From a1bbc6c0176f1fa2d4aa571cc0183a1f0ff9b285 Mon Sep 17 00:00:00 2001 From: Stefan Beller Date: Sun, 15 Sep 2013 17:33:20 +0200 Subject: [PATCH] repack: rewrite the shell script in C The motivation of this patch is to get closer to a goal of being able to have a core subset of git functionality built in to git. That would mean * people on Windows could get a copy of at least the core parts of Git without having to install a Unix-style shell * people using git in on servers with chrooted environments do not need to worry about standard tools lacking for shell scripts. This patch is meant to be mostly a literal translation of the git-repack script; the intent is that later patches would start using more library facilities, but this patch is meant to be as close to a no-op as possible so it doesn't do that kind of thing. Signed-off-by: Stefan Beller Signed-off-by: Junio C Hamano --- Makefile | 2 +- builtin.h | 1 + builtin/repack.c | 387 ++++++++++++++++++ .../examples/git-repack.sh | 0 git.c | 1 + 5 files changed, 390 insertions(+), 1 deletion(-) create mode 100644 builtin/repack.c rename git-repack.sh => contrib/examples/git-repack.sh (100%) diff --git a/Makefile b/Makefile index 3588ca1b6a..69e5267f86 100644 --- a/Makefile +++ b/Makefile @@ -464,7 +464,6 @@ SCRIPT_SH += git-pull.sh SCRIPT_SH += git-quiltimport.sh SCRIPT_SH += git-rebase.sh SCRIPT_SH += git-remote-testgit.sh -SCRIPT_SH += git-repack.sh SCRIPT_SH += git-request-pull.sh SCRIPT_SH += git-stash.sh SCRIPT_SH += git-submodule.sh @@ -971,6 +970,7 @@ BUILTIN_OBJS += builtin/reflog.o BUILTIN_OBJS += builtin/remote.o BUILTIN_OBJS += builtin/remote-ext.o BUILTIN_OBJS += builtin/remote-fd.o +BUILTIN_OBJS += builtin/repack.o BUILTIN_OBJS += builtin/replace.o BUILTIN_OBJS += builtin/rerere.o BUILTIN_OBJS += builtin/reset.o diff --git a/builtin.h b/builtin.h index 8afa2def49..b56cf07abc 100644 --- a/builtin.h +++ b/builtin.h @@ -102,6 +102,7 @@ extern int cmd_reflog(int argc, const char **argv, const char *prefix); extern int cmd_remote(int argc, const char **argv, const char *prefix); extern int cmd_remote_ext(int argc, const char **argv, const char *prefix); extern int cmd_remote_fd(int argc, const char **argv, const char *prefix); +extern int cmd_repack(int argc, const char **argv, const char *prefix); extern int cmd_repo_config(int argc, const char **argv, const char *prefix); extern int cmd_rerere(int argc, const char **argv, const char *prefix); extern int cmd_reset(int argc, const char **argv, const char *prefix); diff --git a/builtin/repack.c b/builtin/repack.c new file mode 100644 index 0000000000..52846f8d72 --- /dev/null +++ b/builtin/repack.c @@ -0,0 +1,387 @@ +#include "builtin.h" +#include "cache.h" +#include "dir.h" +#include "parse-options.h" +#include "run-command.h" +#include "sigchain.h" +#include "strbuf.h" +#include "string-list.h" +#include "argv-array.h" + +static int delta_base_offset = 1; +static char *packdir, *packtmp; + +static const char *const git_repack_usage[] = { + N_("git repack [options]"), + NULL +}; + +static int repack_config(const char *var, const char *value, void *cb) +{ + if (!strcmp(var, "repack.usedeltabaseoffset")) { + delta_base_offset = git_config_bool(var, value); + return 0; + } + return git_default_config(var, value, cb); +} + +/* + * Remove temporary $GIT_OBJECT_DIRECTORY/pack/.tmp-$$-pack-* files. + */ +static void remove_temporary_files(void) +{ + struct strbuf buf = STRBUF_INIT; + size_t dirlen, prefixlen; + DIR *dir; + struct dirent *e; + + dir = opendir(packdir); + if (!dir) + return; + + /* Point at the slash at the end of ".../objects/pack/" */ + dirlen = strlen(packdir) + 1; + strbuf_addstr(&buf, packtmp); + /* Hold the length of ".tmp-%d-pack-" */ + prefixlen = buf.len - dirlen; + + while ((e = readdir(dir))) { + if (strncmp(e->d_name, buf.buf + dirlen, prefixlen)) + continue; + strbuf_setlen(&buf, dirlen); + strbuf_addstr(&buf, e->d_name); + unlink(buf.buf); + } + closedir(dir); + strbuf_release(&buf); +} + +static void remove_pack_on_signal(int signo) +{ + remove_temporary_files(); + sigchain_pop(signo); + raise(signo); +} + +/* + * Adds all packs hex strings to the fname list, which do not + * have a corresponding .keep file. + */ +static void get_non_kept_pack_filenames(struct string_list *fname_list) +{ + DIR *dir; + struct dirent *e; + char *fname; + size_t len; + + if (!(dir = opendir(packdir))) + return; + + while ((e = readdir(dir)) != NULL) { + if (suffixcmp(e->d_name, ".pack")) + continue; + + len = strlen(e->d_name) - strlen(".pack"); + fname = xmemdupz(e->d_name, len); + + if (!file_exists(mkpath("%s/%s.keep", packdir, fname))) + string_list_append_nodup(fname_list, fname); + else + free(fname); + } + closedir(dir); +} + +static void remove_redundant_pack(const char *dir_name, const char *base_name) +{ + const char *exts[] = {".pack", ".idx", ".keep"}; + int i; + struct strbuf buf = STRBUF_INIT; + size_t plen; + + strbuf_addf(&buf, "%s/%s", dir_name, base_name); + plen = buf.len; + + for (i = 0; i < ARRAY_SIZE(exts); i++) { + strbuf_setlen(&buf, plen); + strbuf_addstr(&buf, exts[i]); + unlink(buf.buf); + } + strbuf_release(&buf); +} + +#define ALL_INTO_ONE 1 +#define LOOSEN_UNREACHABLE 2 + +int cmd_repack(int argc, const char **argv, const char *prefix) +{ + const char *exts[2] = {".pack", ".idx"}; + struct child_process cmd; + struct string_list_item *item; + struct argv_array cmd_args = ARGV_ARRAY_INIT; + struct string_list names = STRING_LIST_INIT_DUP; + struct string_list rollback = STRING_LIST_INIT_NODUP; + struct string_list existing_packs = STRING_LIST_INIT_DUP; + struct strbuf line = STRBUF_INIT; + int nr_packs, ext, ret, failed; + FILE *out; + + /* variables to be filled by option parsing */ + int pack_everything = 0; + int delete_redundant = 0; + char *unpack_unreachable = NULL; + int window = 0, window_memory = 0; + int depth = 0; + int max_pack_size = 0; + int no_reuse_delta = 0, no_reuse_object = 0; + int no_update_server_info = 0; + int quiet = 0; + int local = 0; + + struct option builtin_repack_options[] = { + OPT_BIT('a', NULL, &pack_everything, + N_("pack everything in a single pack"), ALL_INTO_ONE), + OPT_BIT('A', NULL, &pack_everything, + N_("same as -a, and turn unreachable objects loose"), + LOOSEN_UNREACHABLE | ALL_INTO_ONE), + OPT_BOOL('d', NULL, &delete_redundant, + N_("remove redundant packs, and run git-prune-packed")), + OPT_BOOL('f', NULL, &no_reuse_delta, + N_("pass --no-reuse-delta to git-pack-objects")), + OPT_BOOL('F', NULL, &no_reuse_object, + N_("pass --no-reuse-object to git-pack-objects")), + OPT_BOOL('n', NULL, &no_update_server_info, + N_("do not run git-update-server-info")), + OPT__QUIET(&quiet, N_("be quiet")), + OPT_BOOL('l', "local", &local, + N_("pass --local to git-pack-objects")), + OPT_STRING(0, "unpack-unreachable", &unpack_unreachable, N_("approxidate"), + N_("with -A, do not loosen objects older than this")), + OPT_INTEGER(0, "window", &window, + N_("size of the window used for delta compression")), + OPT_INTEGER(0, "window-memory", &window_memory, + N_("same as the above, but limit memory size instead of entries count")), + OPT_INTEGER(0, "depth", &depth, + N_("limits the maximum delta depth")), + OPT_INTEGER(0, "max-pack-size", &max_pack_size, + N_("maximum size of each packfile")), + OPT_END() + }; + + git_config(repack_config, NULL); + + argc = parse_options(argc, argv, prefix, builtin_repack_options, + git_repack_usage, 0); + + packdir = mkpathdup("%s/pack", get_object_directory()); + packtmp = mkpathdup("%s/.tmp-%d-pack", packdir, (int)getpid()); + + sigchain_push_common(remove_pack_on_signal); + + argv_array_push(&cmd_args, "pack-objects"); + argv_array_push(&cmd_args, "--keep-true-parents"); + argv_array_push(&cmd_args, "--honor-pack-keep"); + argv_array_push(&cmd_args, "--non-empty"); + argv_array_push(&cmd_args, "--all"); + argv_array_push(&cmd_args, "--reflog"); + if (window) + argv_array_pushf(&cmd_args, "--window=%u", window); + if (window_memory) + argv_array_pushf(&cmd_args, "--window-memory=%u", window_memory); + if (depth) + argv_array_pushf(&cmd_args, "--depth=%u", depth); + if (max_pack_size) + argv_array_pushf(&cmd_args, "--max_pack_size=%u", max_pack_size); + if (no_reuse_delta) + argv_array_pushf(&cmd_args, "--no-reuse-delta"); + if (no_reuse_object) + argv_array_pushf(&cmd_args, "--no-reuse-object"); + + if (pack_everything & ALL_INTO_ONE) { + get_non_kept_pack_filenames(&existing_packs); + + if (existing_packs.nr && delete_redundant) { + if (unpack_unreachable) + argv_array_pushf(&cmd_args, + "--unpack-unreachable=%s", + unpack_unreachable); + else if (pack_everything & LOOSEN_UNREACHABLE) + argv_array_push(&cmd_args, + "--unpack-unreachable"); + } + } else { + argv_array_push(&cmd_args, "--unpacked"); + argv_array_push(&cmd_args, "--incremental"); + } + + if (local) + argv_array_push(&cmd_args, "--local"); + if (quiet) + argv_array_push(&cmd_args, "--quiet"); + if (delta_base_offset) + argv_array_push(&cmd_args, "--delta-base-offset"); + + argv_array_push(&cmd_args, packtmp); + + memset(&cmd, 0, sizeof(cmd)); + cmd.argv = cmd_args.argv; + cmd.git_cmd = 1; + cmd.out = -1; + cmd.no_stdin = 1; + + ret = start_command(&cmd); + if (ret) + return 1; + + nr_packs = 0; + out = xfdopen(cmd.out, "r"); + while (strbuf_getline(&line, out, '\n') != EOF) { + if (line.len != 40) + die("repack: Expecting 40 character sha1 lines only from pack-objects."); + string_list_append(&names, line.buf); + nr_packs++; + } + fclose(out); + ret = finish_command(&cmd); + if (ret) + return 1; + argv_array_clear(&cmd_args); + + if (!nr_packs && !quiet) + printf("Nothing new to pack.\n"); + + /* + * Ok we have prepared all new packfiles. + * First see if there are packs of the same name and if so + * if we can move them out of the way (this can happen if we + * repacked immediately after packing fully. + */ + failed = 0; + for_each_string_list_item(item, &names) { + for (ext = 0; ext < 2; ext++) { + char *fname, *fname_old; + fname = mkpathdup("%s/%s%s", packdir, + item->string, exts[ext]); + if (!file_exists(fname)) { + free(fname); + continue; + } + + fname_old = mkpath("%s/old-%s%s", packdir, + item->string, exts[ext]); + if (file_exists(fname_old)) + if (unlink(fname_old)) + failed = 1; + + if (!failed && rename(fname, fname_old)) { + free(fname); + failed = 1; + break; + } else { + string_list_append(&rollback, fname); + } + } + if (failed) + break; + } + if (failed) { + struct string_list rollback_failure = STRING_LIST_INIT_DUP; + for_each_string_list_item(item, &rollback) { + char *fname, *fname_old; + fname = mkpathdup("%s/%s", packdir, item->string); + fname_old = mkpath("%s/old-%s", packdir, item->string); + if (rename(fname_old, fname)) + string_list_append(&rollback_failure, fname); + free(fname); + } + + if (rollback_failure.nr) { + int i; + fprintf(stderr, + "WARNING: Some packs in use have been renamed by\n" + "WARNING: prefixing old- to their name, in order to\n" + "WARNING: replace them with the new version of the\n" + "WARNING: file. But the operation failed, and the\n" + "WARNING: attempt to rename them back to their\n" + "WARNING: original names also failed.\n" + "WARNING: Please rename them in %s manually:\n", packdir); + for (i = 0; i < rollback_failure.nr; i++) + fprintf(stderr, "WARNING: old-%s -> %s\n", + rollback_failure.items[i].string, + rollback_failure.items[i].string); + } + exit(1); + } + + /* Now the ones with the same name are out of the way... */ + for_each_string_list_item(item, &names) { + for (ext = 0; ext < 2; ext++) { + char *fname, *fname_old; + struct stat statbuffer; + fname = mkpathdup("%s/pack-%s%s", + packdir, item->string, exts[ext]); + fname_old = mkpathdup("%s-%s%s", + packtmp, item->string, exts[ext]); + if (!stat(fname_old, &statbuffer)) { + statbuffer.st_mode &= ~(S_IWUSR | S_IWGRP | S_IWOTH); + chmod(fname_old, statbuffer.st_mode); + } + if (rename(fname_old, fname)) + exit(errno); + free(fname); + free(fname_old); + } + } + + /* Remove the "old-" files */ + for_each_string_list_item(item, &names) { + for (ext = 0; ext < 2; ext++) { + char *fname; + fname = mkpath("%s/old-pack-%s%s", + packdir, + item->string, + exts[ext]); + remove_path(fname); + } + } + + /* End of pack replacement. */ + + if (delete_redundant) { + sort_string_list(&names); + for_each_string_list_item(item, &existing_packs) { + char *sha1; + size_t len = strlen(item->string); + if (len < 40) + continue; + sha1 = item->string + len - 40; + if (!string_list_has_string(&names, sha1)) + remove_redundant_pack(packdir, item->string); + } + argv_array_push(&cmd_args, "prune-packed"); + if (quiet) + argv_array_push(&cmd_args, "--quiet"); + + memset(&cmd, 0, sizeof(cmd)); + cmd.argv = cmd_args.argv; + cmd.git_cmd = 1; + run_command(&cmd); + argv_array_clear(&cmd_args); + } + + if (!no_update_server_info) { + argv_array_push(&cmd_args, "update-server-info"); + memset(&cmd, 0, sizeof(cmd)); + cmd.argv = cmd_args.argv; + cmd.git_cmd = 1; + run_command(&cmd); + argv_array_clear(&cmd_args); + } + remove_temporary_files(); + string_list_clear(&names, 0); + string_list_clear(&rollback, 0); + string_list_clear(&existing_packs, 0); + strbuf_release(&line); + + return 0; +} diff --git a/git-repack.sh b/contrib/examples/git-repack.sh similarity index 100% rename from git-repack.sh rename to contrib/examples/git-repack.sh diff --git a/git.c b/git.c index 2025f77d01..03510be95d 100644 --- a/git.c +++ b/git.c @@ -396,6 +396,7 @@ static void handle_internal_command(int argc, const char **argv) { "remote", cmd_remote, RUN_SETUP }, { "remote-ext", cmd_remote_ext }, { "remote-fd", cmd_remote_fd }, + { "repack", cmd_repack, RUN_SETUP }, { "replace", cmd_replace, RUN_SETUP }, { "repo-config", cmd_repo_config, RUN_SETUP_GENTLY }, { "rerere", cmd_rerere, RUN_SETUP },