#ifndef TREE_WALK_H
#define TREE_WALK_H
#include "cache.h"
#define MAX_TRAVERSE_TREES 8
/**
* The tree walking API is used to traverse and inspect trees.
*/
/**
* An entry in a tree. Each entry has a sha1 identifier, pathname, and mode.
*/
struct name_entry {
struct object_id oid;
const char *path;
int pathlen;
unsigned int mode;
};
/**
* A semi-opaque data structure used to maintain the current state of the walk.
*/
struct tree_desc {
/*
* pointer into the memory representation of the tree. It always
* points at the current entry being visited.
*/
const void *buffer;
/* points to the current entry being visited. */
struct name_entry entry;
/* counts the number of bytes left in the `buffer`. */
unsigned int size;
};
/**
* Decode the entry currently being visited (the one pointed to by
* `tree_desc's` `entry` member) and return the sha1 of the entry. The
* `pathp` and `modep` arguments are set to the entry's pathname and mode
* respectively.
*/
static inline const struct object_id *tree_entry_extract(struct tree_desc *desc, const char **pathp, unsigned short *modep)
{
*pathp = desc->entry.path;
*modep = desc->entry.mode;
return &desc->entry.oid;
}
/**
* Calculate the length of a tree entry's pathname. This utilizes the
* memory structure of a tree entry to avoid the overhead of using a
* generic strlen().
*/
static inline int tree_entry_len(const struct name_entry *ne)
{
return ne->pathlen;
}
/*
* The _gently versions of these functions warn and return false on a
* corrupt tree entry rather than dying,
*/
/**
* Walk to the next entry in a tree. This is commonly used in conjunction
* with `tree_entry_extract` to inspect the current entry.
*/
void update_tree_entry(struct tree_desc *);
int update_tree_entry_gently(struct tree_desc *);
/**
* Initialize a `tree_desc` and decode its first entry. The buffer and
* size parameters are assumed to be the same as the buffer and size
* members of `struct tree`.
*/
void init_tree_desc(struct tree_desc *desc, const void *buf, unsigned long size);
int init_tree_desc_gently(struct tree_desc *desc, const void *buf, unsigned long size);
/*
* Visit the next entry in a tree. Returns 1 when there are more entries
* left to visit and 0 when all entries have been visited. This is
* commonly used in the test of a while loop.
*/
int tree_entry(struct tree_desc *, struct name_entry *);
int tree_entry_gently(struct tree_desc *, struct name_entry *);
/**
* Initialize a `tree_desc` and decode its first entry given the
* object ID of a tree. Returns the `buffer` member if the latter
* is a valid tree identifier and NULL otherwise.
*/
void *fill_tree_descriptor(struct repository *r,
struct tree_desc *desc,
const struct object_id *oid);
struct traverse_info;
typedef int (*traverse_callback_t)(int n, unsigned long mask, unsigned long dirmask, struct name_entry *entry, struct traverse_info *);
/**
* Traverse `n` number of trees in parallel. The `fn` callback member of
* `traverse_info` is called once for each tree entry.
*/
int traverse_trees(struct index_state *istate, int n, struct tree_desc *t, struct traverse_info *info);
enum get_oid_result get_tree_entry_follow_symlinks(struct repository *r, struct object_id *tree_oid, const char *name, struct object_id *result, struct strbuf *result_path, unsigned short *mode);
/**
* A structure used to maintain the state of a traversal.
*/
struct traverse_info {
const char *traverse_path;
/*
* points to the traverse_info which was used to descend into the
* current tree. If this is the top-level tree `prev` will point to
* a dummy traverse_info.
*/
struct traverse_info *prev;
/* is the entry for the current tree (if the tree is a subtree). */
const char *name;
size_t namelen;
unsigned mode;
/* is the length of the full path for the current tree. */
size_t pathlen;
struct pathspec *pathspec;
/* can be used by callbacks to maintain directory-file conflicts. */
unsigned long df_conflicts;
/* a callback called for each entry in the tree.
*
* The arguments passed to the traverse callback are as follows:
*
* - `n` counts the number of trees being traversed.
*
* - `mask` has its nth bit set if something exists in the nth entry.
*
* - `dirmask` has its nth bit set if the nth tree's entry is a directory.
*
* - `entry` is an array of size `n` where the nth entry is from the nth tree.
*
* - `info` maintains the state of the traversal.
*
* Returning a negative value will terminate the traversal. Otherwise the
* return value is treated as an update mask. If the nth bit is set the nth tree
* will be updated and if the bit is not set the nth tree entry will be the
* same in the next callback invocation.
*/
traverse_callback_t fn;
/* can be anything the `fn` callback would want to use. */
void *data;
/* tells whether to stop at the first error or not. */
int show_all_errors;
};
/**
* Find an entry in a tree given a pathname and the sha1 of a tree to
* search. Returns 0 if the entry is found and -1 otherwise. The third
* and fourth parameters are set to the entry's sha1 and mode respectively.
*/
int get_tree_entry(struct repository *, const struct object_id *, const char *, struct object_id *, unsigned short *);
/**
* Generate the full pathname of a tree entry based from the root of the
* traversal. For example, if the traversal has recursed into another
* tree named "bar" the pathname of an entry "baz" in the "bar"
* tree would be "bar/baz".
*/
char *make_traverse_path(char *path, size_t pathlen, const struct traverse_info *info,
const char *name, size_t namelen);
/**
* Convenience wrapper to `make_traverse_path` into a strbuf.
*/
void strbuf_make_traverse_path(struct strbuf *out,
const struct traverse_info *info,
const char *name, size_t namelen);
/**
* Initialize a `traverse_info` given the pathname of the tree to start
* traversing from.
*/
void setup_traverse_info(struct traverse_info *info, const char *base);
/**
* Calculate the length of a pathname returned by `make_traverse_path`.
* This utilizes the memory structure of a tree entry to avoid the
* overhead of using a generic strlen().
*/
static inline size_t traverse_path_len(const struct traverse_info *info,
size_t namelen)
{
return st_add(info->pathlen, namelen);
}
/* in general, positive means "kind of interesting" */
enum interesting {
all_entries_not_interesting = -1, /* no, and no subsequent entries will be either */
entry_not_interesting = 0,
entry_interesting = 1,
all_entries_interesting = 2 /* yes, and all subsequent entries will be */
};
enum interesting tree_entry_interesting(struct index_state *istate,
const struct name_entry *,
struct strbuf *, int,
const struct pathspec *ps);
#endif
