diff options
Diffstat (limited to 'builtin/gc.c')
-rw-r--r-- | builtin/gc.c | 95 |
1 files changed, 93 insertions, 2 deletions
diff --git a/builtin/gc.c b/builtin/gc.c index 6be6c8d65b..25f2237c08 100644 --- a/builtin/gc.c +++ b/builtin/gc.c @@ -14,6 +14,7 @@ #include "cache.h" #include "parse-options.h" #include "run-command.h" +#include "sigchain.h" #include "argv-array.h" #define FAILED_RUN "failed to run %s" @@ -35,6 +36,21 @@ static struct argv_array repack = ARGV_ARRAY_INIT; static struct argv_array prune = ARGV_ARRAY_INIT; static struct argv_array rerere = ARGV_ARRAY_INIT; +static char *pidfile; + +static void remove_pidfile(void) +{ + if (pidfile) + unlink(pidfile); +} + +static void remove_pidfile_on_signal(int signo) +{ + remove_pidfile(); + sigchain_pop(signo); + raise(signo); +} + static int gc_config(const char *var, const char *value, void *cb) { if (!strcmp(var, "gc.packrefs")) { @@ -167,19 +183,86 @@ static int need_to_gc(void) return 1; } +/* return NULL on success, else hostname running the gc */ +static const char *lock_repo_for_gc(int force, pid_t* ret_pid) +{ + static struct lock_file lock; + static char locking_host[128]; + char my_host[128]; + struct strbuf sb = STRBUF_INIT; + struct stat st; + uintmax_t pid; + FILE *fp; + int fd, should_exit; + + if (pidfile) + /* already locked */ + return NULL; + + if (gethostname(my_host, sizeof(my_host))) + strcpy(my_host, "unknown"); + + fd = hold_lock_file_for_update(&lock, git_path("gc.pid"), + LOCK_DIE_ON_ERROR); + if (!force) { + fp = fopen(git_path("gc.pid"), "r"); + memset(locking_host, 0, sizeof(locking_host)); + should_exit = + fp != NULL && + !fstat(fileno(fp), &st) && + /* + * 12 hour limit is very generous as gc should + * never take that long. On the other hand we + * don't really need a strict limit here, + * running gc --auto one day late is not a big + * problem. --force can be used in manual gc + * after the user verifies that no gc is + * running. + */ + time(NULL) - st.st_mtime <= 12 * 3600 && + fscanf(fp, "%"PRIuMAX" %127c", &pid, locking_host) == 2 && + /* be gentle to concurrent "gc" on remote hosts */ + (strcmp(locking_host, my_host) || !kill(pid, 0) || errno == EPERM); + if (fp != NULL) + fclose(fp); + if (should_exit) { + if (fd >= 0) + rollback_lock_file(&lock); + *ret_pid = pid; + return locking_host; + } + } + + strbuf_addf(&sb, "%"PRIuMAX" %s", + (uintmax_t) getpid(), my_host); + write_in_full(fd, sb.buf, sb.len); + strbuf_release(&sb); + commit_lock_file(&lock); + + pidfile = git_pathdup("gc.pid"); + sigchain_push_common(remove_pidfile_on_signal); + atexit(remove_pidfile); + + return NULL; +} + int cmd_gc(int argc, const char **argv, const char *prefix) { int aggressive = 0; int auto_gc = 0; int quiet = 0; + int force = 0; + const char *name; + pid_t pid; struct option builtin_gc_options[] = { OPT__QUIET(&quiet, N_("suppress progress reporting")), { OPTION_STRING, 0, "prune", &prune_expire, N_("date"), N_("prune unreferenced objects"), PARSE_OPT_OPTARG, NULL, (intptr_t)prune_expire }, - OPT_BOOLEAN(0, "aggressive", &aggressive, N_("be more thorough (increased runtime)")), - OPT_BOOLEAN(0, "auto", &auto_gc, N_("enable auto-gc mode")), + OPT_BOOL(0, "aggressive", &aggressive, N_("be more thorough (increased runtime)")), + OPT_BOOL(0, "auto", &auto_gc, N_("enable auto-gc mode")), + OPT_BOOL(0, "force", &force, N_("force running gc even if there may be another gc running")), OPT_END() }; @@ -225,6 +308,14 @@ int cmd_gc(int argc, const char **argv, const char *prefix) } else add_repack_all_option(); + name = lock_repo_for_gc(force, &pid); + if (name) { + if (auto_gc) + return 0; /* be quiet on --auto */ + die(_("gc is already running on machine '%s' pid %"PRIuMAX" (use --force if not)"), + name, (uintmax_t)pid); + } + if (pack_refs && run_command_v_opt(pack_refs_cmd.argv, RUN_GIT_CMD)) return error(FAILED_RUN, pack_refs_cmd.argv[0]); |