From c8bae7493d2f2910b57f13ded012e86bdcfb0532 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 16:47:53 +0200 Subject: Adding upstream version 1:2.39.2. Signed-off-by: Daniel Baumann --- sparse-index.c | 605 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 605 insertions(+) create mode 100644 sparse-index.c (limited to 'sparse-index.c') diff --git a/sparse-index.c b/sparse-index.c new file mode 100644 index 0000000..8c269da --- /dev/null +++ b/sparse-index.c @@ -0,0 +1,605 @@ +#include "cache.h" +#include "repository.h" +#include "sparse-index.h" +#include "tree.h" +#include "pathspec.h" +#include "trace2.h" +#include "cache-tree.h" +#include "config.h" +#include "dir.h" +#include "fsmonitor.h" + +struct modify_index_context { + struct index_state *write; + struct pattern_list *pl; +}; + +static struct cache_entry *construct_sparse_dir_entry( + struct index_state *istate, + const char *sparse_dir, + struct cache_tree *tree) +{ + struct cache_entry *de; + + de = make_cache_entry(istate, S_IFDIR, &tree->oid, sparse_dir, 0, 0); + + de->ce_flags |= CE_SKIP_WORKTREE; + return de; +} + +/* + * Returns the number of entries "inserted" into the index. + */ +static int convert_to_sparse_rec(struct index_state *istate, + int num_converted, + int start, int end, + const char *ct_path, size_t ct_pathlen, + struct cache_tree *ct) +{ + int i, can_convert = 1; + int start_converted = num_converted; + struct strbuf child_path = STRBUF_INIT; + + /* + * Is the current path outside of the sparse cone? + * Then check if the region can be replaced by a sparse + * directory entry (everything is sparse and merged). + */ + if (path_in_sparse_checkout(ct_path, istate)) + can_convert = 0; + + for (i = start; can_convert && i < end; i++) { + struct cache_entry *ce = istate->cache[i]; + + if (ce_stage(ce) || + S_ISGITLINK(ce->ce_mode) || + !(ce->ce_flags & CE_SKIP_WORKTREE)) + can_convert = 0; + } + + if (can_convert) { + struct cache_entry *se; + se = construct_sparse_dir_entry(istate, ct_path, ct); + + istate->cache[num_converted++] = se; + return 1; + } + + for (i = start; i < end; ) { + int count, span, pos = -1; + const char *base, *slash; + struct cache_entry *ce = istate->cache[i]; + + /* + * Detect if this is a normal entry outside of any subtree + * entry. + */ + base = ce->name + ct_pathlen; + slash = strchr(base, '/'); + + if (slash) + pos = cache_tree_subtree_pos(ct, base, slash - base); + + if (pos < 0) { + istate->cache[num_converted++] = ce; + i++; + continue; + } + + strbuf_setlen(&child_path, 0); + strbuf_add(&child_path, ce->name, slash - ce->name + 1); + + span = ct->down[pos]->cache_tree->entry_count; + count = convert_to_sparse_rec(istate, + num_converted, i, i + span, + child_path.buf, child_path.len, + ct->down[pos]->cache_tree); + num_converted += count; + i += span; + } + + strbuf_release(&child_path); + return num_converted - start_converted; +} + +int set_sparse_index_config(struct repository *repo, int enable) +{ + int res = repo_config_set_worktree_gently(repo, + "index.sparse", + enable ? "true" : "false"); + prepare_repo_settings(repo); + repo->settings.sparse_index = enable; + return res; +} + +static int index_has_unmerged_entries(struct index_state *istate) +{ + int i; + for (i = 0; i < istate->cache_nr; i++) { + if (ce_stage(istate->cache[i])) + return 1; + } + + return 0; +} + +int is_sparse_index_allowed(struct index_state *istate, int flags) +{ + if (!core_apply_sparse_checkout || !core_sparse_checkout_cone) + return 0; + + if (!istate->repo) + istate->repo = the_repository; + + if (!(flags & SPARSE_INDEX_MEMORY_ONLY)) { + int test_env; + + /* + * The sparse index is not (yet) integrated with a split index. + */ + if (istate->split_index || git_env_bool("GIT_TEST_SPLIT_INDEX", 0)) + return 0; + /* + * The GIT_TEST_SPARSE_INDEX environment variable triggers the + * index.sparse config variable to be on. + */ + test_env = git_env_bool("GIT_TEST_SPARSE_INDEX", -1); + if (test_env >= 0) + set_sparse_index_config(istate->repo, test_env); + + /* + * Only convert to sparse if index.sparse is set. + */ + prepare_repo_settings(istate->repo); + if (!istate->repo->settings.sparse_index) + return 0; + } + + if (init_sparse_checkout_patterns(istate)) + return 0; + + /* + * We need cone-mode patterns to use sparse-index. If a user edits + * their sparse-checkout file manually, then we can detect during + * parsing that they are not actually using cone-mode patterns and + * hence we need to abort this conversion _without error_. Warnings + * already exist in the pattern parsing to inform the user of their + * bad patterns. + */ + if (!istate->sparse_checkout_patterns->use_cone_patterns) + return 0; + + return 1; +} + +int convert_to_sparse(struct index_state *istate, int flags) +{ + /* + * If the index is already sparse, empty, or otherwise + * cannot be converted to sparse, do not convert. + */ + if (istate->sparse_index == INDEX_COLLAPSED || !istate->cache_nr || + !is_sparse_index_allowed(istate, flags)) + return 0; + + /* + * NEEDSWORK: If we have unmerged entries, then stay full. + * Unmerged entries prevent the cache-tree extension from working. + */ + if (index_has_unmerged_entries(istate)) + return 0; + + if (!cache_tree_fully_valid(istate->cache_tree)) { + /* Clear and recompute the cache-tree */ + cache_tree_free(&istate->cache_tree); + + /* + * Silently return if there is a problem with the cache tree update, + * which might just be due to a conflict state in some entry. + * + * This might create new tree objects, so be sure to use + * WRITE_TREE_MISSING_OK. + */ + if (cache_tree_update(istate, WRITE_TREE_MISSING_OK)) + return 0; + } + + remove_fsmonitor(istate); + + trace2_region_enter("index", "convert_to_sparse", istate->repo); + istate->cache_nr = convert_to_sparse_rec(istate, + 0, 0, istate->cache_nr, + "", 0, istate->cache_tree); + + /* Clear and recompute the cache-tree */ + cache_tree_free(&istate->cache_tree); + cache_tree_update(istate, 0); + + istate->fsmonitor_has_run_once = 0; + FREE_AND_NULL(istate->fsmonitor_dirty); + FREE_AND_NULL(istate->fsmonitor_last_update); + + istate->sparse_index = INDEX_COLLAPSED; + trace2_region_leave("index", "convert_to_sparse", istate->repo); + return 0; +} + +static void set_index_entry(struct index_state *istate, int nr, struct cache_entry *ce) +{ + ALLOC_GROW(istate->cache, nr + 1, istate->cache_alloc); + + istate->cache[nr] = ce; + add_name_hash(istate, ce); +} + +static int add_path_to_index(const struct object_id *oid, + struct strbuf *base, const char *path, + unsigned int mode, void *context) +{ + struct modify_index_context *ctx = (struct modify_index_context *)context; + struct cache_entry *ce; + size_t len = base->len; + + if (S_ISDIR(mode)) { + int dtype; + size_t baselen = base->len; + if (!ctx->pl) + return READ_TREE_RECURSIVE; + + /* + * Have we expanded to a point outside of the sparse-checkout? + * + * Artificially pad the path name with a slash "/" to + * indicate it as a directory, and add an arbitrary file + * name ("-") so we can consider base->buf as a file name + * to match against the cone-mode patterns. + * + * If we compared just "path", then we would expand more + * than we should. Since every file at root is always + * included, we would expand every directory at root at + * least one level deep instead of using sparse directory + * entries. + */ + strbuf_addstr(base, path); + strbuf_add(base, "/-", 2); + + if (path_matches_pattern_list(base->buf, base->len, + NULL, &dtype, + ctx->pl, ctx->write)) { + strbuf_setlen(base, baselen); + return READ_TREE_RECURSIVE; + } + + /* + * The path "{base}{path}/" is a sparse directory. Create the correct + * name for inserting the entry into the index. + */ + strbuf_setlen(base, base->len - 1); + } else { + strbuf_addstr(base, path); + } + + ce = make_cache_entry(ctx->write, mode, oid, base->buf, 0, 0); + ce->ce_flags |= CE_SKIP_WORKTREE | CE_EXTENDED; + set_index_entry(ctx->write, ctx->write->cache_nr++, ce); + + strbuf_setlen(base, len); + return 0; +} + +void expand_index(struct index_state *istate, struct pattern_list *pl) +{ + int i; + struct index_state *full; + struct strbuf base = STRBUF_INIT; + const char *tr_region; + struct modify_index_context ctx; + + /* + * If the index is already full, then keep it full. We will convert + * it to a sparse index on write, if possible. + */ + if (!istate || istate->sparse_index == INDEX_EXPANDED) + return; + + /* + * If our index is sparse, but our new pattern set does not use + * cone mode patterns, then we need to expand the index before we + * continue. A NULL pattern set indicates a full expansion to a + * full index. + */ + if (pl && !pl->use_cone_patterns) { + pl = NULL; + } else { + /* + * We might contract file entries into sparse-directory + * entries, and for that we will need the cache tree to + * be recomputed. + */ + cache_tree_free(&istate->cache_tree); + + /* + * If there is a problem creating the cache tree, then we + * need to expand to a full index since we cannot satisfy + * the current request as a sparse index. + */ + if (cache_tree_update(istate, 0)) + pl = NULL; + } + + if (!istate->repo) + istate->repo = the_repository; + + /* + * A NULL pattern set indicates we are expanding a full index, so + * we use a special region name that indicates the full expansion. + * This is used by test cases, but also helps to differentiate the + * two cases. + */ + tr_region = pl ? "expand_index" : "ensure_full_index"; + trace2_region_enter("index", tr_region, istate->repo); + + /* initialize basics of new index */ + full = xcalloc(1, sizeof(struct index_state)); + memcpy(full, istate, sizeof(struct index_state)); + + /* + * This slightly-misnamed 'full' index might still be sparse if we + * are only modifying the list of sparse directories. This hinges + * on whether we have a non-NULL pattern list. + */ + full->sparse_index = pl ? INDEX_PARTIALLY_SPARSE : INDEX_EXPANDED; + + /* then change the necessary things */ + full->cache_alloc = (3 * istate->cache_alloc) / 2; + full->cache_nr = 0; + ALLOC_ARRAY(full->cache, full->cache_alloc); + + ctx.write = full; + ctx.pl = pl; + + for (i = 0; i < istate->cache_nr; i++) { + struct cache_entry *ce = istate->cache[i]; + struct tree *tree; + struct pathspec ps; + int dtype; + + if (!S_ISSPARSEDIR(ce->ce_mode)) { + set_index_entry(full, full->cache_nr++, ce); + continue; + } + + /* We now have a sparse directory entry. Should we expand? */ + if (pl && + path_matches_pattern_list(ce->name, ce->ce_namelen, + NULL, &dtype, + pl, istate) == NOT_MATCHED) { + set_index_entry(full, full->cache_nr++, ce); + continue; + } + + if (!(ce->ce_flags & CE_SKIP_WORKTREE)) + warning(_("index entry is a directory, but not sparse (%08x)"), + ce->ce_flags); + + /* recursively walk into cd->name */ + tree = lookup_tree(istate->repo, &ce->oid); + + memset(&ps, 0, sizeof(ps)); + ps.recursive = 1; + ps.has_wildcard = 1; + ps.max_depth = -1; + + strbuf_setlen(&base, 0); + strbuf_add(&base, ce->name, strlen(ce->name)); + + read_tree_at(istate->repo, tree, &base, &ps, + add_path_to_index, &ctx); + + /* free directory entries. full entries are re-used */ + discard_cache_entry(ce); + } + + /* Copy back into original index. */ + memcpy(&istate->name_hash, &full->name_hash, sizeof(full->name_hash)); + memcpy(&istate->dir_hash, &full->dir_hash, sizeof(full->dir_hash)); + istate->sparse_index = pl ? INDEX_PARTIALLY_SPARSE : INDEX_EXPANDED; + free(istate->cache); + istate->cache = full->cache; + istate->cache_nr = full->cache_nr; + istate->cache_alloc = full->cache_alloc; + istate->fsmonitor_has_run_once = 0; + FREE_AND_NULL(istate->fsmonitor_dirty); + FREE_AND_NULL(istate->fsmonitor_last_update); + + strbuf_release(&base); + free(full); + + /* Clear and recompute the cache-tree */ + cache_tree_free(&istate->cache_tree); + cache_tree_update(istate, 0); + + trace2_region_leave("index", tr_region, istate->repo); +} + +void ensure_full_index(struct index_state *istate) +{ + expand_index(istate, NULL); +} + +void ensure_correct_sparsity(struct index_state *istate) +{ + /* + * If the index can be sparse, make it sparse. Otherwise, + * ensure the index is full. + */ + if (is_sparse_index_allowed(istate, 0)) + convert_to_sparse(istate, 0); + else + ensure_full_index(istate); +} + +static int path_found(const char *path, const char **dirname, size_t *dir_len, + int *dir_found) +{ + struct stat st; + char *newdir; + char *tmp; + + /* + * If dirname corresponds to a directory that doesn't exist, and this + * path starts with dirname, then path can't exist. + */ + if (!*dir_found && !memcmp(path, *dirname, *dir_len)) + return 0; + + /* + * If path itself exists, return 1. + */ + if (!lstat(path, &st)) + return 1; + + /* + * Otherwise, path does not exist so we'll return 0...but we'll first + * determine some info about its parent directory so we can avoid + * lstat calls for future cache entries. + */ + newdir = strrchr(path, '/'); + if (!newdir) + return 0; /* Didn't find a parent dir; just return 0 now. */ + + /* + * If path starts with directory (which we already lstat'ed and found), + * then no need to lstat parent directory again. + */ + if (*dir_found && *dirname && memcmp(path, *dirname, *dir_len)) + return 0; + + /* Free previous dirname, and cache path's dirname */ + *dirname = path; + *dir_len = newdir - path + 1; + + tmp = xstrndup(path, *dir_len); + *dir_found = !lstat(tmp, &st); + free(tmp); + + return 0; +} + +void clear_skip_worktree_from_present_files(struct index_state *istate) +{ + const char *last_dirname = NULL; + size_t dir_len = 0; + int dir_found = 1; + + int i; + int path_count[2] = {0, 0}; + int restarted = 0; + + if (!core_apply_sparse_checkout || + sparse_expect_files_outside_of_patterns) + return; + + trace2_region_enter("index", "clear_skip_worktree_from_present_files", + istate->repo); +restart: + for (i = 0; i < istate->cache_nr; i++) { + struct cache_entry *ce = istate->cache[i]; + + if (ce_skip_worktree(ce)) { + path_count[restarted]++; + if (path_found(ce->name, &last_dirname, &dir_len, &dir_found)) { + if (S_ISSPARSEDIR(ce->ce_mode)) { + if (restarted) + BUG("ensure-full-index did not fully flatten?"); + ensure_full_index(istate); + restarted = 1; + goto restart; + } + ce->ce_flags &= ~CE_SKIP_WORKTREE; + } + } + } + + if (path_count[0]) + trace2_data_intmax("index", istate->repo, + "sparse_path_count", path_count[0]); + if (restarted) + trace2_data_intmax("index", istate->repo, + "sparse_path_count_full", path_count[1]); + trace2_region_leave("index", "clear_skip_worktree_from_present_files", + istate->repo); +} + +/* + * This static global helps avoid infinite recursion between + * expand_to_path() and index_file_exists(). + */ +static int in_expand_to_path = 0; + +void expand_to_path(struct index_state *istate, + const char *path, size_t pathlen, int icase) +{ + struct strbuf path_mutable = STRBUF_INIT; + size_t substr_len; + + /* prevent extra recursion */ + if (in_expand_to_path) + return; + + if (!istate || !istate->sparse_index) + return; + + if (!istate->repo) + istate->repo = the_repository; + + in_expand_to_path = 1; + + /* + * We only need to actually expand a region if the + * following are both true: + * + * 1. 'path' is not already in the index. + * 2. Some parent directory of 'path' is a sparse directory. + */ + + if (index_file_exists(istate, path, pathlen, icase)) + goto cleanup; + + strbuf_add(&path_mutable, path, pathlen); + strbuf_addch(&path_mutable, '/'); + + /* Check the name hash for all parent directories */ + substr_len = 0; + while (substr_len < pathlen) { + char temp; + char *replace = strchr(path_mutable.buf + substr_len, '/'); + + if (!replace) + break; + + /* replace the character _after_ the slash */ + replace++; + temp = *replace; + *replace = '\0'; + if (index_file_exists(istate, path_mutable.buf, + path_mutable.len, icase)) { + /* + * We found a parent directory in the name-hash + * hashtable, because only sparse directory entries + * have a trailing '/' character. Since "path" wasn't + * in the index, perhaps it exists within this + * sparse-directory. Expand accordingly. + */ + ensure_full_index(istate); + break; + } + + *replace = temp; + substr_len = replace - path_mutable.buf; + } + +cleanup: + strbuf_release(&path_mutable); + in_expand_to_path = 0; +} -- cgit v1.2.3