diff options
Diffstat (limited to 'migration/qemu-file-stdio.c')
| -rw-r--r-- | migration/qemu-file-stdio.c | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/migration/qemu-file-stdio.c b/migration/qemu-file-stdio.c new file mode 100644 index 0000000000..285068b303 --- /dev/null +++ b/migration/qemu-file-stdio.c @@ -0,0 +1,194 @@ +/* + * QEMU System Emulator + * + * Copyright (c) 2003-2008 Fabrice Bellard + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ +#include "qemu-common.h" +#include "block/coroutine.h" +#include "migration/qemu-file.h" + +typedef struct QEMUFileStdio { + FILE *stdio_file; + QEMUFile *file; +} QEMUFileStdio; + +static int stdio_get_fd(void *opaque) +{ + QEMUFileStdio *s = opaque; + + return fileno(s->stdio_file); +} + +static int stdio_put_buffer(void *opaque, const uint8_t *buf, int64_t pos, + int size) +{ + QEMUFileStdio *s = opaque; + int res; + + res = fwrite(buf, 1, size, s->stdio_file); + + if (res != size) { + return -errno; + } + return res; +} + +static int stdio_get_buffer(void *opaque, uint8_t *buf, int64_t pos, int size) +{ + QEMUFileStdio *s = opaque; + FILE *fp = s->stdio_file; + int bytes; + + for (;;) { + clearerr(fp); + bytes = fread(buf, 1, size, fp); + if (bytes != 0 || !ferror(fp)) { + break; + } + if (errno == EAGAIN) { + yield_until_fd_readable(fileno(fp)); + } else if (errno != EINTR) { + break; + } + } + return bytes; +} + +static int stdio_pclose(void *opaque) +{ + QEMUFileStdio *s = opaque; + int ret; + ret = pclose(s->stdio_file); + if (ret == -1) { + ret = -errno; + } else if (!WIFEXITED(ret) || WEXITSTATUS(ret) != 0) { + /* close succeeded, but non-zero exit code: */ + ret = -EIO; /* fake errno value */ + } + g_free(s); + return ret; +} + +static int stdio_fclose(void *opaque) +{ + QEMUFileStdio *s = opaque; + int ret = 0; + + if (qemu_file_is_writable(s->file)) { + int fd = fileno(s->stdio_file); + struct stat st; + + ret = fstat(fd, &st); + if (ret == 0 && S_ISREG(st.st_mode)) { + /* + * If the file handle is a regular file make sure the + * data is flushed to disk before signaling success. + */ + ret = fsync(fd); + if (ret != 0) { + ret = -errno; + return ret; + } + } + } + if (fclose(s->stdio_file) == EOF) { + ret = -errno; + } + g_free(s); + return ret; +} + +static const QEMUFileOps stdio_pipe_read_ops = { + .get_fd = stdio_get_fd, + .get_buffer = stdio_get_buffer, + .close = stdio_pclose +}; + +static const QEMUFileOps stdio_pipe_write_ops = { + .get_fd = stdio_get_fd, + .put_buffer = stdio_put_buffer, + .close = stdio_pclose +}; + +QEMUFile *qemu_popen_cmd(const char *command, const char *mode) +{ + FILE *stdio_file; + QEMUFileStdio *s; + + if (mode == NULL || (mode[0] != 'r' && mode[0] != 'w') || mode[1] != 0) { + fprintf(stderr, "qemu_popen: Argument validity check failed\n"); + return NULL; + } + + stdio_file = popen(command, mode); + if (stdio_file == NULL) { + return NULL; + } + + s = g_malloc0(sizeof(QEMUFileStdio)); + + s->stdio_file = stdio_file; + + if (mode[0] == 'r') { + s->file = qemu_fopen_ops(s, &stdio_pipe_read_ops); + } else { + s->file = qemu_fopen_ops(s, &stdio_pipe_write_ops); + } + return s->file; +} + +static const QEMUFileOps stdio_file_read_ops = { + .get_fd = stdio_get_fd, + .get_buffer = stdio_get_buffer, + .close = stdio_fclose +}; + +static const QEMUFileOps stdio_file_write_ops = { + .get_fd = stdio_get_fd, + .put_buffer = stdio_put_buffer, + .close = stdio_fclose +}; + +QEMUFile *qemu_fopen(const char *filename, const char *mode) +{ + QEMUFileStdio *s; + + if (qemu_file_mode_is_not_valid(mode)) { + return NULL; + } + + s = g_malloc0(sizeof(QEMUFileStdio)); + + s->stdio_file = fopen(filename, mode); + if (!s->stdio_file) { + goto fail; + } + + if (mode[0] == 'w') { + s->file = qemu_fopen_ops(s, &stdio_file_write_ops); + } else { + s->file = qemu_fopen_ops(s, &stdio_file_read_ops); + } + return s->file; +fail: + g_free(s); + return NULL; +} |