repack: fix trying to use preferred pack in alternates
[alt-git.git] / tmp-objdir.c
blob2a2012eb6d0d4b38c047b570ca06697ffead6dbd
1 #include "cache.h"
2 #include "tmp-objdir.h"
3 #include "chdir-notify.h"
4 #include "dir.h"
5 #include "sigchain.h"
6 #include "string-list.h"
7 #include "strbuf.h"
8 #include "strvec.h"
9 #include "quote.h"
10 #include "object-store.h"
12 struct tmp_objdir {
13 struct strbuf path;
14 struct strvec env;
15 struct object_directory *prev_odb;
16 int will_destroy;
20 * Allow only one tmp_objdir at a time in a running process, which simplifies
21 * our atexit cleanup routines. It's doubtful callers will ever need
22 * more than one, and we can expand later if so. You can have many such
23 * tmp_objdirs simultaneously in many processes, of course.
25 static struct tmp_objdir *the_tmp_objdir;
27 static void tmp_objdir_free(struct tmp_objdir *t)
29 strbuf_release(&t->path);
30 strvec_clear(&t->env);
31 free(t);
34 int tmp_objdir_destroy(struct tmp_objdir *t)
36 int err;
38 if (!t)
39 return 0;
41 if (t == the_tmp_objdir)
42 the_tmp_objdir = NULL;
44 if (t->prev_odb)
45 restore_primary_odb(t->prev_odb, t->path.buf);
47 err = remove_dir_recursively(&t->path, 0);
49 tmp_objdir_free(t);
51 return err;
54 static void remove_tmp_objdir(void)
56 tmp_objdir_destroy(the_tmp_objdir);
59 void tmp_objdir_discard_objects(struct tmp_objdir *t)
61 remove_dir_recursively(&t->path, REMOVE_DIR_KEEP_TOPLEVEL);
65 * These env_* functions are for setting up the child environment; the
66 * "replace" variant overrides the value of any existing variable with that
67 * "key". The "append" variant puts our new value at the end of a list,
68 * separated by PATH_SEP (which is what separate values in
69 * GIT_ALTERNATE_OBJECT_DIRECTORIES).
71 static void env_append(struct strvec *env, const char *key, const char *val)
73 struct strbuf quoted = STRBUF_INIT;
74 const char *old;
77 * Avoid quoting if it's not necessary, for maximum compatibility
78 * with older parsers which don't understand the quoting.
80 if (*val == '"' || strchr(val, PATH_SEP)) {
81 strbuf_addch(&quoted, '"');
82 quote_c_style(val, &quoted, NULL, 1);
83 strbuf_addch(&quoted, '"');
84 val = quoted.buf;
87 old = getenv(key);
88 if (!old)
89 strvec_pushf(env, "%s=%s", key, val);
90 else
91 strvec_pushf(env, "%s=%s%c%s", key, old, PATH_SEP, val);
93 strbuf_release(&quoted);
96 static void env_replace(struct strvec *env, const char *key, const char *val)
98 strvec_pushf(env, "%s=%s", key, val);
101 static int setup_tmp_objdir(const char *root)
103 char *path;
104 int ret = 0;
106 path = xstrfmt("%s/pack", root);
107 ret = mkdir(path, 0777);
108 free(path);
110 return ret;
113 struct tmp_objdir *tmp_objdir_create(const char *prefix)
115 static int installed_handlers;
116 struct tmp_objdir *t;
118 if (the_tmp_objdir)
119 BUG("only one tmp_objdir can be used at a time");
121 t = xcalloc(1, sizeof(*t));
122 strbuf_init(&t->path, 0);
123 strvec_init(&t->env);
126 * Use a string starting with tmp_ so that the builtin/prune.c code
127 * can recognize any stale objdirs left behind by a crash and delete
128 * them.
130 strbuf_addf(&t->path, "%s/tmp_objdir-%s-XXXXXX", get_object_directory(), prefix);
132 if (!mkdtemp(t->path.buf)) {
133 /* free, not destroy, as we never touched the filesystem */
134 tmp_objdir_free(t);
135 return NULL;
138 the_tmp_objdir = t;
139 if (!installed_handlers) {
140 atexit(remove_tmp_objdir);
141 installed_handlers++;
144 if (setup_tmp_objdir(t->path.buf)) {
145 tmp_objdir_destroy(t);
146 return NULL;
149 env_append(&t->env, ALTERNATE_DB_ENVIRONMENT,
150 absolute_path(get_object_directory()));
151 env_replace(&t->env, DB_ENVIRONMENT, absolute_path(t->path.buf));
152 env_replace(&t->env, GIT_QUARANTINE_ENVIRONMENT,
153 absolute_path(t->path.buf));
155 return t;
159 * Make sure we copy packfiles and their associated metafiles in the correct
160 * order. All of these ends_with checks are slightly expensive to do in
161 * the midst of a sorting routine, but in practice it shouldn't matter.
162 * We will have a relatively small number of packfiles to order, and loose
163 * objects exit early in the first line.
165 static int pack_copy_priority(const char *name)
167 if (!starts_with(name, "pack"))
168 return 0;
169 if (ends_with(name, ".keep"))
170 return 1;
171 if (ends_with(name, ".pack"))
172 return 2;
173 if (ends_with(name, ".rev"))
174 return 3;
175 if (ends_with(name, ".idx"))
176 return 4;
177 return 5;
180 static int pack_copy_cmp(const char *a, const char *b)
182 return pack_copy_priority(a) - pack_copy_priority(b);
185 static int read_dir_paths(struct string_list *out, const char *path)
187 DIR *dh;
188 struct dirent *de;
190 dh = opendir(path);
191 if (!dh)
192 return -1;
194 while ((de = readdir(dh)))
195 if (de->d_name[0] != '.')
196 string_list_append(out, de->d_name);
198 closedir(dh);
199 return 0;
202 static int migrate_paths(struct strbuf *src, struct strbuf *dst);
204 static int migrate_one(struct strbuf *src, struct strbuf *dst)
206 struct stat st;
208 if (stat(src->buf, &st) < 0)
209 return -1;
210 if (S_ISDIR(st.st_mode)) {
211 if (!mkdir(dst->buf, 0777)) {
212 if (adjust_shared_perm(dst->buf))
213 return -1;
214 } else if (errno != EEXIST)
215 return -1;
216 return migrate_paths(src, dst);
218 return finalize_object_file(src->buf, dst->buf);
221 static int migrate_paths(struct strbuf *src, struct strbuf *dst)
223 size_t src_len = src->len, dst_len = dst->len;
224 struct string_list paths = STRING_LIST_INIT_DUP;
225 int i;
226 int ret = 0;
228 if (read_dir_paths(&paths, src->buf) < 0)
229 return -1;
230 paths.cmp = pack_copy_cmp;
231 string_list_sort(&paths);
233 for (i = 0; i < paths.nr; i++) {
234 const char *name = paths.items[i].string;
236 strbuf_addf(src, "/%s", name);
237 strbuf_addf(dst, "/%s", name);
239 ret |= migrate_one(src, dst);
241 strbuf_setlen(src, src_len);
242 strbuf_setlen(dst, dst_len);
245 string_list_clear(&paths, 0);
246 return ret;
249 int tmp_objdir_migrate(struct tmp_objdir *t)
251 struct strbuf src = STRBUF_INIT, dst = STRBUF_INIT;
252 int ret;
254 if (!t)
255 return 0;
257 if (t->prev_odb) {
258 if (the_repository->objects->odb->will_destroy)
259 BUG("migrating an ODB that was marked for destruction");
260 restore_primary_odb(t->prev_odb, t->path.buf);
261 t->prev_odb = NULL;
264 strbuf_addbuf(&src, &t->path);
265 strbuf_addstr(&dst, get_object_directory());
267 ret = migrate_paths(&src, &dst);
269 strbuf_release(&src);
270 strbuf_release(&dst);
272 tmp_objdir_destroy(t);
273 return ret;
276 const char **tmp_objdir_env(const struct tmp_objdir *t)
278 if (!t)
279 return NULL;
280 return t->env.v;
283 void tmp_objdir_add_as_alternate(const struct tmp_objdir *t)
285 add_to_alternates_memory(t->path.buf);
288 void tmp_objdir_replace_primary_odb(struct tmp_objdir *t, int will_destroy)
290 if (t->prev_odb)
291 BUG("the primary object database is already replaced");
292 t->prev_odb = set_temporary_primary_odb(t->path.buf, will_destroy);
293 t->will_destroy = will_destroy;
296 struct tmp_objdir *tmp_objdir_unapply_primary_odb(void)
298 if (!the_tmp_objdir || !the_tmp_objdir->prev_odb)
299 return NULL;
301 restore_primary_odb(the_tmp_objdir->prev_odb, the_tmp_objdir->path.buf);
302 the_tmp_objdir->prev_odb = NULL;
303 return the_tmp_objdir;
306 void tmp_objdir_reapply_primary_odb(struct tmp_objdir *t, const char *old_cwd,
307 const char *new_cwd)
309 char *path;
311 path = reparent_relative_path(old_cwd, new_cwd, t->path.buf);
312 strbuf_reset(&t->path);
313 strbuf_addstr(&t->path, path);
314 free(path);
315 tmp_objdir_replace_primary_odb(t, t->will_destroy);