@@ -138,7 +138,7 @@ obj-y += qemu-char.o aio.o savevm.o
obj-y += msmouse.o ps2.o
obj-y += qdev.o qdev-properties.o
obj-y += qint.o qstring.o qdict.o qlist.o qfloat.o qbool.o json-lexer.o
-obj-y += json-streamer.o json-parser.o qjson.o
+obj-y += json-streamer.o json-parser.o qjson.o qerror.o
obj-y += qemu-config.o
obj-$(CONFIG_BRLAPI) += baum.o
new file mode 100644
@@ -0,0 +1,283 @@
+/*
+ * QError: QEMU Error data-type.
+ *
+ * Copyright (C) 2009 Red Hat Inc.
+ *
+ * Authors:
+ * Luiz Capitulino <lcapitulino@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ */
+#include "qjson.h"
+#include "qerror.h"
+#include "qstring.h"
+#include "sysemu.h"
+#include "qemu-common.h"
+
+static void qerror_destroy_obj(QObject *obj);
+
+static const QType qerror_type = {
+ .code = QTYPE_QERROR,
+ .destroy = qerror_destroy_obj,
+};
+
+/**
+ * The 'desc' parameter is a printf-like string, the format of the format
+ * string is:
+ *
+ * %(KEY)TYPE
+ *
+ * Where KEY is a QDict key and TYPE is the type of its value, KEY and
+ * its value must be passed to qerror_from_info().
+ *
+ * Valid types are:
+ *
+ * s (string)
+ * d (integer)
+ *
+ * Example:
+ *
+ * "foo error on device: %(device)s slot: %(slot_nr)d"
+ *
+ * A single percent sign can be printed if followed by a second one,
+ * for example:
+ *
+ * "running out of foo: %(foo)d%%"
+ */
+const QErrorStringTable qerror_table[] = {
+ {
+ .error_fmt = QERR_DEVICE_NOT_FOUND,
+ .desc = "device \"%(name)s\" not found",
+ },
+ {
+ .error_fmt = QERR_SERVICE_UNAVAILABLE,
+ .desc = "%(reason)s",
+ },
+ {}
+};
+
+/**
+ * qerror_new(): Create a new QError
+ *
+ * Return strong reference.
+ */
+QError *qerror_new(void)
+{
+ QError *qerr;
+
+ qerr = qemu_mallocz(sizeof(*qerr));
+ QOBJECT_INIT(qerr, &qerror_type);
+
+ return qerr;
+}
+
+static void qerror_abort(const QError *qerr, const char *fmt, ...)
+{
+ va_list ap;
+
+ fprintf(stderr, "qerror: ");
+
+ va_start(ap, fmt);
+ vfprintf(stderr, fmt, ap);
+ va_end(ap);
+
+ fprintf(stderr, " call at %s:%d\n", qerr->file, qerr->linenr);
+ abort();
+}
+
+static void qerror_set_data(QError *qerr, const char *fmt, va_list *va)
+{
+ QObject *obj;
+
+ obj = qobject_from_json_va(fmt, va);
+ if (!obj) {
+ qerror_abort(qerr, "invalid format '%s'", fmt);
+ }
+ if (qobject_type(obj) != QTYPE_QDICT) {
+ qerror_abort(qerr, "error format is not a QDict '%s'", fmt);
+ }
+
+ qerr->error = qobject_to_qdict(obj);
+
+ obj = qdict_get(qerr->error, "class");
+ if (!obj) {
+ qerror_abort(qerr, "missing 'class' key in '%s'", fmt);
+ }
+ if (qobject_type(obj) != QTYPE_QSTRING) {
+ qerror_abort(qerr, "'class' key value should be a QString");
+ }
+
+ obj = qdict_get(qerr->error, "data");
+ if (!obj) {
+ qerror_abort(qerr, "missing 'data' key in '%s'", fmt);
+ }
+ if (qobject_type(obj) != QTYPE_QDICT) {
+ qerror_abort(qerr, "'data' key value should be a QDICT");
+ }
+}
+
+static void qerror_set_desc(const char *fmt, QError *qerr)
+{
+ int i;
+
+ // FIXME: inefficient loop
+
+ for (i = 0; qerror_table[i].error_fmt; i++) {
+ if (strcmp(qerror_table[i].error_fmt, fmt) == 0) {
+ qerr->entry = &qerror_table[i];
+ return;
+ }
+ }
+
+ qerror_abort(qerr, "error format '%s' not found", fmt);
+}
+
+/**
+ * qerror_from_info(): Create a new QError from error information
+ *
+ * The information consists of:
+ *
+ * - file the file name of where the error occurred
+ * - linenr the line number of where the error occurred
+ * - fmt JSON printf-like dictionary, there must exist keys 'class' and
+ * 'data'
+ * - va va_list of all arguments specified by fmt
+ *
+ * Return strong reference.
+ */
+QError *qerror_from_info(const char *file, int linenr, const char *fmt,
+ va_list *va)
+{
+ QError *qerr;
+
+ qerr = qerror_new();
+ qerr->linenr = linenr;
+ qerr->file = file;
+
+ if (!fmt) {
+ qerror_abort(qerr, "QDict not specified");
+ }
+
+ qerror_set_data(qerr, fmt, va);
+ qerror_set_desc(fmt, qerr);
+
+ return qerr;
+}
+
+static char *get_substr(const char *start, const char *end)
+{
+ char *str;
+ size_t length;
+
+ length = end - start + 1;
+ str = qemu_malloc(length + 1);
+ memcpy(str, start, length);
+ str[length] = '\0';
+
+ return str;
+}
+
+static void parse_error(const QError *qerror, int c)
+{
+ qerror_abort(qerror, "expected '%c' in '%s'", c, qerror->entry->desc);
+}
+
+static const char *append_field(QString *qstring, const QError *qerror,
+ const char *start)
+{
+ int type;
+ char *name;
+ QDict *qdict;
+ const char *end;
+
+ if (*start != '%')
+ parse_error(qerror, '%');
+ start++;
+ if (*start != '(')
+ parse_error(qerror, '(');
+ start++;
+
+ end = strchr(start, ')');
+ if (!end)
+ parse_error(qerror, ')');
+
+ name = get_substr(start, end - 1);
+ qdict = qobject_to_qdict(qdict_get(qerror->error, "data"));
+
+ if (!qdict_haskey(qdict, name)) {
+ qerror_abort(qerror, "key '%s' not found in QDict", name);
+ }
+
+ type = *++end;
+ switch (type) {
+ case 's':
+ qstring_append(qstring, qdict_get_str(qdict, name));
+ break;
+ case 'd':
+ qstring_append_int(qstring, qdict_get_int(qdict, name));
+ break;
+ default:
+ qerror_abort(qerror, "invalid type '%c'", type);
+ }
+
+ qemu_free(name);
+ return ++end;
+}
+
+/**
+ * qerror_print(): Print QError data
+ *
+ * This function will print the member 'desc' of the specified QError object,
+ * it uses qemu_error() for this, so that the output is routed to the right
+ * place (ie. stderr ou Monitor's device).
+ */
+void qerror_print(const QError *qerror)
+{
+ const char *p;
+ QString *qstring;
+
+ assert(qerror->entry != NULL);
+
+ qstring = qstring_new();
+
+ for (p = qerror->entry->desc; *p != '\0';) {
+ if (*p != '%') {
+ qstring_append_chr(qstring, *p++);
+ } else if (*(p + 1) == '%') {
+ qstring_append_chr(qstring, '%');
+ p += 2;
+ } else {
+ p = append_field(qstring, qerror, p);
+ }
+ }
+
+ qemu_error("%s\n", qstring_get_str(qstring));
+ QDECREF(qstring);
+}
+
+/**
+ * qobject_to_qerror(): Convert a QObject into a QError
+ */
+QError *qobject_to_qerror(const QObject *obj)
+{
+ if (qobject_type(obj) != QTYPE_QERROR) {
+ return NULL;
+ }
+
+ return container_of(obj, QError, base);
+}
+
+/**
+ * qerror_destroy_obj(): Free all memory allocated by a QError
+ */
+static void qerror_destroy_obj(QObject *obj)
+{
+ QError *qerr;
+
+ assert(obj != NULL);
+ qerr = qobject_to_qerror(obj);
+
+ QDECREF(qerr->error);
+ qemu_free(qerr);
+}
new file mode 100644
@@ -0,0 +1,46 @@
+/*
+ * QError header file.
+ *
+ * Copyright (C) 2009 Red Hat Inc.
+ *
+ * Authors:
+ * Luiz Capitulino <lcapitulino@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ */
+#ifndef QERROR_H
+#define QERROR_H
+
+#include "qdict.h"
+#include <stdarg.h>
+
+typedef struct QErrorStringTable {
+ const char *desc;
+ const char *error_fmt;
+} QErrorStringTable;
+
+typedef struct QError {
+ QObject_HEAD;
+ QDict *error;
+ int linenr;
+ const char *file;
+ const QErrorStringTable *entry;
+} QError;
+
+QError *qerror_new(void);
+QError *qerror_from_info(const char *file, int linenr, const char *fmt,
+ va_list *va);
+void qerror_print(const QError *qerror);
+QError *qobject_to_qerror(const QObject *obj);
+
+/*
+ * QEMU error format list
+ */
+#define QERR_DEVICE_NOT_FOUND \
+ "{ 'class': 'DeviceNotFound', 'data': { 'name': %s } }"
+
+#define QERR_SERVICE_UNAVAILABLE \
+ "{ 'class': 'ServiceUnavailable', 'data': { 'reason': %s } }"
+
+#endif /* QERROR_H */
@@ -43,6 +43,7 @@ typedef enum {
QTYPE_QLIST,
QTYPE_QFLOAT,
QTYPE_QBOOL,
+ QTYPE_QERROR,
} qtype_code;
struct QObject;
QError is a high-level data type which represents an exception in QEMU, it stores the following error information: - class Error class name (eg. "ServiceUnavailable") - description A detailed error description, which may contain references to run-time error data - filename The file name of where the error occurred - line number The exact line number of the error - run-time data Any run-time error data This commit adds the basic interface plus two error classes, one for 'device not found' errors and another one for 'service unavailable' errors. Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com> --- Makefile | 2 +- qerror.c | 283 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ qerror.h | 46 ++++++++++ qobject.h | 1 + 4 files changed, 331 insertions(+), 1 deletions(-) create mode 100644 qerror.c create mode 100644 qerror.h