diff options
| -rw-r--r-- | qga/commands-posix.c | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/qga/commands-posix.c b/qga/commands-posix.c index 0ebd47336a..cf1d7ec8c0 100644 --- a/qga/commands-posix.c +++ b/qga/commands-posix.c @@ -216,9 +216,16 @@ void qmp_guest_set_time(bool has_time, int64_t time_ns, Error **errp) } } +typedef enum { + RW_STATE_NEW, + RW_STATE_READING, + RW_STATE_WRITING, +} RwState; + typedef struct GuestFileHandle { uint64_t id; FILE *fh; + RwState state; QTAILQ_ENTRY(GuestFileHandle) next; } GuestFileHandle; @@ -460,6 +467,17 @@ struct GuestFileRead *qmp_guest_file_read(int64_t handle, bool has_count, } fh = gfh->fh; + + /* explicitly flush when switching from writing to reading */ + if (gfh->state == RW_STATE_WRITING) { + int ret = fflush(fh); + if (ret == EOF) { + error_setg_errno(errp, errno, "failed to flush file"); + return NULL; + } + gfh->state = RW_STATE_NEW; + } + buf = g_malloc0(count+1); read_count = fread(buf, 1, count, fh); if (ferror(fh)) { @@ -473,6 +491,7 @@ struct GuestFileRead *qmp_guest_file_read(int64_t handle, bool has_count, if (read_count) { read_data->buf_b64 = g_base64_encode(buf, read_count); } + gfh->state = RW_STATE_READING; } g_free(buf); clearerr(fh); @@ -496,6 +515,16 @@ GuestFileWrite *qmp_guest_file_write(int64_t handle, const char *buf_b64, } fh = gfh->fh; + + if (gfh->state == RW_STATE_READING) { + int ret = fseek(fh, 0, SEEK_CUR); + if (ret == -1) { + error_setg_errno(errp, errno, "failed to seek file"); + return NULL; + } + gfh->state = RW_STATE_NEW; + } + buf = g_base64_decode(buf_b64, &buf_len); if (!has_count) { @@ -515,6 +544,7 @@ GuestFileWrite *qmp_guest_file_write(int64_t handle, const char *buf_b64, write_data = g_new0(GuestFileWrite, 1); write_data->count = write_count; write_data->eof = feof(fh); + gfh->state = RW_STATE_WRITING; } g_free(buf); clearerr(fh); @@ -538,10 +568,15 @@ struct GuestFileSeek *qmp_guest_file_seek(int64_t handle, int64_t offset, ret = fseek(fh, offset, whence); if (ret == -1) { error_setg_errno(errp, errno, "failed to seek file"); + if (errno == ESPIPE) { + /* file is non-seekable, stdio shouldn't be buffering anyways */ + gfh->state = RW_STATE_NEW; + } } else { seek_data = g_new0(GuestFileSeek, 1); seek_data->position = ftell(fh); seek_data->eof = feof(fh); + gfh->state = RW_STATE_NEW; } clearerr(fh); @@ -562,6 +597,8 @@ void qmp_guest_file_flush(int64_t handle, Error **errp) ret = fflush(fh); if (ret == EOF) { error_setg_errno(errp, errno, "failed to flush file"); + } else { + gfh->state = RW_STATE_NEW; } } |