[Qemu-devel] [PATCH 01/18] Make QEMUFile buf expandable, and introduce qemu_realloc_buffer() and qemu_clear_buffer().

[Yoshiaki Tamura]

Currently buf size is fixed at 32KB.  It would be useful if it could
be flexible.

Signed-off-by: Yoshiaki Tamura <address@hidden>
---
 hw/hw.h  |    2 ++
 savevm.c |   20 +++++++++++++++++++-
 2 files changed, 21 insertions(+), 1 deletions(-)

diff --git a/hw/hw.h b/hw/hw.h
index 1b09039..f90ff15 100644
--- a/hw/hw.h
+++ b/hw/hw.h
@@ -58,6 +58,8 @@ 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_realloc_buffer(QEMUFile *f, int size);
+void qemu_clear_buffer(QEMUFile *f);
 
 static inline void qemu_put_ubyte(QEMUFile *f, unsigned int v)
 {
diff --git a/savevm.c b/savevm.c
index 03fce62..d293f9c 100644
--- a/savevm.c
+++ b/savevm.c
@@ -171,7 +171,8 @@ struct QEMUFile {
                            when reading */
     int buf_index;
     int buf_size; /* 0 when writing */
-    uint8_t buf[IO_BUF_SIZE];
+    int buf_max_size;
+    uint8_t *buf;
 
     int has_error;
 };
@@ -422,6 +423,9 @@ QEMUFile *qemu_fopen_ops(void *opaque, 
QEMUFilePutBufferFunc *put_buffer,
     f->get_rate_limit = get_rate_limit;
     f->is_write = 0;
 
+    f->buf_max_size = IO_BUF_SIZE;
+    f->buf = qemu_malloc(sizeof(uint8_t) * f->buf_max_size);
+
     return f;
 }
 
@@ -452,6 +456,19 @@ void qemu_fflush(QEMUFile *f)
     }
 }
 
+void *qemu_realloc_buffer(QEMUFile *f, int size)
+{
+    f->buf_max_size = size;
+    f->buf = qemu_realloc(f->buf, f->buf_max_size);
+
+    return f->buf;
+}
+
+void qemu_clear_buffer(QEMUFile *f)
+{
+    f->buf_size = f->buf_index = f->buf_offset = 0;
+}
+
 static void qemu_fill_buffer(QEMUFile *f)
 {
     int len;
@@ -477,6 +494,7 @@ int qemu_fclose(QEMUFile *f)
     qemu_fflush(f);
     if (f->close)
         ret = f->close(f->opaque);
+    qemu_free(f->buf);
     qemu_free(f);
     return ret;
 }
-- 
1.7.1.2