Set process title during zfs send.

This adds a '-V' option to 'zfs send', which sets the process title once a
second to the progress information.

This code has been in FreeNAS for a long time now; this is just upstreaming
it here.  It was originially written by delphij.

Reviewed by:	mav
Obtained from:	iXsystems, Inc
Sponsored by:	iXsystems, Inc
Differential Revision:	https://reviews.freebsd.org/D19184

cddl/contrib/opensolaris/cmd/zfs/zfs.8

@@ -32,7 +32,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd August 11, 2018
+.Dd February 15, 2018
 .Dt ZFS 8
 .Os
 .Sh NAME
@@ -184,7 +184,7 @@
 .Ar bookmark
 .Nm
 .Cm send
-.Op Fl DLPRcenpv
+.Op Fl DLPRVcenpv
 .Op Fl i Ar snapshot | Fl I Ar snapshot
 .Ar snapshot
 .Nm
@@ -194,7 +194,7 @@
 .Ar filesystem Ns | Ns Ar volume Ns | Ns Ar snapshot
 .Nm
 .Cm send
-.Op Fl Penv
+.Op Fl PVenv
 .Fl t Ar receive_resume_token
 .Nm
 .Cm receive Ns | Ns Cm recv
@@ -2607,7 +2607,7 @@ feature.
 .It Xo
 .Nm
 .Cm send
-.Op Fl DLPRcenpv
+.Op Fl DLPRVcenpv
 .Op Fl i Ar snapshot | Fl I Ar snapshot
 .Ar snapshot
 .Xc
@@ -2753,6 +2753,8 @@ Print machine-parsable verbose information about the stream package generated.
 .It Fl v, -verbose
 Print verbose information about the stream package generated.
 This information includes a per-second report of how much data has been sent.
+.It Fl V
+Set the process title to a per-second report of how much data has been sent.
 .El
 .Pp
 The format of the stream is committed. You will be able to receive your streams

cddl/contrib/opensolaris/cmd/zfs/zfs_main.c

@@ -3813,7 +3813,7 @@ zfs_do_send(int argc, char **argv)
 	};
 
 	/* check options */
-	while ((c = getopt_long(argc, argv, ":i:I:RbDpvnPLet:c", long_options,
+	while ((c = getopt_long(argc, argv, ":i:I:RbDpVvnPLet:c", long_options,
 	    NULL)) != -1) {
 		switch (c) {
 		case 'i':
@@ -3837,6 +3837,10 @@ zfs_do_send(int argc, char **argv)
 			flags.parsable = B_TRUE;
 			flags.verbose = B_TRUE;
 			break;
+		case 'V':
+			flags.progress = B_TRUE;
+			flags.progressastitle = B_TRUE;
+			break;
 		case 'v':
 			if (flags.verbose)
 				extraverbose = B_TRUE;

cddl/contrib/opensolaris/lib/libzfs/common/libzfs.h

@@ -651,6 +651,9 @@ typedef struct sendflags {
 
 	/* compressed WRITE records are permitted */
 	boolean_t compress;
+
+	/* show progress as process title(ie. -V) */
+	boolean_t progressastitle;
 } sendflags_t;
 
 typedef boolean_t (snapfilter_cb_t)(zfs_handle_t *, void *);

cddl/contrib/opensolaris/lib/libzfs/common/libzfs_sendrecv.c

@@ -85,6 +85,8 @@ typedef struct progress_arg {
 	zfs_handle_t *pa_zhp;
 	int pa_fd;
 	boolean_t pa_parsable;
+	boolean_t pa_astitle;
+	uint64_t pa_size;
 } progress_arg_t;
 
 typedef struct dataref {
@@ -930,6 +932,7 @@ typedef struct send_dump_data {
 	uint64_t prevsnap_obj;
 	boolean_t seenfrom, seento, replicate, doall, fromorigin;
 	boolean_t verbose, dryrun, parsable, progress, embed_data, std_out;
+	boolean_t progressastitle;
 	boolean_t large_block, compress;
 	int outfd;
 	boolean_t err;
@@ -1110,14 +1113,14 @@ send_progress_thread(void *arg)
 	zfs_cmd_t zc = { 0 };
 	zfs_handle_t *zhp = pa->pa_zhp;
 	libzfs_handle_t *hdl = zhp->zfs_hdl;
-	unsigned long long bytes;
+	unsigned long long bytes, total;
 	char buf[16];
 	time_t t;
 	struct tm *tm;
 
 	(void) strlcpy(zc.zc_name, zhp->zfs_name, sizeof (zc.zc_name));
 
-	if (!pa->pa_parsable)
+	if (!pa->pa_parsable && !pa->pa_astitle)
 		(void) fprintf(stderr, "TIME        SENT   SNAPSHOT\n");
 
 	/*
@@ -1134,7 +1137,16 @@ send_progress_thread(void *arg)
 		tm = localtime(&t);
 		bytes = zc.zc_cookie;
 
-		if (pa->pa_parsable) {
+		if (pa->pa_astitle) {
+			int pct;
+			if (pa->pa_size > bytes)
+				pct = 100 * bytes / pa->pa_size;
+			else
+				pct = 100;
+
+			setproctitle("sending %s (%d%%: %llu/%llu)",
+			    zhp->zfs_name, pct, bytes, pa->pa_size);
+		} else if (pa->pa_parsable) {
 			(void) fprintf(stderr, "%02d:%02d:%02d\t%llu\t%s\n",
 			    tm->tm_hour, tm->tm_min, tm->tm_sec,
 			    bytes, zhp->zfs_name);
@@ -1204,6 +1216,7 @@ dump_snapshot(zfs_handle_t *zhp, void *arg)
 	boolean_t isfromsnap, istosnap, fromorigin;
 	boolean_t exclude = B_FALSE;
 	FILE *fout = sdd->std_out ? stdout : stderr;
+	uint64_t size = 0;
 
 	err = 0;
 	thissnap = strchr(zhp->zfs_name, '@') + 1;
@@ -1278,15 +1291,16 @@ dump_snapshot(zfs_handle_t *zhp, void *arg)
 	fromorigin = sdd->prevsnap[0] == '\0' &&
 	    (sdd->fromorigin || sdd->replicate);
 
-	if (sdd->verbose) {
+	if (sdd->progress && sdd->dryrun) {
-		uint64_t size = 0;
 		(void) estimate_ioctl(zhp, sdd->prevsnap_obj,
 		    fromorigin, flags, &size);
+		sdd->size += size;
+	}
 
+	if (sdd->verbose) {
 		send_print_verbose(fout, zhp->zfs_name,
 		    sdd->prevsnap[0] ? sdd->prevsnap : NULL,
 		    size, sdd->parsable);
-		sdd->size += size;
 	}
 
 	if (!sdd->dryrun) {
@@ -1298,6 +1312,8 @@ dump_snapshot(zfs_handle_t *zhp, void *arg)
 			pa.pa_zhp = zhp;
 			pa.pa_fd = sdd->outfd;
 			pa.pa_parsable = sdd->parsable;
+			pa.pa_size = sdd->size;
+			pa.pa_astitle = sdd->progressastitle;
 
 			if ((err = pthread_create(&tid, NULL,
 			    send_progress_thread, &pa)) != 0) {
@@ -1580,6 +1596,7 @@ zfs_send_resume(libzfs_handle_t *hdl, sendflags_t *flags, int outfd,
 	int error = 0;
 	char name[ZFS_MAX_DATASET_NAME_LEN];
 	enum lzc_send_flags lzc_flags = 0;
+	uint64_t size = 0;
 	FILE *fout = (flags->verbose && flags->dryrun) ? stdout : stderr;
 
 	(void) snprintf(errbuf, sizeof (errbuf), dgettext(TEXT_DOMAIN,
@@ -1648,12 +1665,13 @@ zfs_send_resume(libzfs_handle_t *hdl, sendflags_t *flags, int outfd,
 		fromname = name;
 	}
 
-	if (flags->verbose) {
+	if (flags->progress) {
-		uint64_t size = 0;
 		error = lzc_send_space(zhp->zfs_name, fromname,
 		    lzc_flags, &size);
 		if (error == 0)
 			size = MAX(0, (int64_t)(size - bytes));
+	}
+	if (flags->verbose) {
 		send_print_verbose(fout, zhp->zfs_name, fromname,
 		    size, flags->parsable);
 	}
@@ -1669,6 +1687,8 @@ zfs_send_resume(libzfs_handle_t *hdl, sendflags_t *flags, int outfd,
 			pa.pa_zhp = zhp;
 			pa.pa_fd = outfd;
 			pa.pa_parsable = flags->parsable;
+			pa.pa_size = size;
+			pa.pa_astitle = flags->progressastitle;
 
 			error = pthread_create(&tid, NULL,
 			    send_progress_thread, &pa);
@@ -1878,6 +1898,7 @@ zfs_send(zfs_handle_t *zhp, const char *fromsnap, const char *tosnap,
 	sdd.verbose = flags->verbose;
 	sdd.parsable = flags->parsable;
 	sdd.progress = flags->progress;
+	sdd.progressastitle = flags->progressastitle;
 	sdd.dryrun = flags->dryrun;
 	sdd.large_block = flags->largeblock;
 	sdd.embed_data = flags->embed_data;
@@ -1914,7 +1935,7 @@ zfs_send(zfs_handle_t *zhp, const char *fromsnap, const char *tosnap,
 		sdd.cleanup_fd = -1;
 		sdd.snapholds = NULL;
 	}
-	if (flags->verbose || sdd.snapholds != NULL) {
+	if (flags->progress || sdd.snapholds != NULL) {
 		/*
 		 * Do a verbose no-op dry run to get all the verbose output
 		 * or to gather snapshot hold's before generating any data,