Message ID | 1364903250-10429-14-git-send-email-xiawenc@linux.vnet.ibm.com |
---|---|
State | New |
Headers | show |
On Tue, Apr 02, 2013 at 07:47:26PM +0800, Wenchao Xia wrote: > 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; Leaks buf. > 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; > > bs = bdrv_snapshots(); > if (!bs) { > @@ -2509,11 +2509,16 @@ void do_info_snapshots(Monitor *mon, const QDict *qdict) > } > > if (total > 0) { Please declare buf here since it is only used in this scope.
Stefan Hajnoczi <stefanha@gmail.com> writes: > On Tue, Apr 02, 2013 at 07:47:26PM +0800, Wenchao Xia wrote: >> 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; > > Leaks buf. Trivially avoided my moving the initialization behind the return. >> 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; >> >> bs = bdrv_snapshots(); >> if (!bs) { >> @@ -2509,11 +2509,16 @@ void do_info_snapshots(Monitor *mon, const >> QDict *qdict) >> } >> >> if (total > 0) { > > Please declare buf here since it is only used in this scope. Matter of taste. I'd keep it where it is :)
Wenchao Xia <xiawenc@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 <xiawenc@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"); > }
>> >> -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. > HMP code later need to call this function, and then print buf to monitor console, which is the goal of this patch. >> info->actual_size); >> } >> >> 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. > will remove.
Wenchao Xia <xiawenc@linux.vnet.ibm.com> writes: >>> >>> -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. >> > HMP code later need to call this function, and then print buf to > monitor console, which is the goal of this patch. Aha, the actual problem is "print either to stdout or to current monitor", so that we can share code among qemu-img and monitor commands. Such sharing is good, and the problem is real. bdrv_snapshot_dump() solves it this way: print to a fixed-size buffer, which the caller either prints to stdout (qemu-img) or to the current monitor (info snapshots). Your patch makes the buffer flexible. Improvement. But in my opinion, the detour through the buffer is silly. Why not simply use a print function that does the right thing? We already have such a function for "print either to stderr or to current monitor": error_printf(). Could easily add one for stdout. [...]
于 2013-4-11 20:05, Markus Armbruster 写道: > Wenchao Xia <xiawenc@linux.vnet.ibm.com> writes: > >>>> >>>> -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. >>> >> HMP code later need to call this function, and then print buf to >> monitor console, which is the goal of this patch. > > Aha, the actual problem is "print either to stdout or to current > monitor", so that we can share code among qemu-img and monitor commands. > Such sharing is good, and the problem is real. > > bdrv_snapshot_dump() solves it this way: print to a fixed-size buffer, > which the caller either prints to stdout (qemu-img) or to the current > monitor (info snapshots). > > Your patch makes the buffer flexible. Improvement. > > But in my opinion, the detour through the buffer is silly. Why not > simply use a print function that does the right thing? > > We already have such a function for "print either to stderr or to > current monitor": error_printf(). Could easily add one for stdout. > > [...] > Indeed it is a better way, how about: void message_printf(const char *fmt, ...); I am not sure where should this function be placed, hmp.c?
Wenchao Xia <xiawenc@linux.vnet.ibm.com> writes: > 于 2013-4-11 20:05, Markus Armbruster 写道: >> Wenchao Xia <xiawenc@linux.vnet.ibm.com> writes: >> >>>>> >>>>> -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. >>>> >>> HMP code later need to call this function, and then print buf to >>> monitor console, which is the goal of this patch. >> >> Aha, the actual problem is "print either to stdout or to current >> monitor", so that we can share code among qemu-img and monitor commands. >> Such sharing is good, and the problem is real. >> >> bdrv_snapshot_dump() solves it this way: print to a fixed-size buffer, >> which the caller either prints to stdout (qemu-img) or to the current >> monitor (info snapshots). >> >> Your patch makes the buffer flexible. Improvement. >> >> But in my opinion, the detour through the buffer is silly. Why not >> simply use a print function that does the right thing? >> >> We already have such a function for "print either to stderr or to >> current monitor": error_printf(). Could easily add one for stdout. >> >> [...] >> > Indeed it is a better way, how about: > void message_printf(const char *fmt, ...); > I am not sure where should this function be placed, > hmp.c? I figure it needs to go in a file that's linked into the utilities, too. I think these are in make variables util-obj-y, stub-obj-y. I'd be tempted to put it into qemu-error.c. If you don't like that because it's not about errors, consider renaming the file :)
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; @@ -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) 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; 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"); }
This patch would allow hmp use them just like qemu-img, and avoid string truncation. Signed-off-by: Wenchao Xia <xiawenc@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(-)