git-commit-vandalism/sha1_name.c
Shawn Pearce 70e34b2dc8 Fix ref log parsing so it works properly.
The log parser was only ever matching the last log record due to
calling strtoul on "> 1136091609" rather than " 1136091609".  Also
once a match for '@' has been found after the name of the ref there
is no point in looking for another '@' within the remaining text.

Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-05-17 17:36:36 -07:00

540 lines
12 KiB
C

#include "cache.h"
#include "tag.h"
#include "commit.h"
#include "tree.h"
#include "blob.h"
#include "tree-walk.h"
#include "refs.h"
static int find_short_object_filename(int len, const char *name, unsigned char *sha1)
{
struct alternate_object_database *alt;
char hex[40];
int found = 0;
static struct alternate_object_database *fakeent;
if (!fakeent) {
const char *objdir = get_object_directory();
int objdir_len = strlen(objdir);
int entlen = objdir_len + 43;
fakeent = xmalloc(sizeof(*fakeent) + entlen);
memcpy(fakeent->base, objdir, objdir_len);
fakeent->name = fakeent->base + objdir_len + 1;
fakeent->name[-1] = '/';
}
fakeent->next = alt_odb_list;
sprintf(hex, "%.2s", name);
for (alt = fakeent; alt && found < 2; alt = alt->next) {
struct dirent *de;
DIR *dir;
sprintf(alt->name, "%.2s/", name);
dir = opendir(alt->base);
if (!dir)
continue;
while ((de = readdir(dir)) != NULL) {
if (strlen(de->d_name) != 38)
continue;
if (memcmp(de->d_name, name + 2, len - 2))
continue;
if (!found) {
memcpy(hex + 2, de->d_name, 38);
found++;
}
else if (memcmp(hex + 2, de->d_name, 38)) {
found = 2;
break;
}
}
closedir(dir);
}
if (found == 1)
return get_sha1_hex(hex, sha1) == 0;
return found;
}
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 int find_short_packed_object(int len, const unsigned char *match, unsigned char *sha1)
{
struct packed_git *p;
unsigned char found_sha1[20];
int found = 0;
prepare_packed_git();
for (p = packed_git; p && found < 2; p = p->next) {
unsigned num = num_packed_objects(p);
unsigned first = 0, last = num;
while (first < last) {
unsigned mid = (first + last) / 2;
unsigned char now[20];
int cmp;
nth_packed_object_sha1(p, mid, now);
cmp = memcmp(match, now, 20);
if (!cmp) {
first = mid;
break;
}
if (cmp > 0) {
first = mid+1;
continue;
}
last = mid;
}
if (first < num) {
unsigned char now[20], next[20];
nth_packed_object_sha1(p, first, now);
if (match_sha(len, match, now)) {
if (nth_packed_object_sha1(p, first+1, next) ||
!match_sha(len, match, next)) {
/* unique within this pack */
if (!found) {
memcpy(found_sha1, now, 20);
found++;
}
else if (memcmp(found_sha1, now, 20)) {
found = 2;
break;
}
}
else {
/* not even unique within this pack */
found = 2;
break;
}
}
}
}
if (found == 1)
memcpy(sha1, found_sha1, 20);
return found;
}
#define SHORT_NAME_NOT_FOUND (-1)
#define SHORT_NAME_AMBIGUOUS (-2)
static int find_unique_short_object(int len, char *canonical,
unsigned char *res, unsigned char *sha1)
{
int has_unpacked, has_packed;
unsigned char unpacked_sha1[20], packed_sha1[20];
has_unpacked = find_short_object_filename(len, canonical, unpacked_sha1);
has_packed = find_short_packed_object(len, res, packed_sha1);
if (!has_unpacked && !has_packed)
return SHORT_NAME_NOT_FOUND;
if (1 < has_unpacked || 1 < has_packed)
return SHORT_NAME_AMBIGUOUS;
if (has_unpacked != has_packed) {
memcpy(sha1, (has_packed ? packed_sha1 : unpacked_sha1), 20);
return 0;
}
/* Both have unique ones -- do they match? */
if (memcmp(packed_sha1, unpacked_sha1, 20))
return SHORT_NAME_AMBIGUOUS;
memcpy(sha1, packed_sha1, 20);
return 0;
}
static int get_short_sha1(const char *name, int len, unsigned char *sha1,
int quietly)
{
int i, status;
char canonical[40];
unsigned char res[20];
if (len < MINIMUM_ABBREV)
return -1;
memset(res, 0, 20);
memset(canonical, 'x', 40);
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;
canonical[i] = c;
if (!(i & 1))
val <<= 4;
res[i >> 1] |= val;
}
status = find_unique_short_object(i, canonical, res, sha1);
if (!quietly && (status == SHORT_NAME_AMBIGUOUS))
return error("short SHA1 %.*s is ambiguous.", len, canonical);
return status;
}
const char *find_unique_abbrev(const unsigned char *sha1, int len)
{
int status, is_null;
static char hex[41];
is_null = !memcmp(sha1, null_sha1, 20);
memcpy(hex, sha1_to_hex(sha1), 40);
if (len == 40)
return hex;
while (len < 40) {
unsigned char sha1_ret[20];
status = get_short_sha1(hex, len, sha1_ret, 1);
if (!status ||
(is_null && status != SHORT_NAME_AMBIGUOUS)) {
hex[len] = 0;
return hex;
}
if (status != SHORT_NAME_AMBIGUOUS)
return NULL;
len++;
}
return NULL;
}
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 int get_sha1_basic(const char *str, int len, unsigned char *sha1)
{
static const char *fmt[] = {
"%.*s",
"refs/%.*s",
"refs/tags/%.*s",
"refs/heads/%.*s",
"refs/remotes/%.*s",
"refs/remotes/%.*s/HEAD",
NULL
};
static const char *warning = "warning: refname '%.*s' is ambiguous.\n";
const char **p, *pathname;
char *real_path = NULL;
int refs_found = 0, at_mark;
unsigned long at_time = (unsigned long)-1;
unsigned char *this_result;
unsigned char sha1_from_ref[20];
if (len == 40 && !get_sha1_hex(str, sha1))
return 0;
/* At a given period of time? "@2 hours ago" */
for (at_mark = 1; at_mark < len; at_mark++) {
if (str[at_mark] == '@') {
int date_len = len - at_mark - 1;
char *date_spec = xmalloc(date_len + 1);
strncpy(date_spec, str + at_mark + 1, date_len);
date_spec[date_len] = 0;
at_time = approxidate(date_spec);
free(date_spec);
len = at_mark;
break;
}
}
/* Accept only unambiguous ref paths. */
if (ambiguous_path(str, len))
return -1;
for (p = fmt; *p; p++) {
this_result = refs_found ? sha1_from_ref : sha1;
pathname = resolve_ref(git_path(*p, len, str), this_result, 1);
if (pathname) {
if (!refs_found++)
real_path = strdup(pathname);
if (!warn_ambiguous_refs)
break;
}
}
if (!refs_found)
return -1;
if (warn_ambiguous_refs && refs_found > 1)
fprintf(stderr, warning, len, str);
if (at_time != (unsigned long)-1) {
read_ref_at(
real_path + strlen(git_path(".")) - 1,
at_time,
sha1);
}
free(real_path);
return 0;
}
static int get_sha1_1(const char *name, int len, unsigned char *sha1);
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);
struct commit *commit;
struct commit_list *p;
if (ret)
return ret;
commit = lookup_commit_reference(sha1);
if (!commit)
return -1;
if (parse_commit(commit))
return -1;
if (!idx) {
memcpy(result, commit->object.sha1, 20);
return 0;
}
p = commit->parents;
while (p) {
if (!--idx) {
memcpy(result, p->item->object.sha1, 20);
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];
int ret = get_sha1_1(name, len, sha1);
if (ret)
return ret;
while (generation--) {
struct commit *commit = lookup_commit_reference(sha1);
if (!commit || parse_commit(commit) || !commit->parents)
return -1;
memcpy(sha1, commit->parents->item->object.sha1, 20);
}
memcpy(result, sha1, 20);
return 0;
}
static int peel_onion(const char *name, int len, unsigned char *sha1)
{
unsigned char outer[20];
const char *sp;
const char *type_string = NULL;
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 (!strncmp(commit_type, sp, 6) && sp[6] == '}')
type_string = commit_type;
else if (!strncmp(tree_type, sp, 4) && sp[4] == '}')
type_string = tree_type;
else if (!strncmp(blob_type, sp, 4) && sp[4] == '}')
type_string = blob_type;
else if (sp[0] == '}')
type_string = NULL;
else
return -1;
if (get_sha1_1(name, sp - name - 2, outer))
return -1;
o = parse_object(outer);
if (!o)
return -1;
if (!type_string) {
o = deref_tag(o, name, sp - name - 2);
if (!o || (!o->parsed && !parse_object(o->sha1)))
return -1;
memcpy(sha1, o->sha1, 20);
}
else {
/* At this point, the syntax look correct, so
* if we do not get the needed object, we should
* barf.
*/
while (1) {
if (!o || (!o->parsed && !parse_object(o->sha1)))
return -1;
if (o->type == type_string) {
memcpy(sha1, o->sha1, 20);
return 0;
}
if (o->type == tag_type)
o = ((struct tag*) o)->tagged;
else if (o->type == commit_type)
o = &(((struct commit *) o)->tree->object);
else
return error("%.*s: expected %s type, but the object dereferences to %s type",
len, name, type_string,
o->type);
if (!o->parsed)
parse_object(o->sha1);
}
}
return 0;
}
static int get_sha1_1(const char *name, int len, unsigned char *sha1)
{
int ret, has_suffix;
const char *cp;
/* "name~3" is "name^^^",
* "name~" and "name~0" are name -- not "name^0"!
* "name^" is not "name^0"; it 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 (has_suffix == '^') {
if (!num && len1 == len - 1)
num = 1;
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);
if (!ret)
return 0;
ret = get_sha1_basic(name, len, sha1);
if (!ret)
return 0;
return get_short_sha1(name, len, sha1, 0);
}
/*
* This is like "get_sha1_basic()", except it allows "sha1 expressions",
* notably "xyz^" for "parent of xyz"
*/
int get_sha1(const char *name, unsigned char *sha1)
{
int ret;
unsigned unused;
int namelen = strlen(name);
const char *cp;
prepare_alt_odb();
ret = get_sha1_1(name, namelen, sha1);
if (!ret)
return ret;
/* sha1:path --> object name of path in ent sha1
* :path -> object name of path in index
* :[0-3]:path -> object name of path in index at stage
*/
if (name[0] == ':') {
int stage = 0;
struct cache_entry *ce;
int pos;
if (namelen < 3 ||
name[2] != ':' ||
name[1] < '0' || '3' < name[1])
cp = name + 1;
else {
stage = name[1] - '0';
cp = name + 3;
}
namelen = namelen - (cp - name);
if (!active_cache)
read_cache();
if (active_nr < 0)
return -1;
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) {
memcpy(sha1, ce->sha1, 20);
return 0;
}
pos++;
}
return -1;
}
cp = strchr(name, ':');
if (cp) {
unsigned char tree_sha1[20];
if (!get_sha1_1(name, cp-name, tree_sha1))
return get_tree_entry(tree_sha1, cp+1, sha1,
&unused);
}
return ret;
}