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 "qapi/qmp/qobject.h" 14 #include "qapi/qmp/qstring.h" 15 #include "qemu-common.h" 16 17 static void qstring_destroy_obj(QObject *obj); 18 19 static const QType qstring_type = { 20 .code = QTYPE_QSTRING, 21 .destroy = qstring_destroy_obj, 22 }; 23 24 /** 25 * qstring_new(): Create a new empty QString 26 * 27 * Return strong reference. 28 */ 29 QString *qstring_new(void) 30 { 31 return qstring_from_str(""); 32 } 33 34 /** 35 * qstring_get_length(): Get the length of a QString 36 */ 37 size_t qstring_get_length(const QString *qstring) 38 { 39 return qstring->length; 40 } 41 42 /** 43 * qstring_from_substr(): Create a new QString from a C string substring 44 * 45 * Return string reference 46 */ 47 QString *qstring_from_substr(const char *str, int start, int end) 48 { 49 QString *qstring; 50 51 qstring = g_malloc(sizeof(*qstring)); 52 53 qstring->length = end - start + 1; 54 qstring->capacity = qstring->length; 55 56 qstring->string = g_malloc(qstring->capacity + 1); 57 memcpy(qstring->string, str + start, qstring->length); 58 qstring->string[qstring->length] = 0; 59 60 QOBJECT_INIT(qstring, &qstring_type); 61 62 return qstring; 63 } 64 65 /** 66 * qstring_from_str(): Create a new QString from a regular C string 67 * 68 * Return strong reference. 69 */ 70 QString *qstring_from_str(const char *str) 71 { 72 return qstring_from_substr(str, 0, strlen(str) - 1); 73 } 74 75 static void capacity_increase(QString *qstring, size_t len) 76 { 77 if (qstring->capacity < (qstring->length + len)) { 78 qstring->capacity += len; 79 qstring->capacity *= 2; /* use exponential growth */ 80 81 qstring->string = g_realloc(qstring->string, qstring->capacity + 1); 82 } 83 } 84 85 /* qstring_append(): Append a C string to a QString 86 */ 87 void qstring_append(QString *qstring, const char *str) 88 { 89 size_t len = strlen(str); 90 91 capacity_increase(qstring, len); 92 memcpy(qstring->string + qstring->length, str, len); 93 qstring->length += len; 94 qstring->string[qstring->length] = 0; 95 } 96 97 void qstring_append_int(QString *qstring, int64_t value) 98 { 99 char num[32]; 100 101 snprintf(num, sizeof(num), "%" PRId64, value); 102 qstring_append(qstring, num); 103 } 104 105 /** 106 * qstring_append_chr(): Append a C char to a QString 107 */ 108 void qstring_append_chr(QString *qstring, int c) 109 { 110 capacity_increase(qstring, 1); 111 qstring->string[qstring->length++] = c; 112 qstring->string[qstring->length] = 0; 113 } 114 115 /** 116 * qobject_to_qstring(): Convert a QObject to a QString 117 */ 118 QString *qobject_to_qstring(const QObject *obj) 119 { 120 if (qobject_type(obj) != QTYPE_QSTRING) 121 return NULL; 122 123 return container_of(obj, QString, base); 124 } 125 126 /** 127 * qstring_get_str(): Return a pointer to the stored string 128 * 129 * NOTE: Should be used with caution, if the object is deallocated 130 * this pointer becomes invalid. 131 */ 132 const char *qstring_get_str(const QString *qstring) 133 { 134 return qstring->string; 135 } 136 137 /** 138 * qstring_destroy_obj(): Free all memory allocated by a QString 139 * object 140 */ 141 static void qstring_destroy_obj(QObject *obj) 142 { 143 QString *qs; 144 145 assert(obj != NULL); 146 qs = qobject_to_qstring(obj); 147 g_free(qs->string); 148 g_free(qs); 149 } 150