Commit 1d5cda22 authored by Wayne Davison's avatar Wayne Davison

Updated to perform a much more efficient hlink algorithm that doesn't

require any binary searching of hlink data.
parent fe70ad26
......@@ -40,6 +40,46 @@ static int hlink_compare(struct file_struct **file1, struct file_struct **file2)
static struct file_struct **hlink_list;
static int hlink_count;
#define LINKED(p1,p2) ((p1)->F_DEV == (p2)->F_DEV \
&& (p1)->F_INODE == (p2)->F_INODE)
/* Analyze the data in the hlink_list[], remove items that aren't multiply
* linked, and replace the dev+inode data with the head+next linked list. */
static void link_idev_data(void)
{
struct file_struct *head;
int from, to, start;
for (from = to = 0; from < hlink_count; from++) {
start = from;
head = hlink_list[start];
while (from < hlink_count-1
&& LINKED(hlink_list[from], hlink_list[from+1])) {
hlink_list[from]->F_HEAD = head;
hlink_list[from]->F_NEXT = hlink_list[from+1];
from++;
}
if (from > start) {
hlink_list[from]->F_HEAD = head;
hlink_list[from]->F_NEXT = NULL;
hlink_list[to++] = head;
} else {
free((char*)head->link_u.idev);
head->link_u.idev = NULL;
}
}
if (!to) {
free(hlink_list);
hlink_list = NULL;
} else {
hlink_count = to;
if (!(hlink_list = realloc_array(hlink_list,
struct file_struct *, hlink_count)))
out_of_memory("init_hard_links");
}
}
#endif
void init_hard_links(struct file_list *flist)
......@@ -56,10 +96,6 @@ void init_hard_links(struct file_list *flist)
if (!(hlink_list = new_array(struct file_struct *, flist->count)))
out_of_memory("init_hard_links");
/* we'll want to restore the memcpy when we purge the
* hlink list after the sort.
* memcpy(hlink_list, flist->files, sizeof(hlink_list[0]) * flist->count);
*/
hlink_count = 0;
for (i = 0; i < flist->count; i++) {
if (flist->files[i]->link_u.idev)
......@@ -72,88 +108,21 @@ void init_hard_links(struct file_list *flist)
if (!hlink_count) {
free(hlink_list);
hlink_list = NULL;
} else if (!(hlink_list = realloc_array(hlink_list,
struct file_struct *, hlink_count)))
out_of_memory("init_hard_links");
#endif
}
/* check if a file should be skipped because it is the same as an
earlier hard link */
int check_hard_link(struct file_struct *file)
{
#if SUPPORT_HARD_LINKS
int low = 0, high = hlink_count - 1;
int ret = 0;
if (!hlink_list || !file->link_u.idev)
return 0;
while (low != high) {
int mid = (low + high) / 2;
ret = hlink_compare(&hlink_list[mid], &file);
if (ret == 0) {
low = mid;
break;
}
if (ret > 0)
high = mid;
else
low = mid + 1;
}
/* Check if we ended up finding the file struct or not. */
if (hlink_compare(&hlink_list[low], &file) != 0)
return 0;
/* Now check if the previous item shares the current one's device
* and inode. If so, we're not the "master", so return 1. */
if (low > 0 &&
file->F_DEV == hlink_list[low - 1]->F_DEV &&
file->F_INODE == hlink_list[low - 1]->F_INODE) {
if (verbose >= 2) {
rprintf(FINFO, "check_hard_link: \"%s\" is a hard link to file %d, \"%s\"\n",
f_name(file), low-1, f_name(hlink_list[low-1]));
}
return 1;
}
} else
link_idev_data();
#endif
return 0;
}
#if SUPPORT_HARD_LINKS
static void hard_link_one(int i)
static void hard_link_one(char *hlink1, char *hlink2)
{
STRUCT_STAT st1, st2;
char *hlink2, *hlink1 = f_name(hlink_list[i - 1]);
if (link_stat(hlink1, &st1) != 0)
return;
hlink2 = f_name(hlink_list[i]);
if (link_stat(hlink2, &st2) != 0) {
if (do_link(hlink1, hlink2)) {
if (verbose > 0) {
rprintf(FINFO, "link %s => %s : %s\n",
hlink2, hlink1, strerror(errno));
}
return;
}
} else {
if (st2.st_dev == st1.st_dev && st2.st_ino == st1.st_ino)
return;
if (robust_unlink(hlink2) || do_link(hlink1, hlink2)) {
if (verbose > 0) {
rprintf(FINFO, "link %s => %s : %s\n",
hlink2, hlink1, strerror(errno));
}
return;
if (do_link(hlink1, hlink2)) {
if (verbose > 0) {
rprintf(FINFO, "link %s => %s failed: %s\n",
hlink2, hlink1, strerror(errno));
}
}
if (verbose > 0)
else if (verbose > 0)
rprintf(FINFO, "%s => %s\n", hlink2, hlink1);
}
#endif
......@@ -167,16 +136,37 @@ static void hard_link_one(int i)
void do_hard_links(void)
{
#if SUPPORT_HARD_LINKS
struct file_struct *file;
char fbuf[MAXPATHLEN];
char *hlink1, *hlink2;
STRUCT_STAT st1, st2;
int i;
if (!hlink_list)
return;
for (i = 1; i < hlink_count; i++) {
if (hlink_list[i]->basename && hlink_list[i - 1]->basename &&
hlink_list[i]->F_DEV == hlink_list[i - 1]->F_DEV &&
hlink_list[i]->F_INODE == hlink_list[i - 1]->F_INODE) {
hard_link_one(i);
for (i = 0; i < hlink_count; i++) {
file = hlink_list[i];
hlink1 = f_name_to(file, fbuf, sizeof fbuf);
if (link_stat(hlink1, &st1) != 0)
continue;
while ((file = file->F_NEXT) != NULL) {
hlink2 = f_name(file);
if (link_stat(hlink2, &st2) == 0) {
if (st2.st_dev == st1.st_dev
&& st2.st_ino == st1.st_ino)
continue;
if (robust_unlink(hlink2)) {
if (verbose > 0) {
rprintf(FINFO,
"unlink %s failed: %s\n",
full_fname(hlink2),
strerror(errno));
}
continue;
}
}
hard_link_one(hlink1, hlink2);
}
}
#endif
......
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