diff options
Diffstat (limited to 'sha1_file.c')
-rw-r--r-- | sha1_file.c | 162 |
1 files changed, 109 insertions, 53 deletions
diff --git a/sha1_file.c b/sha1_file.c index d86a8db69a..e194f6a128 100644 --- a/sha1_file.c +++ b/sha1_file.c @@ -37,6 +37,41 @@ const unsigned char null_sha1[20]; static int git_open_noatime(const char *name, struct packed_git *p); +/* + * 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 + * to write them into the object store (e.g. a browse-only + * application). + */ +static struct cached_object { + unsigned char sha1[20]; + 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 unsigned char *sha1) +{ + int i; + struct cached_object *co = cached_objects; + + for (i = 0; i < cached_object_nr; i++, co++) { + if (!hashcmp(co->sha1, sha1)) + return co; + } + if (!hashcmp(sha1, empty_tree.sha1)) + return &empty_tree; + return NULL; +} + int safe_create_leading_directories(char *path) { char *pos = path + offset_1st_component(path); @@ -382,6 +417,8 @@ static unsigned int pack_used_ctr; static unsigned int pack_mmap_calls; static unsigned int peak_pack_open_windows; static unsigned int pack_open_windows; +static unsigned int pack_open_fds; +static unsigned int pack_max_fds; static size_t peak_pack_mapped; static size_t pack_mapped; struct packed_git *packed_git; @@ -559,8 +596,10 @@ static int unuse_one_window(struct packed_git *current, int keep_fd) lru_l->next = lru_w->next; else { lru_p->windows = lru_w->next; - if (!lru_p->windows && lru_p->pack_fd != keep_fd) { + 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; } } @@ -645,8 +684,10 @@ void free_pack_by_name(const char *pack_name) if (strcmp(pack_name, p->pack_name) == 0) { clear_delta_base_cache(); close_pack_windows(p); - if (p->pack_fd != -1) + if (p->pack_fd != -1) { close(p->pack_fd); + pack_open_fds--; + } close_pack_index(p); free(p->bad_object_sha1); *pp = p->next; @@ -672,9 +713,29 @@ static int open_packed_git_1(struct packed_git *p) if (!p->index_data && open_pack_index(p)) return error("packfile %s index unavailable", p->pack_name); + if (!pack_max_fds) { + struct rlimit lim; + unsigned int max_fds; + + if (getrlimit(RLIMIT_NOFILE, &lim)) + die_errno("cannot get RLIMIT_NOFILE"); + + max_fds = lim.rlim_cur; + + /* Save 3 for stdin/stdout/stderr, 22 for work */ + if (25 < max_fds) + pack_max_fds = max_fds - 25; + else + pack_max_fds = 1; + } + + while (pack_max_fds <= pack_open_fds && unuse_one_window(NULL, -1)) + ; /* nothing */ + p->pack_fd = git_open_noatime(p->pack_name, p); if (p->pack_fd < 0 || fstat(p->pack_fd, &st)) return -1; + pack_open_fds++; /* If we created the struct before we had the pack we lack size. */ if (!p->pack_size) { @@ -726,6 +787,7 @@ static int open_packed_git(struct packed_git *p) return 0; if (p->pack_fd != -1) { close(p->pack_fd); + pack_open_fds--; p->pack_fd = -1; } return -1; @@ -751,14 +813,13 @@ unsigned char *use_pack(struct packed_git *p, { struct pack_window *win = *w_cursor; - if (p->pack_fd == -1 && open_packed_git(p)) - die("packfile %s cannot be accessed", p->pack_name); - /* Since packfiles end in a hash of their content and it's * pointless to ask for an offset into the middle of that * hash, and the in_window function above wouldn't match * don't allow an offset too close to the end of the file. */ + if (!p->pack_size && p->pack_fd == -1 && open_packed_git(p)) + die("packfile %s cannot be accessed", p->pack_name); if (offset > (p->pack_size - 20)) die("offset beyond end of packfile (truncated pack?)"); @@ -772,6 +833,10 @@ unsigned char *use_pack(struct packed_git *p, if (!win) { size_t window_align = packed_git_window_size / 2; off_t len; + + if (p->pack_fd == -1 && open_packed_git(p)) + die("packfile %s cannot be accessed", p->pack_name); + win = xcalloc(1, sizeof(*win)); win->offset = (offset / window_align) * window_align; len = p->pack_size - win->offset; @@ -789,6 +854,12 @@ unsigned char *use_pack(struct packed_git *p, die("packfile %s cannot be mapped: %s", p->pack_name, strerror(errno)); + if (!win->offset && win->len == p->pack_size + && !p->do_not_close) { + close(p->pack_fd); + pack_open_fds--; + p->pack_fd = -1; + } pack_mmap_calls++; pack_open_windows++; if (pack_mapped > peak_pack_mapped) @@ -883,6 +954,9 @@ struct packed_git *parse_pack_index(unsigned char *sha1, const char *idx_path) void install_packed_git(struct packed_git *pack) { + if (pack->pack_fd != -1) + pack_open_fds++; + pack->next = packed_git; packed_git = pack; } @@ -900,8 +974,6 @@ static void prepare_packed_git_one(char *objdir, int local) sprintf(path, "%s/pack", objdir); len = strlen(path); dir = opendir(path); - while (!dir && errno == EMFILE && unuse_one_window(NULL, -1)) - dir = opendir(path); if (!dir) { if (errno != ENOENT) error("unable to open object pack directory: %s: %s", @@ -1057,14 +1129,6 @@ static int git_open_noatime(const char *name, struct packed_git *p) if (fd >= 0) return fd; - /* Might the failure be insufficient file descriptors? */ - if (errno == EMFILE) { - if (unuse_one_window(p, -1)) - continue; - else - return -1; - } - /* Might the failure be due to O_NOATIME? */ if (errno != ENOENT && sha1_file_open_flag) { sha1_file_open_flag = 0; @@ -1896,6 +1960,27 @@ off_t find_pack_entry_one(const unsigned char *sha1, return 0; } +static int is_pack_valid(struct packed_git *p) +{ + /* An already open pack is known to be valid. */ + if (p->pack_fd != -1) + return 1; + + /* If the pack has one window completely covering the + * file size, the pack is known to be valid even if + * the descriptor is not currently open. + */ + if (p->windows) { + struct pack_window *w = p->windows; + + if (!w->offset && w->len == p->pack_size) + return 1; + } + + /* Force the pack to open to prove its valid. */ + return !open_packed_git(p); +} + static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e) { static struct packed_git *last_found = (void *)1; @@ -1925,7 +2010,7 @@ static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e) * it may have been deleted since the index * was loaded! */ - if (p->pack_fd == -1 && open_packed_git(p)) { + if (!is_pack_valid(p)) { error("packfile %s cannot be accessed", p->pack_name); goto next; } @@ -1985,9 +2070,17 @@ static int sha1_loose_object_info(const unsigned char *sha1, unsigned long *size int sha1_object_info(const unsigned char *sha1, unsigned long *sizep) { + struct cached_object *co; struct pack_entry e; int status; + co = find_cached_object(sha1); + if (co) { + if (sizep) + *sizep = co->size; + return co->type; + } + if (!find_pack_entry(sha1, &e)) { /* Most likely it's a loose object. */ status = sha1_loose_object_info(sha1, sizep); @@ -2033,41 +2126,6 @@ static void *read_packed_sha1(const unsigned char *sha1, return data; } -/* - * 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 - * to write them into the object store (e.g. a browse-only - * application). - */ -static struct cached_object { - unsigned char sha1[20]; - 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, - OBJ_TREE, - "", - 0 -}; - -static struct cached_object *find_cached_object(const unsigned char *sha1) -{ - int i; - struct cached_object *co = cached_objects; - - for (i = 0; i < cached_object_nr; i++, co++) { - if (!hashcmp(co->sha1, sha1)) - return co; - } - if (!hashcmp(sha1, empty_tree.sha1)) - return &empty_tree; - return NULL; -} - int pretend_sha1_file(void *buf, unsigned long len, enum object_type type, unsigned char *sha1) { @@ -2351,8 +2409,6 @@ static int write_loose_object(const unsigned char *sha1, char *hdr, int hdrlen, filename = sha1_file_name(sha1); fd = create_tmpfile(tmpfile, sizeof(tmpfile), filename); - while (fd < 0 && errno == EMFILE && unuse_one_window(NULL, -1)) - fd = create_tmpfile(tmpfile, sizeof(tmpfile), filename); if (fd < 0) { if (errno == EACCES) return error("insufficient permission for adding an object to repository database %s\n", get_object_directory()); |