Make "git reset" a builtin.

This replaces the script "git-reset.sh" with "builtin-reset.c".

A few git commands used in the script are called from the builtin also:
"ls-files" to check for unmerged files, "read-tree" for resetting
the index file in "mixed" and "hard" resets, and "update-index" to
refresh at the end in the "mixed" reset and also for the option that
gets selected paths into the index.

The reset option with paths was implemented by Johannes Schindelin.

Since the option that gets selected paths into the index is not
a "reset" like the others because it does not change the HEAD at all,
now the command is showing a warning when the "--mixed" option
is supplied for that purpose.

The following table shows the behaviour of "git reset" for
the different supported options, where X means "changing"
the HEAD, index or working tree:

reset:  --soft  --mixed  --hard  -- <paths>
HEAD       X       X        X        -
index      -       X        X        X
files      -       -        X        -

Signed-off-by: Carlos Rica <jasampler@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Makefile b/Makefile
index 78cdaa155ba424475fe091cd19cf212e32fcfc2f..e6740fc3928c239f0f16c10c661d190399882ca0 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -208,7 +208,7 @@ SCRIPT_SH = \
        git-ls-remote.sh \
        git-merge-one-file.sh git-mergetool.sh git-parse-remote.sh \
        git-pull.sh git-rebase.sh git-rebase--interactive.sh \
-       git-repack.sh git-request-pull.sh git-reset.sh \
+       git-repack.sh git-request-pull.sh \
        git-sh-setup.sh \
        git-am.sh \
        git-merge.sh git-merge-stupid.sh git-merge-octopus.sh \
@@ -355,6 +355,7 @@ BUILTIN_OBJS = \
        builtin-reflog.o \
        builtin-config.o \
        builtin-rerere.o \
+       builtin-reset.o \
        builtin-rev-list.o \
        builtin-rev-parse.o \
        builtin-revert.o \

diff --git a/builtin-reset.c b/builtin-reset.c
new file mode 100644 (file)
index 0000000..99d5c08
--- /dev/null
+++ b/builtin-reset.c
@@ -0,0 +1,279 @@
+/*
+ * "git reset" builtin command
+ *
+ * Copyright (c) 2007 Carlos Rica
+ *
+ * Based on git-reset.sh, which is
+ *
+ * Copyright (c) 2005, 2006 Linus Torvalds and Junio C Hamano
+ */
+#include "cache.h"
+#include "tag.h"
+#include "object.h"
+#include "commit.h"
+#include "run-command.h"
+#include "refs.h"
+#include "diff.h"
+#include "diffcore.h"
+#include "tree.h"
+
+static const char builtin_reset_usage[] =
+"git-reset [--mixed | --soft | --hard]  [<commit-ish>] [ [--] <paths>...]";
+
+static char *args_to_str(const char **argv)
+{
+       char *buf = NULL;
+       unsigned long len, space = 0, nr = 0;
+
+       for (; *argv; argv++) {
+               len = strlen(*argv);
+               ALLOC_GROW(buf, nr + 1 + len, space);
+               if (nr)
+                       buf[nr++] = ' ';
+               memcpy(buf + nr, *argv, len);
+               nr += len;
+       }
+       ALLOC_GROW(buf, nr + 1, space);
+       buf[nr] = '\0';
+
+       return buf;
+}
+
+static inline int is_merge(void)
+{
+       return !access(git_path("MERGE_HEAD"), F_OK);
+}
+
+static int unmerged_files(void)
+{
+       char b;
+       ssize_t len;
+       struct child_process cmd;
+       const char *argv_ls_files[] = {"ls-files", "--unmerged", NULL};
+
+       memset(&cmd, 0, sizeof(cmd));
+       cmd.argv = argv_ls_files;
+       cmd.git_cmd = 1;
+       cmd.out = -1;
+
+       if (start_command(&cmd))
+               die("Could not run sub-command: git ls-files");
+
+       len = xread(cmd.out, &b, 1);
+       if (len < 0)
+               die("Could not read output from git ls-files: %s",
+                                               strerror(errno));
+       finish_command(&cmd);
+
+       return len;
+}
+
+static int reset_index_file(const unsigned char *sha1, int is_hard_reset)
+{
+       int i = 0;
+       const char *args[6];
+
+       args[i++] = "read-tree";
+       args[i++] = "-v";
+       args[i++] = "--reset";
+       if (is_hard_reset)
+               args[i++] = "-u";
+       args[i++] = sha1_to_hex(sha1);
+       args[i] = NULL;
+
+       return run_command_v_opt(args, RUN_GIT_CMD);
+}
+
+static void print_new_head_line(struct commit *commit)
+{
+       const char *hex, *dots = "...", *body;
+
+       hex = find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV);
+       if (!hex) {
+               hex = sha1_to_hex(commit->object.sha1);
+               dots = "";
+       }
+       printf("HEAD is now at %s%s", hex, dots);
+       body = strstr(commit->buffer, "\n\n");
+       if (body) {
+               const char *eol;
+               size_t len;
+               body += 2;
+               eol = strchr(body, '\n');
+               len = eol ? eol - body : strlen(body);
+               printf(" %.*s\n", (int) len, body);
+       }
+       else
+               printf("\n");
+}
+
+static int update_index_refresh(void)
+{
+       const char *argv_update_index[] = {"update-index", "--refresh", NULL};
+       return run_command_v_opt(argv_update_index, RUN_GIT_CMD);
+}
+
+static void update_index_from_diff(struct diff_queue_struct *q,
+               struct diff_options *opt, void *data)
+{
+       int i;
+
+       /* do_diff_cache() mangled the index */
+       discard_cache();
+       read_cache();
+
+       for (i = 0; i < q->nr; i++) {
+               struct diff_filespec *one = q->queue[i]->one;
+               if (one->mode) {
+                       struct cache_entry *ce;
+                       ce = make_cache_entry(one->mode, one->sha1, one->path,
+                               0, 0);
+                       add_cache_entry(ce, ADD_CACHE_OK_TO_ADD |
+                               ADD_CACHE_OK_TO_REPLACE);
+               } else
+                       remove_file_from_cache(one->path);
+       }
+}
+
+static int read_from_tree(const char *prefix, const char **argv,
+               unsigned char *tree_sha1)
+{
+        struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
+       int index_fd;
+       struct diff_options opt;
+
+       memset(&opt, 0, sizeof(opt));
+       diff_tree_setup_paths(get_pathspec(prefix, (const char **)argv), &opt);
+       opt.output_format = DIFF_FORMAT_CALLBACK;
+       opt.format_callback = update_index_from_diff;
+
+       index_fd = hold_locked_index(lock, 1);
+       read_cache();
+       if (do_diff_cache(tree_sha1, &opt))
+               return 1;
+       diffcore_std(&opt);
+       diff_flush(&opt);
+       return write_cache(index_fd, active_cache, active_nr) ||
+               close(index_fd) ||
+               commit_locked_index(lock);
+}
+
+static void prepend_reflog_action(const char *action, char *buf, size_t size)
+{
+       const char *sep = ": ";
+       const char *rla = getenv("GIT_REFLOG_ACTION");
+       if (!rla)
+               rla = sep = "";
+       if (snprintf(buf, size, "%s%s%s", rla, sep, action) >= size)
+               warning("Reflog action message too long: %.*s...", 50, buf);
+}
+
+enum reset_type { MIXED, SOFT, HARD, NONE };
+static char *reset_type_names[] = { "mixed", "soft", "hard", NULL };
+
+int cmd_reset(int argc, const char **argv, const char *prefix)
+{
+       int i = 1, reset_type = NONE, update_ref_status = 0;
+       const char *rev = "HEAD";
+       unsigned char sha1[20], *orig = NULL, sha1_orig[20],
+                               *old_orig = NULL, sha1_old_orig[20];
+       struct commit *commit;
+       char *reflog_action, msg[1024];
+
+       git_config(git_default_config);
+
+       reflog_action = args_to_str(argv);
+       setenv("GIT_REFLOG_ACTION", reflog_action, 0);
+
+       if (i < argc) {
+               if (!strcmp(argv[i], "--mixed")) {
+                       reset_type = MIXED;
+                       i++;
+               }
+               else if (!strcmp(argv[i], "--soft")) {
+                       reset_type = SOFT;
+                       i++;
+               }
+               else if (!strcmp(argv[i], "--hard")) {
+                       reset_type = HARD;
+                       i++;
+               }
+       }
+
+       if (i < argc && argv[i][0] != '-')
+               rev = argv[i++];
+
+       if (get_sha1(rev, sha1))
+               die("Failed to resolve '%s' as a valid ref.", rev);
+
+       commit = lookup_commit_reference(sha1);
+       if (!commit)
+               die("Could not parse object '%s'.", rev);
+       hashcpy(sha1, commit->object.sha1);
+
+       if (i < argc && !strcmp(argv[i], "--"))
+               i++;
+       else if (i < argc && argv[i][0] == '-')
+               usage(builtin_reset_usage);
+
+       /* git reset tree [--] paths... can be used to
+        * load chosen paths from the tree into the index without
+        * affecting the working tree nor HEAD. */
+       if (i < argc) {
+               if (reset_type == MIXED)
+                       warning("--mixed option is deprecated with paths.");
+               else if (reset_type != NONE)
+                       die("Cannot do %s reset with paths.",
+                                       reset_type_names[reset_type]);
+               if (read_from_tree(prefix, argv + i, sha1))
+                       return 1;
+               return update_index_refresh() ? 1 : 0;
+       }
+       if (reset_type == NONE)
+               reset_type = MIXED; /* by default */
+
+       /* Soft reset does not touch the index file nor the working tree
+        * at all, but requires them in a good order.  Other resets reset
+        * the index file to the tree object we are switching to. */
+       if (reset_type == SOFT) {
+               if (is_merge() || unmerged_files())
+                       die("Cannot do a soft reset in the middle of a merge.");
+       }
+       else if (reset_index_file(sha1, (reset_type == HARD)))
+               die("Could not reset index file to revision '%s'.", rev);
+
+       /* Any resets update HEAD to the head being switched to,
+        * saving the previous head in ORIG_HEAD before. */
+       if (!get_sha1("ORIG_HEAD", sha1_old_orig))
+               old_orig = sha1_old_orig;
+       if (!get_sha1("HEAD", sha1_orig)) {
+               orig = sha1_orig;
+               prepend_reflog_action("updating ORIG_HEAD", msg, sizeof(msg));
+               update_ref(msg, "ORIG_HEAD", orig, old_orig, 0, MSG_ON_ERR);
+       }
+       else if (old_orig)
+               delete_ref("ORIG_HEAD", old_orig);
+       prepend_reflog_action("updating HEAD", msg, sizeof(msg));
+       update_ref_status = update_ref(msg, "HEAD", sha1, orig, 0, MSG_ON_ERR);
+
+       switch (reset_type) {
+       case HARD:
+               if (!update_ref_status)
+                       print_new_head_line(commit);
+               break;
+       case SOFT: /* Nothing else to do. */
+               break;
+       case MIXED: /* Report what has not been updated. */
+               update_index_refresh();
+               break;
+       }
+
+       unlink(git_path("MERGE_HEAD"));
+       unlink(git_path("rr-cache/MERGE_RR"));
+       unlink(git_path("MERGE_MSG"));
+       unlink(git_path("SQUASH_MSG"));
+
+       free(reflog_action);
+
+       return update_ref_status;
+}

diff --git a/builtin.h b/builtin.h
index bb720004afeb632005a5622ecb9cd25f95f5caa5..03ee7bf780be93601f9190b733984ad82951952b 100644 (file)
--- a/builtin.h
+++ b/builtin.h
@@ -60,6 +60,7 @@ extern int cmd_read_tree(int argc, const char **argv, const char *prefix);
 extern int cmd_reflog(int argc, const char **argv, const char *prefix);
 extern int cmd_config(int argc, const char **argv, const char *prefix);
 extern int cmd_rerere(int argc, const char **argv, const char *prefix);
+extern int cmd_reset(int argc, const char **argv, const char *prefix);
 extern int cmd_rev_list(int argc, const char **argv, const char *prefix);
 extern int cmd_rev_parse(int argc, const char **argv, const char *prefix);
 extern int cmd_revert(int argc, const char **argv, const char *prefix);

diff --git a/contrib/examples/git-reset.sh b/contrib/examples/git-reset.sh
new file mode 100755 (executable)
index 0000000..1dc606f
--- /dev/null
+++ b/contrib/examples/git-reset.sh
@@ -0,0 +1,106 @@
+#!/bin/sh
+#
+# Copyright (c) 2005, 2006 Linus Torvalds and Junio C Hamano
+#
+USAGE='[--mixed | --soft | --hard]  [<commit-ish>] [ [--] <paths>...]'
+SUBDIRECTORY_OK=Yes
+. git-sh-setup
+set_reflog_action "reset $*"
+require_work_tree
+
+update= reset_type=--mixed
+unset rev
+
+while case $# in 0) break ;; esac
+do
+       case "$1" in
+       --mixed | --soft | --hard)
+               reset_type="$1"
+               ;;
+       --)
+               break
+               ;;
+       -*)
+               usage
+               ;;
+       *)
+               rev=$(git rev-parse --verify "$1") || exit
+               shift
+               break
+               ;;
+       esac
+       shift
+done
+
+: ${rev=HEAD}
+rev=$(git rev-parse --verify $rev^0) || exit
+
+# Skip -- in "git reset HEAD -- foo" and "git reset -- foo".
+case "$1" in --) shift ;; esac
+
+# git reset --mixed tree [--] paths... can be used to
+# load chosen paths from the tree into the index without
+# affecting the working tree nor HEAD.
+if test $# != 0
+then
+       test "$reset_type" = "--mixed" ||
+               die "Cannot do partial $reset_type reset."
+
+       git diff-index --cached $rev -- "$@" |
+       sed -e 's/^:\([0-7][0-7]*\) [0-7][0-7]* \([0-9a-f][0-9a-f]*\) [0-9a-f][0-9a-f]* [A-Z]   \(.*\)$/\1 \2   \3/' |
+       git update-index --add --remove --index-info || exit
+       git update-index --refresh
+       exit
+fi
+
+cd_to_toplevel
+
+if test "$reset_type" = "--hard"
+then
+       update=-u
+fi
+
+# Soft reset does not touch the index file nor the working tree
+# at all, but requires them in a good order.  Other resets reset
+# the index file to the tree object we are switching to.
+if test "$reset_type" = "--soft"
+then
+       if test -f "$GIT_DIR/MERGE_HEAD" ||
+          test "" != "$(git ls-files --unmerged)"
+       then
+               die "Cannot do a soft reset in the middle of a merge."
+       fi
+else
+       git read-tree -v --reset $update "$rev" || exit
+fi
+
+# Any resets update HEAD to the head being switched to.
+if orig=$(git rev-parse --verify HEAD 2>/dev/null)
+then
+       echo "$orig" >"$GIT_DIR/ORIG_HEAD"
+else
+       rm -f "$GIT_DIR/ORIG_HEAD"
+fi
+git update-ref -m "$GIT_REFLOG_ACTION" HEAD "$rev"
+update_ref_status=$?
+
+case "$reset_type" in
+--hard )
+       test $update_ref_status = 0 && {
+               printf "HEAD is now at "
+               GIT_PAGER= git log --max-count=1 --pretty=oneline \
+                       --abbrev-commit HEAD
+       }
+       ;;
+--soft )
+       ;; # Nothing else to do
+--mixed )
+       # Report what has not been updated.
+       git update-index --refresh
+       ;;
+esac
+
+rm -f "$GIT_DIR/MERGE_HEAD" "$GIT_DIR/rr-cache/MERGE_RR" \
+       "$GIT_DIR/SQUASH_MSG" "$GIT_DIR/MERGE_MSG"
+
+exit $update_ref_status

diff --git a/git-reset.sh b/git-reset.sh
deleted file mode 100755 (executable)
index 1dc606f..0000000
--- a/git-reset.sh
+++ /dev/null
@@ -1,106 +0,0 @@
-#!/bin/sh
-#
-# Copyright (c) 2005, 2006 Linus Torvalds and Junio C Hamano
-#
-USAGE='[--mixed | --soft | --hard]  [<commit-ish>] [ [--] <paths>...]'
-SUBDIRECTORY_OK=Yes
-. git-sh-setup
-set_reflog_action "reset $*"
-require_work_tree
-
-update= reset_type=--mixed
-unset rev
-
-while case $# in 0) break ;; esac
-do
-       case "$1" in
-       --mixed | --soft | --hard)
-               reset_type="$1"
-               ;;
-       --)
-               break
-               ;;
-       -*)
-               usage
-               ;;
-       *)
-               rev=$(git rev-parse --verify "$1") || exit
-               shift
-               break
-               ;;
-       esac
-       shift
-done
-
-: ${rev=HEAD}
-rev=$(git rev-parse --verify $rev^0) || exit
-
-# Skip -- in "git reset HEAD -- foo" and "git reset -- foo".
-case "$1" in --) shift ;; esac
-
-# git reset --mixed tree [--] paths... can be used to
-# load chosen paths from the tree into the index without
-# affecting the working tree nor HEAD.
-if test $# != 0
-then
-       test "$reset_type" = "--mixed" ||
-               die "Cannot do partial $reset_type reset."
-
-       git diff-index --cached $rev -- "$@" |
-       sed -e 's/^:\([0-7][0-7]*\) [0-7][0-7]* \([0-9a-f][0-9a-f]*\) [0-9a-f][0-9a-f]* [A-Z]   \(.*\)$/\1 \2   \3/' |
-       git update-index --add --remove --index-info || exit
-       git update-index --refresh
-       exit
-fi
-
-cd_to_toplevel
-
-if test "$reset_type" = "--hard"
-then
-       update=-u
-fi
-
-# Soft reset does not touch the index file nor the working tree
-# at all, but requires them in a good order.  Other resets reset
-# the index file to the tree object we are switching to.
-if test "$reset_type" = "--soft"
-then
-       if test -f "$GIT_DIR/MERGE_HEAD" ||
-          test "" != "$(git ls-files --unmerged)"
-       then
-               die "Cannot do a soft reset in the middle of a merge."
-       fi
-else
-       git read-tree -v --reset $update "$rev" || exit
-fi
-
-# Any resets update HEAD to the head being switched to.
-if orig=$(git rev-parse --verify HEAD 2>/dev/null)
-then
-       echo "$orig" >"$GIT_DIR/ORIG_HEAD"
-else
-       rm -f "$GIT_DIR/ORIG_HEAD"
-fi
-git update-ref -m "$GIT_REFLOG_ACTION" HEAD "$rev"
-update_ref_status=$?
-
-case "$reset_type" in
---hard )
-       test $update_ref_status = 0 && {
-               printf "HEAD is now at "
-               GIT_PAGER= git log --max-count=1 --pretty=oneline \
-                       --abbrev-commit HEAD
-       }
-       ;;
---soft )
-       ;; # Nothing else to do
---mixed )
-       # Report what has not been updated.
-       git update-index --refresh
-       ;;
-esac
-
-rm -f "$GIT_DIR/MERGE_HEAD" "$GIT_DIR/rr-cache/MERGE_RR" \
-       "$GIT_DIR/SQUASH_MSG" "$GIT_DIR/MERGE_MSG"
-
-exit $update_ref_status

diff --git a/git.c b/git.c
index fd3d83cd4c49409214dcc3e54480b7650e1b8b18..56ae8ccccf6917fb27f74d56d7d96a9c4788cb54 100644 (file)
--- a/git.c
+++ b/git.c
@@ -364,6 +364,7 @@ static void handle_internal_command(int argc, const char **argv)
                { "reflog", cmd_reflog, RUN_SETUP },
                { "repo-config", cmd_config },
                { "rerere", cmd_rerere, RUN_SETUP },
+               { "reset", cmd_reset, RUN_SETUP },
                { "rev-list", cmd_rev_list, RUN_SETUP },
                { "rev-parse", cmd_rev_parse, RUN_SETUP },
                { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },