[Qemu-devel] [RFC 3/8] qapi: add QemuFileInputVisitor

[Michael Roth <mdroth@linux.vnet.ibm.com>]

Visitor interfaces to read values from a QEMUFile

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 Makefile.objs                  |    1 +
 qapi/qemu-file-input-visitor.c |  350 ++++++++++++++++++++++++++++++++++++++++
 qapi/qemu-file-input-visitor.h |   26 +++
 3 files changed, 377 insertions(+), 0 deletions(-)
 create mode 100644 qapi/qemu-file-input-visitor.c
 create mode 100644 qapi/qemu-file-input-visitor.h

diff --git a/Makefile.objs b/Makefile.objs
index 48fe0c4..6bc8555 100644
--- a/Makefile.objs
+++ b/Makefile.objs
@@ -82,6 +82,7 @@ fsdev-obj-$(CONFIG_VIRTFS) += $(addprefix fsdev/, $(fsdev-nested-y))
 common-obj-y = $(block-obj-y) blockdev.o
 common-obj-y += $(qapi-obj-y)
 common-obj-y += qapi/qemu-file-output-visitor.o
+common-obj-y += qapi/qemu-file-input-visitor.o
 common-obj-y += $(net-obj-y)
 common-obj-y += $(qobject-obj-y)
 common-obj-$(CONFIG_LINUX) += $(fsdev-obj-$(CONFIG_LINUX))
diff --git a/qapi/qemu-file-input-visitor.c b/qapi/qemu-file-input-visitor.c
new file mode 100644
index 0000000..7217125
--- /dev/null
+++ b/qapi/qemu-file-input-visitor.c
@@ -0,0 +1,350 @@
+/*
+ * QEMUFile Output Visitor
+ *
+ * Copyright IBM, Corp. 2011
+ *
+ * Authors:
+ *  Michael Roth   <mdroth@linux.vnet.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
+ * See the COPYING.LIB file in the top-level directory.
+ *
+ */
+
+#include "qemu-file-input-visitor.h"
+#include "qemu-queue.h"
+#include "qemu-common.h"
+#include "qemu-objects.h"
+#include "hw/hw.h"
+#include "qerror.h"
+
+typedef struct {
+    size_t elem_count;
+    size_t elem_size;
+    size_t pos;
+} ArrayInfo;
+
+typedef struct StackEntry
+{
+    enum {
+        QFIV_ARRAY,
+        QFIV_LIST,
+        QFIV_STRUCT,
+    } type;
+    ArrayInfo array_info;
+    QTAILQ_ENTRY(StackEntry) node;
+} StackEntry;
+
+struct QemuFileInputVisitor
+{
+    Visitor visitor;
+    QTAILQ_HEAD(, StackEntry) stack;
+    QEMUFile *file;
+};
+
+static QemuFileInputVisitor *to_iv(Visitor *v)
+{
+    return container_of(v, QemuFileInputVisitor, visitor);
+}
+
+static void qemu_file_input_push(QemuFileInputVisitor *iv, StackEntry *e)
+{
+    QTAILQ_INSERT_HEAD(&iv->stack, e, node);
+}
+
+static void qemu_file_input_push_array(QemuFileInputVisitor *iv, ArrayInfo ai)
+{
+    StackEntry *e = g_malloc0(sizeof(*e));
+    e->type = QFIV_ARRAY;
+    e->array_info = ai;
+    qemu_file_input_push(iv, e);
+}
+
+static void qemu_file_input_push_list(QemuFileInputVisitor *iv)
+{
+    StackEntry *e = g_malloc0(sizeof(*e));
+    e->type = QFIV_LIST;
+    qemu_file_input_push(iv, e);
+}
+
+static void qemu_file_input_push_struct(QemuFileInputVisitor *iv)
+{
+    StackEntry *e = g_malloc0(sizeof(*e));
+    e->type = QFIV_STRUCT;
+    qemu_file_input_push(iv, e);
+}
+
+static void *qemu_file_input_pop(QemuFileInputVisitor *iv)
+{
+    StackEntry *e = QTAILQ_FIRST(&iv->stack);
+    QTAILQ_REMOVE(&iv->stack, e, node);
+    return e;
+}
+
+static bool qemu_file_input_is_array(QemuFileInputVisitor *iv)
+{
+    StackEntry *e = QTAILQ_FIRST(&iv->stack);
+    return e->type == QFIV_ARRAY;
+}
+
+static bool qemu_file_input_is_list(QemuFileInputVisitor *ov)
+{
+    StackEntry *e = QTAILQ_FIRST(&ov->stack);
+    return e && e->type == QFIV_LIST;
+}
+
+static void qemu_file_input_start_struct(Visitor *v, void **obj,
+                                         const char *kind,
+                                         const char *name, size_t size,
+                                         Error **errp)
+{
+    QemuFileInputVisitor *iv = to_iv(v);
+
+    if (obj && *obj == NULL) {
+        *obj = g_malloc0(size);
+    }
+    qemu_file_input_push_struct(iv);
+}
+
+static void qemu_file_input_end_struct(Visitor *v, Error **errp)
+{
+    QemuFileInputVisitor *iv = to_iv(v);
+    StackEntry *e = qemu_file_input_pop(iv);
+
+    if (!e || e->type != QFIV_STRUCT) {
+        error_set(errp, QERR_UNDEFINED_ERROR);
+        return;
+    }
+    g_free(e);
+}
+
+static void qemu_file_input_start_list(Visitor *v, const char *name,
+                                       Error **errp)
+{
+    QemuFileInputVisitor *iv = to_iv(v);
+    qemu_file_input_push_list(iv);
+}
+
+static GenericList *qemu_file_input_next_list(Visitor *v, GenericList **list,
+                                           Error **errp)
+{
+    QemuFileInputVisitor *iv = to_iv(v);
+    GenericList *entry;
+
+    if (!qemu_file_input_is_list(iv)) {
+        error_set(errp, QERR_UNDEFINED_ERROR);
+    }
+
+    entry = g_malloc0(sizeof(*entry));
+    if (*list) {
+        (*list)->next = entry;
+    }
+
+    *list = entry;
+    return entry;
+}
+
+static void qemu_file_input_end_list(Visitor *v, Error **errp)
+{
+    QemuFileInputVisitor *iv = to_iv(v);
+    StackEntry *e = qemu_file_input_pop(iv);
+    if (!e || e->type != QFIV_LIST) {
+        error_set(errp, QERR_UNDEFINED_ERROR);
+        return;
+    }
+    g_free(e);
+}
+
+static void qemu_file_input_start_array(Visitor *v, void **obj,
+                                        const char *name,
+                                        size_t elem_count,
+                                        size_t elem_size,
+                                        Error **errp)
+{
+    QemuFileInputVisitor *iv = to_iv(v);
+    ArrayInfo ai = {
+        .elem_count = elem_count,
+        .elem_size = elem_size,
+        .pos = 0
+    };
+    if (*obj == NULL) {
+        *obj = g_malloc0(elem_count * elem_size);
+    }
+    qemu_file_input_push_array(iv, ai);
+}
+
+static void qemu_file_input_next_array(Visitor *v, Error **errp)
+{
+    QemuFileInputVisitor *iv = to_iv(v);
+    StackEntry *e = QTAILQ_FIRST(&iv->stack);
+
+    if (!qemu_file_input_is_array(iv) ||
+        e->array_info.pos >= e->array_info.elem_count) {
+        error_set(errp, QERR_UNDEFINED_ERROR);
+    }
+
+    e->array_info.pos++;
+}
+
+static void qemu_file_input_end_array(Visitor *v, Error **errp)
+{
+    QemuFileInputVisitor *iv = to_iv(v);
+    StackEntry *e = qemu_file_input_pop(iv);
+    if (!e || e->type != QFIV_ARRAY) {
+        error_set(errp, QERR_UNDEFINED_ERROR);
+        return;
+    }
+    g_free(e);
+}
+
+static void qemu_file_input_type_str(Visitor *v, char **obj, const char *name,
+                                  Error **errp)
+{
+    if (obj) {
+        g_free(*obj);
+    }
+}
+
+static void qemu_file_input_type_uint8_t(Visitor *v, uint8_t *obj,
+                                         const char *name, Error **errp)
+{
+    QemuFileInputVisitor *ov = container_of(v, QemuFileInputVisitor, visitor);
+    *obj = qemu_get_byte(ov->file);
+}
+
+static void qemu_file_input_type_uint16_t(Visitor *v, uint16_t *obj,
+                                          const char *name, Error **errp)
+{
+    QemuFileInputVisitor *ov = container_of(v, QemuFileInputVisitor, visitor);
+    *obj = qemu_get_byte(ov->file) << 8;
+    *obj |= qemu_get_byte(ov->file);
+}
+
+static void qemu_file_input_type_uint32_t(Visitor *v, uint32_t *obj,
+                                          const char *name, Error **errp)
+{
+    QemuFileInputVisitor *ov = container_of(v, QemuFileInputVisitor, visitor);
+    *obj = qemu_get_byte(ov->file) << 24;
+    *obj |= qemu_get_byte(ov->file) << 16;
+    *obj |= qemu_get_byte(ov->file) << 8;
+    *obj |= qemu_get_byte(ov->file);
+}
+
+static void qemu_file_input_type_uint64_t(Visitor *v, uint64_t *obj,
+                                          const char *name, Error **errp)
+{
+    QemuFileInputVisitor *ov = container_of(v, QemuFileInputVisitor, visitor);
+    *obj = (uint64_t)qemu_get_byte(ov->file) << 56;
+    *obj |= (uint64_t)qemu_get_byte(ov->file) << 48;
+    *obj |= (uint64_t)qemu_get_byte(ov->file) << 40;
+    *obj |= (uint64_t)qemu_get_byte(ov->file) << 32;
+    *obj |= qemu_get_byte(ov->file) << 24;
+    *obj |= qemu_get_byte(ov->file) << 16;
+    *obj |= qemu_get_byte(ov->file) << 8;
+    *obj |= qemu_get_byte(ov->file);
+}
+
+static void qemu_file_input_type_int8_t(Visitor *v, int8_t *obj,
+                                        const char *name, Error **errp)
+{
+    QemuFileInputVisitor *ov = container_of(v, QemuFileInputVisitor, visitor);
+    *obj = qemu_get_sbyte(ov->file);
+}
+
+static void qemu_file_input_type_int16_t(Visitor *v, int16_t *obj,
+                                         const char *name, Error **errp)
+{
+    QemuFileInputVisitor *ov = container_of(v, QemuFileInputVisitor, visitor);
+    *obj = qemu_get_sbyte(ov->file) << 8;
+    *obj |= qemu_get_sbyte(ov->file);
+}
+
+static void qemu_file_input_type_int32_t(Visitor *v, int32_t *obj,
+                                         const char *name, Error **errp)
+{
+    QemuFileInputVisitor *ov = container_of(v, QemuFileInputVisitor, visitor);
+    *obj = qemu_get_sbyte(ov->file) << 24;
+    *obj |= qemu_get_sbyte(ov->file) << 16;
+    *obj |= qemu_get_sbyte(ov->file) << 8;
+    *obj |= qemu_get_sbyte(ov->file);
+}
+
+static void qemu_file_input_type_int64_t(Visitor *v, int64_t *obj,
+                                         const char *name, Error **errp)
+{
+    QemuFileInputVisitor *ov = container_of(v, QemuFileInputVisitor, visitor);
+    *obj = (int64_t)qemu_get_sbyte(ov->file) << 56;
+    *obj |= (int64_t)qemu_get_sbyte(ov->file) << 48;
+    *obj |= (int64_t)qemu_get_sbyte(ov->file) << 40;
+    *obj |= (int64_t)qemu_get_sbyte(ov->file) << 32;
+    *obj |= qemu_get_sbyte(ov->file) << 24;
+    *obj |= qemu_get_sbyte(ov->file) << 16;
+    *obj |= qemu_get_sbyte(ov->file) << 8;
+    *obj |= qemu_get_sbyte(ov->file);
+}
+
+static void qemu_file_input_type_bool(Visitor *v, bool *obj, const char *name,
+                                     Error **errp)
+{
+    uint8_t val;
+    qemu_file_input_type_uint8_t(v, &val, name, errp);
+    *obj = val;
+}
+
+static void qemu_file_input_type_number(Visitor *v, double *obj,
+                                        const char *name, Error **errp)
+{
+    uint64_t *val = (uint64_t *)obj;
+    qemu_file_input_type_uint64_t(v, val, name, errp);
+}
+
+static void qemu_file_input_type_enum(Visitor *v, int *obj,
+                                      const char *strings[], const char *kind,
+                                      const char *name, Error **errp)
+{
+}
+
+Visitor *qemu_file_input_get_visitor(QemuFileInputVisitor *ov)
+{
+    return &ov->visitor;
+}
+
+void qemu_file_input_visitor_cleanup(QemuFileInputVisitor *ov)
+{
+    g_free(ov);
+}
+
+QemuFileInputVisitor *qemu_file_input_visitor_new(QEMUFile *f)
+{
+    QemuFileInputVisitor *v;
+
+    v = g_malloc0(sizeof(*v));
+
+    v->file = f;
+
+    v->visitor.start_struct = qemu_file_input_start_struct;
+    v->visitor.end_struct = qemu_file_input_end_struct;
+    v->visitor.start_list = qemu_file_input_start_list;
+    v->visitor.next_list = qemu_file_input_next_list;
+    v->visitor.end_list = qemu_file_input_end_list;
+    v->visitor.start_array = qemu_file_input_start_array;
+    v->visitor.next_array = qemu_file_input_next_array;
+    v->visitor.end_array = qemu_file_input_end_array;
+    v->visitor.type_enum = qemu_file_input_type_enum;
+    v->visitor.type_int = qemu_file_input_type_int64_t;
+    v->visitor.type_uint8_t = qemu_file_input_type_uint8_t;
+    v->visitor.type_uint16_t = qemu_file_input_type_uint16_t;
+    v->visitor.type_uint32_t = qemu_file_input_type_uint32_t;
+    v->visitor.type_uint64_t = qemu_file_input_type_uint64_t;
+    v->visitor.type_int8_t = qemu_file_input_type_int8_t;
+    v->visitor.type_int16_t = qemu_file_input_type_int16_t;
+    v->visitor.type_int32_t = qemu_file_input_type_int32_t;
+    v->visitor.type_int64_t = qemu_file_input_type_int64_t;
+    v->visitor.type_bool = qemu_file_input_type_bool;
+    v->visitor.type_str = qemu_file_input_type_str;
+    v->visitor.type_number = qemu_file_input_type_number;
+
+    QTAILQ_INIT(&v->stack);
+
+    return v;
+}
diff --git a/qapi/qemu-file-input-visitor.h b/qapi/qemu-file-input-visitor.h
new file mode 100644
index 0000000..67b5554
--- /dev/null
+++ b/qapi/qemu-file-input-visitor.h
@@ -0,0 +1,26 @@
+/*
+ * QEMUFile Visitor
+ *
+ * Copyright IBM, Corp. 2011
+ *
+ * Authors:
+ *  Michael Roth   <mdroth@linux.vnet.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
+ * See the COPYING.LIB file in the top-level directory.
+ *
+ */
+
+#ifndef QEMU_FILE_INPUT_VISITOR_H
+#define QEMU_FILE_INPUT_VISITOR_H
+
+#include "qapi-visit-core.h"
+
+typedef struct QemuFileInputVisitor QemuFileInputVisitor;
+
+QemuFileInputVisitor *qemu_file_input_visitor_new(QEMUFile *f);
+void qemu_file_input_visitor_cleanup(QemuFileInputVisitor *d);
+
+Visitor *qemu_file_input_get_visitor(QemuFileInputVisitor *v);
+
+#endif
-- 
1.7.0.4