directory: replace DirectoryList with dirvec

Small memory reduction compared to songvec since most users have
much fewer dirs than songs, but still nice to have.

1 files changed, 73 insertions, 0 deletions

diff --git a/src/dirvec.h b/src/dirvec.h
new file mode 100644
index 000000000..8b2f634e2
--- /dev/null
+++ b/src/dirvec.h
@@ -0,0 +1,73 @@
+#ifndef DIRVEC_H
+#define DIRVEC_H
+
+#include "directory.h"
+#include "os_compat.h"
+#include "utils.h"
+
+static size_t dv_size(struct dirvec *dv)
+{
+	return dv->nr * sizeof(Directory *);
+}
+
+/* Only used for sorting/searching a dirvec, not general purpose compares */
+static int dirvec_cmp(const void *d1, const void *d2)
+{
+	const Directory *a = ((const Directory * const *)d1)[0];
+	const Directory *b = ((const Directory * const *)d2)[0];
+	return strcmp(a->path, b->path);
+}
+
+static void dirvec_sort(struct dirvec *dv)
+{
+	qsort(dv->base, dv->nr, sizeof(Directory *), dirvec_cmp);
+}
+
+static Directory *dirvec_find(struct dirvec *dv, const char *path)
+{
+	int i;
+
+	for (i = dv->nr; --i >= 0; )
+		if (!strcmp(dv->base[i]->path, path))
+			return dv->base[i];
+	return NULL;
+}
+
+static int dirvec_delete(struct dirvec *dv, Directory *del)
+{
+	int i;
+
+	for (i = dv->nr; --i >= 0; ) {
+		if (dv->base[i] != del)
+			continue;
+		/* we _don't_ call freeDirectory() here */
+		if (!--dv->nr) {
+			free(dv->base);
+			dv->base = NULL;
+		} else {
+			memmove(&dv->base[i], &dv->base[i + 1],
+				(dv->nr - i + 1) * sizeof(Directory *));
+			dv->base = xrealloc(dv->base, dv_size(dv));
+		}
+		return i;
+	}
+
+	return -1; /* not found */
+}
+
+static void dirvec_add(struct dirvec *dv, Directory *add)
+{
+	++dv->nr;
+	dv->base = xrealloc(dv->base, dv_size(dv));
+	dv->base[dv->nr - 1] = add;
+}
+
+static void dirvec_destroy(struct dirvec *dv)
+{
+	if (dv->base) {
+		free(dv->base);
+		dv->base = NULL;
+	}
+	dv->nr = 0;
+}
+#endif /* DIRVEC_H */