Merge branch 'mh/ref-iterators'

The API to iterate over all the refs (i.e. for_each_ref(), etc.)
has been revamped.

* mh/ref-iterators:
  for_each_reflog(): reimplement using iterators
  dir_iterator: new API for iterating over a directory tree
  for_each_reflog(): don't abort for bad references
  do_for_each_ref(): reimplement using reference iteration
  refs: introduce an iterator interface
  ref_resolves_to_object(): new function
  entry_resolves_to_object(): rename function from ref_resolves_to_object()
  get_ref_cache(): only create an instance if there is a submodule
  remote rm: handle symbolic refs correctly
  delete_refs(): add a flags argument
  refs: use name "prefix" consistently
  do_for_each_ref(): move docstring to the header file
  refs: remove unnecessary "extern" keywords
This commit is contained in:
Junio C Hamano 2016-07-25 14:13:33 -07:00
commit 87492cb24d
11 changed files with 1458 additions and 322 deletions

View File

@ -718,6 +718,7 @@ LIB_OBJS += diff-lib.o
LIB_OBJS += diff-no-index.o
LIB_OBJS += diff.o
LIB_OBJS += dir.o
LIB_OBJS += dir-iterator.o
LIB_OBJS += editor.o
LIB_OBJS += entry.o
LIB_OBJS += environment.o
@ -782,6 +783,7 @@ LIB_OBJS += read-cache.o
LIB_OBJS += reflog-walk.o
LIB_OBJS += refs.o
LIB_OBJS += refs/files-backend.o
LIB_OBJS += refs/iterator.o
LIB_OBJS += ref-filter.o
LIB_OBJS += remote.o
LIB_OBJS += replace_object.o

View File

@ -921,7 +921,7 @@ static int prune_refs(struct refspec *refs, int ref_count, struct ref *ref_map,
for (ref = stale_refs; ref; ref = ref->next)
string_list_append(&refnames, ref->name);
result = delete_refs(&refnames);
result = delete_refs(&refnames, 0);
string_list_clear(&refnames, 0);
}

View File

@ -539,10 +539,6 @@ static int add_branch_for_removal(const char *refname,
return 0;
}
/* make sure that symrefs are deleted */
if (flags & REF_ISSYMREF)
return unlink(git_path("%s", refname));
string_list_append(branches->branches, refname);
return 0;
@ -788,7 +784,7 @@ static int rm(int argc, const char **argv)
strbuf_release(&buf);
if (!result)
result = delete_refs(&branches);
result = delete_refs(&branches, REF_NODEREF);
string_list_clear(&branches, 0);
if (skipped.nr) {
@ -1304,7 +1300,7 @@ static int prune_remote(const char *remote, int dry_run)
string_list_sort(&refs_to_prune);
if (!dry_run)
result |= delete_refs(&refs_to_prune);
result |= delete_refs(&refs_to_prune, 0);
for_each_string_list_item(item, &states.stale) {
const char *refname = item->util;

202
dir-iterator.c Normal file
View File

@ -0,0 +1,202 @@
#include "cache.h"
#include "dir.h"
#include "iterator.h"
#include "dir-iterator.h"
struct dir_iterator_level {
int initialized;
DIR *dir;
/*
* The length of the directory part of path at this level
* (including a trailing '/'):
*/
size_t prefix_len;
/*
* The last action that has been taken with the current entry
* (needed for directories, which have to be included in the
* iteration and also iterated into):
*/
enum {
DIR_STATE_ITER,
DIR_STATE_RECURSE
} dir_state;
};
/*
* The full data structure used to manage the internal directory
* iteration state. It includes members that are not part of the
* public interface.
*/
struct dir_iterator_int {
struct dir_iterator base;
/*
* The number of levels currently on the stack. This is always
* at least 1, because when it becomes zero the iteration is
* ended and this struct is freed.
*/
size_t levels_nr;
/* The number of levels that have been allocated on the stack */
size_t levels_alloc;
/*
* A stack of levels. levels[0] is the uppermost directory
* that will be included in this iteration.
*/
struct dir_iterator_level *levels;
};
int dir_iterator_advance(struct dir_iterator *dir_iterator)
{
struct dir_iterator_int *iter =
(struct dir_iterator_int *)dir_iterator;
while (1) {
struct dir_iterator_level *level =
&iter->levels[iter->levels_nr - 1];
struct dirent *de;
if (!level->initialized) {
/*
* Note: dir_iterator_begin() ensures that
* path is not the empty string.
*/
if (!is_dir_sep(iter->base.path.buf[iter->base.path.len - 1]))
strbuf_addch(&iter->base.path, '/');
level->prefix_len = iter->base.path.len;
level->dir = opendir(iter->base.path.buf);
if (!level->dir && errno != ENOENT) {
warning("error opening directory %s: %s",
iter->base.path.buf, strerror(errno));
/* Popping the level is handled below */
}
level->initialized = 1;
} else if (S_ISDIR(iter->base.st.st_mode)) {
if (level->dir_state == DIR_STATE_ITER) {
/*
* The directory was just iterated
* over; now prepare to iterate into
* it.
*/
level->dir_state = DIR_STATE_RECURSE;
ALLOC_GROW(iter->levels, iter->levels_nr + 1,
iter->levels_alloc);
level = &iter->levels[iter->levels_nr++];
level->initialized = 0;
continue;
} else {
/*
* The directory has already been
* iterated over and iterated into;
* we're done with it.
*/
}
}
if (!level->dir) {
/*
* This level is exhausted (or wasn't opened
* successfully); pop up a level.
*/
if (--iter->levels_nr == 0)
return dir_iterator_abort(dir_iterator);
continue;
}
/*
* Loop until we find an entry that we can give back
* to the caller:
*/
while (1) {
strbuf_setlen(&iter->base.path, level->prefix_len);
errno = 0;
de = readdir(level->dir);
if (!de) {
/* This level is exhausted; pop up a level. */
if (errno) {
warning("error reading directory %s: %s",
iter->base.path.buf, strerror(errno));
} else if (closedir(level->dir))
warning("error closing directory %s: %s",
iter->base.path.buf, strerror(errno));
level->dir = NULL;
if (--iter->levels_nr == 0)
return dir_iterator_abort(dir_iterator);
break;
}
if (is_dot_or_dotdot(de->d_name))
continue;
strbuf_addstr(&iter->base.path, de->d_name);
if (lstat(iter->base.path.buf, &iter->base.st) < 0) {
if (errno != ENOENT)
warning("error reading path '%s': %s",
iter->base.path.buf,
strerror(errno));
continue;
}
/*
* We have to set these each time because
* the path strbuf might have been realloc()ed.
*/
iter->base.relative_path =
iter->base.path.buf + iter->levels[0].prefix_len;
iter->base.basename =
iter->base.path.buf + level->prefix_len;
level->dir_state = DIR_STATE_ITER;
return ITER_OK;
}
}
}
int dir_iterator_abort(struct dir_iterator *dir_iterator)
{
struct dir_iterator_int *iter = (struct dir_iterator_int *)dir_iterator;
for (; iter->levels_nr; iter->levels_nr--) {
struct dir_iterator_level *level =
&iter->levels[iter->levels_nr - 1];
if (level->dir && closedir(level->dir)) {
strbuf_setlen(&iter->base.path, level->prefix_len);
warning("error closing directory %s: %s",
iter->base.path.buf, strerror(errno));
}
}
free(iter->levels);
strbuf_release(&iter->base.path);
free(iter);
return ITER_DONE;
}
struct dir_iterator *dir_iterator_begin(const char *path)
{
struct dir_iterator_int *iter = xcalloc(1, sizeof(*iter));
struct dir_iterator *dir_iterator = &iter->base;
if (!path || !*path)
die("BUG: empty path passed to dir_iterator_begin()");
strbuf_init(&iter->base.path, PATH_MAX);
strbuf_addstr(&iter->base.path, path);
ALLOC_GROW(iter->levels, 10, iter->levels_alloc);
iter->levels_nr = 1;
iter->levels[0].initialized = 0;
return dir_iterator;
}

87
dir-iterator.h Normal file
View File

@ -0,0 +1,87 @@
#ifndef DIR_ITERATOR_H
#define DIR_ITERATOR_H
/*
* Iterate over a directory tree.
*
* Iterate over a directory tree, recursively, including paths of all
* types and hidden paths. Skip "." and ".." entries and don't follow
* symlinks except for the original path.
*
* Every time dir_iterator_advance() is called, update the members of
* the dir_iterator structure to reflect the next path in the
* iteration. The order that paths are iterated over within a
* directory is undefined, but directory paths are always iterated
* over before the subdirectory contents.
*
* A typical iteration looks like this:
*
* int ok;
* struct iterator *iter = dir_iterator_begin(path);
*
* while ((ok = dir_iterator_advance(iter)) == ITER_OK) {
* if (want_to_stop_iteration()) {
* ok = dir_iterator_abort(iter);
* break;
* }
*
* // Access information about the current path:
* if (S_ISDIR(iter->st.st_mode))
* printf("%s is a directory\n", iter->relative_path);
* }
*
* if (ok != ITER_DONE)
* handle_error();
*
* Callers are allowed to modify iter->path while they are working,
* but they must restore it to its original contents before calling
* dir_iterator_advance() again.
*/
struct dir_iterator {
/* The current path: */
struct strbuf path;
/*
* The current path relative to the starting path. This part
* of the path always uses "/" characters to separate path
* components:
*/
const char *relative_path;
/* The current basename: */
const char *basename;
/* The result of calling lstat() on path: */
struct stat st;
};
/*
* Start a directory iteration over path. Return a dir_iterator that
* holds the internal state of the iteration.
*
* The iteration includes all paths under path, not including path
* itself and not including "." or ".." entries.
*
* path is the starting directory. An internal copy will be made.
*/
struct dir_iterator *dir_iterator_begin(const char *path);
/*
* Advance the iterator to the first or next item and return ITER_OK.
* If the iteration is exhausted, free the dir_iterator and any
* resources associated with it and return ITER_DONE. On error, free
* dir_iterator and associated resources and return ITER_ERROR. It is
* a bug to use iterator or call this function again after it has
* returned ITER_DONE or ITER_ERROR.
*/
int dir_iterator_advance(struct dir_iterator *iterator);
/*
* End the iteration before it has been exhausted. Free the
* dir_iterator and any associated resources and return ITER_DONE. On
* error, free the dir_iterator and return ITER_ERROR.
*/
int dir_iterator_abort(struct dir_iterator *iterator);
#endif

81
iterator.h Normal file
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@ -0,0 +1,81 @@
#ifndef ITERATOR_H
#define ITERATOR_H
/*
* Generic constants related to iterators.
*/
/*
* The attempt to advance the iterator was successful; the iterator
* reflects the new current entry.
*/
#define ITER_OK 0
/*
* The iterator is exhausted and has been freed.
*/
#define ITER_DONE -1
/*
* The iterator experienced an error. The iteration has been aborted
* and the iterator has been freed.
*/
#define ITER_ERROR -2
/*
* Return values for selector functions for merge iterators. The
* numerical values of these constants are important and must be
* compatible with ITER_DONE and ITER_ERROR.
*/
enum iterator_selection {
/* End the iteration without an error: */
ITER_SELECT_DONE = ITER_DONE,
/* Report an error and abort the iteration: */
ITER_SELECT_ERROR = ITER_ERROR,
/*
* The next group of constants are masks that are useful
* mainly internally.
*/
/* The LSB selects whether iter0/iter1 is the "current" iterator: */
ITER_CURRENT_SELECTION_MASK = 0x01,
/* iter0 is the "current" iterator this round: */
ITER_CURRENT_SELECTION_0 = 0x00,
/* iter1 is the "current" iterator this round: */
ITER_CURRENT_SELECTION_1 = 0x01,
/* Yield the value from the current iterator? */
ITER_YIELD_CURRENT = 0x02,
/* Discard the value from the secondary iterator? */
ITER_SKIP_SECONDARY = 0x04,
/*
* The constants that a selector function should usually
* return.
*/
/* Yield the value from iter0: */
ITER_SELECT_0 = ITER_CURRENT_SELECTION_0 | ITER_YIELD_CURRENT,
/* Yield the value from iter0 and discard the one from iter1: */
ITER_SELECT_0_SKIP_1 = ITER_SELECT_0 | ITER_SKIP_SECONDARY,
/* Discard the value from iter0 without yielding anything this round: */
ITER_SKIP_0 = ITER_CURRENT_SELECTION_1 | ITER_SKIP_SECONDARY,
/* Yield the value from iter1: */
ITER_SELECT_1 = ITER_CURRENT_SELECTION_1 | ITER_YIELD_CURRENT,
/* Yield the value from iter1 and discard the one from iter0: */
ITER_SELECT_1_SKIP_0 = ITER_SELECT_1 | ITER_SKIP_SECONDARY,
/* Discard the value from iter1 without yielding anything this round: */
ITER_SKIP_1 = ITER_CURRENT_SELECTION_0 | ITER_SKIP_SECONDARY
};
#endif /* ITERATOR_H */

20
refs.c
View File

@ -1120,6 +1120,26 @@ int head_ref(each_ref_fn fn, void *cb_data)
return head_ref_submodule(NULL, fn, cb_data);
}
/*
* Call fn for each reference in the specified submodule for which the
* refname begins with prefix. If trim is non-zero, then trim that
* many characters off the beginning of each refname before passing
* the refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to
* include broken references in the iteration. If fn ever returns a
* non-zero value, stop the iteration and return that value;
* otherwise, return 0.
*/
static int do_for_each_ref(const char *submodule, const char *prefix,
each_ref_fn fn, int trim, int flags, void *cb_data)
{
struct ref_iterator *iter;
iter = files_ref_iterator_begin(submodule, prefix, flags);
iter = prefix_ref_iterator_begin(iter, prefix, trim);
return do_for_each_ref_iterator(iter, fn, cb_data);
}
int for_each_ref(each_ref_fn fn, void *cb_data)
{
return do_for_each_ref(NULL, "", fn, 0, 0, cb_data);

115
refs.h
View File

@ -52,19 +52,19 @@
#define RESOLVE_REF_NO_RECURSE 0x02
#define RESOLVE_REF_ALLOW_BAD_NAME 0x04
extern const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
const char *resolve_ref_unsafe(const char *refname, int resolve_flags,
unsigned char *sha1, int *flags);
extern char *resolve_refdup(const char *refname, int resolve_flags,
char *resolve_refdup(const char *refname, int resolve_flags,
unsigned char *sha1, int *flags);
extern int read_ref_full(const char *refname, int resolve_flags,
int read_ref_full(const char *refname, int resolve_flags,
unsigned char *sha1, int *flags);
extern int read_ref(const char *refname, unsigned char *sha1);
int read_ref(const char *refname, unsigned char *sha1);
extern int ref_exists(const char *refname);
int ref_exists(const char *refname);
extern int is_branch(const char *refname);
int is_branch(const char *refname);
/*
* If refname is a non-symbolic reference that refers to a tag object,
@ -74,24 +74,25 @@ extern int is_branch(const char *refname);
* Symbolic references are considered unpeelable, even if they
* ultimately resolve to a peelable tag.
*/
extern int peel_ref(const char *refname, unsigned char *sha1);
int peel_ref(const char *refname, unsigned char *sha1);
/**
* Resolve refname in the nested "gitlink" repository that is located
* at path. If the resolution is successful, return 0 and set sha1 to
* the name of the object; otherwise, return a non-zero value.
*/
extern int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sha1);
int resolve_gitlink_ref(const char *path, const char *refname,
unsigned char *sha1);
/*
* Return true iff abbrev_name is a possible abbreviation for
* full_name according to the rules defined by ref_rev_parse_rules in
* refs.c.
*/
extern int refname_match(const char *abbrev_name, const char *full_name);
int refname_match(const char *abbrev_name, const char *full_name);
extern int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref);
extern int dwim_log(const char *str, int len, unsigned char *sha1, char **ref);
int dwim_ref(const char *str, int len, unsigned char *sha1, char **ref);
int dwim_log(const char *str, int len, unsigned char *sha1, char **ref);
/*
* A ref_transaction represents a collection of ref updates
@ -140,7 +141,9 @@ extern int dwim_log(const char *str, int len, unsigned char *sha1, char **ref);
struct ref_transaction;
/*
* Bit values set in the flags argument passed to each_ref_fn():
* Bit values set in the flags argument passed to each_ref_fn() and
* stored in ref_iterator::flags. Other bits are for internal use
* only:
*/
/* Reference is a symbolic reference. */
@ -182,38 +185,45 @@ typedef int each_ref_fn(const char *refname,
* modifies the reference also returns a nonzero value to immediately
* stop the iteration.
*/
extern int head_ref(each_ref_fn fn, void *cb_data);
extern int for_each_ref(each_ref_fn fn, void *cb_data);
extern int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data);
extern int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data, unsigned int broken);
extern int for_each_tag_ref(each_ref_fn fn, void *cb_data);
extern int for_each_branch_ref(each_ref_fn fn, void *cb_data);
extern int for_each_remote_ref(each_ref_fn fn, void *cb_data);
extern int for_each_replace_ref(each_ref_fn fn, void *cb_data);
extern int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data);
extern int for_each_glob_ref_in(each_ref_fn fn, const char *pattern, const char *prefix, void *cb_data);
int head_ref(each_ref_fn fn, void *cb_data);
int for_each_ref(each_ref_fn fn, void *cb_data);
int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data);
int for_each_fullref_in(const char *prefix, each_ref_fn fn, void *cb_data,
unsigned int broken);
int for_each_tag_ref(each_ref_fn fn, void *cb_data);
int for_each_branch_ref(each_ref_fn fn, void *cb_data);
int for_each_remote_ref(each_ref_fn fn, void *cb_data);
int for_each_replace_ref(each_ref_fn fn, void *cb_data);
int for_each_glob_ref(each_ref_fn fn, const char *pattern, void *cb_data);
int for_each_glob_ref_in(each_ref_fn fn, const char *pattern,
const char *prefix, void *cb_data);
extern int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
extern int for_each_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
extern int for_each_ref_in_submodule(const char *submodule, const char *prefix,
int head_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
int for_each_ref_submodule(const char *submodule,
each_ref_fn fn, void *cb_data);
int for_each_ref_in_submodule(const char *submodule, const char *prefix,
each_ref_fn fn, void *cb_data);
int for_each_tag_ref_submodule(const char *submodule,
each_ref_fn fn, void *cb_data);
int for_each_branch_ref_submodule(const char *submodule,
each_ref_fn fn, void *cb_data);
int for_each_remote_ref_submodule(const char *submodule,
each_ref_fn fn, void *cb_data);
extern int for_each_tag_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
extern int for_each_branch_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
extern int for_each_remote_ref_submodule(const char *submodule, each_ref_fn fn, void *cb_data);
extern int head_ref_namespaced(each_ref_fn fn, void *cb_data);
extern int for_each_namespaced_ref(each_ref_fn fn, void *cb_data);
int head_ref_namespaced(each_ref_fn fn, void *cb_data);
int for_each_namespaced_ref(each_ref_fn fn, void *cb_data);
/* can be used to learn about broken ref and symref */
extern int for_each_rawref(each_ref_fn fn, void *cb_data);
int for_each_rawref(each_ref_fn fn, void *cb_data);
static inline const char *has_glob_specials(const char *pattern)
{
return strpbrk(pattern, "?*[");
}
extern void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname);
extern void warn_dangling_symrefs(FILE *fp, const char *msg_fmt, const struct string_list *refnames);
void warn_dangling_symref(FILE *fp, const char *msg_fmt, const char *refname);
void warn_dangling_symrefs(FILE *fp, const char *msg_fmt,
const struct string_list *refnames);
/*
* Flags for controlling behaviour of pack_refs()
@ -245,13 +255,13 @@ int pack_refs(unsigned int flags);
int safe_create_reflog(const char *refname, int force_create, struct strbuf *err);
/** Reads log for the value of ref during at_time. **/
extern int read_ref_at(const char *refname, unsigned int flags,
int read_ref_at(const char *refname, unsigned int flags,
unsigned long at_time, int cnt,
unsigned char *sha1, char **msg,
unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt);
/** Check if a particular reflog exists */
extern int reflog_exists(const char *refname);
int reflog_exists(const char *refname);
/*
* Delete the specified reference. If old_sha1 is non-NULL, then
@ -260,21 +270,26 @@ extern int reflog_exists(const char *refname);
* exists, regardless of its old value. It is an error for old_sha1 to
* be NULL_SHA1. flags is passed through to ref_transaction_delete().
*/
extern int delete_ref(const char *refname, const unsigned char *old_sha1,
int delete_ref(const char *refname, const unsigned char *old_sha1,
unsigned int flags);
/*
* Delete the specified references. If there are any problems, emit
* errors but attempt to keep going (i.e., the deletes are not done in
* an all-or-nothing transaction).
* an all-or-nothing transaction). flags is passed through to
* ref_transaction_delete().
*/
extern int delete_refs(struct string_list *refnames);
int delete_refs(struct string_list *refnames, unsigned int flags);
/** Delete a reflog */
extern int delete_reflog(const char *refname);
int delete_reflog(const char *refname);
/* iterate over reflog entries */
typedef int each_reflog_ent_fn(unsigned char *osha1, unsigned char *nsha1, const char *, unsigned long, int, const char *, void *);
typedef int each_reflog_ent_fn(
unsigned char *old_sha1, unsigned char *new_sha1,
const char *committer, unsigned long timestamp,
int tz, const char *msg, void *cb_data);
int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_data);
int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void *cb_data);
@ -282,7 +297,7 @@ int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void
* Calls the specified function for each reflog file until it returns nonzero,
* and returns the value
*/
extern int for_each_reflog(each_ref_fn, void *);
int for_each_reflog(each_ref_fn fn, void *cb_data);
#define REFNAME_ALLOW_ONELEVEL 1
#define REFNAME_REFSPEC_PATTERN 2
@ -295,16 +310,16 @@ extern int for_each_reflog(each_ref_fn, void *);
* allow a single "*" wildcard character in the refspec. No leading or
* repeated slashes are accepted.
*/
extern int check_refname_format(const char *refname, int flags);
int check_refname_format(const char *refname, int flags);
extern const char *prettify_refname(const char *refname);
const char *prettify_refname(const char *refname);
extern char *shorten_unambiguous_ref(const char *refname, int strict);
char *shorten_unambiguous_ref(const char *refname, int strict);
/** rename ref, return 0 on success **/
extern int rename_ref(const char *oldref, const char *newref, const char *logmsg);
int rename_ref(const char *oldref, const char *newref, const char *logmsg);
extern int create_symref(const char *refname, const char *target, const char *logmsg);
int create_symref(const char *refname, const char *target, const char *logmsg);
/*
* Update HEAD of the specified gitdir.
@ -313,7 +328,7 @@ extern int create_symref(const char *refname, const char *target, const char *lo
* $GIT_DIR points to.
* Return 0 if successful, non-zero otherwise.
* */
extern int set_worktree_head_symref(const char *gitdir, const char *target);
int set_worktree_head_symref(const char *gitdir, const char *target);
enum action_on_err {
UPDATE_REFS_MSG_ON_ERR,
@ -463,7 +478,7 @@ int update_ref(const char *msg, const char *refname,
const unsigned char *new_sha1, const unsigned char *old_sha1,
unsigned int flags, enum action_on_err onerr);
extern int parse_hide_refs_config(const char *var, const char *value, const char *);
int parse_hide_refs_config(const char *var, const char *value, const char *);
/*
* Check whether a ref is hidden. If no namespace is set, both the first and
@ -473,7 +488,7 @@ extern int parse_hide_refs_config(const char *var, const char *value, const char
* the ref is outside that namespace, the first parameter is NULL. The second
* parameter always points to the full ref name.
*/
extern int ref_is_hidden(const char *, const char *);
int ref_is_hidden(const char *, const char *);
enum ref_type {
REF_TYPE_PER_WORKTREE,
@ -522,7 +537,7 @@ typedef void reflog_expiry_cleanup_fn(void *cb_data);
* enum expire_reflog_flags. The three function pointers are described
* above. On success, return zero.
*/
extern int reflog_expire(const char *refname, const unsigned char *sha1,
int reflog_expire(const char *refname, const unsigned char *sha1,
unsigned int flags,
reflog_expiry_prepare_fn prepare_fn,
reflog_expiry_should_prune_fn should_prune_fn,

View File

@ -1,6 +1,8 @@
#include "../cache.h"
#include "../refs.h"
#include "refs-internal.h"
#include "../iterator.h"
#include "../dir-iterator.h"
#include "../lockfile.h"
#include "../object.h"
#include "../dir.h"
@ -513,68 +515,36 @@ static void sort_ref_dir(struct ref_dir *dir)
}
/*
* Return true iff the reference described by entry can be resolved to
* an object in the database. Emit a warning if the referred-to
* object does not exist.
* Return true if refname, which has the specified oid and flags, can
* be resolved to an object in the database. If the referred-to object
* does not exist, emit a warning and return false.
*/
static int ref_resolves_to_object(struct ref_entry *entry)
static int ref_resolves_to_object(const char *refname,
const struct object_id *oid,
unsigned int flags)
{
if (entry->flag & REF_ISBROKEN)
if (flags & REF_ISBROKEN)
return 0;
if (!has_sha1_file(entry->u.value.oid.hash)) {
error("%s does not point to a valid object!", entry->name);
if (!has_sha1_file(oid->hash)) {
error("%s does not point to a valid object!", refname);
return 0;
}
return 1;
}
/*
* current_ref is a performance hack: when iterating over references
* using the for_each_ref*() functions, current_ref is set to the
* current reference's entry before calling the callback function. If
* the callback function calls peel_ref(), then peel_ref() first
* checks whether the reference to be peeled is the current reference
* (it usually is) and if so, returns that reference's peeled version
* if it is available. This avoids a refname lookup in a common case.
* Return true if the reference described by entry can be resolved to
* an object in the database; otherwise, emit a warning and return
* false.
*/
static struct ref_entry *current_ref;
static int entry_resolves_to_object(struct ref_entry *entry)
{
return ref_resolves_to_object(entry->name,
&entry->u.value.oid, entry->flag);
}
typedef int each_ref_entry_fn(struct ref_entry *entry, void *cb_data);
struct ref_entry_cb {
const char *base;
int trim;
int flags;
each_ref_fn *fn;
void *cb_data;
};
/*
* Handle one reference in a do_for_each_ref*()-style iteration,
* calling an each_ref_fn for each entry.
*/
static int do_one_ref(struct ref_entry *entry, void *cb_data)
{
struct ref_entry_cb *data = cb_data;
struct ref_entry *old_current_ref;
int retval;
if (!starts_with(entry->name, data->base))
return 0;
if (!(data->flags & DO_FOR_EACH_INCLUDE_BROKEN) &&
!ref_resolves_to_object(entry))
return 0;
/* Store the old value, in case this is a recursive call: */
old_current_ref = current_ref;
current_ref = entry;
retval = data->fn(entry->name + data->trim, &entry->u.value.oid,
entry->flag, data->cb_data);
current_ref = old_current_ref;
return retval;
}
/*
* Call fn for each reference in dir that has index in the range
* offset <= index < dir->nr. Recurse into subdirectories that are in
@ -603,78 +573,6 @@ static int do_for_each_entry_in_dir(struct ref_dir *dir, int offset,
return 0;
}
/*
* Call fn for each reference in the union of dir1 and dir2, in order
* by refname. Recurse into subdirectories. If a value entry appears
* in both dir1 and dir2, then only process the version that is in
* dir2. The input dirs must already be sorted, but subdirs will be
* sorted as needed. fn is called for all references, including
* broken ones.
*/
static int do_for_each_entry_in_dirs(struct ref_dir *dir1,
struct ref_dir *dir2,
each_ref_entry_fn fn, void *cb_data)
{
int retval;
int i1 = 0, i2 = 0;
assert(dir1->sorted == dir1->nr);
assert(dir2->sorted == dir2->nr);
while (1) {
struct ref_entry *e1, *e2;
int cmp;
if (i1 == dir1->nr) {
return do_for_each_entry_in_dir(dir2, i2, fn, cb_data);
}
if (i2 == dir2->nr) {
return do_for_each_entry_in_dir(dir1, i1, fn, cb_data);
}
e1 = dir1->entries[i1];
e2 = dir2->entries[i2];
cmp = strcmp(e1->name, e2->name);
if (cmp == 0) {
if ((e1->flag & REF_DIR) && (e2->flag & REF_DIR)) {
/* Both are directories; descend them in parallel. */
struct ref_dir *subdir1 = get_ref_dir(e1);
struct ref_dir *subdir2 = get_ref_dir(e2);
sort_ref_dir(subdir1);
sort_ref_dir(subdir2);
retval = do_for_each_entry_in_dirs(
subdir1, subdir2, fn, cb_data);
i1++;
i2++;
} else if (!(e1->flag & REF_DIR) && !(e2->flag & REF_DIR)) {
/* Both are references; ignore the one from dir1. */
retval = fn(e2, cb_data);
i1++;
i2++;
} else {
die("conflict between reference and directory: %s",
e1->name);
}
} else {
struct ref_entry *e;
if (cmp < 0) {
e = e1;
i1++;
} else {
e = e2;
i2++;
}
if (e->flag & REF_DIR) {
struct ref_dir *subdir = get_ref_dir(e);
sort_ref_dir(subdir);
retval = do_for_each_entry_in_dir(
subdir, 0, fn, cb_data);
} else {
retval = fn(e, cb_data);
}
}
if (retval)
return retval;
}
}
/*
* Load all of the refs from the dir into our in-memory cache. The hard work
* of loading loose refs is done by get_ref_dir(), so we just need to recurse
@ -691,6 +589,153 @@ static void prime_ref_dir(struct ref_dir *dir)
}
}
/*
* A level in the reference hierarchy that is currently being iterated
* through.
*/
struct cache_ref_iterator_level {
/*
* The ref_dir being iterated over at this level. The ref_dir
* is sorted before being stored here.
*/
struct ref_dir *dir;
/*
* The index of the current entry within dir (which might
* itself be a directory). If index == -1, then the iteration
* hasn't yet begun. If index == dir->nr, then the iteration
* through this level is over.
*/
int index;
};
/*
* Represent an iteration through a ref_dir in the memory cache. The
* iteration recurses through subdirectories.
*/
struct cache_ref_iterator {
struct ref_iterator base;
/*
* The number of levels currently on the stack. This is always
* at least 1, because when it becomes zero the iteration is
* ended and this struct is freed.
*/
size_t levels_nr;
/* The number of levels that have been allocated on the stack */
size_t levels_alloc;
/*
* A stack of levels. levels[0] is the uppermost level that is
* being iterated over in this iteration. (This is not
* necessary the top level in the references hierarchy. If we
* are iterating through a subtree, then levels[0] will hold
* the ref_dir for that subtree, and subsequent levels will go
* on from there.)
*/
struct cache_ref_iterator_level *levels;
};
static int cache_ref_iterator_advance(struct ref_iterator *ref_iterator)
{
struct cache_ref_iterator *iter =
(struct cache_ref_iterator *)ref_iterator;
while (1) {
struct cache_ref_iterator_level *level =
&iter->levels[iter->levels_nr - 1];
struct ref_dir *dir = level->dir;
struct ref_entry *entry;
if (level->index == -1)
sort_ref_dir(dir);
if (++level->index == level->dir->nr) {
/* This level is exhausted; pop up a level */
if (--iter->levels_nr == 0)
return ref_iterator_abort(ref_iterator);
continue;
}
entry = dir->entries[level->index];
if (entry->flag & REF_DIR) {
/* push down a level */
ALLOC_GROW(iter->levels, iter->levels_nr + 1,
iter->levels_alloc);
level = &iter->levels[iter->levels_nr++];
level->dir = get_ref_dir(entry);
level->index = -1;
} else {
iter->base.refname = entry->name;
iter->base.oid = &entry->u.value.oid;
iter->base.flags = entry->flag;
return ITER_OK;
}
}
}
static enum peel_status peel_entry(struct ref_entry *entry, int repeel);
static int cache_ref_iterator_peel(struct ref_iterator *ref_iterator,
struct object_id *peeled)
{
struct cache_ref_iterator *iter =
(struct cache_ref_iterator *)ref_iterator;
struct cache_ref_iterator_level *level;
struct ref_entry *entry;
level = &iter->levels[iter->levels_nr - 1];
if (level->index == -1)
die("BUG: peel called before advance for cache iterator");
entry = level->dir->entries[level->index];
if (peel_entry(entry, 0))
return -1;
hashcpy(peeled->hash, entry->u.value.peeled.hash);
return 0;
}
static int cache_ref_iterator_abort(struct ref_iterator *ref_iterator)
{
struct cache_ref_iterator *iter =
(struct cache_ref_iterator *)ref_iterator;
free(iter->levels);
base_ref_iterator_free(ref_iterator);
return ITER_DONE;
}
static struct ref_iterator_vtable cache_ref_iterator_vtable = {
cache_ref_iterator_advance,
cache_ref_iterator_peel,
cache_ref_iterator_abort
};
static struct ref_iterator *cache_ref_iterator_begin(struct ref_dir *dir)
{
struct cache_ref_iterator *iter;
struct ref_iterator *ref_iterator;
struct cache_ref_iterator_level *level;
iter = xcalloc(1, sizeof(*iter));
ref_iterator = &iter->base;
base_ref_iterator_init(ref_iterator, &cache_ref_iterator_vtable);
ALLOC_GROW(iter->levels, 10, iter->levels_alloc);
iter->levels_nr = 1;
level = &iter->levels[0];
level->index = -1;
level->dir = dir;
return ref_iterator;
}
struct nonmatching_ref_data {
const struct string_list *skip;
const char *conflicting_refname;
@ -954,15 +999,26 @@ static struct ref_cache *lookup_ref_cache(const char *submodule)
/*
* Return a pointer to a ref_cache for the specified submodule. For
* the main repository, use submodule==NULL. The returned structure
* will be allocated and initialized but not necessarily populated; it
* should not be freed.
* the main repository, use submodule==NULL; such a call cannot fail.
* For a submodule, the submodule must exist and be a nonbare
* repository, otherwise return NULL.
*
* The returned structure will be allocated and initialized but not
* necessarily populated; it should not be freed.
*/
static struct ref_cache *get_ref_cache(const char *submodule)
{
struct ref_cache *refs = lookup_ref_cache(submodule);
if (!refs)
if (!refs) {
struct strbuf submodule_sb = STRBUF_INIT;
strbuf_addstr(&submodule_sb, submodule);
if (is_nonbare_repository_dir(&submodule_sb))
refs = create_ref_cache(submodule);
strbuf_release(&submodule_sb);
}
return refs;
}
@ -1341,14 +1397,11 @@ int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *sh
return -1;
strbuf_add(&submodule, path, len);
refs = lookup_ref_cache(submodule.buf);
refs = get_ref_cache(submodule.buf);
if (!refs) {
if (!is_nonbare_repository_dir(&submodule)) {
strbuf_release(&submodule);
return -1;
}
refs = create_ref_cache(submodule.buf);
}
strbuf_release(&submodule);
retval = resolve_gitlink_ref_recursive(refs, refname, sha1, 0);
@ -1790,11 +1843,12 @@ int peel_ref(const char *refname, unsigned char *sha1)
int flag;
unsigned char base[20];
if (current_ref && (current_ref->name == refname
|| !strcmp(current_ref->name, refname))) {
if (peel_entry(current_ref, 0))
if (current_ref_iter && current_ref_iter->refname == refname) {
struct object_id peeled;
if (ref_iterator_peel(current_ref_iter, &peeled))
return -1;
hashcpy(sha1, current_ref->u.value.peeled.hash);
hashcpy(sha1, peeled.hash);
return 0;
}
@ -1822,90 +1876,137 @@ int peel_ref(const char *refname, unsigned char *sha1)
return peel_object(base, sha1);
}
/*
* Call fn for each reference in the specified ref_cache, omitting
* references not in the containing_dir of base. fn is called for all
* references, including broken ones. If fn ever returns a non-zero
* value, stop the iteration and return that value; otherwise, return
* 0.
*/
static int do_for_each_entry(struct ref_cache *refs, const char *base,
each_ref_entry_fn fn, void *cb_data)
{
struct files_ref_iterator {
struct ref_iterator base;
struct packed_ref_cache *packed_ref_cache;
struct ref_dir *loose_dir;
struct ref_dir *packed_dir;
int retval = 0;
struct ref_iterator *iter0;
unsigned int flags;
};
/*
* We must make sure that all loose refs are read before accessing the
* packed-refs file; this avoids a race condition in which loose refs
* are migrated to the packed-refs file by a simultaneous process, but
* our in-memory view is from before the migration. get_packed_ref_cache()
* takes care of making sure our view is up to date with what is on
* disk.
*/
loose_dir = get_loose_refs(refs);
if (base && *base) {
loose_dir = find_containing_dir(loose_dir, base, 0);
}
if (loose_dir)
prime_ref_dir(loose_dir);
packed_ref_cache = get_packed_ref_cache(refs);
acquire_packed_ref_cache(packed_ref_cache);
packed_dir = get_packed_ref_dir(packed_ref_cache);
if (base && *base) {
packed_dir = find_containing_dir(packed_dir, base, 0);
}
if (packed_dir && loose_dir) {
sort_ref_dir(packed_dir);
sort_ref_dir(loose_dir);
retval = do_for_each_entry_in_dirs(
packed_dir, loose_dir, fn, cb_data);
} else if (packed_dir) {
sort_ref_dir(packed_dir);
retval = do_for_each_entry_in_dir(
packed_dir, 0, fn, cb_data);
} else if (loose_dir) {
sort_ref_dir(loose_dir);
retval = do_for_each_entry_in_dir(
loose_dir, 0, fn, cb_data);
}
release_packed_ref_cache(packed_ref_cache);
return retval;
}
/*
* Call fn for each reference in the specified ref_cache for which the
* refname begins with base. If trim is non-zero, then trim that many
* characters off the beginning of each refname before passing the
* refname to fn. flags can be DO_FOR_EACH_INCLUDE_BROKEN to include
* broken references in the iteration. If fn ever returns a non-zero
* value, stop the iteration and return that value; otherwise, return
* 0.
*/
int do_for_each_ref(const char *submodule, const char *base,
each_ref_fn fn, int trim, int flags, void *cb_data)
static int files_ref_iterator_advance(struct ref_iterator *ref_iterator)
{
struct ref_entry_cb data;
struct ref_cache *refs;
struct files_ref_iterator *iter =
(struct files_ref_iterator *)ref_iterator;
int ok;
refs = get_ref_cache(submodule);
data.base = base;
data.trim = trim;
data.flags = flags;
data.fn = fn;
data.cb_data = cb_data;
while ((ok = ref_iterator_advance(iter->iter0)) == ITER_OK) {
if (!(iter->flags & DO_FOR_EACH_INCLUDE_BROKEN) &&
!ref_resolves_to_object(iter->iter0->refname,
iter->iter0->oid,
iter->iter0->flags))
continue;
iter->base.refname = iter->iter0->refname;
iter->base.oid = iter->iter0->oid;
iter->base.flags = iter->iter0->flags;
return ITER_OK;
}
iter->iter0 = NULL;
if (ref_iterator_abort(ref_iterator) != ITER_DONE)
ok = ITER_ERROR;
return ok;
}
static int files_ref_iterator_peel(struct ref_iterator *ref_iterator,
struct object_id *peeled)
{
struct files_ref_iterator *iter =
(struct files_ref_iterator *)ref_iterator;
return ref_iterator_peel(iter->iter0, peeled);
}
static int files_ref_iterator_abort(struct ref_iterator *ref_iterator)
{
struct files_ref_iterator *iter =
(struct files_ref_iterator *)ref_iterator;
int ok = ITER_DONE;
if (iter->iter0)
ok = ref_iterator_abort(iter->iter0);
release_packed_ref_cache(iter->packed_ref_cache);
base_ref_iterator_free(ref_iterator);
return ok;
}
static struct ref_iterator_vtable files_ref_iterator_vtable = {
files_ref_iterator_advance,
files_ref_iterator_peel,
files_ref_iterator_abort
};
struct ref_iterator *files_ref_iterator_begin(
const char *submodule,
const char *prefix, unsigned int flags)
{
struct ref_cache *refs = get_ref_cache(submodule);
struct ref_dir *loose_dir, *packed_dir;
struct ref_iterator *loose_iter, *packed_iter;
struct files_ref_iterator *iter;
struct ref_iterator *ref_iterator;
if (!refs)
return empty_ref_iterator_begin();
if (ref_paranoia < 0)
ref_paranoia = git_env_bool("GIT_REF_PARANOIA", 0);
if (ref_paranoia)
data.flags |= DO_FOR_EACH_INCLUDE_BROKEN;
flags |= DO_FOR_EACH_INCLUDE_BROKEN;
return do_for_each_entry(refs, base, do_one_ref, &data);
iter = xcalloc(1, sizeof(*iter));
ref_iterator = &iter->base;
base_ref_iterator_init(ref_iterator, &files_ref_iterator_vtable);
/*
* We must make sure that all loose refs are read before
* accessing the packed-refs file; this avoids a race
* condition if loose refs are migrated to the packed-refs
* file by a simultaneous process, but our in-memory view is
* from before the migration. We ensure this as follows:
* First, we call prime_ref_dir(), which pre-reads the loose
* references for the subtree into the cache. (If they've
* already been read, that's OK; we only need to guarantee
* that they're read before the packed refs, not *how much*
* before.) After that, we call get_packed_ref_cache(), which
* internally checks whether the packed-ref cache is up to
* date with what is on disk, and re-reads it if not.
*/
loose_dir = get_loose_refs(refs);
if (prefix && *prefix)
loose_dir = find_containing_dir(loose_dir, prefix, 0);
if (loose_dir) {
prime_ref_dir(loose_dir);
loose_iter = cache_ref_iterator_begin(loose_dir);
} else {
/* There's nothing to iterate over. */
loose_iter = empty_ref_iterator_begin();
}
iter->packed_ref_cache = get_packed_ref_cache(refs);
acquire_packed_ref_cache(iter->packed_ref_cache);
packed_dir = get_packed_ref_dir(iter->packed_ref_cache);
if (prefix && *prefix)
packed_dir = find_containing_dir(packed_dir, prefix, 0);
if (packed_dir) {
packed_iter = cache_ref_iterator_begin(packed_dir);
} else {
/* There's nothing to iterate over. */
packed_iter = empty_ref_iterator_begin();
}
iter->iter0 = overlay_ref_iterator_begin(loose_iter, packed_iter);
iter->flags = flags;
return ref_iterator;
}
/*
@ -2226,7 +2327,7 @@ static int pack_if_possible_fn(struct ref_entry *entry, void *cb_data)
return 0;
/* Do not pack symbolic or broken refs: */
if ((entry->flag & REF_ISSYMREF) || !ref_resolves_to_object(entry))
if ((entry->flag & REF_ISSYMREF) || !entry_resolves_to_object(entry))
return 0;
/* Add a packed ref cache entry equivalent to the loose entry. */
@ -2412,7 +2513,7 @@ static int delete_ref_loose(struct ref_lock *lock, int flag, struct strbuf *err)
return 0;
}
int delete_refs(struct string_list *refnames)
int delete_refs(struct string_list *refnames, unsigned int flags)
{
struct strbuf err = STRBUF_INIT;
int i, result = 0;
@ -2441,7 +2542,7 @@ int delete_refs(struct string_list *refnames)
for (i = 0; i < refnames->nr; i++) {
const char *refname = refnames->items[i].string;
if (delete_ref(refname, NULL, 0))
if (delete_ref(refname, NULL, flags))
result |= error(_("could not remove reference %s"), refname);
}
@ -3191,60 +3292,88 @@ int for_each_reflog_ent(const char *refname, each_reflog_ent_fn fn, void *cb_dat
strbuf_release(&sb);
return ret;
}
/*
* Call fn for each reflog in the namespace indicated by name. name
* must be empty or end with '/'. Name will be used as a scratch
* space, but its contents will be restored before return.
*/
static int do_for_each_reflog(struct strbuf *name, each_ref_fn fn, void *cb_data)
{
DIR *d = opendir(git_path("logs/%s", name->buf));
int retval = 0;
struct dirent *de;
int oldlen = name->len;
if (!d)
return name->len ? errno : 0;
struct files_reflog_iterator {
struct ref_iterator base;
while ((de = readdir(d)) != NULL) {
struct stat st;
if (de->d_name[0] == '.')
continue;
if (ends_with(de->d_name, ".lock"))
continue;
strbuf_addstr(name, de->d_name);
if (stat(git_path("logs/%s", name->buf), &st) < 0) {
; /* silently ignore */
} else {
if (S_ISDIR(st.st_mode)) {
strbuf_addch(name, '/');
retval = do_for_each_reflog(name, fn, cb_data);
} else {
struct dir_iterator *dir_iterator;
struct object_id oid;
};
if (read_ref_full(name->buf, 0, oid.hash, NULL))
retval = error("bad ref for %s", name->buf);
else
retval = fn(name->buf, &oid, 0, cb_data);
static int files_reflog_iterator_advance(struct ref_iterator *ref_iterator)
{
struct files_reflog_iterator *iter =
(struct files_reflog_iterator *)ref_iterator;
struct dir_iterator *diter = iter->dir_iterator;
int ok;
while ((ok = dir_iterator_advance(diter)) == ITER_OK) {
int flags;
if (!S_ISREG(diter->st.st_mode))
continue;
if (diter->basename[0] == '.')
continue;
if (ends_with(diter->basename, ".lock"))
continue;
if (read_ref_full(diter->relative_path, 0,
iter->oid.hash, &flags)) {
error("bad ref for %s", diter->path.buf);
continue;
}
if (retval)
break;
iter->base.refname = diter->relative_path;
iter->base.oid = &iter->oid;
iter->base.flags = flags;
return ITER_OK;
}
strbuf_setlen(name, oldlen);
iter->dir_iterator = NULL;
if (ref_iterator_abort(ref_iterator) == ITER_ERROR)
ok = ITER_ERROR;
return ok;
}
closedir(d);
return retval;
static int files_reflog_iterator_peel(struct ref_iterator *ref_iterator,
struct object_id *peeled)
{
die("BUG: ref_iterator_peel() called for reflog_iterator");
}
static int files_reflog_iterator_abort(struct ref_iterator *ref_iterator)
{
struct files_reflog_iterator *iter =
(struct files_reflog_iterator *)ref_iterator;
int ok = ITER_DONE;
if (iter->dir_iterator)
ok = dir_iterator_abort(iter->dir_iterator);
base_ref_iterator_free(ref_iterator);
return ok;
}
static struct ref_iterator_vtable files_reflog_iterator_vtable = {
files_reflog_iterator_advance,
files_reflog_iterator_peel,
files_reflog_iterator_abort
};
struct ref_iterator *files_reflog_iterator_begin(void)
{
struct files_reflog_iterator *iter = xcalloc(1, sizeof(*iter));
struct ref_iterator *ref_iterator = &iter->base;
base_ref_iterator_init(ref_iterator, &files_reflog_iterator_vtable);
iter->dir_iterator = dir_iterator_begin(git_path("logs"));
return ref_iterator;
}
int for_each_reflog(each_ref_fn fn, void *cb_data)
{
int retval;
struct strbuf name;
strbuf_init(&name, PATH_MAX);
retval = do_for_each_reflog(&name, fn, cb_data);
strbuf_release(&name);
return retval;
return do_for_each_ref_iterator(files_reflog_iterator_begin(),
fn, cb_data);
}
static int ref_update_reject_duplicates(struct string_list *refnames,

384
refs/iterator.c Normal file
View File

@ -0,0 +1,384 @@
/*
* Generic reference iterator infrastructure. See refs-internal.h for
* documentation about the design and use of reference iterators.
*/
#include "cache.h"
#include "refs.h"
#include "refs/refs-internal.h"
#include "iterator.h"
int ref_iterator_advance(struct ref_iterator *ref_iterator)
{
return ref_iterator->vtable->advance(ref_iterator);
}
int ref_iterator_peel(struct ref_iterator *ref_iterator,
struct object_id *peeled)
{
return ref_iterator->vtable->peel(ref_iterator, peeled);
}
int ref_iterator_abort(struct ref_iterator *ref_iterator)
{
return ref_iterator->vtable->abort(ref_iterator);
}
void base_ref_iterator_init(struct ref_iterator *iter,
struct ref_iterator_vtable *vtable)
{
iter->vtable = vtable;
iter->refname = NULL;
iter->oid = NULL;
iter->flags = 0;
}
void base_ref_iterator_free(struct ref_iterator *iter)
{
/* Help make use-after-free bugs fail quickly: */
iter->vtable = NULL;
free(iter);
}
struct empty_ref_iterator {
struct ref_iterator base;
};
static int empty_ref_iterator_advance(struct ref_iterator *ref_iterator)
{
return ref_iterator_abort(ref_iterator);
}
static int empty_ref_iterator_peel(struct ref_iterator *ref_iterator,
struct object_id *peeled)
{
die("BUG: peel called for empty iterator");
}
static int empty_ref_iterator_abort(struct ref_iterator *ref_iterator)
{
base_ref_iterator_free(ref_iterator);
return ITER_DONE;
}
static struct ref_iterator_vtable empty_ref_iterator_vtable = {
empty_ref_iterator_advance,
empty_ref_iterator_peel,
empty_ref_iterator_abort
};
struct ref_iterator *empty_ref_iterator_begin(void)
{
struct empty_ref_iterator *iter = xcalloc(1, sizeof(*iter));
struct ref_iterator *ref_iterator = &iter->base;
base_ref_iterator_init(ref_iterator, &empty_ref_iterator_vtable);
return ref_iterator;
}
int is_empty_ref_iterator(struct ref_iterator *ref_iterator)
{
return ref_iterator->vtable == &empty_ref_iterator_vtable;
}
struct merge_ref_iterator {
struct ref_iterator base;
struct ref_iterator *iter0, *iter1;
ref_iterator_select_fn *select;
void *cb_data;
/*
* A pointer to iter0 or iter1 (whichever is supplying the
* current value), or NULL if advance has not yet been called.
*/
struct ref_iterator **current;
};
static int merge_ref_iterator_advance(struct ref_iterator *ref_iterator)
{
struct merge_ref_iterator *iter =
(struct merge_ref_iterator *)ref_iterator;
int ok;
if (!iter->current) {
/* Initialize: advance both iterators to their first entries */
if ((ok = ref_iterator_advance(iter->iter0)) != ITER_OK) {
iter->iter0 = NULL;
if (ok == ITER_ERROR)
goto error;
}
if ((ok = ref_iterator_advance(iter->iter1)) != ITER_OK) {
iter->iter1 = NULL;
if (ok == ITER_ERROR)
goto error;
}
} else {
/*
* Advance the current iterator past the just-used
* entry:
*/
if ((ok = ref_iterator_advance(*iter->current)) != ITER_OK) {
*iter->current = NULL;
if (ok == ITER_ERROR)
goto error;
}
}
/* Loop until we find an entry that we can yield. */
while (1) {
struct ref_iterator **secondary;
enum iterator_selection selection =
iter->select(iter->iter0, iter->iter1, iter->cb_data);
if (selection == ITER_SELECT_DONE) {
return ref_iterator_abort(ref_iterator);
} else if (selection == ITER_SELECT_ERROR) {
ref_iterator_abort(ref_iterator);
return ITER_ERROR;
}
if ((selection & ITER_CURRENT_SELECTION_MASK) == 0) {
iter->current = &iter->iter0;
secondary = &iter->iter1;
} else {
iter->current = &iter->iter1;
secondary = &iter->iter0;
}
if (selection & ITER_SKIP_SECONDARY) {
if ((ok = ref_iterator_advance(*secondary)) != ITER_OK) {
*secondary = NULL;
if (ok == ITER_ERROR)
goto error;
}
}
if (selection & ITER_YIELD_CURRENT) {
iter->base.refname = (*iter->current)->refname;
iter->base.oid = (*iter->current)->oid;
iter->base.flags = (*iter->current)->flags;
return ITER_OK;
}
}
error:
ref_iterator_abort(ref_iterator);
return ITER_ERROR;
}
static int merge_ref_iterator_peel(struct ref_iterator *ref_iterator,
struct object_id *peeled)
{
struct merge_ref_iterator *iter =
(struct merge_ref_iterator *)ref_iterator;
if (!iter->current) {
die("BUG: peel called before advance for merge iterator");
}
return ref_iterator_peel(*iter->current, peeled);
}
static int merge_ref_iterator_abort(struct ref_iterator *ref_iterator)
{
struct merge_ref_iterator *iter =
(struct merge_ref_iterator *)ref_iterator;
int ok = ITER_DONE;
if (iter->iter0) {
if (ref_iterator_abort(iter->iter0) != ITER_DONE)
ok = ITER_ERROR;
}
if (iter->iter1) {
if (ref_iterator_abort(iter->iter1) != ITER_DONE)
ok = ITER_ERROR;
}
base_ref_iterator_free(ref_iterator);
return ok;
}
static struct ref_iterator_vtable merge_ref_iterator_vtable = {
merge_ref_iterator_advance,
merge_ref_iterator_peel,
merge_ref_iterator_abort
};
struct ref_iterator *merge_ref_iterator_begin(
struct ref_iterator *iter0, struct ref_iterator *iter1,
ref_iterator_select_fn *select, void *cb_data)
{
struct merge_ref_iterator *iter = xcalloc(1, sizeof(*iter));
struct ref_iterator *ref_iterator = &iter->base;
/*
* We can't do the same kind of is_empty_ref_iterator()-style
* optimization here as overlay_ref_iterator_begin() does,
* because we don't know the semantics of the select function.
* It might, for example, implement "intersect" by passing
* references through only if they exist in both iterators.
*/
base_ref_iterator_init(ref_iterator, &merge_ref_iterator_vtable);
iter->iter0 = iter0;
iter->iter1 = iter1;
iter->select = select;
iter->cb_data = cb_data;
iter->current = NULL;
return ref_iterator;
}
/*
* A ref_iterator_select_fn that overlays the items from front on top
* of those from back (like loose refs over packed refs). See
* overlay_ref_iterator_begin().
*/
static enum iterator_selection overlay_iterator_select(
struct ref_iterator *front, struct ref_iterator *back,
void *cb_data)
{
int cmp;
if (!back)
return front ? ITER_SELECT_0 : ITER_SELECT_DONE;
else if (!front)
return ITER_SELECT_1;
cmp = strcmp(front->refname, back->refname);
if (cmp < 0)
return ITER_SELECT_0;
else if (cmp > 0)
return ITER_SELECT_1;
else
return ITER_SELECT_0_SKIP_1;
}
struct ref_iterator *overlay_ref_iterator_begin(
struct ref_iterator *front, struct ref_iterator *back)
{
/*
* Optimization: if one of the iterators is empty, return the
* other one rather than incurring the overhead of wrapping
* them.
*/
if (is_empty_ref_iterator(front)) {
ref_iterator_abort(front);
return back;
} else if (is_empty_ref_iterator(back)) {
ref_iterator_abort(back);
return front;
}
return merge_ref_iterator_begin(front, back,
overlay_iterator_select, NULL);
}
struct prefix_ref_iterator {
struct ref_iterator base;
struct ref_iterator *iter0;
char *prefix;
int trim;
};
static int prefix_ref_iterator_advance(struct ref_iterator *ref_iterator)
{
struct prefix_ref_iterator *iter =
(struct prefix_ref_iterator *)ref_iterator;
int ok;
while ((ok = ref_iterator_advance(iter->iter0)) == ITER_OK) {
if (!starts_with(iter->iter0->refname, iter->prefix))
continue;
iter->base.refname = iter->iter0->refname + iter->trim;
iter->base.oid = iter->iter0->oid;
iter->base.flags = iter->iter0->flags;
return ITER_OK;
}
iter->iter0 = NULL;
if (ref_iterator_abort(ref_iterator) != ITER_DONE)
return ITER_ERROR;
return ok;
}
static int prefix_ref_iterator_peel(struct ref_iterator *ref_iterator,
struct object_id *peeled)
{
struct prefix_ref_iterator *iter =
(struct prefix_ref_iterator *)ref_iterator;
return ref_iterator_peel(iter->iter0, peeled);
}
static int prefix_ref_iterator_abort(struct ref_iterator *ref_iterator)
{
struct prefix_ref_iterator *iter =
(struct prefix_ref_iterator *)ref_iterator;
int ok = ITER_DONE;
if (iter->iter0)
ok = ref_iterator_abort(iter->iter0);
free(iter->prefix);
base_ref_iterator_free(ref_iterator);
return ok;
}
static struct ref_iterator_vtable prefix_ref_iterator_vtable = {
prefix_ref_iterator_advance,
prefix_ref_iterator_peel,
prefix_ref_iterator_abort
};
struct ref_iterator *prefix_ref_iterator_begin(struct ref_iterator *iter0,
const char *prefix,
int trim)
{
struct prefix_ref_iterator *iter;
struct ref_iterator *ref_iterator;
if (!*prefix && !trim)
return iter0; /* optimization: no need to wrap iterator */
iter = xcalloc(1, sizeof(*iter));
ref_iterator = &iter->base;
base_ref_iterator_init(ref_iterator, &prefix_ref_iterator_vtable);
iter->iter0 = iter0;
iter->prefix = xstrdup(prefix);
iter->trim = trim;
return ref_iterator;
}
struct ref_iterator *current_ref_iter = NULL;
int do_for_each_ref_iterator(struct ref_iterator *iter,
each_ref_fn fn, void *cb_data)
{
int retval = 0, ok;
struct ref_iterator *old_ref_iter = current_ref_iter;
current_ref_iter = iter;
while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
retval = fn(iter->refname, iter->oid, iter->flags, cb_data);
if (retval) {
/*
* If ref_iterator_abort() returns ITER_ERROR,
* we ignore that error in deference to the
* callback function's return value.
*/
ref_iterator_abort(iter);
goto out;
}
}
out:
current_ref_iter = old_ref_iter;
if (ok == ITER_ERROR)
return -1;
return retval;
}

View File

@ -249,10 +249,230 @@ int rename_ref_available(const char *oldname, const char *newname);
#define DO_FOR_EACH_INCLUDE_BROKEN 0x01
/*
* The common backend for the for_each_*ref* functions
* Reference iterators
*
* A reference iterator encapsulates the state of an in-progress
* iteration over references. Create an instance of `struct
* ref_iterator` via one of the functions in this module.
*
* A freshly-created ref_iterator doesn't yet point at a reference. To
* advance the iterator, call ref_iterator_advance(). If successful,
* this sets the iterator's refname, oid, and flags fields to describe
* the next reference and returns ITER_OK. The data pointed at by
* refname and oid belong to the iterator; if you want to retain them
* after calling ref_iterator_advance() again or calling
* ref_iterator_abort(), you must make a copy. When the iteration has
* been exhausted, ref_iterator_advance() releases any resources
* assocated with the iteration, frees the ref_iterator object, and
* returns ITER_DONE. If you want to abort the iteration early, call
* ref_iterator_abort(), which also frees the ref_iterator object and
* any associated resources. If there was an internal error advancing
* to the next entry, ref_iterator_advance() aborts the iteration,
* frees the ref_iterator, and returns ITER_ERROR.
*
* The reference currently being looked at can be peeled by calling
* ref_iterator_peel(). This function is often faster than peel_ref(),
* so it should be preferred when iterating over references.
*
* Putting it all together, a typical iteration looks like this:
*
* int ok;
* struct ref_iterator *iter = ...;
*
* while ((ok = ref_iterator_advance(iter)) == ITER_OK) {
* if (want_to_stop_iteration()) {
* ok = ref_iterator_abort(iter);
* break;
* }
*
* // Access information about the current reference:
* if (!(iter->flags & REF_ISSYMREF))
* printf("%s is %s\n", iter->refname, oid_to_hex(&iter->oid));
*
* // If you need to peel the reference:
* ref_iterator_peel(iter, &oid);
* }
*
* if (ok != ITER_DONE)
* handle_error();
*/
int do_for_each_ref(const char *submodule, const char *base,
each_ref_fn fn, int trim, int flags, void *cb_data);
struct ref_iterator {
struct ref_iterator_vtable *vtable;
const char *refname;
const struct object_id *oid;
unsigned int flags;
};
/*
* Advance the iterator to the first or next item and return ITER_OK.
* If the iteration is exhausted, free the resources associated with
* the ref_iterator and return ITER_DONE. On errors, free the iterator
* resources and return ITER_ERROR. It is a bug to use ref_iterator or
* call this function again after it has returned ITER_DONE or
* ITER_ERROR.
*/
int ref_iterator_advance(struct ref_iterator *ref_iterator);
/*
* If possible, peel the reference currently being viewed by the
* iterator. Return 0 on success.
*/
int ref_iterator_peel(struct ref_iterator *ref_iterator,
struct object_id *peeled);
/*
* End the iteration before it has been exhausted, freeing the
* reference iterator and any associated resources and returning
* ITER_DONE. If the abort itself failed, return ITER_ERROR.
*/
int ref_iterator_abort(struct ref_iterator *ref_iterator);
/*
* An iterator over nothing (its first ref_iterator_advance() call
* returns ITER_DONE).
*/
struct ref_iterator *empty_ref_iterator_begin(void);
/*
* Return true iff ref_iterator is an empty_ref_iterator.
*/
int is_empty_ref_iterator(struct ref_iterator *ref_iterator);
/*
* A callback function used to instruct merge_ref_iterator how to
* interleave the entries from iter0 and iter1. The function should
* return one of the constants defined in enum iterator_selection. It
* must not advance either of the iterators itself.
*
* The function must be prepared to handle the case that iter0 and/or
* iter1 is NULL, which indicates that the corresponding sub-iterator
* has been exhausted. Its return value must be consistent with the
* current states of the iterators; e.g., it must not return
* ITER_SKIP_1 if iter1 has already been exhausted.
*/
typedef enum iterator_selection ref_iterator_select_fn(
struct ref_iterator *iter0, struct ref_iterator *iter1,
void *cb_data);
/*
* Iterate over the entries from iter0 and iter1, with the values
* interleaved as directed by the select function. The iterator takes
* ownership of iter0 and iter1 and frees them when the iteration is
* over.
*/
struct ref_iterator *merge_ref_iterator_begin(
struct ref_iterator *iter0, struct ref_iterator *iter1,
ref_iterator_select_fn *select, void *cb_data);
/*
* An iterator consisting of the union of the entries from front and
* back. If there are entries common to the two sub-iterators, use the
* one from front. Each iterator must iterate over its entries in
* strcmp() order by refname for this to work.
*
* The new iterator takes ownership of its arguments and frees them
* when the iteration is over. As a convenience to callers, if front
* or back is an empty_ref_iterator, then abort that one immediately
* and return the other iterator directly, without wrapping it.
*/
struct ref_iterator *overlay_ref_iterator_begin(
struct ref_iterator *front, struct ref_iterator *back);
/*
* Wrap iter0, only letting through the references whose names start
* with prefix. If trim is set, set iter->refname to the name of the
* reference with that many characters trimmed off the front;
* otherwise set it to the full refname. The new iterator takes over
* ownership of iter0 and frees it when iteration is over. It makes
* its own copy of prefix.
*
* As an convenience to callers, if prefix is the empty string and
* trim is zero, this function returns iter0 directly, without
* wrapping it.
*/
struct ref_iterator *prefix_ref_iterator_begin(struct ref_iterator *iter0,
const char *prefix,
int trim);
/*
* Iterate over the packed and loose references in the specified
* submodule that are within find_containing_dir(prefix). If prefix is
* NULL or the empty string, iterate over all references in the
* submodule.
*/
struct ref_iterator *files_ref_iterator_begin(const char *submodule,
const char *prefix,
unsigned int flags);
/*
* Iterate over the references in the main ref_store that have a
* reflog. The paths within a directory are iterated over in arbitrary
* order.
*/
struct ref_iterator *files_reflog_iterator_begin(void);
/* Internal implementation of reference iteration: */
/*
* Base class constructor for ref_iterators. Initialize the
* ref_iterator part of iter, setting its vtable pointer as specified.
* This is meant to be called only by the initializers of derived
* classes.
*/
void base_ref_iterator_init(struct ref_iterator *iter,
struct ref_iterator_vtable *vtable);
/*
* Base class destructor for ref_iterators. Destroy the ref_iterator
* part of iter and shallow-free the object. This is meant to be
* called only by the destructors of derived classes.
*/
void base_ref_iterator_free(struct ref_iterator *iter);
/* Virtual function declarations for ref_iterators: */
typedef int ref_iterator_advance_fn(struct ref_iterator *ref_iterator);
typedef int ref_iterator_peel_fn(struct ref_iterator *ref_iterator,
struct object_id *peeled);
/*
* Implementations of this function should free any resources specific
* to the derived class, then call base_ref_iterator_free() to clean
* up and free the ref_iterator object.
*/
typedef int ref_iterator_abort_fn(struct ref_iterator *ref_iterator);
struct ref_iterator_vtable {
ref_iterator_advance_fn *advance;
ref_iterator_peel_fn *peel;
ref_iterator_abort_fn *abort;
};
/*
* current_ref_iter is a performance hack: when iterating over
* references using the for_each_ref*() functions, current_ref_iter is
* set to the reference iterator before calling the callback function.
* If the callback function calls peel_ref(), then peel_ref() first
* checks whether the reference to be peeled is the one referred to by
* the iterator (it usually is) and if so, asks the iterator for the
* peeled version of the reference if it is available. This avoids a
* refname lookup in a common case. current_ref_iter is set to NULL
* when the iteration is over.
*/
extern struct ref_iterator *current_ref_iter;
/*
* The common backend for the for_each_*ref* functions. Call fn for
* each reference in iter. If the iterator itself ever returns
* ITER_ERROR, return -1. If fn ever returns a non-zero value, stop
* the iteration and return that value. Otherwise, return 0. In any
* case, free the iterator when done. This function is basically an
* adapter between the callback style of reference iteration and the
* iterator style.
*/
int do_for_each_ref_iterator(struct ref_iterator *iter,
each_ref_fn fn, void *cb_data);
/*
* Read the specified reference from the filesystem or packed refs