Library function to check for unmerged index entries
[gitweb.git] / commit.c
index 17f51c245525172695e6ff6d36990464349558e0..8b8fb04d1f6107da15cb142485d80cabe7a3828e 100644 (file)
--- a/commit.c
+++ b/commit.c
@@ -1,62 +1,20 @@
 #include "cache.h"
 #include "tag.h"
 #include "commit.h"
+#include "pkt-line.h"
+#include "utf8.h"
+#include "diff.h"
+#include "revision.h"
 
 int save_commit_buffer = 1;
 
-struct sort_node
-{
-       /*
-         * the number of children of the associated commit
-         * that also occur in the list being sorted.
-         */
-       unsigned int indegree;
-
-       /*
-         * reference to original list item that we will re-use
-         * on output.
-         */
-       struct commit_list * list_item;
-
-};
-
 const char *commit_type = "commit";
 
-struct cmt_fmt_map {
-       const char *n;
-       size_t cmp_len;
-       enum cmit_fmt v;
-} cmt_fmts[] = {
-       { "raw",        1,      CMIT_FMT_RAW },
-       { "medium",     1,      CMIT_FMT_MEDIUM },
-       { "short",      1,      CMIT_FMT_SHORT },
-       { "email",      1,      CMIT_FMT_EMAIL },
-       { "full",       5,      CMIT_FMT_FULL },
-       { "fuller",     5,      CMIT_FMT_FULLER },
-       { "oneline",    1,      CMIT_FMT_ONELINE },
-};
-
-enum cmit_fmt get_commit_format(const char *arg)
-{
-       int i;
-
-       if (!arg || !*arg)
-               return CMIT_FMT_DEFAULT;
-       if (*arg == '=')
-               arg++;
-       for (i = 0; i < ARRAY_SIZE(cmt_fmts); i++) {
-               if (!strncmp(arg, cmt_fmts[i].n, cmt_fmts[i].cmp_len))
-                       return cmt_fmts[i].v;
-       }
-
-       die("invalid --pretty format: %s", arg);
-}
-
 static struct commit *check_commit(struct object *obj,
                                   const unsigned char *sha1,
                                   int quiet)
 {
-       if (obj->type != TYPE_COMMIT) {
+       if (obj->type != OBJ_COMMIT) {
                if (!quiet)
                        error("Object %s is a %s, not a commit",
                              sha1_to_hex(sha1), typename(obj->type));
@@ -83,30 +41,39 @@ struct commit *lookup_commit_reference(const unsigned char *sha1)
 struct commit *lookup_commit(const unsigned char *sha1)
 {
        struct object *obj = lookup_object(sha1);
-       if (!obj) {
-               struct commit *ret = alloc_commit_node();
-               created_object(sha1, &ret->object);
-               ret->object.type = TYPE_COMMIT;
-               return ret;
-       }
+       if (!obj)
+               return create_object(sha1, OBJ_COMMIT, alloc_commit_node());
        if (!obj->type)
-               obj->type = TYPE_COMMIT;
+               obj->type = OBJ_COMMIT;
        return check_commit(obj, sha1, 0);
 }
 
-static unsigned long parse_commit_date(const char *buf)
+static unsigned long parse_commit_date(const char *buf, const char *tail)
 {
        unsigned long date;
+       const char *dateptr;
 
+       if (buf + 6 >= tail)
+               return 0;
        if (memcmp(buf, "author", 6))
                return 0;
-       while (*buf++ != '\n')
+       while (buf < tail && *buf++ != '\n')
                /* nada */;
+       if (buf + 9 >= tail)
+               return 0;
        if (memcmp(buf, "committer", 9))
                return 0;
-       while (*buf++ != '>')
+       while (buf < tail && *buf++ != '>')
                /* nada */;
-       date = strtoul(buf, NULL, 10);
+       if (buf >= tail)
+               return 0;
+       dateptr = buf;
+       while (buf < tail && *buf++ != '\n')
+               /* nada */;
+       if (buf >= tail)
+               return 0;
+       /* dateptr < buf && buf[-1] == '\n', so strtoul will stop at buf-1 */
+       date = strtoul(dateptr, NULL, 10);
        if (date == ULONG_MAX)
                date = 0;
        return date;
@@ -123,7 +90,7 @@ static int commit_graft_pos(const unsigned char *sha1)
        while (lo < hi) {
                int mi = (lo + hi) / 2;
                struct commit_graft *graft = commit_graft[mi];
-               int cmp = memcmp(sha1, graft->sha1, 20);
+               int cmp = hashcmp(sha1, graft->sha1);
                if (!cmp)
                        return mi;
                if (cmp < 0)
@@ -137,7 +104,7 @@ static int commit_graft_pos(const unsigned char *sha1)
 int register_commit_graft(struct commit_graft *graft, int ignore_dups)
 {
        int pos = commit_graft_pos(graft->sha1);
-       
+
        if (0 <= pos) {
                if (ignore_dups)
                        free(graft);
@@ -163,14 +130,6 @@ int register_commit_graft(struct commit_graft *graft, int ignore_dups)
        return 0;
 }
 
-void free_commit_grafts(void)
-{
-       int pos = commit_graft_nr;
-       while (pos >= 0)
-               free(commit_graft[pos--]);
-       commit_graft_nr = 0;
-}
-
 struct commit_graft *read_graft_line(char *buf, int len)
 {
        /* The format is just "Commit Parent1 Parent2 ...\n" */
@@ -223,19 +182,14 @@ int read_graft_file(const char *graft_file)
 static void prepare_commit_graft(void)
 {
        static int commit_graft_prepared;
-       static char *last_graft_file;
-       char *graft_file = get_graft_file();
-
-       if (last_graft_file) {
-               if (!strcmp(graft_file, last_graft_file))
-                       return;
-               free_commit_grafts();
-       }
-       if (last_graft_file)
-               free(last_graft_file);
-       last_graft_file = strdup(graft_file);
+       char *graft_file;
 
+       if (commit_graft_prepared)
+               return;
+       graft_file = get_graft_file();
        read_graft_file(graft_file);
+       /* make sure shallows are read */
+       is_repository_shallow();
        commit_graft_prepared = 1;
 }
 
@@ -249,6 +203,39 @@ static struct commit_graft *lookup_commit_graft(const unsigned char *sha1)
        return commit_graft[pos];
 }
 
+int write_shallow_commits(int fd, int use_pack_protocol)
+{
+       int i, count = 0;
+       for (i = 0; i < commit_graft_nr; i++)
+               if (commit_graft[i]->nr_parent < 0) {
+                       const char *hex =
+                               sha1_to_hex(commit_graft[i]->sha1);
+                       count++;
+                       if (use_pack_protocol)
+                               packet_write(fd, "shallow %s", hex);
+                       else {
+                               if (write_in_full(fd, hex,  40) != 40)
+                                       break;
+                               if (write_in_full(fd, "\n", 1) != 1)
+                                       break;
+                       }
+               }
+       return count;
+}
+
+int unregister_shallow(const unsigned char *sha1)
+{
+       int pos = commit_graft_pos(sha1);
+       if (pos < 0)
+               return -1;
+       if (pos + 1 < commit_graft_nr)
+               memcpy(commit_graft + pos, commit_graft + pos + 1,
+                               sizeof(struct commit_graft *)
+                               * (commit_graft_nr - pos - 1));
+       commit_graft_nr--;
+       return 0;
+}
+
 int parse_commit_buffer(struct commit *item, void *buffer, unsigned long size)
 {
        char *tail = buffer;
@@ -262,9 +249,9 @@ int parse_commit_buffer(struct commit *item, void *buffer, unsigned long size)
                return 0;
        item->object.parsed = 1;
        tail += size;
-       if (tail <= bufptr + 5 || memcmp(bufptr, "tree ", 5))
+       if (tail <= bufptr + 46 || memcmp(bufptr, "tree ", 5) || bufptr[45] != '\n')
                return error("bogus commit object %s", sha1_to_hex(item->object.sha1));
-       if (tail <= bufptr + 45 || get_sha1_hex(bufptr + 5, parent) < 0)
+       if (get_sha1_hex(bufptr + 5, parent) < 0)
                return error("bad tree pointer in commit %s",
                             sha1_to_hex(item->object.sha1));
        item->tree = lookup_tree(parent);
@@ -301,7 +288,7 @@ int parse_commit_buffer(struct commit *item, void *buffer, unsigned long size)
                        n_refs++;
                }
        }
-       item->date = parse_commit_date(bufptr);
+       item->date = parse_commit_date(bufptr, tail);
 
        if (track_object_refs) {
                unsigned i = 0;
@@ -319,18 +306,18 @@ int parse_commit_buffer(struct commit *item, void *buffer, unsigned long size)
 
 int parse_commit(struct commit *item)
 {
-       char type[20];
+       enum object_type type;
        void *buffer;
        unsigned long size;
        int ret;
 
        if (item->object.parsed)
                return 0;
-       buffer = read_sha1_file(item->object.sha1, type, &size);
+       buffer = read_sha1_file(item->object.sha1, &type, &size);
        if (!buffer)
                return error("Could not read %s",
                             sha1_to_hex(item->object.sha1));
-       if (strcmp(type, commit_type)) {
+       if (type != OBJ_COMMIT) {
                free(buffer);
                return error("Object %s not a commit",
                             sha1_to_hex(item->object.sha1));
@@ -375,7 +362,7 @@ struct commit_list * insert_by_date(struct commit *item, struct commit_list **li
        return commit_list_insert(item, pp);
 }
 
-       
+
 void sort_by_date(struct commit_list **list)
 {
        struct commit_list *ret = NULL;
@@ -410,454 +397,289 @@ struct commit *pop_most_recent_commit(struct commit_list **list,
 
 void clear_commit_marks(struct commit *commit, unsigned int mark)
 {
-       struct commit_list *parents;
+       while (commit) {
+               struct commit_list *parents;
 
-       parents = commit->parents;
-       commit->object.flags &= ~mark;
-       while (parents) {
-               struct commit *parent = parents->item;
-               if (parent && parent->object.parsed &&
-                   (parent->object.flags & mark))
-                       clear_commit_marks(parent, mark);
-               parents = parents->next;
-       }
-}
+               if (!(mark & commit->object.flags))
+                       return;
 
-/*
- * Generic support for pretty-printing the header
- */
-static int get_one_line(const char *msg, unsigned long len)
-{
-       int ret = 0;
+               commit->object.flags &= ~mark;
 
-       while (len--) {
-               char c = *msg++;
-               if (!c)
-                       break;
-               ret++;
-               if (c == '\n')
-                       break;
-       }
-       return ret;
-}
+               parents = commit->parents;
+               if (!parents)
+                       return;
 
-static int is_rfc2047_special(char ch)
-{
-       return ((ch & 0x80) || (ch == '=') || (ch == '?') || (ch == '_'));
-}
+               while ((parents = parents->next))
+                       clear_commit_marks(parents->item, mark);
 
-static int add_rfc2047(char *buf, const char *line, int len)
-{
-       char *bp = buf;
-       int i, needquote;
-       static const char q_utf8[] = "=?utf-8?q?";
-
-       for (i = needquote = 0; !needquote && i < len; i++) {
-               unsigned ch = line[i];
-               if (ch & 0x80)
-                       needquote++;
-               if ((i + 1 < len) &&
-                   (ch == '=' && line[i+1] == '?'))
-                       needquote++;
+               commit = commit->parents->item;
        }
-       if (!needquote)
-               return sprintf(buf, "%.*s", len, line);
-
-       memcpy(bp, q_utf8, sizeof(q_utf8)-1);
-       bp += sizeof(q_utf8)-1;
-       for (i = 0; i < len; i++) {
-               unsigned ch = line[i] & 0xFF;
-               if (is_rfc2047_special(ch)) {
-                       sprintf(bp, "=%02X", ch);
-                       bp += 3;
-               }
-               else if (ch == ' ')
-                       *bp++ = '_';
-               else
-                       *bp++ = ch;
-       }
-       memcpy(bp, "?=", 2);
-       bp += 2;
-       return bp - buf;
 }
 
-static int add_user_info(const char *what, enum cmit_fmt fmt, char *buf, const char *line)
+struct commit *pop_commit(struct commit_list **stack)
 {
-       char *date;
-       int namelen;
-       unsigned long time;
-       int tz, ret;
-       const char *filler = "    ";
+       struct commit_list *top = *stack;
+       struct commit *item = top ? top->item : NULL;
 
-       if (fmt == CMIT_FMT_ONELINE)
-               return 0;
-       date = strchr(line, '>');
-       if (!date)
-               return 0;
-       namelen = ++date - line;
-       time = strtoul(date, &date, 10);
-       tz = strtol(date, NULL, 10);
-
-       if (fmt == CMIT_FMT_EMAIL) {
-               char *name_tail = strchr(line, '<');
-               int display_name_length;
-               if (!name_tail)
-                       return 0;
-               while (line < name_tail && isspace(name_tail[-1]))
-                       name_tail--;
-               display_name_length = name_tail - line;
-               filler = "";
-               strcpy(buf, "From: ");
-               ret = strlen(buf);
-               ret += add_rfc2047(buf + ret, line, display_name_length);
-               memcpy(buf + ret, name_tail, namelen - display_name_length);
-               ret += namelen - display_name_length;
-               buf[ret++] = '\n';
-       }
-       else {
-               ret = sprintf(buf, "%s: %.*s%.*s\n", what,
-                             (fmt == CMIT_FMT_FULLER) ? 4 : 0,
-                             filler, namelen, line);
-       }
-       switch (fmt) {
-       case CMIT_FMT_MEDIUM:
-               ret += sprintf(buf + ret, "Date:   %s\n", show_date(time, tz));
-               break;
-       case CMIT_FMT_EMAIL:
-               ret += sprintf(buf + ret, "Date: %s\n",
-                              show_rfc2822_date(time, tz));
-               break;
-       case CMIT_FMT_FULLER:
-               ret += sprintf(buf + ret, "%sDate: %s\n", what, show_date(time, tz));
-               break;
-       default:
-               /* notin' */
-               break;
+       if (top) {
+               *stack = top->next;
+               free(top);
        }
-       return ret;
-}
-
-static int is_empty_line(const char *line, int *len_p)
-{
-       int len = *len_p;
-       while (len && isspace(line[len-1]))
-               len--;
-       *len_p = len;
-       return !len;
+       return item;
 }
 
-static int add_merge_info(enum cmit_fmt fmt, char *buf, const struct commit *commit, int abbrev)
+/*
+ * Performs an in-place topological sort on the list supplied.
+ */
+void sort_in_topological_order(struct commit_list ** list, int lifo)
 {
-       struct commit_list *parent = commit->parents;
-       int offset;
+       struct commit_list *next, *orig = *list;
+       struct commit_list *work, **insert;
+       struct commit_list **pptr;
 
-       if ((fmt == CMIT_FMT_ONELINE) || (fmt == CMIT_FMT_EMAIL) ||
-           !parent || !parent->next)
-               return 0;
+       if (!orig)
+               return;
+       *list = NULL;
 
-       offset = sprintf(buf, "Merge:");
+       /* Mark them and clear the indegree */
+       for (next = orig; next; next = next->next) {
+               struct commit *commit = next->item;
+               commit->object.flags |= TOPOSORT;
+               commit->indegree = 0;
+       }
 
-       while (parent) {
-               struct commit *p = parent->item;
-               const char *hex = abbrev
-                       ? find_unique_abbrev(p->object.sha1, abbrev)
-                       : sha1_to_hex(p->object.sha1);
-               const char *dots = (abbrev && strlen(hex) != 40) ? "..." : "";
-               parent = parent->next;
+       /* update the indegree */
+       for (next = orig; next; next = next->next) {
+               struct commit_list * parents = next->item->parents;
+               while (parents) {
+                       struct commit *parent = parents->item;
 
-               offset += sprintf(buf + offset, " %s%s", hex, dots);
+                       if (parent->object.flags & TOPOSORT)
+                               parent->indegree++;
+                       parents = parents->next;
+               }
        }
-       buf[offset++] = '\n';
-       return offset;
-}
 
-unsigned long pretty_print_commit(enum cmit_fmt fmt, const struct commit *commit, unsigned long len, char *buf, unsigned long space, int abbrev, const char *subject, const char *after_subject)
-{
-       int hdr = 1, body = 0;
-       unsigned long offset = 0;
-       int indent = 4;
-       int parents_shown = 0;
-       const char *msg = commit->buffer;
-       int plain_non_ascii = 0;
-
-       if (fmt == CMIT_FMT_ONELINE || fmt == CMIT_FMT_EMAIL)
-               indent = 0;
-
-       /* After-subject is used to pass in Content-Type: multipart
-        * MIME header; in that case we do not have to do the
-        * plaintext content type even if the commit message has
-        * non 7-bit ASCII character.  Otherwise, check if we need
-        * to say this is not a 7-bit ASCII.
+       /*
+        * find the tips
+        *
+        * tips are nodes not reachable from any other node in the list
+        *
+        * the tips serve as a starting set for the work queue.
         */
-       if (fmt == CMIT_FMT_EMAIL && !after_subject) {
-               int i, ch, in_body;
-
-               for (in_body = i = 0; (ch = msg[i]) && i < len; i++) {
-                       if (!in_body) {
-                               /* author could be non 7-bit ASCII but
-                                * the log may so; skip over the
-                                * header part first.
-                                */
-                               if (ch == '\n' &&
-                                   i + 1 < len && msg[i+1] == '\n')
-                                       in_body = 1;
-                       }
-                       else if (ch & 0x80) {
-                               plain_non_ascii = 1;
-                               break;
-                       }
-               }
+       work = NULL;
+       insert = &work;
+       for (next = orig; next; next = next->next) {
+               struct commit *commit = next->item;
+
+               if (!commit->indegree)
+                       insert = &commit_list_insert(commit, insert)->next;
        }
 
-       for (;;) {
-               const char *line = msg;
-               int linelen = get_one_line(msg, len);
+       /* process the list in topological order */
+       if (!lifo)
+               sort_by_date(&work);
 
-               if (!linelen)
-                       break;
+       pptr = list;
+       *list = NULL;
+       while (work) {
+               struct commit *commit;
+               struct commit_list *parents, *work_item;
 
-               /*
-                * We want some slop for indentation and a possible
-                * final "...". Thus the "+ 20".
-                */
-               if (offset + linelen + 20 > space) {
-                       memcpy(buf + offset, "    ...\n", 8);
-                       offset += 8;
-                       break;
-               }
+               work_item = work;
+               work = work_item->next;
+               work_item->next = NULL;
 
-               msg += linelen;
-               len -= linelen;
-               if (hdr) {
-                       if (linelen == 1) {
-                               hdr = 0;
-                               if ((fmt != CMIT_FMT_ONELINE) && !subject)
-                                       buf[offset++] = '\n';
-                               continue;
-                       }
-                       if (fmt == CMIT_FMT_RAW) {
-                               memcpy(buf + offset, line, linelen);
-                               offset += linelen;
-                               continue;
-                       }
-                       if (!memcmp(line, "parent ", 7)) {
-                               if (linelen != 48)
-                                       die("bad parent line in commit");
-                               continue;
-                       }
+               commit = work_item->item;
+               for (parents = commit->parents; parents ; parents = parents->next) {
+                       struct commit *parent=parents->item;
 
-                       if (!parents_shown) {
-                               offset += add_merge_info(fmt, buf + offset,
-                                                        commit, abbrev);
-                               parents_shown = 1;
+                       if (!(parent->object.flags & TOPOSORT))
                                continue;
-                       }
+
                        /*
-                        * MEDIUM == DEFAULT shows only author with dates.
-                        * FULL shows both authors but not dates.
-                        * FULLER shows both authors and dates.
+                        * parents are only enqueued for emission
+                        * when all their children have been emitted thereby
+                        * guaranteeing topological order.
                         */
-                       if (!memcmp(line, "author ", 7))
-                               offset += add_user_info("Author", fmt,
-                                                       buf + offset,
-                                                       line + 7);
-                       if (!memcmp(line, "committer ", 10) &&
-                           (fmt == CMIT_FMT_FULL || fmt == CMIT_FMT_FULLER))
-                               offset += add_user_info("Commit", fmt,
-                                                       buf + offset,
-                                                       line + 10);
-                       continue;
-               }
-
-               if (is_empty_line(line, &linelen)) {
-                       if (!body)
-                               continue;
-                       if (subject)
-                               continue;
-                       if (fmt == CMIT_FMT_SHORT)
-                               break;
-               } else {
-                       body = 1;
-               }
-
-               if (subject) {
-                       int slen = strlen(subject);
-                       memcpy(buf + offset, subject, slen);
-                       offset += slen;
-                       offset += add_rfc2047(buf + offset, line, linelen);
-               }
-               else {
-                       memset(buf + offset, ' ', indent);
-                       memcpy(buf + offset + indent, line, linelen);
-                       offset += linelen + indent;
-               }
-               buf[offset++] = '\n';
-               if (fmt == CMIT_FMT_ONELINE)
-                       break;
-               if (subject && plain_non_ascii) {
-                       static const char header[] =
-                               "Content-Type: text/plain; charset=UTF-8\n"
-                               "Content-Transfer-Encoding: 8bit\n";
-                       memcpy(buf + offset, header, sizeof(header)-1);
-                       offset += sizeof(header)-1;
-               }
-               if (after_subject) {
-                       int slen = strlen(after_subject);
-                       if (slen > space - offset - 1)
-                               slen = space - offset - 1;
-                       memcpy(buf + offset, after_subject, slen);
-                       offset += slen;
-                       after_subject = NULL;
+                       if (!--parent->indegree) {
+                               if (!lifo)
+                                       insert_by_date(parent, &work);
+                               else
+                                       commit_list_insert(parent, &work);
+                       }
                }
-               subject = NULL;
+               /*
+                * work_item is a commit all of whose children
+                * have already been emitted. we can emit it now.
+                */
+               commit->object.flags &= ~TOPOSORT;
+               *pptr = work_item;
+               pptr = &work_item->next;
        }
-       while (offset && isspace(buf[offset-1]))
-               offset--;
-       /* Make sure there is an EOLN for the non-oneline case */
-       if (fmt != CMIT_FMT_ONELINE)
-               buf[offset++] = '\n';
-       buf[offset] = '\0';
-       return offset;
 }
 
-struct commit *pop_commit(struct commit_list **stack)
-{
-       struct commit_list *top = *stack;
-       struct commit *item = top ? top->item : NULL;
+/* merge-base stuff */
 
-       if (top) {
-               *stack = top->next;
-               free(top);
-       }
-       return item;
-}
+/* bits #0..15 in revision.h */
+#define PARENT1                (1u<<16)
+#define PARENT2                (1u<<17)
+#define STALE          (1u<<18)
+#define RESULT         (1u<<19)
 
-int count_parents(struct commit * commit)
-{
-        int count = 0;
-        struct commit_list * parents = commit->parents;
-        for (count=0;parents; parents=parents->next,count++)
-          ;
-        return count;
-}
+static const unsigned all_flags = (PARENT1 | PARENT2 | STALE | RESULT);
 
-void topo_sort_default_setter(struct commit *c, void *data)
+static struct commit *interesting(struct commit_list *list)
 {
-       c->util = data;
+       while (list) {
+               struct commit *commit = list->item;
+               list = list->next;
+               if (commit->object.flags & STALE)
+                       continue;
+               return commit;
+       }
+       return NULL;
 }
 
-void *topo_sort_default_getter(struct commit *c)
+static struct commit_list *merge_bases(struct commit *one, struct commit *two)
 {
-       return c->util;
-}
+       struct commit_list *list = NULL;
+       struct commit_list *result = NULL;
 
-/*
- * Performs an in-place topological sort on the list supplied.
- */
-void sort_in_topological_order(struct commit_list ** list, int lifo)
-{
-       sort_in_topological_order_fn(list, lifo, topo_sort_default_setter,
-                                    topo_sort_default_getter);
-}
-
-void sort_in_topological_order_fn(struct commit_list ** list, int lifo,
-                                 topo_sort_set_fn_t setter,
-                                 topo_sort_get_fn_t getter)
-{
-       struct commit_list * next = *list;
-       struct commit_list * work = NULL, **insert;
-       struct commit_list ** pptr = list;
-       struct sort_node * nodes;
-       struct sort_node * next_nodes;
-       int count = 0;
-
-       /* determine the size of the list */
-       while (next) {
-               next = next->next;
-               count++;
-       }
-       
-       if (!count)
-               return;
-       /* allocate an array to help sort the list */
-       nodes = xcalloc(count, sizeof(*nodes));
-       /* link the list to the array */
-       next_nodes = nodes;
-       next=*list;
-       while (next) {
-               next_nodes->list_item = next;
-               setter(next->item, next_nodes);
-               next_nodes++;
-               next = next->next;
-       }
-       /* update the indegree */
-       next=*list;
-       while (next) {
-               struct commit_list * parents = next->item->parents;
+       if (one == two)
+               /* We do not mark this even with RESULT so we do not
+                * have to clean it up.
+                */
+               return commit_list_insert(one, &result);
+
+       parse_commit(one);
+       parse_commit(two);
+
+       one->object.flags |= PARENT1;
+       two->object.flags |= PARENT2;
+       insert_by_date(one, &list);
+       insert_by_date(two, &list);
+
+       while (interesting(list)) {
+               struct commit *commit;
+               struct commit_list *parents;
+               struct commit_list *n;
+               int flags;
+
+               commit = list->item;
+               n = list->next;
+               free(list);
+               list = n;
+
+               flags = commit->object.flags & (PARENT1 | PARENT2 | STALE);
+               if (flags == (PARENT1 | PARENT2)) {
+                       if (!(commit->object.flags & RESULT)) {
+                               commit->object.flags |= RESULT;
+                               insert_by_date(commit, &result);
+                       }
+                       /* Mark parents of a found merge stale */
+                       flags |= STALE;
+               }
+               parents = commit->parents;
                while (parents) {
-                       struct commit * parent=parents->item;
-                       struct sort_node * pn = (struct sort_node *) getter(parent);
+                       struct commit *p = parents->item;
+                       parents = parents->next;
+                       if ((p->object.flags & flags) == flags)
+                               continue;
+                       parse_commit(p);
+                       p->object.flags |= flags;
+                       insert_by_date(p, &list);
+               }
+       }
 
-                       if (pn)
-                               pn->indegree++;
-                       parents=parents->next;
+       /* Clean up the result to remove stale ones */
+       free_commit_list(list);
+       list = result; result = NULL;
+       while (list) {
+               struct commit_list *n = list->next;
+               if (!(list->item->object.flags & STALE))
+                       insert_by_date(list->item, &result);
+               free(list);
+               list = n;
+       }
+       return result;
+}
+
+struct commit_list *get_merge_bases(struct commit *one,
+                                       struct commit *two, int cleanup)
+{
+       struct commit_list *list;
+       struct commit **rslt;
+       struct commit_list *result;
+       int cnt, i, j;
+
+       result = merge_bases(one, two);
+       if (one == two)
+               return result;
+       if (!result || !result->next) {
+               if (cleanup) {
+                       clear_commit_marks(one, all_flags);
+                       clear_commit_marks(two, all_flags);
                }
-               next=next->next;
+               return result;
        }
-       /* 
-         * find the tips
-         *
-         * tips are nodes not reachable from any other node in the list 
-         * 
-         * the tips serve as a starting set for the work queue.
-         */
-       next=*list;
-       insert = &work;
-       while (next) {
-               struct sort_node * node = (struct sort_node *) getter(next->item);
 
-               if (node->indegree == 0) {
-                       insert = &commit_list_insert(next->item, insert)->next;
+       /* There are more than one */
+       cnt = 0;
+       list = result;
+       while (list) {
+               list = list->next;
+               cnt++;
+       }
+       rslt = xcalloc(cnt, sizeof(*rslt));
+       for (list = result, i = 0; list; list = list->next)
+               rslt[i++] = list->item;
+       free_commit_list(result);
+
+       clear_commit_marks(one, all_flags);
+       clear_commit_marks(two, all_flags);
+       for (i = 0; i < cnt - 1; i++) {
+               for (j = i+1; j < cnt; j++) {
+                       if (!rslt[i] || !rslt[j])
+                               continue;
+                       result = merge_bases(rslt[i], rslt[j]);
+                       clear_commit_marks(rslt[i], all_flags);
+                       clear_commit_marks(rslt[j], all_flags);
+                       for (list = result; list; list = list->next) {
+                               if (rslt[i] == list->item)
+                                       rslt[i] = NULL;
+                               if (rslt[j] == list->item)
+                                       rslt[j] = NULL;
+                       }
                }
-               next=next->next;
        }
 
-       /* process the list in topological order */
-       if (!lifo)
-               sort_by_date(&work);
-       while (work) {
-               struct commit * work_item = pop_commit(&work);
-               struct sort_node * work_node = (struct sort_node *) getter(work_item);
-               struct commit_list * parents = work_item->parents;
+       /* Surviving ones in rslt[] are the independent results */
+       result = NULL;
+       for (i = 0; i < cnt; i++) {
+               if (rslt[i])
+                       insert_by_date(rslt[i], &result);
+       }
+       free(rslt);
+       return result;
+}
 
-               while (parents) {
-                       struct commit * parent=parents->item;
-                       struct sort_node * pn = (struct sort_node *) getter(parent);
-
-                       if (pn) {
-                               /*
-                                * parents are only enqueued for emission 
-                                 * when all their children have been emitted thereby
-                                 * guaranteeing topological order.
-                                 */
-                               pn->indegree--;
-                               if (!pn->indegree) {
-                                       if (!lifo)
-                                               insert_by_date(parent, &work);
-                                       else
-                                               commit_list_insert(parent, &work);
-                               }
-                       }
-                       parents=parents->next;
+int in_merge_bases(struct commit *commit, struct commit **reference, int num)
+{
+       struct commit_list *bases, *b;
+       int ret = 0;
+
+       if (num == 1)
+               bases = get_merge_bases(commit, *reference, 1);
+       else
+               die("not yet");
+       for (b = bases; b; b = b->next) {
+               if (!hashcmp(commit->object.sha1, b->item->object.sha1)) {
+                       ret = 1;
+                       break;
                }
-               /*
-                 * work_item is a commit all of whose children
-                 * have already been emitted. we can emit it now.
-                 */
-               *pptr = work_node->list_item;
-               pptr = &(*pptr)->next;
-               *pptr = NULL;
-               setter(work_item, NULL);
        }
-       free(nodes);
+
+       free_commit_list(bases);
+       return ret;
 }