libfdisk: add table sort function, use it in get_freespace

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/libfdisk/src/libfdisk.h b/libfdisk/src/libfdisk.h
index d3f51c812d53da32aa36d684b49330275133f527..af31b6b8c185ac3950be87ca320b21ef825690ed 100644 (file)
--- a/libfdisk/src/libfdisk.h
+++ b/libfdisk/src/libfdisk.h
@@ -182,14 +182,22 @@ extern void fdisk_reset_partition(struct fdisk_partition *pa);
 extern void fdisk_ref_partition(struct fdisk_partition *pa);
 extern void fdisk_unref_partition(struct fdisk_partition *pa);
 extern int fdisk_partition_is_freespace(struct fdisk_partition *pa);
+
 extern int fdisk_partition_set_start(struct fdisk_partition *pa, uint64_t off);
 extern uint64_t fdisk_partition_get_start(struct fdisk_partition *pa);
+extern int fdisk_partition_cmp_start(struct fdisk_partition *a,
+                             struct fdisk_partition *b);
+
 extern int fdisk_partition_set_end(struct fdisk_partition *pa, uint64_t off, int isrel);
 extern uint64_t fdisk_partition_get_end(struct fdisk_partition *pa);
 extern int fdisk_partition_set_size(struct fdisk_partition *pa, uint64_t size);
 extern uint64_t fdisk_partition_get_size(struct fdisk_partition *pa);
+
 extern int fdisk_partition_set_partno(struct fdisk_partition *pa, size_t n);
 extern size_t fdisk_partition_get_partno(struct fdisk_partition *pa);
+extern int fdisk_partition_cmp_partno(struct fdisk_partition *a,
+                             struct fdisk_partition *b);
+
 extern int fdisk_partition_set_type(struct fdisk_partition *pa, struct fdisk_parttype *type);
 extern const struct fdisk_parttype *fdisk_partition_get_type(struct fdisk_partition *pa);
 extern int fdisk_partition_set_name(struct fdisk_partition *pa, const char *name);
@@ -225,6 +233,10 @@ extern int fdisk_table_remove_partition(struct fdisk_table *tb, struct fdisk_par
 extern int fdisk_get_partitions(struct fdisk_context *cxt, struct fdisk_table **tb);
 extern int fdisk_get_freespaces(struct fdisk_context *cxt, struct fdisk_table **tb);
 
+extern int fdisk_table_sort_partitions(struct fdisk_table *tb,
+                       int (*cmp)(struct fdisk_partition *,
+                                  struct fdisk_partition *));
+
 extern int fdisk_table_to_string(struct fdisk_table *tb,
                          struct fdisk_context *cxt,
                          int *cols, size_t ncols,  char **data);

diff --git a/libfdisk/src/partition.c b/libfdisk/src/partition.c
index 65a284e75da79c3ce3c31a82ee6380c0497d5207..da5e75c258bae770a08d260ed2a7692f6d6b394f 100644 (file)
--- a/libfdisk/src/partition.c
+++ b/libfdisk/src/partition.c
@@ -66,6 +66,12 @@ uint64_t fdisk_partition_get_start(struct fdisk_partition *pa)
        return pa ? pa->start : 0;
 }
 
+int fdisk_partition_cmp_start(struct fdisk_partition *a,
+                             struct fdisk_partition *b)
+{
+       return a->start - b->start;
+}
+
 int fdisk_partition_set_end(struct fdisk_partition *pa, uint64_t off, int isrel)
 {
        if (!pa)
@@ -109,6 +115,12 @@ size_t fdisk_partition_get_partno(struct fdisk_partition *pa)
        return pa ? pa->partno : (size_t) -1;
 }
 
+int fdisk_partition_cmp_partno(struct fdisk_partition *a,
+                              struct fdisk_partition *b)
+{
+       return a->partno - b->partno;
+}
+
 int fdisk_partition_set_type(struct fdisk_partition *pa, struct fdisk_parttype *type)
 {
        if (!pa)

diff --git a/libfdisk/src/table.c b/libfdisk/src/table.c
index af056da188fdcc69942675f219e73cca02e00b5f..84ce357dd11a1a1333525f29699109fd9b008c7b 100644 (file)
--- a/libfdisk/src/table.c
+++ b/libfdisk/src/table.c
@@ -287,6 +287,29 @@ int fdisk_get_partitions(struct fdisk_context *cxt, struct fdisk_table **tb)
        return 0;
 }
 
+typedef        int (*fdisk_partcmp_t)(struct fdisk_partition *, struct fdisk_partition *);
+
+static int cmp_parts_wrapper(struct list_head *a, struct list_head *b, void *data)
+{
+       struct fdisk_partition *pa = list_entry(a, struct fdisk_partition, parts),
+                              *pb = list_entry(b, struct fdisk_partition, parts);
+
+       fdisk_partcmp_t cmp = (fdisk_partcmp_t) data;
+
+       return cmp(pa, pb);
+}
+
+int fdisk_table_sort_partitions(struct fdisk_table *tb,
+                       int (*cmp)(struct fdisk_partition *,
+                                  struct fdisk_partition *))
+{
+       if (!tb)
+               return -EINVAL;
+
+       list_sort(&tb->parts, cmp_parts_wrapper, (void *) cmp);
+       return 0;
+}
+
 int fdisk_table_add_freespace(
                        struct fdisk_context *cxt,
                        struct fdisk_table *tb,
@@ -294,11 +317,15 @@ int fdisk_table_add_freespace(
                        uint64_t end,
                        int dosort)
 {
-       struct fdisk_partition *pa = fdisk_new_partition();
+       struct fdisk_partition *pa;
        int rc = 0;
 
        assert(tb);
 
+       if (start == end)
+               return 0;
+
+       pa = fdisk_new_partition();
        if (!pa)
                return -ENOMEM;
        pa->freespace = 1;
@@ -337,8 +364,10 @@ int fdisk_table_add_freespace(
 int fdisk_get_freespaces(struct fdisk_context *cxt, struct fdisk_table **tb)
 {
        int dosort, rc = 0;
-       size_t i;
        uint64_t last, grain;
+       struct fdisk_table *parts = NULL;
+       struct fdisk_partition *pa;
+       struct fdisk_iter itr;
 
        DBG(LABEL, dbgprint("get freespace"));
 
@@ -351,31 +380,33 @@ int fdisk_get_freespaces(struct fdisk_context *cxt, struct fdisk_table **tb)
        if (cxt->label->op->get_freespace)
                return cxt->label->op->get_freespace(cxt, *tb);
 
-       /* generic way -- check for gaps betten partitions */
+       /* generic way */
+       rc = fdisk_get_partitions(cxt, &parts);
+       if (rc)
+               goto done;
+
+       fdisk_table_sort_partitions(parts, fdisk_partition_cmp_start);
+       fdisk_reset_iter(&itr, FDISK_ITER_FORWARD);
+
        dosort = !fdisk_table_is_empty(*tb);
        last = cxt->first_lba;
        grain = cxt->grain / cxt->sector_size;
 
-       for (i = 0; rc == 0 && i < cxt->label->nparts_max; i++) {
-               struct fdisk_partition *pa = NULL;
+       /* analyze gaps between partitions */
+       while (fdisk_table_next_partition(parts, &itr, &pa) == 0) {
 
-               if (fdisk_get_partition(cxt, i, &pa))
-                       continue;
-               if (!fdisk_partition_is_used(pa)) {
-                       fdisk_unref_partition(pa);
-                       continue;
-               }
+               DBG(LABEL, dbgprint("freespace analyze: partno=%zu, start=%ju, end=%ju",
+                                       pa->partno, pa->start, pa->end));
 
-               /* add free-space (before partition) to the list */
+               if (!fdisk_partition_is_used(pa))
+                       continue;
                if (last + grain < pa->start) {
                        rc = fdisk_table_add_freespace(cxt, *tb,
                                last + (last > cxt->first_lba ? 1 : 0),
                                pa->start - 1,
                                dosort);
                }
-
                last = pa->end;
-               fdisk_unref_partition(pa);
        }
 
        /* add free-space (behind last partition) to the list */
@@ -384,6 +415,8 @@ int fdisk_get_freespaces(struct fdisk_context *cxt, struct fdisk_table **tb)
                        last + (last > cxt->first_lba ? 1 : 0),
                        cxt->last_lba,
                        dosort);
+done:
+       fdisk_unref_table(parts);
        return rc;
 }