Merge branch 'mv/merge-in-c'
authorJunio C Hamano <gitster@pobox.com>
Wed, 16 Jul 2008 02:09:46 +0000 (19:09 -0700)
committerJunio C Hamano <gitster@pobox.com>
Wed, 16 Jul 2008 02:09:46 +0000 (19:09 -0700)
* mv/merge-in-c:
reduce_heads(): protect from duplicate input
reduce_heads(): thinkofix
Add a new test for git-merge-resolve
t6021: add a new test for git-merge-resolve
Teach merge.log to "git-merge" again
Build in merge
Fix t7601-merge-pull-config.sh on AIX
git-commit-tree: make it usable from other builtins
Add new test case to ensure git-merge prepends the custom merge message
Add new test case to ensure git-merge reduces octopus parents when possible
Introduce reduce_heads()
Introduce get_merge_bases_many()
Add new test to ensure git-merge handles more than 25 refs.
Introduce get_octopus_merge_bases() in commit.c
git-fmt-merge-msg: make it usable from other builtins
Move read_cache_unmerged() to read-cache.c
Add new test to ensure git-merge handles pull.twohead and pull.octopus
Move parse-options's skip_prefix() to git-compat-util.h
Move commit_list_count() to commit.c
Move split_cmdline() to alias.c

Conflicts:
Makefile
parse-options.c

1  2 
Makefile
builtin-merge.c
cache.h
commit.h
git-compat-util.h
git.c
parse-options.c
diff --combined Makefile
index de151638bb5c20fe34a0ca5869652004cd90911d,fbc53e9cb35d262361111625104f169bf517ab24..9b52071b7304b5b3b2f88802210f7ed13274c0bd
+++ b/Makefile
@@@ -174,7 -174,7 +174,7 @@@ prefix = $(HOME
  bindir = $(prefix)/bin
  mandir = $(prefix)/share/man
  infodir = $(prefix)/share/info
 -gitexecdir = $(bindir)
 +gitexecdir = $(prefix)/libexec/git-core
  sharedir = $(prefix)/share
  template_dir = $(sharedir)/git-core/templates
  htmldir=$(sharedir)/doc/git-doc
@@@ -205,7 -205,7 +205,7 @@@ GITWEB_FAVICON = git-favicon.pn
  GITWEB_SITE_HEADER =
  GITWEB_SITE_FOOTER =
  
 -export prefix bindir gitexecdir sharedir template_dir htmldir sysconfdir
 +export prefix bindir gitexecdir sharedir htmldir sysconfdir
  
  CC = gcc
  AR = ar
@@@ -240,7 -240,7 +240,6 @@@ SCRIPT_SH += git-lost-found.s
  SCRIPT_SH += git-merge-octopus.sh
  SCRIPT_SH += git-merge-one-file.sh
  SCRIPT_SH += git-merge-resolve.sh
- SCRIPT_SH += git-merge.sh
 -SCRIPT_SH += git-merge-stupid.sh
  SCRIPT_SH += git-mergetool.sh
  SCRIPT_SH += git-parse-remote.sh
  SCRIPT_SH += git-pull.sh
@@@ -272,9 -272,11 +271,9 @@@ EXTRA_PROGRAMS 
  
  # ... and all the rest that could be moved out of bindir to gitexecdir
  PROGRAMS += $(EXTRA_PROGRAMS)
 -PROGRAMS += git-daemon$X
  PROGRAMS += git-fast-import$X
  PROGRAMS += git-fetch-pack$X
  PROGRAMS += git-hash-object$X
 -PROGRAMS += git-imap-send$X
  PROGRAMS += git-index-pack$X
  PROGRAMS += git-merge-index$X
  PROGRAMS += git-merge-tree$X
@@@ -334,7 -336,6 +333,7 @@@ LIB_H += builtin.
  LIB_H += cache.h
  LIB_H += cache-tree.h
  LIB_H += commit.h
 +LIB_H += compat/mingw.h
  LIB_H += csum-file.h
  LIB_H += decorate.h
  LIB_H += delta.h
@@@ -363,7 -364,6 +362,7 @@@ LIB_H += quote.
  LIB_H += reflog-walk.h
  LIB_H += refs.h
  LIB_H += remote.h
 +LIB_H += rerere.h
  LIB_H += revision.h
  LIB_H += run-command.h
  LIB_H += sha1-lookup.h
@@@ -448,7 -448,6 +447,7 @@@ LIB_OBJS += read-cache.
  LIB_OBJS += reflog-walk.o
  LIB_OBJS += refs.o
  LIB_OBJS += remote.o
 +LIB_OBJS += rerere.o
  LIB_OBJS += revision.o
  LIB_OBJS += run-command.o
  LIB_OBJS += server-info.o
@@@ -515,6 -514,7 +514,7 @@@ BUILTIN_OBJS += builtin-ls-remote.
  BUILTIN_OBJS += builtin-ls-tree.o
  BUILTIN_OBJS += builtin-mailinfo.o
  BUILTIN_OBJS += builtin-mailsplit.o
+ BUILTIN_OBJS += builtin-merge.o
  BUILTIN_OBJS += builtin-merge-base.o
  BUILTIN_OBJS += builtin-merge-file.o
  BUILTIN_OBJS += builtin-merge-ours.o
@@@ -717,36 -717,6 +717,36 @@@ ifeq ($(uname_S),HP-UX
        NO_HSTRERROR = YesPlease
        NO_SYS_SELECT_H = YesPlease
  endif
 +ifneq (,$(findstring MINGW,$(uname_S)))
 +      NO_MMAP = YesPlease
 +      NO_PREAD = YesPlease
 +      NO_OPENSSL = YesPlease
 +      NO_CURL = YesPlease
 +      NO_SYMLINK_HEAD = YesPlease
 +      NO_IPV6 = YesPlease
 +      NO_SETENV = YesPlease
 +      NO_UNSETENV = YesPlease
 +      NO_STRCASESTR = YesPlease
 +      NO_STRLCPY = YesPlease
 +      NO_MEMMEM = YesPlease
 +      NEEDS_LIBICONV = YesPlease
 +      OLD_ICONV = YesPlease
 +      NO_C99_FORMAT = YesPlease
 +      NO_STRTOUMAX = YesPlease
 +      NO_MKDTEMP = YesPlease
 +      SNPRINTF_RETURNS_BOGUS = YesPlease
 +      NO_SVN_TESTS = YesPlease
 +      NO_PERL_MAKEMAKER = YesPlease
 +      NO_POSIX_ONLY_PROGRAMS = YesPlease
 +      COMPAT_CFLAGS += -D__USE_MINGW_ACCESS -DNOGDI -Icompat
 +      COMPAT_CFLAGS += -DSNPRINTF_SIZE_CORR=1
 +      COMPAT_CFLAGS += -DSTRIP_EXTENSION=\".exe\"
 +      COMPAT_OBJS += compat/mingw.o compat/fnmatch.o compat/regex.o
 +      EXTLIBS += -lws2_32
 +      X = .exe
 +      template_dir = ../share/git-core/templates/
 +      ETC_GITCONFIG = ../etc/gitconfig
 +endif
  ifneq (,$(findstring arm,$(uname_M)))
        ARM_SHA1 = YesPlease
  endif
@@@ -807,10 -777,6 +807,10 @@@ ifdef ZLIB_PAT
  endif
  EXTLIBS += -lz
  
 +ifndef NO_POSIX_ONLY_PROGRAMS
 +      PROGRAMS += git-daemon$X
 +      PROGRAMS += git-imap-send$X
 +endif
  ifndef NO_OPENSSL
        OPENSSL_LIBSSL = -lssl
        ifdef OPENSSLDIR
@@@ -1267,7 -1233,7 +1267,7 @@@ endi
  
  ### Testing rules
  
 -TEST_PROGRAMS = test-chmtime$X test-genrandom$X test-date$X test-delta$X test-sha1$X test-match-trees$X test-absolute-path$X test-parse-options$X
 +TEST_PROGRAMS = test-chmtime$X test-genrandom$X test-date$X test-delta$X test-sha1$X test-match-trees$X test-parse-options$X test-path-utils$X
  
  all:: $(TEST_PROGRAMS)
  
@@@ -1302,18 -1268,11 +1302,18 @@@ remove-dashes
  
  ### Installation rules
  
 +ifeq ($(firstword $(subst /, ,$(template_dir))),..)
 +template_instdir = $(gitexecdir)/$(template_dir)
 +else
 +template_instdir = $(template_dir)
 +endif
 +export template_instdir
 +
  install: all
        $(INSTALL) -d -m 755 '$(DESTDIR_SQ)$(bindir_SQ)'
        $(INSTALL) -d -m 755 '$(DESTDIR_SQ)$(gitexecdir_SQ)'
        $(INSTALL) $(ALL_PROGRAMS) '$(DESTDIR_SQ)$(gitexecdir_SQ)'
 -      $(INSTALL) git$X '$(DESTDIR_SQ)$(bindir_SQ)'
 +      $(INSTALL) git$X git-upload-pack$X git-receive-pack$X git-upload-archive$X '$(DESTDIR_SQ)$(bindir_SQ)'
        $(MAKE) -C templates DESTDIR='$(DESTDIR_SQ)' install
        $(MAKE) -C perl prefix='$(prefix_SQ)' DESTDIR='$(DESTDIR_SQ)' install
  ifndef NO_TCLTK
@@@ -1331,7 -1290,6 +1331,7 @@@ endi
  ifneq (,$X)
        $(foreach p,$(patsubst %$X,%,$(filter %$X,$(ALL_PROGRAMS) $(BUILT_INS) git$X)), $(RM) '$(DESTDIR_SQ)$(gitexecdir_SQ)/$p';)
  endif
 +      ./check_bindir 'z$(bindir_SQ)' 'z$(gitexecdir_SQ)' '$(DESTDIR_SQ)$(bindir_SQ)/git-shell$X'
  
  install-doc:
        $(MAKE) -C Documentation install
@@@ -1430,7 -1388,7 +1430,7 @@@ check-docs:
        do \
                case "$$v" in \
                git-merge-octopus | git-merge-ours | git-merge-recursive | \
 -              git-merge-resolve | git-merge-stupid | git-merge-subtree | \
 +              git-merge-resolve | git-merge-subtree | \
                git-fsck-objects | git-init-db | \
                git-?*--?* ) continue ;; \
                esac ; \
diff --combined builtin-merge.c
index 0000000000000000000000000000000000000000,2ee16746908179960fcd57dc16d042d24f741833..129b4e62dd3bc3662f8f076e39c90b109f4bd669
mode 000000,100644..100644
--- /dev/null
@@@ -1,0 -1,1155 +1,1156 @@@
+ /*
+  * Builtin "git merge"
+  *
+  * Copyright (c) 2008 Miklos Vajna <vmiklos@frugalware.org>
+  *
+  * Based on git-merge.sh by Junio C Hamano.
+  */
+ #include "cache.h"
+ #include "parse-options.h"
+ #include "builtin.h"
+ #include "run-command.h"
+ #include "diff.h"
+ #include "refs.h"
+ #include "commit.h"
+ #include "diffcore.h"
+ #include "revision.h"
+ #include "unpack-trees.h"
+ #include "cache-tree.h"
+ #include "dir.h"
+ #include "utf8.h"
+ #include "log-tree.h"
+ #include "color.h"
++#include "rerere.h"
+ #define DEFAULT_TWOHEAD (1<<0)
+ #define DEFAULT_OCTOPUS (1<<1)
+ #define NO_FAST_FORWARD (1<<2)
+ #define NO_TRIVIAL      (1<<3)
+ struct strategy {
+       const char *name;
+       unsigned attr;
+ };
+ static const char * const builtin_merge_usage[] = {
+       "git-merge [options] <remote>...",
+       "git-merge [options] <msg> HEAD <remote>",
+       NULL
+ };
+ static int show_diffstat = 1, option_log, squash;
+ static int option_commit = 1, allow_fast_forward = 1;
+ static int allow_trivial = 1, have_message;
+ static struct strbuf merge_msg;
+ static struct commit_list *remoteheads;
+ static unsigned char head[20], stash[20];
+ static struct strategy **use_strategies;
+ static size_t use_strategies_nr, use_strategies_alloc;
+ static const char *branch;
+ static struct strategy all_strategy[] = {
+       { "recur",      NO_TRIVIAL },
+       { "recursive",  DEFAULT_TWOHEAD | NO_TRIVIAL },
+       { "octopus",    DEFAULT_OCTOPUS },
+       { "resolve",    0 },
+       { "stupid",     0 },
+       { "ours",       NO_FAST_FORWARD | NO_TRIVIAL },
+       { "subtree",    NO_FAST_FORWARD | NO_TRIVIAL },
+ };
+ static const char *pull_twohead, *pull_octopus;
+ static int option_parse_message(const struct option *opt,
+                               const char *arg, int unset)
+ {
+       struct strbuf *buf = opt->value;
+       if (unset)
+               strbuf_setlen(buf, 0);
+       else {
+               strbuf_addf(buf, "%s\n\n", arg);
+               have_message = 1;
+       }
+       return 0;
+ }
+ static struct strategy *get_strategy(const char *name)
+ {
+       int i;
+       if (!name)
+               return NULL;
+       for (i = 0; i < ARRAY_SIZE(all_strategy); i++)
+               if (!strcmp(name, all_strategy[i].name))
+                       return &all_strategy[i];
+       return NULL;
+ }
+ static void append_strategy(struct strategy *s)
+ {
+       ALLOC_GROW(use_strategies, use_strategies_nr + 1, use_strategies_alloc);
+       use_strategies[use_strategies_nr++] = s;
+ }
+ static int option_parse_strategy(const struct option *opt,
+                                const char *name, int unset)
+ {
+       int i;
+       struct strategy *s;
+       if (unset)
+               return 0;
+       s = get_strategy(name);
+       if (s)
+               append_strategy(s);
+       else {
+               struct strbuf err;
+               strbuf_init(&err, 0);
+               for (i = 0; i < ARRAY_SIZE(all_strategy); i++)
+                       strbuf_addf(&err, " %s", all_strategy[i].name);
+               fprintf(stderr, "Could not find merge strategy '%s'.\n", name);
+               fprintf(stderr, "Available strategies are:%s.\n", err.buf);
+               exit(1);
+       }
+       return 0;
+ }
+ static int option_parse_n(const struct option *opt,
+                         const char *arg, int unset)
+ {
+       show_diffstat = unset;
+       return 0;
+ }
+ static struct option builtin_merge_options[] = {
+       { OPTION_CALLBACK, 'n', NULL, NULL, NULL,
+               "do not show a diffstat at the end of the merge",
+               PARSE_OPT_NOARG, option_parse_n },
+       OPT_BOOLEAN(0, "stat", &show_diffstat,
+               "show a diffstat at the end of the merge"),
+       OPT_BOOLEAN(0, "summary", &show_diffstat, "(synonym to --stat)"),
+       OPT_BOOLEAN(0, "log", &option_log,
+               "add list of one-line log to merge commit message"),
+       OPT_BOOLEAN(0, "squash", &squash,
+               "create a single commit instead of doing a merge"),
+       OPT_BOOLEAN(0, "commit", &option_commit,
+               "perform a commit if the merge succeeds (default)"),
+       OPT_BOOLEAN(0, "ff", &allow_fast_forward,
+               "allow fast forward (default)"),
+       OPT_CALLBACK('s', "strategy", &use_strategies, "strategy",
+               "merge strategy to use", option_parse_strategy),
+       OPT_CALLBACK('m', "message", &merge_msg, "message",
+               "message to be used for the merge commit (if any)",
+               option_parse_message),
+       OPT_END()
+ };
+ /* Cleans up metadata that is uninteresting after a succeeded merge. */
+ static void drop_save(void)
+ {
+       unlink(git_path("MERGE_HEAD"));
+       unlink(git_path("MERGE_MSG"));
+ }
+ static void save_state(void)
+ {
+       int len;
+       struct child_process cp;
+       struct strbuf buffer = STRBUF_INIT;
+       const char *argv[] = {"stash", "create", NULL};
+       memset(&cp, 0, sizeof(cp));
+       cp.argv = argv;
+       cp.out = -1;
+       cp.git_cmd = 1;
+       if (start_command(&cp))
+               die("could not run stash.");
+       len = strbuf_read(&buffer, cp.out, 1024);
+       close(cp.out);
+       if (finish_command(&cp) || len < 0)
+               die("stash failed");
+       else if (!len)
+               return;
+       strbuf_setlen(&buffer, buffer.len-1);
+       if (get_sha1(buffer.buf, stash))
+               die("not a valid object: %s", buffer.buf);
+ }
+ static void reset_hard(unsigned const char *sha1, int verbose)
+ {
+       int i = 0;
+       const char *args[6];
+       args[i++] = "read-tree";
+       if (verbose)
+               args[i++] = "-v";
+       args[i++] = "--reset";
+       args[i++] = "-u";
+       args[i++] = sha1_to_hex(sha1);
+       args[i] = NULL;
+       if (run_command_v_opt(args, RUN_GIT_CMD))
+               die("read-tree failed");
+ }
+ static void restore_state(void)
+ {
+       struct strbuf sb;
+       const char *args[] = { "stash", "apply", NULL, NULL };
+       if (is_null_sha1(stash))
+               return;
+       reset_hard(head, 1);
+       strbuf_init(&sb, 0);
+       args[2] = sha1_to_hex(stash);
+       /*
+        * It is OK to ignore error here, for example when there was
+        * nothing to restore.
+        */
+       run_command_v_opt(args, RUN_GIT_CMD);
+       strbuf_release(&sb);
+       refresh_cache(REFRESH_QUIET);
+ }
+ /* This is called when no merge was necessary. */
+ static void finish_up_to_date(const char *msg)
+ {
+       printf("%s%s\n", squash ? " (nothing to squash)" : "", msg);
+       drop_save();
+ }
+ static void squash_message(void)
+ {
+       struct rev_info rev;
+       struct commit *commit;
+       struct strbuf out;
+       struct commit_list *j;
+       int fd;
+       printf("Squash commit -- not updating HEAD\n");
+       fd = open(git_path("SQUASH_MSG"), O_WRONLY | O_CREAT, 0666);
+       if (fd < 0)
+               die("Could not write to %s", git_path("SQUASH_MSG"));
+       init_revisions(&rev, NULL);
+       rev.ignore_merges = 1;
+       rev.commit_format = CMIT_FMT_MEDIUM;
+       commit = lookup_commit(head);
+       commit->object.flags |= UNINTERESTING;
+       add_pending_object(&rev, &commit->object, NULL);
+       for (j = remoteheads; j; j = j->next)
+               add_pending_object(&rev, &j->item->object, NULL);
+       setup_revisions(0, NULL, &rev, NULL);
+       if (prepare_revision_walk(&rev))
+               die("revision walk setup failed");
+       strbuf_init(&out, 0);
+       strbuf_addstr(&out, "Squashed commit of the following:\n");
+       while ((commit = get_revision(&rev)) != NULL) {
+               strbuf_addch(&out, '\n');
+               strbuf_addf(&out, "commit %s\n",
+                       sha1_to_hex(commit->object.sha1));
+               pretty_print_commit(rev.commit_format, commit, &out, rev.abbrev,
+                       NULL, NULL, rev.date_mode, 0);
+       }
+       write(fd, out.buf, out.len);
+       close(fd);
+       strbuf_release(&out);
+ }
+ static int run_hook(const char *name)
+ {
+       struct child_process hook;
+       const char *argv[3], *env[2];
+       char index[PATH_MAX];
+       argv[0] = git_path("hooks/%s", name);
+       if (access(argv[0], X_OK) < 0)
+               return 0;
+       snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", get_index_file());
+       env[0] = index;
+       env[1] = NULL;
+       if (squash)
+               argv[1] = "1";
+       else
+               argv[1] = "0";
+       argv[2] = NULL;
+       memset(&hook, 0, sizeof(hook));
+       hook.argv = argv;
+       hook.no_stdin = 1;
+       hook.stdout_to_stderr = 1;
+       hook.env = env;
+       return run_command(&hook);
+ }
+ static void finish(const unsigned char *new_head, const char *msg)
+ {
+       struct strbuf reflog_message;
+       strbuf_init(&reflog_message, 0);
+       if (!msg)
+               strbuf_addstr(&reflog_message, getenv("GIT_REFLOG_ACTION"));
+       else {
+               printf("%s\n", msg);
+               strbuf_addf(&reflog_message, "%s: %s",
+                       getenv("GIT_REFLOG_ACTION"), msg);
+       }
+       if (squash) {
+               squash_message();
+       } else {
+               if (!merge_msg.len)
+                       printf("No merge message -- not updating HEAD\n");
+               else {
+                       const char *argv_gc_auto[] = { "gc", "--auto", NULL };
+                       update_ref(reflog_message.buf, "HEAD",
+                               new_head, head, 0,
+                               DIE_ON_ERR);
+                       /*
+                        * We ignore errors in 'gc --auto', since the
+                        * user should see them.
+                        */
+                       run_command_v_opt(argv_gc_auto, RUN_GIT_CMD);
+               }
+       }
+       if (new_head && show_diffstat) {
+               struct diff_options opts;
+               diff_setup(&opts);
+               opts.output_format |=
+                       DIFF_FORMAT_SUMMARY | DIFF_FORMAT_DIFFSTAT;
+               opts.detect_rename = DIFF_DETECT_RENAME;
+               if (diff_use_color_default > 0)
+                       DIFF_OPT_SET(&opts, COLOR_DIFF);
+               if (diff_setup_done(&opts) < 0)
+                       die("diff_setup_done failed");
+               diff_tree_sha1(head, new_head, "", &opts);
+               diffcore_std(&opts);
+               diff_flush(&opts);
+       }
+       /* Run a post-merge hook */
+       run_hook("post-merge");
+       strbuf_release(&reflog_message);
+ }
+ /* Get the name for the merge commit's message. */
+ static void merge_name(const char *remote, struct strbuf *msg)
+ {
+       struct object *remote_head;
+       unsigned char branch_head[20], buf_sha[20];
+       struct strbuf buf;
+       const char *ptr;
+       int len, early;
+       memset(branch_head, 0, sizeof(branch_head));
+       remote_head = peel_to_type(remote, 0, NULL, OBJ_COMMIT);
+       if (!remote_head)
+               die("'%s' does not point to a commit", remote);
+       strbuf_init(&buf, 0);
+       strbuf_addstr(&buf, "refs/heads/");
+       strbuf_addstr(&buf, remote);
+       resolve_ref(buf.buf, branch_head, 0, 0);
+       if (!hashcmp(remote_head->sha1, branch_head)) {
+               strbuf_addf(msg, "%s\t\tbranch '%s' of .\n",
+                       sha1_to_hex(branch_head), remote);
+               return;
+       }
+       /* See if remote matches <name>^^^.. or <name>~<number> */
+       for (len = 0, ptr = remote + strlen(remote);
+            remote < ptr && ptr[-1] == '^';
+            ptr--)
+               len++;
+       if (len)
+               early = 1;
+       else {
+               early = 0;
+               ptr = strrchr(remote, '~');
+               if (ptr) {
+                       int seen_nonzero = 0;
+                       len++; /* count ~ */
+                       while (*++ptr && isdigit(*ptr)) {
+                               seen_nonzero |= (*ptr != '0');
+                               len++;
+                       }
+                       if (*ptr)
+                               len = 0; /* not ...~<number> */
+                       else if (seen_nonzero)
+                               early = 1;
+                       else if (len == 1)
+                               early = 1; /* "name~" is "name~1"! */
+               }
+       }
+       if (len) {
+               struct strbuf truname = STRBUF_INIT;
+               strbuf_addstr(&truname, "refs/heads/");
+               strbuf_addstr(&truname, remote);
+               strbuf_setlen(&truname, len+11);
+               if (resolve_ref(truname.buf, buf_sha, 0, 0)) {
+                       strbuf_addf(msg,
+                                   "%s\t\tbranch '%s'%s of .\n",
+                                   sha1_to_hex(remote_head->sha1),
+                                   truname.buf,
+                                   (early ? " (early part)" : ""));
+                       return;
+               }
+       }
+       if (!strcmp(remote, "FETCH_HEAD") &&
+                       !access(git_path("FETCH_HEAD"), R_OK)) {
+               FILE *fp;
+               struct strbuf line;
+               char *ptr;
+               strbuf_init(&line, 0);
+               fp = fopen(git_path("FETCH_HEAD"), "r");
+               if (!fp)
+                       die("could not open %s for reading: %s",
+                               git_path("FETCH_HEAD"), strerror(errno));
+               strbuf_getline(&line, fp, '\n');
+               fclose(fp);
+               ptr = strstr(line.buf, "\tnot-for-merge\t");
+               if (ptr)
+                       strbuf_remove(&line, ptr-line.buf+1, 13);
+               strbuf_addbuf(msg, &line);
+               strbuf_release(&line);
+               return;
+       }
+       strbuf_addf(msg, "%s\t\tcommit '%s'\n",
+               sha1_to_hex(remote_head->sha1), remote);
+ }
+ int git_merge_config(const char *k, const char *v, void *cb)
+ {
+       if (branch && !prefixcmp(k, "branch.") &&
+               !prefixcmp(k + 7, branch) &&
+               !strcmp(k + 7 + strlen(branch), ".mergeoptions")) {
+               const char **argv;
+               int argc;
+               char *buf;
+               buf = xstrdup(v);
+               argc = split_cmdline(buf, &argv);
+               argv = xrealloc(argv, sizeof(*argv) * (argc + 2));
+               memmove(argv + 1, argv, sizeof(*argv) * (argc + 1));
+               argc++;
+               parse_options(argc, argv, builtin_merge_options,
+                             builtin_merge_usage, 0);
+               free(buf);
+       }
+       if (!strcmp(k, "merge.diffstat") || !strcmp(k, "merge.stat"))
+               show_diffstat = git_config_bool(k, v);
+       else if (!strcmp(k, "pull.twohead"))
+               return git_config_string(&pull_twohead, k, v);
+       else if (!strcmp(k, "pull.octopus"))
+               return git_config_string(&pull_octopus, k, v);
+       else if (!strcmp(k, "merge.log") || !strcmp(k, "merge.summary"))
+               option_log = git_config_bool(k, v);
+       return git_diff_ui_config(k, v, cb);
+ }
+ static int read_tree_trivial(unsigned char *common, unsigned char *head,
+                            unsigned char *one)
+ {
+       int i, nr_trees = 0;
+       struct tree *trees[MAX_UNPACK_TREES];
+       struct tree_desc t[MAX_UNPACK_TREES];
+       struct unpack_trees_options opts;
+       memset(&opts, 0, sizeof(opts));
+       opts.head_idx = 2;
+       opts.src_index = &the_index;
+       opts.dst_index = &the_index;
+       opts.update = 1;
+       opts.verbose_update = 1;
+       opts.trivial_merges_only = 1;
+       opts.merge = 1;
+       trees[nr_trees] = parse_tree_indirect(common);
+       if (!trees[nr_trees++])
+               return -1;
+       trees[nr_trees] = parse_tree_indirect(head);
+       if (!trees[nr_trees++])
+               return -1;
+       trees[nr_trees] = parse_tree_indirect(one);
+       if (!trees[nr_trees++])
+               return -1;
+       opts.fn = threeway_merge;
+       cache_tree_free(&active_cache_tree);
+       for (i = 0; i < nr_trees; i++) {
+               parse_tree(trees[i]);
+               init_tree_desc(t+i, trees[i]->buffer, trees[i]->size);
+       }
+       if (unpack_trees(nr_trees, t, &opts))
+               return -1;
+       return 0;
+ }
+ static void write_tree_trivial(unsigned char *sha1)
+ {
+       if (write_cache_as_tree(sha1, 0, NULL))
+               die("git write-tree failed to write a tree");
+ }
+ static int try_merge_strategy(const char *strategy, struct commit_list *common,
+                             const char *head_arg)
+ {
+       const char **args;
+       int i = 0, ret;
+       struct commit_list *j;
+       struct strbuf buf;
+       args = xmalloc((4 + commit_list_count(common) +
+                       commit_list_count(remoteheads)) * sizeof(char *));
+       strbuf_init(&buf, 0);
+       strbuf_addf(&buf, "merge-%s", strategy);
+       args[i++] = buf.buf;
+       for (j = common; j; j = j->next)
+               args[i++] = xstrdup(sha1_to_hex(j->item->object.sha1));
+       args[i++] = "--";
+       args[i++] = head_arg;
+       for (j = remoteheads; j; j = j->next)
+               args[i++] = xstrdup(sha1_to_hex(j->item->object.sha1));
+       args[i] = NULL;
+       ret = run_command_v_opt(args, RUN_GIT_CMD);
+       strbuf_release(&buf);
+       i = 1;
+       for (j = common; j; j = j->next)
+               free((void *)args[i++]);
+       i += 2;
+       for (j = remoteheads; j; j = j->next)
+               free((void *)args[i++]);
+       free(args);
+       return -ret;
+ }
+ static void count_diff_files(struct diff_queue_struct *q,
+                            struct diff_options *opt, void *data)
+ {
+       int *count = data;
+       (*count) += q->nr;
+ }
+ static int count_unmerged_entries(void)
+ {
+       const struct index_state *state = &the_index;
+       int i, ret = 0;
+       for (i = 0; i < state->cache_nr; i++)
+               if (ce_stage(state->cache[i]))
+                       ret++;
+       return ret;
+ }
+ static int checkout_fast_forward(unsigned char *head, unsigned char *remote)
+ {
+       struct tree *trees[MAX_UNPACK_TREES];
+       struct unpack_trees_options opts;
+       struct tree_desc t[MAX_UNPACK_TREES];
+       int i, fd, nr_trees = 0;
+       struct dir_struct dir;
+       struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
+       if (read_cache_unmerged())
+               die("you need to resolve your current index first");
+       fd = hold_locked_index(lock_file, 1);
+       memset(&trees, 0, sizeof(trees));
+       memset(&opts, 0, sizeof(opts));
+       memset(&t, 0, sizeof(t));
+       dir.show_ignored = 1;
+       dir.exclude_per_dir = ".gitignore";
+       opts.dir = &dir;
+       opts.head_idx = 1;
+       opts.src_index = &the_index;
+       opts.dst_index = &the_index;
+       opts.update = 1;
+       opts.verbose_update = 1;
+       opts.merge = 1;
+       opts.fn = twoway_merge;
+       trees[nr_trees] = parse_tree_indirect(head);
+       if (!trees[nr_trees++])
+               return -1;
+       trees[nr_trees] = parse_tree_indirect(remote);
+       if (!trees[nr_trees++])
+               return -1;
+       for (i = 0; i < nr_trees; i++) {
+               parse_tree(trees[i]);
+               init_tree_desc(t+i, trees[i]->buffer, trees[i]->size);
+       }
+       if (unpack_trees(nr_trees, t, &opts))
+               return -1;
+       if (write_cache(fd, active_cache, active_nr) ||
+               commit_locked_index(lock_file))
+               die("unable to write new index file");
+       return 0;
+ }
+ static void split_merge_strategies(const char *string, struct strategy **list,
+                                  int *nr, int *alloc)
+ {
+       char *p, *q, *buf;
+       if (!string)
+               return;
+       buf = xstrdup(string);
+       q = buf;
+       for (;;) {
+               p = strchr(q, ' ');
+               if (!p) {
+                       ALLOC_GROW(*list, *nr + 1, *alloc);
+                       (*list)[(*nr)++].name = xstrdup(q);
+                       free(buf);
+                       return;
+               } else {
+                       *p = '\0';
+                       ALLOC_GROW(*list, *nr + 1, *alloc);
+                       (*list)[(*nr)++].name = xstrdup(q);
+                       q = ++p;
+               }
+       }
+ }
+ static void add_strategies(const char *string, unsigned attr)
+ {
+       struct strategy *list = NULL;
+       int list_alloc = 0, list_nr = 0, i;
+       memset(&list, 0, sizeof(list));
+       split_merge_strategies(string, &list, &list_nr, &list_alloc);
+       if (list != NULL) {
+               for (i = 0; i < list_nr; i++) {
+                       struct strategy *s;
+                       s = get_strategy(list[i].name);
+                       if (s)
+                               append_strategy(s);
+               }
+               return;
+       }
+       for (i = 0; i < ARRAY_SIZE(all_strategy); i++)
+               if (all_strategy[i].attr & attr)
+                       append_strategy(&all_strategy[i]);
+ }
+ static int merge_trivial(void)
+ {
+       unsigned char result_tree[20], result_commit[20];
+       struct commit_list parent;
+       write_tree_trivial(result_tree);
+       printf("Wonderful.\n");
+       parent.item = remoteheads->item;
+       parent.next = NULL;
+       commit_tree(merge_msg.buf, result_tree, &parent, result_commit);
+       finish(result_commit, "In-index merge");
+       drop_save();
+       return 0;
+ }
+ static int finish_automerge(struct commit_list *common,
+                           unsigned char *result_tree,
+                           const char *wt_strategy)
+ {
+       struct commit_list *parents = NULL, *j;
+       struct strbuf buf = STRBUF_INIT;
+       unsigned char result_commit[20];
+       free_commit_list(common);
+       if (allow_fast_forward) {
+               parents = remoteheads;
+               commit_list_insert(lookup_commit(head), &parents);
+               parents = reduce_heads(parents);
+       } else {
+               struct commit_list **pptr = &parents;
+               pptr = &commit_list_insert(lookup_commit(head),
+                               pptr)->next;
+               for (j = remoteheads; j; j = j->next)
+                       pptr = &commit_list_insert(j->item, pptr)->next;
+       }
+       free_commit_list(remoteheads);
+       strbuf_addch(&merge_msg, '\n');
+       commit_tree(merge_msg.buf, result_tree, parents, result_commit);
+       strbuf_addf(&buf, "Merge made by %s.", wt_strategy);
+       finish(result_commit, buf.buf);
+       strbuf_release(&buf);
+       drop_save();
+       return 0;
+ }
+ static int suggest_conflicts(void)
+ {
+       FILE *fp;
+       int pos;
+       fp = fopen(git_path("MERGE_MSG"), "a");
+       if (!fp)
+               die("Could open %s for writing", git_path("MERGE_MSG"));
+       fprintf(fp, "\nConflicts:\n");
+       for (pos = 0; pos < active_nr; pos++) {
+               struct cache_entry *ce = active_cache[pos];
+               if (ce_stage(ce)) {
+                       fprintf(fp, "\t%s\n", ce->name);
+                       while (pos + 1 < active_nr &&
+                                       !strcmp(ce->name,
+                                               active_cache[pos + 1]->name))
+                               pos++;
+               }
+       }
+       fclose(fp);
+       rerere();
+       printf("Automatic merge failed; "
+                       "fix conflicts and then commit the result.\n");
+       return 1;
+ }
+ static struct commit *is_old_style_invocation(int argc, const char **argv)
+ {
+       struct commit *second_token = NULL;
+       if (argc > 1) {
+               unsigned char second_sha1[20];
+               if (get_sha1(argv[1], second_sha1))
+                       return NULL;
+               second_token = lookup_commit_reference_gently(second_sha1, 0);
+               if (!second_token)
+                       die("'%s' is not a commit", argv[1]);
+               if (hashcmp(second_token->object.sha1, head))
+                       return NULL;
+       }
+       return second_token;
+ }
+ static int evaluate_result(void)
+ {
+       int cnt = 0;
+       struct rev_info rev;
+       if (read_cache() < 0)
+               die("failed to read the cache");
+       /* Check how many files differ. */
+       init_revisions(&rev, "");
+       setup_revisions(0, NULL, &rev, NULL);
+       rev.diffopt.output_format |=
+               DIFF_FORMAT_CALLBACK;
+       rev.diffopt.format_callback = count_diff_files;
+       rev.diffopt.format_callback_data = &cnt;
+       run_diff_files(&rev, 0);
+       /*
+        * Check how many unmerged entries are
+        * there.
+        */
+       cnt += count_unmerged_entries();
+       return cnt;
+ }
+ int cmd_merge(int argc, const char **argv, const char *prefix)
+ {
+       unsigned char result_tree[20];
+       struct strbuf buf;
+       const char *head_arg;
+       int flag, head_invalid = 0, i;
+       int best_cnt = -1, merge_was_ok = 0, automerge_was_ok = 0;
+       struct commit_list *common = NULL;
+       const char *best_strategy = NULL, *wt_strategy = NULL;
+       struct commit_list **remotes = &remoteheads;
+       setup_work_tree();
+       if (unmerged_cache())
+               die("You are in the middle of a conflicted merge.");
+       /*
+        * Check if we are _not_ on a detached HEAD, i.e. if there is a
+        * current branch.
+        */
+       branch = resolve_ref("HEAD", head, 0, &flag);
+       if (branch && !prefixcmp(branch, "refs/heads/"))
+               branch += 11;
+       if (is_null_sha1(head))
+               head_invalid = 1;
+       git_config(git_merge_config, NULL);
+       /* for color.ui */
+       if (diff_use_color_default == -1)
+               diff_use_color_default = git_use_color_default;
+       argc = parse_options(argc, argv, builtin_merge_options,
+                       builtin_merge_usage, 0);
+       if (squash) {
+               if (!allow_fast_forward)
+                       die("You cannot combine --squash with --no-ff.");
+               option_commit = 0;
+       }
+       if (!argc)
+               usage_with_options(builtin_merge_usage,
+                       builtin_merge_options);
+       /*
+        * This could be traditional "merge <msg> HEAD <commit>..."  and
+        * the way we can tell it is to see if the second token is HEAD,
+        * but some people might have misused the interface and used a
+        * committish that is the same as HEAD there instead.
+        * Traditional format never would have "-m" so it is an
+        * additional safety measure to check for it.
+        */
+       strbuf_init(&buf, 0);
+       if (!have_message && is_old_style_invocation(argc, argv)) {
+               strbuf_addstr(&merge_msg, argv[0]);
+               head_arg = argv[1];
+               argv += 2;
+               argc -= 2;
+       } else if (head_invalid) {
+               struct object *remote_head;
+               /*
+                * If the merged head is a valid one there is no reason
+                * to forbid "git merge" into a branch yet to be born.
+                * We do the same for "git pull".
+                */
+               if (argc != 1)
+                       die("Can merge only exactly one commit into "
+                               "empty head");
+               remote_head = peel_to_type(argv[0], 0, NULL, OBJ_COMMIT);
+               if (!remote_head)
+                       die("%s - not something we can merge", argv[0]);
+               update_ref("initial pull", "HEAD", remote_head->sha1, NULL, 0,
+                               DIE_ON_ERR);
+               reset_hard(remote_head->sha1, 0);
+               return 0;
+       } else {
+               struct strbuf msg;
+               /* We are invoked directly as the first-class UI. */
+               head_arg = "HEAD";
+               /*
+                * All the rest are the commits being merged;
+                * prepare the standard merge summary message to
+                * be appended to the given message.  If remote
+                * is invalid we will die later in the common
+                * codepath so we discard the error in this
+                * loop.
+                */
+               strbuf_init(&msg, 0);
+               for (i = 0; i < argc; i++)
+                       merge_name(argv[i], &msg);
+               fmt_merge_msg(option_log, &msg, &merge_msg);
+               if (merge_msg.len)
+                       strbuf_setlen(&merge_msg, merge_msg.len-1);
+       }
+       if (head_invalid || !argc)
+               usage_with_options(builtin_merge_usage,
+                       builtin_merge_options);
+       strbuf_addstr(&buf, "merge");
+       for (i = 0; i < argc; i++)
+               strbuf_addf(&buf, " %s", argv[i]);
+       setenv("GIT_REFLOG_ACTION", buf.buf, 0);
+       strbuf_reset(&buf);
+       for (i = 0; i < argc; i++) {
+               struct object *o;
+               o = peel_to_type(argv[i], 0, NULL, OBJ_COMMIT);
+               if (!o)
+                       die("%s - not something we can merge", argv[i]);
+               remotes = &commit_list_insert(lookup_commit(o->sha1),
+                       remotes)->next;
+               strbuf_addf(&buf, "GITHEAD_%s", sha1_to_hex(o->sha1));
+               setenv(buf.buf, argv[i], 1);
+               strbuf_reset(&buf);
+       }
+       if (!use_strategies) {
+               if (!remoteheads->next)
+                       add_strategies(pull_twohead, DEFAULT_TWOHEAD);
+               else
+                       add_strategies(pull_octopus, DEFAULT_OCTOPUS);
+       }
+       for (i = 0; i < use_strategies_nr; i++) {
+               if (use_strategies[i]->attr & NO_FAST_FORWARD)
+                       allow_fast_forward = 0;
+               if (use_strategies[i]->attr & NO_TRIVIAL)
+                       allow_trivial = 0;
+       }
+       if (!remoteheads->next)
+               common = get_merge_bases(lookup_commit(head),
+                               remoteheads->item, 1);
+       else {
+               struct commit_list *list = remoteheads;
+               commit_list_insert(lookup_commit(head), &list);
+               common = get_octopus_merge_bases(list);
+               free(list);
+       }
+       update_ref("updating ORIG_HEAD", "ORIG_HEAD", head, NULL, 0,
+               DIE_ON_ERR);
+       if (!common)
+               ; /* No common ancestors found. We need a real merge. */
+       else if (!remoteheads->next && !common->next &&
+                       common->item == remoteheads->item) {
+               /*
+                * If head can reach all the merge then we are up to date.
+                * but first the most common case of merging one remote.
+                */
+               finish_up_to_date("Already up-to-date.");
+               return 0;
+       } else if (allow_fast_forward && !remoteheads->next &&
+                       !common->next &&
+                       !hashcmp(common->item->object.sha1, head)) {
+               /* Again the most common case of merging one remote. */
+               struct strbuf msg;
+               struct object *o;
+               char hex[41];
+               strcpy(hex, find_unique_abbrev(head, DEFAULT_ABBREV));
+               printf("Updating %s..%s\n",
+                       hex,
+                       find_unique_abbrev(remoteheads->item->object.sha1,
+                       DEFAULT_ABBREV));
+               refresh_cache(REFRESH_QUIET);
+               strbuf_init(&msg, 0);
+               strbuf_addstr(&msg, "Fast forward");
+               if (have_message)
+                       strbuf_addstr(&msg,
+                               " (no commit created; -m option ignored)");
+               o = peel_to_type(sha1_to_hex(remoteheads->item->object.sha1),
+                       0, NULL, OBJ_COMMIT);
+               if (!o)
+                       return 1;
+               if (checkout_fast_forward(head, remoteheads->item->object.sha1))
+                       return 1;
+               finish(o->sha1, msg.buf);
+               drop_save();
+               return 0;
+       } else if (!remoteheads->next && common->next)
+               ;
+               /*
+                * We are not doing octopus and not fast forward.  Need
+                * a real merge.
+                */
+       else if (!remoteheads->next && !common->next && option_commit) {
+               /*
+                * We are not doing octopus, not fast forward, and have
+                * only one common.
+                */
+               refresh_cache(REFRESH_QUIET);
+               if (allow_trivial) {
+                       /* See if it is really trivial. */
+                       git_committer_info(IDENT_ERROR_ON_NO_NAME);
+                       printf("Trying really trivial in-index merge...\n");
+                       if (!read_tree_trivial(common->item->object.sha1,
+                                       head, remoteheads->item->object.sha1))
+                               return merge_trivial();
+                       printf("Nope.\n");
+               }
+       } else {
+               /*
+                * An octopus.  If we can reach all the remote we are up
+                * to date.
+                */
+               int up_to_date = 1;
+               struct commit_list *j;
+               for (j = remoteheads; j; j = j->next) {
+                       struct commit_list *common_one;
+                       /*
+                        * Here we *have* to calculate the individual
+                        * merge_bases again, otherwise "git merge HEAD^
+                        * HEAD^^" would be missed.
+                        */
+                       common_one = get_merge_bases(lookup_commit(head),
+                               j->item, 1);
+                       if (hashcmp(common_one->item->object.sha1,
+                               j->item->object.sha1)) {
+                               up_to_date = 0;
+                               break;
+                       }
+               }
+               if (up_to_date) {
+                       finish_up_to_date("Already up-to-date. Yeeah!");
+                       return 0;
+               }
+       }
+       /* We are going to make a new commit. */
+       git_committer_info(IDENT_ERROR_ON_NO_NAME);
+       /*
+        * At this point, we need a real merge.  No matter what strategy
+        * we use, it would operate on the index, possibly affecting the
+        * working tree, and when resolved cleanly, have the desired
+        * tree in the index -- this means that the index must be in
+        * sync with the head commit.  The strategies are responsible
+        * to ensure this.
+        */
+       if (use_strategies_nr != 1) {
+               /*
+                * Stash away the local changes so that we can try more
+                * than one.
+                */
+               save_state();
+       } else {
+               memcpy(stash, null_sha1, 20);
+       }
+       for (i = 0; i < use_strategies_nr; i++) {
+               int ret;
+               if (i) {
+                       printf("Rewinding the tree to pristine...\n");
+                       restore_state();
+               }
+               if (use_strategies_nr != 1)
+                       printf("Trying merge strategy %s...\n",
+                               use_strategies[i]->name);
+               /*
+                * Remember which strategy left the state in the working
+                * tree.
+                */
+               wt_strategy = use_strategies[i]->name;
+               ret = try_merge_strategy(use_strategies[i]->name,
+                       common, head_arg);
+               if (!option_commit && !ret) {
+                       merge_was_ok = 1;
+                       /*
+                        * This is necessary here just to avoid writing
+                        * the tree, but later we will *not* exit with
+                        * status code 1 because merge_was_ok is set.
+                        */
+                       ret = 1;
+               }
+               if (ret) {
+                       /*
+                        * The backend exits with 1 when conflicts are
+                        * left to be resolved, with 2 when it does not
+                        * handle the given merge at all.
+                        */
+                       if (ret == 1) {
+                               int cnt = evaluate_result();
+                               if (best_cnt <= 0 || cnt <= best_cnt) {
+                                       best_strategy = use_strategies[i]->name;
+                                       best_cnt = cnt;
+                               }
+                       }
+                       if (merge_was_ok)
+                               break;
+                       else
+                               continue;
+               }
+               /* Automerge succeeded. */
+               write_tree_trivial(result_tree);
+               automerge_was_ok = 1;
+               break;
+       }
+       /*
+        * If we have a resulting tree, that means the strategy module
+        * auto resolved the merge cleanly.
+        */
+       if (automerge_was_ok)
+               return finish_automerge(common, result_tree, wt_strategy);
+       /*
+        * Pick the result from the best strategy and have the user fix
+        * it up.
+        */
+       if (!best_strategy) {
+               restore_state();
+               if (use_strategies_nr > 1)
+                       fprintf(stderr,
+                               "No merge strategy handled the merge.\n");
+               else
+                       fprintf(stderr, "Merge with strategy %s failed.\n",
+                               use_strategies[0]->name);
+               return 2;
+       } else if (best_strategy == wt_strategy)
+               ; /* We already have its result in the working tree. */
+       else {
+               printf("Rewinding the tree to pristine...\n");
+               restore_state();
+               printf("Using the %s to prepare resolving by hand.\n",
+                       best_strategy);
+               try_merge_strategy(best_strategy, common, head_arg);
+       }
+       if (squash)
+               finish(NULL, NULL);
+       else {
+               int fd;
+               struct commit_list *j;
+               for (j = remoteheads; j; j = j->next)
+                       strbuf_addf(&buf, "%s\n",
+                               sha1_to_hex(j->item->object.sha1));
+               fd = open(git_path("MERGE_HEAD"), O_WRONLY | O_CREAT, 0666);
+               if (fd < 0)
+                       die("Could open %s for writing",
+                               git_path("MERGE_HEAD"));
+               if (write_in_full(fd, buf.buf, buf.len) != buf.len)
+                       die("Could not write to %s", git_path("MERGE_HEAD"));
+               close(fd);
+               strbuf_addch(&merge_msg, '\n');
+               fd = open(git_path("MERGE_MSG"), O_WRONLY | O_CREAT, 0666);
+               if (fd < 0)
+                       die("Could open %s for writing", git_path("MERGE_MSG"));
+               if (write_in_full(fd, merge_msg.buf, merge_msg.len) !=
+                       merge_msg.len)
+                       die("Could not write to %s", git_path("MERGE_MSG"));
+               close(fd);
+       }
+       if (merge_was_ok) {
+               fprintf(stderr, "Automatic merge went well; "
+                       "stopped before committing as requested\n");
+               return 0;
+       } else
+               return suggest_conflicts();
+ }
diff --combined cache.h
index a8254e2f9e076b2b69dd214379578e6fc065ddcc,d0d74a3ff880b8550caf72794104fae0f81588aa..a779d9207c8ea4d4e8455a89b17f312e0e71332d
+++ b/cache.h
@@@ -254,6 -254,7 +254,7 @@@ static inline void remove_name_hash(str
  
  #define read_cache() read_index(&the_index)
  #define read_cache_from(path) read_index_from(&the_index, (path))
+ #define read_cache_unmerged() read_index_unmerged(&the_index)
  #define write_cache(newfd, cache, entries) write_index(&the_index, (newfd))
  #define discard_cache() discard_index(&the_index)
  #define unmerged_cache() unmerged_index(&the_index)
@@@ -298,8 -299,8 +299,8 @@@ static inline enum object_type object_t
  #define GRAFT_ENVIRONMENT "GIT_GRAFT_FILE"
  #define TEMPLATE_DIR_ENVIRONMENT "GIT_TEMPLATE_DIR"
  #define CONFIG_ENVIRONMENT "GIT_CONFIG"
 -#define CONFIG_LOCAL_ENVIRONMENT "GIT_CONFIG_LOCAL"
  #define EXEC_PATH_ENVIRONMENT "GIT_EXEC_PATH"
 +#define CEILING_DIRECTORIES_ENVIRONMENT "GIT_CEILING_DIRECTORIES"
  #define GITATTRIBUTES_FILE ".gitattributes"
  #define INFOATTRIBUTES_FILE "info/attributes"
  #define ATTRIBUTE_MACRO_PREFIX "[attr]"
@@@ -356,6 -357,7 +357,7 @@@ extern int init_db(const char *template
  /* Initialize and use the cache information */
  extern int read_index(struct index_state *);
  extern int read_index_from(struct index_state *, const char *path);
+ extern int read_index_unmerged(struct index_state *);
  extern int write_index(const struct index_state *, int newfd);
  extern int discard_index(struct index_state *);
  extern int unmerged_index(const struct index_state *);
@@@ -522,13 -524,11 +524,13 @@@ int safe_create_leading_directories_con
  char *enter_repo(char *path, int strict);
  static inline int is_absolute_path(const char *path)
  {
 -      return path[0] == '/';
 +      return path[0] == '/' || has_dos_drive_prefix(path);
  }
  const char *make_absolute_path(const char *path);
  const char *make_nonrelative_path(const char *path);
  const char *make_relative_path(const char *abs, const char *base);
 +int normalize_absolute_path(char *buf, const char *path);
 +int longest_ancestor_length(const char *path, const char *prefix_list);
  
  /* Read and unpack a sha1 file into memory, write memory to a sha1 file */
  extern int sha1_object_info(const unsigned char *, unsigned long *);
@@@ -538,9 -538,6 +540,9 @@@ extern int write_sha1_file(void *buf, u
  extern int pretend_sha1_file(void *, unsigned long, enum object_type, unsigned char *);
  extern int force_object_loose(const unsigned char *sha1, time_t mtime);
  
 +/* just like read_sha1_file(), but non fatal in presence of bad objects */
 +extern void *read_object(const unsigned char *sha1, enum object_type *type, unsigned long *size);
 +
  extern int check_sha1_signature(const unsigned char *sha1, void *buf, unsigned long size, const char *type);
  
  extern int move_temp_to_file(const char *tmpfile, const char *filename);
@@@ -748,7 -745,6 +750,7 @@@ extern int check_repository_format_vers
  extern int git_config_system(void);
  extern int git_config_global(void);
  extern int config_error_nonbool(const char *);
 +extern const char *config_exclusive_filename;
  
  #define MAX_GITNAME (1000)
  extern char git_default_email[MAX_GITNAME];
@@@ -825,11 -821,11 +827,11 @@@ void shift_tree(const unsigned char *, 
  extern unsigned whitespace_rule_cfg;
  extern unsigned whitespace_rule(const char *);
  extern unsigned parse_whitespace_rule(const char *);
 -extern unsigned check_and_emit_line(const char *line, int len, unsigned ws_rule,
 -    FILE *stream, const char *set,
 -    const char *reset, const char *ws);
 +extern unsigned ws_check(const char *line, int len, unsigned ws_rule);
 +extern void ws_check_emit(const char *line, int len, unsigned ws_rule, FILE *stream, const char *set, const char *reset, const char *ws);
  extern char *whitespace_error_string(unsigned ws);
  extern int ws_fix_copy(char *, const char *, int, unsigned, int *);
 +extern int ws_blank_line(const char *line, int len, unsigned ws_rule);
  
  /* ls-files */
  int pathspec_match(const char **spec, char *matched, const char *filename, int skiplen);
@@@ -837,5 -833,6 +839,6 @@@ int report_path_error(const char *ps_ma
  void overlay_tree_on_cache(const char *tree_name, const char *prefix);
  
  char *alias_lookup(const char *alias);
+ int split_cmdline(char *cmdline, const char ***argv);
  
  #endif /* CACHE_H */
diff --combined commit.h
index fda7ad03c0b1d0f2c2cd1e758dbaecf47742c576,2acfc79d3483b4c83c1c181a8ac1505393e96ee5..77de9621d9c926c6fb8a2bf9ca81c6c376a2ad41
+++ b/commit.h
@@@ -41,6 -41,7 +41,7 @@@ int parse_commit_buffer(struct commit *
  int parse_commit(struct commit *item);
  
  struct commit_list * commit_list_insert(struct commit *item, struct commit_list **list_p);
+ unsigned commit_list_count(const struct commit_list *l);
  struct commit_list * insert_by_date(struct commit *item, struct commit_list **list);
  
  void free_commit_list(struct commit_list *list);
@@@ -120,6 -121,7 +121,7 @@@ int read_graft_file(const char *graft_f
  struct commit_graft *lookup_commit_graft(const unsigned char *sha1);
  
  extern struct commit_list *get_merge_bases(struct commit *rev1, struct commit *rev2, int cleanup);
+ extern struct commit_list *get_octopus_merge_bases(struct commit_list *in);
  
  extern int register_shallow(const unsigned char *sha1);
  extern int unregister_shallow(const unsigned char *sha1);
@@@ -131,10 -133,13 +133,12 @@@ extern struct commit_list *get_shallow_
  int in_merge_bases(struct commit *, struct commit **, int);
  
  extern int interactive_add(int argc, const char **argv, const char *prefix);
 -extern int rerere(void);
  
  static inline int single_parent(struct commit *commit)
  {
        return commit->parents && !commit->parents->next;
  }
  
+ struct commit_list *reduce_heads(struct commit_list *heads);
  #endif /* COMMIT_H */
diff --combined git-compat-util.h
index 8c7e11473390c14956e43843c17a2d85a336a087,31edc98f30e2b5bb5504f49d2cad013f5dbd9e78..cf89cdf4598b3796724a85aa707f740245155cdc
  #include <sys/time.h>
  #include <time.h>
  #include <signal.h>
 -#include <sys/wait.h>
  #include <fnmatch.h>
 +#include <assert.h>
 +#include <regex.h>
 +#include <utime.h>
 +#ifndef __MINGW32__
 +#include <sys/wait.h>
  #include <sys/poll.h>
  #include <sys/socket.h>
  #include <sys/ioctl.h>
 -#include <utime.h>
  #ifndef NO_SYS_SELECT_H
  #include <sys/select.h>
  #endif
 -#include <assert.h>
 -#include <regex.h>
  #include <netinet/in.h>
  #include <netinet/tcp.h>
  #include <arpa/inet.h>
  #include <grp.h>
  #define _ALL_SOURCE 1
  #endif
 +#else         /* __MINGW32__ */
 +/* pull in Windows compatibility stuff */
 +#include "compat/mingw.h"
 +#endif        /* __MINGW32__ */
  
  #ifndef NO_ICONV
  #include <iconv.h>
  #define PRIuMAX "llu"
  #endif
  
 +#ifndef PRIu32
 +#define PRIu32 "u"
 +#endif
 +
 +#ifndef PRIx32
 +#define PRIx32 "x"
 +#endif
 +
 +#ifndef PATH_SEP
 +#define PATH_SEP ':'
 +#endif
 +
 +#ifndef STRIP_EXTENSION
 +#define STRIP_EXTENSION ""
 +#endif
 +
 +#ifndef has_dos_drive_prefix
 +#define has_dos_drive_prefix(path) 0
 +#endif
 +
 +#ifndef is_dir_sep
 +#define is_dir_sep(c) ((c) == '/')
 +#endif
 +
  #ifdef __GNUC__
  #define NORETURN __attribute__((__noreturn__))
  #else
@@@ -155,8 -126,13 +155,14 @@@ extern void set_error_routine(void (*ro
  extern void set_warn_routine(void (*routine)(const char *warn, va_list params));
  
  extern int prefixcmp(const char *str, const char *prefix);
 +extern time_t tm_to_time_t(const struct tm *tm);
  
+ static inline const char *skip_prefix(const char *str, const char *prefix)
+ {
+       size_t len = strlen(prefix);
+       return strncmp(str, prefix, len) ? NULL : str + len;
+ }
  #ifdef NO_MMAP
  
  #ifndef PROT_READ
@@@ -193,12 -169,6 +199,12 @@@ extern int git_munmap(void *start, size
  #define pread git_pread
  extern ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
  #endif
 +/*
 + * Forward decl that will remind us if its twin in cache.h changes.
 + * This function is used in compat/pread.c.  But we can't include
 + * cache.h there.
 + */
 +extern ssize_t read_in_full(int fd, void *buf, size_t count);
  
  #ifdef NO_SETENV
  #define setenv gitsetenv
diff --combined git.c
index 7075533aa7243abacf100cb8a8987284d5d144de,770aadd0a4ad358ec3dc290eed417df1698fd18e..74ea0e6cc52f627df1bf018770aec67584325ab5
--- 1/git.c
--- 2/git.c
+++ b/git.c
@@@ -9,43 -9,6 +9,43 @@@ const char git_usage_string[] 
  const char git_more_info_string[] =
        "See 'git help COMMAND' for more information on a specific command.";
  
 +static int use_pager = -1;
 +struct pager_config {
 +      const char *cmd;
 +      int val;
 +};
 +
 +static int pager_command_config(const char *var, const char *value, void *data)
 +{
 +      struct pager_config *c = data;
 +      if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
 +              c->val = git_config_bool(var, value);
 +      return 0;
 +}
 +
 +/* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
 +int check_pager_config(const char *cmd)
 +{
 +      struct pager_config c;
 +      c.cmd = cmd;
 +      c.val = -1;
 +      git_config(pager_command_config, &c);
 +      return c.val;
 +}
 +
 +static void commit_pager_choice(void) {
 +      switch (use_pager) {
 +      case 0:
 +              setenv("GIT_PAGER", "cat", 1);
 +              break;
 +      case 1:
 +              setup_pager();
 +              break;
 +      default:
 +              break;
 +      }
 +}
 +
  static int handle_options(const char*** argv, int* argc, int* envchanged)
  {
        int handled = 0;
@@@ -75,9 -38,9 +75,9 @@@
                                exit(0);
                        }
                } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
 -                      setup_pager();
 +                      use_pager = 1;
                } else if (!strcmp(cmd, "--no-pager")) {
 -                      setenv("GIT_PAGER", "cat", 1);
 +                      use_pager = 0;
                        if (envchanged)
                                *envchanged = 1;
                } else if (!strcmp(cmd, "--git-dir")) {
        return handled;
  }
  
- static int split_cmdline(char *cmdline, const char ***argv)
- {
-       int src, dst, count = 0, size = 16;
-       char quoted = 0;
-       *argv = xmalloc(sizeof(char*) * size);
-       /* split alias_string */
-       (*argv)[count++] = cmdline;
-       for (src = dst = 0; cmdline[src];) {
-               char c = cmdline[src];
-               if (!quoted && isspace(c)) {
-                       cmdline[dst++] = 0;
-                       while (cmdline[++src]
-                                       && isspace(cmdline[src]))
-                               ; /* skip */
-                       if (count >= size) {
-                               size += 16;
-                               *argv = xrealloc(*argv, sizeof(char*) * size);
-                       }
-                       (*argv)[count++] = cmdline + dst;
-               } else if(!quoted && (c == '\'' || c == '"')) {
-                       quoted = c;
-                       src++;
-               } else if (c == quoted) {
-                       quoted = 0;
-                       src++;
-               } else {
-                       if (c == '\\' && quoted != '\'') {
-                               src++;
-                               c = cmdline[src];
-                               if (!c) {
-                                       free(*argv);
-                                       *argv = NULL;
-                                       return error("cmdline ends with \\");
-                               }
-                       }
-                       cmdline[dst++] = c;
-                       src++;
-               }
-       }
-       cmdline[dst] = 0;
-       if (quoted) {
-               free(*argv);
-               *argv = NULL;
-               return error("unclosed quote");
-       }
-       return count;
- }
  static int handle_alias(int *argcp, const char ***argv)
  {
        int envchanged = 0, ret = 0, saved_errno = errno;
@@@ -279,13 -189,8 +226,13 @@@ static int run_command(struct cmd_struc
        prefix = NULL;
        if (p->option & RUN_SETUP)
                prefix = setup_git_directory();
 -      if (p->option & USE_PAGER)
 -              setup_pager();
 +
 +      if (use_pager == -1 && p->option & RUN_SETUP)
 +              use_pager = check_pager_config(p->cmd);
 +      if (use_pager == -1 && p->option & USE_PAGER)
 +              use_pager = 1;
 +      commit_pager_choice();
 +
        if (p->option & NEED_WORK_TREE)
                setup_work_tree();
  
@@@ -366,6 -271,7 +313,7 @@@ static void handle_internal_command(in
                { "ls-remote", cmd_ls_remote },
                { "mailinfo", cmd_mailinfo },
                { "mailsplit", cmd_mailsplit },
+               { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
                { "merge-base", cmd_merge_base, RUN_SETUP },
                { "merge-file", cmd_merge_file },
                { "merge-ours", cmd_merge_ours, RUN_SETUP },
                { "pack-refs", cmd_pack_refs, RUN_SETUP },
        };
        int i;
 +      static const char ext[] = STRIP_EXTENSION;
 +
 +      if (sizeof(ext) > 1) {
 +              i = strlen(argv[0]) - strlen(ext);
 +              if (i > 0 && !strcmp(argv[0] + i, ext)) {
 +                      char *argv0 = strdup(argv[0]);
 +                      argv[0] = cmd = argv0;
 +                      argv0[i] = '\0';
 +              }
 +      }
  
        /* Turn "git cmd --help" into "git help cmd" */
        if (argc > 1 && !strcmp(argv[1], "--help")) {
        }
  }
  
 +static void execv_dashed_external(const char **argv)
 +{
 +      struct strbuf cmd;
 +      const char *tmp;
 +
 +      strbuf_init(&cmd, 0);
 +      strbuf_addf(&cmd, "git-%s", argv[0]);
 +
 +      /*
 +       * argv[0] must be the git command, but the argv array
 +       * belongs to the caller, and may be reused in
 +       * subsequent loop iterations. Save argv[0] and
 +       * restore it on error.
 +       */
 +      tmp = argv[0];
 +      argv[0] = cmd.buf;
 +
 +      trace_argv_printf(argv, "trace: exec:");
 +
 +      /* execvp() can only ever return if it fails */
 +      execvp(cmd.buf, (char **)argv);
 +
 +      trace_printf("trace: exec failed: %s\n", strerror(errno));
 +
 +      argv[0] = tmp;
 +
 +      strbuf_release(&cmd);
 +}
 +
 +
  int main(int argc, const char **argv)
  {
 -      const char *cmd = argv[0] ? argv[0] : "git-help";
 -      char *slash = strrchr(cmd, '/');
 +      const char *cmd = argv[0] && *argv[0] ? argv[0] : "git-help";
 +      char *slash = (char *)cmd + strlen(cmd);
        const char *cmd_path = NULL;
        int done_alias = 0;
  
         * name, and the dirname as the default exec_path
         * if we don't have anything better.
         */
 -      if (slash) {
 +      do
 +              --slash;
 +      while (cmd <= slash && !is_dir_sep(*slash));
 +      if (cmd <= slash) {
                *slash++ = 0;
                cmd_path = cmd;
                cmd = slash;
        argv++;
        argc--;
        handle_options(&argv, &argc, NULL);
 +      commit_pager_choice();
        if (argc > 0) {
                if (!prefixcmp(argv[0], "--"))
                        argv[0] += 2;
                handle_internal_command(argc, argv);
  
                /* .. then try the external ones */
 -              execv_git_cmd(argv);
 +              execv_dashed_external(argv);
  
                /* It could be an alias -- this works around the insanity
                 * of overriding "git log" with "git show" by having
diff --combined parse-options.c
index ae88885d4da573c85dbfbeea3061f3b026223710,bbc3ca4a9ffc0c3be829b074cadb2b2a82e43f02..2fd5edbf53546ac449a077439aa59ca5dd992274
@@@ -1,16 -1,27 +1,10 @@@
  #include "git-compat-util.h"
  #include "parse-options.h"
 +#include "cache.h"
  
  #define OPT_SHORT 1
  #define OPT_UNSET 2
  
- static inline const char *skip_prefix(const char *str, const char *prefix)
 -struct optparse_t {
 -      const char **argv;
 -      const char **out;
 -      int argc, cpidx;
 -      const char *opt;
 -};
 -
 -static inline const char *get_arg(struct optparse_t *p)
--{
-       size_t len = strlen(prefix);
-       return strncmp(str, prefix, len) ? NULL : str + len;
 -      if (p->opt) {
 -              const char *res = p->opt;
 -              p->opt = NULL;
 -              return res;
 -      }
 -      p->argc--;
 -      return *++p->argv;
--}
--
  static int opterror(const struct option *opt, const char *reason, int flags)
  {
        if (flags & OPT_SHORT)
        return error("option `%s' %s", opt->long_name, reason);
  }
  
 -static int get_value(struct optparse_t *p,
 -                     const struct option *opt, int flags)
 +static int get_arg(struct parse_opt_ctx_t *p, const struct option *opt,
 +                 int flags, const char **arg)
 +{
 +      if (p->opt) {
 +              *arg = p->opt;
 +              p->opt = NULL;
 +      } else if (p->argc == 1 && (opt->flags & PARSE_OPT_LASTARG_DEFAULT)) {
 +              *arg = (const char *)opt->defval;
 +      } else if (p->argc) {
 +              p->argc--;
 +              *arg = *++p->argv;
 +      } else
 +              return opterror(opt, "requires a value", flags);
 +      return 0;
 +}
 +
 +static int get_value(struct parse_opt_ctx_t *p,
 +                   const struct option *opt, int flags)
  {
        const char *s, *arg;
        const int unset = flags & OPT_UNSET;
@@@ -63,6 -58,7 +57,6 @@@
                }
        }
  
 -      arg = p->opt ? p->opt : (p->argc > 1 ? p->argv[1] : NULL);
        switch (opt->type) {
        case OPTION_BIT:
                if (unset)
                return 0;
  
        case OPTION_STRING:
 -              if (unset) {
 +              if (unset)
                        *(const char **)opt->value = NULL;
 -                      return 0;
 -              }
 -              if (opt->flags & PARSE_OPT_OPTARG && !p->opt) {
 +              else if (opt->flags & PARSE_OPT_OPTARG && !p->opt)
                        *(const char **)opt->value = (const char *)opt->defval;
 -                      return 0;
 -              }
 -              if (!arg)
 -                      return opterror(opt, "requires a value", flags);
 -              *(const char **)opt->value = get_arg(p);
 +              else
 +                      return get_arg(p, opt, flags, (const char **)opt->value);
                return 0;
  
        case OPTION_CALLBACK:
                if (unset)
 -                      return (*opt->callback)(opt, NULL, 1);
 +                      return (*opt->callback)(opt, NULL, 1) ? (-1) : 0;
                if (opt->flags & PARSE_OPT_NOARG)
 -                      return (*opt->callback)(opt, NULL, 0);
 +                      return (*opt->callback)(opt, NULL, 0) ? (-1) : 0;
                if (opt->flags & PARSE_OPT_OPTARG && !p->opt)
 -                      return (*opt->callback)(opt, NULL, 0);
 -              if (!arg)
 -                      return opterror(opt, "requires a value", flags);
 -              return (*opt->callback)(opt, get_arg(p), 0);
 +                      return (*opt->callback)(opt, NULL, 0) ? (-1) : 0;
 +              if (get_arg(p, opt, flags, &arg))
 +                      return -1;
 +              return (*opt->callback)(opt, arg, 0) ? (-1) : 0;
  
        case OPTION_INTEGER:
                if (unset) {
                        *(int *)opt->value = opt->defval;
                        return 0;
                }
 -              if (!arg)
 -                      return opterror(opt, "requires a value", flags);
 -              *(int *)opt->value = strtol(get_arg(p), (char **)&s, 10);
 +              if (get_arg(p, opt, flags, &arg))
 +                      return -1;
 +              *(int *)opt->value = strtol(arg, (char **)&s, 10);
                if (*s)
                        return opterror(opt, "expects a numerical value", flags);
                return 0;
        }
  }
  
 -static int parse_short_opt(struct optparse_t *p, const struct option *options)
 +static int parse_short_opt(struct parse_opt_ctx_t *p, const struct option *options)
  {
        for (; options->type != OPTION_END; options++) {
                if (options->short_name == *p->opt) {
                        return get_value(p, options, OPT_SHORT);
                }
        }
 -      return error("unknown switch `%c'", *p->opt);
 +      return -2;
  }
  
 -static int parse_long_opt(struct optparse_t *p, const char *arg,
 +static int parse_long_opt(struct parse_opt_ctx_t *p, const char *arg,
                            const struct option *options)
  {
        const char *arg_end = strchr(arg, '=');
@@@ -217,7 -218,7 +211,7 @@@ is_abbreviated
                        abbrev_option->long_name);
        if (abbrev_option)
                return get_value(p, abbrev_option, abbrev_flags);
 -      return error("unknown option `%s'", arg);
 +      return -2;
  }
  
  void check_typos(const char *arg, const struct option *options)
        }
  }
  
 -static NORETURN void usage_with_options_internal(const char * const *,
 -                                                 const struct option *, int);
 +void parse_options_start(struct parse_opt_ctx_t *ctx,
 +                       int argc, const char **argv, int flags)
 +{
 +      memset(ctx, 0, sizeof(*ctx));
 +      ctx->argc = argc - 1;
 +      ctx->argv = argv + 1;
 +      ctx->out  = argv;
 +      ctx->cpidx = ((flags & PARSE_OPT_KEEP_ARGV0) != 0);
 +      ctx->flags = flags;
 +}
  
 -int parse_options(int argc, const char **argv, const struct option *options,
 -                  const char * const usagestr[], int flags)
 +static int usage_with_options_internal(const char * const *,
 +                                     const struct option *, int);
 +
 +int parse_options_step(struct parse_opt_ctx_t *ctx,
 +                     const struct option *options,
 +                     const char * const usagestr[])
  {
 -      struct optparse_t args = { argv + 1, argv, argc - 1, 0, NULL };
 +      /* we must reset ->opt, unknown short option leave it dangling */
 +      ctx->opt = NULL;
  
 -      for (; args.argc; args.argc--, args.argv++) {
 -              const char *arg = args.argv[0];
 +      for (; ctx->argc; ctx->argc--, ctx->argv++) {
 +              const char *arg = ctx->argv[0];
  
                if (*arg != '-' || !arg[1]) {
 -                      if (flags & PARSE_OPT_STOP_AT_NON_OPTION)
 +                      if (ctx->flags & PARSE_OPT_STOP_AT_NON_OPTION)
                                break;
 -                      args.out[args.cpidx++] = args.argv[0];
 +                      ctx->out[ctx->cpidx++] = ctx->argv[0];
                        continue;
                }
  
                if (arg[1] != '-') {
 -                      args.opt = arg + 1;
 -                      if (*args.opt == 'h')
 -                              usage_with_options(usagestr, options);
 -                      if (parse_short_opt(&args, options) < 0)
 -                              usage_with_options(usagestr, options);
 -                      if (args.opt)
 +                      ctx->opt = arg + 1;
 +                      if (*ctx->opt == 'h')
 +                              return parse_options_usage(usagestr, options);
 +                      switch (parse_short_opt(ctx, options)) {
 +                      case -1:
 +                              return parse_options_usage(usagestr, options);
 +                      case -2:
 +                              return PARSE_OPT_UNKNOWN;
 +                      }
 +                      if (ctx->opt)
                                check_typos(arg + 1, options);
 -                      while (args.opt) {
 -                              if (*args.opt == 'h')
 -                                      usage_with_options(usagestr, options);
 -                              if (parse_short_opt(&args, options) < 0)
 -                                      usage_with_options(usagestr, options);
 +                      while (ctx->opt) {
 +                              if (*ctx->opt == 'h')
 +                                      return parse_options_usage(usagestr, options);
 +                              switch (parse_short_opt(ctx, options)) {
 +                              case -1:
 +                                      return parse_options_usage(usagestr, options);
 +                              case -2:
 +                                      /* fake a short option thing to hide the fact that we may have
 +                                       * started to parse aggregated stuff
 +                                       *
 +                                       * This is leaky, too bad.
 +                                       */
 +                                      ctx->argv[0] = xstrdup(ctx->opt - 1);
 +                                      *(char *)ctx->argv[0] = '-';
 +                                      return PARSE_OPT_UNKNOWN;
 +                              }
                        }
                        continue;
                }
  
                if (!arg[2]) { /* "--" */
 -                      if (!(flags & PARSE_OPT_KEEP_DASHDASH)) {
 -                              args.argc--;
 -                              args.argv++;
 +                      if (!(ctx->flags & PARSE_OPT_KEEP_DASHDASH)) {
 +                              ctx->argc--;
 +                              ctx->argv++;
                        }
                        break;
                }
  
                if (!strcmp(arg + 2, "help-all"))
 -                      usage_with_options_internal(usagestr, options, 1);
 +                      return usage_with_options_internal(usagestr, options, 1);
                if (!strcmp(arg + 2, "help"))
 -                      usage_with_options(usagestr, options);
 -              if (parse_long_opt(&args, arg + 2, options))
 -                      usage_with_options(usagestr, options);
 +                      return parse_options_usage(usagestr, options);
 +              switch (parse_long_opt(ctx, arg + 2, options)) {
 +              case -1:
 +                      return parse_options_usage(usagestr, options);
 +              case -2:
 +                      return PARSE_OPT_UNKNOWN;
 +              }
        }
 +      return PARSE_OPT_DONE;
 +}
  
 -      memmove(args.out + args.cpidx, args.argv, args.argc * sizeof(*args.out));
 -      args.out[args.cpidx + args.argc] = NULL;
 -      return args.cpidx + args.argc;
 +int parse_options_end(struct parse_opt_ctx_t *ctx)
 +{
 +      memmove(ctx->out + ctx->cpidx, ctx->argv, ctx->argc * sizeof(*ctx->out));
 +      ctx->out[ctx->cpidx + ctx->argc] = NULL;
 +      return ctx->cpidx + ctx->argc;
 +}
 +
 +int parse_options(int argc, const char **argv, const struct option *options,
 +                const char * const usagestr[], int flags)
 +{
 +      struct parse_opt_ctx_t ctx;
 +
 +      parse_options_start(&ctx, argc, argv, flags);
 +      switch (parse_options_step(&ctx, options, usagestr)) {
 +      case PARSE_OPT_HELP:
 +              exit(129);
 +      case PARSE_OPT_DONE:
 +              break;
 +      default: /* PARSE_OPT_UNKNOWN */
 +              if (ctx.argv[0][1] == '-') {
 +                      error("unknown option `%s'", ctx.argv[0] + 2);
 +              } else {
 +                      error("unknown switch `%c'", *ctx.opt);
 +              }
 +              usage_with_options(usagestr, options);
 +      }
 +
 +      return parse_options_end(&ctx);
  }
  
  #define USAGE_OPTS_WIDTH 24
  #define USAGE_GAP         2
  
 -void usage_with_options_internal(const char * const *usagestr,
 -                                 const struct option *opts, int full)
 +int usage_with_options_internal(const char * const *usagestr,
 +                              const struct option *opts, int full)
  {
        fprintf(stderr, "usage: %s\n", *usagestr++);
        while (*usagestr && **usagestr)
        }
        fputc('\n', stderr);
  
 -      exit(129);
 +      return PARSE_OPT_HELP;
  }
  
  void usage_with_options(const char * const *usagestr,
 -                        const struct option *opts)
 +                      const struct option *opts)
  {
        usage_with_options_internal(usagestr, opts, 0);
 +      exit(129);
  }
  
 +int parse_options_usage(const char * const *usagestr,
 +                      const struct option *opts)
 +{
 +      return usage_with_options_internal(usagestr, opts, 0);
 +}
 +
 +
  /*----- some often used options -----*/
  #include "cache.h"