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-rw-r--r--builtin/fast-export.c351
1 files changed, 338 insertions, 13 deletions
diff --git a/builtin/fast-export.c b/builtin/fast-export.c
index 7ee5e08442..b8182c241d 100644
--- a/builtin/fast-export.c
+++ b/builtin/fast-export.c
@@ -17,6 +17,8 @@
#include "utf8.h"
#include "parse-options.h"
#include "quote.h"
+#include "remote.h"
+#include "blob.h"
static const char *fast_export_usage[] = {
N_("git fast-export [rev-list-opts]"),
@@ -31,6 +33,9 @@ static int use_done_feature;
static int no_data;
static int full_tree;
static struct string_list extra_refs = STRING_LIST_INIT_NODUP;
+static struct refspec *refspecs;
+static int refspecs_nr;
+static int anonymize;
static int parse_opt_signed_tag_mode(const struct option *opt,
const char *arg, int unset)
@@ -78,6 +83,76 @@ static int has_unshown_parent(struct commit *commit)
return 0;
}
+struct anonymized_entry {
+ struct hashmap_entry hash;
+ const char *orig;
+ size_t orig_len;
+ const char *anon;
+ size_t anon_len;
+};
+
+static int anonymized_entry_cmp(const void *va, const void *vb,
+ const void *data)
+{
+ const struct anonymized_entry *a = va, *b = vb;
+ return a->orig_len != b->orig_len ||
+ memcmp(a->orig, b->orig, a->orig_len);
+}
+
+/*
+ * Basically keep a cache of X->Y so that we can repeatedly replace
+ * the same anonymized string with another. The actual generation
+ * is farmed out to the generate function.
+ */
+static const void *anonymize_mem(struct hashmap *map,
+ void *(*generate)(const void *, size_t *),
+ const void *orig, size_t *len)
+{
+ struct anonymized_entry key, *ret;
+
+ if (!map->cmpfn)
+ hashmap_init(map, anonymized_entry_cmp, 0);
+
+ hashmap_entry_init(&key, memhash(orig, *len));
+ key.orig = orig;
+ key.orig_len = *len;
+ ret = hashmap_get(map, &key, NULL);
+
+ if (!ret) {
+ ret = xmalloc(sizeof(*ret));
+ hashmap_entry_init(&ret->hash, key.hash.hash);
+ ret->orig = xstrdup(orig);
+ ret->orig_len = *len;
+ ret->anon = generate(orig, len);
+ ret->anon_len = *len;
+ hashmap_put(map, ret);
+ }
+
+ *len = ret->anon_len;
+ return ret->anon;
+}
+
+/*
+ * We anonymize each component of a path individually,
+ * so that paths a/b and a/c will share a common root.
+ * The paths are cached via anonymize_mem so that repeated
+ * lookups for "a" will yield the same value.
+ */
+static void anonymize_path(struct strbuf *out, const char *path,
+ struct hashmap *map,
+ void *(*generate)(const void *, size_t *))
+{
+ while (*path) {
+ const char *end_of_component = strchrnul(path, '/');
+ size_t len = end_of_component - path;
+ const char *c = anonymize_mem(map, generate, path, &len);
+ strbuf_add(out, c, len);
+ path = end_of_component;
+ if (*path)
+ strbuf_addch(out, *path++);
+ }
+}
+
/* Since intptr_t is C99, we do not use it here */
static inline uint32_t *mark_to_ptr(uint32_t mark)
{
@@ -116,6 +191,26 @@ static void show_progress(void)
printf("progress %d objects\n", counter);
}
+/*
+ * Ideally we would want some transformation of the blob data here
+ * that is unreversible, but would still be the same size and have
+ * the same data relationship to other blobs (so that we get the same
+ * delta and packing behavior as the original). But the first and last
+ * requirements there are probably mutually exclusive, so let's take
+ * the easy way out for now, and just generate arbitrary content.
+ *
+ * There's no need to cache this result with anonymize_mem, since
+ * we already handle blob content caching with marks.
+ */
+static char *anonymize_blob(unsigned long *size)
+{
+ static int counter;
+ struct strbuf out = STRBUF_INIT;
+ strbuf_addf(&out, "anonymous blob %d", counter++);
+ *size = out.len;
+ return strbuf_detach(&out, NULL);
+}
+
static void export_blob(const unsigned char *sha1)
{
unsigned long size;
@@ -134,12 +229,19 @@ static void export_blob(const unsigned char *sha1)
if (object && object->flags & SHOWN)
return;
- buf = read_sha1_file(sha1, &type, &size);
- if (!buf)
- die ("Could not read blob %s", sha1_to_hex(sha1));
- if (check_sha1_signature(sha1, buf, size, typename(type)) < 0)
- die("sha1 mismatch in blob %s", sha1_to_hex(sha1));
- object = parse_object_buffer(sha1, type, size, buf, &eaten);
+ if (anonymize) {
+ buf = anonymize_blob(&size);
+ object = (struct object *)lookup_blob(sha1);
+ eaten = 0;
+ } else {
+ buf = read_sha1_file(sha1, &type, &size);
+ if (!buf)
+ die ("Could not read blob %s", sha1_to_hex(sha1));
+ if (check_sha1_signature(sha1, buf, size, typename(type)) < 0)
+ die("sha1 mismatch in blob %s", sha1_to_hex(sha1));
+ object = parse_object_buffer(sha1, type, size, buf, &eaten);
+ }
+
if (!object)
die("Could not read blob %s", sha1_to_hex(sha1));
@@ -187,7 +289,7 @@ static int depth_first(const void *a_, const void *b_)
return (a->status == 'R') - (b->status == 'R');
}
-static void print_path(const char *path)
+static void print_path_1(const char *path)
{
int need_quote = quote_c_style(path, NULL, NULL, 0);
if (need_quote)
@@ -198,6 +300,43 @@ static void print_path(const char *path)
printf("%s", path);
}
+static void *anonymize_path_component(const void *path, size_t *len)
+{
+ static int counter;
+ struct strbuf out = STRBUF_INIT;
+ strbuf_addf(&out, "path%d", counter++);
+ return strbuf_detach(&out, len);
+}
+
+static void print_path(const char *path)
+{
+ if (!anonymize)
+ print_path_1(path);
+ else {
+ static struct hashmap paths;
+ static struct strbuf anon = STRBUF_INIT;
+
+ anonymize_path(&anon, path, &paths, anonymize_path_component);
+ print_path_1(anon.buf);
+ strbuf_reset(&anon);
+ }
+}
+
+static void *generate_fake_sha1(const void *old, size_t *len)
+{
+ static uint32_t counter = 1; /* avoid null sha1 */
+ unsigned char *out = xcalloc(20, 1);
+ put_be32(out + 16, counter++);
+ return out;
+}
+
+static const unsigned char *anonymize_sha1(const unsigned char *sha1)
+{
+ static struct hashmap sha1s;
+ size_t len = 20;
+ return anonymize_mem(&sha1s, generate_fake_sha1, sha1, &len);
+}
+
static void show_filemodify(struct diff_queue_struct *q,
struct diff_options *options, void *data)
{
@@ -242,7 +381,9 @@ static void show_filemodify(struct diff_queue_struct *q,
*/
if (no_data || S_ISGITLINK(spec->mode))
printf("M %06o %s ", spec->mode,
- sha1_to_hex(spec->sha1));
+ sha1_to_hex(anonymize ?
+ anonymize_sha1(spec->sha1) :
+ spec->sha1));
else {
struct object *object = lookup_object(spec->sha1);
printf("M %06o :%d ", spec->mode,
@@ -276,6 +417,114 @@ static const char *find_encoding(const char *begin, const char *end)
return bol;
}
+static void *anonymize_ref_component(const void *old, size_t *len)
+{
+ static int counter;
+ struct strbuf out = STRBUF_INIT;
+ strbuf_addf(&out, "ref%d", counter++);
+ return strbuf_detach(&out, len);
+}
+
+static const char *anonymize_refname(const char *refname)
+{
+ /*
+ * If any of these prefixes is found, we will leave it intact
+ * so that tags remain tags and so forth.
+ */
+ static const char *prefixes[] = {
+ "refs/heads/",
+ "refs/tags/",
+ "refs/remotes/",
+ "refs/"
+ };
+ static struct hashmap refs;
+ static struct strbuf anon = STRBUF_INIT;
+ int i;
+
+ /*
+ * We also leave "master" as a special case, since it does not reveal
+ * anything interesting.
+ */
+ if (!strcmp(refname, "refs/heads/master"))
+ return refname;
+
+ strbuf_reset(&anon);
+ for (i = 0; i < ARRAY_SIZE(prefixes); i++) {
+ if (skip_prefix(refname, prefixes[i], &refname)) {
+ strbuf_addstr(&anon, prefixes[i]);
+ break;
+ }
+ }
+
+ anonymize_path(&anon, refname, &refs, anonymize_ref_component);
+ return anon.buf;
+}
+
+/*
+ * We do not even bother to cache commit messages, as they are unlikely
+ * to be repeated verbatim, and it is not that interesting when they are.
+ */
+static char *anonymize_commit_message(const char *old)
+{
+ static int counter;
+ return xstrfmt("subject %d\n\nbody\n", counter++);
+}
+
+static struct hashmap idents;
+static void *anonymize_ident(const void *old, size_t *len)
+{
+ static int counter;
+ struct strbuf out = STRBUF_INIT;
+ strbuf_addf(&out, "User %d <user%d@example.com>", counter, counter);
+ counter++;
+ return strbuf_detach(&out, len);
+}
+
+/*
+ * Our strategy here is to anonymize the names and email addresses,
+ * but keep timestamps intact, as they influence things like traversal
+ * order (and by themselves should not be too revealing).
+ */
+static void anonymize_ident_line(const char **beg, const char **end)
+{
+ static struct strbuf buffers[] = { STRBUF_INIT, STRBUF_INIT };
+ static unsigned which_buffer;
+
+ struct strbuf *out;
+ struct ident_split split;
+ const char *end_of_header;
+
+ out = &buffers[which_buffer++];
+ which_buffer %= ARRAY_SIZE(buffers);
+ strbuf_reset(out);
+
+ /* skip "committer", "author", "tagger", etc */
+ end_of_header = strchr(*beg, ' ');
+ if (!end_of_header)
+ die("BUG: malformed line fed to anonymize_ident_line: %.*s",
+ (int)(*end - *beg), *beg);
+ end_of_header++;
+ strbuf_add(out, *beg, end_of_header - *beg);
+
+ if (!split_ident_line(&split, end_of_header, *end - end_of_header) &&
+ split.date_begin) {
+ const char *ident;
+ size_t len;
+
+ len = split.mail_end - split.name_begin;
+ ident = anonymize_mem(&idents, anonymize_ident,
+ split.name_begin, &len);
+ strbuf_add(out, ident, len);
+ strbuf_addch(out, ' ');
+ strbuf_add(out, split.date_begin, split.tz_end - split.date_begin);
+ } else {
+ strbuf_addstr(out, "Malformed Ident <malformed@example.com> 0 -0000");
+ }
+
+ *beg = out->buf;
+ *end = out->buf + out->len;
+}
+
static void handle_commit(struct commit *commit, struct rev_info *rev)
{
int saved_output_format = rev->diffopt.output_format;
@@ -284,12 +533,13 @@ static void handle_commit(struct commit *commit, struct rev_info *rev)
const char *encoding, *message;
char *reencoded = NULL;
struct commit_list *p;
+ const char *refname;
int i;
rev->diffopt.output_format = DIFF_FORMAT_CALLBACK;
parse_commit_or_die(commit);
- commit_buffer = get_commit_buffer(commit);
+ commit_buffer = get_commit_buffer(commit, NULL);
author = strstr(commit_buffer, "\nauthor ");
if (!author)
die ("Could not find author in commit %s",
@@ -323,13 +573,22 @@ static void handle_commit(struct commit *commit, struct rev_info *rev)
if (!S_ISGITLINK(diff_queued_diff.queue[i]->two->mode))
export_blob(diff_queued_diff.queue[i]->two->sha1);
+ refname = commit->util;
+ if (anonymize) {
+ refname = anonymize_refname(refname);
+ anonymize_ident_line(&committer, &committer_end);
+ anonymize_ident_line(&author, &author_end);
+ }
+
mark_next_object(&commit->object);
- if (!is_encoding_utf8(encoding))
+ if (anonymize)
+ reencoded = anonymize_commit_message(message);
+ else if (!is_encoding_utf8(encoding))
reencoded = reencode_string(message, "UTF-8", encoding);
if (!commit->parents)
- printf("reset %s\n", (const char*)commit->util);
+ printf("reset %s\n", refname);
printf("commit %s\nmark :%"PRIu32"\n%.*s\n%.*s\ndata %u\n%s",
- (const char *)commit->util, last_idnum,
+ refname, last_idnum,
(int)(author_end - author), author,
(int)(committer_end - committer), committer,
(unsigned)(reencoded
@@ -360,6 +619,14 @@ static void handle_commit(struct commit *commit, struct rev_info *rev)
show_progress();
}
+static void *anonymize_tag(const void *old, size_t *len)
+{
+ static int counter;
+ struct strbuf out = STRBUF_INIT;
+ strbuf_addf(&out, "tag message %d", counter++);
+ return strbuf_detach(&out, len);
+}
+
static void handle_tail(struct object_array *commits, struct rev_info *revs)
{
struct commit *commit;
@@ -416,6 +683,17 @@ static void handle_tag(const char *name, struct tag *tag)
} else {
tagger++;
tagger_end = strchrnul(tagger, '\n');
+ if (anonymize)
+ anonymize_ident_line(&tagger, &tagger_end);
+ }
+
+ if (anonymize) {
+ name = anonymize_refname(name);
+ if (message) {
+ static struct hashmap tags;
+ message = anonymize_mem(&tags, anonymize_tag,
+ message, &message_size);
+ }
}
/* handle signed tags */
@@ -528,6 +806,15 @@ static void get_tags_and_duplicates(struct rev_cmdline_info *info)
if (dwim_ref(e->name, strlen(e->name), sha1, &full_name) != 1)
continue;
+ if (refspecs) {
+ char *private;
+ private = apply_refspecs(refspecs, refspecs_nr, full_name);
+ if (private) {
+ free(full_name);
+ full_name = private;
+ }
+ }
+
commit = get_commit(e, full_name);
if (!commit) {
warning("%s: Unexpected object of type %s, skipping.",
@@ -572,6 +859,8 @@ static void handle_tags_and_duplicates(void)
handle_tag(name, (struct tag *)object);
break;
case OBJ_COMMIT:
+ if (anonymize)
+ name = anonymize_refname(name);
/* create refs pointing to already seen commits */
commit = (struct commit *)object;
printf("reset %s\nfrom :%d\n\n", name,
@@ -664,6 +953,19 @@ static void import_marks(char *input_file)
fclose(f);
}
+static void handle_deletes(void)
+{
+ int i;
+ for (i = 0; i < refspecs_nr; i++) {
+ struct refspec *refspec = &refspecs[i];
+ if (*refspec->src)
+ continue;
+
+ printf("reset %s\nfrom %s\n\n",
+ refspec->dst, sha1_to_hex(null_sha1));
+ }
+}
+
int cmd_fast_export(int argc, const char **argv, const char *prefix)
{
struct rev_info revs;
@@ -671,6 +973,7 @@ int cmd_fast_export(int argc, const char **argv, const char *prefix)
struct commit *commit;
char *export_filename = NULL, *import_filename = NULL;
uint32_t lastimportid;
+ struct string_list refspecs_list = STRING_LIST_INIT_NODUP;
struct option options[] = {
OPT_INTEGER(0, "progress", &progress,
N_("show progress after <n> objects")),
@@ -691,6 +994,9 @@ int cmd_fast_export(int argc, const char **argv, const char *prefix)
OPT_BOOL(0, "use-done-feature", &use_done_feature,
N_("Use the done feature to terminate the stream")),
OPT_BOOL(0, "no-data", &no_data, N_("Skip output of blob data")),
+ OPT_STRING_LIST(0, "refspec", &refspecs_list, N_("refspec"),
+ N_("Apply refspec to exported refs")),
+ OPT_BOOL(0, "anonymize", &anonymize, N_("anonymize output")),
OPT_END()
};
@@ -704,11 +1010,27 @@ int cmd_fast_export(int argc, const char **argv, const char *prefix)
revs.topo_order = 1;
revs.show_source = 1;
revs.rewrite_parents = 1;
+ argc = parse_options(argc, argv, prefix, options, fast_export_usage,
+ PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN);
argc = setup_revisions(argc, argv, &revs, NULL);
- argc = parse_options(argc, argv, prefix, options, fast_export_usage, 0);
if (argc > 1)
usage_with_options (fast_export_usage, options);
+ if (refspecs_list.nr) {
+ const char **refspecs_str;
+ int i;
+
+ refspecs_str = xmalloc(sizeof(*refspecs_str) * refspecs_list.nr);
+ for (i = 0; i < refspecs_list.nr; i++)
+ refspecs_str[i] = refspecs_list.items[i].string;
+
+ refspecs_nr = refspecs_list.nr;
+ refspecs = parse_fetch_refspec(refspecs_nr, refspecs_str);
+
+ string_list_clear(&refspecs_list, 1);
+ free(refspecs_str);
+ }
+
if (use_done_feature)
printf("feature done\n");
@@ -736,6 +1058,7 @@ int cmd_fast_export(int argc, const char **argv, const char *prefix)
}
handle_tags_and_duplicates();
+ handle_deletes();
if (export_filename && lastimportid != last_idnum)
export_marks(export_filename);
@@ -743,5 +1066,7 @@ int cmd_fast_export(int argc, const char **argv, const char *prefix)
if (use_done_feature)
printf("done\n");
+ free_refspec(refspecs_nr, refspecs);
+
return 0;
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-18 04:21:52 +0000