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authorLinus Torvalds <torvalds@linux-foundation.org>2010-01-22 02:25:20 (GMT)
committerJunio C Hamano <gitster@pobox.com>2010-01-22 04:06:58 (GMT)
commit907a7cb51c6c44d25f4c734a46d5174363190a84 (patch)
tree437762890f02ae63b73763aa666117b6882ee068 /merge-tree.c
parenta5031214c4fe5f5d3fcf649d10769744cbc66fed (diff)
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make "git merge-tree" a built-in
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Diffstat (limited to 'merge-tree.c')
-rw-r--r--merge-tree.c362
1 files changed, 0 insertions, 362 deletions
diff --git a/merge-tree.c b/merge-tree.c
deleted file mode 100644
index 37b94d9..0000000
--- a/merge-tree.c
+++ /dev/null
@@ -1,362 +0,0 @@
-#include "cache.h"
-#include "tree-walk.h"
-#include "xdiff-interface.h"
-#include "blob.h"
-#include "exec_cmd.h"
-
-static const char merge_tree_usage[] = "git merge-tree <base-tree> <branch1> <branch2>";
-static int resolve_directories = 1;
-
-struct merge_list {
- struct merge_list *next;
- struct merge_list *link; /* other stages for this object */
-
- unsigned int stage : 2,
- flags : 30;
- unsigned int mode;
- const char *path;
- struct blob *blob;
-};
-
-static struct merge_list *merge_result, **merge_result_end = &merge_result;
-
-static void add_merge_entry(struct merge_list *entry)
-{
- *merge_result_end = entry;
- merge_result_end = &entry->next;
-}
-
-static void merge_trees(struct tree_desc t[3], const char *base);
-
-static const char *explanation(struct merge_list *entry)
-{
- switch (entry->stage) {
- case 0:
- return "merged";
- case 3:
- return "added in remote";
- case 2:
- if (entry->link)
- return "added in both";
- return "added in local";
- }
-
- /* Existed in base */
- entry = entry->link;
- if (!entry)
- return "removed in both";
-
- if (entry->link)
- return "changed in both";
-
- if (entry->stage == 3)
- return "removed in local";
- return "removed in remote";
-}
-
-extern void *merge_file(const char *, struct blob *, struct blob *, struct blob *, unsigned long *);
-
-static void *result(struct merge_list *entry, unsigned long *size)
-{
- enum object_type type;
- struct blob *base, *our, *their;
-
- if (!entry->stage)
- return read_sha1_file(entry->blob->object.sha1, &type, size);
- base = NULL;
- if (entry->stage == 1) {
- base = entry->blob;
- entry = entry->link;
- }
- our = NULL;
- if (entry && entry->stage == 2) {
- our = entry->blob;
- entry = entry->link;
- }
- their = NULL;
- if (entry)
- their = entry->blob;
- return merge_file(entry->path, base, our, their, size);
-}
-
-static void *origin(struct merge_list *entry, unsigned long *size)
-{
- enum object_type type;
- while (entry) {
- if (entry->stage == 2)
- return read_sha1_file(entry->blob->object.sha1, &type, size);
- entry = entry->link;
- }
- return NULL;
-}
-
-static int show_outf(void *priv_, mmbuffer_t *mb, int nbuf)
-{
- int i;
- for (i = 0; i < nbuf; i++)
- printf("%.*s", (int) mb[i].size, mb[i].ptr);
- return 0;
-}
-
-static void show_diff(struct merge_list *entry)
-{
- unsigned long size;
- mmfile_t src, dst;
- xpparam_t xpp;
- xdemitconf_t xecfg;
- xdemitcb_t ecb;
-
- xpp.flags = XDF_NEED_MINIMAL;
- memset(&xecfg, 0, sizeof(xecfg));
- xecfg.ctxlen = 3;
- ecb.outf = show_outf;
- ecb.priv = NULL;
-
- src.ptr = origin(entry, &size);
- if (!src.ptr)
- size = 0;
- src.size = size;
- dst.ptr = result(entry, &size);
- if (!dst.ptr)
- size = 0;
- dst.size = size;
- xdi_diff(&src, &dst, &xpp, &xecfg, &ecb);
- free(src.ptr);
- free(dst.ptr);
-}
-
-static void show_result_list(struct merge_list *entry)
-{
- printf("%s\n", explanation(entry));
- do {
- struct merge_list *link = entry->link;
- static const char *desc[4] = { "result", "base", "our", "their" };
- printf(" %-6s %o %s %s\n", desc[entry->stage], entry->mode, sha1_to_hex(entry->blob->object.sha1), entry->path);
- entry = link;
- } while (entry);
-}
-
-static void show_result(void)
-{
- struct merge_list *walk;
-
- walk = merge_result;
- while (walk) {
- show_result_list(walk);
- show_diff(walk);
- walk = walk->next;
- }
-}
-
-/* An empty entry never compares same, not even to another empty entry */
-static int same_entry(struct name_entry *a, struct name_entry *b)
-{
- return a->sha1 &&
- b->sha1 &&
- !hashcmp(a->sha1, b->sha1) &&
- a->mode == b->mode;
-}
-
-static struct merge_list *create_entry(unsigned stage, unsigned mode, const unsigned char *sha1, const char *path)
-{
- struct merge_list *res = xcalloc(1, sizeof(*res));
-
- res->stage = stage;
- res->path = path;
- res->mode = mode;
- res->blob = lookup_blob(sha1);
- return res;
-}
-
-static char *traverse_path(const struct traverse_info *info, const struct name_entry *n)
-{
- char *path = xmalloc(traverse_path_len(info, n) + 1);
- return make_traverse_path(path, info, n);
-}
-
-static void resolve(const struct traverse_info *info, struct name_entry *branch1, struct name_entry *result)
-{
- struct merge_list *orig, *final;
- const char *path;
-
- /* If it's already branch1, don't bother showing it */
- if (!branch1)
- return;
-
- path = traverse_path(info, result);
- orig = create_entry(2, branch1->mode, branch1->sha1, path);
- final = create_entry(0, result->mode, result->sha1, path);
-
- final->link = orig;
-
- add_merge_entry(final);
-}
-
-static int unresolved_directory(const struct traverse_info *info, struct name_entry n[3])
-{
- char *newbase;
- struct name_entry *p;
- struct tree_desc t[3];
- void *buf0, *buf1, *buf2;
-
- if (!resolve_directories)
- return 0;
- p = n;
- if (!p->mode) {
- p++;
- if (!p->mode)
- p++;
- }
- if (!S_ISDIR(p->mode))
- return 0;
- newbase = traverse_path(info, p);
- buf0 = fill_tree_descriptor(t+0, n[0].sha1);
- buf1 = fill_tree_descriptor(t+1, n[1].sha1);
- buf2 = fill_tree_descriptor(t+2, n[2].sha1);
- merge_trees(t, newbase);
-
- free(buf0);
- free(buf1);
- free(buf2);
- free(newbase);
- return 1;
-}
-
-
-static struct merge_list *link_entry(unsigned stage, const struct traverse_info *info, struct name_entry *n, struct merge_list *entry)
-{
- const char *path;
- struct merge_list *link;
-
- if (!n->mode)
- return entry;
- if (entry)
- path = entry->path;
- else
- path = traverse_path(info, n);
- link = create_entry(stage, n->mode, n->sha1, path);
- link->link = entry;
- return link;
-}
-
-static void unresolved(const struct traverse_info *info, struct name_entry n[3])
-{
- struct merge_list *entry = NULL;
-
- if (unresolved_directory(info, n))
- return;
-
- /*
- * Do them in reverse order so that the resulting link
- * list has the stages in order - link_entry adds new
- * links at the front.
- */
- entry = link_entry(3, info, n + 2, entry);
- entry = link_entry(2, info, n + 1, entry);
- entry = link_entry(1, info, n + 0, entry);
-
- add_merge_entry(entry);
-}
-
-/*
- * Merge two trees together (t[1] and t[2]), using a common base (t[0])
- * as the origin.
- *
- * This walks the (sorted) trees in lock-step, checking every possible
- * name. Note that directories automatically sort differently from other
- * files (see "base_name_compare"), so you'll never see file/directory
- * conflicts, because they won't ever compare the same.
- *
- * IOW, if a directory changes to a filename, it will automatically be
- * seen as the directory going away, and the filename being created.
- *
- * Think of this as a three-way diff.
- *
- * The output will be either:
- * - successful merge
- * "0 mode sha1 filename"
- * NOTE NOTE NOTE! FIXME! We really really need to walk the index
- * in parallel with this too!
- *
- * - conflict:
- * "1 mode sha1 filename"
- * "2 mode sha1 filename"
- * "3 mode sha1 filename"
- * where not all of the 1/2/3 lines may exist, of course.
- *
- * The successful merge rules are the same as for the three-way merge
- * in git-read-tree.
- */
-static int threeway_callback(int n, unsigned long mask, unsigned long dirmask, struct name_entry *entry, struct traverse_info *info)
-{
- /* Same in both? */
- if (same_entry(entry+1, entry+2)) {
- if (entry[0].sha1) {
- resolve(info, NULL, entry+1);
- return mask;
- }
- }
-
- if (same_entry(entry+0, entry+1)) {
- if (entry[2].sha1 && !S_ISDIR(entry[2].mode)) {
- resolve(info, entry+1, entry+2);
- return mask;
- }
- }
-
- if (same_entry(entry+0, entry+2)) {
- if (entry[1].sha1 && !S_ISDIR(entry[1].mode)) {
- resolve(info, NULL, entry+1);
- return mask;
- }
- }
-
- unresolved(info, entry);
- return mask;
-}
-
-static void merge_trees(struct tree_desc t[3], const char *base)
-{
- struct traverse_info info;
-
- setup_traverse_info(&info, base);
- info.fn = threeway_callback;
- traverse_trees(3, t, &info);
-}
-
-static void *get_tree_descriptor(struct tree_desc *desc, const char *rev)
-{
- unsigned char sha1[20];
- void *buf;
-
- if (get_sha1(rev, sha1))
- die("unknown rev %s", rev);
- buf = fill_tree_descriptor(desc, sha1);
- if (!buf)
- die("%s is not a tree", rev);
- return buf;
-}
-
-int main(int argc, char **argv)
-{
- struct tree_desc t[3];
- void *buf1, *buf2, *buf3;
-
- if (argc != 4)
- usage(merge_tree_usage);
-
- git_extract_argv0_path(argv[0]);
-
- setup_git_directory();
-
- buf1 = get_tree_descriptor(t+0, argv[1]);
- buf2 = get_tree_descriptor(t+1, argv[2]);
- buf3 = get_tree_descriptor(t+2, argv[3]);
- merge_trees(t, "");
- free(buf1);
- free(buf2);
- free(buf3);
-
- show_result();
- return 0;
-}