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 /** 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, int start, int end) 41 { 42 QString *qstring; 43 44 qstring = g_malloc(sizeof(*qstring)); 45 qobject_init(QOBJECT(qstring), QTYPE_QSTRING); 46 47 qstring->length = end - start + 1; 48 qstring->capacity = qstring->length; 49 50 qstring->string = g_malloc(qstring->capacity + 1); 51 memcpy(qstring->string, str + start, qstring->length); 52 qstring->string[qstring->length] = 0; 53 54 55 return qstring; 56 } 57 58 /** 59 * qstring_from_str(): Create a new QString from a regular C string 60 * 61 * Return strong reference. 62 */ 63 QString *qstring_from_str(const char *str) 64 { 65 return qstring_from_substr(str, 0, strlen(str) - 1); 66 } 67 68 static void capacity_increase(QString *qstring, size_t len) 69 { 70 if (qstring->capacity < (qstring->length + len)) { 71 qstring->capacity += len; 72 qstring->capacity *= 2; /* use exponential growth */ 73 74 qstring->string = g_realloc(qstring->string, qstring->capacity + 1); 75 } 76 } 77 78 /* qstring_append(): Append a C string to a QString 79 */ 80 void qstring_append(QString *qstring, const char *str) 81 { 82 size_t len = strlen(str); 83 84 capacity_increase(qstring, len); 85 memcpy(qstring->string + qstring->length, str, len); 86 qstring->length += len; 87 qstring->string[qstring->length] = 0; 88 } 89 90 void qstring_append_int(QString *qstring, int64_t value) 91 { 92 char num[32]; 93 94 snprintf(num, sizeof(num), "%" PRId64, value); 95 qstring_append(qstring, num); 96 } 97 98 /** 99 * qstring_append_chr(): Append a C char to a QString 100 */ 101 void qstring_append_chr(QString *qstring, int c) 102 { 103 capacity_increase(qstring, 1); 104 qstring->string[qstring->length++] = c; 105 qstring->string[qstring->length] = 0; 106 } 107 108 /** 109 * qobject_to_qstring(): Convert a QObject to a QString 110 */ 111 QString *qobject_to_qstring(const QObject *obj) 112 { 113 if (!obj || qobject_type(obj) != QTYPE_QSTRING) { 114 return NULL; 115 } 116 return container_of(obj, QString, base); 117 } 118 119 /** 120 * qstring_get_str(): Return a pointer to the stored string 121 * 122 * NOTE: Should be used with caution, if the object is deallocated 123 * this pointer becomes invalid. 124 */ 125 const char *qstring_get_str(const QString *qstring) 126 { 127 return qstring->string; 128 } 129 130 /** 131 * qstring_destroy_obj(): Free all memory allocated by a QString 132 * object 133 */ 134 void qstring_destroy_obj(QObject *obj) 135 { 136 QString *qs; 137 138 assert(obj != NULL); 139 qs = qobject_to_qstring(obj); 140 g_free(qs->string); 141 g_free(qs); 142 } 143