Write the index version 5 file format to disk. This version doesn't
write the cache-tree data and resolve-undo data to the file.
The main work is done when filtering out the directories from the
current in-memory format, where in the same turn also the conflicts
and the file data is calculated.
Helped-by: Thomas Rast <trast@xxxxxxxxxxxxxxx>
Signed-off-by: Thomas Gummerer <t.gummerer@xxxxxxxxx>
---
cache.h | 10 +-
read-cache.c | 587 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
2 files changed, 595 insertions(+), 2 deletions(-)
diff --git a/cache.h b/cache.h
index 98adcd9..f953db4 100644
--- a/cache.h
+++ b/cache.h
@@ -98,7 +98,7 @@ unsigned long git_deflate_bound(git_zstream *, unsigned long);
#define CACHE_SIGNATURE 0x44495243 /* "DIRC" */
#define INDEX_FORMAT_LB 2
-#define INDEX_FORMAT_UB 4
+#define INDEX_FORMAT_UB 5
/*
* The "cache_time" is just the low 32 bits of the
@@ -509,6 +509,7 @@ extern int verify_path(const char *path);
extern struct cache_entry *index_name_exists(struct index_state *istate, const char *name, int namelen, int igncase);
extern int index_name_stage_pos(const struct index_state *, const char *name, int namelen, int stage);
extern int index_name_pos(const struct index_state *, const char *name, int namelen);
+extern struct directory_entry *init_directory_entry(char *pathname, int len);
#define ADD_CACHE_OK_TO_ADD 1 /* Ok to add */
#define ADD_CACHE_OK_TO_REPLACE 2 /* Ok to replace file/directory */
#define ADD_CACHE_SKIP_DFCHECK 4 /* Ok to skip DF conflict checks */
@@ -1243,6 +1244,13 @@ static inline ssize_t write_str_in_full(int fd, const char *str)
return write_in_full(fd, str, strlen(str));
}
+/* index-v5 helper functions */
+extern char *super_directory(const char *filename);
+extern void insert_directory_entry(struct directory_entry *, struct hash_table *, int *, unsigned int *, uint32_t);
+extern void add_conflict_to_directory_entry(struct directory_entry *, struct conflict_entry *);
+extern void add_part_to_conflict_entry(struct directory_entry *, struct conflict_entry *, struct conflict_part *);
+extern struct conflict_entry *create_new_conflict(char *, int, int);
+
/* pager.c */
extern void setup_pager(void);
extern const char *pager_program;
diff --git a/read-cache.c b/read-cache.c
index 21ae804..2c47a97 100644
--- a/read-cache.c
+++ b/read-cache.c
@@ -2204,6 +2204,17 @@ static int ce_write_flush(git_SHA_CTX *context, int fd)
return 0;
}
+static int ce_write_flush_v5(int fd)
+{
+ unsigned int buffered = write_buffer_len;
+ if (buffered) {
+ if (write_in_full(fd, write_buffer, buffered) != buffered)
+ return -1;
+ write_buffer_len = 0;
+ }
+ return 0;
+}
+
static int ce_write_v2(git_SHA_CTX *context, int fd, void *data, unsigned int len)
{
while (len) {
@@ -2226,6 +2237,30 @@ static int ce_write_v2(git_SHA_CTX *context, int fd, void *data, unsigned int le
return 0;
}
+static int ce_write_v5(uint32_t *crc, int fd, void *data, unsigned int len)
+{
+ if (crc)
+ *crc = crc32(*crc, (Bytef*)data, len);
+ while (len) {
+ unsigned int buffered = write_buffer_len;
+ unsigned int partial = WRITE_BUFFER_SIZE - buffered;
+ if (partial > len)
+ partial = len;
+ memcpy(write_buffer + buffered, data, partial);
+ buffered += partial;
+ if (buffered == WRITE_BUFFER_SIZE) {
+ write_buffer_len = buffered;
+ if (ce_write_flush_v5(fd))
+ return -1;
+ buffered = 0;
+ }
+ write_buffer_len = buffered;
+ len -= partial;
+ data = (char *) data + partial;
+ }
+ return 0;
+}
+
static int write_index_ext_header_v2(git_SHA_CTX *context, int fd,
unsigned int ext, unsigned int sz)
{
@@ -2257,6 +2292,19 @@ static int ce_flush(git_SHA_CTX *context, int fd)
return (write_in_full(fd, write_buffer, left) != left) ? -1 : 0;
}
+static int ce_flush_v5(int fd)
+{
+ unsigned int left = write_buffer_len;
+
+ if (left)
+ write_buffer_len = 0;
+
+ if (write_in_full(fd, write_buffer, left) != left)
+ return -1;
+
+ return 0;
+}
+
static void ce_smudge_racily_clean_entry_v2(struct cache_entry *ce)
{
/*
@@ -2306,6 +2354,22 @@ static void ce_smudge_racily_clean_entry_v2(struct cache_entry *ce)
}
}
+static void ce_smudge_racily_clean_entry_v5(struct cache_entry *ce)
+{
+ /*
+ * This method shall only be called if the timestamp of ce
+ * is racy (check with is_racy_timestamp). If the timestamp
+ * is racy, the writer will just set the time to 0.
+ *
+ * The reader (ce_match_stat_basic_v5) will then take care
+ * of checking if the entry is really changed or not, by
+ * taking into account the stat_crc and if that hasn't changed
+ * checking the sha1.
+ */
+ ce->ce_mtime.sec = 0;
+ ce->ce_mtime.nsec = 0;
+}
+
/* Copy miscellaneous fields but not the name */
static char *copy_cache_entry_to_ondisk(struct ondisk_cache_entry *ondisk,
struct cache_entry *ce)
@@ -2489,12 +2553,533 @@ static int write_index_v2(struct index_state *istate, int newfd)
return 0;
}
+char *super_directory(const char *filename)
+{
+ char *slash;
+
+ slash = strrchr(filename, '/');
+ if (slash)
+ return xmemdupz(filename, slash-filename);
+ return NULL;
+}
+
+struct directory_entry *init_directory_entry(char *pathname, int len)
+{
+ struct directory_entry *de = xmalloc(directory_entry_size(len));
+
+ memcpy(de->pathname, pathname, len);
+ de->pathname[len] = '\0';
+ de->de_flags = 0;
+ de->de_foffset = 0;
+ de->de_cr = 0;
+ de->de_ncr = 0;
+ de->de_nsubtrees = 0;
+ de->de_nfiles = 0;
+ de->de_nentries = 0;
+ memset(de->sha1, 0, 20);
+ de->de_pathlen = len;
+ de->next = NULL;
+ de->next_hash = NULL;
+ de->ce = NULL;
+ de->ce_last = NULL;
+ de->conflict = NULL;
+ de->conflict_last = NULL;
+ de->conflict_size = 0;
+ return de;
+}
+
+static void ondisk_from_directory_entry(struct directory_entry *de,
+ struct ondisk_directory_entry *ondisk)
+{
+ ondisk->foffset = htonl(de->de_foffset);
+ ondisk->cr = htonl(de->de_cr);
+ ondisk->ncr = htonl(de->de_ncr);
+ ondisk->nsubtrees = htonl(de->de_nsubtrees);
+ ondisk->nfiles = htonl(de->de_nfiles);
+ ondisk->nentries = htonl(de->de_nentries);
+ hashcpy(ondisk->sha1, de->sha1);
+ ondisk->flags = htons(de->de_flags);
+}
+
+static struct conflict_part *conflict_part_from_inmemory(struct cache_entry *ce)
+{
+ struct conflict_part *conflict;
+ short flags;
+
+ conflict = xmalloc(sizeof(struct conflict_part));
+ flags = CONFLICT_CONFLICTED;
+ flags |= ce_stage(ce) << CONFLICT_STAGESHIFT;
+ conflict->flags = flags;
+ conflict->entry_mode = ce->ce_mode;
+ conflict->next = NULL;
+ hashcpy(conflict->sha1, ce->sha1);
+ return conflict;
+}
+
+static void conflict_to_ondisk(struct conflict_part *cp,
+ struct ondisk_conflict_part *ondisk)
+{
+ ondisk->flags = htons(cp->flags);
+ ondisk->entry_mode = htons(cp->entry_mode);
+ hashcpy(ondisk->sha1, cp->sha1);
+}
+
+void add_conflict_to_directory_entry(struct directory_entry *de,
+ struct conflict_entry *conflict_entry)
+{
+ de->de_ncr++;
+ de->conflict_size += conflict_entry->namelen + 1 + 8 - conflict_entry->pathlen;
+ conflict_entry_push(&de->conflict, &de->conflict_last, conflict_entry);
+}
+
+void insert_directory_entry(struct directory_entry *de,
+ struct hash_table *table,
+ int *total_dir_len,
+ unsigned int *ndir,
+ uint32_t crc)
+{
+ struct directory_entry *insert;
+
+ insert = (struct directory_entry *)insert_hash(crc, de, table);
+ if (insert) {
+ de->next_hash = insert->next_hash;
+ insert->next_hash = de;
+ }
+ (*ndir)++;
+ if (de->de_pathlen == 0)
+ (*total_dir_len)++;
+ else
+ *total_dir_len += de->de_pathlen + 2;
+}
+
+static struct conflict_entry *create_conflict_entry_from_ce(struct cache_entry *ce,
+ int pathlen)
+{
+ return create_new_conflict(ce->name, ce_namelen(ce), pathlen);
+}
+
+static struct directory_entry *compile_directory_data(struct index_state *istate,
+ int nfile,
+ unsigned int *ndir,
+ int *non_conflicted,
+ int *total_dir_len,
+ int *total_file_len)
+{
+ int i, dir_len = -1;
+ char *dir;
+ struct directory_entry *de, *current, *search, *found, *new, *previous_entry;
+ struct cache_entry **cache = istate->cache;
+ struct conflict_entry *conflict_entry;
+ struct hash_table table;
+ uint32_t crc;
+
+ init_hash(&table);
+ de = init_directory_entry("", 0);
+ current = de;
+ *ndir = 1;
+ *total_dir_len = 1;
+ crc = crc32(0, (Bytef*)de->pathname, de->de_pathlen);
+ insert_hash(crc, de, &table);
+ conflict_entry = NULL;
+ for (i = 0; i < nfile; i++) {
+ int new_entry;
+ if (cache[i]->ce_flags & CE_REMOVE)
+ continue;
+
+ new_entry = !ce_stage(cache[i]) || !conflict_entry
+ || cache_name_compare(conflict_entry->name, conflict_entry->namelen,
+ cache[i]->name, ce_namelen(cache[i]));
+ if (new_entry)
+ (*non_conflicted)++;
+ if (dir_len < 0 || strncmp(cache[i]->name, dir, dir_len)
+ || cache[i]->name[dir_len] != '/'
+ || strchr(cache[i]->name + dir_len + 1, '/')) {
+ dir = super_directory(cache[i]->name);
+ if (!dir)
+ dir_len = 0;
+ else
+ dir_len = strlen(dir);
+ crc = crc32(0, (Bytef*)dir, dir_len);
+ found = lookup_hash(crc, &table);
+ search = found;
+ while (search && dir_len != 0 && strcmp(dir, search->pathname) != 0)
+ search = search->next_hash;
+ }
+ previous_entry = current;
+ if (!search || !found) {
+ new = init_directory_entry(dir, dir_len);
+ current->next = new;
+ current = current->next;
+ insert_directory_entry(new, &table, total_dir_len, ndir, crc);
+ search = current;
+ }
+ if (new_entry) {
+ search->de_nfiles++;
+ *total_file_len += ce_namelen(cache[i]) + 1;
+ if (search->de_pathlen)
+ *total_file_len -= search->de_pathlen + 1;
+ ce_queue_push(&(search->ce), &(search->ce_last), cache[i]);
+ }
+ if (ce_stage(cache[i]) > 0) {
+ struct conflict_part *conflict_part;
+ if (new_entry) {
+ conflict_entry = create_conflict_entry_from_ce(cache[i], search->de_pathlen);
+ add_conflict_to_directory_entry(search, conflict_entry);
+ }
+ conflict_part = conflict_part_from_inmemory(cache[i]);
+ add_part_to_conflict_entry(search, conflict_entry, conflict_part);
+ }
+ if (dir && !found) {
+ struct directory_entry *no_subtrees;
+
+ no_subtrees = current;
+ dir = super_directory(dir);
+ if (dir)
+ dir_len = strlen(dir);
+ else
+ dir_len = 0;
+ crc = crc32(0, (Bytef*)dir, dir_len);
+ found = lookup_hash(crc, &table);
+ while (!found) {
+ new = init_directory_entry(dir, dir_len);
+ new->de_nsubtrees = 1;
+ new->next = no_subtrees;
+ no_subtrees = new;
+ insert_directory_entry(new, &table, total_dir_len, ndir, crc);
+ dir = super_directory(dir);
+ if (!dir)
+ dir_len = 0;
+ else
+ dir_len = strlen(dir);
+ crc = crc32(0, (Bytef*)dir, dir_len);
+ found = lookup_hash(crc, &table);
+ }
+ search = found;
+ while (search->next_hash && strcmp(dir, search->pathname) != 0)
+ search = search->next_hash;
+ if (search)
+ found = search;
+ found->de_nsubtrees++;
+ previous_entry->next = no_subtrees;
+ }
+ }
+ return de;
+}
+
+static void ondisk_from_cache_entry(struct cache_entry *ce,
+ struct ondisk_cache_entry_v5 *ondisk)
+{
+ unsigned int flags;
+
+ flags = ce->ce_flags & CE_STAGEMASK;
+ flags |= ce->ce_flags & CE_VALID;
+ if (ce->ce_flags & CE_INTENT_TO_ADD)
+ flags |= CE_INTENT_TO_ADD_V5;
+ if (ce->ce_flags & CE_SKIP_WORKTREE)
+ flags |= CE_SKIP_WORKTREE_V5;
+ ondisk->flags = htons(flags);
+ ondisk->mode = htons(ce->ce_mode);
+ ondisk->mtime.sec = htonl(ce->ce_mtime.sec);
+#ifdef USE_NSEC
+ ondisk->mtime.nsec = htonl(ce->ce_mtime.nsec);
+#else
+ ondisk->mtime.nsec = 0;
+#endif
+ if (!ce->ce_stat_crc)
+ ce->ce_stat_crc = calculate_stat_crc(ce);
+ ondisk->stat_crc = htonl(ce->ce_stat_crc);
+ hashcpy(ondisk->sha1, ce->sha1);
+}
+
+static int write_directories_v5(struct directory_entry *de, int fd, int conflict_offset)
+{
+ struct directory_entry *current;
+ struct ondisk_directory_entry ondisk;
+ int current_offset, offset_write, ondisk_size, foffset;
+ uint32_t crc;
+
+ /*
+ * This is needed because the compiler aligns structs to sizes multipe
+ * of 4
+ */
+ ondisk_size = sizeof(ondisk.flags)
+ + sizeof(ondisk.foffset)
+ + sizeof(ondisk.cr)
+ + sizeof(ondisk.ncr)
+ + sizeof(ondisk.nsubtrees)
+ + sizeof(ondisk.nfiles)
+ + sizeof(ondisk.nentries)
+ + sizeof(ondisk.sha1);
+ current = de;
+ current_offset = 0;
+ foffset = 0;
+ while (current) {
+ int pathlen;
+
+ offset_write = htonl(current_offset);
+ if (ce_write_v5(NULL, fd, &offset_write, 4) < 0)
+ return -1;
+ if (current->de_pathlen == 0)
+ pathlen = 0;
+ else
+ pathlen = current->de_pathlen + 1;
+ current_offset += pathlen + 1 + ondisk_size + 4;
+ current = current->next;
+ }
+ /*
+ * Write one more offset, which points to the end of the entries,
+ * because we use it for calculating the dir length, instead of
+ * using strlen.
+ */
+ offset_write = htonl(current_offset);
+ if (ce_write_v5(NULL, fd, &offset_write, 4) < 0)
+ return -1;
+ current = de;
+ while (current) {
+ crc = 0;
+ if (current->de_pathlen == 0) {
+ if (ce_write_v5(&crc, fd, current->pathname, 1) < 0)
+ return -1;
+ } else {
+ char *path;
+ path = xmalloc(sizeof(char) * (current->de_pathlen + 2));
+ memcpy(path, current->pathname, current->de_pathlen);
+ memcpy(path + current->de_pathlen, "/\0", 2);
+ if (ce_write_v5(&crc, fd, path, current->de_pathlen + 2) < 0)
+ return -1;
+ }
+ current->de_foffset = foffset;
+ current->de_cr = conflict_offset;
+ ondisk_from_directory_entry(current, &ondisk);
+ if (ce_write_v5(&crc, fd, &ondisk, ondisk_size) < 0)
+ return -1;
+ crc = htonl(crc);
+ if (ce_write_v5(NULL, fd, &crc, 4) < 0)
+ return -1;
+ conflict_offset += current->conflict_size;
+ foffset += current->de_nfiles * 4;
+ current = current->next;
+ }
+ return 0;
+}
+
+static int write_entries_v5(struct index_state *istate,
+ struct directory_entry *de,
+ int entries,
+ int fd,
+ int offset_to_offset)
+{
+ int offset, offset_write, ondisk_size;
+ struct directory_entry *current;
+
+ offset = 0;
+ ondisk_size = sizeof(struct ondisk_cache_entry_v5);
+ current = de;
+ while (current) {
+ int pathlen;
+ struct cache_entry *ce = current->ce;
+
+ if (current->de_pathlen == 0)
+ pathlen = 0;
+ else
+ pathlen = current->de_pathlen + 1;
+ while (ce) {
+ if (ce->ce_flags & CE_REMOVE)
+ continue;
+ if (!ce_uptodate(ce) && is_racy_timestamp(istate, ce))
+ ce_smudge_racily_clean_entry_v5(ce);
+
+ offset_write = htonl(offset);
+ if (ce_write_v5(NULL, fd, &offset_write, 4) < 0)
+ return -1;
+ offset += ce_namelen(ce) - pathlen + 1 + ondisk_size + 4;
+ ce = ce->next;
+ }
+ current = current->next;
+ }
+ /*
+ * Write one more offset, which points to the end of the entries,
+ * because we use it for calculating the file length, instead of
+ * using strlen.
+ */
+ offset_write = htonl(offset);
+ if (ce_write_v5(NULL, fd, &offset_write, 4) < 0)
+ return -1;
+
+ offset = offset_to_offset;
+ current = de;
+ while (current) {
+ int pathlen;
+ struct cache_entry *ce = current->ce;
+
+ if (current->de_pathlen == 0)
+ pathlen = 0;
+ else
+ pathlen = current->de_pathlen + 1;
+ while (ce) {
+ struct ondisk_cache_entry_v5 ondisk;
+ uint32_t crc, calc_crc;
+
+ if (ce->ce_flags & CE_REMOVE)
+ continue;
+ calc_crc = htonl(offset);
+ crc = crc32(0, (Bytef*)&calc_crc, 4);
+ if (ce_write_v5(&crc, fd, ce->name + pathlen,
+ ce_namelen(ce) - pathlen + 1) < 0)
+ return -1;
+ ondisk_from_cache_entry(ce, &ondisk);
+ if (ce_write_v5(&crc, fd, &ondisk, ondisk_size) < 0)
+ return -1;
+ crc = htonl(crc);
+ if (ce_write_v5(NULL, fd, &crc, 4) < 0)
+ return -1;
+ offset += 4;
+ ce = ce->next;
+ }
+ current = current->next;
+ }
+ return 0;
+}
+
+static int write_conflict_v5(struct conflict_entry *conflict, int fd)
+{
+ struct conflict_entry *current;
+ struct conflict_part *current_part;
+ uint32_t crc;
+
+ current = conflict;
+ while (current) {
+ unsigned int to_write;
+
+ crc = 0;
+ if (ce_write_v5(&crc, fd,
+ (Bytef*)(current->name + current->pathlen),
+ current->namelen - current->pathlen) < 0)
+ return -1;
+ if (ce_write_v5(&crc, fd, (Bytef*)"\0", 1) < 0)
+ return -1;
+ to_write = htonl(current->nfileconflicts);
+ if (ce_write_v5(&crc, fd, (Bytef*)&to_write, 4) < 0)
+ return -1;
+ current_part = current->entries;
+ while (current_part) {
+ struct ondisk_conflict_part ondisk;
+
+ conflict_to_ondisk(current_part, &ondisk);
+ if (ce_write_v5(&crc, fd, (Bytef*)&ondisk, sizeof(struct ondisk_conflict_part)) < 0)
+ return 0;
+ current_part = current_part->next;
+ }
+ to_write = htonl(crc);
+ if (ce_write_v5(NULL, fd, (Bytef*)&to_write, 4) < 0)
+ return -1;
+ current = current->next;
+ }
+ return 0;
+}
+
+static int write_conflicts_v5(struct index_state *istate,
+ struct directory_entry *de,
+ int fd)
+{
+ struct directory_entry *current;
+
+ current = de;
+ while (current) {
+ if (current->de_ncr != 0) {
+ if (write_conflict_v5(current->conflict, fd) < 0)
+ return -1;
+ }
+ current = current->next;
+ }
+ return 0;
+}
+
+static int write_index_v5(struct index_state *istate, int newfd)
+{
+ struct cache_version_header hdr;
+ struct cache_header_v5 hdr_v5;
+ struct cache_entry **cache = istate->cache;
+ struct directory_entry *de;
+ struct ondisk_directory_entry *ondisk;
+ int entries = istate->cache_nr;
+ int i, removed, non_conflicted, total_dir_len, ondisk_directory_size;
+ int total_file_len, conflict_offset, offset_to_offset;
+ unsigned int ndir;
+ uint32_t crc;
+
+ for (i = removed = 0; i < entries; i++) {
+ if (cache[i]->ce_flags & CE_REMOVE)
+ removed++;
+ }
+ hdr.hdr_signature = htonl(CACHE_SIGNATURE);
+ hdr.hdr_version = htonl(istate->version);
+ hdr_v5.hdr_nfile = htonl(entries - removed);
+ hdr_v5.hdr_nextension = htonl(0); /* Currently no extensions are supported */
+
+ non_conflicted = 0;
+ total_dir_len = 0;
+ total_file_len = 0;
+ de = compile_directory_data(istate, entries, &ndir, &non_conflicted,
+ &total_dir_len, &total_file_len);
+ hdr_v5.hdr_ndir = htonl(ndir);
+
+ /*
+ * This is needed because the compiler aligns structs to sizes multipe
+ * of 4
+ */
+ ondisk_directory_size = sizeof(ondisk->flags)
+ + sizeof(ondisk->foffset)
+ + sizeof(ondisk->cr)
+ + sizeof(ondisk->ncr)
+ + sizeof(ondisk->nsubtrees)
+ + sizeof(ondisk->nfiles)
+ + sizeof(ondisk->nentries)
+ + sizeof(ondisk->sha1);
+ hdr_v5.hdr_fblockoffset = htonl(sizeof(hdr) + sizeof(hdr_v5) + 4
+ + (ndir + 1) * 4
+ + total_dir_len
+ + ndir * (ondisk_directory_size + 4)
+ + (non_conflicted + 1) * 4);
+
+ crc = 0;
+ if (ce_write_v5(&crc, newfd, &hdr, sizeof(hdr)) < 0)
+ return -1;
+ if (ce_write_v5(&crc, newfd, &hdr_v5, sizeof(hdr_v5)) < 0)
+ return -1;
+ crc = htonl(crc);
+ if (ce_write_v5(NULL, newfd, &crc, 4) < 0)
+ return -1;
+
+ conflict_offset = sizeof(hdr) + sizeof(hdr_v5) + 4
+ + (ndir + 1) * 4
+ + total_dir_len
+ + ndir * (ondisk_directory_size + 4)
+ + (non_conflicted + 1) * 4
+ + total_file_len
+ + non_conflicted * (sizeof(struct ondisk_cache_entry_v5) + 4);
+ if (write_directories_v5(de, newfd, conflict_offset) < 0)
+ return -1;
+ offset_to_offset = sizeof(hdr) + sizeof(hdr_v5) + 4
+ + (ndir + 1) * 4
+ + total_dir_len
+ + ndir * (ondisk_directory_size + 4);
+ if (write_entries_v5(istate, de, entries, newfd, offset_to_offset) < 0)
+ return -1;
+ if (write_conflicts_v5(istate, de, newfd) < 0)
+ return -1;
+ return ce_flush_v5(newfd);
+}
+
int write_index(struct index_state *istate, int newfd)
{
if (!istate->version)
istate->version = INDEX_FORMAT_DEFAULT;
- return write_index_v2(istate, newfd);
+ if (istate->version != 5)
+ return write_index_v2(istate, newfd);
+ else
+ return write_index_v5(istate, newfd);
}
/*
--
1.7.10.GIT
--
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