Merge http://www.kernel.org/pub/scm/gitk/gitk
[git] / ls-tree.c
1 /*
2  * GIT - The information manager from hell
3  *
4  * Copyright (C) Linus Torvalds, 2005
5  */
6 #include "cache.h"
7 #include "blob.h"
8 #include "tree.h"
9 #include "quote.h"
10
11 static int line_termination = '\n';
12 #define LS_RECURSIVE 1
13 #define LS_TREE_ONLY 2
14 static int ls_options = 0;
15
16 static struct tree_entry_list root_entry;
17
18 static void prepare_root(unsigned char *sha1)
19 {
20         unsigned char rsha[20];
21         unsigned long size;
22         void *buf;
23         struct tree *root_tree;
24
25         buf = read_object_with_reference(sha1, "tree", &size, rsha);
26         free(buf);
27         if (!buf)
28                 die("Could not read %s", sha1_to_hex(sha1));
29
30         root_tree = lookup_tree(rsha);
31         if (!root_tree)
32                 die("Could not read %s", sha1_to_hex(sha1));
33
34         /* Prepare a fake entry */
35         root_entry.directory = 1;
36         root_entry.executable = root_entry.symlink = 0;
37         root_entry.mode = S_IFDIR;
38         root_entry.name = "";
39         root_entry.item.tree = root_tree;
40         root_entry.parent = NULL;
41 }
42
43 static int prepare_children(struct tree_entry_list *elem)
44 {
45         if (!elem->directory)
46                 return -1;
47         if (!elem->item.tree->object.parsed) {
48                 struct tree_entry_list *e;
49                 if (parse_tree(elem->item.tree))
50                         return -1;
51                 /* Set up the parent link */
52                 for (e = elem->item.tree->entries; e; e = e->next)
53                         e->parent = elem;
54         }
55         return 0;
56 }
57
58 static struct tree_entry_list *find_entry(const char *path, char *pathbuf)
59 {
60         const char *next, *slash;
61         int len;
62         struct tree_entry_list *elem = &root_entry, *oldelem = NULL;
63
64         *(pathbuf) = '\0';
65
66         /* Find tree element, descending from root, that
67          * corresponds to the named path, lazily expanding
68          * the tree if possible.
69          */
70
71         while (path) {
72                 /* The fact we still have path means that the caller
73                  * wants us to make sure that elem at this point is a
74                  * directory, and possibly descend into it.  Even what
75                  * is left is just trailing slashes, we loop back to
76                  * here, and this call to prepare_children() will
77                  * catch elem not being a tree.  Nice.
78                  */
79                 if (prepare_children(elem))
80                         return NULL;
81
82                 slash = strchr(path, '/');
83                 if (!slash) {
84                         len = strlen(path);
85                         next = NULL;
86                 }
87                 else {
88                         next = slash + 1;
89                         len = slash - path;
90                 }
91                 if (len) {
92                         if (oldelem) {
93                                 pathbuf += sprintf(pathbuf, "%s/", oldelem->name);
94                         }
95
96                         /* (len == 0) if the original path was "drivers/char/"
97                          * and we have run already two rounds, having elem
98                          * pointing at the drivers/char directory.
99                          */
100                         elem = elem->item.tree->entries;
101                         while (elem) {
102                                 if ((strlen(elem->name) == len) &&
103                                     !strncmp(elem->name, path, len)) {
104                                         /* found */
105                                         break;
106                                 }
107                                 elem = elem->next;
108                         }
109                         if (!elem)
110                                 return NULL;
111
112                         oldelem = elem;
113                 }
114                 path = next;
115         }
116
117         return elem;
118 }
119
120 static const char *entry_type(struct tree_entry_list *e)
121 {
122         return (e->directory ? "tree" : "blob");
123 }
124
125 static const char *entry_hex(struct tree_entry_list *e)
126 {
127         return sha1_to_hex(e->directory
128                            ? e->item.tree->object.sha1
129                            : e->item.blob->object.sha1);
130 }
131
132 /* forward declaration for mutually recursive routines */
133 static int show_entry(struct tree_entry_list *, int, char *pathbuf);
134
135 static int show_children(struct tree_entry_list *e, int level, char *pathbuf)
136 {
137         int oldlen = strlen(pathbuf);
138
139         if (e != &root_entry)
140                 sprintf(pathbuf + oldlen, "%s/", e->name);
141
142         if (prepare_children(e))
143                 die("internal error: ls-tree show_children called with non tree");
144         e = e->item.tree->entries;
145         while (e) {
146                 show_entry(e, level, pathbuf);
147                 e = e->next;
148         }
149
150         pathbuf[oldlen] = '\0';
151
152         return 0;
153 }
154
155 static int show_entry(struct tree_entry_list *e, int level, char *pathbuf)
156 {
157         int err = 0; 
158
159         if (e != &root_entry) {
160                 printf("%06o %s %s      ",
161                        e->mode, entry_type(e), entry_hex(e));
162                 write_name_quoted(pathbuf, e->name, line_termination, stdout);
163                 putchar(line_termination);
164         }
165
166         if (e->directory) {
167                 /* If this is a directory, we have the following cases:
168                  * (1) This is the top-level request (explicit path from the
169                  *     command line, or "root" if there is no command line).
170                  *  a. Without any flag.  We show direct children.  We do not 
171                  *     recurse into them.
172                  *  b. With -r.  We do recurse into children.
173                  *  c. With -d.  We do not recurse into children.
174                  * (2) We came here because our caller is either (1-a) or
175                  *     (1-b).
176                  *  a. Without any flag.  We do not show our children (which
177                  *     are grandchildren for the original request).
178                  *  b. With -r.  We continue to recurse into our children.
179                  *  c. With -d.  We should not have come here to begin with.
180                  */
181                 if (level == 0 && !(ls_options & LS_TREE_ONLY))
182                         /* case (1)-a and (1)-b */
183                         err = err | show_children(e, level+1, pathbuf);
184                 else if (level && ls_options & LS_RECURSIVE)
185                         /* case (2)-b */
186                         err = err | show_children(e, level+1, pathbuf);
187         }
188         return err;
189 }
190
191 static int list_one(const char *path)
192 {
193         int err = 0;
194         char pathbuf[MAXPATHLEN + 1];
195         struct tree_entry_list *e = find_entry(path, pathbuf);
196         if (!e) {
197                 /* traditionally ls-tree does not complain about
198                  * missing path.  We may change this later to match
199                  * what "/bin/ls -a" does, which is to complain.
200                  */
201                 return err;
202         }
203         err = err | show_entry(e, 0, pathbuf);
204         return err;
205 }
206
207 static int list(char **path)
208 {
209         int i;
210         int err = 0;
211         for (i = 0; path[i]; i++)
212                 err = err | list_one(path[i]);
213         return err;
214 }
215
216 static const char ls_tree_usage[] =
217         "git-ls-tree [-d] [-r] [-z] <tree-ish> [path...]";
218
219 int main(int argc, char **argv)
220 {
221         static char *path0[] = { "", NULL };
222         char **path;
223         unsigned char sha1[20];
224
225         while (1 < argc && argv[1][0] == '-') {
226                 switch (argv[1][1]) {
227                 case 'z':
228                         line_termination = 0;
229                         break;
230                 case 'r':
231                         ls_options |= LS_RECURSIVE;
232                         break;
233                 case 'd':
234                         ls_options |= LS_TREE_ONLY;
235                         break;
236                 default:
237                         usage(ls_tree_usage);
238                 }
239                 argc--; argv++;
240         }
241
242         if (argc < 2)
243                 usage(ls_tree_usage);
244         if (get_sha1(argv[1], sha1) < 0)
245                 usage(ls_tree_usage);
246
247         path = (argc == 2) ? path0 : (argv + 2);
248         prepare_root(sha1);
249         if (list(path) < 0)
250                 die("list failed");
251         return 0;
252 }