5 files changed, 55 insertions, 4 deletions
diff --git a/lib/sqfs/Makemodule.am b/lib/sqfs/Makemodule.am
index c687d1c..be405cf 100644
--- a/lib/sqfs/Makemodule.am
+++ b/lib/sqfs/Makemodule.am
@@ -23,6 +23,7 @@ libsquashfs_la_SOURCES += lib/sqfs/write_super.c lib/sqfs/data_writer/block.c
 libsquashfs_la_SOURCES += lib/sqfs/data_writer/internal.h lib/sqfs/data_reader.c
 libsquashfs_la_SOURCES += lib/sqfs/data_writer/common.c
 libsquashfs_la_SOURCES += lib/sqfs/data_writer/fileapi.c
+libsquashfs_la_SOURCES += lib/sqfs/str_table.c lib/sqfs/str_table.h
 libsquashfs_la_CPPFLAGS = $(AM_CPPFLAGS)
 libsquashfs_la_LDFLAGS = $(AM_LDFLAGS)
 libsquashfs_la_CFLAGS = $(AM_CFLAGS) $(PTHREAD_CFLAGS) $(ZLIB_CFLAGS)
diff --git a/lib/util/str_table.c b/lib/sqfs/str_table.c
index 513b243..1ec0ef7 100644
--- a/lib/util/str_table.c
+++ b/lib/sqfs/str_table.c
@@ -11,8 +11,8 @@
 #include <string.h>
 
 #include "sqfs/error.h"
-#include "util/str_table.h"
 #include "util/util.h"
+#include "str_table.h"
 
 /* R5 hash function (borrowed from reiserfs) */
 static sqfs_u32 strhash(const char *s)
diff --git a/lib/sqfs/str_table.h b/lib/sqfs/str_table.h
new file mode 100644
index 0000000..61f8aa5
--- /dev/null
+++ b/lib/sqfs/str_table.h
@@ -0,0 +1,51 @@
+/* SPDX-License-Identifier: LGPL-3.0-or-later */
+/*
+ * str_table.h
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#ifndef STR_TABLE_H
+#define STR_TABLE_H
+
+#include "sqfs/predef.h"
+
+typedef struct str_bucket_t {
+	struct str_bucket_t *next;
+	char *str;
+	size_t index;
+	size_t refcount;
+} str_bucket_t;
+
+/* Stores strings in a hash table and assigns an incremental, unique ID to
+   each string. Subsequent additions return the existing ID. The ID can be
+   used for (hopefully) constant time lookup of the original string. */
+typedef struct {
+	str_bucket_t **buckets;
+	size_t num_buckets;
+
+	char **strings;
+	size_t num_strings;
+	size_t max_strings;
+} str_table_t;
+
+/* `size` is the number of hash table buckets to use internally. */
+SQFS_INTERNAL int str_table_init(str_table_t *table, size_t size);
+
+SQFS_INTERNAL void str_table_cleanup(str_table_t *table);
+
+/* Resolve a string to an incremental, unique ID. */
+SQFS_INTERNAL
+int str_table_get_index(str_table_t *table, const char *str, size_t *idx);
+
+/* Resolve a unique ID to the string it represents.
+   Returns NULL if the ID is unknown, i.e. out of bounds. */
+SQFS_INTERNAL
+const char *str_table_get_string(str_table_t *table, size_t index);
+
+SQFS_INTERNAL void str_table_add_ref(str_table_t *table, size_t index);
+
+SQFS_INTERNAL void str_table_del_ref(str_table_t *table, size_t index);
+
+SQFS_INTERNAL size_t str_table_get_ref_count(str_table_t *table, size_t index);
+
+#endif /* STR_TABLE_H */
diff --git a/lib/sqfs/xattr_writer.c b/lib/sqfs/xattr_writer.c
index 81ee26c..2e6a074 100644
--- a/lib/sqfs/xattr_writer.c
+++ b/lib/sqfs/xattr_writer.c
@@ -15,8 +15,8 @@
 #include "sqfs/block.h"
 #include "sqfs/io.h"
 
-#include "util/str_table.h"
 #include "util/util.h"
+#include "str_table.h"
 
 #include <stdlib.h>
 #include <string.h>
diff --git a/lib/util/Makemodule.am b/lib/util/Makemodule.am
index 07e94e2..426e088 100644
--- a/lib/util/Makemodule.am
+++ b/lib/util/Makemodule.am
@@ -1,5 +1,4 @@
-libutil_la_SOURCES = include/util/util.h include/util/str_table.h
-libutil_la_SOURCES += lib/util/str_table.c lib/util/alloc.c
+libutil_la_SOURCES = include/util/util.h lib/util/alloc.c
 libutil_la_CFLAGS = $(AM_CFLAGS)
 libutil_la_CPPFLAGS = $(AM_CPPFLAGS)
 libutil_la_LDFLAGS = $(AM_LDFLAGS)