sequencer: refactor sequencer_add_exec_commands() to work on a todo_list

This refactors sequencer_add_exec_commands() to work on a todo_list to
avoid redundant reads and writes to the disk.

Instead of inserting the `exec' commands between the other commands and
re-parsing the buffer at the end, they are appended to the buffer once,
and a new list of items is created.  Items from the old list are copied
across and new `exec' items are appended when necessary.  This
eliminates the need to reparse the buffer, but this also means we have
to use todo_list_write_to_disk() to write the file.

todo_list_add_exec_commands() and sequencer_add_exec_commands() are
modified to take a string list instead of a string -- one item for each
command.  This makes it easier to insert a new command to the todo list
for each command to execute.

sequencer_add_exec_commands() still reads the todo list from the disk,
as it is needed by rebase -p.

complete_action() still uses sequencer_add_exec_commands() for now.
This will be changed in a future commit.

Signed-off-by: Alban Gruin <alban.gruin@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/rebase--interactive.c b/builtin/rebase--interactive.c
index df19ccaeb9e8a927fcc8c9ff63a254f1d09be8d0..813bc34140e3c0da2839fde98d1175b24c488a35 100644 (file)
--- a/builtin/rebase--interactive.c
+++ b/builtin/rebase--interactive.c
@@ -65,7 +65,7 @@ static int do_interactive_rebase(struct replay_opts *opts, unsigned flags,
                                 const char *onto, const char *onto_name,
                                 const char *squash_onto, const char *head_name,
                                 const char *restrict_revision, char *raw_strategies,
-                                const char *cmd, unsigned autosquash)
+                                struct string_list *commands, unsigned autosquash)
 {
        int ret;
        const char *head_hash = NULL;
@@ -116,7 +116,7 @@ static int do_interactive_rebase(struct replay_opts *opts, unsigned flags,
                discard_cache();
                ret = complete_action(the_repository, opts, flags,
                                      shortrevisions, onto_name, onto,
-                                     head_hash, cmd, autosquash);
+                                     head_hash, commands, autosquash);
        }
 
        free(revisions);
@@ -139,6 +139,7 @@ int cmd_rebase__interactive(int argc, const char **argv, const char *prefix)
        const char *onto = NULL, *onto_name = NULL, *restrict_revision = NULL,
                *squash_onto = NULL, *upstream = NULL, *head_name = NULL,
                *switch_to = NULL, *cmd = NULL;
+       struct string_list commands = STRING_LIST_INIT_DUP;
        char *raw_strategies = NULL;
        enum {
                NONE = 0, CONTINUE, SKIP, EDIT_TODO, SHOW_CURRENT_PATCH,
@@ -221,6 +222,14 @@ int cmd_rebase__interactive(int argc, const char **argv, const char *prefix)
                warning(_("--[no-]rebase-cousins has no effect without "
                          "--rebase-merges"));
 
+       if (cmd && *cmd) {
+               string_list_split(&commands, cmd, '\n', -1);
+
+               /* rebase.c adds a new line to cmd after every command,
+                * so here the last command is always empty */
+               string_list_remove_empty_items(&commands, 0);
+       }
+
        switch (command) {
        case NONE:
                if (!onto && !upstream)
@@ -228,7 +237,7 @@ int cmd_rebase__interactive(int argc, const char **argv, const char *prefix)
 
                ret = do_interactive_rebase(&opts, flags, switch_to, upstream, onto,
                                            onto_name, squash_onto, head_name, restrict_revision,
-                                           raw_strategies, cmd, autosquash);
+                                           raw_strategies, &commands, autosquash);
                break;
        case SKIP: {
                struct string_list merge_rr = STRING_LIST_INIT_DUP;
@@ -262,11 +271,12 @@ int cmd_rebase__interactive(int argc, const char **argv, const char *prefix)
                ret = rearrange_squash(the_repository);
                break;
        case ADD_EXEC:
-               ret = sequencer_add_exec_commands(the_repository, cmd);
+               ret = sequencer_add_exec_commands(the_repository, &commands);
                break;
        default:
                BUG("invalid command '%d'", command);
        }
 
+       string_list_clear(&commands, 0);
        return !!ret;
 }

diff --git a/sequencer.c b/sequencer.c
index 99e12c751ed48e6e7d30f18255e25ca40f01297f..4c076bd18359298185a4f486b20eefbcb9adee53 100644 (file)
--- a/sequencer.c
+++ b/sequencer.c
@@ -4505,61 +4505,95 @@ int sequencer_make_script(struct repository *r, FILE *out,
  * Add commands after pick and (series of) squash/fixup commands
  * in the todo list.
  */
-int sequencer_add_exec_commands(struct repository *r,
-                               const char *commands)
+static void todo_list_add_exec_commands(struct todo_list *todo_list,
+                                       struct string_list *commands)
 {
-       const char *todo_file = rebase_path_todo();
-       struct todo_list todo_list = TODO_LIST_INIT;
-       struct strbuf *buf = &todo_list.buf;
-       size_t offset = 0, commands_len = strlen(commands);
-       int i, insert;
+       struct strbuf *buf = &todo_list->buf;
+       size_t base_offset = buf->len;
+       int i, insert, nr = 0, alloc = 0;
+       struct todo_item *items = NULL, *base_items = NULL;
 
-       if (strbuf_read_file(&todo_list.buf, todo_file, 0) < 0)
-               return error(_("could not read '%s'."), todo_file);
+       base_items = xcalloc(commands->nr, sizeof(struct todo_item));
+       for (i = 0; i < commands->nr; i++) {
+               size_t command_len = strlen(commands->items[i].string);
 
-       if (todo_list_parse_insn_buffer(r, todo_list.buf.buf, &todo_list)) {
-               todo_list_release(&todo_list);
-               return error(_("unusable todo list: '%s'"), todo_file);
+               strbuf_addstr(buf, commands->items[i].string);
+               strbuf_addch(buf, '\n');
+
+               base_items[i].command = TODO_EXEC;
+               base_items[i].offset_in_buf = base_offset;
+               base_items[i].arg_offset = base_offset + strlen("exec ");
+               base_items[i].arg_len = command_len - strlen("exec ");
+
+               base_offset += command_len + 1;
        }
 
        /*
         * Insert <commands> after every pick. Here, fixup/squash chains
         * are considered part of the pick, so we insert the commands *after*
         * those chains if there are any.
+        *
+        * As we insert the exec commands immediatly after rearranging
+        * any fixups and before the user edits the list, a fixup chain
+        * can never contain comments (any comments are empty picks that
+        * have been commented out because the user did not specify
+        * --keep-empty).  So, it is safe to insert an exec command
+        * without looking at the command following a comment.
         */
-       insert = -1;
-       for (i = 0; i < todo_list.nr; i++) {
-               enum todo_command command = todo_list.items[i].command;
-
-               if (insert >= 0) {
-                       /* skip fixup/squash chains */
-                       if (command == TODO_COMMENT)
-                               continue;
-                       else if (is_fixup(command)) {
-                               insert = i + 1;
-                               continue;
-                       }
-                       strbuf_insert(buf,
-                                     todo_list.items[insert].offset_in_buf +
-                                     offset, commands, commands_len);
-                       offset += commands_len;
-                       insert = -1;
+       insert = 0;
+       for (i = 0; i < todo_list->nr; i++) {
+               enum todo_command command = todo_list->items[i].command;
+               if (insert && !is_fixup(command)) {
+                       ALLOC_GROW(items, nr + commands->nr, alloc);
+                       COPY_ARRAY(items + nr, base_items, commands->nr);
+                       nr += commands->nr;
+
+                       insert = 0;
                }
 
+               ALLOC_GROW(items, nr + 1, alloc);
+               items[nr++] = todo_list->items[i];
+
                if (command == TODO_PICK || command == TODO_MERGE)
-                       insert = i + 1;
+                       insert = 1;
        }
 
        /* insert or append final <commands> */
-       if (insert >= 0 && insert < todo_list.nr)
-               strbuf_insert(buf, todo_list.items[insert].offset_in_buf +
-                             offset, commands, commands_len);
-       else if (insert >= 0 || !offset)
-               strbuf_add(buf, commands, commands_len);
+       if (insert || nr == todo_list->nr) {
+               ALLOC_GROW(items, nr + commands->nr, alloc);
+               COPY_ARRAY(items + nr, base_items, commands->nr);
+               nr += commands->nr;
+       }
+
+       free(base_items);
+       FREE_AND_NULL(todo_list->items);
+       todo_list->items = items;
+       todo_list->nr = nr;
+       todo_list->alloc = alloc;
+}
+
+int sequencer_add_exec_commands(struct repository *r,
+                               struct string_list *commands)
+{
+       const char *todo_file = rebase_path_todo();
+       struct todo_list todo_list = TODO_LIST_INIT;
+       int res;
+
+       if (strbuf_read_file(&todo_list.buf, todo_file, 0) < 0)
+               return error_errno(_("could not read '%s'."), todo_file);
 
-       i = write_message(buf->buf, buf->len, todo_file, 0);
+       if (todo_list_parse_insn_buffer(r, todo_list.buf.buf, &todo_list)) {
+               todo_list_release(&todo_list);
+               return error(_("unusable todo list: '%s'"), todo_file);
+       }
+
+       todo_list_add_exec_commands(&todo_list, commands);
+       res = todo_list_write_to_file(r, &todo_list, todo_file, NULL, NULL, -1, 0);
        todo_list_release(&todo_list);
-       return i;
+
+       if (res)
+               return error_errno(_("could not write '%s'."), todo_file);
+       return 0;
 }
 
 static void todo_list_to_strbuf(struct repository *r, struct todo_list *todo_list,
@@ -4790,7 +4824,7 @@ static int skip_unnecessary_picks(struct repository *r, struct object_id *output
 
 int complete_action(struct repository *r, struct replay_opts *opts, unsigned flags,
                    const char *shortrevisions, const char *onto_name,
-                   const char *onto, const char *orig_head, const char *cmd,
+                   const char *onto, const char *orig_head, struct string_list *commands,
                    unsigned autosquash)
 {
        const char *shortonto, *todo_file = rebase_path_todo();
@@ -4809,8 +4843,8 @@ int complete_action(struct repository *r, struct replay_opts *opts, unsigned fla
        if (autosquash && rearrange_squash(r))
                return -1;
 
-       if (cmd && *cmd)
-               sequencer_add_exec_commands(r, cmd);
+       if (commands->nr)
+               sequencer_add_exec_commands(r, commands);
 
        if (strbuf_read_file(buf, todo_file, 0) < 0)
                return error_errno(_("could not read '%s'."), todo_file);

diff --git a/sequencer.h b/sequencer.h
index 217353e9f0b1996e537799cbe7a1f0d2567aeb4f..87d04a3b9bda8144a48adcf1c30cc6c96dcf4e6a 100644 (file)
--- a/sequencer.h
+++ b/sequencer.h
@@ -146,12 +146,13 @@ int sequencer_make_script(struct repository *r, FILE *out, int argc,
                          const char **argv,
                          unsigned flags);
 
-int sequencer_add_exec_commands(struct repository *r, const char *command);
+int sequencer_add_exec_commands(struct repository *r,
+                               struct string_list *commands);
 int transform_todo_file(struct repository *r, unsigned flags);
 int check_todo_list_from_file(struct repository *r);
 int complete_action(struct repository *r, struct replay_opts *opts, unsigned flags,
                    const char *shortrevisions, const char *onto_name,
-                   const char *onto, const char *orig_head, const char *cmd,
+                   const char *onto, const char *orig_head, struct string_list *commands,
                    unsigned autosquash);
 int rearrange_squash(struct repository *r);