LXR qemu/chardev/testdev.c

   1/*
   2 * QEMU Char Device for testsuite control
   3 *
   4 * Copyright (c) 2014 Red Hat, Inc.
   5 *
   6 * Author: Paolo Bonzini <pbonzini@redhat.com>
   7 *
   8 * Permission is hereby granted, free of charge, to any person obtaining a copy
   9 * of this software and associated documentation files (the "Software"), to deal
  10 * in the Software without restriction, including without limitation the rights
  11 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  12 * copies of the Software, and to permit persons to whom the Software is
  13 * furnished to do so, subject to the following conditions:
  14 *
  15 * The above copyright notice and this permission notice shall be included in
  16 * all copies or substantial portions of the Software.
  17 *
  18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  21 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  22 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  23 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  24 * THE SOFTWARE.
  25 */
  26#include "qemu/osdep.h"
  27#include "qemu-common.h"
  28#include "chardev/char.h"
  29
  30#define BUF_SIZE 32
  31
  32typedef struct {
  33    Chardev parent;
  34
  35    uint8_t in_buf[32];
  36    int in_buf_used;
  37} TestdevChardev;
  38
  39#define TYPE_CHARDEV_TESTDEV "chardev-testdev"
  40#define TESTDEV_CHARDEV(obj)                                    \
  41    OBJECT_CHECK(TestdevChardev, (obj), TYPE_CHARDEV_TESTDEV)
  42
  43/* Try to interpret a whole incoming packet */
  44static int testdev_eat_packet(TestdevChardev *testdev)
  45{
  46    const uint8_t *cur = testdev->in_buf;
  47    int len = testdev->in_buf_used;
  48    uint8_t c;
  49    int arg;
  50
  51#define EAT(c) do { \
  52    if (!len--) {   \
  53        return 0;   \
  54    }               \
  55    c = *cur++;     \
  56} while (0)
  57
  58    EAT(c);
  59
  60    while (isspace(c)) {
  61        EAT(c);
  62    }
  63
  64    arg = 0;
  65    while (isdigit(c)) {
  66        arg = arg * 10 + c - '0';
  67        EAT(c);
  68    }
  69
  70    while (isspace(c)) {
  71        EAT(c);
  72    }
  73
  74    switch (c) {
  75    case 'q':
  76        exit((arg << 1) | 1);
  77        break;
  78    default:
  79        break;
  80    }
  81    return cur - testdev->in_buf;
  82}
  83
  84/* The other end is writing some data.  Store it and try to interpret */
  85static int testdev_chr_write(Chardev *chr, const uint8_t *buf, int len)
  86{
  87    TestdevChardev *testdev = TESTDEV_CHARDEV(chr);
  88    int tocopy, eaten, orig_len = len;
  89
  90    while (len) {
  91        /* Complete our buffer as much as possible */
  92        tocopy = MIN(len, BUF_SIZE - testdev->in_buf_used);
  93
  94        memcpy(testdev->in_buf + testdev->in_buf_used, buf, tocopy);
  95        testdev->in_buf_used += tocopy;
  96        buf += tocopy;
  97        len -= tocopy;
  98
  99        /* Interpret it as much as possible */
 100        while (testdev->in_buf_used > 0 &&
 101               (eaten = testdev_eat_packet(testdev)) > 0) {
 102            memmove(testdev->in_buf, testdev->in_buf + eaten,
 103                    testdev->in_buf_used - eaten);
 104            testdev->in_buf_used -= eaten;
 105        }
 106    }
 107    return orig_len;
 108}
 109
 110static void char_testdev_class_init(ObjectClass *oc, void *data)
 111{
 112    ChardevClass *cc = CHARDEV_CLASS(oc);
 113
 114    cc->chr_write = testdev_chr_write;
 115}
 116
 117static const TypeInfo char_testdev_type_info = {
 118    .name = TYPE_CHARDEV_TESTDEV,
 119    .parent = TYPE_CHARDEV,
 120    .instance_size = sizeof(TestdevChardev),
 121    .class_init = char_testdev_class_init,
 122};
 123
 124static void register_types(void)
 125{
 126    type_register_static(&char_testdev_type_info);
 127}
 128
 129type_init(register_types);
 130