Wenchao Xia <xiaw...@linux.vnet.ibm.com> writes:
> This patch would allow hmp use them just like qemu-img, and avoid
> string truncation.
>
> Signed-off-by: Wenchao Xia <xiaw...@linux.vnet.ibm.com>
> ---
> block/qapi.c | 65
> +++++++++++++++++++++++++++-----------------------
> include/block/qapi.h | 4 +-
> qemu-img.c | 22 ++++++++++++----
> savevm.c | 11 ++++++--
> 4 files changed, 61 insertions(+), 41 deletions(-)
>
> diff --git a/block/qapi.c b/block/qapi.c
> index df63c97..e27519e 100644
> --- a/block/qapi.c
> +++ b/block/qapi.c
> @@ -327,7 +327,7 @@ BlockInfoList *qmp_query_block(Error **errp)
> return NULL;
> }
>
> -char *bdrv_snapshot_dump(char *buf, int buf_size, QEMUSnapshotInfo *sn)
> +void bdrv_snapshot_dump(GString *buf, QEMUSnapshotInfo *sn)
> {
> char buf1[128], date_buf[128], clock_buf[128];
> struct tm tm;
I like this change, because it replaces an arbitrarily sized buffer by a
flexible one.
> @@ -335,9 +335,8 @@ char *bdrv_snapshot_dump(char *buf, int buf_size,
> QEMUSnapshotInfo *sn)
> int64_t secs;
>
> if (!sn) {
> - snprintf(buf, buf_size,
> - "%-10s%-20s%7s%20s%15s",
> - "ID", "TAG", "VM SIZE", "DATE", "VM CLOCK");
> + g_string_append_printf(buf, "%-10s%-20s%7s%20s%15s",
> + "ID", "TAG", "VM SIZE", "DATE", "VM CLOCK");
> } else {
> ti = sn->date_sec;
> localtime_r(&ti, &tm);
> @@ -350,17 +349,17 @@ char *bdrv_snapshot_dump(char *buf, int buf_size,
> QEMUSnapshotInfo *sn)
> (int)((secs / 60) % 60),
> (int)(secs % 60),
> (int)((sn->vm_clock_nsec / 1000000) % 1000));
> - snprintf(buf, buf_size,
> - "%-10s%-20s%7s%20s%15s",
> - sn->id_str, sn->name,
> - get_human_readable_size(buf1, sizeof(buf1),
> sn->vm_state_size),
> - date_buf,
> - clock_buf);
> + g_string_append_printf(buf,
> + "%-10s%-20s%7s%20s%15s",
> + sn->id_str, sn->name,
> + get_human_readable_size(buf1, sizeof(buf1),
> + sn->vm_state_size),
> + date_buf,
> + clock_buf);
> }
> - return buf;
> }
>
> -void bdrv_image_info_dump(ImageInfo *info)
> +void bdrv_image_info_dump(GString *buf, ImageInfo *info)
> {
> char size_buf[128], dsize_buf[128];
> if (!info->has_actual_size) {
> @@ -370,43 +369,48 @@ void bdrv_image_info_dump(ImageInfo *info)
I don't like this change, because it introduces buffering for no
discernible reason. Unless you can show me one, I'd like you to keep
printing directly.
> info->actual_size);
> }
> get_human_readable_size(size_buf, sizeof(size_buf), info->virtual_size);
> - printf("image: %s\n"
> - "file format: %s\n"
> - "virtual size: %s (%" PRId64 " bytes)\n"
> - "disk size: %s\n",
> - info->filename, info->format, size_buf,
> - info->virtual_size,
> - dsize_buf);
> + g_string_append_printf(buf,
> + "image: %s\n"
> + "file format: %s\n"
> + "virtual size: %s (%" PRId64 " bytes)\n"
> + "disk size: %s\n",
> + info->filename, info->format, size_buf,
> + info->virtual_size,
> + dsize_buf);
>
> if (info->has_encrypted && info->encrypted) {
> - printf("encrypted: yes\n");
> + g_string_append_printf(buf, "encrypted: yes\n");
> }
>
> if (info->has_cluster_size) {
> - printf("cluster_size: %" PRId64 "\n", info->cluster_size);
> + g_string_append_printf(buf, "cluster_size: %" PRId64 "\n",
> + info->cluster_size);
> }
>
> if (info->has_dirty_flag && info->dirty_flag) {
> - printf("cleanly shut down: no\n");
> + g_string_append_printf(buf, "cleanly shut down: no\n");
> }
>
> if (info->has_backing_filename) {
> - printf("backing file: %s", info->backing_filename);
> + g_string_append_printf(buf, "backing file: %s",
> + info->backing_filename);
> if (info->has_full_backing_filename) {
> - printf(" (actual path: %s)", info->full_backing_filename);
> + g_string_append_printf(buf, " (actual path: %s)",
> + info->full_backing_filename);
> }
> - putchar('\n');
> + g_string_append_printf(buf, "\n");
> if (info->has_backing_filename_format) {
> - printf("backing file format: %s\n",
> info->backing_filename_format);
> + g_string_append_printf(buf, "backing file format: %s\n",
> + info->backing_filename_format);
> }
> }
>
> if (info->has_snapshots) {
> SnapshotInfoList *elem;
> - char buf[256];
>
> - printf("Snapshot list:\n");
> - printf("%s\n", bdrv_snapshot_dump(buf, sizeof(buf), NULL));
> + g_string_append_printf(buf, "Snapshot list:\n");
> + bdrv_snapshot_dump(buf, NULL);
> + g_string_append_printf(buf, "\n");
>
> /* Ideally bdrv_snapshot_dump() would operate on SnapshotInfoList but
> * we convert to the block layer's native QEMUSnapshotInfo for now.
> @@ -422,7 +426,8 @@ void bdrv_image_info_dump(ImageInfo *info)
>
> pstrcpy(sn.id_str, sizeof(sn.id_str), elem->value->id);
> pstrcpy(sn.name, sizeof(sn.name), elem->value->name);
> - printf("%s\n", bdrv_snapshot_dump(buf, sizeof(buf), &sn));
> + bdrv_snapshot_dump(buf, &sn);
> + g_string_append_printf(buf, "\n");
> }
> }
> }
> diff --git a/include/block/qapi.h b/include/block/qapi.h
> index 237660f..dc1e090 100644
> --- a/include/block/qapi.h
> +++ b/include/block/qapi.h
> @@ -38,6 +38,6 @@ int bdrv_query_image_info(BlockDriverState *bs,
> void bdrv_query_info(BlockDriverState *bs,
> BlockInfo **p_info,
> Error **errp);
> -char *bdrv_snapshot_dump(char *buf, int buf_size, QEMUSnapshotInfo *sn);
> -void bdrv_image_info_dump(ImageInfo *info);
> +void bdrv_snapshot_dump(GString *buf, QEMUSnapshotInfo *sn);
> +void bdrv_image_info_dump(GString *buf, ImageInfo *info);
> #endif
> diff --git a/qemu-img.c b/qemu-img.c
> index 5b229a9..032f68c 100644
> --- a/qemu-img.c
> +++ b/qemu-img.c
> @@ -1558,18 +1558,24 @@ static void dump_snapshots(BlockDriverState *bs)
> {
> QEMUSnapshotInfo *sn_tab, *sn;
> int nb_sns, i;
> - char buf[256];
> + GString *buf = g_string_new(NULL);
>
> nb_sns = bdrv_snapshot_list(bs, &sn_tab);
> if (nb_sns <= 0)
> return;
> - printf("Snapshot list:\n");
> - printf("%s\n", bdrv_snapshot_dump(buf, sizeof(buf), NULL));
> + g_string_append_printf(buf, "Snapshot list:\n");
> + bdrv_snapshot_dump(buf, NULL);
> + g_string_append_printf(buf, "\n");
> for(i = 0; i < nb_sns; i++) {
> sn = &sn_tab[i];
> - printf("%s\n", bdrv_snapshot_dump(buf, sizeof(buf), sn));
> + bdrv_snapshot_dump(buf, sn);
> + g_string_append_printf(buf, "\n");
> }
> +
> + printf("%s", buf->str);
> + g_string_free(buf, true);
> g_free(sn_tab);
> +
> }
>
> static void dump_json_image_info_list(ImageInfoList *list)
> @@ -1610,15 +1616,19 @@ static void dump_human_image_info_list(ImageInfoList
> *list)
> {
> ImageInfoList *elem;
> bool delim = false;
> + GString *buf = g_string_new(NULL);
>
> for (elem = list; elem; elem = elem->next) {
> if (delim) {
> - printf("\n");
> + g_string_append_printf(buf, "\n");
> }
> delim = true;
>
> - bdrv_image_info_dump(elem->value);
> + bdrv_image_info_dump(buf, elem->value);
> }
> +
> + printf("%s", buf->str);
> + g_string_free(buf, true);
> }
>
> static gboolean str_equal_func(gconstpointer a, gconstpointer b)
> diff --git a/savevm.c b/savevm.c
> index e4e0008..ce0bbe1 100644
> --- a/savevm.c
> +++ b/savevm.c
> @@ -2466,7 +2466,7 @@ void do_info_snapshots(Monitor *mon, const QDict *qdict)
> int nb_sns, i, ret, available;
> int total;
> int *available_snapshots;
> - char buf[256];
> + GString *buf = NULL;
Useless initialization. But if you keep bdrv_snapshot_dump() printing,
it all goes away.
>
> bs = bdrv_snapshots();
> if (!bs) {
> @@ -2509,11 +2509,16 @@ void do_info_snapshots(Monitor *mon, const QDict
> *qdict)
> }
>
> if (total > 0) {
> - monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf),
> NULL));
> + buf = g_string_new(NULL);
> + bdrv_snapshot_dump(buf, NULL);
> + g_string_append_printf(buf, "\n");
> for (i = 0; i < total; i++) {
> sn = &sn_tab[available_snapshots[i]];
> - monitor_printf(mon, "%s\n", bdrv_snapshot_dump(buf, sizeof(buf),
> sn));
> + bdrv_snapshot_dump(buf, sn);
> + g_string_append_printf(buf, "\n");
> }
> + monitor_printf(mon, "%s", buf->str);
> + g_string_free(buf, true);
> } else {
> monitor_printf(mon, "There is no suitable snapshot available\n");
> }
