LXR qemu/qobject/qstring.c

   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
  17static void qstring_destroy_obj(QObject *obj);
  18
  19static 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 */
  29QString *qstring_new(void)
  30{
  31    return qstring_from_str("");
  32}
  33
  34/**
  35 * qstring_get_length(): Get the length of a QString
  36 */
  37size_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 */
  47QString *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 */
  70QString *qstring_from_str(const char *str)
  71{
  72    return qstring_from_substr(str, 0, strlen(str) - 1);
  73}
  74
  75static 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 */
  87void 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
  97void 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 */
 108void 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 */
 118QString *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 */
 132const 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 */
 141static 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