git/tree-walk.c
Junio C Hamano 1002f28a52 Merge branch 'eb/hash-transition'
Work to support a repository that work with both SHA-1 and SHA-256
hash algorithms has started.

* eb/hash-transition: (30 commits)
  t1016-compatObjectFormat: add tests to verify the conversion between objects
  t1006: test oid compatibility with cat-file
  t1006: rename sha1 to oid
  test-lib: compute the compatibility hash so tests may use it
  builtin/ls-tree: let the oid determine the output algorithm
  object-file: handle compat objects in check_object_signature
  tree-walk: init_tree_desc take an oid to get the hash algorithm
  builtin/cat-file: let the oid determine the output algorithm
  rev-parse: add an --output-object-format parameter
  repository: implement extensions.compatObjectFormat
  object-file: update object_info_extended to reencode objects
  object-file-convert: convert commits that embed signed tags
  object-file-convert: convert commit objects when writing
  object-file-convert: don't leak when converting tag objects
  object-file-convert: convert tag objects when writing
  object-file-convert: add a function to convert trees between algorithms
  object: factor out parse_mode out of fast-import and tree-walk into in object.h
  cache: add a function to read an OID of a specific algorithm
  tag: sign both hashes
  commit: export add_header_signature to support handling signatures on tags
  ...
2024-03-28 14:13:50 -07:00

1287 lines
32 KiB
C

#include "git-compat-util.h"
#include "tree-walk.h"
#include "dir.h"
#include "gettext.h"
#include "hex.h"
#include "object-file.h"
#include "object-store-ll.h"
#include "trace2.h"
#include "tree.h"
#include "pathspec.h"
#include "json-writer.h"
#include "environment.h"
static int decode_tree_entry(struct tree_desc *desc, const char *buf, unsigned long size, struct strbuf *err)
{
const char *path;
unsigned int len;
uint16_t mode;
const unsigned hashsz = desc->algo->rawsz;
if (size < hashsz + 3 || buf[size - (hashsz + 1)]) {
strbuf_addstr(err, _("too-short tree object"));
return -1;
}
path = parse_mode(buf, &mode);
if (!path) {
strbuf_addstr(err, _("malformed mode in tree entry"));
return -1;
}
if (!*path) {
strbuf_addstr(err, _("empty filename in tree entry"));
return -1;
}
len = strlen(path) + 1;
/* Initialize the descriptor entry */
desc->entry.path = path;
desc->entry.mode = (desc->flags & TREE_DESC_RAW_MODES) ? mode : canon_mode(mode);
desc->entry.pathlen = len - 1;
oidread_algop(&desc->entry.oid, (const unsigned char *)path + len,
desc->algo);
return 0;
}
static int init_tree_desc_internal(struct tree_desc *desc,
const struct object_id *oid,
const void *buffer, unsigned long size,
struct strbuf *err,
enum tree_desc_flags flags)
{
desc->algo = (oid && oid->algo) ? &hash_algos[oid->algo] : the_hash_algo;
desc->buffer = buffer;
desc->size = size;
desc->flags = flags;
if (size)
return decode_tree_entry(desc, buffer, size, err);
return 0;
}
void init_tree_desc(struct tree_desc *desc, const struct object_id *tree_oid,
const void *buffer, unsigned long size)
{
struct strbuf err = STRBUF_INIT;
if (init_tree_desc_internal(desc, tree_oid, buffer, size, &err, 0))
die("%s", err.buf);
strbuf_release(&err);
}
int init_tree_desc_gently(struct tree_desc *desc, const struct object_id *oid,
const void *buffer, unsigned long size,
enum tree_desc_flags flags)
{
struct strbuf err = STRBUF_INIT;
int result = init_tree_desc_internal(desc, oid, buffer, size, &err, flags);
if (result)
error("%s", err.buf);
strbuf_release(&err);
return result;
}
void *fill_tree_descriptor(struct repository *r,
struct tree_desc *desc,
const struct object_id *oid)
{
unsigned long size = 0;
void *buf = NULL;
if (oid) {
buf = read_object_with_reference(r, oid, OBJ_TREE, &size, NULL);
if (!buf)
die(_("unable to read tree (%s)"), oid_to_hex(oid));
}
init_tree_desc(desc, oid, buf, size);
return buf;
}
static void entry_clear(struct name_entry *a)
{
memset(a, 0, sizeof(*a));
}
static void entry_extract(struct tree_desc *t, struct name_entry *a)
{
*a = t->entry;
}
static int update_tree_entry_internal(struct tree_desc *desc, struct strbuf *err)
{
const void *buf = desc->buffer;
const unsigned char *end = (const unsigned char *)desc->entry.path + desc->entry.pathlen + 1 + desc->algo->rawsz;
unsigned long size = desc->size;
unsigned long len = end - (const unsigned char *)buf;
if (size < len)
die(_("too-short tree file"));
buf = end;
size -= len;
desc->buffer = buf;
desc->size = size;
if (size)
return decode_tree_entry(desc, buf, size, err);
return 0;
}
void update_tree_entry(struct tree_desc *desc)
{
struct strbuf err = STRBUF_INIT;
if (update_tree_entry_internal(desc, &err))
die("%s", err.buf);
strbuf_release(&err);
}
int update_tree_entry_gently(struct tree_desc *desc)
{
struct strbuf err = STRBUF_INIT;
if (update_tree_entry_internal(desc, &err)) {
error("%s", err.buf);
strbuf_release(&err);
/* Stop processing this tree after error */
desc->size = 0;
return -1;
}
strbuf_release(&err);
return 0;
}
int tree_entry(struct tree_desc *desc, struct name_entry *entry)
{
if (!desc->size)
return 0;
*entry = desc->entry;
update_tree_entry(desc);
return 1;
}
int tree_entry_gently(struct tree_desc *desc, struct name_entry *entry)
{
if (!desc->size)
return 0;
*entry = desc->entry;
if (update_tree_entry_gently(desc))
return 0;
return 1;
}
static int traverse_trees_atexit_registered;
static int traverse_trees_count;
static int traverse_trees_cur_depth;
static int traverse_trees_max_depth;
static void trace2_traverse_trees_statistics_atexit(void)
{
struct json_writer jw = JSON_WRITER_INIT;
jw_object_begin(&jw, 0);
jw_object_intmax(&jw, "traverse_trees_count", traverse_trees_count);
jw_object_intmax(&jw, "traverse_trees_max_depth", traverse_trees_max_depth);
jw_end(&jw);
trace2_data_json("traverse_trees", the_repository, "statistics", &jw);
jw_release(&jw);
}
void setup_traverse_info(struct traverse_info *info, const char *base)
{
size_t pathlen = strlen(base);
static struct traverse_info dummy;
memset(info, 0, sizeof(*info));
if (pathlen && base[pathlen-1] == '/')
pathlen--;
info->pathlen = pathlen ? pathlen + 1 : 0;
info->name = base;
info->namelen = pathlen;
if (pathlen)
info->prev = &dummy;
if (trace2_is_enabled() && !traverse_trees_atexit_registered) {
atexit(trace2_traverse_trees_statistics_atexit);
traverse_trees_atexit_registered = 1;
}
}
char *make_traverse_path(char *path, size_t pathlen,
const struct traverse_info *info,
const char *name, size_t namelen)
{
/* Always points to the end of the name we're about to add */
size_t pos = st_add(info->pathlen, namelen);
if (pos >= pathlen)
BUG("too small buffer passed to make_traverse_path");
path[pos] = 0;
for (;;) {
if (pos < namelen)
BUG("traverse_info pathlen does not match strings");
pos -= namelen;
memcpy(path + pos, name, namelen);
if (!pos)
break;
path[--pos] = '/';
if (!info)
BUG("traverse_info ran out of list items");
name = info->name;
namelen = info->namelen;
info = info->prev;
}
return path;
}
void strbuf_make_traverse_path(struct strbuf *out,
const struct traverse_info *info,
const char *name, size_t namelen)
{
size_t len = traverse_path_len(info, namelen);
strbuf_grow(out, len);
make_traverse_path(out->buf + out->len, out->alloc - out->len,
info, name, namelen);
strbuf_setlen(out, out->len + len);
}
struct tree_desc_skip {
struct tree_desc_skip *prev;
const void *ptr;
};
struct tree_desc_x {
struct tree_desc d;
struct tree_desc_skip *skip;
};
static int check_entry_match(const char *a, int a_len, const char *b, int b_len)
{
/*
* The caller wants to pick *a* from a tree or nothing.
* We are looking at *b* in a tree.
*
* (0) If a and b are the same name, we are trivially happy.
*
* There are three possibilities where *a* could be hiding
* behind *b*.
*
* (1) *a* == "t", *b* == "ab" i.e. *b* sorts earlier than *a* no
* matter what.
* (2) *a* == "t", *b* == "t-2" and "t" is a subtree in the tree;
* (3) *a* == "t-2", *b* == "t" and "t-2" is a blob in the tree.
*
* Otherwise we know *a* won't appear in the tree without
* scanning further.
*/
int cmp = name_compare(a, a_len, b, b_len);
/* Most common case first -- reading sync'd trees */
if (!cmp)
return cmp;
if (0 < cmp) {
/* a comes after b; it does not matter if it is case (3)
if (b_len < a_len && !memcmp(a, b, b_len) && a[b_len] < '/')
return 1;
*/
return 1; /* keep looking */
}
/* b comes after a; are we looking at case (2)? */
if (a_len < b_len && !memcmp(a, b, a_len) && b[a_len] < '/')
return 1; /* keep looking */
return -1; /* a cannot appear in the tree */
}
/*
* From the extended tree_desc, extract the first name entry, while
* paying attention to the candidate "first" name. Most importantly,
* when looking for an entry, if there are entries that sorts earlier
* in the tree object representation than that name, skip them and
* process the named entry first. We will remember that we haven't
* processed the first entry yet, and in the later call skip the
* entry we processed early when update_extended_entry() is called.
*
* E.g. if the underlying tree object has these entries:
*
* blob "t-1"
* blob "t-2"
* tree "t"
* blob "t=1"
*
* and the "first" asks for "t", remember that we still need to
* process "t-1" and "t-2" but extract "t". After processing the
* entry "t" from this call, the caller will let us know by calling
* update_extended_entry() that we can remember "t" has been processed
* already.
*/
static void extended_entry_extract(struct tree_desc_x *t,
struct name_entry *a,
const char *first,
int first_len)
{
const char *path;
int len;
struct tree_desc probe;
struct tree_desc_skip *skip;
/*
* Extract the first entry from the tree_desc, but skip the
* ones that we already returned in earlier rounds.
*/
while (1) {
if (!t->d.size) {
entry_clear(a);
break; /* not found */
}
entry_extract(&t->d, a);
for (skip = t->skip; skip; skip = skip->prev)
if (a->path == skip->ptr)
break; /* found */
if (!skip)
break;
/* We have processed this entry already. */
update_tree_entry(&t->d);
}
if (!first || !a->path)
return;
/*
* The caller wants "first" from this tree, or nothing.
*/
path = a->path;
len = tree_entry_len(a);
switch (check_entry_match(first, first_len, path, len)) {
case -1:
entry_clear(a);
case 0:
return;
default:
break;
}
/*
* We need to look-ahead -- we suspect that a subtree whose
* name is "first" may be hiding behind the current entry "path".
*/
probe = t->d;
while (probe.size) {
entry_extract(&probe, a);
path = a->path;
len = tree_entry_len(a);
switch (check_entry_match(first, first_len, path, len)) {
case -1:
entry_clear(a);
case 0:
return;
default:
update_tree_entry(&probe);
break;
}
/* keep looking */
}
entry_clear(a);
}
static void update_extended_entry(struct tree_desc_x *t, struct name_entry *a)
{
if (t->d.entry.path == a->path) {
update_tree_entry(&t->d);
} else {
/* we have returned this entry early */
struct tree_desc_skip *skip = xmalloc(sizeof(*skip));
skip->ptr = a->path;
skip->prev = t->skip;
t->skip = skip;
}
}
static void free_extended_entry(struct tree_desc_x *t)
{
struct tree_desc_skip *p, *s;
for (s = t->skip; s; s = p) {
p = s->prev;
free(s);
}
}
static inline int prune_traversal(struct index_state *istate,
struct name_entry *e,
struct traverse_info *info,
struct strbuf *base,
int still_interesting)
{
if (!info->pathspec || still_interesting == 2)
return 2;
if (still_interesting < 0)
return still_interesting;
return tree_entry_interesting(istate, e, base,
info->pathspec);
}
int traverse_trees(struct index_state *istate,
int n, struct tree_desc *t,
struct traverse_info *info)
{
int ret = 0;
struct name_entry *entry;
int i;
struct tree_desc_x *tx;
struct strbuf base = STRBUF_INIT;
int interesting = 1;
char *traverse_path;
if (traverse_trees_cur_depth > max_allowed_tree_depth)
return error("exceeded maximum allowed tree depth");
traverse_trees_count++;
traverse_trees_cur_depth++;
if (traverse_trees_cur_depth > traverse_trees_max_depth)
traverse_trees_max_depth = traverse_trees_cur_depth;
ALLOC_ARRAY(entry, n);
ALLOC_ARRAY(tx, n);
for (i = 0; i < n; i++) {
tx[i].d = t[i];
tx[i].skip = NULL;
}
if (info->prev) {
strbuf_make_traverse_path(&base, info->prev,
info->name, info->namelen);
strbuf_addch(&base, '/');
traverse_path = xstrndup(base.buf, base.len);
} else {
traverse_path = xstrndup(info->name, info->pathlen);
}
info->traverse_path = traverse_path;
for (;;) {
int trees_used;
unsigned long mask, dirmask;
const char *first = NULL;
int first_len = 0;
struct name_entry *e = NULL;
int len;
for (i = 0; i < n; i++) {
e = entry + i;
extended_entry_extract(tx + i, e, NULL, 0);
}
/*
* A tree may have "t-2" at the current location even
* though it may have "t" that is a subtree behind it,
* and another tree may return "t". We want to grab
* all "t" from all trees to match in such a case.
*/
for (i = 0; i < n; i++) {
e = entry + i;
if (!e->path)
continue;
len = tree_entry_len(e);
if (!first) {
first = e->path;
first_len = len;
continue;
}
if (name_compare(e->path, len, first, first_len) < 0) {
first = e->path;
first_len = len;
}
}
if (first) {
for (i = 0; i < n; i++) {
e = entry + i;
extended_entry_extract(tx + i, e, first, first_len);
/* Cull the ones that are not the earliest */
if (!e->path)
continue;
len = tree_entry_len(e);
if (name_compare(e->path, len, first, first_len))
entry_clear(e);
}
}
/* Now we have in entry[i] the earliest name from the trees */
mask = 0;
dirmask = 0;
for (i = 0; i < n; i++) {
if (!entry[i].path)
continue;
mask |= 1ul << i;
if (S_ISDIR(entry[i].mode))
dirmask |= 1ul << i;
e = &entry[i];
}
if (!mask)
break;
interesting = prune_traversal(istate, e, info, &base, interesting);
if (interesting < 0)
break;
if (interesting) {
trees_used = info->fn(n, mask, dirmask, entry, info);
if (trees_used < 0) {
ret = trees_used;
if (!info->show_all_errors)
break;
}
mask &= trees_used;
}
for (i = 0; i < n; i++)
if (mask & (1ul << i))
update_extended_entry(tx + i, entry + i);
}
for (i = 0; i < n; i++)
free_extended_entry(tx + i);
free(tx);
free(entry);
free(traverse_path);
info->traverse_path = NULL;
strbuf_release(&base);
traverse_trees_cur_depth--;
return ret;
}
struct dir_state {
void *tree;
unsigned long size;
struct object_id oid;
};
static int find_tree_entry(struct repository *r, struct tree_desc *t,
const char *name, struct object_id *result,
unsigned short *mode)
{
int namelen = strlen(name);
while (t->size) {
const char *entry;
struct object_id oid;
int entrylen, cmp;
oidcpy(&oid, tree_entry_extract(t, &entry, mode));
entrylen = tree_entry_len(&t->entry);
update_tree_entry(t);
if (entrylen > namelen)
continue;
cmp = memcmp(name, entry, entrylen);
if (cmp > 0)
continue;
if (cmp < 0)
break;
if (entrylen == namelen) {
oidcpy(result, &oid);
return 0;
}
if (name[entrylen] != '/')
continue;
if (!S_ISDIR(*mode))
break;
if (++entrylen == namelen) {
oidcpy(result, &oid);
return 0;
}
return get_tree_entry(r, &oid, name + entrylen, result, mode);
}
return -1;
}
int get_tree_entry(struct repository *r,
const struct object_id *tree_oid,
const char *name,
struct object_id *oid,
unsigned short *mode)
{
int retval;
void *tree;
unsigned long size;
struct object_id root;
tree = read_object_with_reference(r, tree_oid, OBJ_TREE, &size, &root);
if (!tree)
return -1;
if (name[0] == '\0') {
oidcpy(oid, &root);
free(tree);
return 0;
}
if (!size) {
retval = -1;
} else {
struct tree_desc t;
init_tree_desc(&t, tree_oid, tree, size);
retval = find_tree_entry(r, &t, name, oid, mode);
}
free(tree);
return retval;
}
/*
* This is Linux's built-in max for the number of symlinks to follow.
* That limit, of course, does not affect git, but it's a reasonable
* choice.
*/
#define GET_TREE_ENTRY_FOLLOW_SYMLINKS_MAX_LINKS 40
/**
* Find a tree entry by following symlinks in tree_sha (which is
* assumed to be the root of the repository). In the event that a
* symlink points outside the repository (e.g. a link to /foo or a
* root-level link to ../foo), the portion of the link which is
* outside the repository will be returned in result_path, and *mode
* will be set to 0. It is assumed that result_path is uninitialized.
* If there are no symlinks, or the end result of the symlink chain
* points to an object inside the repository, result will be filled in
* with the sha1 of the found object, and *mode will hold the mode of
* the object.
*
* See the code for enum get_oid_result for a description of
* the return values.
*/
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)
{
int retval = MISSING_OBJECT;
struct dir_state *parents = NULL;
size_t parents_alloc = 0;
size_t i, parents_nr = 0;
struct object_id current_tree_oid;
struct strbuf namebuf = STRBUF_INIT;
struct tree_desc t;
int follows_remaining = GET_TREE_ENTRY_FOLLOW_SYMLINKS_MAX_LINKS;
init_tree_desc(&t, NULL, NULL, 0UL);
strbuf_addstr(&namebuf, name);
oidcpy(&current_tree_oid, tree_oid);
while (1) {
int find_result;
char *first_slash;
char *remainder = NULL;
if (!t.buffer) {
void *tree;
struct object_id root;
unsigned long size;
tree = read_object_with_reference(r,
&current_tree_oid,
OBJ_TREE, &size,
&root);
if (!tree)
goto done;
ALLOC_GROW(parents, parents_nr + 1, parents_alloc);
parents[parents_nr].tree = tree;
parents[parents_nr].size = size;
oidcpy(&parents[parents_nr].oid, &root);
parents_nr++;
if (namebuf.buf[0] == '\0') {
oidcpy(result, &root);
retval = FOUND;
goto done;
}
if (!size)
goto done;
/* descend */
init_tree_desc(&t, &current_tree_oid, tree, size);
}
/* Handle symlinks to e.g. a//b by removing leading slashes */
while (namebuf.buf[0] == '/') {
strbuf_remove(&namebuf, 0, 1);
}
/* Split namebuf into a first component and a remainder */
if ((first_slash = strchr(namebuf.buf, '/'))) {
*first_slash = 0;
remainder = first_slash + 1;
}
if (!strcmp(namebuf.buf, "..")) {
struct dir_state *parent;
/*
* We could end up with .. in the namebuf if it
* appears in a symlink.
*/
if (parents_nr == 1) {
if (remainder)
*first_slash = '/';
strbuf_add(result_path, namebuf.buf,
namebuf.len);
*mode = 0;
retval = FOUND;
goto done;
}
parent = &parents[parents_nr - 1];
free(parent->tree);
parents_nr--;
parent = &parents[parents_nr - 1];
init_tree_desc(&t, &parent->oid, parent->tree, parent->size);
strbuf_remove(&namebuf, 0, remainder ? 3 : 2);
continue;
}
/* We could end up here via a symlink to dir/.. */
if (namebuf.buf[0] == '\0') {
oidcpy(result, &parents[parents_nr - 1].oid);
retval = FOUND;
goto done;
}
/* Look up the first (or only) path component in the tree. */
find_result = find_tree_entry(r, &t, namebuf.buf,
&current_tree_oid, mode);
if (find_result) {
goto done;
}
if (S_ISDIR(*mode)) {
if (!remainder) {
oidcpy(result, &current_tree_oid);
retval = FOUND;
goto done;
}
/* Descend the tree */
t.buffer = NULL;
strbuf_remove(&namebuf, 0,
1 + first_slash - namebuf.buf);
} else if (S_ISREG(*mode)) {
if (!remainder) {
oidcpy(result, &current_tree_oid);
retval = FOUND;
} else {
retval = NOT_DIR;
}
goto done;
} else if (S_ISLNK(*mode)) {
/* Follow a symlink */
unsigned long link_len;
size_t len;
char *contents, *contents_start;
struct dir_state *parent;
enum object_type type;
if (follows_remaining-- == 0) {
/* Too many symlinks followed */
retval = SYMLINK_LOOP;
goto done;
}
/*
* At this point, we have followed at a least
* one symlink, so on error we need to report this.
*/
retval = DANGLING_SYMLINK;
contents = repo_read_object_file(r,
&current_tree_oid, &type,
&link_len);
if (!contents)
goto done;
if (contents[0] == '/') {
strbuf_addstr(result_path, contents);
free(contents);
*mode = 0;
retval = FOUND;
goto done;
}
if (remainder)
len = first_slash - namebuf.buf;
else
len = namebuf.len;
contents_start = contents;
parent = &parents[parents_nr - 1];
init_tree_desc(&t, &parent->oid, parent->tree, parent->size);
strbuf_splice(&namebuf, 0, len,
contents_start, link_len);
if (remainder)
namebuf.buf[link_len] = '/';
free(contents);
}
}
done:
for (i = 0; i < parents_nr; i++)
free(parents[i].tree);
free(parents);
strbuf_release(&namebuf);
return retval;
}
static int match_entry(const struct pathspec_item *item,
const struct name_entry *entry, int pathlen,
const char *match, int matchlen,
enum interesting *never_interesting)
{
int m = -1; /* signals that we haven't called strncmp() */
if (item->magic & PATHSPEC_ICASE)
/*
* "Never interesting" trick requires exact
* matching. We could do something clever with inexact
* matching, but it's trickier (and not to forget that
* strcasecmp is locale-dependent, at least in
* glibc). Just disable it for now. It can't be worse
* than the wildcard's codepath of '[Tt][Hi][Is][Ss]'
* pattern.
*/
*never_interesting = entry_not_interesting;
else if (*never_interesting != entry_not_interesting) {
/*
* We have not seen any match that sorts later
* than the current path.
*/
/*
* Does match sort strictly earlier than path
* with their common parts?
*/
m = strncmp(match, entry->path,
(matchlen < pathlen) ? matchlen : pathlen);
if (m < 0)
return 0;
/*
* If we come here even once, that means there is at
* least one pathspec that would sort equal to or
* later than the path we are currently looking at.
* In other words, if we have never reached this point
* after iterating all pathspecs, it means all
* pathspecs are either outside of base, or inside the
* base but sorts strictly earlier than the current
* one. In either case, they will never match the
* subsequent entries. In such a case, we initialized
* the variable to -1 and that is what will be
* returned, allowing the caller to terminate early.
*/
*never_interesting = entry_not_interesting;
}
if (pathlen > matchlen)
return 0;
if (matchlen > pathlen) {
if (match[pathlen] != '/')
return 0;
/*
* Reject non-directories as partial pathnames, except
* when match is a submodule with a trailing slash and
* nothing else (to handle 'submod/' and 'submod'
* uniformly).
*/
if (!S_ISDIR(entry->mode) &&
(!S_ISGITLINK(entry->mode) || matchlen > pathlen + 1))
return 0;
}
if (m == -1)
/*
* we cheated and did not do strncmp(), so we do
* that here.
*/
m = ps_strncmp(item, match, entry->path, pathlen);
/*
* If common part matched earlier then it is a hit,
* because we rejected the case where path is not a
* leading directory and is shorter than match.
*/
if (!m)
/*
* match_entry does not check if the prefix part is
* matched case-sensitively. If the entry is a
* directory and part of prefix, it'll be rematched
* eventually by basecmp with special treatment for
* the prefix.
*/
return 1;
return 0;
}
/* :(icase)-aware string compare */
static int basecmp(const struct pathspec_item *item,
const char *base, const char *match, int len)
{
if (item->magic & PATHSPEC_ICASE) {
int ret, n = len > item->prefix ? item->prefix : len;
ret = strncmp(base, match, n);
if (ret)
return ret;
base += n;
match += n;
len -= n;
}
return ps_strncmp(item, base, match, len);
}
static int match_dir_prefix(const struct pathspec_item *item,
const char *base,
const char *match, int matchlen)
{
if (basecmp(item, base, match, matchlen))
return 0;
/*
* If the base is a subdirectory of a path which
* was specified, all of them are interesting.
*/
if (!matchlen ||
base[matchlen] == '/' ||
match[matchlen - 1] == '/')
return 1;
/* Just a random prefix match */
return 0;
}
/*
* Perform matching on the leading non-wildcard part of
* pathspec. item->nowildcard_len must be greater than zero. Return
* non-zero if base is matched.
*/
static int match_wildcard_base(const struct pathspec_item *item,
const char *base, int baselen,
int *matched)
{
const char *match = item->match;
/* the wildcard part is not considered in this function */
int matchlen = item->nowildcard_len;
if (baselen) {
int dirlen;
/*
* Return early if base is longer than the
* non-wildcard part but it does not match.
*/
if (baselen >= matchlen) {
*matched = matchlen;
return !basecmp(item, base, match, matchlen);
}
dirlen = matchlen;
while (dirlen && match[dirlen - 1] != '/')
dirlen--;
/*
* Return early if base is shorter than the
* non-wildcard part but it does not match. Note that
* base ends with '/' so we are sure it really matches
* directory
*/
if (basecmp(item, base, match, baselen))
return 0;
*matched = baselen;
} else
*matched = 0;
/*
* we could have checked entry against the non-wildcard part
* that is not in base and does similar never_interesting
* optimization as in match_entry. For now just be happy with
* base comparison.
*/
return entry_interesting;
}
/*
* Is a tree entry interesting given the pathspec we have?
*
* Pre-condition: either baselen == 0 (i.e. empty path)
* or base[baselen-1] == '/' (i.e. with trailing slash).
*/
static enum interesting do_match(struct index_state *istate,
const struct name_entry *entry,
struct strbuf *base,
const struct pathspec *ps,
int exclude)
{
int i;
int pathlen, baselen = base->len;
enum interesting never_interesting = ps->has_wildcard ?
entry_not_interesting : all_entries_not_interesting;
GUARD_PATHSPEC(ps,
PATHSPEC_FROMTOP |
PATHSPEC_MAXDEPTH |
PATHSPEC_LITERAL |
PATHSPEC_GLOB |
PATHSPEC_ICASE |
PATHSPEC_EXCLUDE |
PATHSPEC_ATTR);
if (!ps->nr) {
if (!ps->recursive ||
!(ps->magic & PATHSPEC_MAXDEPTH) ||
ps->max_depth == -1)
return all_entries_interesting;
return within_depth(base->buf, baselen,
!!S_ISDIR(entry->mode),
ps->max_depth) ?
entry_interesting : entry_not_interesting;
}
pathlen = tree_entry_len(entry);
for (i = ps->nr - 1; i >= 0; i--) {
const struct pathspec_item *item = ps->items+i;
const char *match = item->match;
const char *base_str = base->buf;
int matchlen = item->len, matched = 0;
if ((!exclude && item->magic & PATHSPEC_EXCLUDE) ||
( exclude && !(item->magic & PATHSPEC_EXCLUDE)))
continue;
if (baselen >= matchlen) {
/* If it doesn't match, move along... */
if (!match_dir_prefix(item, base_str, match, matchlen))
goto match_wildcards;
if (!ps->recursive ||
!(ps->magic & PATHSPEC_MAXDEPTH) ||
ps->max_depth == -1) {
if (!item->attr_match_nr)
return all_entries_interesting;
else
goto interesting;
}
if (within_depth(base_str + matchlen + 1,
baselen - matchlen - 1,
!!S_ISDIR(entry->mode),
ps->max_depth))
goto interesting;
else
return entry_not_interesting;
}
/* Either there must be no base, or the base must match. */
if (baselen == 0 || !basecmp(item, base_str, match, baselen)) {
if (match_entry(item, entry, pathlen,
match + baselen, matchlen - baselen,
&never_interesting))
goto interesting;
if (item->nowildcard_len < item->len) {
if (!git_fnmatch(item, match + baselen, entry->path,
item->nowildcard_len - baselen))
goto interesting;
/*
* Match all directories. We'll try to
* match files later on.
*/
if (ps->recursive && S_ISDIR(entry->mode))
return entry_interesting;
/*
* When matching against submodules with
* wildcard characters, ensure that the entry
* at least matches up to the first wild
* character. More accurate matching can then
* be performed in the submodule itself.
*/
if (ps->recurse_submodules &&
S_ISGITLINK(entry->mode) &&
!ps_strncmp(item, match + baselen,
entry->path,
item->nowildcard_len - baselen))
goto interesting;
}
continue;
}
match_wildcards:
if (item->nowildcard_len == item->len)
continue;
if (item->nowildcard_len &&
!match_wildcard_base(item, base_str, baselen, &matched))
continue;
/*
* Concatenate base and entry->path into one and do
* fnmatch() on it.
*
* While we could avoid concatenation in certain cases
* [1], which saves a memcpy and potentially a
* realloc, it turns out not worth it. Measurement on
* linux-2.6 does not show any clear improvements,
* partly because of the nowildcard_len optimization
* in git_fnmatch(). Avoid micro-optimizations here.
*
* [1] if match_wildcard_base() says the base
* directory is already matched, we only need to match
* the rest, which is shorter so _in theory_ faster.
*/
strbuf_add(base, entry->path, pathlen);
if (!git_fnmatch(item, match, base->buf,
item->nowildcard_len)) {
strbuf_setlen(base, baselen);
goto interesting;
}
/*
* When matching against submodules with
* wildcard characters, ensure that the entry
* at least matches up to the first wild
* character. More accurate matching can then
* be performed in the submodule itself.
*/
if (ps->recurse_submodules && S_ISGITLINK(entry->mode) &&
!ps_strncmp(item, match, base->buf,
item->nowildcard_len)) {
strbuf_setlen(base, baselen);
goto interesting;
}
strbuf_setlen(base, baselen);
/*
* Match all directories. We'll try to match files
* later on.
* max_depth is ignored but we may consider support it
* in future, see
* https://lore.kernel.org/git/7vmxo5l2g4.fsf@alter.siamese.dyndns.org/
*/
if (ps->recursive && S_ISDIR(entry->mode))
return entry_interesting;
continue;
interesting:
if (item->attr_match_nr) {
int ret;
/*
* Must not return all_entries_not_interesting
* prematurely. We do not know if all entries do not
* match some attributes with current attr API.
*/
never_interesting = entry_not_interesting;
/*
* Consider all directories interesting (because some
* of those files inside may match some attributes
* even though the parent dir does not)
*
* FIXME: attributes _can_ match directories and we
* can probably return all_entries_interesting or
* all_entries_not_interesting here if matched.
*/
if (S_ISDIR(entry->mode))
return entry_interesting;
strbuf_add(base, entry->path, pathlen);
ret = match_pathspec_attrs(istate, base->buf,
base->len, item);
strbuf_setlen(base, baselen);
if (!ret)
continue;
}
return entry_interesting;
}
return never_interesting; /* No matches */
}
/*
* Is a tree entry interesting given the pathspec we have?
*
* Pre-condition: either baselen == 0 (i.e. empty path)
* or base[baselen-1] == '/' (i.e. with trailing slash).
*/
enum interesting tree_entry_interesting(struct index_state *istate,
const struct name_entry *entry,
struct strbuf *base,
const struct pathspec *ps)
{
enum interesting positive, negative;
positive = do_match(istate, entry, base, ps, 0);
/*
* case | entry | positive | negative | result
* -----+-------+----------+----------+-------
* 1 | file | -1 | -1..2 | -1
* 2 | file | 0 | -1..2 | 0
* 3 | file | 1 | -1 | 1
* 4 | file | 1 | 0 | 1
* 5 | file | 1 | 1 | 0
* 6 | file | 1 | 2 | 0
* 7 | file | 2 | -1 | 2
* 8 | file | 2 | 0 | 1
* 9 | file | 2 | 1 | 0
* 10 | file | 2 | 2 | -1
* -----+-------+----------+----------+-------
* 11 | dir | -1 | -1..2 | -1
* 12 | dir | 0 | -1..2 | 0
* 13 | dir | 1 | -1 | 1
* 14 | dir | 1 | 0 | 1
* 15 | dir | 1 | 1 | 1 (*)
* 16 | dir | 1 | 2 | 0
* 17 | dir | 2 | -1 | 2
* 18 | dir | 2 | 0 | 1
* 19 | dir | 2 | 1 | 1 (*)
* 20 | dir | 2 | 2 | -1
*
* (*) An exclude pattern interested in a directory does not
* necessarily mean it will exclude all of the directory. In
* wildcard case, it can't decide until looking at individual
* files inside. So don't write such directories off yet.
*/
if (!(ps->magic & PATHSPEC_EXCLUDE) ||
positive <= entry_not_interesting) /* #1, #2, #11, #12 */
return positive;
negative = do_match(istate, entry, base, ps, 1);
/* #8, #18 */
if (positive == all_entries_interesting &&
negative == entry_not_interesting)
return entry_interesting;
/* #3, #4, #7, #13, #14, #17 */
if (negative <= entry_not_interesting)
return positive;
/* #15, #19 */
if (S_ISDIR(entry->mode) &&
positive >= entry_interesting &&
negative == entry_interesting)
return entry_interesting;
if ((positive == entry_interesting &&
negative >= entry_interesting) || /* #5, #6, #16 */
(positive == all_entries_interesting &&
negative == entry_interesting)) /* #9 */
return entry_not_interesting;
return all_entries_not_interesting; /* #10, #20 */
}