1 /*
2 * Copy one QAPI object to another
3 *
4 * Copyright (C) 2016 Red Hat, Inc.
5 *
6 * This work is licensed under the terms of the GNU GPL, version 2 or later.
7 * See the COPYING file in the top-level directory.
8 *
9 */
10
11 #include "qemu/osdep.h"
12 #include "qapi/clone-visitor.h"
13 #include "qapi/visitor-impl.h"
14 #include "qapi/error.h"
15 #include "qapi/qmp/qnull.h"
16
17 struct QapiCloneVisitor {
18 Visitor visitor;
19 size_t depth;
20 };
21
to_qcv(Visitor * v)22 static QapiCloneVisitor *to_qcv(Visitor *v)
23 {
24 return container_of(v, QapiCloneVisitor, visitor);
25 }
26
qapi_clone_start_struct(Visitor * v,const char * name,void ** obj,size_t size,Error ** errp)27 static bool qapi_clone_start_struct(Visitor *v, const char *name, void **obj,
28 size_t size, Error **errp)
29 {
30 QapiCloneVisitor *qcv = to_qcv(v);
31
32 if (!obj) {
33 assert(qcv->depth);
34 /* Only possible when visiting an alternate's object
35 * branch. Nothing further to do here, since the earlier
36 * visit_start_alternate() already copied memory. */
37 return true;
38 }
39
40 *obj = g_memdup(*obj, size);
41 qcv->depth++;
42 return true;
43 }
44
qapi_clone_end(Visitor * v,void ** obj)45 static void qapi_clone_end(Visitor *v, void **obj)
46 {
47 QapiCloneVisitor *qcv = to_qcv(v);
48
49 assert(qcv->depth);
50 if (obj) {
51 qcv->depth--;
52 }
53 }
54
qapi_clone_start_list(Visitor * v,const char * name,GenericList ** listp,size_t size,Error ** errp)55 static bool qapi_clone_start_list(Visitor *v, const char *name,
56 GenericList **listp, size_t size,
57 Error **errp)
58 {
59 return qapi_clone_start_struct(v, name, (void **)listp, size, errp);
60 }
61
qapi_clone_next_list(Visitor * v,GenericList * tail,size_t size)62 static GenericList *qapi_clone_next_list(Visitor *v, GenericList *tail,
63 size_t size)
64 {
65 QapiCloneVisitor *qcv = to_qcv(v);
66
67 assert(qcv->depth);
68 /* Unshare the tail of the list cloned by g_memdup() */
69 tail->next = g_memdup(tail->next, size);
70 return tail->next;
71 }
72
qapi_clone_start_alternate(Visitor * v,const char * name,GenericAlternate ** obj,size_t size,Error ** errp)73 static bool qapi_clone_start_alternate(Visitor *v, const char *name,
74 GenericAlternate **obj, size_t size,
75 Error **errp)
76 {
77 return qapi_clone_start_struct(v, name, (void **)obj, size, errp);
78 }
79
qapi_clone_type_int64(Visitor * v,const char * name,int64_t * obj,Error ** errp)80 static bool qapi_clone_type_int64(Visitor *v, const char *name, int64_t *obj,
81 Error **errp)
82 {
83 QapiCloneVisitor *qcv = to_qcv(v);
84
85 assert(qcv->depth);
86 /* Value was already cloned by g_memdup() */
87 return true;
88 }
89
qapi_clone_type_uint64(Visitor * v,const char * name,uint64_t * obj,Error ** errp)90 static bool qapi_clone_type_uint64(Visitor *v, const char *name,
91 uint64_t *obj, Error **errp)
92 {
93 QapiCloneVisitor *qcv = to_qcv(v);
94
95 assert(qcv->depth);
96 /* Value was already cloned by g_memdup() */
97 return true;
98 }
99
qapi_clone_type_bool(Visitor * v,const char * name,bool * obj,Error ** errp)100 static bool qapi_clone_type_bool(Visitor *v, const char *name, bool *obj,
101 Error **errp)
102 {
103 QapiCloneVisitor *qcv = to_qcv(v);
104
105 assert(qcv->depth);
106 /* Value was already cloned by g_memdup() */
107 return true;
108 }
109
qapi_clone_type_str(Visitor * v,const char * name,char ** obj,Error ** errp)110 static bool qapi_clone_type_str(Visitor *v, const char *name, char **obj,
111 Error **errp)
112 {
113 QapiCloneVisitor *qcv = to_qcv(v);
114
115 assert(qcv->depth);
116 /*
117 * Pointer was already cloned by g_memdup; create fresh copy.
118 * Note that as long as qobject-output-visitor accepts NULL instead of
119 * "", then we must do likewise. However, we want to obey the
120 * input visitor semantics of never producing NULL when the empty
121 * string is intended.
122 */
123 *obj = g_strdup(*obj ?: "");
124 return true;
125 }
126
qapi_clone_type_number(Visitor * v,const char * name,double * obj,Error ** errp)127 static bool qapi_clone_type_number(Visitor *v, const char *name, double *obj,
128 Error **errp)
129 {
130 QapiCloneVisitor *qcv = to_qcv(v);
131
132 assert(qcv->depth);
133 /* Value was already cloned by g_memdup() */
134 return true;
135 }
136
qapi_clone_type_null(Visitor * v,const char * name,QNull ** obj,Error ** errp)137 static bool qapi_clone_type_null(Visitor *v, const char *name, QNull **obj,
138 Error **errp)
139 {
140 QapiCloneVisitor *qcv = to_qcv(v);
141
142 assert(qcv->depth);
143 *obj = qnull();
144 return true;
145 }
146
qapi_clone_free(Visitor * v)147 static void qapi_clone_free(Visitor *v)
148 {
149 g_free(v);
150 }
151
qapi_clone_visitor_new(void)152 Visitor *qapi_clone_visitor_new(void)
153 {
154 QapiCloneVisitor *v;
155
156 v = g_malloc0(sizeof(*v));
157
158 v->visitor.type = VISITOR_CLONE;
159 v->visitor.start_struct = qapi_clone_start_struct;
160 v->visitor.end_struct = qapi_clone_end;
161 v->visitor.start_list = qapi_clone_start_list;
162 v->visitor.next_list = qapi_clone_next_list;
163 v->visitor.end_list = qapi_clone_end;
164 v->visitor.start_alternate = qapi_clone_start_alternate;
165 v->visitor.end_alternate = qapi_clone_end;
166 v->visitor.type_int64 = qapi_clone_type_int64;
167 v->visitor.type_uint64 = qapi_clone_type_uint64;
168 v->visitor.type_bool = qapi_clone_type_bool;
169 v->visitor.type_str = qapi_clone_type_str;
170 v->visitor.type_number = qapi_clone_type_number;
171 v->visitor.type_null = qapi_clone_type_null;
172 v->visitor.free = qapi_clone_free;
173
174 return &v->visitor;
175 }
176
qapi_clone_members_visitor_new(void)177 Visitor *qapi_clone_members_visitor_new(void)
178 {
179 Visitor *v = qapi_clone_visitor_new();
180 to_qcv(v)->depth++;
181 return v;
182 }
183