libsmartcols: add scols_sort_table()

 * add pointer to column cmp() function [scols_column_set_cmpfunc()]

 * allow to store per-cell application private data
   (to make it possible to sort tables on data independent on cell
    output data) [scols_cell_set_userdata() ...]

 * make it possible to access line cell by column
   [scols_line_get_column_cell()]

Sort and cmp() stuff based on patches from Shakur Shams Mullick.

Co-Author: Shakur Shams Mullick <shakursmullick@gmail.com>
Signed-off-by: Shakur Shams Mullick <shakursmullick@gmail.com>
Signed-off-by: Karel Zak <kzak@redhat.com>

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

1 files changed, 39 insertions, 0 deletions

diff --git a/libsmartcols/src/table.c b/libsmartcols/src/table.c
index d4c61eea3..a51a84abc 100644
--- a/libsmartcols/src/table.c
+++ b/libsmartcols/src/table.c
@@ -977,3 +977,42 @@ char *scols_table_get_line_separator(struct libscols_table *tb)
 	return tb->linesep;
 
 }
+
+static int cells_cmp_wrapper(struct list_head *a, struct list_head *b, void *data)
+{
+	struct libscols_column *cl = (struct libscols_column *) data;
+	struct libscols_line *ra, *rb;
+	struct libscols_cell *ca, *cb;
+
+	assert(a);
+	assert(b);
+	assert(cl);
+
+	ra = list_entry(a, struct libscols_line, ln_lines);
+	rb = list_entry(b, struct libscols_line, ln_lines);
+	ca = scols_line_get_cell(ra, cl->seqnum);
+	cb = scols_line_get_cell(rb, cl->seqnum);
+
+	return cl->cmpfunc(ca, cb, cl->cmpfunc_data);
+}
+
+/**
+ * scols_sort_table:
+ * @tb: table
+ * @cl: order by this column
+ *
+ * Orders the table by the column. See also scols_column_set_cmpfunc().
+ *
+ * Returns: 0, a negative value in case of an error.
+ */
+int scols_sort_table(struct libscols_table *tb, struct libscols_column *cl)
+{
+	assert(tb);
+	assert(cl);
+
+	if (!tb || !cl)
+		return -EINVAL;
+
+	list_sort(&tb->tb_lines, cells_cmp_wrapper, cl);
+	return 0;
+}