com32/chain: partiter - more precise comments / output

Signed-off-by: Michal Soltys <soltys@ziu.info>

2 files changed, 23 insertions, 19 deletions

diff --git a/com32/chain/partiter.c b/com32/chain/partiter.c
index 25810ebf..2f6197a2 100644
--- a/com32/chain/partiter.c
+++ b/com32/chain/partiter.c
@@ -179,7 +179,7 @@ static int notsane_logical(const struct part_iter *iter)
 	!sane(dp[0].start_lba, dp[0].length) ||
 	end_log > iter->dos.ebr_size) {
 
-	error("Insane logical partition.\n");
+	error("Logical partition (in EBR) with invalid offset and/or length.\n");
 	return -1;
     }
 
@@ -204,7 +204,7 @@ static int notsane_extended(const struct part_iter *iter)
 	return 0;
 
     if (!ost_is_nondata(dp[1].ostype)) {
-	error("2nd EBR entry must be extended or empty.\n");
+	error("The 2nd EBR entry must be extended or empty.\n");
 	return -1;
     }
 
@@ -215,7 +215,7 @@ static int notsane_extended(const struct part_iter *iter)
 	!sane(dp[1].start_lba, dp[1].length) ||
 	end_ebr > iter->dos.bebr_size) {
 
-	error("Insane extended partition.\n");
+	error("Extended partition (EBR) with invalid offset and/or length.\n");
 	return -1;
     }
 
@@ -239,7 +239,7 @@ static int notsane_primary(const struct part_iter *iter)
 	!dp->length ||
 	!sane(dp->start_lba, dp->length) ||
 	dp->start_lba + dp->length > iter->di.lbacnt) {
-	error("Primary (MBR) with invalid offset and/or length.\n");
+	error("Primary partition (in MBR) with invalid offset and/or length.\n");
 	return -1;
     }
 
@@ -279,7 +279,7 @@ static int dos_next_mbr(struct part_iter *iter, uint32_t *lba,
 
 	if (ost_is_ext(dp->ostype)) {
 	    if (iter->dos.bebr_index0 >= 0) {
-		error("You have more than 1 extended partition.\n");
+		error("More than 1 extended partition.\n");
 		iter->status = PI_INSANE;
 		return -1;
 	    }
@@ -454,8 +454,9 @@ static int pi_dos_next(struct part_iter *iter)
 	return iter->status;
 
     /*
-     * note special index handling, if we have PIF_STEPALL set - this is made
-     * to keep index consistent with non-PIF_STEPALL iterators
+     * note special index handling:
+     * in case PIF_STEPALL is set - this makes the index consistent with
+     * non-PIF_STEPALL iterators
      */
 
     if (iter->index0 >= 4 && !dos_part->ostype)
@@ -607,7 +608,7 @@ struct part_iter *pi_begin(const struct disk_info *di, int flags)
 	}
 	/* Check array checksum(s). */
 	if (!valid_crc(gpth->table_chksum, (const uint8_t *)gptl, (unsigned int)gpt_lsiz)) {
-	    error("Main GPT partition list's checksum invalid, trying backup.\n");
+	    error("Checksum of the main GPT partition list is invalid, trying backup.\n");
 	    free(gptl);
 	    /* secondary array directly precedes secondary header */
 	    if (!(gptl = disk_read_sectors(di, gpth->lba_alt - gpt_lcnt, gpt_lcnt))) {
@@ -615,7 +616,7 @@ struct part_iter *pi_begin(const struct disk_info *di, int flags)
 		goto bail;
 	    }
 	    if (!valid_crc(gpth->table_chksum, (const uint8_t *)gptl, gpt_lsiz)) {
-		error("Backup GPT partition list's checksum invalid.\n");
+		error("Checksum of the backup GPT partition list is invalid, giving up.\n");
 		goto bail;
 	    }
 	}
diff --git a/com32/chain/partiter.h b/com32/chain/partiter.h
index 10f18824..18c33153 100644
--- a/com32/chain/partiter.h
+++ b/com32/chain/partiter.h
@@ -71,16 +71,19 @@ struct part_iter {
     struct disk_info di;
     union {
 	struct {
-	    uint32_t disk_sig;
-	    uint32_t nebr_lba;
-	    uint32_t cebr_lba;
-	    /* internal */
-	    uint32_t ebr_start;
-	    uint32_t ebr_size;
-	    uint32_t bebr_start;
-	    uint32_t bebr_size;
-	    int bebr_index0;
-	    int skipcnt;
+	    uint32_t disk_sig;    /* 32bit disk signature as stored in MBR */
+
+	    uint32_t bebr_start;  /* abs lba of base extended partition */
+	    uint32_t bebr_size;   /* size of base extended partition */
+
+	    uint32_t cebr_lba;    /* absolute lba of curr ext. partition */
+	    uint32_t nebr_lba;    /* absolute lba of next ext. partition */
+
+	    uint32_t ebr_start;   /* relative (to bebr) lba of next extended partition */
+	    uint32_t ebr_size;    /* size of next extended partition */
+
+	    int bebr_index0;      /* index of (0-3) of base ext. part., -1 if not present in MBR */
+	    int skipcnt;          /* how many logical holes were skipped */
 	} dos;
 	struct {
 	    struct guid disk_guid;