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 | |
22 | static QapiCloneVisitor *to_qcv(Visitor *v) |
23 | { |
24 | return container_of(v, QapiCloneVisitor, visitor); |
25 | } |
26 | |
27 | static void 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; |
38 | } |
39 | |
40 | *obj = g_memdup(*obj, size); |
41 | qcv->depth++; |
42 | } |
43 | |
44 | static void qapi_clone_end(Visitor *v, void **obj) |
45 | { |
46 | QapiCloneVisitor *qcv = to_qcv(v); |
47 | |
48 | assert(qcv->depth); |
49 | if (obj) { |
50 | qcv->depth--; |
51 | } |
52 | } |
53 | |
54 | static void qapi_clone_start_list(Visitor *v, const char *name, |
55 | GenericList **listp, size_t size, |
56 | Error **errp) |
57 | { |
58 | qapi_clone_start_struct(v, name, (void **)listp, size, errp); |
59 | } |
60 | |
61 | static GenericList *qapi_clone_next_list(Visitor *v, GenericList *tail, |
62 | size_t size) |
63 | { |
64 | QapiCloneVisitor *qcv = to_qcv(v); |
65 | |
66 | assert(qcv->depth); |
67 | /* Unshare the tail of the list cloned by g_memdup() */ |
68 | tail->next = g_memdup(tail->next, size); |
69 | return tail->next; |
70 | } |
71 | |
72 | static void qapi_clone_start_alternate(Visitor *v, const char *name, |
73 | GenericAlternate **obj, size_t size, |
74 | Error **errp) |
75 | { |
76 | qapi_clone_start_struct(v, name, (void **)obj, size, errp); |
77 | } |
78 | |
79 | static void qapi_clone_type_int64(Visitor *v, const char *name, int64_t *obj, |
80 | Error **errp) |
81 | { |
82 | QapiCloneVisitor *qcv = to_qcv(v); |
83 | |
84 | assert(qcv->depth); |
85 | /* Value was already cloned by g_memdup() */ |
86 | } |
87 | |
88 | static void qapi_clone_type_uint64(Visitor *v, const char *name, |
89 | uint64_t *obj, Error **errp) |
90 | { |
91 | QapiCloneVisitor *qcv = to_qcv(v); |
92 | |
93 | assert(qcv->depth); |
94 | /* Value was already cloned by g_memdup() */ |
95 | } |
96 | |
97 | static void qapi_clone_type_bool(Visitor *v, const char *name, bool *obj, |
98 | Error **errp) |
99 | { |
100 | QapiCloneVisitor *qcv = to_qcv(v); |
101 | |
102 | assert(qcv->depth); |
103 | /* Value was already cloned by g_memdup() */ |
104 | } |
105 | |
106 | static void qapi_clone_type_str(Visitor *v, const char *name, char **obj, |
107 | Error **errp) |
108 | { |
109 | QapiCloneVisitor *qcv = to_qcv(v); |
110 | |
111 | assert(qcv->depth); |
112 | /* |
113 | * Pointer was already cloned by g_memdup; create fresh copy. |
114 | * Note that as long as qobject-output-visitor accepts NULL instead of |
115 | * "", then we must do likewise. However, we want to obey the |
116 | * input visitor semantics of never producing NULL when the empty |
117 | * string is intended. |
118 | */ |
119 | *obj = g_strdup(*obj ?: "" ); |
120 | } |
121 | |
122 | static void qapi_clone_type_number(Visitor *v, const char *name, double *obj, |
123 | Error **errp) |
124 | { |
125 | QapiCloneVisitor *qcv = to_qcv(v); |
126 | |
127 | assert(qcv->depth); |
128 | /* Value was already cloned by g_memdup() */ |
129 | } |
130 | |
131 | static void qapi_clone_type_null(Visitor *v, const char *name, QNull **obj, |
132 | Error **errp) |
133 | { |
134 | QapiCloneVisitor *qcv = to_qcv(v); |
135 | |
136 | assert(qcv->depth); |
137 | *obj = qnull(); |
138 | } |
139 | |
140 | static void qapi_clone_free(Visitor *v) |
141 | { |
142 | g_free(v); |
143 | } |
144 | |
145 | static Visitor *qapi_clone_visitor_new(void) |
146 | { |
147 | QapiCloneVisitor *v; |
148 | |
149 | v = g_malloc0(sizeof(*v)); |
150 | |
151 | v->visitor.type = VISITOR_CLONE; |
152 | v->visitor.start_struct = qapi_clone_start_struct; |
153 | v->visitor.end_struct = qapi_clone_end; |
154 | v->visitor.start_list = qapi_clone_start_list; |
155 | v->visitor.next_list = qapi_clone_next_list; |
156 | v->visitor.end_list = qapi_clone_end; |
157 | v->visitor.start_alternate = qapi_clone_start_alternate; |
158 | v->visitor.end_alternate = qapi_clone_end; |
159 | v->visitor.type_int64 = qapi_clone_type_int64; |
160 | v->visitor.type_uint64 = qapi_clone_type_uint64; |
161 | v->visitor.type_bool = qapi_clone_type_bool; |
162 | v->visitor.type_str = qapi_clone_type_str; |
163 | v->visitor.type_number = qapi_clone_type_number; |
164 | v->visitor.type_null = qapi_clone_type_null; |
165 | v->visitor.free = qapi_clone_free; |
166 | |
167 | return &v->visitor; |
168 | } |
169 | |
170 | void *qapi_clone(const void *src, void (*visit_type)(Visitor *, const char *, |
171 | void **, Error **)) |
172 | { |
173 | Visitor *v; |
174 | void *dst = (void *) src; /* Cast away const */ |
175 | |
176 | if (!src) { |
177 | return NULL; |
178 | } |
179 | |
180 | v = qapi_clone_visitor_new(); |
181 | visit_type(v, NULL, &dst, &error_abort); |
182 | visit_free(v); |
183 | return dst; |
184 | } |
185 | |
186 | void qapi_clone_members(void *dst, const void *src, size_t sz, |
187 | void (*visit_type_members)(Visitor *, void *, |
188 | Error **)) |
189 | { |
190 | Visitor *v; |
191 | |
192 | v = qapi_clone_visitor_new(); |
193 | memcpy(dst, src, sz); |
194 | to_qcv(v)->depth++; |
195 | visit_type_members(v, dst, &error_abort); |
196 | visit_free(v); |
197 | } |
198 | |