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_from_substr(): Create a new QString from a C string substring
  36 *
  37 * Return string reference
  38 */
  39QString *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 */
  62QString *qstring_from_str(const char *str)
  63{
  64    return qstring_from_substr(str, 0, strlen(str) - 1);
  65}
  66
  67static 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 */
  79void 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
  89void 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 */
 100void 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 */
 110QString *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 */
 124const 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 */
 133static 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