%s]", len, data);*/ + + while (used < len) { + char *nl = strstr(data + used, LINE_ENDING); + + if (nl) { + int got = nl - (data + used); + char *line = strndup(data + used, got); + used += got + strlen(LINE_ENDING); + line[got] = '\0'; /* kill \n */ + if (qemuMonitorJSONIOProcessLine(mon, line, msg) < 0) { + VIR_FREE(line); + return -1; + } + + VIR_FREE(line); + } else { + break; + } + }

+ VIR_DEBUG("Total used %d bytes out of %d available in buffer", used, len); + return used; +}

+static virJSONValuePtr +qemuMonitorJSONMakeCommand(const char *cmdname, + ...)

+{ + virJSONValuePtr obj; + virJSONValuePtr jargs = NULL; + va_list args; + char *key; + + va_start(args, cmdname); + + if (!(obj = virJSONValueNewObject())) + goto no_memory; + + if (virJSONValueObjectAppendString(obj, "execute", cmdname) < 0) + goto no_memory; + + if (qemuMonitorJSONCommandAddTimestamp(obj) < 0) + goto error; + + while ((key = va_arg(args, char *)) != NULL) { + int ret; + char type; + + if (strlen(key) < 3) { + qemudReportError(NULL, NULL, NULL, VIR_ERR_INTERNAL_ERROR, + _("argument key '%s' is too short, missing type prefix"), + key); + goto error; + } + + /* Keys look like s:name the first letter is a type code */ + type = key[0]; + key += 2;

+ if (!jargs && + !(jargs = virJSONValueNewObject())) + goto no_memory; + + /* This doesn't supports maps/arrays. This hasn't + * proved to be a problem..... yet :-) */ + switch (type) { + case 's': { + char *val = va_arg(args, char *); + ret = virJSONValueObjectAppendString(jargs, key, val); + } break; + case 'i': { + int val = va_arg(args, int); + ret = virJSONValueObjectAppendNumberInt(jargs, key, val); + } break; + case 'u': { + unsigned int val = va_arg(args, unsigned int); + ret = virJSONValueObjectAppendNumberUint(jargs, key, val); + } break; + case 'I': { + long long val = va_arg(args, long long); + ret = virJSONValueObjectAppendNumberLong(jargs, key, val); + } break; + case 'U': { + unsigned long long val = va_arg(args, unsigned long long); + ret = virJSONValueObjectAppendNumberUlong(jargs, key, val); + } break; + case 'd': { + double val = va_arg(args, double); + ret = virJSONValueObjectAppendNumberDouble(jargs, key, val); + } break; + case 'b': { + int val = va_arg(args, int); + ret = virJSONValueObjectAppendBoolean(jargs, key, val); + } break; + case 'n': { + ret = virJSONValueObjectAppendNull(jargs, key); + } break; + default: + qemudReportError(NULL, NULL, NULL, VIR_ERR_INTERNAL_ERROR, + _("unsupported data type '%c' for arg '%s'"), type, key - 2); + goto error; + } + if (ret < 0) + goto no_memory; + } + + if (jargs && + virJSONValueObjectAppend(obj, "arguments", jargs) < 0) + goto no_memory; + + va_end(args); + + return obj; + +no_memory: + virReportOOMError(NULL); +error: + virJSONValueFree(obj); + virJSONValueFree(jargs); + va_end(args); + return NULL; +}

+{ + int ret; + virJSONValuePtr cmd = qemuMonitorJSONMakeCommand("balloon", + "U:value", (unsigned long long)newmem,

diff --git a/src/qemu/qemu_monitor_json.h b/src/qemu/qemu_monitor_json.h new file mode 100644 index 0000000..62a88c0 --- /dev/null +++ b/src/qemu/qemu_monitor_json.h @@ -0,0 +1,156 @@

diff --git a/tests/qemuxml2argvtest.c b/tests/qemuxml2argvtest.c index 677c5b4..c39cbbc 100644 --- a/tests/qemuxml2argvtest.c +++ b/tests/qemuxml2argvtest.c @@ -60,7 +60,7 @@ static int testCompareXMLToArgvFiles(const char *xml, goto fail; if (qemudBuildCommandLine(NULL, &driver, - vmdef, &monitor_chr, flags, + vmdef, &monitor_chr, 0, flags, &argv, &qenv, NULL, NULL, migrateFrom) < 0) goto fail;