On Fri, 30 Mar 2007, Junio C Hamano wrote:
Show 7 quoted lines
> Andy Parkins <andyparkins@gmail.com> writes:
>
> > I can't see why git feels that it has to recurse the entire subtree. It
> > seems to be something to do with the gitignore stuff. Surely there is
> > no need to use a recursive search when no directories are being added?
>
> I do not think this is anything new.
Yeah, it's probably old. That said, it's still ugly.
> Patches are welcome, but applying them to 'master' needs to wait
> post 1.5.1.
Here's a patch. It passes all tests. It's not that complex. But people should double-check. ESPECIALLY the list of special characters (currently '?' '*' '\\' and '[').
Andy, does it work for you?
NOTE! It changes the "const char **pathspec" into an array of "struct path_simplify", because that way it doesn't need to check for the magic shell expansion characters over and over and over and over again, and can just do it once up-front. All the real meat of the patch is really that conversion, and somebody should double-check that I actually got all the special characters..
The way things are set up, you can now pass a "pathspec" to the "read_directory()" function. If you pass NULL, it acts exactly like it used to do (read everything). If you pass a non-NULL pointer, it will simplify it into a "these are the prefixes without any special characters", and stop any readdir() early if the path in question doesn't match any of the prefixes.
NOTE! This does *not* obviate the need for the caller to do the *exact* pathspec match later. It's a first-level filter on "read_directory()", but it does not do the full pathspec thing. Maybe it should. But in the meantime, builtin-add.c really does need to do first
read_directory(dir, .., pathspec);
if (pathspec)
prune_directory(dir, pathspec, baselen);
ie the "prune_directory()" part will do the *exact* pathspec pruning, while the "read_directory()" will use the pathspec just to do some quick high-level pruning of the directories it will recurse into.
Does this matter? I can say that:
git ls-files -o Makefile~
on the kernel took 0.110s for me before, and it now takes 0.014s. And maybe Andy's case more noticeable. Andy?
Linus
---
builtin-add.c | 2 +-
builtin-ls-files.c | 2 +-
dir.c | 96 +++++++++++++++++++++++++++++++++++++++++++++++++---
dir.h | 2 +-
wt-status.c | 2 +-
5 files changed, 95 insertions(+), 9 deletions(-)
diff --git a/builtin-add.c b/builtin-add.c
index 9fcf514..871e23f 100644
--- a/builtin-add.c
+++ b/builtin-add.c
@@ -87,7 +87,7 @@ static void fill_directory(struct dir_struct *dir, const char **pathspec)
}
/* Read the directory and prune it */
- read_directory(dir, path, base, baselen);
+ read_directory(dir, path, base, baselen, pathspec);
if (pathspec)
prune_directory(dir, pathspec, baselen);
}
diff --git a/builtin-ls-files.c b/builtin-ls-files.c
index 4e1d5af..74a6aca 100644
--- a/builtin-ls-files.c
+++ b/builtin-ls-files.c
@@ -216,7 +216,7 @@ static void show_files(struct dir_struct *dir, const char *prefix)
if (baselen)
path = base = prefix;
- read_directory(dir, path, base, baselen);
+ read_directory(dir, path, base, baselen, pathspec);
if (show_others)
show_other_files(dir);
if (show_killed)
diff --git a/dir.c b/dir.c
index b48e19d..f1cf278 100644
--- a/dir.c
+++ b/dir.c
@@ -8,6 +8,11 @@
#include "cache.h"
#include "dir.h"
+struct path_simplify {
+ int len;
+ const char *path;
+};
+
int common_prefix(const char **pathspec)
{
const char *path, *slash, *next;
@@ -293,6 +298,31 @@ static int dir_exists(const char *dirname, int len)
}
/*
+ * This is an inexact early pruning of any recursive directory
+ * reading - if the path cannot possibly be in the pathspec,
+ * return true, and we'll skip it early.
+ */
+static int simplify_away(const char *path, int pathlen, const struct path_simplify *simplify)
+{
+ if (simplify) {
+ for (;;) {
+ const char *match = simplify->path;
+ int len = simplify->len;
+
+ if (!match)
+ break;
+ if (len > pathlen)
+ len = pathlen;
+ if (!memcmp(path, match, len))
+ return 0;
+ simplify++;
+ }
+ return 1;
+ }
+ return 0;
+}
+
+/*
* Read a directory tree. We currently ignore anything but
* directories, regular files and symlinks. That's because git
* doesn't handle them at all yet. Maybe that will change some
@@ -301,7 +331,7 @@ static int dir_exists(const char *dirname, int len)
* Also, we ignore the name ".git" (even if it is not a directory).
* That likely will not change.
*/
-static int read_directory_recursive(struct dir_struct *dir, const char *path, const char *base, int baselen, int check_only)
+static int read_directory_recursive(struct dir_struct *dir, const char *path, const char *base, int baselen, int check_only, const struct path_simplify *simplify)
{
DIR *fdir = opendir(path);
int contents = 0;
@@ -324,6 +354,8 @@ static int read_directory_recursive(struct dir_struct *dir, const char *path, co
continue;
len = strlen(de->d_name);
memcpy(fullname + baselen, de->d_name, len+1);
+ if (simplify_away(fullname, baselen + len, simplify))
+ continue;
if (excluded(dir, fullname) != dir->show_ignored) {
if (!dir->show_ignored || DTYPE(de) != DT_DIR) {
continue;
@@ -350,13 +382,13 @@ static int read_directory_recursive(struct dir_struct *dir, const char *path, co
if (dir->hide_empty_directories &&
!read_directory_recursive(dir,
fullname, fullname,
- baselen + len, 1))
+ baselen + len, 1, simplify))
continue;
break;
}
contents += read_directory_recursive(dir,
- fullname, fullname, baselen + len, 0);
+ fullname, fullname, baselen + len, 0, simplify);
continue;
case DT_REG:
case DT_LNK:
@@ -386,8 +418,61 @@ static int cmp_name(const void *p1, const void *p2)
e2->name, e2->len);
}
-int read_directory(struct dir_struct *dir, const char *path, const char *base, int baselen)
+/*
+ * Return the length of the "simple" part of a path match limiter.
+ */
+static int simple_length(const char *match)
{
+ const char special[256] = {
+ [0] = 1, ['?'] = 1,
+ ['\\'] = 1, ['*'] = 1,
+ ['['] = 1
+ };
+ int len = -1;
+
+ for (;;) {
+ unsigned char c = *match++;
+ len++;
+ if (special[c])
+ return len;
+ }
+}
+
+static struct path_simplify *create_simplify(const char **pathspec)
+{
+ int nr, alloc = 0;
+ struct path_simplify *simplify = NULL;
+
+ if (!pathspec)
+ return NULL;
+
+ for (nr = 0 ; ; nr++) {
+ const char *match;
+ if (nr >= alloc) {
+ alloc = alloc_nr(alloc);
+ simplify = xrealloc(simplify, alloc * sizeof(*simplify));
+ }
+ match = *pathspec++;
+ if (!match)
+ break;
+ simplify[nr].path = match;
+ simplify[nr].len = simple_length(match);
+ }
+ simplify[nr].path = NULL;
+ simplify[nr].len = 0;
+ return simplify;
+}
+
+static void free_simplify(struct path_simplify *simplify)
+{
+ if (simplify)
+ free(simplify);
+}
+
+int read_directory(struct dir_struct *dir, const char *path, const char *base, int baselen, const char **pathspec)
+{
+ struct path_simplify *simplify = create_simplify(pathspec);
+
/*
* Make sure to do the per-directory exclude for all the
* directories leading up to our base.
@@ -414,7 +499,8 @@ int read_directory(struct dir_struct *dir, const char *path, const char *base, i
}
}
- read_directory_recursive(dir, path, base, baselen, 0);
+ read_directory_recursive(dir, path, base, baselen, 0, simplify);
+ free_simplify(simplify);
qsort(dir->entries, dir->nr, sizeof(struct dir_entry *), cmp_name);
return dir->nr;
}
diff --git a/dir.h b/dir.h
index 7233d65..33c31f2 100644
--- a/dir.h
+++ b/dir.h
@@ -48,7 +48,7 @@ extern int common_prefix(const char **pathspec);
#define MATCHED_EXACTLY 3
extern int match_pathspec(const char **pathspec, const char *name, int namelen, int prefix, char *seen);
-extern int read_directory(struct dir_struct *, const char *path, const char *base, int baselen);
+extern int read_directory(struct dir_struct *, const char *path, const char *base, int baselen, const char **pathspec);
extern int push_exclude_per_directory(struct dir_struct *, const char *, int);
extern void pop_exclude_per_directory(struct dir_struct *, int);
diff --git a/wt-status.c b/wt-status.c
index a25632b..a055990 100644
--- a/wt-status.c
+++ b/wt-status.c
@@ -260,7 +260,7 @@ static void wt_status_print_untracked(struct wt_status *s)
if (file_exists(x))
add_excludes_from_file(&dir, x);
- read_directory(&dir, ".", "", 0);
+ read_directory(&dir, ".", "", 0, NULL);
for(i = 0; i < dir.nr; i++) {
/* check for matching entry, which is unmerged; lifted from
* builtin-ls-files:show_other_files */
