Update draft release notes for 1.5.5
[gitweb.git] / builtin-gc.c
index 939748261041049f31d62935ec08f062bdfa6e79..8cef36f6a4445b163b299f282785f66af9662cb8 100644 (file)
 
 #include "builtin.h"
 #include "cache.h"
+#include "parse-options.h"
 #include "run-command.h"
 
 #define FAILED_RUN "failed to run %s"
 
-static const char builtin_gc_usage[] = "git-gc [--prune] [--aggressive]";
+static const char * const builtin_gc_usage[] = {
+       "git-gc [options]",
+       NULL
+};
 
 static int pack_refs = 1;
 static int aggressive_window = -1;
+static int gc_auto_threshold = 6700;
+static int gc_auto_pack_limit = 50;
+static char *prune_expire = "2.weeks.ago";
 
 #define MAX_ADD 10
 static const char *argv_pack_refs[] = {"pack-refs", "--all", "--prune", NULL};
 static const char *argv_reflog[] = {"reflog", "expire", "--all", NULL};
-static const char *argv_repack[MAX_ADD] = {"repack", "-a", "-d", "-l", NULL};
-static const char *argv_prune[] = {"prune", NULL};
+static const char *argv_repack[MAX_ADD] = {"repack", "-d", "-l", NULL};
+static const char *argv_prune[] = {"prune", "--expire", NULL, NULL};
 static const char *argv_rerere[] = {"rerere", "gc", NULL};
 
 static int gc_config(const char *var, const char *value)
 {
        if (!strcmp(var, "gc.packrefs")) {
-               if (!strcmp(value, "notbare"))
+               if (value && !strcmp(value, "notbare"))
                        pack_refs = -1;
                else
                        pack_refs = git_config_bool(var, value);
@@ -41,6 +48,25 @@ static int gc_config(const char *var, const char *value)
                aggressive_window = git_config_int(var, value);
                return 0;
        }
+       if (!strcmp(var, "gc.auto")) {
+               gc_auto_threshold = git_config_int(var, value);
+               return 0;
+       }
+       if (!strcmp(var, "gc.autopacklimit")) {
+               gc_auto_pack_limit = git_config_int(var, value);
+               return 0;
+       }
+       if (!strcmp(var, "gc.pruneexpire")) {
+               if (!value)
+                       return config_error_nonbool(var);
+               if (strcmp(value, "now")) {
+                       unsigned long now = approxidate("now");
+                       if (approxidate(value) >= now)
+                               return error("Invalid %s: '%s'", var, value);
+               }
+               prune_expire = xstrdup(value);
+               return 0;
+       }
        return git_default_config(var, value);
 }
 
@@ -57,36 +83,159 @@ static void append_option(const char **cmd, const char *opt, int max_length)
        cmd[i] = NULL;
 }
 
+static int too_many_loose_objects(void)
+{
+       /*
+        * Quickly check if a "gc" is needed, by estimating how
+        * many loose objects there are.  Because SHA-1 is evenly
+        * distributed, we can check only one and get a reasonable
+        * estimate.
+        */
+       char path[PATH_MAX];
+       const char *objdir = get_object_directory();
+       DIR *dir;
+       struct dirent *ent;
+       int auto_threshold;
+       int num_loose = 0;
+       int needed = 0;
+
+       if (gc_auto_threshold <= 0)
+               return 0;
+
+       if (sizeof(path) <= snprintf(path, sizeof(path), "%s/17", objdir)) {
+               warning("insanely long object directory %.*s", 50, objdir);
+               return 0;
+       }
+       dir = opendir(path);
+       if (!dir)
+               return 0;
+
+       auto_threshold = (gc_auto_threshold + 255) / 256;
+       while ((ent = readdir(dir)) != NULL) {
+               if (strspn(ent->d_name, "0123456789abcdef") != 38 ||
+                   ent->d_name[38] != '\0')
+                       continue;
+               if (++num_loose > auto_threshold) {
+                       needed = 1;
+                       break;
+               }
+       }
+       closedir(dir);
+       return needed;
+}
+
+static int too_many_packs(void)
+{
+       struct packed_git *p;
+       int cnt;
+
+       if (gc_auto_pack_limit <= 0)
+               return 0;
+
+       prepare_packed_git();
+       for (cnt = 0, p = packed_git; p; p = p->next) {
+               char path[PATH_MAX];
+               size_t len;
+               int keep;
+
+               if (!p->pack_local)
+                       continue;
+               len = strlen(p->pack_name);
+               if (PATH_MAX <= len + 1)
+                       continue; /* oops, give up */
+               memcpy(path, p->pack_name, len-5);
+               memcpy(path + len - 5, ".keep", 6);
+               keep = access(p->pack_name, F_OK) && (errno == ENOENT);
+               if (keep)
+                       continue;
+               /*
+                * Perhaps check the size of the pack and count only
+                * very small ones here?
+                */
+               cnt++;
+       }
+       return gc_auto_pack_limit <= cnt;
+}
+
+static int need_to_gc(void)
+{
+       /*
+        * Setting gc.auto to 0 or negative can disable the
+        * automatic gc.
+        */
+       if (gc_auto_threshold <= 0)
+               return 0;
+
+       /*
+        * If there are too many loose objects, but not too many
+        * packs, we run "repack -d -l".  If there are too many packs,
+        * we run "repack -A -d -l".  Otherwise we tell the caller
+        * there is no need.
+        */
+       if (too_many_packs())
+               append_option(argv_repack, "-A", MAX_ADD);
+       else if (!too_many_loose_objects())
+               return 0;
+       return 1;
+}
+
 int cmd_gc(int argc, const char **argv, const char *prefix)
 {
-       int i;
        int prune = 0;
+       int aggressive = 0;
+       int auto_gc = 0;
+       int quiet = 0;
        char buf[80];
 
+       struct option builtin_gc_options[] = {
+               OPT_BOOLEAN(0, "prune", &prune, "prune unreferenced objects"),
+               OPT_BOOLEAN(0, "aggressive", &aggressive, "be more thorough (increased runtime)"),
+               OPT_BOOLEAN(0, "auto", &auto_gc, "enable auto-gc mode"),
+               OPT_BOOLEAN('q', "quiet", &quiet, "suppress progress reports"),
+               OPT_END()
+       };
+
        git_config(gc_config);
 
        if (pack_refs < 0)
                pack_refs = !is_bare_repository();
 
-       for (i = 1; i < argc; i++) {
-               const char *arg = argv[i];
-               if (!strcmp(arg, "--prune")) {
-                       prune = 1;
-                       continue;
-               }
-               if (!strcmp(arg, "--aggressive")) {
-                       append_option(argv_repack, "-f", MAX_ADD);
-                       if (aggressive_window > 0) {
-                               sprintf(buf, "--window=%d", aggressive_window);
-                               append_option(argv_repack, buf, MAX_ADD);
-                       }
-                       continue;
+       argc = parse_options(argc, argv, builtin_gc_options, builtin_gc_usage, 0);
+       if (argc > 0)
+               usage_with_options(builtin_gc_usage, builtin_gc_options);
+
+       if (aggressive) {
+               append_option(argv_repack, "-f", MAX_ADD);
+               if (aggressive_window > 0) {
+                       sprintf(buf, "--window=%d", aggressive_window);
+                       append_option(argv_repack, buf, MAX_ADD);
                }
-               /* perhaps other parameters later... */
-               break;
        }
-       if (i != argc)
-               usage(builtin_gc_usage);
+       if (quiet)
+               append_option(argv_repack, "-q", MAX_ADD);
+
+       if (auto_gc) {
+               /*
+                * Auto-gc should be least intrusive as possible.
+                */
+               prune = 0;
+               if (!need_to_gc())
+                       return 0;
+               fprintf(stderr, "Auto packing your repository for optimum "
+                       "performance. You may also\n"
+                       "run \"git gc\" manually. See "
+                       "\"git help gc\" for more information.\n");
+       } else {
+               /*
+                * Use safer (for shared repos) "-A" option to
+                * repack when not pruning. Auto-gc makes its
+                * own decision.
+                */
+               if (prune)
+                       append_option(argv_repack, "-a", MAX_ADD);
+               else
+                       append_option(argv_repack, "-A", MAX_ADD);
+       }
 
        if (pack_refs && run_command_v_opt(argv_pack_refs, RUN_GIT_CMD))
                return error(FAILED_RUN, argv_pack_refs[0]);
@@ -97,11 +246,16 @@ int cmd_gc(int argc, const char **argv, const char *prefix)
        if (run_command_v_opt(argv_repack, RUN_GIT_CMD))
                return error(FAILED_RUN, argv_repack[0]);
 
-       if (prune && run_command_v_opt(argv_prune, RUN_GIT_CMD))
+       argv_prune[2] = prune_expire;
+       if (run_command_v_opt(argv_prune, RUN_GIT_CMD))
                return error(FAILED_RUN, argv_prune[0]);
 
        if (run_command_v_opt(argv_rerere, RUN_GIT_CMD))
                return error(FAILED_RUN, argv_rerere[0]);
 
+       if (auto_gc && too_many_loose_objects())
+               warning("There are too many unreachable loose objects; "
+                       "run 'git prune' to remove them.");
+
        return 0;
 }