]> rtime.felk.cvut.cz Git - git.git/blobdiff - walker.c
Modularize commit-walker
[git.git] / walker.c
diff --git a/walker.c b/walker.c
new file mode 100644 (file)
index 0000000..5c65ea4
--- /dev/null
+++ b/walker.c
@@ -0,0 +1,318 @@
+#include "cache.h"
+#include "walker.h"
+#include "commit.h"
+#include "tree.h"
+#include "tree-walk.h"
+#include "tag.h"
+#include "blob.h"
+#include "refs.h"
+#include "strbuf.h"
+
+static unsigned char current_commit_sha1[20];
+
+void walker_say(struct walker *walker, const char *fmt, const char *hex)
+{
+       if (walker->get_verbosely)
+               fprintf(stderr, fmt, hex);
+}
+
+static void report_missing(const struct object *obj)
+{
+       char missing_hex[41];
+       strcpy(missing_hex, sha1_to_hex(obj->sha1));;
+       fprintf(stderr, "Cannot obtain needed %s %s\n",
+               obj->type ? typename(obj->type): "object", missing_hex);
+       if (!is_null_sha1(current_commit_sha1))
+               fprintf(stderr, "while processing commit %s.\n",
+                       sha1_to_hex(current_commit_sha1));
+}
+
+static int process(struct walker *walker, struct object *obj);
+
+static int process_tree(struct walker *walker, struct tree *tree)
+{
+       struct tree_desc desc;
+       struct name_entry entry;
+
+       if (parse_tree(tree))
+               return -1;
+
+       init_tree_desc(&desc, tree->buffer, tree->size);
+       while (tree_entry(&desc, &entry)) {
+               struct object *obj = NULL;
+
+               /* submodule commits are not stored in the superproject */
+               if (S_ISGITLINK(entry.mode))
+                       continue;
+               if (S_ISDIR(entry.mode)) {
+                       struct tree *tree = lookup_tree(entry.sha1);
+                       if (tree)
+                               obj = &tree->object;
+               }
+               else {
+                       struct blob *blob = lookup_blob(entry.sha1);
+                       if (blob)
+                               obj = &blob->object;
+               }
+               if (!obj || process(walker, obj))
+                       return -1;
+       }
+       free(tree->buffer);
+       tree->buffer = NULL;
+       tree->size = 0;
+       return 0;
+}
+
+#define COMPLETE       (1U << 0)
+#define SEEN           (1U << 1)
+#define TO_SCAN                (1U << 2)
+
+static struct commit_list *complete = NULL;
+
+static int process_commit(struct walker *walker, struct commit *commit)
+{
+       if (parse_commit(commit))
+               return -1;
+
+       while (complete && complete->item->date >= commit->date) {
+               pop_most_recent_commit(&complete, COMPLETE);
+       }
+
+       if (commit->object.flags & COMPLETE)
+               return 0;
+
+       hashcpy(current_commit_sha1, commit->object.sha1);
+
+       walker_say(walker, "walk %s\n", sha1_to_hex(commit->object.sha1));
+
+       if (walker->get_tree) {
+               if (process(walker, &commit->tree->object))
+                       return -1;
+               if (!walker->get_all)
+                       walker->get_tree = 0;
+       }
+       if (walker->get_history) {
+               struct commit_list *parents = commit->parents;
+               for (; parents; parents = parents->next) {
+                       if (process(walker, &parents->item->object))
+                               return -1;
+               }
+       }
+       return 0;
+}
+
+static int process_tag(struct walker *walker, struct tag *tag)
+{
+       if (parse_tag(tag))
+               return -1;
+       return process(walker, tag->tagged);
+}
+
+static struct object_list *process_queue = NULL;
+static struct object_list **process_queue_end = &process_queue;
+
+static int process_object(struct walker *walker, struct object *obj)
+{
+       if (obj->type == OBJ_COMMIT) {
+               if (process_commit(walker, (struct commit *)obj))
+                       return -1;
+               return 0;
+       }
+       if (obj->type == OBJ_TREE) {
+               if (process_tree(walker, (struct tree *)obj))
+                       return -1;
+               return 0;
+       }
+       if (obj->type == OBJ_BLOB) {
+               return 0;
+       }
+       if (obj->type == OBJ_TAG) {
+               if (process_tag(walker, (struct tag *)obj))
+                       return -1;
+               return 0;
+       }
+       return error("Unable to determine requirements "
+                    "of type %s for %s",
+                    typename(obj->type), sha1_to_hex(obj->sha1));
+}
+
+static int process(struct walker *walker, struct object *obj)
+{
+       if (obj->flags & SEEN)
+               return 0;
+       obj->flags |= SEEN;
+
+       if (has_sha1_file(obj->sha1)) {
+               /* We already have it, so we should scan it now. */
+               obj->flags |= TO_SCAN;
+       }
+       else {
+               if (obj->flags & COMPLETE)
+                       return 0;
+               walker->prefetch(walker, obj->sha1);
+       }
+
+       object_list_insert(obj, process_queue_end);
+       process_queue_end = &(*process_queue_end)->next;
+       return 0;
+}
+
+static int loop(struct walker *walker)
+{
+       struct object_list *elem;
+
+       while (process_queue) {
+               struct object *obj = process_queue->item;
+               elem = process_queue;
+               process_queue = elem->next;
+               free(elem);
+               if (!process_queue)
+                       process_queue_end = &process_queue;
+
+               /* If we are not scanning this object, we placed it in
+                * the queue because we needed to fetch it first.
+                */
+               if (! (obj->flags & TO_SCAN)) {
+                       if (walker->fetch(walker, obj->sha1)) {
+                               report_missing(obj);
+                               return -1;
+                       }
+               }
+               if (!obj->type)
+                       parse_object(obj->sha1);
+               if (process_object(walker, obj))
+                       return -1;
+       }
+       return 0;
+}
+
+static int interpret_target(struct walker *walker, char *target, unsigned char *sha1)
+{
+       if (!get_sha1_hex(target, sha1))
+               return 0;
+       if (!check_ref_format(target)) {
+               if (!walker->fetch_ref(walker, target, sha1)) {
+                       return 0;
+               }
+       }
+       return -1;
+}
+
+static int mark_complete(const char *path, const unsigned char *sha1, int flag, void *cb_data)
+{
+       struct commit *commit = lookup_commit_reference_gently(sha1, 1);
+       if (commit) {
+               commit->object.flags |= COMPLETE;
+               insert_by_date(commit, &complete);
+       }
+       return 0;
+}
+
+int walker_targets_stdin(char ***target, const char ***write_ref)
+{
+       int targets = 0, targets_alloc = 0;
+       struct strbuf buf;
+       *target = NULL; *write_ref = NULL;
+       strbuf_init(&buf);
+       while (1) {
+               char *rf_one = NULL;
+               char *tg_one;
+
+               read_line(&buf, stdin, '\n');
+               if (buf.eof)
+                       break;
+               tg_one = buf.buf;
+               rf_one = strchr(tg_one, '\t');
+               if (rf_one)
+                       *rf_one++ = 0;
+
+               if (targets >= targets_alloc) {
+                       targets_alloc = targets_alloc ? targets_alloc * 2 : 64;
+                       *target = xrealloc(*target, targets_alloc * sizeof(**target));
+                       *write_ref = xrealloc(*write_ref, targets_alloc * sizeof(**write_ref));
+               }
+               (*target)[targets] = xstrdup(tg_one);
+               (*write_ref)[targets] = rf_one ? xstrdup(rf_one) : NULL;
+               targets++;
+       }
+       return targets;
+}
+
+void walker_targets_free(int targets, char **target, const char **write_ref)
+{
+       while (targets--) {
+               free(target[targets]);
+               if (write_ref && write_ref[targets])
+                       free((char *) write_ref[targets]);
+       }
+}
+
+int walker_fetch(struct walker *walker, int targets, char **target,
+                const char **write_ref, const char *write_ref_log_details)
+{
+       struct ref_lock **lock = xcalloc(targets, sizeof(struct ref_lock *));
+       unsigned char *sha1 = xmalloc(targets * 20);
+       char *msg;
+       int ret;
+       int i;
+
+       save_commit_buffer = 0;
+       track_object_refs = 0;
+
+       for (i = 0; i < targets; i++) {
+               if (!write_ref || !write_ref[i])
+                       continue;
+
+               lock[i] = lock_ref_sha1(write_ref[i], NULL);
+               if (!lock[i]) {
+                       error("Can't lock ref %s", write_ref[i]);
+                       goto unlock_and_fail;
+               }
+       }
+
+       if (!walker->get_recover)
+               for_each_ref(mark_complete, NULL);
+
+       for (i = 0; i < targets; i++) {
+               if (interpret_target(walker, target[i], &sha1[20 * i])) {
+                       error("Could not interpret %s as something to pull", target[i]);
+                       goto unlock_and_fail;
+               }
+               if (process(walker, lookup_unknown_object(&sha1[20 * i])))
+                       goto unlock_and_fail;
+       }
+
+       if (loop(walker))
+               goto unlock_and_fail;
+
+       if (write_ref_log_details) {
+               msg = xmalloc(strlen(write_ref_log_details) + 12);
+               sprintf(msg, "fetch from %s", write_ref_log_details);
+       } else {
+               msg = NULL;
+       }
+       for (i = 0; i < targets; i++) {
+               if (!write_ref || !write_ref[i])
+                       continue;
+               ret = write_ref_sha1(lock[i], &sha1[20 * i], msg ? msg : "fetch (unknown)");
+               lock[i] = NULL;
+               if (ret)
+                       goto unlock_and_fail;
+       }
+       free(msg);
+
+       return 0;
+
+unlock_and_fail:
+       for (i = 0; i < targets; i++)
+               if (lock[i])
+                       unlock_ref(lock[i]);
+
+       return -1;
+}
+
+void walker_free(struct walker *walker)
+{
+       walker->cleanup(walker);
+       free(walker);
+}