/
sha1_name.c
1607 lines (1414 loc) · 38.9 KB
/
sha1_name.c
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#include "cache.h"
#include "tag.h"
#include "commit.h"
#include "tree.h"
#include "blob.h"
#include "tree-walk.h"
#include "refs.h"
#include "remote.h"
#include "dir.h"
#include "sha1-array.h"
static int get_sha1_oneline(const char *, unsigned char *, struct commit_list *);
typedef int (*disambiguate_hint_fn)(const unsigned char *, void *);
struct disambiguate_state {
int len; /* length of prefix in hex chars */
char hex_pfx[GIT_SHA1_HEXSZ + 1];
unsigned char bin_pfx[GIT_SHA1_RAWSZ];
disambiguate_hint_fn fn;
void *cb_data;
unsigned char candidate[GIT_SHA1_RAWSZ];
unsigned candidate_exists:1;
unsigned candidate_checked:1;
unsigned candidate_ok:1;
unsigned disambiguate_fn_used:1;
unsigned ambiguous:1;
unsigned always_call_fn:1;
};
static void update_candidates(struct disambiguate_state *ds, const unsigned char *current)
{
if (ds->always_call_fn) {
ds->ambiguous = ds->fn(current, ds->cb_data) ? 1 : 0;
return;
}
if (!ds->candidate_exists) {
/* this is the first candidate */
hashcpy(ds->candidate, current);
ds->candidate_exists = 1;
return;
} else if (!hashcmp(ds->candidate, current)) {
/* the same as what we already have seen */
return;
}
if (!ds->fn) {
/* cannot disambiguate between ds->candidate and current */
ds->ambiguous = 1;
return;
}
if (!ds->candidate_checked) {
ds->candidate_ok = ds->fn(ds->candidate, ds->cb_data);
ds->disambiguate_fn_used = 1;
ds->candidate_checked = 1;
}
if (!ds->candidate_ok) {
/* discard the candidate; we know it does not satisfy fn */
hashcpy(ds->candidate, current);
ds->candidate_checked = 0;
return;
}
/* if we reach this point, we know ds->candidate satisfies fn */
if (ds->fn(current, ds->cb_data)) {
/*
* if both current and candidate satisfy fn, we cannot
* disambiguate.
*/
ds->candidate_ok = 0;
ds->ambiguous = 1;
}
/* otherwise, current can be discarded and candidate is still good */
}
static void find_short_object_filename(struct disambiguate_state *ds)
{
struct alternate_object_database *alt;
char hex[GIT_SHA1_HEXSZ];
static struct alternate_object_database *fakeent;
if (!fakeent) {
/*
* Create a "fake" alternate object database that
* points to our own object database, to make it
* easier to get a temporary working space in
* alt->name/alt->base while iterating over the
* object databases including our own.
*/
const char *objdir = get_object_directory();
size_t objdir_len = strlen(objdir);
fakeent = xmalloc(st_add3(sizeof(*fakeent), objdir_len, 43));
memcpy(fakeent->base, objdir, objdir_len);
fakeent->name = fakeent->base + objdir_len + 1;
fakeent->name[-1] = '/';
}
fakeent->next = alt_odb_list;
xsnprintf(hex, sizeof(hex), "%.2s", ds->hex_pfx);
for (alt = fakeent; alt && !ds->ambiguous; alt = alt->next) {
struct dirent *de;
DIR *dir;
/*
* every alt_odb struct has 42 extra bytes after the base
* for exactly this purpose
*/
xsnprintf(alt->name, 42, "%.2s/", ds->hex_pfx);
dir = opendir(alt->base);
if (!dir)
continue;
while (!ds->ambiguous && (de = readdir(dir)) != NULL) {
unsigned char sha1[20];
if (strlen(de->d_name) != 38)
continue;
if (memcmp(de->d_name, ds->hex_pfx + 2, ds->len - 2))
continue;
memcpy(hex + 2, de->d_name, 38);
if (!get_sha1_hex(hex, sha1))
update_candidates(ds, sha1);
}
closedir(dir);
}
}
static int match_sha(unsigned len, const unsigned char *a, const unsigned char *b)
{
do {
if (*a != *b)
return 0;
a++;
b++;
len -= 2;
} while (len > 1);
if (len)
if ((*a ^ *b) & 0xf0)
return 0;
return 1;
}
static void unique_in_pack(struct packed_git *p,
struct disambiguate_state *ds)
{
uint32_t num, last, i, first = 0;
const unsigned char *current = NULL;
open_pack_index(p);
num = p->num_objects;
last = num;
while (first < last) {
uint32_t mid = (first + last) / 2;
const unsigned char *current;
int cmp;
current = nth_packed_object_sha1(p, mid);
cmp = hashcmp(ds->bin_pfx, current);
if (!cmp) {
first = mid;
break;
}
if (cmp > 0) {
first = mid+1;
continue;
}
last = mid;
}
/*
* At this point, "first" is the location of the lowest object
* with an object name that could match "bin_pfx". See if we have
* 0, 1 or more objects that actually match(es).
*/
for (i = first; i < num && !ds->ambiguous; i++) {
current = nth_packed_object_sha1(p, i);
if (!match_sha(ds->len, ds->bin_pfx, current))
break;
update_candidates(ds, current);
}
}
static void find_short_packed_object(struct disambiguate_state *ds)
{
struct packed_git *p;
prepare_packed_git();
for (p = packed_git; p && !ds->ambiguous; p = p->next)
unique_in_pack(p, ds);
}
#define SHORT_NAME_NOT_FOUND (-1)
#define SHORT_NAME_AMBIGUOUS (-2)
static int finish_object_disambiguation(struct disambiguate_state *ds,
unsigned char *sha1)
{
if (ds->ambiguous)
return SHORT_NAME_AMBIGUOUS;
if (!ds->candidate_exists)
return SHORT_NAME_NOT_FOUND;
if (!ds->candidate_checked)
/*
* If this is the only candidate, there is no point
* calling the disambiguation hint callback.
*
* On the other hand, if the current candidate
* replaced an earlier candidate that did _not_ pass
* the disambiguation hint callback, then we do have
* more than one objects that match the short name
* given, so we should make sure this one matches;
* otherwise, if we discovered this one and the one
* that we previously discarded in the reverse order,
* we would end up showing different results in the
* same repository!
*/
ds->candidate_ok = (!ds->disambiguate_fn_used ||
ds->fn(ds->candidate, ds->cb_data));
if (!ds->candidate_ok)
return SHORT_NAME_AMBIGUOUS;
hashcpy(sha1, ds->candidate);
return 0;
}
static int disambiguate_commit_only(const unsigned char *sha1, void *cb_data_unused)
{
int kind = sha1_object_info(sha1, NULL);
return kind == OBJ_COMMIT;
}
static int disambiguate_committish_only(const unsigned char *sha1, void *cb_data_unused)
{
struct object *obj;
int kind;
kind = sha1_object_info(sha1, NULL);
if (kind == OBJ_COMMIT)
return 1;
if (kind != OBJ_TAG)
return 0;
/* We need to do this the hard way... */
obj = deref_tag(parse_object(sha1), NULL, 0);
if (obj && obj->type == OBJ_COMMIT)
return 1;
return 0;
}
static int disambiguate_tree_only(const unsigned char *sha1, void *cb_data_unused)
{
int kind = sha1_object_info(sha1, NULL);
return kind == OBJ_TREE;
}
static int disambiguate_treeish_only(const unsigned char *sha1, void *cb_data_unused)
{
struct object *obj;
int kind;
kind = sha1_object_info(sha1, NULL);
if (kind == OBJ_TREE || kind == OBJ_COMMIT)
return 1;
if (kind != OBJ_TAG)
return 0;
/* We need to do this the hard way... */
obj = deref_tag(parse_object(sha1), NULL, 0);
if (obj && (obj->type == OBJ_TREE || obj->type == OBJ_COMMIT))
return 1;
return 0;
}
static int disambiguate_blob_only(const unsigned char *sha1, void *cb_data_unused)
{
int kind = sha1_object_info(sha1, NULL);
return kind == OBJ_BLOB;
}
static disambiguate_hint_fn default_disambiguate_hint;
int set_disambiguate_hint_config(const char *var, const char *value)
{
static const struct {
const char *name;
disambiguate_hint_fn fn;
} hints[] = {
{ "none", NULL },
{ "commit", disambiguate_commit_only },
{ "committish", disambiguate_committish_only },
{ "tree", disambiguate_tree_only },
{ "treeish", disambiguate_treeish_only },
{ "blob", disambiguate_blob_only }
};
int i;
if (!value)
return config_error_nonbool(var);
for (i = 0; i < ARRAY_SIZE(hints); i++) {
if (!strcasecmp(value, hints[i].name)) {
default_disambiguate_hint = hints[i].fn;
return 0;
}
}
return error("unknown hint type for '%s': %s", var, value);
}
static int init_object_disambiguation(const char *name, int len,
struct disambiguate_state *ds)
{
int i;
if (len < MINIMUM_ABBREV || len > GIT_SHA1_HEXSZ)
return -1;
memset(ds, 0, sizeof(*ds));
for (i = 0; i < len ;i++) {
unsigned char c = name[i];
unsigned char val;
if (c >= '0' && c <= '9')
val = c - '0';
else if (c >= 'a' && c <= 'f')
val = c - 'a' + 10;
else if (c >= 'A' && c <='F') {
val = c - 'A' + 10;
c -= 'A' - 'a';
}
else
return -1;
ds->hex_pfx[i] = c;
if (!(i & 1))
val <<= 4;
ds->bin_pfx[i >> 1] |= val;
}
ds->len = len;
ds->hex_pfx[len] = '\0';
prepare_alt_odb();
return 0;
}
static int show_ambiguous_object(const unsigned char *sha1, void *data)
{
const struct disambiguate_state *ds = data;
struct strbuf desc = STRBUF_INIT;
int type;
if (ds->fn && !ds->fn(sha1, ds->cb_data))
return 0;
type = sha1_object_info(sha1, NULL);
if (type == OBJ_COMMIT) {
struct commit *commit = lookup_commit(sha1);
if (commit) {
struct pretty_print_context pp = {0};
pp.date_mode.type = DATE_SHORT;
format_commit_message(commit, " %ad - %s", &desc, &pp);
}
} else if (type == OBJ_TAG) {
struct tag *tag = lookup_tag(sha1);
if (!parse_tag(tag) && tag->tag)
strbuf_addf(&desc, " %s", tag->tag);
}
advise(" %s %s%s",
find_unique_abbrev(sha1, DEFAULT_ABBREV),
typename(type) ? typename(type) : "unknown type",
desc.buf);
strbuf_release(&desc);
return 0;
}
static int get_short_sha1(const char *name, int len, unsigned char *sha1,
unsigned flags)
{
int status;
struct disambiguate_state ds;
int quietly = !!(flags & GET_SHA1_QUIETLY);
if (init_object_disambiguation(name, len, &ds) < 0)
return -1;
if (HAS_MULTI_BITS(flags & GET_SHA1_DISAMBIGUATORS))
die("BUG: multiple get_short_sha1 disambiguator flags");
if (flags & GET_SHA1_COMMIT)
ds.fn = disambiguate_commit_only;
else if (flags & GET_SHA1_COMMITTISH)
ds.fn = disambiguate_committish_only;
else if (flags & GET_SHA1_TREE)
ds.fn = disambiguate_tree_only;
else if (flags & GET_SHA1_TREEISH)
ds.fn = disambiguate_treeish_only;
else if (flags & GET_SHA1_BLOB)
ds.fn = disambiguate_blob_only;
else
ds.fn = default_disambiguate_hint;
find_short_object_filename(&ds);
find_short_packed_object(&ds);
status = finish_object_disambiguation(&ds, sha1);
if (!quietly && (status == SHORT_NAME_AMBIGUOUS)) {
error(_("short SHA1 %s is ambiguous"), ds.hex_pfx);
/*
* We may still have ambiguity if we simply saw a series of
* candidates that did not satisfy our hint function. In
* that case, we still want to show them, so disable the hint
* function entirely.
*/
if (!ds.ambiguous)
ds.fn = NULL;
advise(_("The candidates are:"));
for_each_abbrev(ds.hex_pfx, show_ambiguous_object, &ds);
}
return status;
}
static int collect_ambiguous(const unsigned char *sha1, void *data)
{
sha1_array_append(data, sha1);
return 0;
}
int for_each_abbrev(const char *prefix, each_abbrev_fn fn, void *cb_data)
{
struct sha1_array collect = SHA1_ARRAY_INIT;
struct disambiguate_state ds;
int ret;
if (init_object_disambiguation(prefix, strlen(prefix), &ds) < 0)
return -1;
ds.always_call_fn = 1;
ds.fn = collect_ambiguous;
ds.cb_data = &collect;
find_short_object_filename(&ds);
find_short_packed_object(&ds);
ret = sha1_array_for_each_unique(&collect, fn, cb_data);
sha1_array_clear(&collect);
return ret;
}
int find_unique_abbrev_r(char *hex, const unsigned char *sha1, int len)
{
int status, exists;
sha1_to_hex_r(hex, sha1);
if (len == 40 || !len)
return 40;
exists = has_sha1_file(sha1);
while (len < 40) {
unsigned char sha1_ret[20];
status = get_short_sha1(hex, len, sha1_ret, GET_SHA1_QUIETLY);
if (exists
? !status
: status == SHORT_NAME_NOT_FOUND) {
hex[len] = 0;
return len;
}
len++;
}
return len;
}
const char *find_unique_abbrev(const unsigned char *sha1, int len)
{
static char hex[GIT_SHA1_HEXSZ + 1];
find_unique_abbrev_r(hex, sha1, len);
return hex;
}
static int ambiguous_path(const char *path, int len)
{
int slash = 1;
int cnt;
for (cnt = 0; cnt < len; cnt++) {
switch (*path++) {
case '\0':
break;
case '/':
if (slash)
break;
slash = 1;
continue;
case '.':
continue;
default:
slash = 0;
continue;
}
break;
}
return slash;
}
static inline int at_mark(const char *string, int len,
const char **suffix, int nr)
{
int i;
for (i = 0; i < nr; i++) {
int suffix_len = strlen(suffix[i]);
if (suffix_len <= len
&& !memcmp(string, suffix[i], suffix_len))
return suffix_len;
}
return 0;
}
static inline int upstream_mark(const char *string, int len)
{
const char *suffix[] = { "@{upstream}", "@{u}" };
return at_mark(string, len, suffix, ARRAY_SIZE(suffix));
}
static inline int push_mark(const char *string, int len)
{
const char *suffix[] = { "@{push}" };
return at_mark(string, len, suffix, ARRAY_SIZE(suffix));
}
static int get_sha1_1(const char *name, int len, unsigned char *sha1, unsigned lookup_flags);
static int interpret_nth_prior_checkout(const char *name, int namelen, struct strbuf *buf);
static int get_sha1_basic(const char *str, int len, unsigned char *sha1,
unsigned int flags)
{
static const char *warn_msg = "refname '%.*s' is ambiguous.";
static const char *object_name_msg = N_(
"Git normally never creates a ref that ends with 40 hex characters\n"
"because it will be ignored when you just specify 40-hex. These refs\n"
"may be created by mistake. For example,\n"
"\n"
" git checkout -b $br $(git rev-parse ...)\n"
"\n"
"where \"$br\" is somehow empty and a 40-hex ref is created. Please\n"
"examine these refs and maybe delete them. Turn this message off by\n"
"running \"git config advice.objectNameWarning false\"");
unsigned char tmp_sha1[20];
char *real_ref = NULL;
int refs_found = 0;
int at, reflog_len, nth_prior = 0;
if (len == 40 && !get_sha1_hex(str, sha1)) {
if (warn_ambiguous_refs && warn_on_object_refname_ambiguity) {
refs_found = dwim_ref(str, len, tmp_sha1, &real_ref);
if (refs_found > 0) {
warning(warn_msg, len, str);
if (advice_object_name_warning)
fprintf(stderr, "%s\n", _(object_name_msg));
}
free(real_ref);
}
return 0;
}
/* basic@{time or number or -number} format to query ref-log */
reflog_len = at = 0;
if (len && str[len-1] == '}') {
for (at = len-4; at >= 0; at--) {
if (str[at] == '@' && str[at+1] == '{') {
if (str[at+2] == '-') {
if (at != 0)
/* @{-N} not at start */
return -1;
nth_prior = 1;
continue;
}
if (!upstream_mark(str + at, len - at) &&
!push_mark(str + at, len - at)) {
reflog_len = (len-1) - (at+2);
len = at;
}
break;
}
}
}
/* Accept only unambiguous ref paths. */
if (len && ambiguous_path(str, len))
return -1;
if (nth_prior) {
struct strbuf buf = STRBUF_INIT;
int detached;
if (interpret_nth_prior_checkout(str, len, &buf) > 0) {
detached = (buf.len == 40 && !get_sha1_hex(buf.buf, sha1));
strbuf_release(&buf);
if (detached)
return 0;
}
}
if (!len && reflog_len)
/* allow "@{...}" to mean the current branch reflog */
refs_found = dwim_ref("HEAD", 4, sha1, &real_ref);
else if (reflog_len)
refs_found = dwim_log(str, len, sha1, &real_ref);
else
refs_found = dwim_ref(str, len, sha1, &real_ref);
if (!refs_found)
return -1;
if (warn_ambiguous_refs && !(flags & GET_SHA1_QUIETLY) &&
(refs_found > 1 ||
!get_short_sha1(str, len, tmp_sha1, GET_SHA1_QUIETLY)))
warning(warn_msg, len, str);
if (reflog_len) {
int nth, i;
unsigned long at_time;
unsigned long co_time;
int co_tz, co_cnt;
/* Is it asking for N-th entry, or approxidate? */
for (i = nth = 0; 0 <= nth && i < reflog_len; i++) {
char ch = str[at+2+i];
if ('0' <= ch && ch <= '9')
nth = nth * 10 + ch - '0';
else
nth = -1;
}
if (100000000 <= nth) {
at_time = nth;
nth = -1;
} else if (0 <= nth)
at_time = 0;
else {
int errors = 0;
char *tmp = xstrndup(str + at + 2, reflog_len);
at_time = approxidate_careful(tmp, &errors);
free(tmp);
if (errors) {
free(real_ref);
return -1;
}
}
if (read_ref_at(real_ref, flags, at_time, nth, sha1, NULL,
&co_time, &co_tz, &co_cnt)) {
if (!len) {
if (starts_with(real_ref, "refs/heads/")) {
str = real_ref + 11;
len = strlen(real_ref + 11);
} else {
/* detached HEAD */
str = "HEAD";
len = 4;
}
}
if (at_time) {
if (!(flags & GET_SHA1_QUIETLY)) {
warning("Log for '%.*s' only goes "
"back to %s.", len, str,
show_date(co_time, co_tz, DATE_MODE(RFC2822)));
}
} else {
if (flags & GET_SHA1_QUIETLY) {
exit(128);
}
die("Log for '%.*s' only has %d entries.",
len, str, co_cnt);
}
}
}
free(real_ref);
return 0;
}
static int get_parent(const char *name, int len,
unsigned char *result, int idx)
{
unsigned char sha1[20];
int ret = get_sha1_1(name, len, sha1, GET_SHA1_COMMITTISH);
struct commit *commit;
struct commit_list *p;
if (ret)
return ret;
commit = lookup_commit_reference(sha1);
if (parse_commit(commit))
return -1;
if (!idx) {
hashcpy(result, commit->object.oid.hash);
return 0;
}
p = commit->parents;
while (p) {
if (!--idx) {
hashcpy(result, p->item->object.oid.hash);
return 0;
}
p = p->next;
}
return -1;
}
static int get_nth_ancestor(const char *name, int len,
unsigned char *result, int generation)
{
unsigned char sha1[20];
struct commit *commit;
int ret;
ret = get_sha1_1(name, len, sha1, GET_SHA1_COMMITTISH);
if (ret)
return ret;
commit = lookup_commit_reference(sha1);
if (!commit)
return -1;
while (generation--) {
if (parse_commit(commit) || !commit->parents)
return -1;
commit = commit->parents->item;
}
hashcpy(result, commit->object.oid.hash);
return 0;
}
struct object *peel_to_type(const char *name, int namelen,
struct object *o, enum object_type expected_type)
{
if (name && !namelen)
namelen = strlen(name);
while (1) {
if (!o || (!o->parsed && !parse_object(o->oid.hash)))
return NULL;
if (expected_type == OBJ_ANY || o->type == expected_type)
return o;
if (o->type == OBJ_TAG)
o = ((struct tag*) o)->tagged;
else if (o->type == OBJ_COMMIT)
o = &(((struct commit *) o)->tree->object);
else {
if (name)
error("%.*s: expected %s type, but the object "
"dereferences to %s type",
namelen, name, typename(expected_type),
typename(o->type));
return NULL;
}
}
}
static int peel_onion(const char *name, int len, unsigned char *sha1,
unsigned lookup_flags)
{
unsigned char outer[20];
const char *sp;
unsigned int expected_type = 0;
struct object *o;
/*
* "ref^{type}" dereferences ref repeatedly until you cannot
* dereference anymore, or you get an object of given type,
* whichever comes first. "ref^{}" means just dereference
* tags until you get a non-tag. "ref^0" is a shorthand for
* "ref^{commit}". "commit^{tree}" could be used to find the
* top-level tree of the given commit.
*/
if (len < 4 || name[len-1] != '}')
return -1;
for (sp = name + len - 1; name <= sp; sp--) {
int ch = *sp;
if (ch == '{' && name < sp && sp[-1] == '^')
break;
}
if (sp <= name)
return -1;
sp++; /* beginning of type name, or closing brace for empty */
if (starts_with(sp, "commit}"))
expected_type = OBJ_COMMIT;
else if (starts_with(sp, "tag}"))
expected_type = OBJ_TAG;
else if (starts_with(sp, "tree}"))
expected_type = OBJ_TREE;
else if (starts_with(sp, "blob}"))
expected_type = OBJ_BLOB;
else if (starts_with(sp, "object}"))
expected_type = OBJ_ANY;
else if (sp[0] == '}')
expected_type = OBJ_NONE;
else if (sp[0] == '/')
expected_type = OBJ_COMMIT;
else
return -1;
lookup_flags &= ~GET_SHA1_DISAMBIGUATORS;
if (expected_type == OBJ_COMMIT)
lookup_flags |= GET_SHA1_COMMITTISH;
else if (expected_type == OBJ_TREE)
lookup_flags |= GET_SHA1_TREEISH;
if (get_sha1_1(name, sp - name - 2, outer, lookup_flags))
return -1;
o = parse_object(outer);
if (!o)
return -1;
if (!expected_type) {
o = deref_tag(o, name, sp - name - 2);
if (!o || (!o->parsed && !parse_object(o->oid.hash)))
return -1;
hashcpy(sha1, o->oid.hash);
return 0;
}
/*
* At this point, the syntax look correct, so
* if we do not get the needed object, we should
* barf.
*/
o = peel_to_type(name, len, o, expected_type);
if (!o)
return -1;
hashcpy(sha1, o->oid.hash);
if (sp[0] == '/') {
/* "$commit^{/foo}" */
char *prefix;
int ret;
struct commit_list *list = NULL;
/*
* $commit^{/}. Some regex implementation may reject.
* We don't need regex anyway. '' pattern always matches.
*/
if (sp[1] == '}')
return 0;
prefix = xstrndup(sp + 1, name + len - 1 - (sp + 1));
commit_list_insert((struct commit *)o, &list);
ret = get_sha1_oneline(prefix, sha1, list);
free(prefix);
return ret;
}
return 0;
}
static int get_describe_name(const char *name, int len, unsigned char *sha1)
{
const char *cp;
unsigned flags = GET_SHA1_QUIETLY | GET_SHA1_COMMIT;
for (cp = name + len - 1; name + 2 <= cp; cp--) {
char ch = *cp;
if (!isxdigit(ch)) {
/* We must be looking at g in "SOMETHING-g"
* for it to be describe output.
*/
if (ch == 'g' && cp[-1] == '-') {
cp++;
len -= cp - name;
return get_short_sha1(cp, len, sha1, flags);
}
}
}
return -1;
}
static int get_sha1_1(const char *name, int len, unsigned char *sha1, unsigned lookup_flags)
{
int ret, has_suffix;
const char *cp;
/*
* "name~3" is "name^^^", "name~" is "name~1", and "name^" is "name^1".
*/
has_suffix = 0;
for (cp = name + len - 1; name <= cp; cp--) {
int ch = *cp;
if ('0' <= ch && ch <= '9')
continue;
if (ch == '~' || ch == '^')
has_suffix = ch;
break;
}
if (has_suffix) {
int num = 0;
int len1 = cp - name;
cp++;
while (cp < name + len)
num = num * 10 + *cp++ - '0';
if (!num && len1 == len - 1)
num = 1;
if (has_suffix == '^')
return get_parent(name, len1, sha1, num);
/* else if (has_suffix == '~') -- goes without saying */
return get_nth_ancestor(name, len1, sha1, num);
}
ret = peel_onion(name, len, sha1, lookup_flags);
if (!ret)
return 0;
ret = get_sha1_basic(name, len, sha1, lookup_flags);
if (!ret)
return 0;
/* It could be describe output that is "SOMETHING-gXXXX" */
ret = get_describe_name(name, len, sha1);
if (!ret)
return 0;
return get_short_sha1(name, len, sha1, lookup_flags);
}
/*
* This interprets names like ':/Initial revision of "git"' by searching
* through history and returning the first commit whose message starts
* the given regular expression.
*
* For negative-matching, prefix the pattern-part with '!-', like: ':/!-WIP'.
*
* For a literal '!' character at the beginning of a pattern, you have to repeat
* that, like: ':/!!foo'
*
* For future extension, all other sequences beginning with ':/!' are reserved.
*/
/* Remember to update object flag allocation in object.h */
#define ONELINE_SEEN (1u<<20)
static int handle_one_ref(const char *path, const struct object_id *oid,
int flag, void *cb_data)
{
struct commit_list **list = cb_data;
struct object *object = parse_object(oid->hash);
if (!object)
return 0;
if (object->type == OBJ_TAG) {
object = deref_tag(object, path, strlen(path));
if (!object)
return 0;
}
if (object->type != OBJ_COMMIT)
return 0;
commit_list_insert((struct commit *)object, list);
return 0;
}
static int get_sha1_oneline(const char *prefix, unsigned char *sha1,
struct commit_list *list)
{
struct commit_list *backup = NULL, *l;
int found = 0;
int negative = 0;
regex_t regex;
if (prefix[0] == '!') {
prefix++;
if (prefix[0] == '-') {
prefix++;
negative = 1;
} else if (prefix[0] != '!') {
return -1;
}
}
if (regcomp(®ex, prefix, REG_EXTENDED))
return -1;
for (l = list; l; l = l->next) {
l->item->object.flags |= ONELINE_SEEN;
commit_list_insert(l->item, &backup);
}
while (list) {
const char *p, *buf;
struct commit *commit;
int matches;
commit = pop_most_recent_commit(&list, ONELINE_SEEN);
if (!parse_object(commit->object.oid.hash))
continue;
buf = get_commit_buffer(commit, NULL);
p = strstr(buf, "\n\n");
matches = negative ^ (p && !regexec(®ex, p + 2, 0, NULL, 0));