diff options
| -rw-r--r-- | Documentation/git-update-server-info.txt | 11 | ||||
| -rw-r--r-- | server-info.c | 140 | ||||
| -rwxr-xr-x | t/t5200-update-server-info.sh | 41 |
3 files changed, 158 insertions, 34 deletions
diff --git a/Documentation/git-update-server-info.txt b/Documentation/git-update-server-info.txt index bd0e36492f..969bb2e15f 100644 --- a/Documentation/git-update-server-info.txt +++ b/Documentation/git-update-server-info.txt @@ -9,7 +9,7 @@ git-update-server-info - Update auxiliary info file to help dumb servers SYNOPSIS -------- [verse] -'git update-server-info' [--force] +'git update-server-info' DESCRIPTION ----------- @@ -19,15 +19,6 @@ $GIT_OBJECT_DIRECTORY/info directories to help clients discover what references and packs the server has. This command generates such auxiliary files. - -OPTIONS -------- - --f:: ---force:: - Update the info files from scratch. - - OUTPUT ------ diff --git a/server-info.c b/server-info.c index 41274d098b..e68f785c2f 100644 --- a/server-info.c +++ b/server-info.c @@ -6,82 +6,174 @@ #include "tag.h" #include "packfile.h" #include "object-store.h" +#include "strbuf.h" + +struct update_info_ctx { + FILE *cur_fp; + FILE *old_fp; /* becomes NULL if it differs from cur_fp */ + struct strbuf cur_sb; + struct strbuf old_sb; +}; + +static void uic_mark_stale(struct update_info_ctx *uic) +{ + fclose(uic->old_fp); + uic->old_fp = NULL; +} + +static int uic_is_stale(const struct update_info_ctx *uic) +{ + return uic->old_fp == NULL; +} + +static int uic_printf(struct update_info_ctx *uic, const char *fmt, ...) +{ + va_list ap; + int ret = -1; + + va_start(ap, fmt); + + if (uic_is_stale(uic)) { + ret = vfprintf(uic->cur_fp, fmt, ap); + } else { + ssize_t r; + struct strbuf *cur = &uic->cur_sb; + struct strbuf *old = &uic->old_sb; + + strbuf_reset(cur); + strbuf_vinsertf(cur, 0, fmt, ap); + + strbuf_reset(old); + strbuf_grow(old, cur->len); + r = fread(old->buf, 1, cur->len, uic->old_fp); + if (r != cur->len || memcmp(old->buf, cur->buf, r)) + uic_mark_stale(uic); + + if (fwrite(cur->buf, 1, cur->len, uic->cur_fp) == cur->len) + ret = 0; + } + + va_end(ap); + + return ret; +} /* * Create the file "path" by writing to a temporary file and renaming * it into place. The contents of the file come from "generate", which * should return non-zero if it encounters an error. */ -static int update_info_file(char *path, int (*generate)(FILE *)) +static int update_info_file(char *path, + int (*generate)(struct update_info_ctx *), + int force) { char *tmp = mkpathdup("%s_XXXXXX", path); int ret = -1; int fd = -1; - FILE *fp = NULL, *to_close; + FILE *to_close; + struct update_info_ctx uic = { + .cur_fp = NULL, + .old_fp = NULL, + .cur_sb = STRBUF_INIT, + .old_sb = STRBUF_INIT + }; safe_create_leading_directories(path); fd = git_mkstemp_mode(tmp, 0666); if (fd < 0) goto out; - to_close = fp = fdopen(fd, "w"); - if (!fp) + to_close = uic.cur_fp = fdopen(fd, "w"); + if (!uic.cur_fp) goto out; fd = -1; - ret = generate(fp); + + /* no problem on ENOENT and old_fp == NULL, it's stale, now */ + if (!force) + uic.old_fp = fopen_or_warn(path, "r"); + + /* + * uic_printf will compare incremental comparison aginst old_fp + * and mark uic as stale if needed + */ + ret = generate(&uic); if (ret) goto out; - fp = NULL; + + /* new file may be shorter than the old one, check here */ + if (!uic_is_stale(&uic)) { + struct stat st; + long new_len = ftell(uic.cur_fp); + int old_fd = fileno(uic.old_fp); + + if (new_len < 0) { + ret = -1; + goto out; + } + if (fstat(old_fd, &st) || (st.st_size != (size_t)new_len)) + uic_mark_stale(&uic); + } + + uic.cur_fp = NULL; if (fclose(to_close)) goto out; - if (adjust_shared_perm(tmp) < 0) - goto out; - if (rename(tmp, path) < 0) - goto out; + + if (uic_is_stale(&uic)) { + if (adjust_shared_perm(tmp) < 0) + goto out; + if (rename(tmp, path) < 0) + goto out; + } else { + unlink(tmp); + } ret = 0; out: if (ret) { error_errno("unable to update %s", path); - if (fp) - fclose(fp); + if (uic.cur_fp) + fclose(uic.cur_fp); else if (fd >= 0) close(fd); unlink(tmp); } free(tmp); + if (uic.old_fp) + fclose(uic.old_fp); + strbuf_release(&uic.old_sb); + strbuf_release(&uic.cur_sb); return ret; } static int add_info_ref(const char *path, const struct object_id *oid, int flag, void *cb_data) { - FILE *fp = cb_data; + struct update_info_ctx *uic = cb_data; struct object *o = parse_object(the_repository, oid); if (!o) return -1; - if (fprintf(fp, "%s %s\n", oid_to_hex(oid), path) < 0) + if (uic_printf(uic, "%s %s\n", oid_to_hex(oid), path) < 0) return -1; if (o->type == OBJ_TAG) { o = deref_tag(the_repository, o, path, 0); if (o) - if (fprintf(fp, "%s %s^{}\n", + if (uic_printf(uic, "%s %s^{}\n", oid_to_hex(&o->oid), path) < 0) return -1; } return 0; } -static int generate_info_refs(FILE *fp) +static int generate_info_refs(struct update_info_ctx *uic) { - return for_each_ref(add_info_ref, fp); + return for_each_ref(add_info_ref, uic); } -static int update_info_refs(void) +static int update_info_refs(int force) { char *path = git_pathdup("info/refs"); - int ret = update_info_file(path, generate_info_refs); + int ret = update_info_file(path, generate_info_refs, force); free(path); return ret; } @@ -236,14 +328,14 @@ static void free_pack_info(void) free(info); } -static int write_pack_info_file(FILE *fp) +static int write_pack_info_file(struct update_info_ctx *uic) { int i; for (i = 0; i < num_pack; i++) { - if (fprintf(fp, "P %s\n", pack_basename(info[i]->p)) < 0) + if (uic_printf(uic, "P %s\n", pack_basename(info[i]->p)) < 0) return -1; } - if (fputc('\n', fp) == EOF) + if (uic_printf(uic, "\n") < 0) return -1; return 0; } @@ -254,7 +346,7 @@ static int update_info_packs(int force) int ret; init_pack_info(infofile, force); - ret = update_info_file(infofile, write_pack_info_file); + ret = update_info_file(infofile, write_pack_info_file, force); free_pack_info(); free(infofile); return ret; @@ -269,7 +361,7 @@ int update_server_info(int force) */ int errs = 0; - errs = errs | update_info_refs(); + errs = errs | update_info_refs(force); errs = errs | update_info_packs(force); /* remove leftover rev-cache file if there is any */ diff --git a/t/t5200-update-server-info.sh b/t/t5200-update-server-info.sh new file mode 100755 index 0000000000..21a58eecb9 --- /dev/null +++ b/t/t5200-update-server-info.sh @@ -0,0 +1,41 @@ +#!/bin/sh + +test_description='Test git update-server-info' + +. ./test-lib.sh + +test_expect_success 'setup' 'test_commit file' + +test_expect_success 'create info/refs' ' + git update-server-info && + test_path_is_file .git/info/refs +' + +test_expect_success 'modify and store mtime' ' + test-tool chmtime =0 .git/info/refs && + test-tool chmtime --get .git/info/refs >a +' + +test_expect_success 'info/refs is not needlessly overwritten' ' + git update-server-info && + test-tool chmtime --get .git/info/refs >b && + test_cmp a b +' + +test_expect_success 'info/refs can be forced to update' ' + git update-server-info -f && + test-tool chmtime --get .git/info/refs >b && + ! test_cmp a b +' + +test_expect_success 'info/refs updates when changes are made' ' + test-tool chmtime =0 .git/info/refs && + test-tool chmtime --get .git/info/refs >b && + test_cmp a b && + git update-ref refs/heads/foo HEAD && + git update-server-info && + test-tool chmtime --get .git/info/refs >b && + ! test_cmp a b +' + +test_done |