shell.c: complain on insufficient arguments.
[gitweb.git] / ls-tree.c
index 102b12555b01ca7e7855e72479b062088e9f3b29..d9f15e349cb833401eea38d21fb050b10f9678d4 100644 (file)
--- a/ls-tree.c
+++ b/ls-tree.c
  * Copyright (C) Linus Torvalds, 2005
  */
 #include "cache.h"
+#include "blob.h"
+#include "tree.h"
+#include "quote.h"
 
-static int list(unsigned char *sha1)
+static int line_termination = '\n';
+#define LS_RECURSIVE 1
+#define LS_TREE_ONLY 2
+static int ls_options = 0;
+
+static struct tree_entry_list root_entry;
+
+static void prepare_root(unsigned char *sha1)
 {
-       void *buffer;
+       unsigned char rsha[20];
        unsigned long size;
-       char type[20];
-
-       buffer = read_sha1_file(sha1, type, &size);
-       if (!buffer)
-               die("unable to read sha1 file");
-       if (strcmp(type, "tree"))
-               die("expected a 'tree' node");
-       while (size) {
-               int len = strlen(buffer)+1;
-               unsigned char *sha1 = buffer + len;
-               char *path = strchr(buffer, ' ')+1;
-               unsigned int mode;
-               unsigned char *type;
-
-               if (size < len + 20 || sscanf(buffer, "%o", &mode) != 1)
-                       die("corrupt 'tree' file");
-               buffer = sha1 + 20;
-               size -= len + 20;
-               /* XXX: We do some ugly mode heuristics here.
-                * It seems not worth it to read each file just to get this
-                * and the file size. -- pasky@ucw.cz */
-               type = S_ISDIR(mode) ? "tree" : "blob";
-               printf("%03o\t%s\t%s\t%s\n", mode, type, sha1_to_hex(sha1), path);
+       void *buf;
+       struct tree *root_tree;
+
+       buf = read_object_with_reference(sha1, "tree", &size, rsha);
+       free(buf);
+       if (!buf)
+               die("Could not read %s", sha1_to_hex(sha1));
+
+       root_tree = lookup_tree(rsha);
+       if (!root_tree)
+               die("Could not read %s", sha1_to_hex(sha1));
+
+       /* 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 struct tree_entry_list *find_entry(const char *path, char *pathbuf)
+{
+       const char *next, *slash;
+       int len;
+       struct tree_entry_list *elem = &root_entry, *oldelem = NULL;
+
+       *(pathbuf) = '\0';
+
+       /* Find tree element, descending from root, that
+        * corresponds to the named path, lazily expanding
+        * the tree if possible.
+        */
+
+       while (path) {
+               /* The fact we still have path means that the caller
+                * wants us to make sure that elem at this point is a
+                * directory, and possibly descend into it.  Even what
+                * is left is just trailing slashes, we loop back to
+                * here, and this call to prepare_children() will
+                * catch elem not being a tree.  Nice.
+                */
+               if (prepare_children(elem))
+                       return NULL;
+
+               slash = strchr(path, '/');
+               if (!slash) {
+                       len = strlen(path);
+                       next = NULL;
+               }
+               else {
+                       next = slash + 1;
+                       len = slash - path;
+               }
+               if (len) {
+                       if (oldelem) {
+                               pathbuf += sprintf(pathbuf, "%s/", oldelem->name);
+                       }
+
+                       /* (len == 0) if the original path was "drivers/char/"
+                        * and we have run already two rounds, having elem
+                        * pointing at the drivers/char directory.
+                        */
+                       elem = elem->item.tree->entries;
+                       while (elem) {
+                               if ((strlen(elem->name) == len) &&
+                                   !strncmp(elem->name, path, len)) {
+                                       /* found */
+                                       break;
+                               }
+                               elem = elem->next;
+                       }
+                       if (!elem)
+                               return NULL;
+
+                       oldelem = elem;
+               }
+               path = next;
+       }
+
+       return elem;
+}
+
+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, char *pathbuf);
+
+static int show_children(struct tree_entry_list *e, int level, char *pathbuf)
+{
+       int oldlen = strlen(pathbuf);
+
+       if (e != &root_entry)
+               sprintf(pathbuf + oldlen, "%s/", e->name);
+
+       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, pathbuf);
+               e = e->next;
+       }
+
+       pathbuf[oldlen] = '\0';
+
+       return 0;
+}
+
+static int show_entry(struct tree_entry_list *e, int level, char *pathbuf)
+{
+       int err = 0; 
+
+       if (e != &root_entry) {
+               printf("%06o %s %s      ",
+                      e->mode, entry_type(e), entry_hex(e));
+               write_name_quoted(pathbuf, e->name, line_termination, stdout);
+               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, pathbuf);
+               else if (level && ls_options & LS_RECURSIVE)
+                       /* case (2)-b */
+                       err = err | show_children(e, level+1, pathbuf);
+       }
+       return err;
+}
+
+static int list_one(const char *path)
+{
+       int err = 0;
+       char pathbuf[MAXPATHLEN + 1];
+       struct tree_entry_list *e = find_entry(path, pathbuf);
+       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, pathbuf);
+       return err;
+}
+
+static int list(char **path)
+{
+       int i;
+       int err = 0;
+       for (i = 0; path[i]; i++)
+               err = err | list_one(path[i]);
+       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];
 
-       if (argc != 2)
-               usage("ls-tree <key>");
-       if (get_sha1_hex(argv[1], sha1) < 0)
-               usage("ls-tree <key>");
-       sha1_file_directory = getenv(DB_ENVIRONMENT);
-       if (!sha1_file_directory)
-               sha1_file_directory = DEFAULT_DB_ENVIRONMENT;
-       if (list(sha1) < 0)
+       while (1 < argc && argv[1][0] == '-') {
+               switch (argv[1][1]) {
+               case 'z':
+                       line_termination = 0;
+                       break;
+               case 'r':
+                       ls_options |= LS_RECURSIVE;
+                       break;
+               case 'd':
+                       ls_options |= LS_TREE_ONLY;
+                       break;
+               default:
+                       usage(ls_tree_usage);
+               }
+               argc--; argv++;
+       }
+
+       if (argc < 2)
+               usage(ls_tree_usage);
+       if (get_sha1(argv[1], sha1) < 0)
+               usage(ls_tree_usage);
+
+       path = (argc == 2) ? path0 : (argv + 2);
+       prepare_root(sha1);
+       if (list(path) < 0)
                die("list failed");
        return 0;
 }