Eduardo Habkost | c54d1c0 | 2014-10-01 17:34:37 -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-common.h" |
| 25 | #include "block/coroutine.h" |
| 26 | #include "migration/qemu-file.h" |
| 27 | |
| 28 | typedef struct QEMUFileStdio { |
| 29 | FILE *stdio_file; |
| 30 | QEMUFile *file; |
| 31 | } QEMUFileStdio; |
| 32 | |
| 33 | static int stdio_get_fd(void *opaque) |
| 34 | { |
| 35 | QEMUFileStdio *s = opaque; |
| 36 | |
| 37 | return fileno(s->stdio_file); |
| 38 | } |
| 39 | |
| 40 | static int stdio_put_buffer(void *opaque, const uint8_t *buf, int64_t pos, |
| 41 | int size) |
| 42 | { |
| 43 | QEMUFileStdio *s = opaque; |
| 44 | int res; |
| 45 | |
| 46 | res = fwrite(buf, 1, size, s->stdio_file); |
| 47 | |
| 48 | if (res != size) { |
| 49 | return -errno; |
| 50 | } |
| 51 | return res; |
| 52 | } |
| 53 | |
| 54 | static int stdio_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size) |
| 55 | { |
| 56 | QEMUFileStdio *s = opaque; |
| 57 | FILE *fp = s->stdio_file; |
| 58 | int bytes; |
| 59 | |
| 60 | for (;;) { |
| 61 | clearerr(fp); |
| 62 | bytes = fread(buf, 1, size, fp); |
| 63 | if (bytes != 0 || !ferror(fp)) { |
| 64 | break; |
| 65 | } |
| 66 | if (errno == EAGAIN) { |
| 67 | yield_until_fd_readable(fileno(fp)); |
| 68 | } else if (errno != EINTR) { |
| 69 | break; |
| 70 | } |
| 71 | } |
| 72 | return bytes; |
| 73 | } |
| 74 | |
| 75 | static int stdio_pclose(void *opaque) |
| 76 | { |
| 77 | QEMUFileStdio *s = opaque; |
| 78 | int ret; |
| 79 | ret = pclose(s->stdio_file); |
| 80 | if (ret == -1) { |
| 81 | ret = -errno; |
| 82 | } else if (!WIFEXITED(ret) || WEXITSTATUS(ret) != 0) { |
| 83 | /* close succeeded, but non-zero exit code: */ |
| 84 | ret = -EIO; /* fake errno value */ |
| 85 | } |
| 86 | g_free(s); |
| 87 | return ret; |
| 88 | } |
| 89 | |
| 90 | static int stdio_fclose(void *opaque) |
| 91 | { |
| 92 | QEMUFileStdio *s = opaque; |
| 93 | int ret = 0; |
| 94 | |
| 95 | if (qemu_file_is_writable(s->file)) { |
| 96 | int fd = fileno(s->stdio_file); |
| 97 | struct stat st; |
| 98 | |
| 99 | ret = fstat(fd, &st); |
| 100 | if (ret == 0 && S_ISREG(st.st_mode)) { |
| 101 | /* |
| 102 | * If the file handle is a regular file make sure the |
| 103 | * data is flushed to disk before signaling success. |
| 104 | */ |
| 105 | ret = fsync(fd); |
| 106 | if (ret != 0) { |
| 107 | ret = -errno; |
| 108 | return ret; |
| 109 | } |
| 110 | } |
| 111 | } |
| 112 | if (fclose(s->stdio_file) == EOF) { |
| 113 | ret = -errno; |
| 114 | } |
| 115 | g_free(s); |
| 116 | return ret; |
| 117 | } |
| 118 | |
| 119 | static const QEMUFileOps stdio_pipe_read_ops = { |
| 120 | .get_fd = stdio_get_fd, |
| 121 | .get_buffer = stdio_get_buffer, |
| 122 | .close = stdio_pclose |
| 123 | }; |
| 124 | |
| 125 | static const QEMUFileOps stdio_pipe_write_ops = { |
| 126 | .get_fd = stdio_get_fd, |
| 127 | .put_buffer = stdio_put_buffer, |
| 128 | .close = stdio_pclose |
| 129 | }; |
| 130 | |
| 131 | QEMUFile *qemu_popen_cmd(const char *command, const char *mode) |
| 132 | { |
| 133 | FILE *stdio_file; |
| 134 | QEMUFileStdio *s; |
| 135 | |
| 136 | if (mode == NULL || (mode[0] != 'r' && mode[0] != 'w') || mode[1] != 0) { |
| 137 | fprintf(stderr, "qemu_popen: Argument validity check failed\n"); |
| 138 | return NULL; |
| 139 | } |
| 140 | |
| 141 | stdio_file = popen(command, mode); |
| 142 | if (stdio_file == NULL) { |
| 143 | return NULL; |
| 144 | } |
| 145 | |
| 146 | s = g_malloc0(sizeof(QEMUFileStdio)); |
| 147 | |
| 148 | s->stdio_file = stdio_file; |
| 149 | |
| 150 | if (mode[0] == 'r') { |
| 151 | s->file = qemu_fopen_ops(s, &stdio_pipe_read_ops); |
| 152 | } else { |
| 153 | s->file = qemu_fopen_ops(s, &stdio_pipe_write_ops); |
| 154 | } |
| 155 | return s->file; |
| 156 | } |
| 157 | |
| 158 | static const QEMUFileOps stdio_file_read_ops = { |
| 159 | .get_fd = stdio_get_fd, |
| 160 | .get_buffer = stdio_get_buffer, |
| 161 | .close = stdio_fclose |
| 162 | }; |
| 163 | |
| 164 | static const QEMUFileOps stdio_file_write_ops = { |
| 165 | .get_fd = stdio_get_fd, |
| 166 | .put_buffer = stdio_put_buffer, |
| 167 | .close = stdio_fclose |
| 168 | }; |
| 169 | |
| 170 | QEMUFile *qemu_fopen(const char *filename, const char *mode) |
| 171 | { |
| 172 | QEMUFileStdio *s; |
| 173 | |
| 174 | if (qemu_file_mode_is_not_valid(mode)) { |
| 175 | return NULL; |
| 176 | } |
| 177 | |
| 178 | s = g_malloc0(sizeof(QEMUFileStdio)); |
| 179 | |
| 180 | s->stdio_file = fopen(filename, mode); |
| 181 | if (!s->stdio_file) { |
| 182 | goto fail; |
| 183 | } |
| 184 | |
| 185 | if (mode[0] == 'w') { |
| 186 | s->file = qemu_fopen_ops(s, &stdio_file_write_ops); |
| 187 | } else { |
| 188 | s->file = qemu_fopen_ops(s, &stdio_file_read_ops); |
| 189 | } |
| 190 | return s->file; |
| 191 | fail: |
| 192 | g_free(s); |
| 193 | return NULL; |
| 194 | } |