From 6625262c7099feaf741ff435dd91a574331635a7 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=D0=BD=D0=B0=D0=B1?= Date: Thu, 24 Mar 2022 21:07:07 +0100 Subject: [PATCH] man: zfs-send.8: fix -X synopses and description MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Also clean up the horrendously verbose -X handling in zfs_main() Reviewed-by: Brian Behlendorf Signed-off-by: Ahelenia Ziemiańska Closes #13352 --- cmd/zfs/zfs_main.c | 102 ++++++++++++++------------------------------ man/man8/zfs-send.8 | 31 ++++++-------- 2 files changed, 45 insertions(+), 88 deletions(-) diff --git a/cmd/zfs/zfs_main.c b/cmd/zfs/zfs_main.c index 2a771c6d6..863f93c8a 100644 --- a/cmd/zfs/zfs_main.c +++ b/cmd/zfs/zfs_main.c @@ -315,9 +315,9 @@ get_usage(zfs_help_t idx) case HELP_ROLLBACK: return (gettext("\trollback [-rRf] \n")); case HELP_SEND: - return (gettext("\tsend [-DnPpRvLecwhb] " - "[-X dataset[,dataset]...] " - "[-[i|I] snapshot] \n" + return (gettext("\tsend [-DLPbcehnpsvw] " + "[-i|-I snapshot]\n" + "\t [-R [-X dataset[,dataset]...]] \n" "\tsend [-DnvPLecw] [-i snapshot|bookmark] " "\n" "\tsend [-DnPpvLec] [-i bookmark|snapshot] " @@ -4315,73 +4315,27 @@ usage: return (-1); } +/* + * Array of prefixes to exclude – + * a linear search, even if executed for each dataset, + * is plenty good enough. + */ typedef struct zfs_send_exclude_arg { size_t count; - char **list; + const char **list; } zfs_send_exclude_arg_t; -/* - * This function creates the zfs_send_exclude_arg_t - * object described above; it can be called multiple - * times, and the input can be comma-separated. - * This is NOT the most efficient data layout; however, - * I couldn't think of a non-pathological case where - * it should have more than a couple dozen instances - * of excludes. If that turns out to be used in - * practice, we might want to instead use a tree. - */ -static void -add_dataset_excludes(char *exclude, zfs_send_exclude_arg_t *context) -{ - char *tok; - while ((tok = strsep(&exclude, ",")) != NULL) { - if (!zfs_name_valid(tok, ZFS_TYPE_DATASET) || - strchr(tok, '/') == NULL) { - (void) fprintf(stderr, gettext("-X %s: " - "not a valid non-root dataset name.\n"), tok); - usage(B_FALSE); - } - context->list = safe_realloc(context->list, - (sizeof (char *)) * (context->count + 1)); - context->list[context->count++] = tok; - } -} - -static void -free_dataset_excludes(zfs_send_exclude_arg_t *exclude_list) -{ - free(exclude_list->list); -} - -/* - * This is the call back used by zfs_send to - * determine if a dataset should be skipped. - * As stated above, this is not the most efficient - * data structure to use, but as long as the - * number of excluded datasets is relatively - * small (a couple of dozen or so), it won't - * have a big impact on performance on modern - * processors. Since it's excluding hierarchies, - * we'd probably want to move to a more complex - * tree structure in that case. - */ static boolean_t zfs_do_send_exclude(zfs_handle_t *zhp, void *context) { - zfs_send_exclude_arg_t *exclude = context; + zfs_send_exclude_arg_t *excludes = context; const char *name = zfs_get_name(zhp); - for (size_t indx = 0; indx < exclude->count; indx++) { - char *exclude_name = exclude->list[indx]; - size_t len = strlen(exclude_name); - /* If it's shorter, it can't possibly match */ - if (strlen(name) < len) - continue; - if (strncmp(name, exclude_name, len) == 0 && - (name[len] == '/' || name[len] == '\0' || - name[len] == '@')) { + for (size_t i = 0; i < excludes->count; ++i) { + size_t len = strlen(excludes->list[i]); + if (strncmp(name, excludes->list[i], len) == 0 && + memchr("/@", name[len], sizeof ("/@"))) return (B_FALSE); - } } return (B_TRUE); @@ -4402,11 +4356,11 @@ zfs_do_send(int argc, char **argv) int c, err; nvlist_t *dbgnv = NULL; char *redactbook = NULL; - zfs_send_exclude_arg_t exclude_context = { 0 }; + zfs_send_exclude_arg_t excludes = { 0 }; struct option long_options[] = { {"replicate", no_argument, NULL, 'R'}, - {"skip-missing", no_argument, NULL, 's'}, + {"skip-missing", no_argument, NULL, 's'}, {"redact", required_argument, NULL, 'd'}, {"props", no_argument, NULL, 'p'}, {"parsable", no_argument, NULL, 'P'}, @@ -4430,7 +4384,18 @@ zfs_do_send(int argc, char **argv) long_options, NULL)) != -1) { switch (c) { case 'X': - add_dataset_excludes(optarg, &exclude_context); + for (char *ds; (ds = strsep(&optarg, ",")) != NULL; ) { + if (!zfs_name_valid(ds, ZFS_TYPE_DATASET) || + strchr(ds, '/') == NULL) { + (void) fprintf(stderr, gettext("-X %s: " + "not a valid non-root dataset name" + ".\n"), ds); + usage(B_FALSE); + } + excludes.list = safe_realloc(excludes.list, + sizeof (char *) * (excludes.count + 1)); + excludes.list[excludes.count++] = ds; + } break; case 'i': if (fromname) @@ -4541,7 +4506,7 @@ zfs_do_send(int argc, char **argv) if (flags.parsable && flags.verbosity == 0) flags.verbosity = 1; - if (exclude_context.count > 0 && !flags.replicate) { + if (excludes.count > 0 && !flags.replicate) { (void) fprintf(stderr, gettext("Cannot specify " "dataset exclusion (-X) on a non-recursive " "send.\n")); @@ -4730,10 +4695,8 @@ zfs_do_send(int argc, char **argv) flags.doall = B_TRUE; err = zfs_send(zhp, fromname, toname, &flags, STDOUT_FILENO, - exclude_context.count > 0 ? zfs_do_send_exclude : NULL, - &exclude_context, flags.verbosity >= 3 ? &dbgnv : NULL); - - free_dataset_excludes(&exclude_context); + excludes.count > 0 ? zfs_do_send_exclude : NULL, + &excludes, flags.verbosity >= 3 ? &dbgnv : NULL); if (flags.verbosity >= 3 && dbgnv != NULL) { /* @@ -4745,8 +4708,9 @@ zfs_do_send(int argc, char **argv) dump_nvlist(dbgnv, 0); nvlist_free(dbgnv); } - zfs_close(zhp); + zfs_close(zhp); + free(excludes.list); return (err != 0); } diff --git a/man/man8/zfs-send.8 b/man/man8/zfs-send.8 index 17e7294e9..70367f19d 100644 --- a/man/man8/zfs-send.8 +++ b/man/man8/zfs-send.8 @@ -39,8 +39,8 @@ .Sh SYNOPSIS .Nm zfs .Cm send -.Op Fl DLPRbcehnpsvw -.Op Fl X Ar dataset Ns Oo , Ns Ar dataset Oc Ns … +.Op Fl DLPbcehnpsvw +.Op Fl R Op Fl X Ar dataset Ns Oo , Ns Ar dataset Oc Ns … .Op Oo Fl I Ns | Ns Fl i Oc Ar snapshot .Ar snapshot .Nm zfs @@ -73,8 +73,8 @@ .It Xo .Nm zfs .Cm send -.Op Fl DLPRbcehnpvw -.Op Fl X Ar dataset Ns Oo , Ns Ar dataset Oc Ns … +.Op Fl DLPbcehnpsvw +.Op Fl R Op Fl X Ar dataset Ns Oo , Ns Ar dataset Oc Ns … .Op Oo Fl I Ns | Ns Fl i Oc Ar snapshot .Ar snapshot .Xc @@ -143,22 +143,15 @@ flag is used to send encrypted datasets, then .Fl w must also be specified. .It Fl X , -exclude Ar dataset Ns Oo , Ns Ar dataset Oc Ns … -When the -.Fl R -flag is given, +With +.Fl R , .Fl X -can be used to specify a list of datasets to be excluded from the -data stream. -The -.Fl X -option can be used multiple times, or the list of datasets can be -specified as a comma-separated list, or both. -.Ar dataset -must not be the pool's root dataset, and all descendant datasets of -.Ar dataset -will be excluded from the send stream. -Requires -.Fl R . +specifies a set of datasets (and, hence, their descendants), +to be excluded from the send stream. +The root dataset may not be excluded. +.Fl X Ar a Fl X Ar b +is equivalent to +.Fl X Ar a , Ns Ar b . .It Fl e , -embed Generate a more compact stream by using .Sy WRITE_EMBEDDED