#ifndef TREE_WALK_H
#define TREE_WALK_H

struct name_entry {
        const unsigned char *sha1;
        const char *path;
        unsigned int mode;
};

struct tree_desc {
        const void *buffer;
        struct name_entry entry;
        unsigned int size;
};

static inline const unsigned char *tree_entry_extract(struct tree_desc *desc, const char **pathp, unsigned int *modep)
{
        *pathp = desc->entry.path;
        *modep = canon_mode(desc->entry.mode);
        return desc->entry.sha1;
}

static inline int tree_entry_len(const char *name, const unsigned char *sha1)
{
        return (const char *)sha1 - name - 1;
}

void update_tree_entry(struct tree_desc *);
void init_tree_desc(struct tree_desc *desc, const void *buf, unsigned long size);

/* Helper function that does both of the above and returns true for success */
int tree_entry(struct tree_desc *, struct name_entry *);

void *fill_tree_descriptor(struct tree_desc *desc, const unsigned char *sha1);

struct traverse_info;
typedef void (*traverse_callback_t)(int n, unsigned long mask, struct name_entry *entry, struct traverse_info *);
void traverse_trees(int n, struct tree_desc *t, struct traverse_info *info);

struct traverse_info {
        struct traverse_info *prev;
        struct name_entry name;
        int pathlen;

        traverse_callback_t fn;
        void *data;
};

int get_tree_entry(const unsigned char *, const char *, unsigned char *, unsigned *);
extern char *make_traverse_path(char *path, const struct traverse_info *info, const struct name_entry *n);
extern void setup_traverse_info(struct traverse_info *info, const char *base);

static inline int traverse_path_len(const struct traverse_info *info, const struct name_entry *n)
{
        return info->pathlen + tree_entry_len(n->path, n->sha1);
}

#endif