Add get-allocated-inos scoutfs command

Add the get-allocated-inos scoutfs command which wraps the
GET_ALLOCATED_INOS ioctl.   It'll be used by tests to find items
associated with an inode instead of trying to open the inode by a
constructed handle after it was unlinked.

Signed-off-by: Zach Brown <zab@versity.com>

utils/man/scoutfs.8

@@ -617,6 +617,33 @@ command is used first.
 .RE
 .PD
 
+.TP
+.BI "get-allocated-inos [-i|--ino INO] [-s|--single] [-p|--path PATH]"
+.sp
+This debugging command prints allocated inode numbers.  It only prints
+inodes
+found in the group that contains the starting inode.  The printed inode
+numbers aren't necessarily reachable.  They could be anywhere in the
+process from being unlinked to finally deleted when their items
+were found.
+.RS 1.0i
+.PD 0
+.TP
+.sp
+.B "-i, --ino INO"
+The first 64bit inode number which could be printed.
+.TP
+.B "-s, --single"
+Only print the single starting inode when it is allocated, all other allocated
+inode numbers will be ignored.
+.TP
+.B "-p, --path PATH"
+A path within a ScoutFS filesystem.
+.RE
+.PD
+
+.TP
+
 .SH SEE ALSO
 .BR scoutfs (5),
 .BR xattr (7),

utils/src/get_allocated_inos.c

@@ -0,0 +1,137 @@
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/ioctl.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <string.h>
+#include <argp.h>
+
+#include "sparse.h"
+#include "parse.h"
+#include "util.h"
+#include "format.h"
+#include "ioctl.h"
+#include "cmd.h"
+
+struct get_allocated_inos_args {
+	char *path;
+	u64 ino;
+	bool have_ino;
+	bool single;
+};
+
+static int do_get_allocated_inos(struct get_allocated_inos_args *args)
+{
+	struct scoutfs_ioctl_get_allocated_inos gai;
+	u64 *inos = NULL;
+	int fd = -1;
+	u64 bytes;
+	int ret;
+	int i;
+
+	if (args->single)
+		bytes = sizeof(*inos);
+	else
+		bytes = SCOUTFS_LOCK_INODE_GROUP_NR * sizeof(*inos);
+
+	inos = malloc(bytes);
+	if (!inos) {
+		fprintf(stderr, "inode number array allocation failed\n");
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	fd = get_path(args->path, O_RDONLY);
+	if (fd < 0)
+		return fd;
+
+	memset(&gai, 0, sizeof(gai));
+	gai.start_ino = args->ino;
+	gai.inos_ptr = (unsigned long)inos;
+	gai.inos_bytes = bytes;
+
+	ret = ioctl(fd, SCOUTFS_IOC_GET_ALLOCATED_INOS, &gai);
+	if (ret < 0) {
+		ret = -errno;
+		fprintf(stderr, "get_allocated_inos ioctl failed: "
+			"%s (%d)\n", strerror(errno), errno);
+		goto out;
+	}
+
+	if (args->single && ret > 0 && inos[0] != args->ino)
+		ret = 0;
+
+	for (i = 0; i < ret; i++)
+		printf("%llu\n", inos[i]);
+
+	ret = 0;
+out:
+	if (fd >= 0)
+		close(fd);
+	free(inos);
+
+	return ret;
+};
+
+static int parse_opt(int key, char *arg, struct argp_state *state)
+{
+	struct get_allocated_inos_args *args = state->input;
+	int ret;
+
+	switch (key) {
+	case 'i':
+		ret = parse_u64(arg, &args->ino);
+		if (ret)
+			return ret;
+		args->have_ino = true;
+	case 'p':
+		args->path = strdup_or_error(state, arg);
+		break;
+	case 's':
+		args->single = true;
+		break;
+	case ARGP_KEY_FINI:
+		if (!args->have_ino)
+			argp_error(state, "must provide --ino starting inode number option");
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static struct argp_option options[] = {
+	{ "ino", 'i', "NUMBER", 0, "Start from 64bit inode number (required)"},
+	{ "path", 'p', "PATH", 0, "Path to ScoutFS filesystem"},
+	{ "single", 's', NULL, 0, "Only print single specific inode number argument"},
+	{ NULL }
+};
+
+static struct argp argp = {
+	options,
+	parse_opt,
+	NULL,
+	"Print allocated inode numbers from starting inode number"
+};
+
+static int get_allocated_inos_cmd(int argc, char **argv)
+{
+
+	struct get_allocated_inos_args get_allocated_inos_args = {NULL};
+	int ret;
+
+	ret = argp_parse(&argp, argc, argv, 0, NULL, &get_allocated_inos_args);
+	if (ret)
+		return ret;
+
+	return do_get_allocated_inos(&get_allocated_inos_args);
+}
+
+static void __attribute__((constructor)) get_allocated_inos_ctor(void)
+{
+	cmd_register_argp("get-allocated-inos", &argp, GROUP_DEBUG, get_allocated_inos_cmd);
+}