hashmap: improve struct hashmap member documentation

diff --git a/commit.c b/commit.c
index 11a05c1f24f541fa3495adc502cb292c3891fab4..4ff8077dbfbc6cdd6c14728a3d33a78d075c236f 100644 (file)
--- a/commit.c
+++ b/commit.c
@@ -245,16 +245,73 @@ int unregister_shallow(const unsigned char *sha1)
        return 0;
 }
 
+struct commit_buffer {
+       void *buffer;
+       unsigned long size;
+};
+define_commit_slab(buffer_slab, struct commit_buffer);
+static struct buffer_slab buffer_slab = COMMIT_SLAB_INIT(1, buffer_slab);
+
+void set_commit_buffer(struct commit *commit, void *buffer, unsigned long size)
+{
+       struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
+       v->buffer = buffer;
+       v->size = size;
+}
+
+const void *get_cached_commit_buffer(const struct commit *commit, unsigned long *sizep)
+{
+       struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
+       if (sizep)
+               *sizep = v->size;
+       return v->buffer;
+}
+
+const void *get_commit_buffer(const struct commit *commit, unsigned long *sizep)
+{
+       const void *ret = get_cached_commit_buffer(commit, sizep);
+       if (!ret) {
+               enum object_type type;
+               unsigned long size;
+               ret = read_sha1_file(commit->object.sha1, &type, &size);
+               if (!ret)
+                       die("cannot read commit object %s",
+                           sha1_to_hex(commit->object.sha1));
+               if (type != OBJ_COMMIT)
+                       die("expected commit for %s, got %s",
+                           sha1_to_hex(commit->object.sha1), typename(type));
+               if (sizep)
+                       *sizep = size;
+       }
+       return ret;
+}
+
+void unuse_commit_buffer(const struct commit *commit, const void *buffer)
+{
+       struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
+       if (v->buffer != buffer)
+               free((void *)buffer);
+}
+
 void free_commit_buffer(struct commit *commit)
 {
-       free(commit->buffer);
-       commit->buffer = NULL;
+       struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
+       free(v->buffer);
+       v->buffer = NULL;
+       v->size = 0;
 }
 
-const void *detach_commit_buffer(struct commit *commit)
+const void *detach_commit_buffer(struct commit *commit, unsigned long *sizep)
 {
-       void *ret = commit->buffer;
-       commit->buffer = NULL;
+       struct commit_buffer *v = buffer_slab_at(&buffer_slab, commit);
+       void *ret;
+
+       ret = v->buffer;
+       if (sizep)
+               *sizep = v->size;
+
+       v->buffer = NULL;
+       v->size = 0;
        return ret;
 }
 
@@ -335,7 +392,7 @@ int parse_commit(struct commit *item)
        }
        ret = parse_commit_buffer(item, buffer, size);
        if (save_commit_buffer && !ret) {
-               item->buffer = buffer;
+               set_commit_buffer(item, buffer, size);
                return 0;
        }
        free(buffer);
@@ -550,22 +607,12 @@ static void record_author_date(struct author_date_slab *author_date,
                               struct commit *commit)
 {
        const char *buf, *line_end, *ident_line;
-       char *buffer = NULL;
+       const char *buffer = get_commit_buffer(commit, NULL);
        struct ident_split ident;
        char *date_end;
        unsigned long date;
 
-       if (!commit->buffer) {
-               unsigned long size;
-               enum object_type type;
-               buffer = read_sha1_file(commit->object.sha1, &type, &size);
-               if (!buffer)
-                       return;
-       }
-
-       for (buf = commit->buffer ? commit->buffer : buffer;
-            buf;
-            buf = line_end + 1) {
+       for (buf = buffer; buf; buf = line_end + 1) {
                line_end = strchrnul(buf, '\n');
                ident_line = skip_prefix(buf, "author ");
                if (!ident_line) {
@@ -586,7 +633,7 @@ static void record_author_date(struct author_date_slab *author_date,
        *(author_date_slab_at(author_date, commit)) = date;
 
 fail_exit:
-       free(buffer);
+       unuse_commit_buffer(commit, buffer);
 }
 
 static int compare_commits_by_author_date(const void *a_, const void *b_,
@@ -1042,7 +1089,7 @@ struct commit_list *reduce_heads(struct commit_list *heads)
                p->item->object.flags |= STALE;
                num_head++;
        }
-       array = xcalloc(sizeof(*array), num_head);
+       array = xcalloc(num_head, sizeof(*array));
        for (p = heads, i = 0; p; p = p->next) {
                if (p->item->object.flags & STALE) {
                        array[i++] = p->item;
@@ -1091,17 +1138,14 @@ static int do_sign_commit(struct strbuf *buf, const char *keyid)
        return 0;
 }
 
-int parse_signed_commit(const unsigned char *sha1,
+int parse_signed_commit(const struct commit *commit,
                        struct strbuf *payload, struct strbuf *signature)
 {
+
        unsigned long size;
-       enum object_type type;
-       char *buffer = read_sha1_file(sha1, &type, &size);
+       const char *buffer = get_commit_buffer(commit, &size);
        int in_signature, saw_signature = -1;
-       char *line, *tail;
-
-       if (!buffer || type != OBJ_COMMIT)
-               goto cleanup;
+       const char *line, *tail;
 
        line = buffer;
        tail = buffer + size;
@@ -1109,7 +1153,7 @@ int parse_signed_commit(const unsigned char *sha1,
        saw_signature = 0;
        while (line < tail) {
                const char *sig = NULL;
-               char *next = memchr(line, '\n', tail - line);
+               const char *next = memchr(line, '\n', tail - line);
 
                next = next ? next + 1 : tail;
                if (in_signature && line[0] == ' ')
@@ -1130,8 +1174,7 @@ int parse_signed_commit(const unsigned char *sha1,
                }
                line = next;
        }
- cleanup:
-       free(buffer);
+       unuse_commit_buffer(commit, buffer);
        return saw_signature;
 }
 
@@ -1222,8 +1265,7 @@ void check_commit_signature(const struct commit* commit, struct signature_check
 
        sigc->result = 'N';
 
-       if (parse_signed_commit(commit->object.sha1,
-                               &payload, &signature) <= 0)
+       if (parse_signed_commit(commit, &payload, &signature) <= 0)
                goto out;
        status = verify_signed_buffer(payload.buf, payload.len,
                                      signature.buf, signature.len,
@@ -1268,11 +1310,9 @@ struct commit_extra_header *read_commit_extra_headers(struct commit *commit,
 {
        struct commit_extra_header *extra = NULL;
        unsigned long size;
-       enum object_type type;
-       char *buffer = read_sha1_file(commit->object.sha1, &type, &size);
-       if (buffer && type == OBJ_COMMIT)
-               extra = read_commit_extra_header_lines(buffer, size, exclude);
-       free(buffer);
+       const char *buffer = get_commit_buffer(commit, &size);
+       extra = read_commit_extra_header_lines(buffer, size, exclude);
+       unuse_commit_buffer(commit, buffer);
        return extra;
 }