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 /** 70 * qstring_from_gstring(): Convert a GString to a QString 71 * 72 * Return strong reference. 73 */ 74 75 QString *qstring_from_gstring(GString *gstr) 76 { 77 QString *qstring; 78 79 qstring = g_malloc(sizeof(*qstring)); 80 qobject_init(QOBJECT(qstring), QTYPE_QSTRING); 81 qstring->length = gstr->len; 82 qstring->capacity = gstr->allocated_len; 83 qstring->string = g_string_free(gstr, false); 84 return qstring; 85 } 86 87 88 static void capacity_increase(QString *qstring, size_t len) 89 { 90 if (qstring->capacity < (qstring->length + len)) { 91 assert(len <= SIZE_MAX - qstring->capacity); 92 qstring->capacity += len; 93 assert(qstring->capacity <= SIZE_MAX / 2); 94 qstring->capacity *= 2; /* use exponential growth */ 95 96 qstring->string = g_realloc(qstring->string, qstring->capacity + 1); 97 } 98 } 99 100 /* qstring_append(): Append a C string to a QString 101 */ 102 void qstring_append(QString *qstring, const char *str) 103 { 104 size_t len = strlen(str); 105 106 capacity_increase(qstring, len); 107 memcpy(qstring->string + qstring->length, str, len); 108 qstring->length += len; 109 qstring->string[qstring->length] = 0; 110 } 111 112 void qstring_append_int(QString *qstring, int64_t value) 113 { 114 char num[32]; 115 116 snprintf(num, sizeof(num), "%" PRId64, value); 117 qstring_append(qstring, num); 118 } 119 120 /** 121 * qstring_append_chr(): Append a C char to a QString 122 */ 123 void qstring_append_chr(QString *qstring, int c) 124 { 125 capacity_increase(qstring, 1); 126 qstring->string[qstring->length++] = c; 127 qstring->string[qstring->length] = 0; 128 } 129 130 /** 131 * qstring_get_str(): Return a pointer to the stored string 132 * 133 * NOTE: Should be used with caution, if the object is deallocated 134 * this pointer becomes invalid. 135 */ 136 const char *qstring_get_str(const QString *qstring) 137 { 138 return qstring->string; 139 } 140 141 /** 142 * qstring_get_try_str(): Return a pointer to the stored string 143 * 144 * NOTE: will return NULL if qstring is not provided. 145 */ 146 const char *qstring_get_try_str(const QString *qstring) 147 { 148 return qstring ? qstring_get_str(qstring) : NULL; 149 } 150 151 /** 152 * qobject_get_try_str(): Return a pointer to the corresponding string 153 * 154 * NOTE: the string will only be returned if the object is valid, and 155 * its type is QString, otherwise NULL is returned. 156 */ 157 const char *qobject_get_try_str(const QObject *qstring) 158 { 159 return qstring_get_try_str(qobject_to(QString, qstring)); 160 } 161 162 /** 163 * qstring_is_equal(): Test whether the two QStrings are equal 164 */ 165 bool qstring_is_equal(const QObject *x, const QObject *y) 166 { 167 return !strcmp(qobject_to(QString, x)->string, 168 qobject_to(QString, y)->string); 169 } 170 171 /** 172 * qstring_destroy_obj(): Free all memory allocated by a QString 173 * object 174 */ 175 void qstring_destroy_obj(QObject *obj) 176 { 177 QString *qs; 178 179 assert(obj != NULL); 180 qs = qobject_to(QString, obj); 181 g_free(qs->string); 182 g_free(qs); 183 } 184