get_expanded_map(): avoid memory leak

diff --git a/sha1_name.c b/sha1_name.c
index ad79d7b81249b6908bb9728b88addbb2fe6955cd..0e5fe7f9371d2e6ae5aa9ce99c4b6c2dfb7a456f 100644 (file)
--- a/sha1_name.c
+++ b/sha1_name.c
@@ -677,11 +677,13 @@ static int peel_onion(const char *name, int len, unsigned char *sha1)
                return -1;
 
        sp++; /* beginning of type name, or closing brace for empty */
-       if (!strncmp(commit_type, sp, 6) && sp[6] == '}')
+       if (!prefixcmp(sp, "commit}"))
                expected_type = OBJ_COMMIT;
-       else if (!strncmp(tree_type, sp, 4) && sp[4] == '}')
+       else if (!prefixcmp(sp, "tag}"))
+               expected_type = OBJ_TAG;
+       else if (!prefixcmp(sp, "tree}"))
                expected_type = OBJ_TREE;
-       else if (!strncmp(blob_type, sp, 4) && sp[4] == '}')
+       else if (!prefixcmp(sp, "blob}"))
                expected_type = OBJ_BLOB;
        else if (!prefixcmp(sp, "object}"))
                expected_type = OBJ_ANY;
@@ -1004,6 +1006,28 @@ int get_sha1_mb(const char *name, unsigned char *sha1)
        return st;
 }
 
+/* parse @something syntax, when 'something' is not {.*} */
+static int interpret_empty_at(const char *name, int namelen, int len, struct strbuf *buf)
+{
+       const char *next;
+
+       if (len || name[1] == '{')
+               return -1;
+
+       /* make sure it's a single @, or @@{.*}, not @foo */
+       next = strchr(name + len + 1, '@');
+       if (next && next[1] != '{')
+               return -1;
+       if (!next)
+               next = name + namelen;
+       if (next != name + 1)
+               return -1;
+
+       strbuf_reset(buf);
+       strbuf_add(buf, "HEAD", 4);
+       return 1;
+}
+
 static int reinterpret(const char *name, int namelen, int len, struct strbuf *buf)
 {
        /* we have extra data, which might need further processing */
@@ -1012,7 +1036,7 @@ static int reinterpret(const char *name, int namelen, int len, struct strbuf *bu
        int ret;
 
        strbuf_add(buf, name + len, namelen - len);
-       ret = interpret_branch_name(buf->buf, &tmp);
+       ret = interpret_branch_name(buf->buf, buf->len, &tmp);
        /* that data was not interpreted, remove our cruft */
        if (ret < 0) {
                strbuf_setlen(buf, used);
@@ -1046,14 +1070,16 @@ static int reinterpret(const char *name, int namelen, int len, struct strbuf *bu
  * If the input was ok but there are not N branch switches in the
  * reflog, it returns 0.
  */
-int interpret_branch_name(const char *name, struct strbuf *buf)
+int interpret_branch_name(const char *name, int namelen, struct strbuf *buf)
 {
        char *cp;
        struct branch *upstream;
-       int namelen = strlen(name);
        int len = interpret_nth_prior_checkout(name, buf);
        int tmp_len;
 
+       if (!namelen)
+               namelen = strlen(name);
+
        if (!len) {
                return len; /* syntax Ok, not enough switches */
        } else if (len > 0) {
@@ -1066,9 +1092,15 @@ int interpret_branch_name(const char *name, struct strbuf *buf)
        cp = strchr(name, '@');
        if (!cp)
                return -1;
+
+       len = interpret_empty_at(name, namelen, cp - name, buf);
+       if (len > 0)
+               return reinterpret(name, namelen, len, buf);
+
        tmp_len = upstream_mark(cp, namelen - (cp - name));
        if (!tmp_len)
                return -1;
+
        len = cp + tmp_len - name;
        cp = xstrndup(name, cp - name);
        upstream = branch_get(*cp ? cp : NULL);
@@ -1100,7 +1132,7 @@ int interpret_branch_name(const char *name, struct strbuf *buf)
 int strbuf_branchname(struct strbuf *sb, const char *name)
 {
        int len = strlen(name);
-       int used = interpret_branch_name(name, sb);
+       int used = interpret_branch_name(name, len, sb);
 
        if (used == len)
                return 0;