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