Merge branch 'sb/sequencer-abort-safety'
[gitweb.git] / sequencer.c
index 30b10ba143959bf2618872427f730a9f0e30d369..9adb7bbf1d4815d9e4f67b66e90c9ec327b2fb72 100644 (file)
@@ -16,6 +16,7 @@
 #include "refs.h"
 #include "argv-array.h"
 #include "quote.h"
+#include "trailer.h"
 
 #define GIT_REFLOG_ACTION "GIT_REFLOG_ACTION"
 
@@ -27,6 +28,7 @@ GIT_PATH_FUNC(git_path_seq_dir, "sequencer")
 static GIT_PATH_FUNC(git_path_todo_file, "sequencer/todo")
 static GIT_PATH_FUNC(git_path_opts_file, "sequencer/opts")
 static GIT_PATH_FUNC(git_path_head_file, "sequencer/head")
+static GIT_PATH_FUNC(git_path_abort_safety_file, "sequencer/abort-safety")
 
 /*
  * A script to set the GIT_AUTHOR_NAME, GIT_AUTHOR_EMAIL, and
@@ -56,30 +58,6 @@ static const char *get_todo_path(const struct replay_opts *opts)
        return git_path_todo_file();
 }
 
-static int is_rfc2822_line(const char *buf, int len)
-{
-       int i;
-
-       for (i = 0; i < len; i++) {
-               int ch = buf[i];
-               if (ch == ':')
-                       return 1;
-               if (!isalnum(ch) && ch != '-')
-                       break;
-       }
-
-       return 0;
-}
-
-static int is_cherry_picked_from_line(const char *buf, int len)
-{
-       /*
-        * We only care that it looks roughly like (cherry picked from ...)
-        */
-       return len > strlen(cherry_picked_prefix) + 1 &&
-               starts_with(buf, cherry_picked_prefix) && buf[len - 1] == ')';
-}
-
 /*
  * Returns 0 for non-conforming footer
  * Returns 1 for conforming footer
@@ -89,49 +67,25 @@ static int is_cherry_picked_from_line(const char *buf, int len)
 static int has_conforming_footer(struct strbuf *sb, struct strbuf *sob,
        int ignore_footer)
 {
-       char prev;
-       int i, k;
-       int len = sb->len - ignore_footer;
-       const char *buf = sb->buf;
-       int found_sob = 0;
-
-       /* footer must end with newline */
-       if (!len || buf[len - 1] != '\n')
-               return 0;
+       struct trailer_info info;
+       int i;
+       int found_sob = 0, found_sob_last = 0;
 
-       prev = '\0';
-       for (i = len - 1; i > 0; i--) {
-               char ch = buf[i];
-               if (prev == '\n' && ch == '\n') /* paragraph break */
-                       break;
-               prev = ch;
-       }
+       trailer_info_get(&info, sb->buf);
 
-       /* require at least one blank line */
-       if (prev != '\n' || buf[i] != '\n')
+       if (info.trailer_start == info.trailer_end)
                return 0;
 
-       /* advance to start of last paragraph */
-       while (i < len - 1 && buf[i] == '\n')
-               i++;
-
-       for (; i < len; i = k) {
-               int found_rfc2822;
-
-               for (k = i; k < len && buf[k] != '\n'; k++)
-                       ; /* do nothing */
-               k++;
+       for (i = 0; i < info.trailer_nr; i++)
+               if (sob && !strncmp(info.trailers[i], sob->buf, sob->len)) {
+                       found_sob = 1;
+                       if (i == info.trailer_nr - 1)
+                               found_sob_last = 1;
+               }
 
-               found_rfc2822 = is_rfc2822_line(buf + i, k - i - 1);
-               if (found_rfc2822 && sob &&
-                   !strncmp(buf + i, sob->buf, sob->len))
-                       found_sob = k;
+       trailer_info_release(&info);
 
-               if (!(found_rfc2822 ||
-                     is_cherry_picked_from_line(buf + i, k - i - 1)))
-                       return 0;
-       }
-       if (found_sob == i)
+       if (found_sob_last)
                return 3;
        if (found_sob)
                return 2;
@@ -310,6 +264,20 @@ static int error_dirty_index(struct replay_opts *opts)
        return -1;
 }
 
+static void update_abort_safety_file(void)
+{
+       struct object_id head;
+
+       /* Do nothing on a single-pick */
+       if (!file_exists(git_path_seq_dir()))
+               return;
+
+       if (!get_oid("HEAD", &head))
+               write_file(git_path_abort_safety_file(), "%s", oid_to_hex(&head));
+       else
+               write_file(git_path_abort_safety_file(), "%s", "");
+}
+
 static int fast_forward_to(const unsigned char *to, const unsigned char *from,
                        int unborn, struct replay_opts *opts)
 {
@@ -339,6 +307,7 @@ static int fast_forward_to(const unsigned char *to, const unsigned char *from,
        strbuf_release(&sb);
        strbuf_release(&err);
        ref_transaction_free(transaction);
+       update_abort_safety_file();
        return 0;
 }
 
@@ -370,7 +339,7 @@ static int do_recursive_merge(struct commit *base, struct commit *next,
        char **xopt;
        static struct lock_file index_lock;
 
-       hold_locked_index(&index_lock, 1);
+       hold_locked_index(&index_lock, LOCK_DIE_ON_ERROR);
 
        read_cache();
 
@@ -813,6 +782,7 @@ static int do_pick_commit(enum todo_command command, struct commit *commit,
 
 leave:
        free_message(commit, &msg);
+       update_abort_safety_file();
 
        return res;
 }
@@ -1132,9 +1102,34 @@ static int save_head(const char *head)
        return 0;
 }
 
+static int rollback_is_safe(void)
+{
+       struct strbuf sb = STRBUF_INIT;
+       struct object_id expected_head, actual_head;
+
+       if (strbuf_read_file(&sb, git_path_abort_safety_file(), 0) >= 0) {
+               strbuf_trim(&sb);
+               if (get_oid_hex(sb.buf, &expected_head)) {
+                       strbuf_release(&sb);
+                       die(_("could not parse %s"), git_path_abort_safety_file());
+               }
+               strbuf_release(&sb);
+       }
+       else if (errno == ENOENT)
+               oidclr(&expected_head);
+       else
+               die_errno(_("could not read '%s'"), git_path_abort_safety_file());
+
+       if (get_oid("HEAD", &actual_head))
+               oidclr(&actual_head);
+
+       return !oidcmp(&actual_head, &expected_head);
+}
+
 static int reset_for_rollback(const unsigned char *sha1)
 {
        const char *argv[4];    /* reset --merge <arg> + NULL */
+
        argv[0] = "reset";
        argv[1] = "--merge";
        argv[2] = sha1_to_hex(sha1);
@@ -1189,6 +1184,12 @@ int sequencer_rollback(struct replay_opts *opts)
                error(_("cannot abort from a branch yet to be born"));
                goto fail;
        }
+
+       if (!rollback_is_safe()) {
+               /* Do not error, just do not rollback */
+               warning(_("You seem to have moved HEAD. "
+                         "Not rewinding, check your HEAD!"));
+       } else
        if (reset_for_rollback(sha1))
                goto fail;
        strbuf_release(&buf);
@@ -1393,6 +1394,7 @@ int sequencer_pick_revisions(struct replay_opts *opts)
                return -1;
        if (save_opts(opts))
                return -1;
+       update_abort_safety_file();
        res = pick_commits(&todo_list, opts);
        todo_list_release(&todo_list);
        return res;