MFC r332436, r332440

r332436:
 Add the ability to specify absolute and relative offsets to size partitions.

 To create hybrid boot media we want to specify a partition at a known location.
 This extends the syntax of size partitions to include an optional offset that
 can be absolute or relative. It also introduces validation to make sure that
 this hasn't resulted in overlapping partitions. I haven't added this to the
 file and process partition specifications yet but the mechanics are designed
 such that if someone comes up with a good way of specifying the offset it
 will be fairly easy to add in.

r332440:
 Fix a conditional that got mucked up.

Sponsored by:	iXsystems, Inc.

2 files changed, 104 insertions, 21 deletions

diff --git a/usr.bin/mkimg/mkimg.c b/usr.bin/mkimg/mkimg.c
index 51b22c7..c5a85aa 100644
--- a/usr.bin/mkimg/mkimg.c
+++ b/usr.bin/mkimg/mkimg.c
@@ -35,6 +35,7 @@ __FBSDID("$FreeBSD$");
 #include <getopt.h>
 #include <libutil.h>
 #include <limits.h>
+#include <stdbool.h>
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -170,13 +171,14 @@ usage(const char *why)
 	print_schemes(1);
 	fputc('\n', stderr);
 	fprintf(stderr, "    partition specification:\n");
-	fprintf(stderr, "\t<t>[/<l>]::<size>\t-  empty partition of given "
-	    "size\n");
-	fprintf(stderr, "\t<t>[/<l>]:=<file>\t-  partition content and size "
-	    "are determined\n\t\t\t\t   by the named file\n");
-	fprintf(stderr, "\t<t>[/<l>]:-<cmd>\t-  partition content and size "
-	    "are taken from\n\t\t\t\t   the output of the command to run\n");
-	fprintf(stderr, "\t-\t\t\t-  unused partition entry\n");
+	fprintf(stderr, "\t<t>[/<l>]::<size>[:[+]<offset>]\t-  "
+	    "empty partition of given size and\n\t\t\t\t\t"
+	    "   optional relative or absolute offset\n");
+	fprintf(stderr, "\t<t>[/<l>]:=<file>\t\t-  partition content and size "
+	    "are\n\t\t\t\t\t   determined by the named file\n");
+	fprintf(stderr, "\t<t>[/<l>]:-<cmd>\t\t-  partition content and size "
+	    "are taken\n\t\t\t\t\t   from the output of the command to run\n");
+	fprintf(stderr, "\t-\t\t\t\t-  unused partition entry\n");
 	fprintf(stderr, "\t    where:\n");
 	fprintf(stderr, "\t\t<t>\t-  scheme neutral partition type\n");
 	fprintf(stderr, "\t\t<l>\t-  optional scheme-dependent partition "
@@ -397,12 +399,48 @@ capacity_resize(lba_t end)
 }
 
 static void
+mkimg_validate(void)
+{
+	struct part *part, *part2;
+	lba_t start, end, start2, end2;
+	int i, j;
+
+	i = 0;
+
+	TAILQ_FOREACH(part, &partlist, link) {
+		start = part->block;
+		end = part->block + part->size;
+		j = i + 1;
+		part2 = TAILQ_NEXT(part, link);
+		if (part2 == NULL)
+			break;
+
+		TAILQ_FOREACH_FROM(part2, &partlist, link) {
+			start2 = part2->block;
+			end2 = part2->block + part2->size;
+
+			if ((start >= start2 && start < end2) ||
+			    (end > start2 && end <= end2)) {
+				errx(1, "partition %d overlaps partition %d",
+				    i, j);
+			}
+
+			j++;
+		}
+
+		i++;
+	}
+}
+
+static void
 mkimg(void)
 {
 	FILE *fp;
 	struct part *part;
-	lba_t block;
-	off_t bytesize;
+	lba_t block, blkoffset;
+	off_t bytesize, byteoffset;
+	char *size, *offset;
+	bool abs_offset;
 	int error, fd;
 
 	/* First check partition information */
@@ -413,17 +451,46 @@ mkimg(void)
 	}
 
 	block = scheme_metadata(SCHEME_META_IMG_START, 0);
+	abs_offset = false;
 	TAILQ_FOREACH(part, &partlist, link) {
-		block = scheme_metadata(SCHEME_META_PART_BEFORE, block);
-		if (verbose)
-			fprintf(stderr, "partition %d: starting block %llu "
-			    "... ", part->index + 1, (long long)block);
-		part->block = block;
+		byteoffset = blkoffset = 0;
+		abs_offset = false;
+
+		/* Look for an offset. Set size too if we can. */
 		switch (part->kind) {
 		case PART_KIND_SIZE:
-			if (expand_number(part->contents, &bytesize) == -1)
+			offset = part->contents;
+			size = strsep(&offset, ":");
+			if (expand_number(size, &bytesize) == -1)
 				error = errno;
+			if (offset != NULL) {
+				if (*offset != '+')
+					abs_offset = true;
+				else
+					offset++;
+				if (expand_number(offset, &byteoffset) == -1)
+					error = errno;
+			}
 			break;
+		}
+
+		/* Work out exactly where the partition starts. */
+		blkoffset = (byteoffset + secsz - 1) / secsz;
+		if (abs_offset) {
+			part->block = scheme_metadata(SCHEME_META_PART_ABSOLUTE,
+			    blkoffset);
+		} else {
+			block = scheme_metadata(SCHEME_META_PART_BEFORE,
+			    block + blkoffset);
+			part->block = block;
+		}
+
+		if (verbose)
+			fprintf(stderr, "partition %d: starting block %llu "
+			    "... ", part->index + 1, (long long)part->block);
+
+		/* Pull in partition contents, set size if we haven't yet. */
+		switch (part->kind) {
 		case PART_KIND_FILE:
 			fd = open(part->contents, O_RDONLY, 0);
 			if (fd != -1) {
@@ -449,11 +516,26 @@ mkimg(void)
 			bytesize = part->size * secsz;
 			fprintf(stderr, "size %llu bytes (%llu blocks)\n",
 			     (long long)bytesize, (long long)part->size);
+			if (abs_offset) {
+				fprintf(stderr,
+				    "    location %llu bytes (%llu blocks)\n",
+				    (long long)byteoffset,
+				    (long long)blkoffset);
+			} else if (blkoffset > 0) {
+				fprintf(stderr,
+				    "    offset %llu bytes (%llu blocks)\n",
+				    (long long)byteoffset,
+				    (long long)blkoffset);
+			}
+		}
+		if (!abs_offset) {
+			block = scheme_metadata(SCHEME_META_PART_AFTER,
+			    part->block + part->size);
 		}
-		block = scheme_metadata(SCHEME_META_PART_AFTER,
-		    part->block + part->size);
 	}
 
+	mkimg_validate();
+
 	block = scheme_metadata(SCHEME_META_IMG_END, block);
 	error = image_set_size(block);
 	if (!error) {
diff --git a/usr.bin/mkimg/scheme.h b/usr.bin/mkimg/scheme.h
index 5826036..86b92a3 100644
--- a/usr.bin/mkimg/scheme.h
+++ b/usr.bin/mkimg/scheme.h
@@ -65,10 +65,11 @@ struct mkimg_scheme {
 	const char	*description;
 	struct mkimg_alias *aliases;
 	lba_t		(*metadata)(u_int, lba_t);
-#define	SCHEME_META_IMG_START	1
-#define	SCHEME_META_IMG_END	2
-#define	SCHEME_META_PART_BEFORE	3
-#define	SCHEME_META_PART_AFTER	4
+#define	SCHEME_META_IMG_START		1
+#define	SCHEME_META_IMG_END		2
+#define	SCHEME_META_PART_BEFORE		3
+#define	SCHEME_META_PART_AFTER		4
+#define	SCHEME_META_PART_ABSOLUTE	5
 	int		(*write)(lba_t, void *);
 	u_int		nparts;
 	u_int		labellen;