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
  27#include "qemu/osdep.h"
  28#include "qemu/module.h"
  29#include "chardev/char.h"
  30#include "qom/object.h"
  31
  32#define BUF_SIZE 32
  33
  34struct TestdevChardev {
  35    Chardev parent;
  36
  37    uint8_t in_buf[32];
  38    int in_buf_used;
  39};
  40typedef struct TestdevChardev TestdevChardev;
  41
  42#define TYPE_CHARDEV_TESTDEV "chardev-testdev"
  43DECLARE_INSTANCE_CHECKER(TestdevChardev, TESTDEV_CHARDEV,
  44                         TYPE_CHARDEV_TESTDEV)
  45
  46/* Try to interpret a whole incoming packet */
  47static int testdev_eat_packet(TestdevChardev *testdev)
  48{
  49    const uint8_t *cur = testdev->in_buf;
  50    int len = testdev->in_buf_used;
  51    uint8_t c;
  52    int arg;
  53
  54#define EAT(c) do { \
  55    if (!len--) {   \
  56        return 0;   \
  57    }               \
  58    c = *cur++;     \
  59} while (0)
  60
  61    EAT(c);
  62
  63    while (isspace(c)) {
  64        EAT(c);
  65    }
  66
  67    arg = 0;
  68    while (isdigit(c)) {
  69        arg = arg * 10 + c - '0';
  70        EAT(c);
  71    }
  72
  73    while (isspace(c)) {
  74        EAT(c);
  75    }
  76
  77    switch (c) {
  78    case 'q':
  79        exit((arg << 1) | 1);
  80        break;
  81    default:
  82        break;
  83    }
  84    return cur - testdev->in_buf;
  85}
  86
  87/* The other end is writing some data.  Store it and try to interpret */
  88static int testdev_chr_write(Chardev *chr, const uint8_t *buf, int len)
  89{
  90    TestdevChardev *testdev = TESTDEV_CHARDEV(chr);
  91    int tocopy, eaten, orig_len = len;
  92
  93    while (len) {
  94        /* Complete our buffer as much as possible */
  95        tocopy = MIN(len, BUF_SIZE - testdev->in_buf_used);
  96
  97        memcpy(testdev->in_buf + testdev->in_buf_used, buf, tocopy);
  98        testdev->in_buf_used += tocopy;
  99        buf += tocopy;
 100        len -= tocopy;
 101
 102        /* Interpret it as much as possible */
 103        while (testdev->in_buf_used > 0 &&
 104               (eaten = testdev_eat_packet(testdev)) > 0) {
 105            memmove(testdev->in_buf, testdev->in_buf + eaten,
 106                    testdev->in_buf_used - eaten);
 107            testdev->in_buf_used -= eaten;
 108        }
 109    }
 110    return orig_len;
 111}
 112
 113static void char_testdev_class_init(ObjectClass *oc, void *data)
 114{
 115    ChardevClass *cc = CHARDEV_CLASS(oc);
 116
 117    cc->chr_write = testdev_chr_write;
 118}
 119
 120static const TypeInfo char_testdev_type_info = {
 121    .name = TYPE_CHARDEV_TESTDEV,
 122    .parent = TYPE_CHARDEV,
 123    .instance_size = sizeof(TestdevChardev),
 124    .class_init = char_testdev_class_init,
 125};
 126
 127static void register_types(void)
 128{
 129    type_register_static(&char_testdev_type_info);
 130}
 131
 132type_init(register_types);
 133