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