[PATCH] Rewrite ls-tree to behave more like "/bin/ls -a"

This is a complete rewrite of ls-tree to make it behave more
like what "/bin/ls -a" does in the current working directory.

Namely, the changes are:

 - Unlike the old ls-tree behaviour that used paths arguments to
   restrict output (not that it worked as intended---as pointed
   out in the mailing list discussion, it was quite incoherent),
   this rewrite uses paths arguments to specify what to show.

 - Without arguments, it implicitly uses the root level as its
   sole argument ("/bin/ls -a" behaves as if "." is given
   without argument).

 - Without -r (recursive) flag, it shows the named blob (either
   file or symlink), or the named tree and its immediate
   children.

 - With -r flag, it shows the named path, and recursively
   descends into it if it is a tree.

 - With -d flag, it shows the named path and does not show its
   children even if the path is a tree, nor descends into it
   recursively.

This is still request-for-comments patch.  There is no mailing
list consensus that this proposed new behaviour is a good one.

The patch to t/t3100-ls-tree-restrict.sh illustrates
user-visible behaviour changes.  Namely:

 * "git-ls-tree $tree path1 path0" lists path1 first and then
   path0.  It used to use paths as an output restrictor and
   showed output in cache entry order (i.e. path0 first and then
   path1) regardless of the order of paths arguments.

 * "git-ls-tree $tree path2" lists path2 and its immediate
   children but having explicit paths argument does not imply
   recursive behaviour anymore, hence paths/baz is shown but not
   paths/baz/b.

Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Junio C Hamano 2005-05-28 00:05:38 -07:00 committed by Linus Torvalds
parent 2bc2564145
commit 6af1f0192f
5 changed files with 219 additions and 180 deletions

View File

@ -4,23 +4,26 @@ v0.1, May 2005
NAME
----
git-ls-tree - Displays a tree object in human readable form
git-ls-tree - Lists the contents of a tree object.
SYNOPSIS
--------
'git-ls-tree' [-r] [-z] <tree-ish> [paths...]
'git-ls-tree' [-d] [-r] [-z] <tree-ish> [paths...]
DESCRIPTION
-----------
Converts the tree object to a human readable (and script processable)
form.
Lists the contents of a tree object, like what "/bin/ls -a" does
in the current working directory.
OPTIONS
-------
<tree-ish>::
Id of a tree.
-d::
show only the named tree entry itself, not its children
-r::
recurse into sub-trees
@ -28,18 +31,19 @@ OPTIONS
\0 line termination on output
paths::
Optionally, restrict the output of git-ls-tree to specific
paths. Directories will only list their tree blob ids.
Implies -r.
When paths are given, shows them. Otherwise implicitly
uses the root level of the tree as the sole path argument.
Output Format
-------------
<mode>\t <type>\t <object>\t <file>
<mode> SP <type> SP <object> TAB <file>
Author
------
Written by Linus Torvalds <torvalds@osdl.org>
Completely rewritten from scratch by Junio C Hamano <junkio@cox.net>
Documentation
--------------

373
ls-tree.c
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@ -4,188 +4,217 @@
* Copyright (C) Linus Torvalds, 2005
*/
#include "cache.h"
#include "blob.h"
#include "tree.h"
static int line_termination = '\n';
static int recursive = 0;
#define LS_RECURSIVE 1
#define LS_TREE_ONLY 2
static int ls_options = 0;
struct path_prefix {
struct path_prefix *prev;
const char *name;
};
static struct tree_entry_list root_entry;
#define DEBUG(fmt, ...)
static int string_path_prefix(char *buff, size_t blen, struct path_prefix *prefix)
static void prepare_root(unsigned char *sha1)
{
int len = 0;
if (prefix) {
if (prefix->prev) {
len = string_path_prefix(buff,blen,prefix->prev);
buff += len;
blen -= len;
if (blen > 0) {
*buff = '/';
len++;
buff++;
blen--;
}
}
strncpy(buff,prefix->name,blen);
return len + strlen(prefix->name);
}
return 0;
}
static void print_path_prefix(struct path_prefix *prefix)
{
if (prefix) {
if (prefix->prev) {
print_path_prefix(prefix->prev);
putchar('/');
}
fputs(prefix->name, stdout);
}
}
/*
* return:
* -1 if prefix is *not* a subset of path
* 0 if prefix == path
* 1 if prefix is a subset of path
*/
static int pathcmp(const char *path, struct path_prefix *prefix)
{
char buff[PATH_MAX];
int len,slen;
if (prefix == NULL)
return 1;
len = string_path_prefix(buff, sizeof buff, prefix);
slen = strlen(path);
if (slen < len)
return -1;
if (strncmp(path,buff,len) == 0) {
if (slen == len)
return 0;
else
return 1;
}
return -1;
}
/*
* match may be NULL, or a *sorted* list of paths
*/
static void list_recursive(void *buffer,
const char *type,
unsigned long size,
struct path_prefix *prefix,
char **match, int matches)
{
struct path_prefix this_prefix;
this_prefix.prev = prefix;
if (strcmp(type, "tree"))
die("expected a 'tree' node");
if (matches)
recursive = 1;
while (size) {
int namelen = strlen(buffer)+1;
void *eltbuf = NULL;
char elttype[20];
unsigned long eltsize;
unsigned char *sha1 = buffer + namelen;
char *path = strchr(buffer, ' ') + 1;
unsigned int mode;
const char *matched = NULL;
int mtype = -1;
int mindex;
if (size < namelen + 20 || sscanf(buffer, "%o", &mode) != 1)
die("corrupt 'tree' file");
buffer = sha1 + 20;
size -= namelen + 20;
this_prefix.name = path;
for ( mindex = 0; mindex < matches; mindex++) {
mtype = pathcmp(match[mindex],&this_prefix);
if (mtype >= 0) {
matched = match[mindex];
break;
}
}
/*
* If we're not matching, or if this is an exact match,
* print out the info
*/
if (!matches || (matched != NULL && mtype == 0)) {
printf("%06o %s %s\t", mode,
S_ISDIR(mode) ? "tree" : "blob",
sha1_to_hex(sha1));
print_path_prefix(&this_prefix);
putchar(line_termination);
}
if (! recursive || ! S_ISDIR(mode))
continue;
if (matches && ! matched)
continue;
if (! (eltbuf = read_sha1_file(sha1, elttype, &eltsize)) ) {
error("cannot read %s", sha1_to_hex(sha1));
continue;
}
/* If this is an exact directory match, we may have
* directory files following this path. Match on them.
* Otherwise, we're at a pach subcomponent, and we need
* to try to match again.
*/
if (mtype == 0)
mindex++;
list_recursive(eltbuf, elttype, eltsize, &this_prefix, &match[mindex], matches-mindex);
free(eltbuf);
}
}
static int qcmp(const void *a, const void *b)
{
return strcmp(*(char **)a, *(char **)b);
}
static int list(unsigned char *sha1,char **path)
{
void *buffer;
unsigned char rsha[20];
unsigned long size;
int npaths;
void *buf;
struct tree *root_tree;
for (npaths = 0; path[npaths] != NULL; npaths++)
;
buf = read_object_with_reference(sha1, "tree", &size, rsha);
free(buf);
if (!buf)
die("Could not read %s", sha1_to_hex(sha1));
qsort(path,npaths,sizeof(char *),qcmp);
root_tree = lookup_tree(rsha);
if (!root_tree)
die("Could not read %s", sha1_to_hex(sha1));
buffer = read_object_with_reference(sha1, "tree", &size, NULL);
if (!buffer)
die("unable to read sha1 file");
list_recursive(buffer, "tree", size, NULL, path, npaths);
free(buffer);
/* Prepare a fake entry */
root_entry.directory = 1;
root_entry.executable = root_entry.symlink = 0;
root_entry.mode = S_IFDIR;
root_entry.name = "";
root_entry.item.tree = root_tree;
root_entry.parent = NULL;
}
static int prepare_children(struct tree_entry_list *elem)
{
if (!elem->directory)
return -1;
if (!elem->item.tree->object.parsed) {
struct tree_entry_list *e;
if (parse_tree(elem->item.tree))
return -1;
/* Set up the parent link */
for (e = elem->item.tree->entries; e; e = e->next)
e->parent = elem;
}
return 0;
}
static const char *ls_tree_usage = "git-ls-tree [-r] [-z] <key> [paths...]";
static struct tree_entry_list *find_entry_0(struct tree_entry_list *elem,
const char *path,
const char *path_end)
{
const char *ep;
int len;
while (path < path_end) {
if (prepare_children(elem))
return NULL;
/* In elem->tree->entries, find the one that has name
* that matches what is between path and ep.
*/
elem = elem->item.tree->entries;
ep = strchr(path, '/');
if (!ep || path_end <= ep)
ep = path_end;
len = ep - path;
while (elem) {
if ((strlen(elem->name) == len) &&
!strncmp(elem->name, path, len))
break;
elem = elem->next;
}
if (path_end <= ep || !elem)
return elem;
while (*ep == '/' && ep < path_end)
ep++;
path = ep;
}
return NULL;
}
static struct tree_entry_list *find_entry(const char *path,
const char *path_end)
{
/* Find tree element, descending from root, that
* corresponds to the named path, lazily expanding
* the tree if possible.
*/
if (path == path_end) {
/* Special. This is the root level */
return &root_entry;
}
return find_entry_0(&root_entry, path, path_end);
}
static void show_entry_name(struct tree_entry_list *e)
{
/* This is yucky. The root level is there for
* our convenience but we really want to do a
* forest.
*/
if (e->parent && e->parent != &root_entry) {
show_entry_name(e->parent);
putchar('/');
}
printf("%s", e->name);
}
static const char *entry_type(struct tree_entry_list *e)
{
return (e->directory ? "tree" : "blob");
}
static const char *entry_hex(struct tree_entry_list *e)
{
return sha1_to_hex(e->directory
? e->item.tree->object.sha1
: e->item.blob->object.sha1);
}
/* forward declaration for mutually recursive routines */
static int show_entry(struct tree_entry_list *, int);
static int show_children(struct tree_entry_list *e, int level)
{
if (prepare_children(e))
die("internal error: ls-tree show_children called with non tree");
e = e->item.tree->entries;
while (e) {
show_entry(e, level);
e = e->next;
}
return 0;
}
static int show_entry(struct tree_entry_list *e, int level)
{
int err = 0;
if (e != &root_entry) {
printf("%06o %s %s ", e->mode, entry_type(e),
entry_hex(e));
show_entry_name(e);
putchar(line_termination);
}
if (e->directory) {
/* If this is a directory, we have the following cases:
* (1) This is the top-level request (explicit path from the
* command line, or "root" if there is no command line).
* a. Without any flag. We show direct children. We do not
* recurse into them.
* b. With -r. We do recurse into children.
* c. With -d. We do not recurse into children.
* (2) We came here because our caller is either (1-a) or
* (1-b).
* a. Without any flag. We do not show our children (which
* are grandchildren for the original request).
* b. With -r. We continue to recurse into our children.
* c. With -d. We should not have come here to begin with.
*/
if (level == 0 && !(ls_options & LS_TREE_ONLY))
/* case (1)-a and (1)-b */
err = err | show_children(e, level+1);
else if (level && ls_options & LS_RECURSIVE)
/* case (2)-b */
err = err | show_children(e, level+1);
}
return err;
}
static int list_one(const char *path, const char *path_end)
{
int err = 0;
struct tree_entry_list *e = find_entry(path, path_end);
if (!e) {
/* traditionally ls-tree does not complain about
* missing path. We may change this later to match
* what "/bin/ls -a" does, which is to complain.
*/
return err;
}
err = err | show_entry(e, 0);
return err;
}
static int list(char **path)
{
int i;
int err = 0;
for (i = 0; path[i]; i++) {
int len = strlen(path[i]);
while (0 <= len && path[i][len] == '/')
len--;
err = err | list_one(path[i], path[i] + len);
}
return err;
}
static const char *ls_tree_usage =
"git-ls-tree [-d] [-r] [-z] <tree-ish> [path...]";
int main(int argc, char **argv)
{
static char *path0[] = { "", NULL };
char **path;
unsigned char sha1[20];
while (1 < argc && argv[1][0] == '-') {
@ -194,7 +223,10 @@ int main(int argc, char **argv)
line_termination = 0;
break;
case 'r':
recursive = 1;
ls_options |= LS_RECURSIVE;
break;
case 'd':
ls_options |= LS_TREE_ONLY;
break;
default:
usage(ls_tree_usage);
@ -206,7 +238,10 @@ int main(int argc, char **argv)
usage(ls_tree_usage);
if (get_sha1(argv[1], sha1) < 0)
usage(ls_tree_usage);
if (list(sha1, &argv[2]) < 0)
path = (argc == 2) ? path0 : (argv + 2);
prepare_root(sha1);
if (list(path) < 0)
die("list failed");
return 0;
}

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@ -74,8 +74,8 @@ test_expect_success \
'ls-tree filtered' \
'git-ls-tree $tree path1 path0 >current &&
cat >expected <<\EOF &&
100644 blob X path0
120000 blob X path1
100644 blob X path0
EOF
test_output'
@ -85,7 +85,6 @@ test_expect_success \
cat >expected <<\EOF &&
040000 tree X path2
040000 tree X path2/baz
100644 blob X path2/baz/b
120000 blob X path2/bazbo
100644 blob X path2/foo
EOF

2
tree.c
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@ -133,7 +133,7 @@ int parse_tree_buffer(struct tree *item, void *buffer, unsigned long size)
}
if (obj)
add_ref(&item->object, obj);
entry->parent = NULL; /* needs to be filled by the user */
*list_p = entry;
list_p = &entry->next;
}

1
tree.h
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@ -16,6 +16,7 @@ struct tree_entry_list {
struct tree *tree;
struct blob *blob;
} item;
struct tree_entry_list *parent;
};
struct tree {