From 4dbdc42d9e7c3968ff7f690d00680419c9b8cb0f Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Tue, 9 Apr 2024 15:34:27 +0200 Subject: Adding upstream version 1:2.43.0. Signed-off-by: Daniel Baumann --- tree-walk.h | 228 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 228 insertions(+) create mode 100644 tree-walk.h (limited to 'tree-walk.h') diff --git a/tree-walk.h b/tree-walk.h new file mode 100644 index 0000000..a6bfa3d --- /dev/null +++ b/tree-walk.h @@ -0,0 +1,228 @@ +#ifndef TREE_WALK_H +#define TREE_WALK_H + +#include "hash-ll.h" + +struct index_state; +struct repository; + +/** + * 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; + + /* option flags passed via init_tree_desc_gently() */ + enum tree_desc_flags { + TREE_DESC_RAW_MODES = (1 << 0), + } flags; +}; + +/** + * 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, + enum tree_desc_flags flags); + +/* + * 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 *, + const struct pathspec *ps); + +#endif -- cgit v1.2.3