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e5afd4449d
git-commit-vandalism/object-file.c
Martin Ågren e5afd4449d object-file.c: rename from sha1-file.c 
Drop the last remnant of "sha1" in this file and rename it to reflect
that we're not just able to handle SHA-1 these days.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Reviewed-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-01-04 13:01:55 -08:00

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/*
* GIT - The information manager from hell
*
* Copyright (C) Linus Torvalds, 2005
*
* This handles basic git object files - packing, unpacking,
* creation etc.
*/
#include "cache.h"
#include "config.h"
#include "string-list.h"
#include "lockfile.h"
#include "delta.h"
#include "pack.h"
#include "blob.h"
#include "commit.h"
#include "run-command.h"
#include "tag.h"
#include "tree.h"
#include "tree-walk.h"
#include "refs.h"
#include "pack-revindex.h"
#include "sha1-lookup.h"
#include "bulk-checkin.h"
#include "repository.h"
#include "replace-object.h"
#include "streaming.h"
#include "dir.h"
#include "list.h"
#include "mergesort.h"
#include "quote.h"
#include "packfile.h"
#include "object-store.h"
#include "promisor-remote.h"
/* The maximum size for an object header. */
#define MAX_HEADER_LEN 32
#define EMPTY_TREE_SHA1_BIN_LITERAL \
"\x4b\x82\x5d\xc6\x42\xcb\x6e\xb9\xa0\x60" \
"\xe5\x4b\xf8\xd6\x92\x88\xfb\xee\x49\x04"
#define EMPTY_TREE_SHA256_BIN_LITERAL \
"\x6e\xf1\x9b\x41\x22\x5c\x53\x69\xf1\xc1" \
"\x04\xd4\x5d\x8d\x85\xef\xa9\xb0\x57\xb5" \
"\x3b\x14\xb4\xb9\xb9\x39\xdd\x74\xde\xcc" \
"\x53\x21"
#define EMPTY_BLOB_SHA1_BIN_LITERAL \
"\xe6\x9d\xe2\x9b\xb2\xd1\xd6\x43\x4b\x8b" \
"\x29\xae\x77\x5a\xd8\xc2\xe4\x8c\x53\x91"
#define EMPTY_BLOB_SHA256_BIN_LITERAL \
"\x47\x3a\x0f\x4c\x3b\xe8\xa9\x36\x81\xa2" \
"\x67\xe3\xb1\xe9\xa7\xdc\xda\x11\x85\x43" \
"\x6f\xe1\x41\xf7\x74\x91\x20\xa3\x03\x72" \
"\x18\x13"
const struct object_id null_oid;
static const struct object_id empty_tree_oid = {
EMPTY_TREE_SHA1_BIN_LITERAL
};
static const struct object_id empty_blob_oid = {
EMPTY_BLOB_SHA1_BIN_LITERAL
};
static const struct object_id empty_tree_oid_sha256 = {
EMPTY_TREE_SHA256_BIN_LITERAL
};
static const struct object_id empty_blob_oid_sha256 = {
EMPTY_BLOB_SHA256_BIN_LITERAL
};
static void git_hash_sha1_init(git_hash_ctx *ctx)
{
git_SHA1_Init(&ctx->sha1);
}
static void git_hash_sha1_clone(git_hash_ctx *dst, const git_hash_ctx *src)
{
git_SHA1_Clone(&dst->sha1, &src->sha1);
}
static void git_hash_sha1_update(git_hash_ctx *ctx, const void *data, size_t len)
{
git_SHA1_Update(&ctx->sha1, data, len);
}
static void git_hash_sha1_final(unsigned char *hash, git_hash_ctx *ctx)
{
git_SHA1_Final(hash, &ctx->sha1);
}
static void git_hash_sha256_init(git_hash_ctx *ctx)
{
git_SHA256_Init(&ctx->sha256);
}
static void git_hash_sha256_clone(git_hash_ctx *dst, const git_hash_ctx *src)
{
git_SHA256_Clone(&dst->sha256, &src->sha256);
}
static void git_hash_sha256_update(git_hash_ctx *ctx, const void *data, size_t len)
{
git_SHA256_Update(&ctx->sha256, data, len);
}
static void git_hash_sha256_final(unsigned char *hash, git_hash_ctx *ctx)
{
git_SHA256_Final(hash, &ctx->sha256);
}
static void git_hash_unknown_init(git_hash_ctx *ctx)
{
BUG("trying to init unknown hash");
}
static void git_hash_unknown_clone(git_hash_ctx *dst, const git_hash_ctx *src)
{
BUG("trying to clone unknown hash");
}
static void git_hash_unknown_update(git_hash_ctx *ctx, const void *data, size_t len)
{
BUG("trying to update unknown hash");
}
static void git_hash_unknown_final(unsigned char *hash, git_hash_ctx *ctx)
{
BUG("trying to finalize unknown hash");
}
const struct git_hash_algo hash_algos[GIT_HASH_NALGOS] = {
{
NULL,
0x00000000,
0,
0,
0,
git_hash_unknown_init,
git_hash_unknown_clone,
git_hash_unknown_update,
git_hash_unknown_final,
NULL,
NULL,
},
{
"sha1",
/* "sha1", big-endian */
0x73686131,
GIT_SHA1_RAWSZ,
GIT_SHA1_HEXSZ,
GIT_SHA1_BLKSZ,
git_hash_sha1_init,
git_hash_sha1_clone,
git_hash_sha1_update,
git_hash_sha1_final,
&empty_tree_oid,
&empty_blob_oid,
},
{
"sha256",
/* "s256", big-endian */
0x73323536,
GIT_SHA256_RAWSZ,
GIT_SHA256_HEXSZ,
GIT_SHA256_BLKSZ,
git_hash_sha256_init,
git_hash_sha256_clone,
git_hash_sha256_update,
git_hash_sha256_final,
&empty_tree_oid_sha256,
&empty_blob_oid_sha256,
}
};
const char *empty_tree_oid_hex(void)
{
static char buf[GIT_MAX_HEXSZ + 1];
return oid_to_hex_r(buf, the_hash_algo->empty_tree);
}
const char *empty_blob_oid_hex(void)
{
static char buf[GIT_MAX_HEXSZ + 1];
return oid_to_hex_r(buf, the_hash_algo->empty_blob);
}
int hash_algo_by_name(const char *name)
{
int i;
if (!name)
return GIT_HASH_UNKNOWN;
for (i = 1; i < GIT_HASH_NALGOS; i++)
if (!strcmp(name, hash_algos[i].name))
return i;
return GIT_HASH_UNKNOWN;
}
int hash_algo_by_id(uint32_t format_id)
{
int i;
for (i = 1; i < GIT_HASH_NALGOS; i++)
if (format_id == hash_algos[i].format_id)
return i;
return GIT_HASH_UNKNOWN;
}
int hash_algo_by_length(int len)
{
int i;
for (i = 1; i < GIT_HASH_NALGOS; i++)
if (len == hash_algos[i].rawsz)
return i;
return GIT_HASH_UNKNOWN;
}
/*
* This is meant to hold a *small* number of objects that you would
* want read_object_file() to be able to return, but yet you do not want
* to write them into the object store (e.g. a browse-only
* application).
*/
static struct cached_object {
struct object_id oid;
enum object_type type;
void *buf;
unsigned long size;
} *cached_objects;
static int cached_object_nr, cached_object_alloc;
static struct cached_object empty_tree = {
{ EMPTY_TREE_SHA1_BIN_LITERAL },
OBJ_TREE,
"",
0
};
static struct cached_object *find_cached_object(const struct object_id *oid)
{
int i;
struct cached_object *co = cached_objects;
for (i = 0; i < cached_object_nr; i++, co++) {
if (oideq(&co->oid, oid))
return co;
}
if (oideq(oid, the_hash_algo->empty_tree))
return &empty_tree;
return NULL;
}
static int get_conv_flags(unsigned flags)
{
if (flags & HASH_RENORMALIZE)
return CONV_EOL_RENORMALIZE;
else if (flags & HASH_WRITE_OBJECT)
return global_conv_flags_eol | CONV_WRITE_OBJECT;
else
return 0;
}
int mkdir_in_gitdir(const char *path)
{
if (mkdir(path, 0777)) {
int saved_errno = errno;
struct stat st;
struct strbuf sb = STRBUF_INIT;
if (errno != EEXIST)
return -1;
/*
* Are we looking at a path in a symlinked worktree
* whose original repository does not yet have it?
* e.g. .git/rr-cache pointing at its original
* repository in which the user hasn't performed any
* conflict resolution yet?
*/
if (lstat(path, &st) || !S_ISLNK(st.st_mode) ||
strbuf_readlink(&sb, path, st.st_size) ||
!is_absolute_path(sb.buf) ||
mkdir(sb.buf, 0777)) {
strbuf_release(&sb);
errno = saved_errno;
return -1;
}
strbuf_release(&sb);
}
return adjust_shared_perm(path);
}
static enum scld_error safe_create_leading_directories_1(char *path, int share)
{
char *next_component = path + offset_1st_component(path);
enum scld_error ret = SCLD_OK;
while (ret == SCLD_OK && next_component) {
struct stat st;
char *slash = next_component, slash_character;
while (*slash && !is_dir_sep(*slash))
slash++;
if (!*slash)
break;
next_component = slash + 1;
while (is_dir_sep(*next_component))
next_component++;
if (!*next_component)
break;
slash_character = *slash;
*slash = '\0';
if (!stat(path, &st)) {
/* path exists */
if (!S_ISDIR(st.st_mode)) {
errno = ENOTDIR;
ret = SCLD_EXISTS;
}
} else if (mkdir(path, 0777)) {
if (errno == EEXIST &&
!stat(path, &st) && S_ISDIR(st.st_mode))
; /* somebody created it since we checked */
else if (errno == ENOENT)
/*
* Either mkdir() failed because
* somebody just pruned the containing
* directory, or stat() failed because
* the file that was in our way was
* just removed. Either way, inform
* the caller that it might be worth
* trying again:
*/
ret = SCLD_VANISHED;
else
ret = SCLD_FAILED;
} else if (share && adjust_shared_perm(path)) {
ret = SCLD_PERMS;
}
*slash = slash_character;
}
return ret;
}
enum scld_error safe_create_leading_directories(char *path)
{
return safe_create_leading_directories_1(path, 1);
}
enum scld_error safe_create_leading_directories_no_share(char *path)
{
return safe_create_leading_directories_1(path, 0);
}
enum scld_error safe_create_leading_directories_const(const char *path)
{
int save_errno;
/* path points to cache entries, so xstrdup before messing with it */
char *buf = xstrdup(path);
enum scld_error result = safe_create_leading_directories(buf);
save_errno = errno;
free(buf);
errno = save_errno;
return result;
}
int raceproof_create_file(const char *path, create_file_fn fn, void *cb)
{
/*
* The number of times we will try to remove empty directories
* in the way of path. This is only 1 because if another
* process is racily creating directories that conflict with
* us, we don't want to fight against them.
*/
int remove_directories_remaining = 1;
/*
* The number of times that we will try to create the
* directories containing path. We are willing to attempt this
* more than once, because another process could be trying to
* clean up empty directories at the same time as we are
* trying to create them.
*/
int create_directories_remaining = 3;
/* A scratch copy of path, filled lazily if we need it: */
struct strbuf path_copy = STRBUF_INIT;
int ret, save_errno;
/* Sanity check: */
assert(*path);
retry_fn:
ret = fn(path, cb);
save_errno = errno;
if (!ret)
goto out;
if (errno == EISDIR && remove_directories_remaining-- > 0) {
/*
* A directory is in the way. Maybe it is empty; try
* to remove it:
*/
if (!path_copy.len)
strbuf_addstr(&path_copy, path);
if (!remove_dir_recursively(&path_copy, REMOVE_DIR_EMPTY_ONLY))
goto retry_fn;
} else if (errno == ENOENT && create_directories_remaining-- > 0) {
/*
* Maybe the containing directory didn't exist, or
* maybe it was just deleted by a process that is
* racing with us to clean up empty directories. Try
* to create it:
*/
enum scld_error scld_result;
if (!path_copy.len)
strbuf_addstr(&path_copy, path);
do {
scld_result = safe_create_leading_directories(path_copy.buf);
if (scld_result == SCLD_OK)
goto retry_fn;
} while (scld_result == SCLD_VANISHED && create_directories_remaining-- > 0);
}
out:
strbuf_release(&path_copy);
errno = save_errno;
return ret;
}
static void fill_loose_path(struct strbuf *buf, const struct object_id *oid)
{
int i;
for (i = 0; i < the_hash_algo->rawsz; i++) {
static char hex[] = "0123456789abcdef";
unsigned int val = oid->hash[i];
strbuf_addch(buf, hex[val >> 4]);
strbuf_addch(buf, hex[val & 0xf]);
if (!i)
strbuf_addch(buf, '/');
}
}
static const char *odb_loose_path(struct object_directory *odb,
struct strbuf *buf,
const struct object_id *oid)
{
strbuf_reset(buf);
strbuf_addstr(buf, odb->path);
strbuf_addch(buf, '/');
fill_loose_path(buf, oid);
return buf->buf;
}
const char *loose_object_path(struct repository *r, struct strbuf *buf,
const struct object_id *oid)
{
return odb_loose_path(r->objects->odb, buf, oid);
}
/*
* Return non-zero iff the path is usable as an alternate object database.
*/
static int alt_odb_usable(struct raw_object_store *o,
struct strbuf *path,
const char *normalized_objdir)
{
struct object_directory *odb;
/* Detect cases where alternate disappeared */
if (!is_directory(path->buf)) {
error(_("object directory %s does not exist; "
"check .git/objects/info/alternates"),
path->buf);
return 0;
}
/*
* Prevent the common mistake of listing the same
* thing twice, or object directory itself.
*/
for (odb = o->odb; odb; odb = odb->next) {
if (!fspathcmp(path->buf, odb->path))
return 0;
}
if (!fspathcmp(path->buf, normalized_objdir))
return 0;
return 1;
}
/*
* Prepare alternate object database registry.
*
* The variable alt_odb_list points at the list of struct
* object_directory. The elements on this list come from
* non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
* environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
* whose contents is similar to that environment variable but can be
* LF separated. Its base points at a statically allocated buffer that
* contains "/the/directory/corresponding/to/.git/objects/...", while
* its name points just after the slash at the end of ".git/objects/"
* in the example above, and has enough space to hold all hex characters
* of the object ID, an extra slash for the first level indirection, and
* the terminating NUL.
*/
static void read_info_alternates(struct repository *r,
const char *relative_base,
int depth);
static int link_alt_odb_entry(struct repository *r, const char *entry,
const char *relative_base, int depth, const char *normalized_objdir)
{
struct object_directory *ent;
struct strbuf pathbuf = STRBUF_INIT;
if (!is_absolute_path(entry) && relative_base) {
strbuf_realpath(&pathbuf, relative_base, 1);
strbuf_addch(&pathbuf, '/');
}
strbuf_addstr(&pathbuf, entry);
if (strbuf_normalize_path(&pathbuf) < 0 && relative_base) {
error(_("unable to normalize alternate object path: %s"),
pathbuf.buf);
strbuf_release(&pathbuf);
return -1;
}
/*
* The trailing slash after the directory name is given by
* this function at the end. Remove duplicates.
*/
while (pathbuf.len && pathbuf.buf[pathbuf.len - 1] == '/')
strbuf_setlen(&pathbuf, pathbuf.len - 1);
if (!alt_odb_usable(r->objects, &pathbuf, normalized_objdir)) {
strbuf_release(&pathbuf);
return -1;
}
ent = xcalloc(1, sizeof(*ent));
ent->path = xstrdup(pathbuf.buf);
/* add the alternate entry */
*r->objects->odb_tail = ent;
r->objects->odb_tail = &(ent->next);
ent->next = NULL;
/* recursively add alternates */
read_info_alternates(r, pathbuf.buf, depth + 1);
strbuf_release(&pathbuf);
return 0;
}
static const char *parse_alt_odb_entry(const char *string,
int sep,
struct strbuf *out)
{
const char *end;
strbuf_reset(out);
if (*string == '#') {
/* comment; consume up to next separator */
end = strchrnul(string, sep);
} else if (*string == '"' && !unquote_c_style(out, string, &end)) {
/*
* quoted path; unquote_c_style has copied the
* data for us and set "end". Broken quoting (e.g.,
* an entry that doesn't end with a quote) falls
* back to the unquoted case below.
*/
} else {
/* normal, unquoted path */
end = strchrnul(string, sep);
strbuf_add(out, string, end - string);
}
if (*end)
end++;
return end;
}
static void link_alt_odb_entries(struct repository *r, const char *alt,
int sep, const char *relative_base, int depth)
{
struct strbuf objdirbuf = STRBUF_INIT;
struct strbuf entry = STRBUF_INIT;
if (!alt || !*alt)
return;
if (depth > 5) {
error(_("%s: ignoring alternate object stores, nesting too deep"),
relative_base);
return;
}
strbuf_add_absolute_path(&objdirbuf, r->objects->odb->path);
if (strbuf_normalize_path(&objdirbuf) < 0)
die(_("unable to normalize object directory: %s"),
objdirbuf.buf);
while (*alt) {
alt = parse_alt_odb_entry(alt, sep, &entry);
if (!entry.len)
continue;
link_alt_odb_entry(r, entry.buf,
relative_base, depth, objdirbuf.buf);
}
strbuf_release(&entry);
strbuf_release(&objdirbuf);
}
static void read_info_alternates(struct repository *r,
const char *relative_base,
int depth)
{
char *path;
struct strbuf buf = STRBUF_INIT;
path = xstrfmt("%s/info/alternates", relative_base);
if (strbuf_read_file(&buf, path, 1024) < 0) {
warn_on_fopen_errors(path);
free(path);
return;
}
link_alt_odb_entries(r, buf.buf, '\n', relative_base, depth);
strbuf_release(&buf);
free(path);
}
void add_to_alternates_file(const char *reference)
{
struct lock_file lock = LOCK_INIT;
char *alts = git_pathdup("objects/info/alternates");
FILE *in, *out;
int found = 0;
hold_lock_file_for_update(&lock, alts, LOCK_DIE_ON_ERROR);
out = fdopen_lock_file(&lock, "w");
if (!out)
die_errno(_("unable to fdopen alternates lockfile"));
in = fopen(alts, "r");
if (in) {
struct strbuf line = STRBUF_INIT;
while (strbuf_getline(&line, in) != EOF) {
if (!strcmp(reference, line.buf)) {
found = 1;
break;
}
fprintf_or_die(out, "%s\n", line.buf);
}
strbuf_release(&line);
fclose(in);
}
else if (errno != ENOENT)
die_errno(_("unable to read alternates file"));
if (found) {
rollback_lock_file(&lock);
} else {
fprintf_or_die(out, "%s\n", reference);
if (commit_lock_file(&lock))
die_errno(_("unable to move new alternates file into place"));
if (the_repository->objects->loaded_alternates)
link_alt_odb_entries(the_repository, reference,
'\n', NULL, 0);
}
free(alts);
}
void add_to_alternates_memory(const char *reference)
{
/*
* Make sure alternates are initialized, or else our entry may be
* overwritten when they are.
*/
prepare_alt_odb(the_repository);
link_alt_odb_entries(the_repository, reference,
'\n', NULL, 0);
}
/*
* Compute the exact path an alternate is at and returns it. In case of
* error NULL is returned and the human readable error is added to `err`
* `path` may be relative and should point to $GIT_DIR.
* `err` must not be null.
*/
char *compute_alternate_path(const char *path, struct strbuf *err)
{
char *ref_git = NULL;
const char *repo;
int seen_error = 0;
ref_git = real_pathdup(path, 0);
if (!ref_git) {
seen_error = 1;
strbuf_addf(err, _("path '%s' does not exist"), path);
goto out;
}
repo = read_gitfile(ref_git);
if (!repo)
repo = read_gitfile(mkpath("%s/.git", ref_git));
if (repo) {
free(ref_git);
ref_git = xstrdup(repo);
}
if (!repo && is_directory(mkpath("%s/.git/objects", ref_git))) {
char *ref_git_git = mkpathdup("%s/.git", ref_git);
free(ref_git);
ref_git = ref_git_git;
} else if (!is_directory(mkpath("%s/objects", ref_git))) {
struct strbuf sb = STRBUF_INIT;
seen_error = 1;
if (get_common_dir(&sb, ref_git)) {
strbuf_addf(err,
_("reference repository '%s' as a linked "
"checkout is not supported yet."),
path);
goto out;
}
strbuf_addf(err, _("reference repository '%s' is not a "
"local repository."), path);
goto out;
}
if (!access(mkpath("%s/shallow", ref_git), F_OK)) {
strbuf_addf(err, _("reference repository '%s' is shallow"),
path);
seen_error = 1;
goto out;
}
if (!access(mkpath("%s/info/grafts", ref_git), F_OK)) {
strbuf_addf(err,
_("reference repository '%s' is grafted"),
path);
seen_error = 1;
goto out;
}
out:
if (seen_error) {
FREE_AND_NULL(ref_git);
}
return ref_git;
}
static void fill_alternate_refs_command(struct child_process *cmd,
const char *repo_path)
{
const char *value;
if (!git_config_get_value("core.alternateRefsCommand", &value)) {
cmd->use_shell = 1;
strvec_push(&cmd->args, value);
strvec_push(&cmd->args, repo_path);
} else {
cmd->git_cmd = 1;
strvec_pushf(&cmd->args, "--git-dir=%s", repo_path);
strvec_push(&cmd->args, "for-each-ref");
strvec_push(&cmd->args, "--format=%(objectname)");
if (!git_config_get_value("core.alternateRefsPrefixes", &value)) {
strvec_push(&cmd->args, "--");
strvec_split(&cmd->args, value);
}
}
cmd->env = local_repo_env;
cmd->out = -1;
}
static void read_alternate_refs(const char *path,
alternate_ref_fn *cb,
void *data)
{
struct child_process cmd = CHILD_PROCESS_INIT;
struct strbuf line = STRBUF_INIT;
FILE *fh;
fill_alternate_refs_command(&cmd, path);
if (start_command(&cmd))
return;
fh = xfdopen(cmd.out, "r");
while (strbuf_getline_lf(&line, fh) != EOF) {
struct object_id oid;
const char *p;
if (parse_oid_hex(line.buf, &oid, &p) || *p) {
warning(_("invalid line while parsing alternate refs: %s"),
line.buf);
break;
}
cb(&oid, data);
}
fclose(fh);
finish_command(&cmd);
strbuf_release(&line);
}
struct alternate_refs_data {
alternate_ref_fn *fn;
void *data;
};
static int refs_from_alternate_cb(struct object_directory *e,
void *data)
{
struct strbuf path = STRBUF_INIT;
size_t base_len;
struct alternate_refs_data *cb = data;
if (!strbuf_realpath(&path, e->path, 0))
goto out;
if (!strbuf_strip_suffix(&path, "/objects"))
goto out;
base_len = path.len;
/* Is this a git repository with refs? */
strbuf_addstr(&path, "/refs");
if (!is_directory(path.buf))
goto out;
strbuf_setlen(&path, base_len);
read_alternate_refs(path.buf, cb->fn, cb->data);
out:
strbuf_release(&path);
return 0;
}
void for_each_alternate_ref(alternate_ref_fn fn, void *data)
{
struct alternate_refs_data cb;
cb.fn = fn;
cb.data = data;
foreach_alt_odb(refs_from_alternate_cb, &cb);
}
int foreach_alt_odb(alt_odb_fn fn, void *cb)
{
struct object_directory *ent;
int r = 0;
prepare_alt_odb(the_repository);
for (ent = the_repository->objects->odb->next; ent; ent = ent->next) {
r = fn(ent, cb);
if (r)
break;
}
return r;
}
void prepare_alt_odb(struct repository *r)
{
if (r->objects->loaded_alternates)
return;
link_alt_odb_entries(r, r->objects->alternate_db, PATH_SEP, NULL, 0);
read_info_alternates(r, r->objects->odb->path, 0);
r->objects->loaded_alternates = 1;
}
/* Returns 1 if we have successfully freshened the file, 0 otherwise. */
static int freshen_file(const char *fn)
{
return !utime(fn, NULL);
}
/*
* All of the check_and_freshen functions return 1 if the file exists and was
* freshened (if freshening was requested), 0 otherwise. If they return
* 0, you should not assume that it is safe to skip a write of the object (it
* either does not exist on disk, or has a stale mtime and may be subject to
* pruning).
*/
int check_and_freshen_file(const char *fn, int freshen)
{
if (access(fn, F_OK))
return 0;
if (freshen && !freshen_file(fn))
return 0;
return 1;
}
static int check_and_freshen_odb(struct object_directory *odb,
const struct object_id *oid,
int freshen)
{
static struct strbuf path = STRBUF_INIT;
odb_loose_path(odb, &path, oid);
return check_and_freshen_file(path.buf, freshen);
}
static int check_and_freshen_local(const struct object_id *oid, int freshen)
{
return check_and_freshen_odb(the_repository->objects->odb, oid, freshen);
}
static int check_and_freshen_nonlocal(const struct object_id *oid, int freshen)
{
struct object_directory *odb;
prepare_alt_odb(the_repository);
for (odb = the_repository->objects->odb->next; odb; odb = odb->next) {
if (check_and_freshen_odb(odb, oid, freshen))
return 1;
}
return 0;
}
static int check_and_freshen(const struct object_id *oid, int freshen)
{
return check_and_freshen_local(oid, freshen) ||
check_and_freshen_nonlocal(oid, freshen);
}
int has_loose_object_nonlocal(const struct object_id *oid)
{
return check_and_freshen_nonlocal(oid, 0);
}
static int has_loose_object(const struct object_id *oid)
{
return check_and_freshen(oid, 0);
}
static void mmap_limit_check(size_t length)
{
static size_t limit = 0;
if (!limit) {
limit = git_env_ulong("GIT_MMAP_LIMIT", 0);
if (!limit)
limit = SIZE_MAX;
}
if (length > limit)
die(_("attempting to mmap %"PRIuMAX" over limit %"PRIuMAX),
(uintmax_t)length, (uintmax_t)limit);
}
void *xmmap_gently(void *start, size_t length,
int prot, int flags, int fd, off_t offset)
{
void *ret;
mmap_limit_check(length);
ret = mmap(start, length, prot, flags, fd, offset);
if (ret == MAP_FAILED && !length)
ret = NULL;
return ret;
}
void *xmmap(void *start, size_t length,
int prot, int flags, int fd, off_t offset)
{
void *ret = xmmap_gently(start, length, prot, flags, fd, offset);
if (ret == MAP_FAILED)
die_errno(_("mmap failed"));
return ret;
}
/*
* With an in-core object data in "map", rehash it to make sure the
* object name actually matches "oid" to detect object corruption.
* With "map" == NULL, try reading the object named with "oid" using
* the streaming interface and rehash it to do the same.
*/
int check_object_signature(struct repository *r, const struct object_id *oid,
void *map, unsigned long size, const char *type)
{
struct object_id real_oid;
enum object_type obj_type;
struct git_istream *st;
git_hash_ctx c;
char hdr[MAX_HEADER_LEN];
int hdrlen;
if (map) {
hash_object_file(r->hash_algo, map, size, type, &real_oid);
return !oideq(oid, &real_oid) ? -1 : 0;
}
st = open_istream(r, oid, &obj_type, &size, NULL);
if (!st)
return -1;
/* Generate the header */
hdrlen = xsnprintf(hdr, sizeof(hdr), "%s %"PRIuMAX , type_name(obj_type), (uintmax_t)size) + 1;
/* Sha1.. */
r->hash_algo->init_fn(&c);
r->hash_algo->update_fn(&c, hdr, hdrlen);
for (;;) {
char buf[1024 * 16];
ssize_t readlen = read_istream(st, buf, sizeof(buf));
if (readlen < 0) {
close_istream(st);
return -1;
}
if (!readlen)
break;
r->hash_algo->update_fn(&c, buf, readlen);
}
r->hash_algo->final_fn(real_oid.hash, &c);
close_istream(st);
return !oideq(oid, &real_oid) ? -1 : 0;
}
int git_open_cloexec(const char *name, int flags)
{
int fd;
static int o_cloexec = O_CLOEXEC;
fd = open(name, flags | o_cloexec);
if ((o_cloexec & O_CLOEXEC) && fd < 0 && errno == EINVAL) {
/* Try again w/o O_CLOEXEC: the kernel might not support it */
o_cloexec &= ~O_CLOEXEC;
fd = open(name, flags | o_cloexec);
}
#if defined(F_GETFD) && defined(F_SETFD) && defined(FD_CLOEXEC)
{
static int fd_cloexec = FD_CLOEXEC;
if (!o_cloexec && 0 <= fd && fd_cloexec) {
/* Opened w/o O_CLOEXEC? try with fcntl(2) to add it */
int flags = fcntl(fd, F_GETFD);
if (fcntl(fd, F_SETFD, flags | fd_cloexec))
fd_cloexec = 0;
}
}
#endif
return fd;
}
/*
* Find "oid" as a loose object in the local repository or in an alternate.
* Returns 0 on success, negative on failure.
*
* The "path" out-parameter will give the path of the object we found (if any).
* Note that it may point to static storage and is only valid until another
* call to stat_loose_object().
*/
static int stat_loose_object(struct repository *r, const struct object_id *oid,
struct stat *st, const char **path)
{
struct object_directory *odb;
static struct strbuf buf = STRBUF_INIT;
prepare_alt_odb(r);
for (odb = r->objects->odb; odb; odb = odb->next) {
*path = odb_loose_path(odb, &buf, oid);
if (!lstat(*path, st))
return 0;
}
return -1;
}
/*
* Like stat_loose_object(), but actually open the object and return the
* descriptor. See the caveats on the "path" parameter above.
*/
static int open_loose_object(struct repository *r,
const struct object_id *oid, const char **path)
{
int fd;
struct object_directory *odb;
int most_interesting_errno = ENOENT;
static struct strbuf buf = STRBUF_INIT;
prepare_alt_odb(r);
for (odb = r->objects->odb; odb; odb = odb->next) {
*path = odb_loose_path(odb, &buf, oid);
fd = git_open(*path);
if (fd >= 0)
return fd;
if (most_interesting_errno == ENOENT)
most_interesting_errno = errno;
}
errno = most_interesting_errno;
return -1;
}
static int quick_has_loose(struct repository *r,
const struct object_id *oid)
{
struct object_directory *odb;
prepare_alt_odb(r);
for (odb = r->objects->odb; odb; odb = odb->next) {
if (oid_array_lookup(odb_loose_cache(odb, oid), oid) >= 0)
return 1;
}
return 0;
}
/*
* Map the loose object at "path" if it is not NULL, or the path found by
* searching for a loose object named "oid".
*/
static void *map_loose_object_1(struct repository *r, const char *path,
const struct object_id *oid, unsigned long *size)
{
void *map;
int fd;
if (path)
fd = git_open(path);
else
fd = open_loose_object(r, oid, &path);
map = NULL;
if (fd >= 0) {
struct stat st;
if (!fstat(fd, &st)) {
*size = xsize_t(st.st_size);
if (!*size) {
/* mmap() is forbidden on empty files */
error(_("object file %s is empty"), path);
close(fd);
return NULL;
}
map = xmmap(NULL, *size, PROT_READ, MAP_PRIVATE, fd, 0);
}
close(fd);
}
return map;
}
void *map_loose_object(struct repository *r,
const struct object_id *oid,
unsigned long *size)
{
return map_loose_object_1(r, NULL, oid, size);
}
static int unpack_loose_short_header(git_zstream *stream,
unsigned char *map, unsigned long mapsize,
void *buffer, unsigned long bufsiz)
{
int ret;
/* Get the data stream */
memset(stream, 0, sizeof(*stream));
stream->next_in = map;
stream->avail_in = mapsize;
stream->next_out = buffer;
stream->avail_out = bufsiz;
git_inflate_init(stream);
obj_read_unlock();
ret = git_inflate(stream, 0);
obj_read_lock();
return ret;
}
int unpack_loose_header(git_zstream *stream,
unsigned char *map, unsigned long mapsize,
void *buffer, unsigned long bufsiz)
{
int status = unpack_loose_short_header(stream, map, mapsize,
buffer, bufsiz);
if (status < Z_OK)
return status;
/* Make sure we have the terminating NUL */
if (!memchr(buffer, '\0', stream->next_out - (unsigned char *)buffer))
return -1;
return 0;
}
static int unpack_loose_header_to_strbuf(git_zstream *stream, unsigned char *map,
unsigned long mapsize, void *buffer,
unsigned long bufsiz, struct strbuf *header)
{
int status;
status = unpack_loose_short_header(stream, map, mapsize, buffer, bufsiz);
if (status < Z_OK)
return -1;
/*
* Check if entire header is unpacked in the first iteration.
*/
if (memchr(buffer, '\0', stream->next_out - (unsigned char *)buffer))
return 0;
/*
* buffer[0..bufsiz] was not large enough. Copy the partial
* result out to header, and then append the result of further
* reading the stream.
*/
strbuf_add(header, buffer, stream->next_out - (unsigned char *)buffer);
stream->next_out = buffer;
stream->avail_out = bufsiz;
do {
obj_read_unlock();
status = git_inflate(stream, 0);
obj_read_lock();
strbuf_add(header, buffer, stream->next_out - (unsigned char *)buffer);
if (memchr(buffer, '\0', stream->next_out - (unsigned char *)buffer))
return 0;
stream->next_out = buffer;
stream->avail_out = bufsiz;
} while (status != Z_STREAM_END);
return -1;
}
static void *unpack_loose_rest(git_zstream *stream,
void *buffer, unsigned long size,
const struct object_id *oid)
{
int bytes = strlen(buffer) + 1;
unsigned char *buf = xmallocz(size);
unsigned long n;
int status = Z_OK;
n = stream->total_out - bytes;
if (n > size)
n = size;
memcpy(buf, (char *) buffer + bytes, n);
bytes = n;
if (bytes <= size) {
/*
* The above condition must be (bytes <= size), not
* (bytes < size). In other words, even though we
* expect no more output and set avail_out to zero,
* the input zlib stream may have bytes that express
* "this concludes the stream", and we *do* want to
* eat that input.
*
* Otherwise we would not be able to test that we
* consumed all the input to reach the expected size;
* we also want to check that zlib tells us that all
* went well with status == Z_STREAM_END at the end.
*/
stream->next_out = buf + bytes;
stream->avail_out = size - bytes;
while (status == Z_OK) {
obj_read_unlock();
status = git_inflate(stream, Z_FINISH);
obj_read_lock();
}
}
if (status == Z_STREAM_END && !stream->avail_in) {
git_inflate_end(stream);
return buf;
}
if (status < 0)
error(_("corrupt loose object '%s'"), oid_to_hex(oid));
else if (stream->avail_in)
error(_("garbage at end of loose object '%s'"),
oid_to_hex(oid));
free(buf);
return NULL;
}
/*
* We used to just use "sscanf()", but that's actually way
* too permissive for what we want to check. So do an anal
* object header parse by hand.
*/
static int parse_loose_header_extended(const char *hdr, struct object_info *oi,
unsigned int flags)
{
const char *type_buf = hdr;
unsigned long size;
int type, type_len = 0;
/*
* The type can be of any size but is followed by
* a space.
*/
for (;;) {
char c = *hdr++;
if (!c)
return -1;
if (c == ' ')
break;
type_len++;
}
type = type_from_string_gently(type_buf, type_len, 1);
if (oi->type_name)
strbuf_add(oi->type_name, type_buf, type_len);
/*
* Set type to 0 if its an unknown object and
* we're obtaining the type using '--allow-unknown-type'
* option.
*/
if ((flags & OBJECT_INFO_ALLOW_UNKNOWN_TYPE) && (type < 0))
type = 0;
else if (type < 0)
die(_("invalid object type"));
if (oi->typep)
*oi->typep = type;
/*
* The length must follow immediately, and be in canonical
* decimal format (ie "010" is not valid).
*/
size = *hdr++ - '0';
if (size > 9)
return -1;
if (size) {
for (;;) {
unsigned long c = *hdr - '0';
if (c > 9)
break;
hdr++;
size = size * 10 + c;
}
}
if (oi->sizep)
*oi->sizep = size;
/*
* The length must be followed by a zero byte
*/
return *hdr ? -1 : type;
}
int parse_loose_header(const char *hdr, unsigned long *sizep)
{
struct object_info oi = OBJECT_INFO_INIT;
oi.sizep = sizep;
return parse_loose_header_extended(hdr, &oi, 0);
}
static int loose_object_info(struct repository *r,
const struct object_id *oid,
struct object_info *oi, int flags)
{
int status = 0;
unsigned long mapsize;
void *map;
git_zstream stream;
char hdr[MAX_HEADER_LEN];
struct strbuf hdrbuf = STRBUF_INIT;
unsigned long size_scratch;
if (oi->delta_base_oid)
oidclr(oi->delta_base_oid);
/*
* If we don't care about type or size, then we don't
* need to look inside the object at all. Note that we
* do not optimize out the stat call, even if the
* caller doesn't care about the disk-size, since our
* return value implicitly indicates whether the
* object even exists.
*/
if (!oi->typep && !oi->type_name && !oi->sizep && !oi->contentp) {
const char *path;
struct stat st;
if (!oi->disk_sizep && (flags & OBJECT_INFO_QUICK))
return quick_has_loose(r, oid) ? 0 : -1;
if (stat_loose_object(r, oid, &st, &path) < 0)
return -1;
if (oi->disk_sizep)
*oi->disk_sizep = st.st_size;
return 0;
}
map = map_loose_object(r, oid, &mapsize);
if (!map)
return -1;
if (!oi->sizep)
oi->sizep = &size_scratch;
if (oi->disk_sizep)
*oi->disk_sizep = mapsize;
if ((flags & OBJECT_INFO_ALLOW_UNKNOWN_TYPE)) {
if (unpack_loose_header_to_strbuf(&stream, map, mapsize, hdr, sizeof(hdr), &hdrbuf) < 0)
status = error(_("unable to unpack %s header with --allow-unknown-type"),
oid_to_hex(oid));
} else if (unpack_loose_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
status = error(_("unable to unpack %s header"),
oid_to_hex(oid));
if (status < 0)
; /* Do nothing */
else if (hdrbuf.len) {
if ((status = parse_loose_header_extended(hdrbuf.buf, oi, flags)) < 0)
status = error(_("unable to parse %s header with --allow-unknown-type"),
oid_to_hex(oid));
} else if ((status = parse_loose_header_extended(hdr, oi, flags)) < 0)
status = error(_("unable to parse %s header"), oid_to_hex(oid));
if (status >= 0 && oi->contentp) {
*oi->contentp = unpack_loose_rest(&stream, hdr,
*oi->sizep, oid);
if (!*oi->contentp) {
git_inflate_end(&stream);
status = -1;
}
} else
git_inflate_end(&stream);
munmap(map, mapsize);
if (status && oi->typep)
*oi->typep = status;
if (oi->sizep == &size_scratch)
oi->sizep = NULL;
strbuf_release(&hdrbuf);
oi->whence = OI_LOOSE;
return (status < 0) ? status : 0;
}
int obj_read_use_lock = 0;
pthread_mutex_t obj_read_mutex;
void enable_obj_read_lock(void)
{
if (obj_read_use_lock)
return;
obj_read_use_lock = 1;
init_recursive_mutex(&obj_read_mutex);
}
void disable_obj_read_lock(void)
{
if (!obj_read_use_lock)
return;
obj_read_use_lock = 0;
pthread_mutex_destroy(&obj_read_mutex);
}
int fetch_if_missing = 1;
static int do_oid_object_info_extended(struct repository *r,
const struct object_id *oid,
struct object_info *oi, unsigned flags)
{
static struct object_info blank_oi = OBJECT_INFO_INIT;
struct cached_object *co;
struct pack_entry e;
int rtype;
const struct object_id *real = oid;
int already_retried = 0;
if (flags & OBJECT_INFO_LOOKUP_REPLACE)
real = lookup_replace_object(r, oid);
if (is_null_oid(real))
return -1;
if (!oi)
oi = &blank_oi;
co = find_cached_object(real);
if (co) {
if (oi->typep)
*(oi->typep) = co->type;
if (oi->sizep)
*(oi->sizep) = co->size;
if (oi->disk_sizep)
*(oi->disk_sizep) = 0;
if (oi->delta_base_oid)
oidclr(oi->delta_base_oid);
if (oi->type_name)
strbuf_addstr(oi->type_name, type_name(co->type));
if (oi->contentp)
*oi->contentp = xmemdupz(co->buf, co->size);
oi->whence = OI_CACHED;
return 0;
}
while (1) {
if (find_pack_entry(r, real, &e))
break;
if (flags & OBJECT_INFO_IGNORE_LOOSE)
return -1;
/* Most likely it's a loose object. */
if (!loose_object_info(r, real, oi, flags))
return 0;
/* Not a loose object; someone else may have just packed it. */
if (!(flags & OBJECT_INFO_QUICK)) {
reprepare_packed_git(r);
if (find_pack_entry(r, real, &e))
break;
}
/* Check if it is a missing object */
if (fetch_if_missing && has_promisor_remote() &&
!already_retried && r == the_repository &&
!(flags & OBJECT_INFO_SKIP_FETCH_OBJECT)) {
/*
* TODO Investigate checking promisor_remote_get_direct()
* TODO return value and stopping on error here.
* TODO Pass a repository struct through
* promisor_remote_get_direct(), such that arbitrary
* repositories work.
*/
promisor_remote_get_direct(r, real, 1);
already_retried = 1;
continue;
}
return -1;
}
if (oi == &blank_oi)
/*
* We know that the caller doesn't actually need the
* information below, so return early.
*/
return 0;
rtype = packed_object_info(r, e.p, e.offset, oi);
if (rtype < 0) {
mark_bad_packed_object(e.p, real->hash);
return do_oid_object_info_extended(r, real, oi, 0);
} else if (oi->whence == OI_PACKED) {
oi->u.packed.offset = e.offset;
oi->u.packed.pack = e.p;
oi->u.packed.is_delta = (rtype == OBJ_REF_DELTA ||
rtype == OBJ_OFS_DELTA);
}
return 0;
}
int oid_object_info_extended(struct repository *r, const struct object_id *oid,
struct object_info *oi, unsigned flags)
{
int ret;
obj_read_lock();
ret = do_oid_object_info_extended(r, oid, oi, flags);
obj_read_unlock();
return ret;
}
/* returns enum object_type or negative */
int oid_object_info(struct repository *r,
const struct object_id *oid,
unsigned long *sizep)
{
enum object_type type;
struct object_info oi = OBJECT_INFO_INIT;
oi.typep = &type;
oi.sizep = sizep;
if (oid_object_info_extended(r, oid, &oi,
OBJECT_INFO_LOOKUP_REPLACE) < 0)
return -1;
return type;
}
static void *read_object(struct repository *r,
const struct object_id *oid, enum object_type *type,
unsigned long *size)
{
struct object_info oi = OBJECT_INFO_INIT;
void *content;
oi.typep = type;
oi.sizep = size;
oi.contentp = &content;
if (oid_object_info_extended(r, oid, &oi, 0) < 0)
return NULL;
return content;
}
int pretend_object_file(void *buf, unsigned long len, enum object_type type,
struct object_id *oid)
{
struct cached_object *co;
hash_object_file(the_hash_algo, buf, len, type_name(type), oid);
if (has_object_file_with_flags(oid, OBJECT_INFO_QUICK | OBJECT_INFO_SKIP_FETCH_OBJECT) ||
find_cached_object(oid))
return 0;
ALLOC_GROW(cached_objects, cached_object_nr + 1, cached_object_alloc);
co = &cached_objects[cached_object_nr++];
co->size = len;
co->type = type;
co->buf = xmalloc(len);
memcpy(co->buf, buf, len);
oidcpy(&co->oid, oid);
return 0;
}
/*
* This function dies on corrupt objects; the callers who want to
* deal with them should arrange to call read_object() and give error
* messages themselves.
*/
void *read_object_file_extended(struct repository *r,
const struct object_id *oid,
enum object_type *type,
unsigned long *size,
int lookup_replace)
{
void *data;
const struct packed_git *p;
const char *path;
struct stat st;
const struct object_id *repl = lookup_replace ?
lookup_replace_object(r, oid) : oid;
errno = 0;
data = read_object(r, repl, type, size);
if (data)
return data;
obj_read_lock();
if (errno && errno != ENOENT)
die_errno(_("failed to read object %s"), oid_to_hex(oid));
/* die if we replaced an object with one that does not exist */
if (repl != oid)
die(_("replacement %s not found for %s"),
oid_to_hex(repl), oid_to_hex(oid));
if (!stat_loose_object(r, repl, &st, &path))
die(_("loose object %s (stored in %s) is corrupt"),
oid_to_hex(repl), path);
if ((p = has_packed_and_bad(r, repl->hash)) != NULL)
die(_("packed object %s (stored in %s) is corrupt"),
oid_to_hex(repl), p->pack_name);
obj_read_unlock();
return NULL;
}
void *read_object_with_reference(struct repository *r,
const struct object_id *oid,
const char *required_type_name,
unsigned long *size,
struct object_id *actual_oid_return)
{
enum object_type type, required_type;
void *buffer;
unsigned long isize;
struct object_id actual_oid;
required_type = type_from_string(required_type_name);
oidcpy(&actual_oid, oid);
while (1) {
int ref_length = -1;
const char *ref_type = NULL;
buffer = repo_read_object_file(r, &actual_oid, &type, &isize);
if (!buffer)
return NULL;
if (type == required_type) {
*size = isize;
if (actual_oid_return)
oidcpy(actual_oid_return, &actual_oid);
return buffer;
}
/* Handle references */
else if (type == OBJ_COMMIT)
ref_type = "tree ";
else if (type == OBJ_TAG)
ref_type = "object ";
else {
free(buffer);
return NULL;
}
ref_length = strlen(ref_type);
if (ref_length + the_hash_algo->hexsz > isize ||
memcmp(buffer, ref_type, ref_length) ||
get_oid_hex((char *) buffer + ref_length, &actual_oid)) {
free(buffer);
return NULL;
}
free(buffer);
/* Now we have the ID of the referred-to object in
* actual_oid. Check again. */
}
}
static void write_object_file_prepare(const struct git_hash_algo *algo,
const void *buf, unsigned long len,
const char *type, struct object_id *oid,
char *hdr, int *hdrlen)
{
git_hash_ctx c;
/* Generate the header */
*hdrlen = xsnprintf(hdr, *hdrlen, "%s %"PRIuMAX , type, (uintmax_t)len)+1;
/* Sha1.. */
algo->init_fn(&c);
algo->update_fn(&c, hdr, *hdrlen);
algo->update_fn(&c, buf, len);
algo->final_fn(oid->hash, &c);
}
/*
* Move the just written object into its final resting place.
*/
int finalize_object_file(const char *tmpfile, const char *filename)
{
int ret = 0;
if (object_creation_mode == OBJECT_CREATION_USES_RENAMES)
goto try_rename;
else if (link(tmpfile, filename))
ret = errno;
/*
* Coda hack - coda doesn't like cross-directory links,
* so we fall back to a rename, which will mean that it
* won't be able to check collisions, but that's not a
* big deal.
*
* The same holds for FAT formatted media.
*
* When this succeeds, we just return. We have nothing
* left to unlink.
*/
if (ret && ret != EEXIST) {
try_rename:
if (!rename(tmpfile, filename))
goto out;
ret = errno;
}
unlink_or_warn(tmpfile);
if (ret) {
if (ret != EEXIST) {
return error_errno(_("unable to write file %s"), filename);
}
/* FIXME!!! Collision check here ? */
}
out:
if (adjust_shared_perm(filename))
return error(_("unable to set permission to '%s'"), filename);
return 0;
}
static int write_buffer(int fd, const void *buf, size_t len)
{
if (write_in_full(fd, buf, len) < 0)
return error_errno(_("file write error"));
return 0;
}
int hash_object_file(const struct git_hash_algo *algo, const void *buf,
unsigned long len, const char *type,
struct object_id *oid)
{
char hdr[MAX_HEADER_LEN];
int hdrlen = sizeof(hdr);
write_object_file_prepare(algo, buf, len, type, oid, hdr, &hdrlen);
return 0;
}
/* Finalize a file on disk, and close it. */
static void close_loose_object(int fd)
{
if (fsync_object_files)
fsync_or_die(fd, "loose object file");
if (close(fd) != 0)
die_errno(_("error when closing loose object file"));
}
/* Size of directory component, including the ending '/' */
static inline int directory_size(const char *filename)
{
const char *s = strrchr(filename, '/');
if (!s)
return 0;
return s - filename + 1;
}
/*
* This creates a temporary file in the same directory as the final
* 'filename'
*
* We want to avoid cross-directory filename renames, because those
* can have problems on various filesystems (FAT, NFS, Coda).
*/
static int create_tmpfile(struct strbuf *tmp, const char *filename)
{
int fd, dirlen = directory_size(filename);
strbuf_reset(tmp);
strbuf_add(tmp, filename, dirlen);
strbuf_addstr(tmp, "tmp_obj_XXXXXX");
fd = git_mkstemp_mode(tmp->buf, 0444);
if (fd < 0 && dirlen && errno == ENOENT) {
/*
* Make sure the directory exists; note that the contents
* of the buffer are undefined after mkstemp returns an
* error, so we have to rewrite the whole buffer from
* scratch.
*/
strbuf_reset(tmp);
strbuf_add(tmp, filename, dirlen - 1);
if (mkdir(tmp->buf, 0777) && errno != EEXIST)
return -1;
if (adjust_shared_perm(tmp->buf))
return -1;
/* Try again */
strbuf_addstr(tmp, "/tmp_obj_XXXXXX");
fd = git_mkstemp_mode(tmp->buf, 0444);
}
return fd;
}
static int write_loose_object(const struct object_id *oid, char *hdr,
int hdrlen, const void *buf, unsigned long len,
time_t mtime)
{
int fd, ret;
unsigned char compressed[4096];
git_zstream stream;
git_hash_ctx c;
struct object_id parano_oid;
static struct strbuf tmp_file = STRBUF_INIT;
static struct strbuf filename = STRBUF_INIT;
loose_object_path(the_repository, &filename, oid);
fd = create_tmpfile(&tmp_file, filename.buf);
if (fd < 0) {
if (errno == EACCES)
return error(_("insufficient permission for adding an object to repository database %s"), get_object_directory());
else
return error_errno(_("unable to create temporary file"));
}
/* Set it up */
git_deflate_init(&stream, zlib_compression_level);
stream.next_out = compressed;
stream.avail_out = sizeof(compressed);
the_hash_algo->init_fn(&c);
/* First header.. */
stream.next_in = (unsigned char *)hdr;
stream.avail_in = hdrlen;
while (git_deflate(&stream, 0) == Z_OK)
; /* nothing */
the_hash_algo->update_fn(&c, hdr, hdrlen);
/* Then the data itself.. */
stream.next_in = (void *)buf;
stream.avail_in = len;
do {
unsigned char *in0 = stream.next_in;
ret = git_deflate(&stream, Z_FINISH);
the_hash_algo->update_fn(&c, in0, stream.next_in - in0);
if (write_buffer(fd, compressed, stream.next_out - compressed) < 0)
die(_("unable to write loose object file"));
stream.next_out = compressed;
stream.avail_out = sizeof(compressed);
} while (ret == Z_OK);
if (ret != Z_STREAM_END)
die(_("unable to deflate new object %s (%d)"), oid_to_hex(oid),
ret);
ret = git_deflate_end_gently(&stream);
if (ret != Z_OK)
die(_("deflateEnd on object %s failed (%d)"), oid_to_hex(oid),
ret);
the_hash_algo->final_fn(parano_oid.hash, &c);
if (!oideq(oid, &parano_oid))
die(_("confused by unstable object source data for %s"),
oid_to_hex(oid));
close_loose_object(fd);
if (mtime) {
struct utimbuf utb;
utb.actime = mtime;
utb.modtime = mtime;
if (utime(tmp_file.buf, &utb) < 0)
warning_errno(_("failed utime() on %s"), tmp_file.buf);
}
return finalize_object_file(tmp_file.buf, filename.buf);
}
static int freshen_loose_object(const struct object_id *oid)
{
return check_and_freshen(oid, 1);
}
static int freshen_packed_object(const struct object_id *oid)
{
struct pack_entry e;
if (!find_pack_entry(the_repository, oid, &e))
return 0;
if (e.p->freshened)
return 1;
if (!freshen_file(e.p->pack_name))
return 0;
e.p->freshened = 1;
return 1;
}
int write_object_file(const void *buf, unsigned long len, const char *type,
struct object_id *oid)
{
char hdr[MAX_HEADER_LEN];
int hdrlen = sizeof(hdr);
/* Normally if we have it in the pack then we do not bother writing
* it out into .git/objects/??/?{38} file.
*/
write_object_file_prepare(the_hash_algo, buf, len, type, oid, hdr,
&hdrlen);
if (freshen_packed_object(oid) || freshen_loose_object(oid))
return 0;
return write_loose_object(oid, hdr, hdrlen, buf, len, 0);
}
int hash_object_file_literally(const void *buf, unsigned long len,
const char *type, struct object_id *oid,
unsigned flags)
{
char *header;
int hdrlen, status = 0;
/* type string, SP, %lu of the length plus NUL must fit this */
hdrlen = strlen(type) + MAX_HEADER_LEN;
header = xmalloc(hdrlen);
write_object_file_prepare(the_hash_algo, buf, len, type, oid, header,
&hdrlen);
if (!(flags & HASH_WRITE_OBJECT))
goto cleanup;
if (freshen_packed_object(oid) || freshen_loose_object(oid))
goto cleanup;
status = write_loose_object(oid, header, hdrlen, buf, len, 0);
cleanup:
free(header);
return status;
}
int force_object_loose(const struct object_id *oid, time_t mtime)
{
void *buf;
unsigned long len;
enum object_type type;
char hdr[MAX_HEADER_LEN];
int hdrlen;
int ret;
if (has_loose_object(oid))
return 0;
buf = read_object(the_repository, oid, &type, &len);
if (!buf)
return error(_("cannot read object for %s"), oid_to_hex(oid));
hdrlen = xsnprintf(hdr, sizeof(hdr), "%s %"PRIuMAX , type_name(type), (uintmax_t)len) + 1;
ret = write_loose_object(oid, hdr, hdrlen, buf, len, mtime);
free(buf);
return ret;
}
int has_object(struct repository *r, const struct object_id *oid,
unsigned flags)
{
int quick = !(flags & HAS_OBJECT_RECHECK_PACKED);
unsigned object_info_flags = OBJECT_INFO_SKIP_FETCH_OBJECT |
(quick ? OBJECT_INFO_QUICK : 0);
if (!startup_info->have_repository)
return 0;
return oid_object_info_extended(r, oid, NULL, object_info_flags) >= 0;
}
int repo_has_object_file_with_flags(struct repository *r,
const struct object_id *oid, int flags)
{
if (!startup_info->have_repository)
return 0;
return oid_object_info_extended(r, oid, NULL, flags) >= 0;
}
int repo_has_object_file(struct repository *r,
const struct object_id *oid)
{
return repo_has_object_file_with_flags(r, oid, 0);
}
static void check_tree(const void *buf, size_t size)
{
struct tree_desc desc;
struct name_entry entry;
init_tree_desc(&desc, buf, size);
while (tree_entry(&desc, &entry))
/* do nothing
* tree_entry() will die() on malformed entries */
;
}
static void check_commit(const void *buf, size_t size)
{
struct commit c;
memset(&c, 0, sizeof(c));
if (parse_commit_buffer(the_repository, &c, buf, size, 0))
die(_("corrupt commit"));
}
static void check_tag(const void *buf, size_t size)
{
struct tag t;
memset(&t, 0, sizeof(t));
if (parse_tag_buffer(the_repository, &t, buf, size))
die(_("corrupt tag"));
}
static int index_mem(struct index_state *istate,
struct object_id *oid, void *buf, size_t size,
enum object_type type,
const char *path, unsigned flags)
{
int ret, re_allocated = 0;
int write_object = flags & HASH_WRITE_OBJECT;
if (!type)
type = OBJ_BLOB;
/*
* Convert blobs to git internal format
*/
if ((type == OBJ_BLOB) && path) {
struct strbuf nbuf = STRBUF_INIT;
if (convert_to_git(istate, path, buf, size, &nbuf,
get_conv_flags(flags))) {
buf = strbuf_detach(&nbuf, &size);
re_allocated = 1;
}
}
if (flags & HASH_FORMAT_CHECK) {
if (type == OBJ_TREE)
check_tree(buf, size);
if (type == OBJ_COMMIT)
check_commit(buf, size);
if (type == OBJ_TAG)
check_tag(buf, size);
}
if (write_object)
ret = write_object_file(buf, size, type_name(type), oid);
else
ret = hash_object_file(the_hash_algo, buf, size,
type_name(type), oid);
if (re_allocated)
free(buf);
return ret;
}
static int index_stream_convert_blob(struct index_state *istate,
struct object_id *oid,
int fd,
const char *path,
unsigned flags)
{
int ret;
const int write_object = flags & HASH_WRITE_OBJECT;
struct strbuf sbuf = STRBUF_INIT;
assert(path);
assert(would_convert_to_git_filter_fd(istate, path));
convert_to_git_filter_fd(istate, path, fd, &sbuf,
get_conv_flags(flags));
if (write_object)
ret = write_object_file(sbuf.buf, sbuf.len, type_name(OBJ_BLOB),
oid);
else
ret = hash_object_file(the_hash_algo, sbuf.buf, sbuf.len,
type_name(OBJ_BLOB), oid);
strbuf_release(&sbuf);
return ret;
}
static int index_pipe(struct index_state *istate, struct object_id *oid,
int fd, enum object_type type,
const char *path, unsigned flags)
{
struct strbuf sbuf = STRBUF_INIT;
int ret;
if (strbuf_read(&sbuf, fd, 4096) >= 0)
ret = index_mem(istate, oid, sbuf.buf, sbuf.len, type, path, flags);
else
ret = -1;
strbuf_release(&sbuf);
return ret;
}
#define SMALL_FILE_SIZE (32*1024)
static int index_core(struct index_state *istate,
struct object_id *oid, int fd, size_t size,
enum object_type type, const char *path,
unsigned flags)
{
int ret;
if (!size) {
ret = index_mem(istate, oid, "", size, type, path, flags);
} else if (size <= SMALL_FILE_SIZE) {
char *buf = xmalloc(size);
ssize_t read_result = read_in_full(fd, buf, size);
if (read_result < 0)
ret = error_errno(_("read error while indexing %s"),
path ? path : "<unknown>");
else if (read_result != size)
ret = error(_("short read while indexing %s"),
path ? path : "<unknown>");
else
ret = index_mem(istate, oid, buf, size, type, path, flags);
free(buf);
} else {
void *buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
ret = index_mem(istate, oid, buf, size, type, path, flags);
munmap(buf, size);
}
return ret;
}
/*
* This creates one packfile per large blob unless bulk-checkin
* machinery is "plugged".
*
* This also bypasses the usual "convert-to-git" dance, and that is on
* purpose. We could write a streaming version of the converting
* functions and insert that before feeding the data to fast-import
* (or equivalent in-core API described above). However, that is
* somewhat complicated, as we do not know the size of the filter
* result, which we need to know beforehand when writing a git object.
* Since the primary motivation for trying to stream from the working
* tree file and to avoid mmaping it in core is to deal with large
* binary blobs, they generally do not want to get any conversion, and
* callers should avoid this code path when filters are requested.
*/
static int index_stream(struct object_id *oid, int fd, size_t size,
enum object_type type, const char *path,
unsigned flags)
{
return index_bulk_checkin(oid, fd, size, type, path, flags);
}
int index_fd(struct index_state *istate, struct object_id *oid,
int fd, struct stat *st,
enum object_type type, const char *path, unsigned flags)
{
int ret;
/*
* Call xsize_t() only when needed to avoid potentially unnecessary
* die() for large files.
*/
if (type == OBJ_BLOB && path && would_convert_to_git_filter_fd(istate, path))
ret = index_stream_convert_blob(istate, oid, fd, path, flags);
else if (!S_ISREG(st->st_mode))
ret = index_pipe(istate, oid, fd, type, path, flags);
else if (st->st_size <= big_file_threshold || type != OBJ_BLOB ||
(path && would_convert_to_git(istate, path)))
ret = index_core(istate, oid, fd, xsize_t(st->st_size),
type, path, flags);
else
ret = index_stream(oid, fd, xsize_t(st->st_size), type, path,
flags);
close(fd);
return ret;
}
int index_path(struct index_state *istate, struct object_id *oid,
const char *path, struct stat *st, unsigned flags)
{
int fd;
struct strbuf sb = STRBUF_INIT;
int rc = 0;
switch (st->st_mode & S_IFMT) {
case S_IFREG:
fd = open(path, O_RDONLY);
if (fd < 0)
return error_errno("open(\"%s\")", path);
if (index_fd(istate, oid, fd, st, OBJ_BLOB, path, flags) < 0)
return error(_("%s: failed to insert into database"),
path);
break;
case S_IFLNK:
if (strbuf_readlink(&sb, path, st->st_size))
return error_errno("readlink(\"%s\")", path);
if (!(flags & HASH_WRITE_OBJECT))
hash_object_file(the_hash_algo, sb.buf, sb.len,
blob_type, oid);
else if (write_object_file(sb.buf, sb.len, blob_type, oid))
rc = error(_("%s: failed to insert into database"), path);
strbuf_release(&sb);
break;
case S_IFDIR:
return resolve_gitlink_ref(path, "HEAD", oid);
default:
return error(_("%s: unsupported file type"), path);
}
return rc;
}
int read_pack_header(int fd, struct pack_header *header)
{
if (read_in_full(fd, header, sizeof(*header)) != sizeof(*header))
/* "eof before pack header was fully read" */
return PH_ERROR_EOF;
if (header->hdr_signature != htonl(PACK_SIGNATURE))
/* "protocol error (pack signature mismatch detected)" */
return PH_ERROR_PACK_SIGNATURE;
if (!pack_version_ok(header->hdr_version))
/* "protocol error (pack version unsupported)" */
return PH_ERROR_PROTOCOL;
return 0;
}
void assert_oid_type(const struct object_id *oid, enum object_type expect)
{
enum object_type type = oid_object_info(the_repository, oid, NULL);
if (type < 0)
die(_("%s is not a valid object"), oid_to_hex(oid));
if (type != expect)
die(_("%s is not a valid '%s' object"), oid_to_hex(oid),
type_name(expect));
}
int for_each_file_in_obj_subdir(unsigned int subdir_nr,
struct strbuf *path,
each_loose_object_fn obj_cb,
each_loose_cruft_fn cruft_cb,
each_loose_subdir_fn subdir_cb,
void *data)
{
size_t origlen, baselen;
DIR *dir;
struct dirent *de;
int r = 0;
struct object_id oid;
if (subdir_nr > 0xff)
BUG("invalid loose object subdirectory: %x", subdir_nr);
origlen = path->len;
strbuf_complete(path, '/');
strbuf_addf(path, "%02x", subdir_nr);
dir = opendir(path->buf);
if (!dir) {
if (errno != ENOENT)
r = error_errno(_("unable to open %s"), path->buf);
strbuf_setlen(path, origlen);
return r;
}
oid.hash[0] = subdir_nr;
strbuf_addch(path, '/');
baselen = path->len;
while ((de = readdir(dir))) {
size_t namelen;
if (is_dot_or_dotdot(de->d_name))
continue;
namelen = strlen(de->d_name);
strbuf_setlen(path, baselen);
strbuf_add(path, de->d_name, namelen);
if (namelen == the_hash_algo->hexsz - 2 &&
!hex_to_bytes(oid.hash + 1, de->d_name,
the_hash_algo->rawsz - 1)) {
if (obj_cb) {
r = obj_cb(&oid, path->buf, data);
if (r)
break;
}
continue;
}
if (cruft_cb) {
r = cruft_cb(de->d_name, path->buf, data);
if (r)
break;
}
}
closedir(dir);
strbuf_setlen(path, baselen - 1);
if (!r && subdir_cb)
r = subdir_cb(subdir_nr, path->buf, data);
strbuf_setlen(path, origlen);
return r;
}
int for_each_loose_file_in_objdir_buf(struct strbuf *path,
each_loose_object_fn obj_cb,
each_loose_cruft_fn cruft_cb,
each_loose_subdir_fn subdir_cb,
void *data)
{
int r = 0;
int i;
for (i = 0; i < 256; i++) {
r = for_each_file_in_obj_subdir(i, path, obj_cb, cruft_cb,
subdir_cb, data);
if (r)
break;
}
return r;
}
int for_each_loose_file_in_objdir(const char *path,
each_loose_object_fn obj_cb,
each_loose_cruft_fn cruft_cb,
each_loose_subdir_fn subdir_cb,
void *data)
{
struct strbuf buf = STRBUF_INIT;
int r;
strbuf_addstr(&buf, path);
r = for_each_loose_file_in_objdir_buf(&buf, obj_cb, cruft_cb,
subdir_cb, data);
strbuf_release(&buf);
return r;
}
int for_each_loose_object(each_loose_object_fn cb, void *data,
enum for_each_object_flags flags)
{
struct object_directory *odb;
prepare_alt_odb(the_repository);
for (odb = the_repository->objects->odb; odb; odb = odb->next) {
int r = for_each_loose_file_in_objdir(odb->path, cb, NULL,
NULL, data);
if (r)
return r;
if (flags & FOR_EACH_OBJECT_LOCAL_ONLY)
break;
}
return 0;
}
static int append_loose_object(const struct object_id *oid, const char *path,
void *data)
{
oid_array_append(data, oid);
return 0;
}
struct oid_array *odb_loose_cache(struct object_directory *odb,
const struct object_id *oid)
{
int subdir_nr = oid->hash[0];
struct strbuf buf = STRBUF_INIT;
if (subdir_nr < 0 ||
subdir_nr >= ARRAY_SIZE(odb->loose_objects_subdir_seen))
BUG("subdir_nr out of range");
if (odb->loose_objects_subdir_seen[subdir_nr])
return &odb->loose_objects_cache[subdir_nr];
strbuf_addstr(&buf, odb->path);
for_each_file_in_obj_subdir(subdir_nr, &buf,
append_loose_object,
NULL, NULL,
&odb->loose_objects_cache[subdir_nr]);
odb->loose_objects_subdir_seen[subdir_nr] = 1;
strbuf_release(&buf);
return &odb->loose_objects_cache[subdir_nr];
}
void odb_clear_loose_cache(struct object_directory *odb)
{
int i;
for (i = 0; i < ARRAY_SIZE(odb->loose_objects_cache); i++)
oid_array_clear(&odb->loose_objects_cache[i]);
memset(&odb->loose_objects_subdir_seen, 0,
sizeof(odb->loose_objects_subdir_seen));
}
static int check_stream_oid(git_zstream *stream,
const char *hdr,
unsigned long size,
const char *path,
const struct object_id *expected_oid)
{
git_hash_ctx c;
struct object_id real_oid;
unsigned char buf[4096];
unsigned long total_read;
int status = Z_OK;
the_hash_algo->init_fn(&c);
the_hash_algo->update_fn(&c, hdr, stream->total_out);
/*
* We already read some bytes into hdr, but the ones up to the NUL
* do not count against the object's content size.
*/
total_read = stream->total_out - strlen(hdr) - 1;
/*
* This size comparison must be "<=" to read the final zlib packets;
* see the comment in unpack_loose_rest for details.
*/
while (total_read <= size &&
(status == Z_OK ||
(status == Z_BUF_ERROR && !stream->avail_out))) {
stream->next_out = buf;
stream->avail_out = sizeof(buf);
if (size - total_read < stream->avail_out)
stream->avail_out = size - total_read;
status = git_inflate(stream, Z_FINISH);
the_hash_algo->update_fn(&c, buf, stream->next_out - buf);
total_read += stream->next_out - buf;
}
git_inflate_end(stream);
if (status != Z_STREAM_END) {
error(_("corrupt loose object '%s'"), oid_to_hex(expected_oid));
return -1;
}
if (stream->avail_in) {
error(_("garbage at end of loose object '%s'"),
oid_to_hex(expected_oid));
return -1;
}
the_hash_algo->final_fn(real_oid.hash, &c);
if (!oideq(expected_oid, &real_oid)) {
error(_("hash mismatch for %s (expected %s)"), path,
oid_to_hex(expected_oid));
return -1;
}
return 0;
}
int read_loose_object(const char *path,
const struct object_id *expected_oid,
enum object_type *type,
unsigned long *size,
void **contents)
{
int ret = -1;
void *map = NULL;
unsigned long mapsize;
git_zstream stream;
char hdr[MAX_HEADER_LEN];
*contents = NULL;
map = map_loose_object_1(the_repository, path, NULL, &mapsize);
if (!map) {
error_errno(_("unable to mmap %s"), path);
goto out;
}
if (unpack_loose_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0) {
error(_("unable to unpack header of %s"), path);
goto out;
}
*type = parse_loose_header(hdr, size);
if (*type < 0) {
error(_("unable to parse header of %s"), path);
git_inflate_end(&stream);
goto out;
}
if (*type == OBJ_BLOB && *size > big_file_threshold) {
if (check_stream_oid(&stream, hdr, *size, path, expected_oid) < 0)
goto out;
} else {
*contents = unpack_loose_rest(&stream, hdr, *size, expected_oid);
if (!*contents) {
error(_("unable to unpack contents of %s"), path);
git_inflate_end(&stream);
goto out;
}
if (check_object_signature(the_repository, expected_oid,
*contents, *size,
type_name(*type))) {
error(_("hash mismatch for %s (expected %s)"), path,
oid_to_hex(expected_oid));
free(*contents);
goto out;
}
}
ret = 0; /* everything checks out */
out:
if (map)
munmap(map, mapsize);
return ret;
}
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