Marc-André Lureau | bf51f62 | 2016-12-12 16:32:18 +0300 | [diff] [blame] | 1 | /* |
| 2 | * QEMU System Emulator |
| 3 | * |
| 4 | * Copyright (c) 2003-2008 Fabrice Bellard |
| 5 | * |
| 6 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 7 | * of this software and associated documentation files (the "Software"), to deal |
| 8 | * in the Software without restriction, including without limitation the rights |
| 9 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| 10 | * copies of the Software, and to permit persons to whom the Software is |
| 11 | * furnished to do so, subject to the following conditions: |
| 12 | * |
| 13 | * The above copyright notice and this permission notice shall be included in |
| 14 | * all copies or substantial portions of the Software. |
| 15 | * |
| 16 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 17 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 18 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| 19 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 20 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 21 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| 22 | * THE SOFTWARE. |
| 23 | */ |
| 24 | #include "qemu/osdep.h" |
| 25 | #include "sysemu/char.h" |
| 26 | #include "qmp-commands.h" |
| 27 | #include "qemu/base64.h" |
| 28 | |
| 29 | /* Ring buffer chardev */ |
| 30 | |
| 31 | typedef struct { |
| 32 | Chardev parent; |
| 33 | size_t size; |
| 34 | size_t prod; |
| 35 | size_t cons; |
| 36 | uint8_t *cbuf; |
| 37 | } RingBufChardev; |
| 38 | |
| 39 | #define RINGBUF_CHARDEV(obj) \ |
| 40 | OBJECT_CHECK(RingBufChardev, (obj), TYPE_CHARDEV_RINGBUF) |
| 41 | |
| 42 | static size_t ringbuf_count(const Chardev *chr) |
| 43 | { |
| 44 | const RingBufChardev *d = RINGBUF_CHARDEV(chr); |
| 45 | |
| 46 | return d->prod - d->cons; |
| 47 | } |
| 48 | |
| 49 | static int ringbuf_chr_write(Chardev *chr, const uint8_t *buf, int len) |
| 50 | { |
| 51 | RingBufChardev *d = RINGBUF_CHARDEV(chr); |
| 52 | int i; |
| 53 | |
| 54 | if (!buf || (len < 0)) { |
| 55 | return -1; |
| 56 | } |
| 57 | |
| 58 | for (i = 0; i < len; i++) { |
| 59 | d->cbuf[d->prod++ & (d->size - 1)] = buf[i]; |
| 60 | if (d->prod - d->cons > d->size) { |
| 61 | d->cons = d->prod - d->size; |
| 62 | } |
| 63 | } |
| 64 | |
| 65 | return len; |
| 66 | } |
| 67 | |
| 68 | static int ringbuf_chr_read(Chardev *chr, uint8_t *buf, int len) |
| 69 | { |
| 70 | RingBufChardev *d = RINGBUF_CHARDEV(chr); |
| 71 | int i; |
| 72 | |
| 73 | qemu_mutex_lock(&chr->chr_write_lock); |
| 74 | for (i = 0; i < len && d->cons != d->prod; i++) { |
| 75 | buf[i] = d->cbuf[d->cons++ & (d->size - 1)]; |
| 76 | } |
| 77 | qemu_mutex_unlock(&chr->chr_write_lock); |
| 78 | |
| 79 | return i; |
| 80 | } |
| 81 | |
| 82 | static void char_ringbuf_finalize(Object *obj) |
| 83 | { |
| 84 | RingBufChardev *d = RINGBUF_CHARDEV(obj); |
| 85 | |
| 86 | g_free(d->cbuf); |
| 87 | } |
| 88 | |
| 89 | static void qemu_chr_open_ringbuf(Chardev *chr, |
| 90 | ChardevBackend *backend, |
| 91 | bool *be_opened, |
| 92 | Error **errp) |
| 93 | { |
| 94 | ChardevRingbuf *opts = backend->u.ringbuf.data; |
| 95 | RingBufChardev *d = RINGBUF_CHARDEV(chr); |
| 96 | |
| 97 | d->size = opts->has_size ? opts->size : 65536; |
| 98 | |
| 99 | /* The size must be power of 2 */ |
| 100 | if (d->size & (d->size - 1)) { |
| 101 | error_setg(errp, "size of ringbuf chardev must be power of two"); |
| 102 | return; |
| 103 | } |
| 104 | |
| 105 | d->prod = 0; |
| 106 | d->cons = 0; |
| 107 | d->cbuf = g_malloc0(d->size); |
| 108 | } |
| 109 | |
| 110 | void qmp_ringbuf_write(const char *device, const char *data, |
| 111 | bool has_format, enum DataFormat format, |
| 112 | Error **errp) |
| 113 | { |
| 114 | Chardev *chr; |
| 115 | const uint8_t *write_data; |
| 116 | int ret; |
| 117 | gsize write_count; |
| 118 | |
| 119 | chr = qemu_chr_find(device); |
| 120 | if (!chr) { |
| 121 | error_setg(errp, "Device '%s' not found", device); |
| 122 | return; |
| 123 | } |
| 124 | |
| 125 | if (!CHARDEV_IS_RINGBUF(chr)) { |
| 126 | error_setg(errp, "%s is not a ringbuf device", device); |
| 127 | return; |
| 128 | } |
| 129 | |
| 130 | if (has_format && (format == DATA_FORMAT_BASE64)) { |
| 131 | write_data = qbase64_decode(data, -1, |
| 132 | &write_count, |
| 133 | errp); |
| 134 | if (!write_data) { |
| 135 | return; |
| 136 | } |
| 137 | } else { |
| 138 | write_data = (uint8_t *)data; |
| 139 | write_count = strlen(data); |
| 140 | } |
| 141 | |
| 142 | ret = ringbuf_chr_write(chr, write_data, write_count); |
| 143 | |
| 144 | if (write_data != (uint8_t *)data) { |
| 145 | g_free((void *)write_data); |
| 146 | } |
| 147 | |
| 148 | if (ret < 0) { |
| 149 | error_setg(errp, "Failed to write to device %s", device); |
| 150 | return; |
| 151 | } |
| 152 | } |
| 153 | |
| 154 | char *qmp_ringbuf_read(const char *device, int64_t size, |
| 155 | bool has_format, enum DataFormat format, |
| 156 | Error **errp) |
| 157 | { |
| 158 | Chardev *chr; |
| 159 | uint8_t *read_data; |
| 160 | size_t count; |
| 161 | char *data; |
| 162 | |
| 163 | chr = qemu_chr_find(device); |
| 164 | if (!chr) { |
| 165 | error_setg(errp, "Device '%s' not found", device); |
| 166 | return NULL; |
| 167 | } |
| 168 | |
| 169 | if (!CHARDEV_IS_RINGBUF(chr)) { |
| 170 | error_setg(errp, "%s is not a ringbuf device", device); |
| 171 | return NULL; |
| 172 | } |
| 173 | |
| 174 | if (size <= 0) { |
| 175 | error_setg(errp, "size must be greater than zero"); |
| 176 | return NULL; |
| 177 | } |
| 178 | |
| 179 | count = ringbuf_count(chr); |
| 180 | size = size > count ? count : size; |
| 181 | read_data = g_malloc(size + 1); |
| 182 | |
| 183 | ringbuf_chr_read(chr, read_data, size); |
| 184 | |
| 185 | if (has_format && (format == DATA_FORMAT_BASE64)) { |
| 186 | data = g_base64_encode(read_data, size); |
| 187 | g_free(read_data); |
| 188 | } else { |
| 189 | /* |
| 190 | * FIXME should read only complete, valid UTF-8 characters up |
| 191 | * to @size bytes. Invalid sequences should be replaced by a |
| 192 | * suitable replacement character. Except when (and only |
| 193 | * when) ring buffer lost characters since last read, initial |
| 194 | * continuation characters should be dropped. |
| 195 | */ |
| 196 | read_data[size] = 0; |
| 197 | data = (char *)read_data; |
| 198 | } |
| 199 | |
| 200 | return data; |
| 201 | } |
| 202 | |
| 203 | static void qemu_chr_parse_ringbuf(QemuOpts *opts, ChardevBackend *backend, |
| 204 | Error **errp) |
| 205 | { |
| 206 | int val; |
| 207 | ChardevRingbuf *ringbuf; |
| 208 | |
| 209 | backend->type = CHARDEV_BACKEND_KIND_RINGBUF; |
| 210 | ringbuf = backend->u.ringbuf.data = g_new0(ChardevRingbuf, 1); |
| 211 | qemu_chr_parse_common(opts, qapi_ChardevRingbuf_base(ringbuf)); |
| 212 | |
| 213 | val = qemu_opt_get_size(opts, "size", 0); |
| 214 | if (val != 0) { |
| 215 | ringbuf->has_size = true; |
| 216 | ringbuf->size = val; |
| 217 | } |
| 218 | } |
| 219 | |
| 220 | static void char_ringbuf_class_init(ObjectClass *oc, void *data) |
| 221 | { |
| 222 | ChardevClass *cc = CHARDEV_CLASS(oc); |
| 223 | |
| 224 | cc->parse = qemu_chr_parse_ringbuf; |
| 225 | cc->open = qemu_chr_open_ringbuf; |
| 226 | cc->chr_write = ringbuf_chr_write; |
| 227 | } |
| 228 | |
| 229 | static const TypeInfo char_ringbuf_type_info = { |
| 230 | .name = TYPE_CHARDEV_RINGBUF, |
| 231 | .parent = TYPE_CHARDEV, |
| 232 | .class_init = char_ringbuf_class_init, |
| 233 | .instance_size = sizeof(RingBufChardev), |
| 234 | .instance_finalize = char_ringbuf_finalize, |
| 235 | }; |
| 236 | |
| 237 | /* Bug-compatibility: */ |
| 238 | static const TypeInfo char_memory_type_info = { |
| 239 | .name = TYPE_CHARDEV_MEMORY, |
| 240 | .parent = TYPE_CHARDEV_RINGBUF, |
| 241 | }; |
| 242 | |
| 243 | static void register_types(void) |
| 244 | { |
| 245 | type_register_static(&char_ringbuf_type_info); |
| 246 | type_register_static(&char_memory_type_info); |
| 247 | } |
| 248 | |
| 249 | type_init(register_types); |