This rewrites `git merge-octopus' from shell to C. As for the two last conversions, this port removes calls to external processes to avoid reading and writing the index over and over again. - Calls to `read-tree -u -m (--aggressive)?' are replaced by calls to unpack_trees(). - The call to `write-tree' is replaced by a call to write_index_as_tree(). - The call to `diff-index ...' is replaced by a call to repo_index_has_changes(). - The call to `merge-index', needed to invoke `git merge-one-file', is replaced by a call to merge_all_index(). The index is read in cmd_merge_octopus(), and is wrote back by merge_strategies_octopus(). Here to, merge_strategies_octopus() takes two commit lists and a string to reduce frictions when try_merge_strategies() will be modified to call it directly. Signed-off-by: Alban Gruin <alban.gruin@xxxxxxxxx> --- Makefile | 2 +- builtin.h | 1 + builtin/merge-octopus.c | 69 ++++++++++++++++ git-merge-octopus.sh | 112 ------------------------- git.c | 1 + merge-strategies.c | 177 ++++++++++++++++++++++++++++++++++++++++ merge-strategies.h | 3 + 7 files changed, 252 insertions(+), 113 deletions(-) create mode 100644 builtin/merge-octopus.c delete mode 100755 git-merge-octopus.sh diff --git a/Makefile b/Makefile index 3cc6b192f1..2b2bdffafe 100644 --- a/Makefile +++ b/Makefile @@ -600,7 +600,6 @@ unexport CDPATH SCRIPT_SH += git-bisect.sh SCRIPT_SH += git-difftool--helper.sh SCRIPT_SH += git-filter-branch.sh -SCRIPT_SH += git-merge-octopus.sh SCRIPT_SH += git-mergetool.sh SCRIPT_SH += git-quiltimport.sh SCRIPT_SH += git-request-pull.sh @@ -1093,6 +1092,7 @@ BUILTIN_OBJS += builtin/mailsplit.o BUILTIN_OBJS += builtin/merge-base.o BUILTIN_OBJS += builtin/merge-file.o BUILTIN_OBJS += builtin/merge-index.o +BUILTIN_OBJS += builtin/merge-octopus.o BUILTIN_OBJS += builtin/merge-one-file.o BUILTIN_OBJS += builtin/merge-ours.o BUILTIN_OBJS += builtin/merge-recursive.o diff --git a/builtin.h b/builtin.h index 35e91c16d0..50225404a0 100644 --- a/builtin.h +++ b/builtin.h @@ -176,6 +176,7 @@ int cmd_maintenance(int argc, const char **argv, const char *prefix); int cmd_merge(int argc, const char **argv, const char *prefix); int cmd_merge_base(int argc, const char **argv, const char *prefix); int cmd_merge_index(int argc, const char **argv, const char *prefix); +int cmd_merge_octopus(int argc, const char **argv, const char *prefix); int cmd_merge_ours(int argc, const char **argv, const char *prefix); int cmd_merge_file(int argc, const char **argv, const char *prefix); int cmd_merge_one_file(int argc, const char **argv, const char *prefix); diff --git a/builtin/merge-octopus.c b/builtin/merge-octopus.c new file mode 100644 index 0000000000..ca8f9f345d --- /dev/null +++ b/builtin/merge-octopus.c @@ -0,0 +1,69 @@ +/* + * Builtin "git merge-octopus" + * + * Copyright (c) 2020 Alban Gruin + * + * Based on git-merge-octopus.sh, written by Junio C Hamano. + * + * Resolve two or more trees. + */ + +#define USE_THE_INDEX_COMPATIBILITY_MACROS +#include "cache.h" +#include "builtin.h" +#include "commit.h" +#include "merge-strategies.h" + +static const char builtin_merge_octopus_usage[] = + "git merge-octopus [<bases>...] -- <head> <remote1> <remote2> [<remotes>...]"; + +int cmd_merge_octopus(int argc, const char **argv, const char *prefix) +{ + int i, sep_seen = 0; + struct commit_list *bases = NULL, *remotes = NULL; + struct commit_list **next_base = &bases, **next_remote = &remotes; + const char *head_arg = NULL; + + if (argc < 5) + usage(builtin_merge_octopus_usage); + + setup_work_tree(); + if (read_cache() < 0) + die("invalid index"); + + /* + * The first parameters up to -- are merge bases; the rest are + * heads. + */ + for (i = 1; i < argc; i++) { + if (strcmp(argv[i], "--") == 0) + sep_seen = 1; + else if (strcmp(argv[i], "-h") == 0) + usage(builtin_merge_octopus_usage); + else if (sep_seen && !head_arg) + head_arg = argv[i]; + else { + struct object_id oid; + struct commit *commit; + + if (get_oid(argv[i], &oid)) + die("object %s not found.", argv[i]); + + commit = lookup_commit_or_die(&oid, argv[i]); + + if (sep_seen) + next_remote = commit_list_append(commit, next_remote); + else + next_base = commit_list_append(commit, next_base); + } + } + + /* + * Reject if this is not an octopus -- resolve should be used + * instead. + */ + if (commit_list_count(remotes) < 2) + return 2; + + return merge_strategies_octopus(the_repository, bases, head_arg, remotes); +} diff --git a/git-merge-octopus.sh b/git-merge-octopus.sh deleted file mode 100755 index 7d19d37951..0000000000 --- a/git-merge-octopus.sh +++ /dev/null @@ -1,112 +0,0 @@ -#!/bin/sh -# -# Copyright (c) 2005 Junio C Hamano -# -# Resolve two or more trees. -# - -. git-sh-setup - -LF=' -' - -# The first parameters up to -- are merge bases; the rest are heads. -bases= head= remotes= sep_seen= -for arg -do - case ",$sep_seen,$head,$arg," in - *,--,) - sep_seen=yes - ;; - ,yes,,*) - head=$arg - ;; - ,yes,*) - remotes="$remotes$arg " - ;; - *) - bases="$bases$arg " - ;; - esac -done - -# Reject if this is not an octopus -- resolve should be used instead. -case "$remotes" in -?*' '?*) - ;; -*) - exit 2 ;; -esac - -# MRC is the current "merge reference commit" -# MRT is the current "merge result tree" - -if ! git diff-index --quiet --cached HEAD -- -then - gettextln "Error: Your local changes to the following files would be overwritten by merge" - git diff-index --cached --name-only HEAD -- | sed -e 's/^/ /' - exit 2 -fi -MRC=$(git rev-parse --verify -q $head) -MRT=$(git write-tree) -NON_FF_MERGE=0 -OCTOPUS_FAILURE=0 -for SHA1 in $remotes -do - case "$OCTOPUS_FAILURE" in - 1) - # We allow only last one to have a hand-resolvable - # conflicts. Last round failed and we still had - # a head to merge. - gettextln "Automated merge did not work." - gettextln "Should not be doing an octopus." - exit 2 - esac - - eval pretty_name=\${GITHEAD_$SHA1:-$SHA1} - if test "$SHA1" = "$pretty_name" - then - SHA1_UP="$(echo "$SHA1" | tr a-z A-Z)" - eval pretty_name=\${GITHEAD_$SHA1_UP:-$pretty_name} - fi - common=$(git merge-base --all $SHA1 $MRC) || - die "$(eval_gettext "Unable to find common commit with \$pretty_name")" - - case "$LF$common$LF" in - *"$LF$SHA1$LF"*) - eval_gettextln "Already up to date with \$pretty_name" - continue - ;; - esac - - if test "$common,$NON_FF_MERGE" = "$MRC,0" - then - # The first head being merged was a fast-forward. - # Advance MRC to the head being merged, and use that - # tree as the intermediate result of the merge. - # We still need to count this as part of the parent set. - - eval_gettextln "Fast-forwarding to: \$pretty_name" - git read-tree -u -m $head $SHA1 || exit - MRC=$SHA1 MRT=$(git write-tree) - continue - fi - - NON_FF_MERGE=1 - - eval_gettextln "Trying simple merge with \$pretty_name" - git read-tree -u -m --aggressive $common $MRT $SHA1 || exit 2 - next=$(git write-tree 2>/dev/null) - if test $? -ne 0 - then - gettextln "Simple merge did not work, trying automatic merge." - git merge-index -o git-merge-one-file -a || - OCTOPUS_FAILURE=1 - next=$(git write-tree 2>/dev/null) - fi - - MRC="$MRC $SHA1" - MRT=$next -done - -exit "$OCTOPUS_FAILURE" diff --git a/git.c b/git.c index 64a1a1de41..d51fb5d2bf 100644 --- a/git.c +++ b/git.c @@ -539,6 +539,7 @@ static struct cmd_struct commands[] = { { "merge-base", cmd_merge_base, RUN_SETUP }, { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY }, { "merge-index", cmd_merge_index, RUN_SETUP | NO_PARSEOPT }, + { "merge-octopus", cmd_merge_octopus, RUN_SETUP | NO_PARSEOPT }, { "merge-ours", cmd_merge_ours, RUN_SETUP | NO_PARSEOPT }, { "merge-one-file", cmd_merge_one_file, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT }, { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT }, diff --git a/merge-strategies.c b/merge-strategies.c index 9aa07e91b5..4d9dd55296 100644 --- a/merge-strategies.c +++ b/merge-strategies.c @@ -1,5 +1,6 @@ #include "cache.h" #include "cache-tree.h" +#include "commit-reach.h" #include "dir.h" #include "lockfile.h" #include "merge-strategies.h" @@ -392,3 +393,179 @@ int merge_strategies_resolve(struct repository *r, return 0; } + +static int write_tree(struct repository *r, struct tree **reference_tree) +{ + struct object_id oid; + int ret; + + if (!(ret = write_index_as_tree(&oid, r->index, r->index_file, + WRITE_TREE_SILENT, NULL))) + *reference_tree = lookup_tree(r, &oid); + + return ret; +} + +static int octopus_fast_forward(struct repository *r, const char *branch_name, + struct tree *tree_head, struct tree *current_tree, + struct tree **reference_tree) +{ + /* + * The first head being merged was a fast-forward. Advance the + * reference commit to the head being merged, and use that tree + * as the intermediate result of the merge. We still need to + * count this as part of the parent set. + */ + struct tree_desc t[2]; + + printf(_("Fast-forwarding to: %s\n"), branch_name); + + init_tree_desc(t, tree_head->buffer, tree_head->size); + if (add_tree(current_tree, t + 1)) + return -1; + if (fast_forward(r, t, 2, 0)) + return -1; + if (write_tree(r, reference_tree)) + return -1; + + return 0; +} + +static int octopus_do_merge(struct repository *r, const char *branch_name, + struct commit_list *common, struct tree *current_tree, + struct tree **reference_tree) +{ + struct tree_desc t[MAX_UNPACK_TREES]; + struct commit_list *j; + int nr = 0, ret = 0; + + printf(_("Trying simple merge with %s\n"), branch_name); + + for (j = common; j; j = j->next) { + struct tree *tree = repo_get_commit_tree(r, j->item); + if (add_tree(tree, t + (nr++))) + return -1; + } + + if (add_tree(*reference_tree, t + (nr++))) + return -1; + if (add_tree(current_tree, t + (nr++))) + return -1; + if (fast_forward(r, t, nr, 1)) + return -1; + + if (write_tree(r, reference_tree)) { + struct lock_file lock = LOCK_INIT; + + puts(_("Simple merge did not work, trying automatic merge.")); + repo_hold_locked_index(r, &lock, LOCK_DIE_ON_ERROR); + ret = merge_all_index(r, 1, 0, merge_one_file_func, NULL); + write_locked_index(r->index, &lock, COMMIT_LOCK); + + write_tree(r, reference_tree); + } + + return ret ? -2 : 0; +} + +int merge_strategies_octopus(struct repository *r, + struct commit_list *bases, const char *head_arg, + struct commit_list *remotes) +{ + int ff_merge = 1, ret = 0, references = 1; + struct commit **reference_commit, *head_commit; + struct tree *reference_tree, *head_tree; + struct commit_list *i; + struct object_id head; + struct strbuf sb = STRBUF_INIT; + + get_oid(head_arg, &head); + head_commit = lookup_commit_reference(r, &head); + head_tree = repo_get_commit_tree(r, head_commit); + + if (parse_tree(head_tree)) + return 2; + + if (repo_index_has_changes(r, head_tree, &sb)) { + error(_("Your local changes to the following files " + "would be overwritten by merge:\n %s"), + sb.buf); + strbuf_release(&sb); + return 2; + } + + reference_commit = xcalloc(commit_list_count(remotes) + 1, + sizeof(struct commit *)); + reference_commit[0] = head_commit; + reference_tree = head_tree; + + for (i = remotes; i && i->item; i = i->next) { + struct commit *c = i->item; + struct object_id *oid = &c->object.oid; + struct tree *current_tree = repo_get_commit_tree(r, c); + struct commit_list *common, *j; + char *branch_name; + int k = 0, up_to_date = 0; + + if (ret) { + /* + * We allow only last one to have a + * hand-resolvable conflicts. Last round failed + * and we still had a head to merge. + */ + puts(_("Automated merge did not work.")); + puts(_("Should not be doing an octopus.")); + + free(reference_commit); + return 2; + } + + branch_name = merge_get_better_branch_name(oid_to_hex(oid)); + common = get_merge_bases_many(c, references, reference_commit); + + if (!common) { + error(_("Unable to find common commit with %s"), branch_name); + + free(branch_name); + free_commit_list(common); + free(reference_commit); + + return 2; + } + + for (j = common; j && !(up_to_date || !ff_merge); j = j->next) { + up_to_date |= oideq(&j->item->object.oid, oid); + + if (k < references) + ff_merge &= oideq(&j->item->object.oid, &reference_commit[k++]->object.oid); + } + + if (up_to_date) { + printf(_("Already up to date with %s\n"), branch_name); + + free(branch_name); + free_commit_list(common); + continue; + } + + if (ff_merge) { + ret = octopus_fast_forward(r, branch_name, head_tree, + current_tree, &reference_tree); + references = 0; + } else { + ret = octopus_do_merge(r, branch_name, common, + current_tree, &reference_tree); + } + + free(branch_name); + free_commit_list(common); + + if (ret == -1) + break; + + reference_commit[references++] = c; + } + + free(reference_commit); + return ret; +} diff --git a/merge-strategies.h b/merge-strategies.h index 47dcd71ad5..05c50159ec 100644 --- a/merge-strategies.h +++ b/merge-strategies.h @@ -39,5 +39,8 @@ int merge_all_index(struct repository *r, int oneshot, int quiet, int merge_strategies_resolve(struct repository *r, struct commit_list *bases, const char *head_arg, struct commit_list *remote); +int merge_strategies_octopus(struct repository *r, + struct commit_list *bases, const char *head_arg, + struct commit_list *remote); #endif /* MERGE_STRATEGIES_H */ -- 2.29.2.260.ge31aba42fb