mirror of
https://github.com/git/git
synced 2024-08-28 12:09:19 +00:00
![Linus Torvalds](/assets/img/avatar_default.png)
When we make the "root" tree-walk info entry have a pathname in it, we need to have a ->prev pointer so that compare_entry will actually notice and traverse into the root. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
261 lines
5.3 KiB
C
261 lines
5.3 KiB
C
#include "cache.h"
|
|
#include "tree-walk.h"
|
|
#include "tree.h"
|
|
|
|
static const char *get_mode(const char *str, unsigned int *modep)
|
|
{
|
|
unsigned char c;
|
|
unsigned int mode = 0;
|
|
|
|
if (*str == ' ')
|
|
return NULL;
|
|
|
|
while ((c = *str++) != ' ') {
|
|
if (c < '0' || c > '7')
|
|
return NULL;
|
|
mode = (mode << 3) + (c - '0');
|
|
}
|
|
*modep = mode;
|
|
return str;
|
|
}
|
|
|
|
static void decode_tree_entry(struct tree_desc *desc, const char *buf, unsigned long size)
|
|
{
|
|
const char *path;
|
|
unsigned int mode, len;
|
|
|
|
if (size < 24 || buf[size - 21])
|
|
die("corrupt tree file");
|
|
|
|
path = get_mode(buf, &mode);
|
|
if (!path || !*path)
|
|
die("corrupt tree file");
|
|
len = strlen(path) + 1;
|
|
|
|
/* Initialize the descriptor entry */
|
|
desc->entry.path = path;
|
|
desc->entry.mode = mode;
|
|
desc->entry.sha1 = (const unsigned char *)(path + len);
|
|
}
|
|
|
|
void init_tree_desc(struct tree_desc *desc, const void *buffer, unsigned long size)
|
|
{
|
|
desc->buffer = buffer;
|
|
desc->size = size;
|
|
if (size)
|
|
decode_tree_entry(desc, buffer, size);
|
|
}
|
|
|
|
void *fill_tree_descriptor(struct tree_desc *desc, const unsigned char *sha1)
|
|
{
|
|
unsigned long size = 0;
|
|
void *buf = NULL;
|
|
|
|
if (sha1) {
|
|
buf = read_object_with_reference(sha1, tree_type, &size, NULL);
|
|
if (!buf)
|
|
die("unable to read tree %s", sha1_to_hex(sha1));
|
|
}
|
|
init_tree_desc(desc, buf, size);
|
|
return buf;
|
|
}
|
|
|
|
static int entry_compare(struct name_entry *a, struct name_entry *b)
|
|
{
|
|
return df_name_compare(
|
|
a->path, tree_entry_len(a->path, a->sha1), a->mode,
|
|
b->path, tree_entry_len(b->path, b->sha1), b->mode);
|
|
}
|
|
|
|
static void entry_clear(struct name_entry *a)
|
|
{
|
|
memset(a, 0, sizeof(*a));
|
|
}
|
|
|
|
static void entry_extract(struct tree_desc *t, struct name_entry *a)
|
|
{
|
|
*a = t->entry;
|
|
}
|
|
|
|
void update_tree_entry(struct tree_desc *desc)
|
|
{
|
|
const void *buf = desc->buffer;
|
|
const unsigned char *end = desc->entry.sha1 + 20;
|
|
unsigned long size = desc->size;
|
|
unsigned long len = end - (const unsigned char *)buf;
|
|
|
|
if (size < len)
|
|
die("corrupt tree file");
|
|
buf = end;
|
|
size -= len;
|
|
desc->buffer = buf;
|
|
desc->size = size;
|
|
if (size)
|
|
decode_tree_entry(desc, buf, size);
|
|
}
|
|
|
|
int tree_entry(struct tree_desc *desc, struct name_entry *entry)
|
|
{
|
|
if (!desc->size)
|
|
return 0;
|
|
|
|
*entry = desc->entry;
|
|
update_tree_entry(desc);
|
|
return 1;
|
|
}
|
|
|
|
void setup_traverse_info(struct traverse_info *info, const char *base)
|
|
{
|
|
int pathlen = strlen(base);
|
|
static struct traverse_info dummy;
|
|
|
|
memset(info, 0, sizeof(*info));
|
|
if (pathlen && base[pathlen-1] == '/')
|
|
pathlen--;
|
|
info->pathlen = pathlen ? pathlen + 1 : 0;
|
|
info->name.path = base;
|
|
info->name.sha1 = (void *)(base + pathlen + 1);
|
|
if (pathlen)
|
|
info->prev = &dummy;
|
|
}
|
|
|
|
char *make_traverse_path(char *path, const struct traverse_info *info, const struct name_entry *n)
|
|
{
|
|
int len = tree_entry_len(n->path, n->sha1);
|
|
int pathlen = info->pathlen;
|
|
|
|
path[pathlen + len] = 0;
|
|
for (;;) {
|
|
memcpy(path + pathlen, n->path, len);
|
|
if (!pathlen)
|
|
break;
|
|
path[--pathlen] = '/';
|
|
n = &info->name;
|
|
len = tree_entry_len(n->path, n->sha1);
|
|
info = info->prev;
|
|
pathlen -= len;
|
|
}
|
|
return path;
|
|
}
|
|
|
|
int traverse_trees(int n, struct tree_desc *t, struct traverse_info *info)
|
|
{
|
|
int ret = 0;
|
|
struct name_entry *entry = xmalloc(n*sizeof(*entry));
|
|
|
|
for (;;) {
|
|
unsigned long mask = 0;
|
|
unsigned long dirmask = 0;
|
|
int i, last;
|
|
|
|
last = -1;
|
|
for (i = 0; i < n; i++) {
|
|
if (!t[i].size)
|
|
continue;
|
|
entry_extract(t+i, entry+i);
|
|
if (last >= 0) {
|
|
int cmp = entry_compare(entry+i, entry+last);
|
|
|
|
/*
|
|
* Is the new name bigger than the old one?
|
|
* Ignore it
|
|
*/
|
|
if (cmp > 0)
|
|
continue;
|
|
/*
|
|
* Is the new name smaller than the old one?
|
|
* Ignore all old ones
|
|
*/
|
|
if (cmp < 0)
|
|
mask = 0;
|
|
}
|
|
mask |= 1ul << i;
|
|
if (S_ISDIR(entry[i].mode))
|
|
dirmask |= 1ul << i;
|
|
last = i;
|
|
}
|
|
if (!mask)
|
|
break;
|
|
dirmask &= mask;
|
|
|
|
/*
|
|
* Clear all the unused name-entries.
|
|
*/
|
|
for (i = 0; i < n; i++) {
|
|
if (mask & (1ul << i))
|
|
continue;
|
|
entry_clear(entry + i);
|
|
}
|
|
ret = info->fn(n, mask, dirmask, entry, info);
|
|
if (ret < 0)
|
|
break;
|
|
if (ret)
|
|
mask &= ret;
|
|
ret = 0;
|
|
for (i = 0; i < n; i++) {
|
|
if (mask & (1ul << i))
|
|
update_tree_entry(t + i);
|
|
}
|
|
}
|
|
free(entry);
|
|
return ret;
|
|
}
|
|
|
|
static int find_tree_entry(struct tree_desc *t, const char *name, unsigned char *result, unsigned *mode)
|
|
{
|
|
int namelen = strlen(name);
|
|
while (t->size) {
|
|
const char *entry;
|
|
const unsigned char *sha1;
|
|
int entrylen, cmp;
|
|
|
|
sha1 = tree_entry_extract(t, &entry, mode);
|
|
update_tree_entry(t);
|
|
entrylen = tree_entry_len(entry, sha1);
|
|
if (entrylen > namelen)
|
|
continue;
|
|
cmp = memcmp(name, entry, entrylen);
|
|
if (cmp > 0)
|
|
continue;
|
|
if (cmp < 0)
|
|
break;
|
|
if (entrylen == namelen) {
|
|
hashcpy(result, sha1);
|
|
return 0;
|
|
}
|
|
if (name[entrylen] != '/')
|
|
continue;
|
|
if (!S_ISDIR(*mode))
|
|
break;
|
|
if (++entrylen == namelen) {
|
|
hashcpy(result, sha1);
|
|
return 0;
|
|
}
|
|
return get_tree_entry(sha1, name + entrylen, result, mode);
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
int get_tree_entry(const unsigned char *tree_sha1, const char *name, unsigned char *sha1, unsigned *mode)
|
|
{
|
|
int retval;
|
|
void *tree;
|
|
unsigned long size;
|
|
struct tree_desc t;
|
|
unsigned char root[20];
|
|
|
|
tree = read_object_with_reference(tree_sha1, tree_type, &size, root);
|
|
if (!tree)
|
|
return -1;
|
|
|
|
if (name[0] == '\0') {
|
|
hashcpy(sha1, root);
|
|
return 0;
|
|
}
|
|
|
|
init_tree_desc(&t, tree, size);
|
|
retval = find_tree_entry(&t, name, sha1, mode);
|
|
free(tree);
|
|
return retval;
|
|
}
|