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 #include "qobject-internal.h" 16 17 /** 18 * qstring_new(): Create a new empty QString 19 * 20 * Return strong reference. 21 */ 22 QString *qstring_new(void) 23 { 24 return qstring_from_str(""); 25 } 26 27 /** 28 * qstring_get_length(): Get the length of a QString 29 */ 30 size_t qstring_get_length(const QString *qstring) 31 { 32 return qstring->length; 33 } 34 35 /** 36 * qstring_from_substr(): Create a new QString from a C string substring 37 * 38 * Return string reference 39 */ 40 QString *qstring_from_substr(const char *str, size_t start, size_t end) 41 { 42 QString *qstring; 43 44 assert(start <= end); 45 46 qstring = g_malloc(sizeof(*qstring)); 47 qobject_init(QOBJECT(qstring), QTYPE_QSTRING); 48 49 qstring->length = end - start; 50 qstring->capacity = qstring->length; 51 52 assert(qstring->capacity < SIZE_MAX); 53 qstring->string = g_malloc(qstring->capacity + 1); 54 memcpy(qstring->string, str + start, qstring->length); 55 qstring->string[qstring->length] = 0; 56 57 return qstring; 58 } 59 60 /** 61 * qstring_from_str(): Create a new QString from a regular C string 62 * 63 * Return strong reference. 64 */ 65 QString *qstring_from_str(const char *str) 66 { 67 return qstring_from_substr(str, 0, strlen(str)); 68 } 69 70 /** 71 * qstring_from_gstring(): Convert a GString to a QString 72 * 73 * Return strong reference. 74 */ 75 76 QString *qstring_from_gstring(GString *gstr) 77 { 78 QString *qstring; 79 80 qstring = g_malloc(sizeof(*qstring)); 81 qobject_init(QOBJECT(qstring), QTYPE_QSTRING); 82 qstring->length = gstr->len; 83 qstring->capacity = gstr->allocated_len; 84 qstring->string = g_string_free(gstr, false); 85 return qstring; 86 } 87 88 89 static void capacity_increase(QString *qstring, size_t len) 90 { 91 if (qstring->capacity < (qstring->length + len)) { 92 assert(len <= SIZE_MAX - qstring->capacity); 93 qstring->capacity += len; 94 assert(qstring->capacity <= SIZE_MAX / 2); 95 qstring->capacity *= 2; /* use exponential growth */ 96 97 qstring->string = g_realloc(qstring->string, qstring->capacity + 1); 98 } 99 } 100 101 /* qstring_append(): Append a C string to a QString 102 */ 103 void qstring_append(QString *qstring, const char *str) 104 { 105 size_t len = strlen(str); 106 107 capacity_increase(qstring, len); 108 memcpy(qstring->string + qstring->length, str, len); 109 qstring->length += len; 110 qstring->string[qstring->length] = 0; 111 } 112 113 void qstring_append_int(QString *qstring, int64_t value) 114 { 115 char num[32]; 116 117 snprintf(num, sizeof(num), "%" PRId64, value); 118 qstring_append(qstring, num); 119 } 120 121 /** 122 * qstring_append_chr(): Append a C char to a QString 123 */ 124 void qstring_append_chr(QString *qstring, int c) 125 { 126 capacity_increase(qstring, 1); 127 qstring->string[qstring->length++] = c; 128 qstring->string[qstring->length] = 0; 129 } 130 131 /** 132 * qstring_get_str(): Return a pointer to the stored string 133 * 134 * NOTE: Should be used with caution, if the object is deallocated 135 * this pointer becomes invalid. 136 */ 137 const char *qstring_get_str(const QString *qstring) 138 { 139 return qstring->string; 140 } 141 142 /** 143 * qstring_get_try_str(): Return a pointer to the stored string 144 * 145 * NOTE: will return NULL if qstring is not provided. 146 */ 147 const char *qstring_get_try_str(const QString *qstring) 148 { 149 return qstring ? qstring_get_str(qstring) : NULL; 150 } 151 152 /** 153 * qobject_get_try_str(): Return a pointer to the corresponding string 154 * 155 * NOTE: the string will only be returned if the object is valid, and 156 * its type is QString, otherwise NULL is returned. 157 */ 158 const char *qobject_get_try_str(const QObject *qstring) 159 { 160 return qstring_get_try_str(qobject_to(QString, qstring)); 161 } 162 163 /** 164 * qstring_is_equal(): Test whether the two QStrings are equal 165 */ 166 bool qstring_is_equal(const QObject *x, const QObject *y) 167 { 168 return !strcmp(qobject_to(QString, x)->string, 169 qobject_to(QString, y)->string); 170 } 171 172 /** 173 * qstring_destroy_obj(): Free all memory allocated by a QString 174 * object 175 */ 176 void qstring_destroy_obj(QObject *obj) 177 { 178 QString *qs; 179 180 assert(obj != NULL); 181 qs = qobject_to(QString, obj); 182 g_free(qs->string); 183 g_free(qs); 184 } 185