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1 | 39b65c2e | aliguori | /*
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2 | 39b65c2e | aliguori | * QEMU buffered QEMUFile
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3 | 39b65c2e | aliguori | *
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4 | 39b65c2e | aliguori | * Copyright IBM, Corp. 2008
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5 | 39b65c2e | aliguori | *
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6 | 39b65c2e | aliguori | * Authors:
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7 | 39b65c2e | aliguori | * Anthony Liguori <aliguori@us.ibm.com>
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8 | 39b65c2e | aliguori | *
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9 | 39b65c2e | aliguori | * This work is licensed under the terms of the GNU GPL, version 2. See
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10 | 39b65c2e | aliguori | * the COPYING file in the top-level directory.
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11 | 39b65c2e | aliguori | *
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12 | 39b65c2e | aliguori | */
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13 | 39b65c2e | aliguori | |
14 | 39b65c2e | aliguori | #include "qemu-common.h" |
15 | 39b65c2e | aliguori | #include "hw/hw.h" |
16 | 39b65c2e | aliguori | #include "qemu-timer.h" |
17 | 39b65c2e | aliguori | #include "qemu-char.h" |
18 | 39b65c2e | aliguori | #include "buffered_file.h" |
19 | 39b65c2e | aliguori | |
20 | 39b65c2e | aliguori | //#define DEBUG_BUFFERED_FILE
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21 | 39b65c2e | aliguori | |
22 | 39b65c2e | aliguori | typedef struct QEMUFileBuffered |
23 | 39b65c2e | aliguori | { |
24 | 39b65c2e | aliguori | BufferedPutFunc *put_buffer; |
25 | 39b65c2e | aliguori | BufferedPutReadyFunc *put_ready; |
26 | 39b65c2e | aliguori | BufferedWaitForUnfreezeFunc *wait_for_unfreeze; |
27 | 39b65c2e | aliguori | BufferedCloseFunc *close; |
28 | 39b65c2e | aliguori | void *opaque;
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29 | 39b65c2e | aliguori | QEMUFile *file; |
30 | 39b65c2e | aliguori | int freeze_output;
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31 | 39b65c2e | aliguori | size_t bytes_xfer; |
32 | 39b65c2e | aliguori | size_t xfer_limit; |
33 | 39b65c2e | aliguori | uint8_t *buffer; |
34 | 39b65c2e | aliguori | size_t buffer_size; |
35 | 39b65c2e | aliguori | size_t buffer_capacity; |
36 | 39b65c2e | aliguori | QEMUTimer *timer; |
37 | 39b65c2e | aliguori | } QEMUFileBuffered; |
38 | 39b65c2e | aliguori | |
39 | 39b65c2e | aliguori | #ifdef DEBUG_BUFFERED_FILE
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40 | d0f2c4c6 | malc | #define DPRINTF(fmt, ...) \
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41 | 39b65c2e | aliguori | do { printf("buffered-file: " fmt, ## __VA_ARGS__); } while (0) |
42 | 39b65c2e | aliguori | #else
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43 | d0f2c4c6 | malc | #define DPRINTF(fmt, ...) \
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44 | 39b65c2e | aliguori | do { } while (0) |
45 | 39b65c2e | aliguori | #endif
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46 | 39b65c2e | aliguori | |
47 | 39b65c2e | aliguori | static void buffered_append(QEMUFileBuffered *s, |
48 | 39b65c2e | aliguori | const uint8_t *buf, size_t size)
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49 | 39b65c2e | aliguori | { |
50 | 39b65c2e | aliguori | if (size > (s->buffer_capacity - s->buffer_size)) {
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51 | 39b65c2e | aliguori | void *tmp;
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52 | 39b65c2e | aliguori | |
53 | d0f2c4c6 | malc | DPRINTF("increasing buffer capacity from %zu by %zu\n",
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54 | 39b65c2e | aliguori | s->buffer_capacity, size + 1024);
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55 | 39b65c2e | aliguori | |
56 | 39b65c2e | aliguori | s->buffer_capacity += size + 1024;
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57 | 39b65c2e | aliguori | |
58 | 7267c094 | Anthony Liguori | tmp = g_realloc(s->buffer, s->buffer_capacity); |
59 | 39b65c2e | aliguori | if (tmp == NULL) { |
60 | 39b65c2e | aliguori | fprintf(stderr, "qemu file buffer expansion failed\n");
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61 | 39b65c2e | aliguori | exit(1);
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62 | 39b65c2e | aliguori | } |
63 | 39b65c2e | aliguori | |
64 | 39b65c2e | aliguori | s->buffer = tmp; |
65 | 39b65c2e | aliguori | } |
66 | 39b65c2e | aliguori | |
67 | 39b65c2e | aliguori | memcpy(s->buffer + s->buffer_size, buf, size); |
68 | 39b65c2e | aliguori | s->buffer_size += size; |
69 | 39b65c2e | aliguori | } |
70 | 39b65c2e | aliguori | |
71 | 39b65c2e | aliguori | static void buffered_flush(QEMUFileBuffered *s) |
72 | 39b65c2e | aliguori | { |
73 | 39b65c2e | aliguori | size_t offset = 0;
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74 | 42802d47 | Juan Quintela | int error;
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75 | 39b65c2e | aliguori | |
76 | 42802d47 | Juan Quintela | error = qemu_file_get_error(s->file); |
77 | 42802d47 | Juan Quintela | if (error != 0) { |
78 | 42802d47 | Juan Quintela | DPRINTF("flush when error, bailing: %s\n", strerror(-error));
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79 | 39b65c2e | aliguori | return;
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80 | 39b65c2e | aliguori | } |
81 | 39b65c2e | aliguori | |
82 | d0f2c4c6 | malc | DPRINTF("flushing %zu byte(s) of data\n", s->buffer_size);
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83 | 39b65c2e | aliguori | |
84 | 39b65c2e | aliguori | while (offset < s->buffer_size) {
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85 | 39b65c2e | aliguori | ssize_t ret; |
86 | 39b65c2e | aliguori | |
87 | 39b65c2e | aliguori | ret = s->put_buffer(s->opaque, s->buffer + offset, |
88 | 39b65c2e | aliguori | s->buffer_size - offset); |
89 | 39b65c2e | aliguori | if (ret == -EAGAIN) {
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90 | d0f2c4c6 | malc | DPRINTF("backend not ready, freezing\n");
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91 | 39b65c2e | aliguori | s->freeze_output = 1;
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92 | 39b65c2e | aliguori | break;
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93 | 39b65c2e | aliguori | } |
94 | 39b65c2e | aliguori | |
95 | 39b65c2e | aliguori | if (ret <= 0) { |
96 | d0f2c4c6 | malc | DPRINTF("error flushing data, %zd\n", ret);
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97 | dcd1d224 | Juan Quintela | qemu_file_set_error(s->file, ret); |
98 | 39b65c2e | aliguori | break;
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99 | 39b65c2e | aliguori | } else {
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100 | d0f2c4c6 | malc | DPRINTF("flushed %zd byte(s)\n", ret);
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101 | 39b65c2e | aliguori | offset += ret; |
102 | 39b65c2e | aliguori | } |
103 | 39b65c2e | aliguori | } |
104 | 39b65c2e | aliguori | |
105 | d0f2c4c6 | malc | DPRINTF("flushed %zu of %zu byte(s)\n", offset, s->buffer_size);
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106 | 39b65c2e | aliguori | memmove(s->buffer, s->buffer + offset, s->buffer_size - offset); |
107 | 39b65c2e | aliguori | s->buffer_size -= offset; |
108 | 39b65c2e | aliguori | } |
109 | 39b65c2e | aliguori | |
110 | 39b65c2e | aliguori | static int buffered_put_buffer(void *opaque, const uint8_t *buf, int64_t pos, int size) |
111 | 39b65c2e | aliguori | { |
112 | 39b65c2e | aliguori | QEMUFileBuffered *s = opaque; |
113 | 42802d47 | Juan Quintela | int offset = 0, error; |
114 | 39b65c2e | aliguori | ssize_t ret; |
115 | 39b65c2e | aliguori | |
116 | d0f2c4c6 | malc | DPRINTF("putting %d bytes at %" PRId64 "\n", size, pos); |
117 | 39b65c2e | aliguori | |
118 | 42802d47 | Juan Quintela | error = qemu_file_get_error(s->file); |
119 | 42802d47 | Juan Quintela | if (error) {
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120 | 42802d47 | Juan Quintela | DPRINTF("flush when error, bailing: %s\n", strerror(-error));
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121 | 42802d47 | Juan Quintela | return error;
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122 | 39b65c2e | aliguori | } |
123 | 39b65c2e | aliguori | |
124 | d0f2c4c6 | malc | DPRINTF("unfreezing output\n");
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125 | 39b65c2e | aliguori | s->freeze_output = 0;
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126 | 39b65c2e | aliguori | |
127 | 39b65c2e | aliguori | buffered_flush(s); |
128 | 39b65c2e | aliguori | |
129 | 39b65c2e | aliguori | while (!s->freeze_output && offset < size) {
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130 | 39b65c2e | aliguori | if (s->bytes_xfer > s->xfer_limit) {
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131 | d0f2c4c6 | malc | DPRINTF("transfer limit exceeded when putting\n");
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132 | 39b65c2e | aliguori | break;
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133 | 39b65c2e | aliguori | } |
134 | 39b65c2e | aliguori | |
135 | 39b65c2e | aliguori | ret = s->put_buffer(s->opaque, buf + offset, size - offset); |
136 | 39b65c2e | aliguori | if (ret == -EAGAIN) {
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137 | d0f2c4c6 | malc | DPRINTF("backend not ready, freezing\n");
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138 | 39b65c2e | aliguori | s->freeze_output = 1;
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139 | 39b65c2e | aliguori | break;
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140 | 39b65c2e | aliguori | } |
141 | 39b65c2e | aliguori | |
142 | 39b65c2e | aliguori | if (ret <= 0) { |
143 | d0f2c4c6 | malc | DPRINTF("error putting\n");
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144 | dcd1d224 | Juan Quintela | qemu_file_set_error(s->file, ret); |
145 | 39b65c2e | aliguori | offset = -EINVAL; |
146 | 39b65c2e | aliguori | break;
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147 | 39b65c2e | aliguori | } |
148 | 39b65c2e | aliguori | |
149 | d0f2c4c6 | malc | DPRINTF("put %zd byte(s)\n", ret);
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150 | 39b65c2e | aliguori | offset += ret; |
151 | 39b65c2e | aliguori | s->bytes_xfer += ret; |
152 | 39b65c2e | aliguori | } |
153 | 39b65c2e | aliguori | |
154 | 39b65c2e | aliguori | if (offset >= 0) { |
155 | d0f2c4c6 | malc | DPRINTF("buffering %d bytes\n", size - offset);
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156 | 39b65c2e | aliguori | buffered_append(s, buf + offset, size - offset); |
157 | 39b65c2e | aliguori | offset = size; |
158 | 39b65c2e | aliguori | } |
159 | 39b65c2e | aliguori | |
160 | 5e77aaa0 | Avi Kivity | if (pos == 0 && size == 0) { |
161 | 5e77aaa0 | Avi Kivity | DPRINTF("file is ready\n");
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162 | 5e77aaa0 | Avi Kivity | if (s->bytes_xfer <= s->xfer_limit) {
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163 | 5e77aaa0 | Avi Kivity | DPRINTF("notifying client\n");
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164 | 5e77aaa0 | Avi Kivity | s->put_ready(s->opaque); |
165 | 5e77aaa0 | Avi Kivity | } |
166 | 5e77aaa0 | Avi Kivity | } |
167 | 5e77aaa0 | Avi Kivity | |
168 | 39b65c2e | aliguori | return offset;
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169 | 39b65c2e | aliguori | } |
170 | 39b65c2e | aliguori | |
171 | 39b65c2e | aliguori | static int buffered_close(void *opaque) |
172 | 39b65c2e | aliguori | { |
173 | 39b65c2e | aliguori | QEMUFileBuffered *s = opaque; |
174 | 39b65c2e | aliguori | int ret;
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175 | 39b65c2e | aliguori | |
176 | d0f2c4c6 | malc | DPRINTF("closing\n");
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177 | 39b65c2e | aliguori | |
178 | 624b9cc2 | Juan Quintela | while (!qemu_file_get_error(s->file) && s->buffer_size) {
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179 | 39b65c2e | aliguori | buffered_flush(s); |
180 | 39b65c2e | aliguori | if (s->freeze_output)
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181 | db448a08 | Juan Quintela | s->wait_for_unfreeze(s->opaque); |
182 | 39b65c2e | aliguori | } |
183 | 39b65c2e | aliguori | |
184 | 39b65c2e | aliguori | ret = s->close(s->opaque); |
185 | 39b65c2e | aliguori | |
186 | 39b65c2e | aliguori | qemu_del_timer(s->timer); |
187 | 39b65c2e | aliguori | qemu_free_timer(s->timer); |
188 | 7267c094 | Anthony Liguori | g_free(s->buffer); |
189 | 7267c094 | Anthony Liguori | g_free(s); |
190 | 39b65c2e | aliguori | |
191 | 39b65c2e | aliguori | return ret;
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192 | 39b65c2e | aliguori | } |
193 | 39b65c2e | aliguori | |
194 | 4fc7d819 | Juan Quintela | /*
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195 | 4fc7d819 | Juan Quintela | * The meaning of the return values is:
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196 | 4fc7d819 | Juan Quintela | * 0: We can continue sending
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197 | 4fc7d819 | Juan Quintela | * 1: Time to stop
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198 | 42802d47 | Juan Quintela | * negative: There has been an error
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199 | 4fc7d819 | Juan Quintela | */
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200 | 39b65c2e | aliguori | static int buffered_rate_limit(void *opaque) |
201 | 39b65c2e | aliguori | { |
202 | 39b65c2e | aliguori | QEMUFileBuffered *s = opaque; |
203 | 42802d47 | Juan Quintela | int ret;
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204 | 39b65c2e | aliguori | |
205 | 42802d47 | Juan Quintela | ret = qemu_file_get_error(s->file); |
206 | 42802d47 | Juan Quintela | if (ret) {
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207 | 42802d47 | Juan Quintela | return ret;
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208 | 4fc7d819 | Juan Quintela | } |
209 | 39b65c2e | aliguori | if (s->freeze_output)
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210 | 39b65c2e | aliguori | return 1; |
211 | 39b65c2e | aliguori | |
212 | 39b65c2e | aliguori | if (s->bytes_xfer > s->xfer_limit)
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213 | 39b65c2e | aliguori | return 1; |
214 | 39b65c2e | aliguori | |
215 | 39b65c2e | aliguori | return 0; |
216 | 39b65c2e | aliguori | } |
217 | 39b65c2e | aliguori | |
218 | 3d002df3 | Michael S. Tsirkin | static int64_t buffered_set_rate_limit(void *opaque, int64_t new_rate) |
219 | 19629537 | Glauber Costa | { |
220 | 19629537 | Glauber Costa | QEMUFileBuffered *s = opaque; |
221 | 624b9cc2 | Juan Quintela | if (qemu_file_get_error(s->file)) {
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222 | 19629537 | Glauber Costa | goto out;
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223 | 624b9cc2 | Juan Quintela | } |
224 | 3d002df3 | Michael S. Tsirkin | if (new_rate > SIZE_MAX) {
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225 | 3d002df3 | Michael S. Tsirkin | new_rate = SIZE_MAX; |
226 | 3d002df3 | Michael S. Tsirkin | } |
227 | 3d002df3 | Michael S. Tsirkin | |
228 | 19629537 | Glauber Costa | s->xfer_limit = new_rate / 10;
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229 | 19629537 | Glauber Costa | |
230 | 19629537 | Glauber Costa | out:
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231 | 19629537 | Glauber Costa | return s->xfer_limit;
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232 | 19629537 | Glauber Costa | } |
233 | 19629537 | Glauber Costa | |
234 | 3d002df3 | Michael S. Tsirkin | static int64_t buffered_get_rate_limit(void *opaque) |
235 | c163b5ca | lirans@il.ibm.com | { |
236 | c163b5ca | lirans@il.ibm.com | QEMUFileBuffered *s = opaque; |
237 | c163b5ca | lirans@il.ibm.com | |
238 | c163b5ca | lirans@il.ibm.com | return s->xfer_limit;
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239 | c163b5ca | lirans@il.ibm.com | } |
240 | c163b5ca | lirans@il.ibm.com | |
241 | 39b65c2e | aliguori | static void buffered_rate_tick(void *opaque) |
242 | 39b65c2e | aliguori | { |
243 | 39b65c2e | aliguori | QEMUFileBuffered *s = opaque; |
244 | 39b65c2e | aliguori | |
245 | 624b9cc2 | Juan Quintela | if (qemu_file_get_error(s->file)) {
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246 | e447b1a6 | Marcelo Tosatti | buffered_close(s); |
247 | 39b65c2e | aliguori | return;
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248 | e447b1a6 | Marcelo Tosatti | } |
249 | 39b65c2e | aliguori | |
250 | 7bd427d8 | Paolo Bonzini | qemu_mod_timer(s->timer, qemu_get_clock_ms(rt_clock) + 100);
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251 | 39b65c2e | aliguori | |
252 | 39b65c2e | aliguori | if (s->freeze_output)
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253 | 39b65c2e | aliguori | return;
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254 | 39b65c2e | aliguori | |
255 | 39b65c2e | aliguori | s->bytes_xfer = 0;
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256 | 39b65c2e | aliguori | |
257 | 39b65c2e | aliguori | buffered_flush(s); |
258 | 39b65c2e | aliguori | |
259 | 39b65c2e | aliguori | /* Add some checks around this */
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260 | 39b65c2e | aliguori | s->put_ready(s->opaque); |
261 | 39b65c2e | aliguori | } |
262 | 39b65c2e | aliguori | |
263 | 39b65c2e | aliguori | QEMUFile *qemu_fopen_ops_buffered(void *opaque,
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264 | 39b65c2e | aliguori | size_t bytes_per_sec, |
265 | 39b65c2e | aliguori | BufferedPutFunc *put_buffer, |
266 | 39b65c2e | aliguori | BufferedPutReadyFunc *put_ready, |
267 | 39b65c2e | aliguori | BufferedWaitForUnfreezeFunc *wait_for_unfreeze, |
268 | 39b65c2e | aliguori | BufferedCloseFunc *close) |
269 | 39b65c2e | aliguori | { |
270 | 39b65c2e | aliguori | QEMUFileBuffered *s; |
271 | 39b65c2e | aliguori | |
272 | 7267c094 | Anthony Liguori | s = g_malloc0(sizeof(*s));
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273 | 39b65c2e | aliguori | |
274 | 39b65c2e | aliguori | s->opaque = opaque; |
275 | 39b65c2e | aliguori | s->xfer_limit = bytes_per_sec / 10;
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276 | 39b65c2e | aliguori | s->put_buffer = put_buffer; |
277 | 39b65c2e | aliguori | s->put_ready = put_ready; |
278 | 39b65c2e | aliguori | s->wait_for_unfreeze = wait_for_unfreeze; |
279 | 39b65c2e | aliguori | s->close = close; |
280 | 39b65c2e | aliguori | |
281 | 39b65c2e | aliguori | s->file = qemu_fopen_ops(s, buffered_put_buffer, NULL,
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282 | 19629537 | Glauber Costa | buffered_close, buffered_rate_limit, |
283 | c163b5ca | lirans@il.ibm.com | buffered_set_rate_limit, |
284 | c163b5ca | lirans@il.ibm.com | buffered_get_rate_limit); |
285 | 39b65c2e | aliguori | |
286 | 7bd427d8 | Paolo Bonzini | s->timer = qemu_new_timer_ms(rt_clock, buffered_rate_tick, s); |
287 | 39b65c2e | aliguori | |
288 | 7bd427d8 | Paolo Bonzini | qemu_mod_timer(s->timer, qemu_get_clock_ms(rt_clock) + 100);
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289 | 39b65c2e | aliguori | |
290 | 39b65c2e | aliguori | return s->file;
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291 | 39b65c2e | aliguori | } |