git/builtin/fast-export.c
Junio C Hamano 8061ae8b46 Merge branch 'jk/commit-buffer-length'
Move "commit->buffer" out of the in-core commit object and keep
track of their lengths.  Use this to optimize the code paths to
validate GPG signatures in commit objects.

* jk/commit-buffer-length:
  reuse cached commit buffer when parsing signatures
  commit: record buffer length in cache
  commit: convert commit->buffer to a slab
  commit-slab: provide a static initializer
  use get_commit_buffer everywhere
  convert logmsg_reencode to get_commit_buffer
  use get_commit_buffer to avoid duplicate code
  use get_cached_commit_buffer where appropriate
  provide helpers to access the commit buffer
  provide a helper to set the commit buffer
  provide a helper to free commit buffer
  sequencer: use logmsg_reencode in get_message
  logmsg_reencode: return const buffer
  do not create "struct commit" with xcalloc
  commit: push commit_index update into alloc_commit_node
  alloc: include any-object allocations in alloc_report
  replace dangerous uses of strbuf_attach
  commit_tree: take a pointer/len pair rather than a const strbuf
2014-07-02 12:53:02 -07:00

795 lines
20 KiB
C

/*
* "git fast-export" builtin command
*
* Copyright (C) 2007 Johannes E. Schindelin
*/
#include "builtin.h"
#include "cache.h"
#include "commit.h"
#include "object.h"
#include "tag.h"
#include "diff.h"
#include "diffcore.h"
#include "log-tree.h"
#include "revision.h"
#include "decorate.h"
#include "string-list.h"
#include "utf8.h"
#include "parse-options.h"
#include "quote.h"
#include "remote.h"
static const char *fast_export_usage[] = {
N_("git fast-export [rev-list-opts]"),
NULL
};
static int progress;
static enum { ABORT, VERBATIM, WARN, WARN_STRIP, STRIP } signed_tag_mode = ABORT;
static enum { ERROR, DROP, REWRITE } tag_of_filtered_mode = ERROR;
static int fake_missing_tagger;
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 parse_opt_signed_tag_mode(const struct option *opt,
const char *arg, int unset)
{
if (unset || !strcmp(arg, "abort"))
signed_tag_mode = ABORT;
else if (!strcmp(arg, "verbatim") || !strcmp(arg, "ignore"))
signed_tag_mode = VERBATIM;
else if (!strcmp(arg, "warn"))
signed_tag_mode = WARN;
else if (!strcmp(arg, "warn-strip"))
signed_tag_mode = WARN_STRIP;
else if (!strcmp(arg, "strip"))
signed_tag_mode = STRIP;
else
return error("Unknown signed-tags mode: %s", arg);
return 0;
}
static int parse_opt_tag_of_filtered_mode(const struct option *opt,
const char *arg, int unset)
{
if (unset || !strcmp(arg, "abort"))
tag_of_filtered_mode = ERROR;
else if (!strcmp(arg, "drop"))
tag_of_filtered_mode = DROP;
else if (!strcmp(arg, "rewrite"))
tag_of_filtered_mode = REWRITE;
else
return error("Unknown tag-of-filtered mode: %s", arg);
return 0;
}
static struct decoration idnums;
static uint32_t last_idnum;
static int has_unshown_parent(struct commit *commit)
{
struct commit_list *parent;
for (parent = commit->parents; parent; parent = parent->next)
if (!(parent->item->object.flags & SHOWN) &&
!(parent->item->object.flags & UNINTERESTING))
return 1;
return 0;
}
/* Since intptr_t is C99, we do not use it here */
static inline uint32_t *mark_to_ptr(uint32_t mark)
{
return ((uint32_t *)NULL) + mark;
}
static inline uint32_t ptr_to_mark(void * mark)
{
return (uint32_t *)mark - (uint32_t *)NULL;
}
static inline void mark_object(struct object *object, uint32_t mark)
{
add_decoration(&idnums, object, mark_to_ptr(mark));
}
static inline void mark_next_object(struct object *object)
{
mark_object(object, ++last_idnum);
}
static int get_object_mark(struct object *object)
{
void *decoration = lookup_decoration(&idnums, object);
if (!decoration)
return 0;
return ptr_to_mark(decoration);
}
static void show_progress(void)
{
static int counter = 0;
if (!progress)
return;
if ((++counter % progress) == 0)
printf("progress %d objects\n", counter);
}
static void export_blob(const unsigned char *sha1)
{
unsigned long size;
enum object_type type;
char *buf;
struct object *object;
int eaten;
if (no_data)
return;
if (is_null_sha1(sha1))
return;
object = lookup_object(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 (!object)
die("Could not read blob %s", sha1_to_hex(sha1));
mark_next_object(object);
printf("blob\nmark :%"PRIu32"\ndata %lu\n", last_idnum, size);
if (size && fwrite(buf, size, 1, stdout) != 1)
die_errno ("Could not write blob '%s'", sha1_to_hex(sha1));
printf("\n");
show_progress();
object->flags |= SHOWN;
if (!eaten)
free(buf);
}
static int depth_first(const void *a_, const void *b_)
{
const struct diff_filepair *a = *((const struct diff_filepair **)a_);
const struct diff_filepair *b = *((const struct diff_filepair **)b_);
const char *name_a, *name_b;
int len_a, len_b, len;
int cmp;
name_a = a->one ? a->one->path : a->two->path;
name_b = b->one ? b->one->path : b->two->path;
len_a = strlen(name_a);
len_b = strlen(name_b);
len = (len_a < len_b) ? len_a : len_b;
/* strcmp will sort 'd' before 'd/e', we want 'd/e' before 'd' */
cmp = memcmp(name_a, name_b, len);
if (cmp)
return cmp;
cmp = len_b - len_a;
if (cmp)
return cmp;
/*
* Move 'R'ename entries last so that all references of the file
* appear in the output before it is renamed (e.g., when a file
* was copied and renamed in the same commit).
*/
return (a->status == 'R') - (b->status == 'R');
}
static void print_path(const char *path)
{
int need_quote = quote_c_style(path, NULL, NULL, 0);
if (need_quote)
quote_c_style(path, NULL, stdout, 0);
else if (strchr(path, ' '))
printf("\"%s\"", path);
else
printf("%s", path);
}
static void show_filemodify(struct diff_queue_struct *q,
struct diff_options *options, void *data)
{
int i;
/*
* Handle files below a directory first, in case they are all deleted
* and the directory changes to a file or symlink.
*/
qsort(q->queue, q->nr, sizeof(q->queue[0]), depth_first);
for (i = 0; i < q->nr; i++) {
struct diff_filespec *ospec = q->queue[i]->one;
struct diff_filespec *spec = q->queue[i]->two;
switch (q->queue[i]->status) {
case DIFF_STATUS_DELETED:
printf("D ");
print_path(spec->path);
putchar('\n');
break;
case DIFF_STATUS_COPIED:
case DIFF_STATUS_RENAMED:
printf("%c ", q->queue[i]->status);
print_path(ospec->path);
putchar(' ');
print_path(spec->path);
putchar('\n');
if (!hashcmp(ospec->sha1, spec->sha1) &&
ospec->mode == spec->mode)
break;
/* fallthrough */
case DIFF_STATUS_TYPE_CHANGED:
case DIFF_STATUS_MODIFIED:
case DIFF_STATUS_ADDED:
/*
* Links refer to objects in another repositories;
* output the SHA-1 verbatim.
*/
if (no_data || S_ISGITLINK(spec->mode))
printf("M %06o %s ", spec->mode,
sha1_to_hex(spec->sha1));
else {
struct object *object = lookup_object(spec->sha1);
printf("M %06o :%d ", spec->mode,
get_object_mark(object));
}
print_path(spec->path);
putchar('\n');
break;
default:
die("Unexpected comparison status '%c' for %s, %s",
q->queue[i]->status,
ospec->path ? ospec->path : "none",
spec->path ? spec->path : "none");
}
}
}
static const char *find_encoding(const char *begin, const char *end)
{
const char *needle = "\nencoding ";
char *bol, *eol;
bol = memmem(begin, end ? end - begin : strlen(begin),
needle, strlen(needle));
if (!bol)
return git_commit_encoding;
bol += strlen(needle);
eol = strchrnul(bol, '\n');
*eol = '\0';
return bol;
}
static void handle_commit(struct commit *commit, struct rev_info *rev)
{
int saved_output_format = rev->diffopt.output_format;
const char *commit_buffer;
const char *author, *author_end, *committer, *committer_end;
const char *encoding, *message;
char *reencoded = NULL;
struct commit_list *p;
int i;
rev->diffopt.output_format = DIFF_FORMAT_CALLBACK;
parse_commit_or_die(commit);
commit_buffer = get_commit_buffer(commit, NULL);
author = strstr(commit_buffer, "\nauthor ");
if (!author)
die ("Could not find author in commit %s",
sha1_to_hex(commit->object.sha1));
author++;
author_end = strchrnul(author, '\n');
committer = strstr(author_end, "\ncommitter ");
if (!committer)
die ("Could not find committer in commit %s",
sha1_to_hex(commit->object.sha1));
committer++;
committer_end = strchrnul(committer, '\n');
message = strstr(committer_end, "\n\n");
encoding = find_encoding(committer_end, message);
if (message)
message += 2;
if (commit->parents &&
get_object_mark(&commit->parents->item->object) != 0 &&
!full_tree) {
parse_commit_or_die(commit->parents->item);
diff_tree_sha1(commit->parents->item->tree->object.sha1,
commit->tree->object.sha1, "", &rev->diffopt);
}
else
diff_root_tree_sha1(commit->tree->object.sha1,
"", &rev->diffopt);
/* Export the referenced blobs, and remember the marks. */
for (i = 0; i < diff_queued_diff.nr; i++)
if (!S_ISGITLINK(diff_queued_diff.queue[i]->two->mode))
export_blob(diff_queued_diff.queue[i]->two->sha1);
mark_next_object(&commit->object);
if (!is_encoding_utf8(encoding))
reencoded = reencode_string(message, "UTF-8", encoding);
if (!commit->parents)
printf("reset %s\n", (const char*)commit->util);
printf("commit %s\nmark :%"PRIu32"\n%.*s\n%.*s\ndata %u\n%s",
(const char *)commit->util, last_idnum,
(int)(author_end - author), author,
(int)(committer_end - committer), committer,
(unsigned)(reencoded
? strlen(reencoded) : message
? strlen(message) : 0),
reencoded ? reencoded : message ? message : "");
free(reencoded);
unuse_commit_buffer(commit, commit_buffer);
for (i = 0, p = commit->parents; p; p = p->next) {
int mark = get_object_mark(&p->item->object);
if (!mark)
continue;
if (i == 0)
printf("from :%d\n", mark);
else
printf("merge :%d\n", mark);
i++;
}
if (full_tree)
printf("deleteall\n");
log_tree_diff_flush(rev);
rev->diffopt.output_format = saved_output_format;
printf("\n");
show_progress();
}
static void handle_tail(struct object_array *commits, struct rev_info *revs)
{
struct commit *commit;
while (commits->nr) {
commit = (struct commit *)commits->objects[commits->nr - 1].item;
if (has_unshown_parent(commit))
return;
handle_commit(commit, revs);
commits->nr--;
}
}
static void handle_tag(const char *name, struct tag *tag)
{
unsigned long size;
enum object_type type;
char *buf;
const char *tagger, *tagger_end, *message;
size_t message_size = 0;
struct object *tagged;
int tagged_mark;
struct commit *p;
/* Trees have no identifier in fast-export output, thus we have no way
* to output tags of trees, tags of tags of trees, etc. Simply omit
* such tags.
*/
tagged = tag->tagged;
while (tagged->type == OBJ_TAG) {
tagged = ((struct tag *)tagged)->tagged;
}
if (tagged->type == OBJ_TREE) {
warning("Omitting tag %s,\nsince tags of trees (or tags of tags of trees, etc.) are not supported.",
sha1_to_hex(tag->object.sha1));
return;
}
buf = read_sha1_file(tag->object.sha1, &type, &size);
if (!buf)
die ("Could not read tag %s", sha1_to_hex(tag->object.sha1));
message = memmem(buf, size, "\n\n", 2);
if (message) {
message += 2;
message_size = strlen(message);
}
tagger = memmem(buf, message ? message - buf : size, "\ntagger ", 8);
if (!tagger) {
if (fake_missing_tagger)
tagger = "tagger Unspecified Tagger "
"<unspecified-tagger> 0 +0000";
else
tagger = "";
tagger_end = tagger + strlen(tagger);
} else {
tagger++;
tagger_end = strchrnul(tagger, '\n');
}
/* handle signed tags */
if (message) {
const char *signature = strstr(message,
"\n-----BEGIN PGP SIGNATURE-----\n");
if (signature)
switch(signed_tag_mode) {
case ABORT:
die ("Encountered signed tag %s; use "
"--signed-tags=<mode> to handle it.",
sha1_to_hex(tag->object.sha1));
case WARN:
warning ("Exporting signed tag %s",
sha1_to_hex(tag->object.sha1));
/* fallthru */
case VERBATIM:
break;
case WARN_STRIP:
warning ("Stripping signature from tag %s",
sha1_to_hex(tag->object.sha1));
/* fallthru */
case STRIP:
message_size = signature + 1 - message;
break;
}
}
/* handle tag->tagged having been filtered out due to paths specified */
tagged = tag->tagged;
tagged_mark = get_object_mark(tagged);
if (!tagged_mark) {
switch(tag_of_filtered_mode) {
case ABORT:
die ("Tag %s tags unexported object; use "
"--tag-of-filtered-object=<mode> to handle it.",
sha1_to_hex(tag->object.sha1));
case DROP:
/* Ignore this tag altogether */
return;
case REWRITE:
if (tagged->type != OBJ_COMMIT) {
die ("Tag %s tags unexported %s!",
sha1_to_hex(tag->object.sha1),
typename(tagged->type));
}
p = (struct commit *)tagged;
for (;;) {
if (p->parents && p->parents->next)
break;
if (p->object.flags & UNINTERESTING)
break;
if (!(p->object.flags & TREESAME))
break;
if (!p->parents)
die ("Can't find replacement commit for tag %s\n",
sha1_to_hex(tag->object.sha1));
p = p->parents->item;
}
tagged_mark = get_object_mark(&p->object);
}
}
if (starts_with(name, "refs/tags/"))
name += 10;
printf("tag %s\nfrom :%d\n%.*s%sdata %d\n%.*s\n",
name, tagged_mark,
(int)(tagger_end - tagger), tagger,
tagger == tagger_end ? "" : "\n",
(int)message_size, (int)message_size, message ? message : "");
}
static struct commit *get_commit(struct rev_cmdline_entry *e, char *full_name)
{
switch (e->item->type) {
case OBJ_COMMIT:
return (struct commit *)e->item;
case OBJ_TAG: {
struct tag *tag = (struct tag *)e->item;
/* handle nested tags */
while (tag && tag->object.type == OBJ_TAG) {
parse_object(tag->object.sha1);
string_list_append(&extra_refs, full_name)->util = tag;
tag = (struct tag *)tag->tagged;
}
if (!tag)
die("Tag %s points nowhere?", e->name);
return (struct commit *)tag;
break;
}
default:
return NULL;
}
}
static void get_tags_and_duplicates(struct rev_cmdline_info *info)
{
int i;
for (i = 0; i < info->nr; i++) {
struct rev_cmdline_entry *e = info->rev + i;
unsigned char sha1[20];
struct commit *commit;
char *full_name;
if (e->flags & UNINTERESTING)
continue;
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.",
e->name,
typename(e->item->type));
continue;
}
switch(commit->object.type) {
case OBJ_COMMIT:
break;
case OBJ_BLOB:
export_blob(commit->object.sha1);
continue;
default: /* OBJ_TAG (nested tags) is already handled */
warning("Tag points to object of unexpected type %s, skipping.",
typename(commit->object.type));
continue;
}
/*
* This ref will not be updated through a commit, lets make
* sure it gets properly updated eventually.
*/
if (commit->util || commit->object.flags & SHOWN)
string_list_append(&extra_refs, full_name)->util = commit;
if (!commit->util)
commit->util = full_name;
}
}
static void handle_tags_and_duplicates(void)
{
struct commit *commit;
int i;
for (i = extra_refs.nr - 1; i >= 0; i--) {
const char *name = extra_refs.items[i].string;
struct object *object = extra_refs.items[i].util;
switch (object->type) {
case OBJ_TAG:
handle_tag(name, (struct tag *)object);
break;
case OBJ_COMMIT:
/* create refs pointing to already seen commits */
commit = (struct commit *)object;
printf("reset %s\nfrom :%d\n\n", name,
get_object_mark(&commit->object));
show_progress();
break;
}
}
}
static void export_marks(char *file)
{
unsigned int i;
uint32_t mark;
struct object_decoration *deco = idnums.hash;
FILE *f;
int e = 0;
f = fopen(file, "w");
if (!f)
die_errno("Unable to open marks file %s for writing.", file);
for (i = 0; i < idnums.size; i++) {
if (deco->base && deco->base->type == 1) {
mark = ptr_to_mark(deco->decoration);
if (fprintf(f, ":%"PRIu32" %s\n", mark,
sha1_to_hex(deco->base->sha1)) < 0) {
e = 1;
break;
}
}
deco++;
}
e |= ferror(f);
e |= fclose(f);
if (e)
error("Unable to write marks file %s.", file);
}
static void import_marks(char *input_file)
{
char line[512];
FILE *f = fopen(input_file, "r");
if (!f)
die_errno("cannot read '%s'", input_file);
while (fgets(line, sizeof(line), f)) {
uint32_t mark;
char *line_end, *mark_end;
unsigned char sha1[20];
struct object *object;
struct commit *commit;
enum object_type type;
line_end = strchr(line, '\n');
if (line[0] != ':' || !line_end)
die("corrupt mark line: %s", line);
*line_end = '\0';
mark = strtoumax(line + 1, &mark_end, 10);
if (!mark || mark_end == line + 1
|| *mark_end != ' ' || get_sha1_hex(mark_end + 1, sha1))
die("corrupt mark line: %s", line);
if (last_idnum < mark)
last_idnum = mark;
type = sha1_object_info(sha1, NULL);
if (type < 0)
die("object not found: %s", sha1_to_hex(sha1));
if (type != OBJ_COMMIT)
/* only commits */
continue;
commit = lookup_commit(sha1);
if (!commit)
die("not a commit? can't happen: %s", sha1_to_hex(sha1));
object = &commit->object;
if (object->flags & SHOWN)
error("Object %s already has a mark", sha1_to_hex(sha1));
mark_object(object, mark);
object->flags |= SHOWN;
}
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;
struct object_array commits = OBJECT_ARRAY_INIT;
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")),
OPT_CALLBACK(0, "signed-tags", &signed_tag_mode, N_("mode"),
N_("select handling of signed tags"),
parse_opt_signed_tag_mode),
OPT_CALLBACK(0, "tag-of-filtered-object", &tag_of_filtered_mode, N_("mode"),
N_("select handling of tags that tag filtered objects"),
parse_opt_tag_of_filtered_mode),
OPT_STRING(0, "export-marks", &export_filename, N_("file"),
N_("Dump marks to this file")),
OPT_STRING(0, "import-marks", &import_filename, N_("file"),
N_("Import marks from this file")),
OPT_BOOL(0, "fake-missing-tagger", &fake_missing_tagger,
N_("Fake a tagger when tags lack one")),
OPT_BOOL(0, "full-tree", &full_tree,
N_("Output full tree for each commit")),
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_END()
};
if (argc == 1)
usage_with_options (fast_export_usage, options);
/* we handle encodings */
git_config(git_default_config, NULL);
init_revisions(&revs, 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);
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");
if (import_filename)
import_marks(import_filename);
lastimportid = last_idnum;
if (import_filename && revs.prune_data.nr)
full_tree = 1;
get_tags_and_duplicates(&revs.cmdline);
if (prepare_revision_walk(&revs))
die("revision walk setup failed");
revs.diffopt.format_callback = show_filemodify;
DIFF_OPT_SET(&revs.diffopt, RECURSIVE);
while ((commit = get_revision(&revs))) {
if (has_unshown_parent(commit)) {
add_object_array(&commit->object, NULL, &commits);
}
else {
handle_commit(commit, &revs);
handle_tail(&commits, &revs);
}
}
handle_tags_and_duplicates();
handle_deletes();
if (export_filename && lastimportid != last_idnum)
export_marks(export_filename);
if (use_done_feature)
printf("done\n");
free_refspec(refspecs_nr, refspecs);
return 0;
}