[Qemu-devel] [RFC PATCH 07/20] Introduce qemu_put_vector() and qemu_put_vector_prepare() to use put_vector() in QEMUFile.

[Yoshiaki Tamura]

For fool proof purpose, qemu_put_vector_parepare should be called
before qemu_put_vector.  Then, if qemu_put_* functions except this is
called after qemu_put_vector_prepare, program will abort().

Signed-off-by: Yoshiaki Tamura <address@hidden>
---
 hw/hw.h  |    2 ++
 savevm.c |   53 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 55 insertions(+), 0 deletions(-)

diff --git a/hw/hw.h b/hw/hw.h
index 921cf90..10e6dda 100644
--- a/hw/hw.h
+++ b/hw/hw.h
@@ -77,6 +77,8 @@ void qemu_fflush(QEMUFile *f);
 int qemu_fclose(QEMUFile *f);
 void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size);
 void qemu_put_byte(QEMUFile *f, int v);
+void qemu_put_vector(QEMUFile *f, QEMUIOVector *qiov);
+void qemu_put_vector_prepare(QEMUFile *f);
 void *qemu_realloc_buffer(QEMUFile *f, int size);
 void qemu_clear_buffer(QEMUFile *f);
 
diff --git a/savevm.c b/savevm.c
index 944e788..22d928c 100644
--- a/savevm.c
+++ b/savevm.c
@@ -180,6 +180,7 @@ struct QEMUFile {
     uint8_t *buf;
 
     int has_error;
+    int prepares_vector;
 };
 
 typedef struct QEMUFileStdio
@@ -557,6 +558,58 @@ void qemu_put_byte(QEMUFile *f, int v)
         qemu_fflush(f);
 }
 
+void qemu_put_vector(QEMUFile *f, QEMUIOVector *v)
+{
+    struct iovec *iov;
+    int cnt;
+    size_t bufsize;
+    uint8_t *buf;
+
+    if (qemu_file_get_rate_limit(f) != 0) {
+        fprintf(stderr,
+                "Attempted to write vector while bandwidth limit is not 
zero.\n");
+        abort();
+    }
+
+    /* checks prepares vector.
+     * For fool proof purpose, qemu_put_vector_parepare should be called
+     * before qemu_put_vector.  Then, if qemu_put_* functions except this
+     * is called after qemu_put_vector_prepare, program will abort().
+     */
+    if (!f->prepares_vector) {
+        fprintf(stderr,
+            "You should prepare with qemu_put_vector_prepare.\n");
+        abort();
+    } else if (f->prepares_vector && f->buf_index != 0) {
+        fprintf(stderr, "Wrote data after qemu_put_vector_prepare.\n");
+        abort();
+    }
+    f->prepares_vector = 0;
+
+    if (f->put_vector) {
+        qemu_iovec_to_vector(v, &iov, &cnt);
+        f->put_vector(f->opaque, iov, 0, cnt);
+    } else {
+        qemu_iovec_to_size(v, &bufsize);
+        buf = qemu_malloc(bufsize + 1 /* for '\0' */);
+        qemu_iovec_to_buffer(v, buf);
+        qemu_put_buffer(f, buf, bufsize);
+        qemu_free(buf);
+    }
+
+}
+
+void qemu_put_vector_prepare(QEMUFile *f)
+{
+    if (f->prepares_vector) {
+        /* prepare vector */
+        fprintf(stderr, "Attempted to prepare vector twice\n");
+        abort();
+    }
+    f->prepares_vector = 1;
+    qemu_fflush(f);
+}
+
 int qemu_get_buffer(QEMUFile *f, uint8_t *buf, int size1)
 {
     int size, l;
-- 
1.7.0.31.g1df487