midx: factor out `fill_pack_info()`

When selecting which packfiles will be written while generating a MIDX,
the MIDX internals fill out a 'struct pack_info' with various pieces of
book-keeping.

Instead of filling out each field of the `pack_info` structure
individually in each of the two spots that modify the array of such
structures (`ctx->info`), extract a common routine that does this for
us.

This reduces the code duplication by a modest amount. But more
importantly, it zero-initializes the structure before assigning values
into it. This hardens us for a future change which will add additional
fields to this structure which (until this patch) was not
zero-initialized.

As a result, any new fields added to the `pack_info` structure need only
be updated in a single location, instead of at each spot within midx.c.

There are no functional changes in this patch.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/midx.c b/midx.c
index 778dd536c8d087e5f62c8433690bf9dfe2dd014c..8dba67ddbec2167b39e3e6f88f507c0440bbe045 100644 (file)
--- a/midx.c
+++ b/midx.c
@@ -475,6 +475,17 @@ struct pack_info {
        unsigned expired : 1;
 };
 
+static void fill_pack_info(struct pack_info *info,
+                          struct packed_git *p, const char *pack_name,
+                          uint32_t orig_pack_int_id)
+{
+       memset(info, 0, sizeof(struct pack_info));
+
+       info->orig_pack_int_id = orig_pack_int_id;
+       info->pack_name = xstrdup(pack_name);
+       info->p = p;
+}
+
 static int pack_info_compare(const void *_a, const void *_b)
 {
        struct pack_info *a = (struct pack_info *)_a;
@@ -515,6 +526,7 @@ static void add_pack_to_midx(const char *full_path, size_t full_path_len,
                             const char *file_name, void *data)
 {
        struct write_midx_context *ctx = data;
+       struct packed_git *p;
 
        if (ends_with(file_name, ".idx")) {
                display_progress(ctx->progress, ++ctx->pack_paths_checked);
@@ -541,27 +553,22 @@ static void add_pack_to_midx(const char *full_path, size_t full_path_len,
 
                ALLOC_GROW(ctx->info, ctx->nr + 1, ctx->alloc);
 
-               ctx->info[ctx->nr].p = add_packed_git(full_path,
-                                                     full_path_len,
-                                                     0);
-
-               if (!ctx->info[ctx->nr].p) {
+               p = add_packed_git(full_path, full_path_len, 0);
+               if (!p) {
                        warning(_("failed to add packfile '%s'"),
                                full_path);
                        return;
                }
 
-               if (open_pack_index(ctx->info[ctx->nr].p)) {
+               if (open_pack_index(p)) {
                        warning(_("failed to open pack-index '%s'"),
                                full_path);
-                       close_pack(ctx->info[ctx->nr].p);
-                       FREE_AND_NULL(ctx->info[ctx->nr].p);
+                       close_pack(p);
+                       free(p);
                        return;
                }
 
-               ctx->info[ctx->nr].pack_name = xstrdup(file_name);
-               ctx->info[ctx->nr].orig_pack_int_id = ctx->nr;
-               ctx->info[ctx->nr].expired = 0;
+               fill_pack_info(&ctx->info[ctx->nr], p, file_name, ctx->nr);
                ctx->nr++;
        }
 }
@@ -1321,11 +1328,6 @@ static int write_midx_internal(const char *object_dir,
                for (i = 0; i < ctx.m->num_packs; i++) {
                        ALLOC_GROW(ctx.info, ctx.nr + 1, ctx.alloc);
 
-                       ctx.info[ctx.nr].orig_pack_int_id = i;
-                       ctx.info[ctx.nr].pack_name = xstrdup(ctx.m->pack_names[i]);
-                       ctx.info[ctx.nr].p = ctx.m->packs[i];
-                       ctx.info[ctx.nr].expired = 0;
-
                        if (flags & MIDX_WRITE_REV_INDEX) {
                                /*
                                 * If generating a reverse index, need to have
@@ -1341,10 +1343,10 @@ static int write_midx_internal(const char *object_dir,
                                if (open_pack_index(ctx.m->packs[i]))
                                        die(_("could not open index for %s"),
                                            ctx.m->packs[i]->pack_name);
-                               ctx.info[ctx.nr].p = ctx.m->packs[i];
                        }
 
-                       ctx.nr++;
+                       fill_pack_info(&ctx.info[ctx.nr++], ctx.m->packs[i],
+                                      ctx.m->pack_names[i], i);
                }
        }