--- /dev/null
+#include "cache.h"
+#include "config.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"
+#include "packfile.h"
+#include "object-store.h"
+#include "repository.h"
+
+static int get_oid_oneline(const char *, struct object_id *, struct commit_list *);
+
+typedef int (*disambiguate_hint_fn)(const struct object_id *, void *);
+
+struct disambiguate_state {
+ int len; /* length of prefix in hex chars */
+ char hex_pfx[GIT_MAX_HEXSZ + 1];
+ struct object_id bin_pfx;
+
+ disambiguate_hint_fn fn;
+ void *cb_data;
+ struct object_id candidate;
+ 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 struct object_id *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 */
+ oidcpy(&ds->candidate, current);
+ ds->candidate_exists = 1;
+ return;
+ } else if (!oidcmp(&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 */
+ oidcpy(&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 int append_loose_object(const struct object_id *oid, const char *path,
+ void *data)
+{
+ oid_array_append(data, oid);
+ return 0;
+}
+
+static int match_sha(unsigned, const unsigned char *, const unsigned char *);
+
+static void find_short_object_filename(struct disambiguate_state *ds)
+{
+ int subdir_nr = ds->bin_pfx.hash[0];
+ struct alternate_object_database *alt;
+ 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.
+ */
+ fakeent = alloc_alt_odb(get_object_directory());
+ }
+ fakeent->next = the_repository->objects->alt_odb_list;
+
+ for (alt = fakeent; alt && !ds->ambiguous; alt = alt->next) {
+ int pos;
+
+ if (!alt->loose_objects_subdir_seen[subdir_nr]) {
+ struct strbuf *buf = alt_scratch_buf(alt);
+ for_each_file_in_obj_subdir(subdir_nr, buf,
+ append_loose_object,
+ NULL, NULL,
+ &alt->loose_objects_cache);
+ alt->loose_objects_subdir_seen[subdir_nr] = 1;
+ }
+
+ pos = oid_array_lookup(&alt->loose_objects_cache, &ds->bin_pfx);
+ if (pos < 0)
+ pos = -1 - pos;
+ while (!ds->ambiguous && pos < alt->loose_objects_cache.nr) {
+ const struct object_id *oid;
+ oid = alt->loose_objects_cache.oid + pos;
+ if (!match_sha(ds->len, ds->bin_pfx.hash, oid->hash))
+ break;
+ update_candidates(ds, oid);
+ pos++;
+ }
+ }
+}
+
+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, i, first = 0;
+ const struct object_id *current = NULL;
+
+ if (open_pack_index(p) || !p->num_objects)
+ return;
+
+ num = p->num_objects;
+ bsearch_pack(&ds->bin_pfx, p, &first);
+
+ /*
+ * 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++) {
+ struct object_id oid;
+ current = nth_packed_object_oid(&oid, p, i);
+ if (!match_sha(ds->len, ds->bin_pfx.hash, current->hash))
+ break;
+ update_candidates(ds, current);
+ }
+}
+
+static void find_short_packed_object(struct disambiguate_state *ds)
+{
+ struct packed_git *p;
+
+ for (p = get_packed_git(the_repository); 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,
+ struct object_id *oid)
+{
+ 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;
+
+ oidcpy(oid, &ds->candidate);
+ return 0;
+}
+
+static int disambiguate_commit_only(const struct object_id *oid, void *cb_data_unused)
+{
+ int kind = oid_object_info(the_repository, oid, NULL);
+ return kind == OBJ_COMMIT;
+}
+
+static int disambiguate_committish_only(const struct object_id *oid, void *cb_data_unused)
+{
+ struct object *obj;
+ int kind;
+
+ kind = oid_object_info(the_repository, oid, 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(oid), NULL, 0);
+ if (obj && obj->type == OBJ_COMMIT)
+ return 1;
+ return 0;
+}
+
+static int disambiguate_tree_only(const struct object_id *oid, void *cb_data_unused)
+{
+ int kind = oid_object_info(the_repository, oid, NULL);
+ return kind == OBJ_TREE;
+}
+
+static int disambiguate_treeish_only(const struct object_id *oid, void *cb_data_unused)
+{
+ struct object *obj;
+ int kind;
+
+ kind = oid_object_info(the_repository, oid, 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(oid), NULL, 0);
+ if (obj && (obj->type == OBJ_TREE || obj->type == OBJ_COMMIT))
+ return 1;
+ return 0;
+}
+
+static int disambiguate_blob_only(const struct object_id *oid, void *cb_data_unused)
+{
+ int kind = oid_object_info(the_repository, oid, 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.hash[i >> 1] |= val;
+ }
+
+ ds->len = len;
+ ds->hex_pfx[len] = '\0';
+ prepare_alt_odb(the_repository);
+ return 0;
+}
+
+static int show_ambiguous_object(const struct object_id *oid, void *data)
+{
+ const struct disambiguate_state *ds = data;
+ struct strbuf desc = STRBUF_INIT;
+ int type;
+
+ if (ds->fn && !ds->fn(oid, ds->cb_data))
+ return 0;
+
+ type = oid_object_info(the_repository, oid, NULL);
+ if (type == OBJ_COMMIT) {
+ struct commit *commit = lookup_commit(oid);
+ 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(oid);
+ if (!parse_tag(tag) && tag->tag)
+ strbuf_addf(&desc, " %s", tag->tag);
+ }
+
+ advise(" %s %s%s",
+ find_unique_abbrev(oid, DEFAULT_ABBREV),
+ type_name(type) ? type_name(type) : "unknown type",
+ desc.buf);
+
+ strbuf_release(&desc);
+ return 0;
+}
+
+static int collect_ambiguous(const struct object_id *oid, void *data)
+{
+ oid_array_append(data, oid);
+ return 0;
+}
+
+static int sort_ambiguous(const void *a, const void *b)
+{
+ int a_type = oid_object_info(the_repository, a, NULL);
+ int b_type = oid_object_info(the_repository, b, NULL);
+ int a_type_sort;
+ int b_type_sort;
+
+ /*
+ * Sorts by hash within the same object type, just as
+ * oid_array_for_each_unique() would do.
+ */
+ if (a_type == b_type)
+ return oidcmp(a, b);
+
+ /*
+ * Between object types show tags, then commits, and finally
+ * trees and blobs.
+ *
+ * The object_type enum is commit, tree, blob, tag, but we
+ * want tag, commit, tree blob. Cleverly (perhaps too
+ * cleverly) do that with modulus, since the enum assigns 1 to
+ * commit, so tag becomes 0.
+ */
+ a_type_sort = a_type % 4;
+ b_type_sort = b_type % 4;
+ return a_type_sort > b_type_sort ? 1 : -1;
+}
+
+static int get_short_oid(const char *name, int len, struct object_id *oid,
+ unsigned flags)
+{
+ int status;
+ struct disambiguate_state ds;
+ int quietly = !!(flags & GET_OID_QUIETLY);
+
+ if (init_object_disambiguation(name, len, &ds) < 0)
+ return -1;
+
+ if (HAS_MULTI_BITS(flags & GET_OID_DISAMBIGUATORS))
+ BUG("multiple get_short_oid disambiguator flags");
+
+ if (flags & GET_OID_COMMIT)
+ ds.fn = disambiguate_commit_only;
+ else if (flags & GET_OID_COMMITTISH)
+ ds.fn = disambiguate_committish_only;
+ else if (flags & GET_OID_TREE)
+ ds.fn = disambiguate_tree_only;
+ else if (flags & GET_OID_TREEISH)
+ ds.fn = disambiguate_treeish_only;
+ else if (flags & GET_OID_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, oid);
+
+ if (!quietly && (status == SHORT_NAME_AMBIGUOUS)) {
+ struct oid_array collect = OID_ARRAY_INIT;
+
+ 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, collect_ambiguous, &collect);
+ QSORT(collect.oid, collect.nr, sort_ambiguous);
+
+ if (oid_array_for_each(&collect, show_ambiguous_object, &ds))
+ BUG("show_ambiguous_object shouldn't return non-zero");
+ oid_array_clear(&collect);
+ }
+
+ return status;
+}
+
+int for_each_abbrev(const char *prefix, each_abbrev_fn fn, void *cb_data)
+{
+ struct oid_array collect = OID_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 = oid_array_for_each_unique(&collect, fn, cb_data);
+ oid_array_clear(&collect);
+ return ret;
+}
+
+/*
+ * Return the slot of the most-significant bit set in "val". There are various
+ * ways to do this quickly with fls() or __builtin_clzl(), but speed is
+ * probably not a big deal here.
+ */
+static unsigned msb(unsigned long val)
+{
+ unsigned r = 0;
+ while (val >>= 1)
+ r++;
+ return r;
+}
+
+struct min_abbrev_data {
+ unsigned int init_len;
+ unsigned int cur_len;
+ char *hex;
+ const struct object_id *oid;
+};
+
+static inline char get_hex_char_from_oid(const struct object_id *oid,
+ unsigned int pos)
+{
+ static const char hex[] = "0123456789abcdef";
+
+ if ((pos & 1) == 0)
+ return hex[oid->hash[pos >> 1] >> 4];
+ else
+ return hex[oid->hash[pos >> 1] & 0xf];
+}
+
+static int extend_abbrev_len(const struct object_id *oid, void *cb_data)
+{
+ struct min_abbrev_data *mad = cb_data;
+
+ unsigned int i = mad->init_len;
+ while (mad->hex[i] && mad->hex[i] == get_hex_char_from_oid(oid, i))
+ i++;
+
+ if (i < GIT_MAX_RAWSZ && i >= mad->cur_len)
+ mad->cur_len = i + 1;
+
+ return 0;
+}
+
+static void find_abbrev_len_for_pack(struct packed_git *p,
+ struct min_abbrev_data *mad)
+{
+ int match = 0;
+ uint32_t num, first = 0;
+ struct object_id oid;
+ const struct object_id *mad_oid;
+
+ if (open_pack_index(p) || !p->num_objects)
+ return;
+
+ num = p->num_objects;
+ mad_oid = mad->oid;
+ match = bsearch_pack(mad_oid, p, &first);
+
+ /*
+ * first is now the position in the packfile where we would insert
+ * mad->hash if it does not exist (or the position of mad->hash if
+ * it does exist). Hence, we consider a maximum of two objects
+ * nearby for the abbreviation length.
+ */
+ mad->init_len = 0;
+ if (!match) {
+ if (nth_packed_object_oid(&oid, p, first))
+ extend_abbrev_len(&oid, mad);
+ } else if (first < num - 1) {
+ if (nth_packed_object_oid(&oid, p, first + 1))
+ extend_abbrev_len(&oid, mad);
+ }
+ if (first > 0) {
+ if (nth_packed_object_oid(&oid, p, first - 1))
+ extend_abbrev_len(&oid, mad);
+ }
+ mad->init_len = mad->cur_len;
+}
+
+static void find_abbrev_len_packed(struct min_abbrev_data *mad)
+{
+ struct packed_git *p;
+
+ for (p = get_packed_git(the_repository); p; p = p->next)
+ find_abbrev_len_for_pack(p, mad);
+}
+
+int find_unique_abbrev_r(char *hex, const struct object_id *oid, int len)
+{
+ struct disambiguate_state ds;
+ struct min_abbrev_data mad;
+ struct object_id oid_ret;
+ if (len < 0) {
+ unsigned long count = approximate_object_count();
+ /*
+ * Add one because the MSB only tells us the highest bit set,
+ * not including the value of all the _other_ bits (so "15"
+ * is only one off of 2^4, but the MSB is the 3rd bit.
+ */
+ len = msb(count) + 1;
+ /*
+ * We now know we have on the order of 2^len objects, which
+ * expects a collision at 2^(len/2). But we also care about hex
+ * chars, not bits, and there are 4 bits per hex. So all
+ * together we need to divide by 2 and round up.
+ */
+ len = DIV_ROUND_UP(len, 2);
+ /*
+ * For very small repos, we stick with our regular fallback.
+ */
+ if (len < FALLBACK_DEFAULT_ABBREV)
+ len = FALLBACK_DEFAULT_ABBREV;
+ }
+
+ oid_to_hex_r(hex, oid);
+ if (len == GIT_SHA1_HEXSZ || !len)
+ return GIT_SHA1_HEXSZ;
+
+ mad.init_len = len;
+ mad.cur_len = len;
+ mad.hex = hex;
+ mad.oid = oid;
+
+ find_abbrev_len_packed(&mad);
+
+ if (init_object_disambiguation(hex, mad.cur_len, &ds) < 0)
+ return -1;
+
+ ds.fn = extend_abbrev_len;
+ ds.always_call_fn = 1;
+ ds.cb_data = (void *)&mad;
+
+ find_short_object_filename(&ds);
+ (void)finish_object_disambiguation(&ds, &oid_ret);
+
+ hex[mad.cur_len] = 0;
+ return mad.cur_len;
+}
+
+const char *find_unique_abbrev(const struct object_id *oid, int len)
+{
+ static int bufno;
+ static char hexbuffer[4][GIT_MAX_HEXSZ + 1];
+ char *hex = hexbuffer[bufno];
+ bufno = (bufno + 1) % ARRAY_SIZE(hexbuffer);
+ find_unique_abbrev_r(hex, oid, 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
+ && !strncasecmp(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_oid_1(const char *name, int len, struct object_id *oid, unsigned lookup_flags);
+static int interpret_nth_prior_checkout(const char *name, int namelen, struct strbuf *buf);
+
+static int get_oid_basic(const char *str, int len, struct object_id *oid,
+ 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\"");
+ struct object_id tmp_oid;
+ char *real_ref = NULL;
+ int refs_found = 0;
+ int at, reflog_len, nth_prior = 0;
+
+ if (len == GIT_SHA1_HEXSZ && !get_oid_hex(str, oid)) {
+ if (warn_ambiguous_refs && warn_on_object_refname_ambiguity) {
+ refs_found = dwim_ref(str, len, &tmp_oid, &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 == GIT_SHA1_HEXSZ && !get_oid_hex(buf.buf, oid));
+ strbuf_release(&buf);
+ if (detached)
+ return 0;
+ }
+ }
+
+ if (!len && reflog_len)
+ /* allow "@{...}" to mean the current branch reflog */
+ refs_found = dwim_ref("HEAD", 4, oid, &real_ref);
+ else if (reflog_len)
+ refs_found = dwim_log(str, len, oid, &real_ref);
+ else
+ refs_found = dwim_ref(str, len, oid, &real_ref);
+
+ if (!refs_found)
+ return -1;
+
+ if (warn_ambiguous_refs && !(flags & GET_OID_QUIETLY) &&
+ (refs_found > 1 ||
+ !get_short_oid(str, len, &tmp_oid, GET_OID_QUIETLY)))
+ warning(warn_msg, len, str);
+
+ if (reflog_len) {
+ int nth, i;
+ timestamp_t at_time;
+ timestamp_t 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, oid, 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_OID_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_OID_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,
+ struct object_id *result, int idx)
+{
+ struct object_id oid;
+ int ret = get_oid_1(name, len, &oid, GET_OID_COMMITTISH);
+ struct commit *commit;
+ struct commit_list *p;
+
+ if (ret)
+ return ret;
+ commit = lookup_commit_reference(&oid);
+ if (parse_commit(commit))
+ return -1;
+ if (!idx) {
+ oidcpy(result, &commit->object.oid);
+ return 0;
+ }
+ p = commit->parents;
+ while (p) {
+ if (!--idx) {
+ oidcpy(result, &p->item->object.oid);
+ return 0;
+ }
+ p = p->next;
+ }
+ return -1;
+}
+
+static int get_nth_ancestor(const char *name, int len,
+ struct object_id *result, int generation)
+{
+ struct object_id oid;
+ struct commit *commit;
+ int ret;
+
+ ret = get_oid_1(name, len, &oid, GET_OID_COMMITTISH);
+ if (ret)
+ return ret;
+ commit = lookup_commit_reference(&oid);
+ if (!commit)
+ return -1;
+
+ while (generation--) {
+ if (parse_commit(commit) || !commit->parents)
+ return -1;
+ commit = commit->parents->item;
+ }
+ oidcpy(result, &commit->object.oid);
+ 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)))
+ 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 = &(get_commit_tree(((struct commit *)o))->object);
+ else {
+ if (name)
+ error("%.*s: expected %s type, but the object "
+ "dereferences to %s type",
+ namelen, name, type_name(expected_type),
+ type_name(o->type));
+ return NULL;
+ }
+ }
+}
+
+static int peel_onion(const char *name, int len, struct object_id *oid,
+ unsigned lookup_flags)
+{
+ struct object_id outer;
+ 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_OID_DISAMBIGUATORS;
+ if (expected_type == OBJ_COMMIT)
+ lookup_flags |= GET_OID_COMMITTISH;
+ else if (expected_type == OBJ_TREE)
+ lookup_flags |= GET_OID_TREEISH;
+
+ if (get_oid_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)))
+ return -1;
+ oidcpy(oid, &o->oid);
+ 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;
+
+ oidcpy(oid, &o->oid);
+ 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_oid_oneline(prefix, oid, list);
+ free(prefix);
+ return ret;
+ }
+ return 0;
+}
+
+static int get_describe_name(const char *name, int len, struct object_id *oid)
+{
+ const char *cp;
+ unsigned flags = GET_OID_QUIETLY | GET_OID_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_oid(cp, len, oid, flags);
+ }
+ }
+ }
+ return -1;
+}
+
+static int get_oid_1(const char *name, int len, struct object_id *oid, 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, oid, num);
+ /* else if (has_suffix == '~') -- goes without saying */
+ return get_nth_ancestor(name, len1, oid, num);
+ }
+
+ ret = peel_onion(name, len, oid, lookup_flags);
+ if (!ret)
+ return 0;
+
+ ret = get_oid_basic(name, len, oid, lookup_flags);
+ if (!ret)
+ return 0;
+
+ /* It could be describe output that is "SOMETHING-gXXXX" */
+ ret = get_describe_name(name, len, oid);
+ if (!ret)
+ return 0;
+
+ return get_short_oid(name, len, oid, 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);
+ 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_oid_oneline(const char *prefix, struct object_id *oid,
+ 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))
+ continue;
+ buf = get_commit_buffer(commit, NULL);
+ p = strstr(buf, "\n\n");
+ matches = negative ^ (p && !regexec(®ex, p + 2, 0, NULL, 0));
+ unuse_commit_buffer(commit, buf);
+
+ if (matches) {
+ oidcpy(oid, &commit->object.oid);
+ found = 1;
+ break;
+ }
+ }
+ regfree(®ex);
+ free_commit_list(list);
+ for (l = backup; l; l = l->next)
+ clear_commit_marks(l->item, ONELINE_SEEN);
+ free_commit_list(backup);
+ return found ? 0 : -1;
+}
+
+struct grab_nth_branch_switch_cbdata {
+ int remaining;
+ struct strbuf buf;
+};
+
+static int grab_nth_branch_switch(struct object_id *ooid, struct object_id *noid,
+ const char *email, timestamp_t timestamp, int tz,
+ const char *message, void *cb_data)
+{
+ struct grab_nth_branch_switch_cbdata *cb = cb_data;
+ const char *match = NULL, *target = NULL;
+ size_t len;
+
+ if (skip_prefix(message, "checkout: moving from ", &match))
+ target = strstr(match, " to ");
+
+ if (!match || !target)
+ return 0;
+ if (--(cb->remaining) == 0) {
+ len = target - match;
+ strbuf_reset(&cb->buf);
+ strbuf_add(&cb->buf, match, len);
+ return 1; /* we are done */
+ }
+ return 0;
+}
+
+/*
+ * Parse @{-N} syntax, return the number of characters parsed
+ * if successful; otherwise signal an error with negative value.
+ */
+static int interpret_nth_prior_checkout(const char *name, int namelen,
+ struct strbuf *buf)
+{
+ long nth;
+ int retval;
+ struct grab_nth_branch_switch_cbdata cb;
+ const char *brace;
+ char *num_end;
+
+ if (namelen < 4)
+ return -1;
+ if (name[0] != '@' || name[1] != '{' || name[2] != '-')
+ return -1;
+ brace = memchr(name, '}', namelen);
+ if (!brace)
+ return -1;
+ nth = strtol(name + 3, &num_end, 10);
+ if (num_end != brace)
+ return -1;
+ if (nth <= 0)
+ return -1;
+ cb.remaining = nth;
+ strbuf_init(&cb.buf, 20);
+
+ retval = 0;
+ if (0 < for_each_reflog_ent_reverse("HEAD", grab_nth_branch_switch, &cb)) {
+ strbuf_reset(buf);
+ strbuf_addbuf(buf, &cb.buf);
+ retval = brace - name + 1;
+ }
+
+ strbuf_release(&cb.buf);
+ return retval;
+}
+
+int get_oid_mb(const char *name, struct object_id *oid)
+{
+ struct commit *one, *two;
+ struct commit_list *mbs;
+ struct object_id oid_tmp;
+ const char *dots;
+ int st;
+
+ dots = strstr(name, "...");
+ if (!dots)
+ return get_oid(name, oid);
+ if (dots == name)
+ st = get_oid("HEAD", &oid_tmp);
+ else {
+ struct strbuf sb;
+ strbuf_init(&sb, dots - name);
+ strbuf_add(&sb, name, dots - name);
+ st = get_oid_committish(sb.buf, &oid_tmp);
+ strbuf_release(&sb);
+ }
+ if (st)
+ return st;
+ one = lookup_commit_reference_gently(&oid_tmp, 0);
+ if (!one)
+ return -1;
+
+ if (get_oid_committish(dots[3] ? (dots + 3) : "HEAD", &oid_tmp))
+ return -1;
+ two = lookup_commit_reference_gently(&oid_tmp, 0);
+ if (!two)
+ return -1;
+ mbs = get_merge_bases(one, two);
+ if (!mbs || mbs->next)
+ st = -1;
+ else {
+ st = 0;
+ oidcpy(oid, &mbs->item->object.oid);
+ }
+ free_commit_list(mbs);
+ return st;
+}
+
+/* parse @something syntax, when 'something' is not {.*} */
+static int interpret_empty_at(const char *name, int namelen, int len, struct strbuf *buf)
+{
+ const char *next;
+
+ if (len || name[1] == '{')
+ return -1;
+
+ /* make sure it's a single @, or @@{.*}, not @foo */
+ next = memchr(name + len + 1, '@', namelen - len - 1);
+ if (next && next[1] != '{')
+ return -1;
+ if (!next)
+ next = name + namelen;
+ if (next != name + 1)
+ return -1;
+
+ strbuf_reset(buf);
+ strbuf_add(buf, "HEAD", 4);
+ return 1;
+}
+
+static int reinterpret(const char *name, int namelen, int len,
+ struct strbuf *buf, unsigned allowed)
+{
+ /* we have extra data, which might need further processing */
+ struct strbuf tmp = STRBUF_INIT;
+ int used = buf->len;
+ int ret;
+
+ strbuf_add(buf, name + len, namelen - len);
+ ret = interpret_branch_name(buf->buf, buf->len, &tmp, allowed);
+ /* that data was not interpreted, remove our cruft */
+ if (ret < 0) {
+ strbuf_setlen(buf, used);
+ return len;
+ }
+ strbuf_reset(buf);
+ strbuf_addbuf(buf, &tmp);
+ strbuf_release(&tmp);
+ /* tweak for size of {-N} versus expanded ref name */
+ return ret - used + len;
+}
+
+static void set_shortened_ref(struct strbuf *buf, const char *ref)
+{
+ char *s = shorten_unambiguous_ref(ref, 0);
+ strbuf_reset(buf);
+ strbuf_addstr(buf, s);
+ free(s);
+}
+
+static int branch_interpret_allowed(const char *refname, unsigned allowed)
+{
+ if (!allowed)
+ return 1;
+
+ if ((allowed & INTERPRET_BRANCH_LOCAL) &&
+ starts_with(refname, "refs/heads/"))
+ return 1;
+ if ((allowed & INTERPRET_BRANCH_REMOTE) &&
+ starts_with(refname, "refs/remotes/"))
+ return 1;
+
+ return 0;
+}
+
+static int interpret_branch_mark(const char *name, int namelen,
+ int at, struct strbuf *buf,
+ int (*get_mark)(const char *, int),
+ const char *(*get_data)(struct branch *,
+ struct strbuf *),
+ unsigned allowed)
+{
+ int len;
+ struct branch *branch;
+ struct strbuf err = STRBUF_INIT;
+ const char *value;
+
+ len = get_mark(name + at, namelen - at);
+ if (!len)
+ return -1;
+
+ if (memchr(name, ':', at))
+ return -1;
+
+ if (at) {
+ char *name_str = xmemdupz(name, at);
+ branch = branch_get(name_str);
+ free(name_str);
+ } else
+ branch = branch_get(NULL);
+
+ value = get_data(branch, &err);
+ if (!value)
+ die("%s", err.buf);
+
+ if (!branch_interpret_allowed(value, allowed))
+ return -1;
+
+ set_shortened_ref(buf, value);
+ return len + at;
+}
+
+int interpret_branch_name(const char *name, int namelen, struct strbuf *buf,
+ unsigned allowed)
+{
+ char *at;
+ const char *start;
+ int len;
+
+ if (!namelen)
+ namelen = strlen(name);
+
+ if (!allowed || (allowed & INTERPRET_BRANCH_LOCAL)) {
+ len = interpret_nth_prior_checkout(name, namelen, buf);
+ if (!len) {
+ return len; /* syntax Ok, not enough switches */
+ } else if (len > 0) {
+ if (len == namelen)
+ return len; /* consumed all */
+ else
+ return reinterpret(name, namelen, len, buf, allowed);
+ }
+ }
+
+ for (start = name;
+ (at = memchr(start, '@', namelen - (start - name)));
+ start = at + 1) {
+
+ if (!allowed || (allowed & INTERPRET_BRANCH_HEAD)) {
+ len = interpret_empty_at(name, namelen, at - name, buf);
+ if (len > 0)
+ return reinterpret(name, namelen, len, buf,
+ allowed);
+ }
+
+ len = interpret_branch_mark(name, namelen, at - name, buf,
+ upstream_mark, branch_get_upstream,
+ allowed);
+ if (len > 0)
+ return len;
+
+ len = interpret_branch_mark(name, namelen, at - name, buf,
+ push_mark, branch_get_push,
+ allowed);
+ if (len > 0)
+ return len;
+ }
+
+ return -1;
+}
+
+void strbuf_branchname(struct strbuf *sb, const char *name, unsigned allowed)
+{
+ int len = strlen(name);
+ int used = interpret_branch_name(name, len, sb, allowed);
+
+ if (used < 0)
+ used = 0;
+ strbuf_add(sb, name + used, len - used);
+}
+
+int strbuf_check_branch_ref(struct strbuf *sb, const char *name)
+{
+ if (startup_info->have_repository)
+ strbuf_branchname(sb, name, INTERPRET_BRANCH_LOCAL);
+ else
+ strbuf_addstr(sb, name);
+
+ /*
+ * This splice must be done even if we end up rejecting the
+ * name; builtin/branch.c::copy_or_rename_branch() still wants
+ * to see what the name expanded to so that "branch -m" can be
+ * used as a tool to correct earlier mistakes.
+ */
+ strbuf_splice(sb, 0, 0, "refs/heads/", 11);
+
+ if (*name == '-' ||
+ !strcmp(sb->buf, "refs/heads/HEAD"))
+ return -1;
+
+ return check_refname_format(sb->buf, 0);
+}
+
+/*
+ * This is like "get_oid_basic()", except it allows "object ID expressions",
+ * notably "xyz^" for "parent of xyz"
+ */
+int get_oid(const char *name, struct object_id *oid)
+{
+ struct object_context unused;
+ return get_oid_with_context(name, 0, oid, &unused);
+}
+
+
+/*
+ * Many callers know that the user meant to name a commit-ish by
+ * syntactical positions where the object name appears. Calling this
+ * function allows the machinery to disambiguate shorter-than-unique
+ * abbreviated object names between commit-ish and others.
+ *
+ * Note that this does NOT error out when the named object is not a
+ * commit-ish. It is merely to give a hint to the disambiguation
+ * machinery.
+ */
+int get_oid_committish(const char *name, struct object_id *oid)
+{
+ struct object_context unused;
+ return get_oid_with_context(name, GET_OID_COMMITTISH,
+ oid, &unused);
+}
+
+int get_oid_treeish(const char *name, struct object_id *oid)
+{
+ struct object_context unused;
+ return get_oid_with_context(name, GET_OID_TREEISH,
+ oid, &unused);
+}
+
+int get_oid_commit(const char *name, struct object_id *oid)
+{
+ struct object_context unused;
+ return get_oid_with_context(name, GET_OID_COMMIT,
+ oid, &unused);
+}
+
+int get_oid_tree(const char *name, struct object_id *oid)
+{
+ struct object_context unused;
+ return get_oid_with_context(name, GET_OID_TREE,
+ oid, &unused);
+}
+
+int get_oid_blob(const char *name, struct object_id *oid)
+{
+ struct object_context unused;
+ return get_oid_with_context(name, GET_OID_BLOB,
+ oid, &unused);
+}
+
+/* Must be called only when object_name:filename doesn't exist. */
+static void diagnose_invalid_oid_path(const char *prefix,
+ const char *filename,
+ const struct object_id *tree_oid,
+ const char *object_name,
+ int object_name_len)
+{
+ struct object_id oid;
+ unsigned mode;
+
+ if (!prefix)
+ prefix = "";
+
+ if (file_exists(filename))
+ die("Path '%s' exists on disk, but not in '%.*s'.",
+ filename, object_name_len, object_name);
+ if (is_missing_file_error(errno)) {
+ char *fullname = xstrfmt("%s%s", prefix, filename);
+
+ if (!get_tree_entry(tree_oid, fullname, &oid, &mode)) {
+ die("Path '%s' exists, but not '%s'.\n"
+ "Did you mean '%.*s:%s' aka '%.*s:./%s'?",
+ fullname,
+ filename,
+ object_name_len, object_name,
+ fullname,
+ object_name_len, object_name,
+ filename);
+ }
+ die("Path '%s' does not exist in '%.*s'",
+ filename, object_name_len, object_name);
+ }
+}
+
+/* Must be called only when :stage:filename doesn't exist. */
+static void diagnose_invalid_index_path(int stage,
+ const char *prefix,
+ const char *filename)
+{
+ const struct cache_entry *ce;
+ int pos;
+ unsigned namelen = strlen(filename);
+ struct strbuf fullname = STRBUF_INIT;
+
+ if (!prefix)
+ prefix = "";
+
+ /* Wrong stage number? */
+ pos = cache_name_pos(filename, namelen);
+ if (pos < 0)
+ pos = -pos - 1;
+ if (pos < active_nr) {
+ ce = active_cache[pos];
+ if (ce_namelen(ce) == namelen &&
+ !memcmp(ce->name, filename, namelen))
+ die("Path '%s' is in the index, but not at stage %d.\n"
+ "Did you mean ':%d:%s'?",
+ filename, stage,
+ ce_stage(ce), filename);
+ }
+
+ /* Confusion between relative and absolute filenames? */
+ strbuf_addstr(&fullname, prefix);
+ strbuf_addstr(&fullname, filename);
+ pos = cache_name_pos(fullname.buf, fullname.len);
+ if (pos < 0)
+ pos = -pos - 1;
+ if (pos < active_nr) {
+ ce = active_cache[pos];
+ if (ce_namelen(ce) == fullname.len &&
+ !memcmp(ce->name, fullname.buf, fullname.len))
+ die("Path '%s' is in the index, but not '%s'.\n"
+ "Did you mean ':%d:%s' aka ':%d:./%s'?",
+ fullname.buf, filename,
+ ce_stage(ce), fullname.buf,
+ ce_stage(ce), filename);
+ }
+
+ if (file_exists(filename))
+ die("Path '%s' exists on disk, but not in the index.", filename);
+ if (is_missing_file_error(errno))
+ die("Path '%s' does not exist (neither on disk nor in the index).",
+ filename);
+
+ strbuf_release(&fullname);
+}
+
+
+static char *resolve_relative_path(const char *rel)
+{
+ if (!starts_with(rel, "./") && !starts_with(rel, "../"))
+ return NULL;
+
+ if (!is_inside_work_tree())
+ die("relative path syntax can't be used outside working tree.");
+
+ /* die() inside prefix_path() if resolved path is outside worktree */
+ return prefix_path(startup_info->prefix,
+ startup_info->prefix ? strlen(startup_info->prefix) : 0,
+ rel);
+}
+
+static int get_oid_with_context_1(const char *name,
+ unsigned flags,
+ const char *prefix,
+ struct object_id *oid,
+ struct object_context *oc)
+{
+ int ret, bracket_depth;
+ int namelen = strlen(name);
+ const char *cp;
+ int only_to_die = flags & GET_OID_ONLY_TO_DIE;
+
+ if (only_to_die)
+ flags |= GET_OID_QUIETLY;
+
+ memset(oc, 0, sizeof(*oc));
+ oc->mode = S_IFINVALID;
+ strbuf_init(&oc->symlink_path, 0);
+ ret = get_oid_1(name, namelen, oid, flags);
+ if (!ret)
+ return ret;
+ /*
+ * sha1:path --> object name of path in ent sha1
+ * :path -> object name of absolute path in index
+ * :./path -> object name of path relative to cwd in index
+ * :[0-3]:path -> object name of path in index at stage
+ * :/foo -> recent commit matching foo
+ */
+ if (name[0] == ':') {
+ int stage = 0;
+ const struct cache_entry *ce;
+ char *new_path = NULL;
+ int pos;
+ if (!only_to_die && namelen > 2 && name[1] == '/') {
+ struct commit_list *list = NULL;
+
+ for_each_ref(handle_one_ref, &list);
++ head_ref(handle_one_ref, &list);
+ commit_list_sort_by_date(&list);
+ return get_oid_oneline(name + 2, oid, list);
+ }
+ if (namelen < 3 ||
+ name[2] != ':' ||
+ name[1] < '0' || '3' < name[1])
+ cp = name + 1;
+ else {
+ stage = name[1] - '0';
+ cp = name + 3;
+ }
+ new_path = resolve_relative_path(cp);
+ if (!new_path) {
+ namelen = namelen - (cp - name);
+ } else {
+ cp = new_path;
+ namelen = strlen(cp);
+ }
+
+ if (flags & GET_OID_RECORD_PATH)
+ oc->path = xstrdup(cp);
+
+ if (!active_cache)
+ read_cache();
+ pos = cache_name_pos(cp, namelen);
+ if (pos < 0)
+ pos = -pos - 1;
+ while (pos < active_nr) {
+ ce = active_cache[pos];
+ if (ce_namelen(ce) != namelen ||
+ memcmp(ce->name, cp, namelen))
+ break;
+ if (ce_stage(ce) == stage) {
+ oidcpy(oid, &ce->oid);
+ oc->mode = ce->ce_mode;
+ free(new_path);
+ return 0;
+ }
+ pos++;
+ }
+ if (only_to_die && name[1] && name[1] != '/')
+ diagnose_invalid_index_path(stage, prefix, cp);
+ free(new_path);
+ return -1;
+ }
+ for (cp = name, bracket_depth = 0; *cp; cp++) {
+ if (*cp == '{')
+ bracket_depth++;
+ else if (bracket_depth && *cp == '}')
+ bracket_depth--;
+ else if (!bracket_depth && *cp == ':')
+ break;
+ }
+ if (*cp == ':') {
+ struct object_id tree_oid;
+ int len = cp - name;
+ unsigned sub_flags = flags;
+
+ sub_flags &= ~GET_OID_DISAMBIGUATORS;
+ sub_flags |= GET_OID_TREEISH;
+
+ if (!get_oid_1(name, len, &tree_oid, sub_flags)) {
+ const char *filename = cp+1;
+ char *new_filename = NULL;
+
+ new_filename = resolve_relative_path(filename);
+ if (new_filename)
+ filename = new_filename;
+ if (flags & GET_OID_FOLLOW_SYMLINKS) {
+ ret = get_tree_entry_follow_symlinks(&tree_oid,
+ filename, oid, &oc->symlink_path,
+ &oc->mode);
+ } else {
+ ret = get_tree_entry(&tree_oid, filename, oid,
+ &oc->mode);
+ if (ret && only_to_die) {
+ diagnose_invalid_oid_path(prefix,
+ filename,
+ &tree_oid,
+ name, len);
+ }
+ }
+ if (flags & GET_OID_RECORD_PATH)
+ oc->path = xstrdup(filename);
+
+ free(new_filename);
+ return ret;
+ } else {
+ if (only_to_die)
+ die("Invalid object name '%.*s'.", len, name);
+ }
+ }
+ return ret;
+}
+
+/*
+ * Call this function when you know "name" given by the end user must
+ * name an object but it doesn't; the function _may_ die with a better
+ * diagnostic message than "no such object 'name'", e.g. "Path 'doc' does not
+ * exist in 'HEAD'" when given "HEAD:doc", or it may return in which case
+ * you have a chance to diagnose the error further.
+ */
+void maybe_die_on_misspelt_object_name(const char *name, const char *prefix)
+{
+ struct object_context oc;
+ struct object_id oid;
+ get_oid_with_context_1(name, GET_OID_ONLY_TO_DIE, prefix, &oid, &oc);
+}
+
+int get_oid_with_context(const char *str, unsigned flags, struct object_id *oid, struct object_context *oc)
+{
+ if (flags & GET_OID_FOLLOW_SYMLINKS && flags & GET_OID_ONLY_TO_DIE)
+ BUG("incompatible flags for get_sha1_with_context");
+ return get_oid_with_context_1(str, flags, NULL, oid, oc);
+}