Update version for v5.1.0 release
[qemu.git] / qobject / qstring.c
1 /*
2 * QString Module
3 *
4 * Copyright (C) 2009 Red Hat Inc.
5 *
6 * Authors:
7 * Luiz Capitulino <lcapitulino@redhat.com>
8 *
9 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
10 * See the COPYING.LIB file in the top-level directory.
11 */
12
13 #include "qemu/osdep.h"
14 #include "qapi/qmp/qstring.h"
15
16 /**
17 * qstring_new(): Create a new empty QString
18 *
19 * Return strong reference.
20 */
21 QString *qstring_new(void)
22 {
23 return qstring_from_str("");
24 }
25
26 /**
27 * qstring_get_length(): Get the length of a QString
28 */
29 size_t qstring_get_length(const QString *qstring)
30 {
31 return qstring->length;
32 }
33
34 /**
35 * qstring_from_substr(): Create a new QString from a C string substring
36 *
37 * Return string reference
38 */
39 QString *qstring_from_substr(const char *str, size_t start, size_t end)
40 {
41 QString *qstring;
42
43 assert(start <= end);
44
45 qstring = g_malloc(sizeof(*qstring));
46 qobject_init(QOBJECT(qstring), QTYPE_QSTRING);
47
48 qstring->length = end - start;
49 qstring->capacity = qstring->length;
50
51 assert(qstring->capacity < SIZE_MAX);
52 qstring->string = g_malloc(qstring->capacity + 1);
53 memcpy(qstring->string, str + start, qstring->length);
54 qstring->string[qstring->length] = 0;
55
56 return qstring;
57 }
58
59 /**
60 * qstring_from_str(): Create a new QString from a regular C string
61 *
62 * Return strong reference.
63 */
64 QString *qstring_from_str(const char *str)
65 {
66 return qstring_from_substr(str, 0, strlen(str));
67 }
68
69 static void capacity_increase(QString *qstring, size_t len)
70 {
71 if (qstring->capacity < (qstring->length + len)) {
72 assert(len <= SIZE_MAX - qstring->capacity);
73 qstring->capacity += len;
74 assert(qstring->capacity <= SIZE_MAX / 2);
75 qstring->capacity *= 2; /* use exponential growth */
76
77 qstring->string = g_realloc(qstring->string, qstring->capacity + 1);
78 }
79 }
80
81 /* qstring_append(): Append a C string to a QString
82 */
83 void qstring_append(QString *qstring, const char *str)
84 {
85 size_t len = strlen(str);
86
87 capacity_increase(qstring, len);
88 memcpy(qstring->string + qstring->length, str, len);
89 qstring->length += len;
90 qstring->string[qstring->length] = 0;
91 }
92
93 void qstring_append_int(QString *qstring, int64_t value)
94 {
95 char num[32];
96
97 snprintf(num, sizeof(num), "%" PRId64, value);
98 qstring_append(qstring, num);
99 }
100
101 /**
102 * qstring_append_chr(): Append a C char to a QString
103 */
104 void qstring_append_chr(QString *qstring, int c)
105 {
106 capacity_increase(qstring, 1);
107 qstring->string[qstring->length++] = c;
108 qstring->string[qstring->length] = 0;
109 }
110
111 /**
112 * qstring_get_str(): Return a pointer to the stored string
113 *
114 * NOTE: Should be used with caution, if the object is deallocated
115 * this pointer becomes invalid.
116 */
117 const char *qstring_get_str(const QString *qstring)
118 {
119 return qstring->string;
120 }
121
122 /**
123 * qstring_get_try_str(): Return a pointer to the stored string
124 *
125 * NOTE: will return NULL if qstring is not provided.
126 */
127 const char *qstring_get_try_str(const QString *qstring)
128 {
129 return qstring ? qstring_get_str(qstring) : NULL;
130 }
131
132 /**
133 * qobject_get_try_str(): Return a pointer to the corresponding string
134 *
135 * NOTE: the string will only be returned if the object is valid, and
136 * its type is QString, otherwise NULL is returned.
137 */
138 const char *qobject_get_try_str(const QObject *qstring)
139 {
140 return qstring_get_try_str(qobject_to(QString, qstring));
141 }
142
143 /**
144 * qstring_is_equal(): Test whether the two QStrings are equal
145 */
146 bool qstring_is_equal(const QObject *x, const QObject *y)
147 {
148 return !strcmp(qobject_to(QString, x)->string,
149 qobject_to(QString, y)->string);
150 }
151
152 /**
153 * qstring_free(): Free the memory allocated by a QString object
154 *
155 * Return: if @return_str, return the underlying string, to be
156 * g_free(), otherwise NULL is returned.
157 */
158 char *qstring_free(QString *qstring, bool return_str)
159 {
160 char *rv = NULL;
161
162 if (return_str) {
163 rv = qstring->string;
164 } else {
165 g_free(qstring->string);
166 }
167
168 g_free(qstring);
169
170 return rv;
171 }
172
173 /**
174 * qstring_destroy_obj(): Free all memory allocated by a QString
175 * object
176 */
177 void qstring_destroy_obj(QObject *obj)
178 {
179 assert(obj != NULL);
180 qstring_free(qobject_to(QString, obj), FALSE);
181 }