Re: [PATCH 03/10] unpack-trees.[ch]: embed "dir" in "struct unpack_trees_options"

Change the "struct dir" in "struct unpack_trees_options" away from a
pointer to being embedded in the struct itself, this mean that we can
initialize it with our new UNPACK_TREES_OPTIONS_INIT macro.

As it turned out nothing actually needed to provide its own "struct
dir" to this API, there's another patch to "hide" the struct instead,
see the discussion at [1], but I think just allocating it on the stack
along with the rest makes more sense.

This fixes a memory leak in "builtin/checkout.c" that's been there
since the clear_unpack_trees_porcelain() function was added in
1c41d2805e4 (unpack_trees_options: free messages when done,
2018-05-21), i.e. we still had a memory leak from allocating the "dir"
member here. That "dir" member had in turn been with us ever since
782c2d65c24 (Build in checkout, 2008-02-07).

This fixes that memory leak, and allows us to remove the boilerplate
dir_clear() elsewhere in favor of just using
clear_unpack_trees_porcelain().

1. https://lore.kernel.org/git/87ilyjviiy.fsf@evledraar.gmail.com/ (local)

Signed-off-by: Ævar Arnfjörð Bjarmason <redacted>
---
 builtin/checkout.c  |  5 ++---
 builtin/read-tree.c | 11 ++++-------
 merge-ort.c         |  7 ++-----
 merge.c             |  7 ++-----
 unpack-trees.c      | 10 ++++------
 unpack-trees.h      |  4 +++-
 6 files changed, 17 insertions(+), 27 deletions(-)

diff --git a/builtin/checkout.c b/builtin/checkout.c
index fea4533dbec..d4b88affba7 100644
--- a/builtin/checkout.c
+++ b/builtin/checkout.c

@@ -745,9 +745,8 @@ static int merge_working_tree(const struct checkout_opts *opts,
                                       &new_branch_info->commit->object.oid :
                                       &new_branch_info->oid, NULL);
                if (opts->overwrite_ignore) {
-                       topts.dir = xcalloc(1, sizeof(*topts.dir));
-                       topts.dir->flags |= DIR_SHOW_IGNORED;
-                       setup_standard_excludes(topts.dir);
+                       topts.dir.flags |= DIR_SHOW_IGNORED;
+                       setup_standard_excludes(&topts.dir);
                }
                tree = parse_tree_indirect(old_branch_info->commit ?
                                           &old_branch_info->commit->object.oid :

diff --git a/builtin/read-tree.c b/builtin/read-tree.c
index 847182fdad6..06f3b97ac05 100644
--- a/builtin/read-tree.c
+++ b/builtin/read-tree.c

@@ -53,20 +53,17 @@ static int index_output_cb(const struct option *opt, const char *arg,
 static int exclude_per_directory_cb(const struct option *opt, const char *arg,
                                    int unset)
 {
-       struct dir_struct *dir;
        struct unpack_trees_options *opts;

        BUG_ON_OPT_NEG(unset);

        opts = (struct unpack_trees_options *)opt->value;

-       if (opts->dir)
+       if (opts->dir.exclude_per_dir)
                die("more than one --exclude-per-directory given.");

-       dir = xcalloc(1, sizeof(*opts->dir));
-       dir->flags |= DIR_SHOW_IGNORED;
-       dir->exclude_per_dir = arg;
-       opts->dir = dir;
+       opts->dir.flags |= DIR_SHOW_IGNORED;
+       opts->dir.exclude_per_dir = arg;
        /* We do not need to nor want to do read-directory
         * here; we are merely interested in reusing the
         * per directory ignore stack mechanism.

@@ -208,7 +205,7 @@ int cmd_read_tree(int argc, const char **argv, const char *cmd_prefix)
        if ((opts.update || opts.index_only) && !opts.merge)
                die("%s is meaningless without -m, --reset, or --prefix",
                    opts.update ? "-u" : "-i");
-       if ((opts.dir && !opts.update))
+       if ((opts.dir.exclude_per_dir && !opts.update))
                die("--exclude-per-directory is meaningless unless -u");
        if (opts.merge && !opts.index_only)
                setup_work_tree();

diff --git a/merge-ort.c b/merge-ort.c
index 75d2b8e4b99..e526b78b88d 100644
--- a/merge-ort.c
+++ b/merge-ort.c

@@ -4045,9 +4045,8 @@ static int checkout(struct merge_options *opt,
        unpack_opts.verbose_update = (opt->verbosity > 2);
        unpack_opts.fn = twoway_merge;
        if (1/* FIXME: opts->overwrite_ignore*/) {
-               CALLOC_ARRAY(unpack_opts.dir, 1);
-               unpack_opts.dir->flags |= DIR_SHOW_IGNORED;
-               setup_standard_excludes(unpack_opts.dir);
+               unpack_opts.dir.flags |= DIR_SHOW_IGNORED;
+               setup_standard_excludes(&unpack_opts.dir);
        }
        parse_tree(prev);
        init_tree_desc(&trees[0], prev->buffer, prev->size);

@@ -4056,8 +4055,6 @@ static int checkout(struct merge_options *opt,

        ret = unpack_trees(2, trees, &unpack_opts);
        clear_unpack_trees_porcelain(&unpack_opts);
-       dir_clear(unpack_opts.dir);
-       FREE_AND_NULL(unpack_opts.dir);
        return ret;
 }

diff --git a/merge.c b/merge.c
index 086f04b0f97..9cb32990dd9 100644
--- a/merge.c
+++ b/merge.c

@@ -53,7 +53,6 @@ int checkout_fast_forward(struct repository *r,
        struct unpack_trees_options opts = UNPACK_TREES_OPTIONS_INIT;
        struct tree_desc t[MAX_UNPACK_TREES];
        int i, nr_trees = 0;
-       struct dir_struct dir = DIR_INIT;
        struct lock_file lock_file = LOCK_INIT;

        refresh_index(r->index, REFRESH_QUIET, NULL, NULL, NULL);

@@ -80,9 +79,8 @@ int checkout_fast_forward(struct repository *r,
        }

        if (overwrite_ignore) {
-               dir.flags |= DIR_SHOW_IGNORED;
-               setup_standard_excludes(&dir);
-               opts.dir = &dir;
+               opts.dir.flags |= DIR_SHOW_IGNORED;
+               setup_standard_excludes(&opts.dir);
        }

        opts.head_idx = 1;

@@ -100,7 +98,6 @@ int checkout_fast_forward(struct repository *r,
                clear_unpack_trees_porcelain(&opts);
                return -1;
        }
-       dir_clear(&dir);
        clear_unpack_trees_porcelain(&opts);

        if (write_locked_index(r->index, &lock_file, COMMIT_LOCK))

diff --git a/unpack-trees.c b/unpack-trees.c
index 393c1f35a5d..94767d3f96f 100644
--- a/unpack-trees.c
+++ b/unpack-trees.c

@@ -196,6 +196,7 @@ void unpack_trees_options_init(struct unpack_trees_options *o)
 void clear_unpack_trees_porcelain(struct unpack_trees_options *opts)
 {
        strvec_clear(&opts->msgs_to_free);
+       dir_clear(&opts->dir);
        memset(opts->msgs, 0, sizeof(opts->msgs));
 }

@@ -2085,7 +2086,7 @@ static int verify_clean_subdirectory(const struct cache_entry *ce,
         */
        int namelen;
        int i;
-       struct dir_struct d;
+       struct dir_struct d = DIR_INIT;
        char *pathbuf;
        int cnt = 0;

@@ -2136,9 +2137,7 @@ static int verify_clean_subdirectory(const struct cache_entry *ce,
         */
        pathbuf = xstrfmt("%.*s/", namelen, ce->name);

-       memset(&d, 0, sizeof(d));
-       if (o->dir)
-               d.exclude_per_dir = o->dir->exclude_per_dir;
+       d.exclude_per_dir = o->dir.exclude_per_dir;
        i = read_directory(&d, o->src_index, pathbuf, namelen+1, NULL);
        if (i)
                return add_rejected_path(o, ERROR_NOT_UPTODATE_DIR, ce->name);

@@ -2179,8 +2178,7 @@ static int check_ok_to_remove(const char *name, int len, int dtype,
        if (ignore_case && icase_exists(o, name, len, st))
                return 0;

-       if (o->dir &&
-           is_excluded(o->dir, o->src_index, name, &dtype))
+       if (is_excluded(&o->dir, o->src_index, name, &dtype))
                /*
                 * ce->name is explicitly excluded, so it is Ok to
                 * overwrite it.

diff --git a/unpack-trees.h b/unpack-trees.h
index 892b65ea623..40c4841748d 100644
--- a/unpack-trees.h
+++ b/unpack-trees.h

@@ -5,6 +5,7 @@
 #include "strvec.h"
 #include "string-list.h"
 #include "tree-walk.h"
+#include "dir.h"

 #define MAX_UNPACK_TREES MAX_TRAVERSE_TREES

@@ -66,7 +67,7 @@ struct unpack_trees_options {
                     dry_run;
        const char *prefix;
        int cache_bottom;
-       struct dir_struct *dir;
+       struct dir_struct dir;
        struct pathspec *pathspec;
        merge_fn_t fn;
        const char *msgs[NB_UNPACK_TREES_WARNING_TYPES];

@@ -93,6 +94,7 @@ struct unpack_trees_options {

 #define UNPACK_TREES_OPTIONS_INIT { \
        .msgs_to_free = STRVEC_INIT, \
+       .dir = DIR_INIT, \
 }
 void unpack_trees_options_init(struct unpack_trees_options *o);

--

2.33.0.1404.g83021034c5d