From: Thomas Weißschuh <thomas@t-8ch.de>
Date: Tue, 14 Nov 2023 16:53:21 +0000 (+0100)
Subject: libfdisk: add fdisk_partition_get_max_size
X-Git-Tag: v2.40-rc1~157^2~1
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=5ee1a36cdd02dd09aba9a3e40c52efdc04c60f14;p=thirdparty%2Futil-linux.git

libfdisk: add fdisk_partition_get_max_size

Signed-off-by: Thomas Weißschuh <thomas@t-8ch.de>
---

diff --git a/libfdisk/docs/libfdisk-sections.txt b/libfdisk/docs/libfdisk-sections.txt
index 1589413b86..efc138571d 100644
--- a/libfdisk/docs/libfdisk-sections.txt
+++ b/libfdisk/docs/libfdisk-sections.txt
@@ -182,6 +182,7 @@ fdisk_partition_get_size
 fdisk_partition_get_start
 fdisk_partition_get_type
 fdisk_partition_get_uuid
+fdisk_partition_get_max_size
 fdisk_partition_has_end
 fdisk_partition_has_partno
 fdisk_partition_has_size
diff --git a/libfdisk/src/libfdisk.h.in b/libfdisk/src/libfdisk.h.in
index 1c9714975a..9c20f44beb 100644
--- a/libfdisk/src/libfdisk.h.in
+++ b/libfdisk/src/libfdisk.h.in
@@ -540,6 +540,9 @@ extern int fdisk_reorder_partitions(struct fdisk_context *cxt);
 
 extern int fdisk_partition_has_wipe(struct fdisk_context *cxt, struct fdisk_partition *pa);
 
+extern int fdisk_partition_get_max_size(struct fdisk_context *cxt, size_t n,
+					fdisk_sector_t *maxsz);
+
 
 /* table.c */
 extern struct fdisk_table *fdisk_new_table(void);
diff --git a/libfdisk/src/libfdisk.sym b/libfdisk/src/libfdisk.sym
index 71de80589c..bb69e93c41 100644
--- a/libfdisk/src/libfdisk.sym
+++ b/libfdisk/src/libfdisk.sym
@@ -320,3 +320,7 @@ FDISK_2.36 {
 FDISK_2.38 {
 	fdisk_dos_fix_chs;
 } FDISK_2.36;
+
+FDISK_2.40 {
+	fdisk_partition_get_max_size;
+} FDISK_2.38;
diff --git a/libfdisk/src/partition.c b/libfdisk/src/partition.c
index bf3afadb13..1fd3176a6d 100644
--- a/libfdisk/src/partition.c
+++ b/libfdisk/src/partition.c
@@ -1625,3 +1625,55 @@ int fdisk_is_partition_used(struct fdisk_context *cxt, size_t n)
 	return cxt->label->op->part_is_used(cxt, n);
 }
 
+
+/**
+ * fdisk_partition_max_size:
+ * @cxt: context
+ * @n: partition number (0 is the first partition)
+ * @maxsz: returns maximum size of partition
+ *
+ * Find maximum size the partition can be resized to.
+ * Takes into account free space between this partition and the next one.
+ *
+ * Returns: 0 on success, <0 on error.
+ */
+int fdisk_partition_get_max_size(struct fdisk_context *cxt, size_t n,
+				 fdisk_sector_t *maxsz)
+{
+	struct fdisk_partition *cur = NULL;
+	struct fdisk_table *tb = NULL;
+	int rc;
+
+	rc = fdisk_get_partitions(cxt, &tb);
+	if (rc)
+		goto out;
+
+	rc = fdisk_get_freespaces(cxt, &tb);
+	if (rc)
+		goto out;
+
+	rc = fdisk_table_sort_partitions(tb, fdisk_partition_cmp_start);
+	if (rc)
+		goto out;
+
+	cur = fdisk_table_get_partition_by_partno(tb, n);
+	if (!cur)
+		goto einval;
+
+	if (!fdisk_partition_has_start(cur))
+		goto einval;
+
+	if (resize_get_last_possible(tb, cur,
+				     fdisk_partition_get_start(cur), maxsz))
+		goto einval;
+
+out:
+	fdisk_unref_partition(cur);
+	fdisk_unref_table(tb);
+
+	return rc;
+
+einval:
+	rc = -EINVAL;
+	goto out;
+}