Add basic reporting functions to libdevmapper.

WHATS_NEW_DM

@@ -1,5 +1,6 @@
 Version 1.02.15 -
 ===================================
+  Add basic reporting functions to libdevmapper.
   Fix a malloc error path in dmsetup message.
   More libdevmapper-event interface changes and fixes.
   Rename dm_saprintf() to dm_asprintf().

daemons/dmeventd/.exported_symbols

@@ -1,7 +1,7 @@
 dm_event_handler_create
 dm_event_handler_destroy
 dm_event_handler_set_dso
-dm_event_handler_set_devname
+dm_event_handler_set_dev_name
 dm_event_handler_set_uuid
 dm_event_handler_set_major
 dm_event_handler_set_minor

daemons/dmeventd/dmeventd.c

@@ -31,8 +31,10 @@
 #include <errno.h>
 #include <pthread.h>
 #include <sys/file.h>
+#include <sys/stat.h>
 #include <sys/wait.h>
-
+#include <sys/time.h>
+#include <sys/resource.h>
 #include <unistd.h>
 #include <arpa/inet.h>		/* for htonl, ntohl */
 

daemons/dmeventd/libdevmapper-event.c

@@ -33,7 +33,7 @@
 struct dm_event_handler {
 	const char *dso;
 
-	const char *devname;
+	const char *dev_name;
 
 	const char *uuid;
 	int major;
@@ -42,9 +42,9 @@ struct dm_event_handler {
 	enum dm_event_mask mask;
 };
 
-static void dm_event_handler_clear_devname(struct dm_event_handler *dmevh)
+static void dm_event_handler_clear_dev_name(struct dm_event_handler *dmevh)
 {
-	dmevh->devname = dmevh->uuid = NULL;
+	dmevh->dev_name = dmevh->uuid = NULL;
 	dmevh->major = dmevh->minor = 0;
 }
 
@@ -55,7 +55,7 @@ struct dm_event_handler *dm_event_handler_create(void)
 	if (!(dmevh = dm_malloc(sizeof(*dmevh))))
 		return NULL;
 
-	dmevh->dso = dmevh->devname = dmevh->uuid = NULL;
+	dmevh->dso = dmevh->dev_name = dmevh->uuid = NULL;
 	dmevh->major = dmevh->minor = 0;
 	dmevh->mask = 0;
 
@@ -72,16 +72,16 @@ void dm_event_handler_set_dso(struct dm_event_handler *dmevh, const char *path)
 	dmevh->dso = path;
 }
 
-void dm_event_handler_set_devname(struct dm_event_handler *dmevh, const char *devname)
+void dm_event_handler_set_dev_name(struct dm_event_handler *dmevh, const char *dev_name)
 {
-	dm_event_handler_clear_devname(dmevh);
+	dm_event_handler_clear_dev_name(dmevh);
 
-	dmevh->devname = devname;
+	dmevh->dev_name = dev_name;
 }
 
 void dm_event_handler_set_uuid(struct dm_event_handler *dmevh, const char *uuid)
 {
-	dm_event_handler_clear_devname(dmevh);
+	dm_event_handler_clear_dev_name(dmevh);
 
 	dmevh->uuid = uuid;
 }
@@ -90,7 +90,7 @@ void dm_event_handler_set_major(struct dm_event_handler *dmevh, int major)
 {
 	int minor = dmevh->minor;
 
-	dm_event_handler_clear_devname(dmevh);
+	dm_event_handler_clear_dev_name(dmevh);
 
 	dmevh->major = major;
 	dmevh->minor = minor;
@@ -100,7 +100,7 @@ void dm_event_handler_set_minor(struct dm_event_handler *dmevh, int minor)
 {
 	int major = dmevh->major;
 
-	dm_event_handler_clear_devname(dmevh);
+	dm_event_handler_clear_dev_name(dmevh);
 
 	dmevh->major = major;
 	dmevh->minor = minor;
@@ -117,9 +117,9 @@ const char *dm_event_handler_get_dso(const struct dm_event_handler *dmevh)
 	return dmevh->dso;
 }
 
-const char *dm_event_handler_get_devname(const struct dm_event_handler *dmevh)
+const char *dm_event_handler_get_dev_name(const struct dm_event_handler *dmevh)
 {
-	return dmevh->devname;
+	return dmevh->dev_name;
 }
 
 const char *dm_event_handler_get_uuid(const struct dm_event_handler *dmevh)
@@ -256,11 +256,11 @@ static int _daemon_write(struct dm_event_fifos *fifos,
 
 static int _daemon_talk(struct dm_event_fifos *fifos,
 			struct dm_event_daemon_message *msg, int cmd,
-			const char *dso_name, const char *devname,
+			const char *dso_name, const char *dev_name,
 			enum dm_event_mask evmask, uint32_t timeout)
 {
 	const char *dso = dso_name ? dso_name : "";
-	const char *dev = devname ? devname : "";
+	const char *dev = dev_name ? dev_name : "";
 	const char *fmt = "%s %s %u %" PRIu32;
 	memset(msg, 0, sizeof(*msg));
 
@@ -421,8 +421,8 @@ static struct dm_task *_get_device_info(const struct dm_event_handler *dmevh)
 
 	if (dmevh->uuid)
 		dm_task_set_uuid(dmt, dmevh->uuid);
-	else if (dmevh->devname)
+	else if (dmevh->dev_name)
-		dm_task_set_name(dmt, dmevh->devname);
+		dm_task_set_name(dmt, dmevh->dev_name);
 	else if (dmevh->major && dmevh->minor) {
 		dm_task_set_major(dmt, dmevh->major);
 		dm_task_set_minor(dmt, dmevh->minor);
@@ -453,7 +453,7 @@ failed:
 
 /* Handle the event (de)registration call and return negative error codes. */
 static int _do_event(int cmd, struct dm_event_daemon_message *msg,
-		    const char *dso_name, const char *devname,
+		    const char *dso_name, const char *dev_name,
 		    enum dm_event_mask evmask, uint32_t timeout)
 {
 	int ret;
@@ -464,7 +464,7 @@ static int _do_event(int cmd, struct dm_event_daemon_message *msg,
 		return -ESRCH;
 	}
 
-	ret = _daemon_talk(&fifos, msg, cmd, dso_name, devname, evmask, timeout);
+	ret = _daemon_talk(&fifos, msg, cmd, dso_name, dev_name, evmask, timeout);
 
 	/* what is the opposite of init? */
 	_dtr_client(&fifos);
@@ -553,12 +553,12 @@ static char *_fetch_string(char **src, const char delimiter)
 
 /* Parse a device message from the daemon. */
 static int _parse_message(struct dm_event_daemon_message *msg, char **dso_name,
-			 char **devname, enum dm_event_mask *evmask)
+			 char **dev_name, enum dm_event_mask *evmask)
 {
 	char *p = msg->data;
 
 	if ((*dso_name = _fetch_string(&p, ' ')) &&
-	    (*devname = _fetch_string(&p, ' '))) {
+	    (*dev_name = _fetch_string(&p, ' '))) {
 		*evmask = atoi(p);
 
 		return 0;

daemons/dmeventd/libdevmapper-event.h

@@ -59,9 +59,9 @@ void dm_event_handler_set_dso(struct dm_event_handler *dmevh, const char *path);
 
 /*
  * Identify the device to monitor by exactly one of
- * devname, uuid or device number.
+ * dev_name, uuid or device number.
  */
-void dm_event_handler_set_devname(struct dm_event_handler *dmevh, const char *devname);
+void dm_event_handler_set_dev_name(struct dm_event_handler *dmevh, const char *dev_name);
 
 void dm_event_handler_set_uuid(struct dm_event_handler *dmevh, const char *uuid);
 
@@ -75,7 +75,7 @@ void dm_event_handler_set_event_mask(struct dm_event_handler *dmevh,
 				     enum dm_event_mask evmask);
 
 const char *dm_event_handler_get_dso(const struct dm_event_handler *dmevh);
-const char *dm_event_handler_get_devname(const struct dm_event_handler *dmevh);
+const char *dm_event_handler_get_dev_name(const struct dm_event_handler *dmevh);
 const char *dm_event_handler_get_uuid(const struct dm_event_handler *dmevh);
 int dm_event_handler_get_major(const struct dm_event_handler *dmevh);
 int dm_event_handler_get_minor(const struct dm_event_handler *dmevh);
@@ -94,8 +94,8 @@ int dm_event_unregister_handler(const struct dm_event_handler *dmevh);
 /* Prototypes for DSO interface, see dmeventd.c, struct dso_data for
    detailed descriptions. */
 void process_event(struct dm_task *dmt, enum dm_event_mask evmask);
-int register_device(const char *devname, const char *uuid, int major, int minor);
+int register_device(const char *dev_name, const char *uuid, int major, int minor);
-int unregister_device(const char *devname, const char *uuid, int major,
+int unregister_device(const char *dev_name, const char *uuid, int major,
 		      int minor);
 
 #endif

libdm/.exported_symbols

@@ -116,3 +116,14 @@ dm_split_words
 dm_snprintf
 dm_basename
 dm_asprintf
+dm_report_init
+dm_report_object
+dm_report_output
+dm_report_free
+dm_report_get_private
+dm_report_field_string
+dm_report_field_int
+dm_report_field_int32
+dm_report_field_uint32
+dm_report_field_uint64
+dm_report_field_set_value

libdm/Makefile.in

@@ -24,6 +24,7 @@ SOURCES =\
 	libdm-file.c \
 	libdm-deptree.c \
 	libdm-string.c \
+	libdm-report.c \
 	mm/dbg_malloc.c \
 	mm/pool.c \
 	$(interface)/libdm-iface.c

libdm/libdevmapper.h

@@ -630,4 +630,81 @@ char *dm_basename(const char *path);
  */
 int dm_asprintf(char **buf, const char *format, ...);
 
+/*********************
+ * reporting functions
+ *********************/
+
+struct dm_report_object_type {
+	uint32_t id;			/* Powers of 2 */
+	const char *desc;
+	const char *prefix;		/* field id string prefix (optional) */
+	void *(*data_fn)(void *object);	/* callback from report_object() */
+};
+
+struct dm_report_field;
+
+/*
+ * dm_report_field_type flags
+ */
+#define DM_REPORT_FIELD_MASK		0x0000000F
+#define DM_REPORT_FIELD_ALIGN_LEFT	0x00000001
+#define DM_REPORT_FIELD_ALIGN_RIGHT	0x00000002
+#define DM_REPORT_FIELD_STRING		0x00000004
+#define DM_REPORT_FIELD_NUMBER		0x00000008
+
+struct dm_report;
+struct dm_report_field_type {
+	uint32_t type;		/* object type id */
+	const char id[32];	/* string used to specify the field */
+	unsigned int offset;	/* byte offset in the object */
+	const char heading[32];	/* string printed in header */
+	int width;		/* default width */
+	uint32_t flags;		/* DM_REPORT_FIELD_* */
+	int (*report_fn)(struct dm_report *rh, struct dm_pool *mem,
+			 struct dm_report_field *field, const void *data,
+			 void *private);
+};
+
+/*
+ * dm_report_init output_flags
+ */
+#define DM_REPORT_OUTPUT_MASK		0x00000007
+#define DM_REPORT_OUTPUT_ALIGNED	0x00000001
+#define DM_REPORT_OUTPUT_BUFFERED	0x00000002
+#define DM_REPORT_OUTPUT_HEADINGS	0x00000004
+
+struct dm_report *dm_report_init(uint32_t *report_types,
+				 const struct dm_report_object_type *types,
+				 const struct dm_report_field_type *fields,
+				 const char *output_fields,
+				 const char *output_separator,
+				 uint32_t output_flags,
+				 const char *sort_keys,
+				 void *private);
+int dm_report_object(struct dm_report *rh, void *object);
+int dm_report_output(struct dm_report *rh);
+void dm_report_free(struct dm_report *rh);
+
+/* report functions for common types */
+int dm_report_field_string(struct dm_report *rh, struct dm_pool *mem,
+			   struct dm_report_field *field, const void *data);
+int dm_report_field_int32(struct dm_report *rh, struct dm_pool *mem,
+			  struct dm_report_field *field, const void *data);
+int dm_report_field_uint32(struct dm_report *rh, struct dm_pool *mem,
+			   struct dm_report_field *field, const void *data);
+int dm_report_field_int(struct dm_report *rh, struct dm_pool *mem,
+			struct dm_report_field *field, const void *data);
+int dm_report_field_uint64(struct dm_report *rh, struct dm_pool *mem,
+			struct dm_report_field *field, const void *data);
+
+/*
+ * Helper function for custom reporting functions
+ */
+
+/*
+ * sortvalue may be NULL if it's the same as value
+ */
+void dm_report_field_set_value(struct dm_report_field *field,
+			       const void *value, const void *sortvalue);
+
 #endif				/* LIB_DEVICE_MAPPER_H */

libdm/libdm-report.c

@@ -0,0 +1,811 @@
+/*
+ * Copyright (C) 2002-2004 Sistina Software, Inc. All rights reserved.
+ * Copyright (C) 2004 Red Hat, Inc. All rights reserved.
+ *
+ * This file is part of device-mapper userspace tools.
+ * The code is based on LVM2 report function.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU General Public License v.2.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "libdevmapper.h"
+#include "list.h"
+#include "log.h"
+
+/*
+ * Internal flags
+ */
+#define RH_SORT_REQUIRED	0x00000100
+#define RH_HEADINGS_PRINTED	0x00000200
+
+struct dm_report {
+	struct dm_pool *mem;
+
+	uint32_t report_types;
+	const char *field_prefix;
+	uint32_t flags;
+	const char *separator;
+
+	uint32_t keys_count;
+
+	/* Ordered list of fields needed for this report */
+	struct list field_props;
+
+	/* Rows of report data */
+	struct list rows;
+
+	/* Array of field definitions */
+	const struct dm_report_field_type *fields;
+	const struct dm_report_object_type *types;
+
+	/* To store caller private data */
+	void *private;
+};
+
+/*
+ * Internal per-field flags
+ */
+#define FLD_HIDDEN	0x00000100
+#define FLD_SORT_KEY	0x00000200
+#define FLD_ASCENDING	0x00000400
+#define FLD_DESCENDING	0x00000800
+
+struct field_properties {
+	struct list list;
+	uint32_t field_num;
+	uint32_t sort_posn;
+	int width;
+	const struct dm_report_object_type *type;
+	uint32_t flags;
+};
+
+/*
+ * Report data field
+ */
+struct dm_report_field {
+	struct list list;
+	struct field_properties *props;
+
+	const char *report_string;	/* Formatted ready for display */
+	const void *sort_value;		/* Raw value for sorting */
+};
+
+struct row {
+	struct list list;
+	struct dm_report *rh;
+	struct list fields;			  /* Fields in display order */
+	struct dm_report_field *(*sort_fields)[]; /* Fields in sort order */
+};
+
+static const struct dm_report_object_type *_find_type(struct dm_report *rh,
+						      uint32_t report_type)
+{
+	const struct dm_report_object_type *t;
+
+	for (t = rh->types; t->data_fn; t++)
+		if (t->id == report_type)
+			return t;
+
+	return NULL;
+}
+
+/*
+ * Data-munging functions to prepare each data type for display and sorting
+ */
+
+int dm_report_field_string(struct dm_report *rh, struct dm_pool *mem,
+			   struct dm_report_field *field, const void *data)
+{
+	char *repstr;
+
+	if (!(repstr = dm_pool_strdup(rh->mem, *(const char **) data))) {
+		log_error("dm_report_field_string: dm_pool_strdup failed");
+		return 0;
+	}
+
+	field->report_string = repstr;
+	field->sort_value = (const void *) field->report_string;
+
+	return 1;
+}
+
+int dm_report_field_int(struct dm_report *rh, struct dm_pool *mem,
+			struct dm_report_field *field, const void *data)
+{
+	const int value = *(const int *) data;
+	uint64_t *sortval;
+	char *repstr;
+
+	if (!(repstr = dm_pool_zalloc(rh->mem, 13))) {
+		log_error("dm_report_field_int: dm_pool_alloc failed");
+		return 0;
+	}
+
+	if (!(sortval = dm_pool_alloc(rh->mem, sizeof(int64_t)))) {
+		log_error("dm_report_field_int: dm_pool_alloc failed");
+		return 0;
+	}
+
+	if (dm_snprintf(repstr, 12, "%d", value) < 0) {
+		log_error("dm_report_field_int: int too big: %d", value);
+		return 0;
+	}
+
+	*sortval = (const uint64_t) value;
+	field->sort_value = sortval;
+	field->report_string = repstr;
+
+	return 1;
+}
+
+int dm_report_field_uint32(struct dm_report *rh, struct dm_pool *mem,
+			   struct dm_report_field *field, const void *data)
+{
+	const uint32_t value = *(const uint32_t *) data;
+	uint64_t *sortval;
+	char *repstr;
+
+	if (!(repstr = dm_pool_zalloc(rh->mem, 12))) {
+		log_error("dm_report_field_uint32: dm_pool_alloc failed");
+		return 0;
+	}
+
+	if (!(sortval = dm_pool_alloc(rh->mem, sizeof(uint64_t)))) {
+		log_error("dm_report_field_uint32: dm_pool_alloc failed");
+		return 0;
+	}
+
+	if (dm_snprintf(repstr, 11, "%u", value) < 0) {
+		log_error("dm_report_field_uint32: uint32 too big: %u", value);
+		return 0;
+	}
+
+	*sortval = (const uint64_t) value;
+	field->sort_value = sortval;
+	field->report_string = repstr;
+
+	return 1;
+}
+
+int dm_report_field_int32(struct dm_report *rh, struct dm_pool *mem,
+			  struct dm_report_field *field, const void *data)
+{
+	const int32_t value = *(const int32_t *) data;
+	uint64_t *sortval;
+	char *repstr;
+
+	if (!(repstr = dm_pool_zalloc(rh->mem, 13))) {
+		log_error("dm_report_field_int32: dm_pool_alloc failed");
+		return 0;
+	}
+
+	if (!(sortval = dm_pool_alloc(rh->mem, sizeof(int64_t)))) {
+		log_error("dm_report_field_int32: dm_pool_alloc failed");
+		return 0;
+	}
+
+	if (dm_snprintf(repstr, 12, "%d", value) < 0) {
+		log_error("dm_report_field_int32: int32 too big: %d", value);
+		return 0;
+	}
+
+	*sortval = (const uint64_t) value;
+	field->sort_value = sortval;
+	field->report_string = repstr;
+
+	return 1;
+}
+
+int dm_report_field_uint64(struct dm_report *rh, struct dm_pool *mem,
+			   struct dm_report_field *field, const void *data)
+{
+	const int value = *(const uint64_t *) data;
+	uint64_t *sortval;
+	char *repstr;
+
+	if (!(repstr = dm_pool_zalloc(rh->mem, 22))) {
+		log_error("dm_report_field_uint64: dm_pool_alloc failed");
+		return 0;
+	}
+
+	if (!(sortval = dm_pool_alloc(rh->mem, sizeof(uint64_t)))) {
+		log_error("dm_report_field_uint64: dm_pool_alloc failed");
+		return 0;
+	}
+
+	if (dm_snprintf(repstr, 21, "%d", value) < 0) {
+		log_error("dm_report_field_uint64: uint64 too big: %d", value);
+		return 0;
+	}
+
+	*sortval = (const uint64_t) value;
+	field->sort_value = sortval;
+	field->report_string = repstr;
+
+	return 1;
+}
+
+/*
+ * Helper functions for custom report functions
+ */
+void dm_report_field_set_value(struct dm_report_field *field, const void *value, const void *sortvalue)
+{
+	field->report_string = (const char *) value;
+	field->sort_value = sortvalue ? : value;
+}
+
+/*
+ * show help message
+ */
+static void _display_fields(struct dm_report *rh)
+{
+	uint32_t f;
+	const struct dm_report_object_type *type;
+	const char *desc, *last_desc = "";
+
+	for (f = 0; rh->fields[f].report_fn; f++) {
+		if ((type = _find_type(rh, rh->fields[f].type)) && type->desc)
+			desc = type->desc;
+		else
+			desc = " ";
+		if (desc != last_desc) {
+			if (*last_desc)
+				log_print(" ");
+			log_print("%s Fields", desc);
+		}
+
+		log_print("- %s", rh->fields[f].id);
+		last_desc = desc;
+	}
+}
+
+/*
+ * Initialise report handle
+ */
+static int _copy_field(struct dm_report *rh, struct field_properties *dest,
+		       uint32_t field_num)
+{
+	dest->field_num = field_num;
+	dest->width = rh->fields[field_num].width;
+	dest->flags = rh->fields[field_num].flags & DM_REPORT_FIELD_MASK;
+
+	/* set object type method */
+	dest->type = _find_type(rh, rh->fields[field_num].type);
+	if (!dest->type) {
+		log_error("dm_report: field not match: %s",
+			  rh->fields[field_num].id);
+		return 0;
+	}
+
+	return 1;
+}
+
+static int _field_match(struct dm_report *rh, const char *field, size_t flen)
+{
+	uint32_t f, l;
+	struct field_properties *fp;
+
+	if (!flen)
+		return 0;
+
+	for (f = 0; rh->fields[f].report_fn; f++) {
+		if ((!strncasecmp(rh->fields[f].id, field, flen) &&
+		     strlen(rh->fields[f].id) == flen) ||
+		    (l = strlen(rh->field_prefix),
+		     !strncasecmp(rh->field_prefix, rh->fields[f].id, l) &&
+		     !strncasecmp(rh->fields[f].id + l, field, flen) &&
+		     strlen(rh->fields[f].id) == l + flen)) {
+			rh->report_types |= rh->fields[f].type;
+			if (!(fp = dm_pool_zalloc(rh->mem, sizeof(*fp)))) {
+				log_error("dm_report: "
+					  "struct field_properties allocation "
+					  "failed");
+				return 0;
+			}
+			if (!_copy_field(rh, fp, f))
+				return 0;
+
+			list_add(&rh->field_props, &fp->list);
+			return 1;
+		}
+	}
+
+	return 0;
+}
+
+static int _add_sort_key(struct dm_report *rh, uint32_t field_num,
+			 uint32_t flags)
+{
+	struct field_properties *fp, *found = NULL;
+
+	list_iterate_items(fp, &rh->field_props) {
+		if (fp->field_num == field_num) {
+			found = fp;
+			break;
+		}
+	}
+
+	if (!found) {
+		rh->report_types |= rh->fields[field_num].type;
+		if (!(found = dm_pool_zalloc(rh->mem, sizeof(*found)))) {
+			log_error("dm_report: "
+				  "struct field_properties allocation failed");
+			return 0;
+		}
+		if (!_copy_field(rh, found, field_num))
+			return 0;
+
+		/* Add as a non-display field */
+		found->flags |= FLD_HIDDEN;
+
+		list_add(&rh->field_props, &found->list);
+	}
+
+	if (found->flags & FLD_SORT_KEY) {
+		log_error("dm_report: Ignoring duplicate sort field: %s",
+			  rh->fields[field_num].id);
+		return 1;
+	}
+
+	found->flags |= FLD_SORT_KEY;
+	found->sort_posn = rh->keys_count++;
+	found->flags |= flags;
+
+	return 1;
+}
+
+static int _key_match(struct dm_report *rh, const char *key, size_t len)
+{
+	uint32_t f, l;
+	uint32_t flags;
+
+	if (!len)
+		return 0;
+
+	if (*key == '+') {
+		key++;
+		len--;
+		flags = FLD_ASCENDING;
+	} else if (*key == '-') {
+		key++;
+		len--;
+		flags = FLD_DESCENDING;
+	} else
+		flags = FLD_ASCENDING;
+
+	if (!len) {
+		log_error("dm_report: Missing sort field name");
+		return 0;
+	}
+
+	for (f = 0; rh->fields[f].report_fn; f++) {
+		if ((!strncasecmp(rh->fields[f].id, key, len) &&
+		     strlen(rh->fields[f].id) == len) ||
+		    (l = strlen(rh->field_prefix),
+		     !strncasecmp(rh->field_prefix, rh->fields[f].id, l) &&
+		     !strncasecmp(rh->fields[f].id + l, key, len) &&
+		     strlen(rh->fields[f].id) == l + len)) {
+			return _add_sort_key(rh, f, flags);
+		}
+	}
+
+	return 0;
+}
+
+static int _parse_options(struct dm_report *rh, const char *format)
+{
+	const char *ws;		/* Word start */
+	const char *we = format;	/* Word end */
+
+	while (*we) {
+		/* Allow consecutive commas */
+		while (*we && *we == ',')
+			we++;
+
+		/* start of the field name */
+		ws = we;
+		while (*we && *we != ',')
+			we++;
+
+		if (!_field_match(rh, ws, (size_t) (we - ws))) {
+			_display_fields(rh);
+			log_print(" ");
+			log_error("dm_report: Unrecognised field: %.*s",
+				  (int) (we - ws), ws);
+			return 0;
+		}
+	}
+
+	return 1;
+}
+
+static int _parse_keys(struct dm_report *rh, const char *keys)
+{
+	const char *ws;		/* Word start */
+	const char *we = keys;	/* Word end */
+
+	while (*we) {
+		/* Allow consecutive commas */
+		while (*we && *we == ',')
+			we++;
+		ws = we;
+		while (*we && *we != ',')
+			we++;
+		if (!_key_match(rh, ws, (size_t) (we - ws))) {
+			log_error("dm_report: Unrecognised field: %.*s",
+				  (int) (we - ws), ws);
+			return 0;
+		}
+	}
+
+	return 1;
+}
+
+struct dm_report *dm_report_init(uint32_t *report_types,
+				 const struct dm_report_object_type *types,
+				 const struct dm_report_field_type *fields,
+				 const char *output_fields,
+				 const char *output_separator,
+				 uint32_t output_flags,
+				 const char *sort_keys,
+				 void *private)
+{
+	struct dm_report *rh;
+	const struct dm_report_object_type *type;
+
+	if (!(rh = dm_malloc(sizeof(*rh)))) {
+		log_error("dm_report_init: dm_malloc failed");
+		return 0;
+	}
+	memset(rh, 0, sizeof(*rh));
+
+	/*
+	 * rh->report_types is updated in _parse_options() and _parse_keys()
+	 * to contain all types corresponding to the fields specified by
+	 * options or keys.
+	 */
+	if (report_types)
+		rh->report_types = *report_types;
+
+	rh->separator = output_separator;
+	rh->fields = fields;
+	rh->types = types;
+	rh->private = private;
+
+	rh->flags |= output_flags & DM_REPORT_OUTPUT_MASK;
+
+	if (output_flags & DM_REPORT_OUTPUT_BUFFERED)
+		rh->flags |= RH_SORT_REQUIRED;
+
+	list_init(&rh->field_props);
+	list_init(&rh->rows);
+
+	if ((type = _find_type(rh, rh->report_types)) && type->prefix)
+		rh->field_prefix = type->prefix;
+	else
+		rh->field_prefix = "";
+
+	if (!(rh->mem = dm_pool_create("report", 10 * 1024))) {
+		log_error("dm_report_init: allocation of memory pool failed");
+		return NULL;
+	}
+
+	/* Generate list of fields for output based on format string & flags */
+	if (!_parse_options(rh, output_fields))
+		return NULL;
+
+	if (!_parse_keys(rh, sort_keys))
+		return NULL;
+
+	/* Return updated types value for further compatility check by caller */
+	if (report_types)
+		*report_types = rh->report_types;
+
+	return rh;
+}
+
+void dm_report_free(struct dm_report *rh)
+{
+	dm_pool_destroy(rh->mem);
+	dm_free(rh);
+}
+
+/*
+ * Create a row of data for an object
+ */
+static void * _report_get_field_data(struct dm_report *rh,
+			      struct field_properties *fp, void *object)
+{
+	void *ret = fp->type->data_fn(object);
+
+	if (!ret)
+		return NULL;
+
+	return ret + rh->fields[fp->field_num].offset;
+}
+
+int dm_report_object(struct dm_report *rh, void *object)
+{
+	struct field_properties *fp;
+	struct row *row;
+	struct dm_report_field *field;
+	void *data = NULL;
+
+	if (!(row = dm_pool_zalloc(rh->mem, sizeof(*row)))) {
+		log_error("dm_report_object: struct row allocation failed");
+		return 0;
+	}
+
+	row->rh = rh;
+
+	if ((rh->flags & RH_SORT_REQUIRED) &&
+	    !(row->sort_fields =
+		dm_pool_zalloc(rh->mem, sizeof(struct dm_report_field *) *
+			       rh->keys_count))) {
+		log_error("dm_report_object: "
+			  "row sort value structure allocation failed");
+		return 0;
+	}
+
+	list_init(&row->fields);
+	list_add(&rh->rows, &row->list);
+
+	/* For each field to be displayed, call its report_fn */
+	list_iterate_items(fp, &rh->field_props) {
+		if (!(field = dm_pool_zalloc(rh->mem, sizeof(*field)))) {
+			log_error("dm_report_object: "
+				  "struct dm_report_field allocation failed");
+			return 0;
+		}
+		field->props = fp;
+
+		data = _report_get_field_data(rh, fp, object);
+		if (!data)
+			return 0;
+
+		if (!rh->fields[fp->field_num].report_fn(rh, rh->mem,
+							 field, data,
+							 rh->private)) {
+			log_error("dm_report_object: "
+				  "report function failed for field %s",
+				  rh->fields[fp->field_num].id);
+			return 0;
+		}
+
+		if ((strlen(field->report_string) > field->props->width))
+			field->props->width = strlen(field->report_string);
+
+		if ((rh->flags & RH_SORT_REQUIRED) &&
+		    (field->props->flags & FLD_SORT_KEY)) {
+			(*row->sort_fields)[field->props->sort_posn] = field;
+		}
+		list_add(&row->fields, &field->list);
+	}
+
+	if (!(rh->flags & DM_REPORT_OUTPUT_BUFFERED))
+		return dm_report_output(rh);
+
+	return 1;
+}
+
+/*
+ * Print row of headings
+ */
+static int _report_headings(struct dm_report *rh)
+{
+	struct field_properties *fp;
+	const char *heading;
+	char buf[1024];
+
+	if (rh->flags & RH_HEADINGS_PRINTED)
+		return 1;
+
+	rh->flags |= RH_HEADINGS_PRINTED;
+
+	if (!(rh->flags & DM_REPORT_OUTPUT_HEADINGS))
+		return 1;
+
+	if (!dm_pool_begin_object(rh->mem, 128)) {
+		log_error("dm_report: "
+			  "dm_pool_begin_object failed for headings");
+		return 0;
+	}
+
+	/* First heading line */
+	list_iterate_items(fp, &rh->field_props) {
+		if (fp->flags & FLD_HIDDEN)
+			continue;
+
+		heading = rh->fields[fp->field_num].heading;
+		if (rh->flags & DM_REPORT_OUTPUT_ALIGNED) {
+			if (dm_snprintf(buf, sizeof(buf), "%-*.*s",
+					 fp->width, fp->width, heading) < 0) {
+				log_error("dm_report: snprintf heading failed");
+				goto bad;
+			}
+			if (!dm_pool_grow_object(rh->mem, buf, fp->width)) {
+				log_error("dm_report: Failed to generate report headings for printing");
+				goto bad;
+			}
+		} else if (!dm_pool_grow_object(rh->mem, heading,
+						strlen(heading))) {
+			log_error("dm_report: Failed to generate report headings for printing");
+			goto bad;
+		}
+
+		if (!list_end(&rh->field_props, &fp->list))
+			if (!dm_pool_grow_object(rh->mem, rh->separator,
+					      strlen(rh->separator))) {
+				log_error("dm_report: Failed to generate report headings for printing");
+				goto bad;
+			}
+	}
+	if (!dm_pool_grow_object(rh->mem, "\0", 1)) {
+		log_error("dm_report: Failed to generate report headings for printing");
+		goto bad;
+	}
+	log_print("%s", (char *) dm_pool_end_object(rh->mem));
+
+	return 1;
+
+      bad:
+	dm_pool_abandon_object(rh->mem);
+	return 0;
+}
+
+/*
+ * Sort rows of data
+ */
+static int _row_compare(const void *a, const void *b)
+{
+	const struct row *rowa = *(const struct row **) a;
+	const struct row *rowb = *(const struct row **) b;
+	const struct dm_report_field *sfa, *sfb;
+	int32_t cnt = -1;
+
+	for (cnt = 0; cnt < rowa->rh->keys_count; cnt++) {
+		sfa = (*rowa->sort_fields)[cnt];
+		sfb = (*rowb->sort_fields)[cnt];
+		if (sfa->props->flags & DM_REPORT_FIELD_NUMBER) {
+			const uint64_t numa =
+			    *(const uint64_t *) sfa->sort_value;
+			const uint64_t numb =
+			    *(const uint64_t *) sfb->sort_value;
+
+			if (numa == numb)
+				continue;
+
+			if (sfa->props->flags & FLD_ASCENDING) {
+				return (numa > numb) ? 1 : -1;
+			} else {	/* FLD_DESCENDING */
+				return (numa < numb) ? 1 : -1;
+			}
+		} else {	/* DM_REPORT_FIELD_STRING */
+			const char *stra = (const char *) sfa->sort_value;
+			const char *strb = (const char *) sfb->sort_value;
+			int cmp = strcmp(stra, strb);
+
+			if (!cmp)
+				continue;
+
+			if (sfa->props->flags & FLD_ASCENDING) {
+				return (cmp > 0) ? 1 : -1;
+			} else {	/* FLD_DESCENDING */
+				return (cmp < 0) ? 1 : -1;
+			}
+		}
+	}
+
+	return 0;		/* Identical */
+}
+
+static int _sort_rows(struct dm_report *rh)
+{
+	struct row *(*rows)[];
+	uint32_t count = 0;
+	struct row *row;
+
+	if (!(rows = dm_pool_alloc(rh->mem, sizeof(**rows) *
+				list_size(&rh->rows)))) {
+		log_error("dm_report: sort array allocation failed");
+		return 0;
+	}
+
+	list_iterate_items(row, &rh->rows)
+		(*rows)[count++] = row;
+
+	qsort(rows, count, sizeof(**rows), _row_compare);
+
+	list_init(&rh->rows);
+	while (count--)
+		list_add_h(&rh->rows, &(*rows)[count]->list);
+
+	return 1;
+}
+
+/*
+ * Produce report output
+ */
+int dm_report_output(struct dm_report *rh)
+{
+	struct list *fh, *rowh, *ftmp, *rtmp;
+	struct row *row = NULL;
+	struct dm_report_field *field;
+	const char *repstr;
+	char buf[4096];
+	int width;
+
+	if (list_empty(&rh->rows))
+		return 1;
+
+	/* Sort rows */
+	if ((rh->flags & RH_SORT_REQUIRED))
+		_sort_rows(rh);
+
+	/* If headings not printed yet, calculate field widths and print them */
+	if (!(rh->flags & RH_HEADINGS_PRINTED))
+		_report_headings(rh);
+
+	/* Print and clear buffer */
+	list_iterate_safe(rowh, rtmp, &rh->rows) {
+		if (!dm_pool_begin_object(rh->mem, 512)) {
+			log_error("dm_report: "
+				  "dm_pool_begin_object failed for row");
+			return 0;
+		}
+		row = list_item(rowh, struct row);
+		list_iterate_safe(fh, ftmp, &row->fields) {
+			field = list_item(fh, struct dm_report_field);
+			if (field->props->flags & FLD_HIDDEN)
+				continue;
+
+			repstr = field->report_string;
+			width = field->props->width;
+			if (!(rh->flags & DM_REPORT_OUTPUT_ALIGNED)) {
+				if (!dm_pool_grow_object(rh->mem, repstr,
+						      strlen(repstr)))
+					goto bad_grow;
+			} else if (field->props->flags & DM_REPORT_FIELD_ALIGN_LEFT) {
+				if (dm_snprintf(buf, sizeof(buf), "%-*.*s",
+						 width, width, repstr) < 0)
+					goto bad_snprintf;
+				if (!dm_pool_grow_object(rh->mem, buf, width))
+					goto bad_grow;
+			} else if (field->props->flags & DM_REPORT_FIELD_ALIGN_RIGHT) {
+				if (dm_snprintf(buf, sizeof(buf), "%*.*s",
+						 width, width, repstr) < 0)
+					goto bad_snprintf;
+				if (!dm_pool_grow_object(rh->mem, buf, width))
+					goto bad_grow;
+			}
+
+			if (!list_end(&row->fields, fh))
+				if (!dm_pool_grow_object(rh->mem, rh->separator,
+						      strlen(rh->separator)))
+					goto bad_grow;
+			list_del(&field->list);
+		}
+		if (!dm_pool_grow_object(rh->mem, "\0", 1))
+			goto bad_grow;
+		log_print("%s", (char *) dm_pool_end_object(rh->mem));
+		list_del(&row->list);
+	}
+
+	if (row)
+		dm_pool_free(rh->mem, row);
+
+	return 1;
+
+      bad_snprintf:
+	log_error("dm_report: snprintf row failed");
+      bad_grow:
+	log_error("dm_report: Failed to generate row for printing");
+	dm_pool_abandon_object(rh->mem);
+	return 0;
+}