1 files changed, 117 insertions, 0 deletions
diff --git a/lib/idcache.c b/lib/idcache.c
new file mode 100644
index 0000000..5550223
--- /dev/null
+++ b/lib/idcache.c
@@ -0,0 +1,117 @@
+/*
+ * No copyright is claimed.  This code is in the public domain; do with
+ * it what you wish.
+ *
+ * Written by Karel Zak <kzak@redhat.com>
+ */
+#include <wchar.h>
+#include <pwd.h>
+#include <grp.h>
+#include <sys/types.h>
+
+#include "c.h"
+#include "idcache.h"
+
+struct identry *get_id(struct idcache *ic, unsigned long int id)
+{
+	struct identry *ent;
+
+	if (!ic)
+		return NULL;
+
+	for (ent = ic->ent; ent; ent = ent->next) {
+		if (ent->id == id)
+			return ent;
+	}
+
+	return NULL;
+}
+
+struct idcache *new_idcache(void)
+{
+	return calloc(1, sizeof(struct idcache));
+}
+
+void free_idcache(struct idcache *ic)
+{
+	struct identry *ent = ic->ent;
+
+	while (ent) {
+		struct identry *next = ent->next;
+		free(ent->name);
+		free(ent);
+		ent = next;
+	}
+
+	free(ic);
+}
+
+static void add_id(struct idcache *ic, char *name, unsigned long int id)
+{
+	struct identry *ent, *x;
+	int w = 0;
+
+	ent = calloc(1, sizeof(struct identry));
+	if (!ent)
+		return;
+	ent->id = id;
+
+	if (name) {
+#ifdef HAVE_WIDECHAR
+		wchar_t wc[LOGIN_NAME_MAX + 1];
+
+		if (mbstowcs(wc, name, LOGIN_NAME_MAX) > 0) {
+			wc[LOGIN_NAME_MAX] = '\0';
+			w = wcswidth(wc, LOGIN_NAME_MAX);
+		}
+		else
+#endif
+			w = strlen(name);
+	}
+
+	/* note, we ignore names with non-printable widechars */
+	if (w > 0) {
+		ent->name = strdup(name);
+		if (!ent->name) {
+			free(ent);
+			return;
+		}
+	} else {
+		if (asprintf(&ent->name, "%lu", id) < 0) {
+			free(ent);
+			return;
+		}
+	}
+
+	for (x = ic->ent; x && x->next; x = x->next);
+
+	if (x)
+		x->next = ent;
+	else
+		ic->ent = ent;
+
+	if (w <= 0)
+		w = ent->name ? strlen(ent->name) : 0;
+	ic->width = ic->width < w ? w : ic->width;
+}
+
+void add_uid(struct idcache *cache, unsigned long int id)
+{
+	struct identry *ent= get_id(cache, id);
+
+	if (!ent) {
+		struct passwd *pw = getpwuid((uid_t) id);
+		add_id(cache, pw ? pw->pw_name : NULL, id);
+	}
+}
+
+void add_gid(struct idcache *cache, unsigned long int id)
+{
+	struct identry *ent = get_id(cache, id);
+
+	if (!ent) {
+		struct group *gr = getgrgid((gid_t) id);
+		add_id(cache, gr ? gr->gr_name : NULL, id);
+	}
+}
+