const unsigned char null_sha1[20];
+static const char *no_log_pack_access = "no_log_pack_access";
+static const char *log_pack_access;
+
/*
* This is meant to hold a *small* number of objects that you would
* want read_sha1_file() to be able to return, but yet you do not want
}
}
-static int unuse_one_window(struct packed_git *current, int keep_fd)
+static int unuse_one_window(struct packed_git *current)
{
struct packed_git *p, *lru_p = NULL;
struct pack_window *lru_w = NULL, *lru_l = NULL;
pack_mapped -= lru_w->len;
if (lru_l)
lru_l->next = lru_w->next;
- else {
+ else
lru_p->windows = lru_w->next;
- if (!lru_p->windows && lru_p->pack_fd != -1
- && lru_p->pack_fd != keep_fd) {
- close(lru_p->pack_fd);
- pack_open_fds--;
- lru_p->pack_fd = -1;
- }
- }
free(lru_w);
pack_open_windows--;
return 1;
return 0;
}
-void release_pack_memory(size_t need, int fd)
+void release_pack_memory(size_t need)
{
size_t cur = pack_mapped;
- while (need >= (cur - pack_mapped) && unuse_one_window(NULL, fd))
+ while (need >= (cur - pack_mapped) && unuse_one_window(NULL))
; /* nothing */
}
if (ret == MAP_FAILED) {
if (!length)
return NULL;
- release_pack_memory(length, fd);
+ release_pack_memory(length);
ret = mmap(start, length, prot, flags, fd, offset);
if (ret == MAP_FAILED)
die_errno("Out of memory? mmap failed");
}
}
+/*
+ * The LRU pack is the one with the oldest MRU window, preferring packs
+ * with no used windows, or the oldest mtime if it has no windows allocated.
+ */
+static void find_lru_pack(struct packed_git *p, struct packed_git **lru_p, struct pack_window **mru_w, int *accept_windows_inuse)
+{
+ struct pack_window *w, *this_mru_w;
+ int has_windows_inuse = 0;
+
+ /*
+ * Reject this pack if it has windows and the previously selected
+ * one does not. If this pack does not have windows, reject
+ * it if the pack file is newer than the previously selected one.
+ */
+ if (*lru_p && !*mru_w && (p->windows || p->mtime > (*lru_p)->mtime))
+ return;
+
+ for (w = this_mru_w = p->windows; w; w = w->next) {
+ /*
+ * Reject this pack if any of its windows are in use,
+ * but the previously selected pack did not have any
+ * inuse windows. Otherwise, record that this pack
+ * has windows in use.
+ */
+ if (w->inuse_cnt) {
+ if (*accept_windows_inuse)
+ has_windows_inuse = 1;
+ else
+ return;
+ }
+
+ if (w->last_used > this_mru_w->last_used)
+ this_mru_w = w;
+
+ /*
+ * Reject this pack if it has windows that have been
+ * used more recently than the previously selected pack.
+ * If the previously selected pack had windows inuse and
+ * we have not encountered a window in this pack that is
+ * inuse, skip this check since we prefer a pack with no
+ * inuse windows to one that has inuse windows.
+ */
+ if (*mru_w && *accept_windows_inuse == has_windows_inuse &&
+ this_mru_w->last_used > (*mru_w)->last_used)
+ return;
+ }
+
+ /*
+ * Select this pack.
+ */
+ *mru_w = this_mru_w;
+ *lru_p = p;
+ *accept_windows_inuse = has_windows_inuse;
+}
+
+static int close_one_pack(void)
+{
+ struct packed_git *p, *lru_p = NULL;
+ struct pack_window *mru_w = NULL;
+ int accept_windows_inuse = 1;
+
+ for (p = packed_git; p; p = p->next) {
+ if (p->pack_fd == -1)
+ continue;
+ find_lru_pack(p, &lru_p, &mru_w, &accept_windows_inuse);
+ }
+
+ if (lru_p) {
+ close(lru_p->pack_fd);
+ pack_open_fds--;
+ lru_p->pack_fd = -1;
+ return 1;
+ }
+
+ return 0;
+}
+
void unuse_pack(struct pack_window **w_cursor)
{
struct pack_window *w = *w_cursor;
pack_max_fds = 1;
}
- while (pack_max_fds <= pack_open_fds && unuse_one_window(NULL, -1))
+ while (pack_max_fds <= pack_open_fds && close_one_pack())
; /* nothing */
p->pack_fd = git_open_noatime(p->pack_name);
win->len = (size_t)len;
pack_mapped += win->len;
while (packed_git_limit < pack_mapped
- && unuse_one_window(p, p->pack_fd))
+ && unuse_one_window(p))
; /* nothing */
win->base = xmmap(NULL, win->len,
PROT_READ, MAP_PRIVATE,
static void try_to_free_pack_memory(size_t size)
{
- release_pack_memory(size, -1);
+ release_pack_memory(size);
}
struct packed_git *add_packed_git(const char *path, int path_len, int local)
}
static int packed_object_info(struct packed_git *p, off_t obj_offset,
- enum object_type *typep, unsigned long *sizep,
- unsigned long *disk_sizep)
+ struct object_info *oi)
{
struct pack_window *w_curs = NULL;
unsigned long size;
*/
type = unpack_object_header(p, &w_curs, &curpos, &size);
- if (sizep) {
+ if (oi->sizep) {
if (type == OBJ_OFS_DELTA || type == OBJ_REF_DELTA) {
off_t tmp_pos = curpos;
off_t base_offset = get_delta_base(p, &w_curs, &tmp_pos,
type = OBJ_BAD;
goto out;
}
- *sizep = get_size_from_delta(p, &w_curs, tmp_pos);
- if (*sizep == 0) {
+ *oi->sizep = get_size_from_delta(p, &w_curs, tmp_pos);
+ if (*oi->sizep == 0) {
type = OBJ_BAD;
goto out;
}
} else {
- *sizep = size;
+ *oi->sizep = size;
}
}
- if (disk_sizep) {
+ if (oi->disk_sizep) {
struct revindex_entry *revidx = find_pack_revindex(p, obj_offset);
- *disk_sizep = revidx[1].offset - obj_offset;
+ *oi->disk_sizep = revidx[1].offset - obj_offset;
}
- if (typep) {
- *typep = packed_to_object_type(p, obj_offset, type, &w_curs, curpos);
- if (*typep < 0) {
+ if (oi->typep) {
+ *oi->typep = packed_to_object_type(p, obj_offset, type, &w_curs, curpos);
+ if (*oi->typep < 0) {
type = OBJ_BAD;
goto out;
}
{
static FILE *log_file;
+ if (!log_pack_access)
+ log_pack_access = getenv("GIT_TRACE_PACK_ACCESS");
+ if (!log_pack_access)
+ log_pack_access = no_log_pack_access;
+ if (log_pack_access == no_log_pack_access)
+ return;
+
if (!log_file) {
log_file = fopen(log_pack_access, "w");
if (!log_file) {
error("cannot open pack access log '%s' for writing: %s",
log_pack_access, strerror(errno));
- log_pack_access = NULL;
+ log_pack_access = no_log_pack_access;
return;
}
}
int delta_stack_nr = 0, delta_stack_alloc = UNPACK_ENTRY_STACK_PREALLOC;
int base_from_cache = 0;
- if (log_pack_access)
+ if (log_pack_access != no_log_pack_access)
write_pack_access_log(p, obj_offset);
/* PHASE 1: drill down to the innermost base object */
data = patch_delta(base, base_size,
delta_data, delta_size,
&size);
+
+ /*
+ * We could not apply the delta; warn the user, but keep going.
+ * Our failure will be noticed either in the next iteration of
+ * the loop, or if this is the final delta, in the caller when
+ * we return NULL. Those code paths will take care of making
+ * a more explicit warning and retrying with another copy of
+ * the object.
+ */
if (!data)
- die("failed to apply delta");
+ error("failed to apply delta");
- free (delta_data);
+ free(delta_data);
}
*final_type = type;
}
static int sha1_loose_object_info(const unsigned char *sha1,
- enum object_type *typep,
- unsigned long *sizep,
- unsigned long *disk_sizep)
+ struct object_info *oi)
{
int status;
unsigned long mapsize, size;
* If we don't care about type or size, then we don't
* need to look inside the object at all.
*/
- if (!typep && !sizep) {
- if (disk_sizep) {
+ if (!oi->typep && !oi->sizep) {
+ if (oi->disk_sizep) {
struct stat st;
if (stat_sha1_file(sha1, &st) < 0)
return -1;
- *disk_sizep = st.st_size;
+ *oi->disk_sizep = st.st_size;
}
return 0;
}
map = map_sha1_file(sha1, &mapsize);
if (!map)
- return error("unable to find %s", sha1_to_hex(sha1));
- if (disk_sizep)
- *disk_sizep = mapsize;
+ return -1;
+ if (oi->disk_sizep)
+ *oi->disk_sizep = mapsize;
if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
status = error("unable to unpack %s header",
sha1_to_hex(sha1));
else if ((status = parse_sha1_header(hdr, &size)) < 0)
status = error("unable to parse %s header", sha1_to_hex(sha1));
- else if (sizep)
- *sizep = size;
+ else if (oi->sizep)
+ *oi->sizep = size;
git_inflate_end(&stream);
munmap(map, mapsize);
- if (typep)
- *typep = status;
+ if (oi->typep)
+ *oi->typep = status;
return 0;
}
if (!find_pack_entry(sha1, &e)) {
/* Most likely it's a loose object. */
- if (!sha1_loose_object_info(sha1, oi->typep,
- oi->sizep, oi->disk_sizep)) {
+ if (!sha1_loose_object_info(sha1, oi)) {
oi->whence = OI_LOOSE;
return 0;
}
return -1;
}
- rtype = packed_object_info(e.p, e.offset, oi->typep, oi->sizep,
- oi->disk_sizep);
+ rtype = packed_object_info(e.p, e.offset, oi);
if (rtype < 0) {
mark_bad_packed_object(e.p, sha1);
return sha1_object_info_extended(sha1, oi);
int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
{
enum object_type type;
- struct object_info oi = {0};
+ struct object_info oi = {NULL};
oi.typep = &type;
oi.sizep = sizep;