| Message ID | 1386148259-10962-5-git-send-email-xiawenc@linux.vnet.ibm.com |
|---|---|
| State | New |
| Headers | show |
On 12/04/2013 02:10 AM, Wenchao Xia wrote: > Now qemu-img convert have similar options as qemu-nbd for internal > snapshot. > > Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com> > --- > @@ -1183,6 +1189,18 @@ static int img_convert(int argc, char **argv) > case 's': > snapshot_name = optarg; > break; > + case 'l': > + if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { > + sn_opts = qemu_opts_parse(&internal_snapshot_opts, optarg, 0); > + if (!sn_opts) { > + error_report("Failed in parsing snapshot param '%s'", > + optarg); > + return 1; > + } > + } else { > + snapshot_name = optarg; > + } > + break; Do we want a followup patch that makes it an error to use -l and -s together? Without such a patch, we have the odd behavior that: convert -l name1 -s name2 loads name2, but: convert -l snapshot.name=name1 -s name2 loads name1. Confusing that the choice of HOW the argument to -l is specified determines whether the -s has any impact. For that matter, why can't '-s' and '-l' be made synonyms of each other? In other words, why not support: convert -s snapshot.name=name1
于 2013/12/5 4:42, Eric Blake 写道: > On 12/04/2013 02:10 AM, Wenchao Xia wrote: >> Now qemu-img convert have similar options as qemu-nbd for internal >> snapshot. >> >> Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com> >> --- > >> @@ -1183,6 +1189,18 @@ static int img_convert(int argc, char **argv) >> case 's': >> snapshot_name = optarg; >> break; >> + case 'l': >> + if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { >> + sn_opts = qemu_opts_parse(&internal_snapshot_opts, optarg, 0); >> + if (!sn_opts) { >> + error_report("Failed in parsing snapshot param '%s'", >> + optarg); >> + return 1; >> + } >> + } else { >> + snapshot_name = optarg; >> + } >> + break; > > Do we want a followup patch that makes it an error to use -l and -s > together? Without such a patch, we have the odd behavior that: > > convert -l name1 -s name2 > > loads name2, but: > > convert -l snapshot.name=name1 -s name2 > > loads name1. Confusing that the choice of HOW the argument to -l is > specified determines whether the -s has any impact. > > For that matter, why can't '-s' and '-l' be made synonyms of each other? > In other words, why not support: > > convert -s snapshot.name=name1 > Previous I planned to use -l for internal snapshot in all possible program, since -s is taken as external snapshot in qemu, qemu-nbd. let -s stands for internal in qemu-img convert only, may bring confuse to user, so I deprecated it instead of enhance it(I want to remove it but may bring compatiablity issue). Yes, it should report error when both specified, will send a patch if you agree '-l' should still be used.
>> >> convert -s snapshot.name=name1 >> > Previous I planned to use -l for internal snapshot in all possible > program, since -s is taken as external snapshot in qemu, qemu-nbd. > let -s stands for internal in qemu-img convert only, may bring > confuse to user, so I deprecated it instead of enhance it(I want > to remove it but may bring compatiablity issue). > Yes, it should report error when both specified, will send a patch > if you agree '-l' should still be used. > > Eric, I hope to get your idea before patching, any comments?
On 12/08/2013 08:43 PM, Wenchao Xia wrote: >>> >>> convert -s snapshot.name=name1 >>> >> Previous I planned to use -l for internal snapshot in all possible >> program, since -s is taken as external snapshot in qemu, qemu-nbd. Consistency in command line options between different tools is nice, but is less important than adding functionality. I'm perfectly fine if we use -l in one tool and -s in another, as long as the documentation is clear on how to spell the option for the tool I want to use. >> let -s stands for internal in qemu-img convert only, may bring >> confuse to user, so I deprecated it instead of enhance it(I want >> to remove it but may bring compatiablity issue). >> Yes, it should report error when both specified, will send a patch >> if you agree '-l' should still be used. >> >> > Eric, I hope to get your idea before patching, any comments? > My biggest concern was that by adding -l as a superset of -s, but not taking care of the relation between the two, you created odd command line usage patterns. For qemu-img, it may be simpler to just make -s do everything, instead of trying to deprecate it (that is, adding -l for consistency with other tools while breaking -s isn't nice).
于 2013/12/13 21:44, Eric Blake 写道: > On 12/08/2013 08:43 PM, Wenchao Xia wrote: >>>> >>>> convert -s snapshot.name=name1 >>>> >>> Previous I planned to use -l for internal snapshot in all possible >>> program, since -s is taken as external snapshot in qemu, qemu-nbd. > > Consistency in command line options between different tools is nice, but > is less important than adding functionality. I'm perfectly fine if we > use -l in one tool and -s in another, as long as the documentation is > clear on how to spell the option for the tool I want to use. > >>> let -s stands for internal in qemu-img convert only, may bring >>> confuse to user, so I deprecated it instead of enhance it(I want >>> to remove it but may bring compatiablity issue). >>> Yes, it should report error when both specified, will send a patch >>> if you agree '-l' should still be used. >>> >>> >> Eric, I hope to get your idea before patching, any comments? >> > > My biggest concern was that by adding -l as a superset of -s, but not > taking care of the relation between the two, you created odd command > line usage patterns. For qemu-img, it may be simpler to just make -s do > everything, instead of trying to deprecate it (that is, adding -l for > consistency with other tools while breaking -s isn't nice). > OK, there is still one cornor case to consider: -s snapshot.name=name1 It may change the semantics if a caller used qemu-img convert as above before, although it seems insane.:)
diff --git a/qemu-img-cmds.hx b/qemu-img-cmds.hx index da1d965..d029609 100644 --- a/qemu-img-cmds.hx +++ b/qemu-img-cmds.hx @@ -34,9 +34,9 @@ STEXI ETEXI DEF("convert", img_convert, - "convert [-c] [-p] [-q] [-n] [-f fmt] [-t cache] [-O output_fmt] [-o options] [-s snapshot_name] [-S sparse_size] filename [filename2 [...]] output_filename") + "convert [-c] [-p] [-q] [-n] [-f fmt] [-t cache] [-O output_fmt] [-o options] [-s snapshot_id_or_name] [-l snapshot_param] [-S sparse_size] filename [filename2 [...]] output_filename") STEXI -@item convert [-c] [-p] [-q] [-n] [-f @var{fmt}] [-t @var{cache}] [-O @var{output_fmt}] [-o @var{options}] [-s @var{snapshot_name}] [-S @var{sparse_size}] @var{filename} [@var{filename2} [...]] @var{output_filename} +@item convert [-c] [-p] [-q] [-n] [-f @var{fmt}] [-t @var{cache}] [-O @var{output_fmt}] [-o @var{options}] [-s @var{snapshot_id_or_name}] [-l @var{snapshot_param}] [-S @var{sparse_size}] @var{filename} [@var{filename2} [...]] @var{output_filename} ETEXI DEF("info", img_info, diff --git a/qemu-img.c b/qemu-img.c index a73beb5..ee940c2 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -93,6 +93,11 @@ static void help(void) " 'options' is a comma separated list of format specific options in a\n" " name=value format. Use -o ? for an overview of the options supported by the\n" " used format\n" + " 'snapshot_param' is param used for internal snapshot, format\n" + " is 'snapshot.id=[ID],snapshot.name=[NAME]', or\n" + " '[ID_OR_NAME]'\n" + " 'snapshot_id_or_name' is deprecated, use 'snapshot_param'\n" + " instead\n" " '-c' indicates that target image must be compressed (qcow format only)\n" " '-u' enables unsafe rebasing. It is assumed that old and new backing file\n" " match exactly. The image doesn't need a working backing file before\n" @@ -1140,6 +1145,7 @@ static int img_convert(int argc, char **argv) int min_sparse = 8; /* Need at least 4k of zeros for sparse detection */ bool quiet = false; Error *local_err = NULL; + QemuOpts *sn_opts = NULL; fmt = NULL; out_fmt = "raw"; @@ -1148,7 +1154,7 @@ static int img_convert(int argc, char **argv) compress = 0; skip_create = 0; for(;;) { - c = getopt(argc, argv, "f:O:B:s:hce6o:pS:t:qn"); + c = getopt(argc, argv, "f:O:B:s:hce6o:pS:t:qnl:"); if (c == -1) { break; } @@ -1183,6 +1189,18 @@ static int img_convert(int argc, char **argv) case 's': snapshot_name = optarg; break; + case 'l': + if (strstart(optarg, SNAPSHOT_OPT_BASE, NULL)) { + sn_opts = qemu_opts_parse(&internal_snapshot_opts, optarg, 0); + if (!sn_opts) { + error_report("Failed in parsing snapshot param '%s'", + optarg); + return 1; + } + } else { + snapshot_name = optarg; + } + break; case 'S': { int64_t sval; @@ -1254,7 +1272,12 @@ static int img_convert(int argc, char **argv) total_sectors += bs_sectors; } - if (snapshot_name != NULL) { + if (sn_opts) { + ret = bdrv_snapshot_load_tmp(bs[0], + qemu_opt_get(sn_opts, SNAPSHOT_OPT_ID), + qemu_opt_get(sn_opts, SNAPSHOT_OPT_NAME), + &local_err); + } else if (snapshot_name != NULL) { if (bs_n > 1) { error_report("No support for concatenating multiple snapshot"); ret = -1; @@ -1262,13 +1285,13 @@ static int img_convert(int argc, char **argv) } bdrv_snapshot_load_tmp_by_id_or_name(bs[0], snapshot_name, &local_err); - if (error_is_set(&local_err)) { - error_report("Failed to load snapshot: %s", - error_get_pretty(local_err)); - error_free(local_err); - ret = -1; - goto out; - } + } + if (error_is_set(&local_err)) { + error_report("Failed to load snapshot: %s", + error_get_pretty(local_err)); + error_free(local_err); + ret = -1; + goto out; } /* Find driver and parse its options */ @@ -1559,6 +1582,9 @@ out: free_option_parameters(create_options); free_option_parameters(param); qemu_vfree(buf); + if (sn_opts) { + qemu_opts_del(sn_opts); + } if (out_bs) { bdrv_unref(out_bs); } diff --git a/qemu-img.texi b/qemu-img.texi index 768054e..fbdbfa7 100644 --- a/qemu-img.texi +++ b/qemu-img.texi @@ -46,7 +46,11 @@ is the destination disk image filename is a comma separated list of format specific options in a name=value format. Use @code{-o ?} for an overview of the options supported by the used format or see the format descriptions below for details. - +@item snapshot_param +is param used for internal snapshot, format is +'snapshot.id=[ID],snapshot.name=[NAME]' or '[ID_OR_NAME]' +@item snapshot_id_or_name +is deprecated, use snapshot_param instead @item -c indicates that target image must be compressed (qcow format only) @@ -179,10 +183,10 @@ Error on reading data @end table -@item convert [-c] [-p] [-n] [-f @var{fmt}] [-t @var{cache}] [-O @var{output_fmt}] [-o @var{options}] [-s @var{snapshot_name}] [-S @var{sparse_size}] @var{filename} [@var{filename2} [...]] @var{output_filename} +@item convert [-c] [-p] [-n] [-f @var{fmt}] [-t @var{cache}] [-O @var{output_fmt}] [-o @var{options}] [-s @var{snapshot_id_or_name}] [-l @var{snapshot_param}] [-S @var{sparse_size}] @var{filename} [@var{filename2} [...]] @var{output_filename} -Convert the disk image @var{filename} or a snapshot @var{snapshot_name} to disk image @var{output_filename} -using format @var{output_fmt}. It can be optionally compressed (@code{-c} +Convert the disk image @var{filename} or a snapshot @var{snapshot_param}(@var{snapshot_id_or_name} is deprecated) +to disk image @var{output_filename} using format @var{output_fmt}. It can be optionally compressed (@code{-c} option) or use any format specific options like encryption (@code{-o} option). Only the formats @code{qcow} and @code{qcow2} support compression. The
Now qemu-img convert have similar options as qemu-nbd for internal snapshot. Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com> --- qemu-img-cmds.hx | 4 ++-- qemu-img.c | 44 +++++++++++++++++++++++++++++++++++--------- qemu-img.texi | 12 ++++++++---- 3 files changed, 45 insertions(+), 15 deletions(-)