From: Junio C Hamano <gitster@pobox.com>
Date: Wed, 18 Jan 2017 23:12:16 +0000 (-0800)
Subject: Merge branch 'bw/realpath-wo-chdir'
X-Git-Tag: v2.12.0-rc0~61
X-Git-Url: https://www.git.lorimer.id.au/gitweb.git/diff_plain/1c16df23b19e8d37d896e68c92d8341d6e60b4dc?hp=5918bdcf26030a2540ac25d5b8cbee82fad219fc

Merge branch 'bw/realpath-wo-chdir'

The implementation of "real_path()" was to go there with chdir(2)
and call getcwd(3), but this obviously wouldn't be usable in a
threaded environment.  Rewrite it to manually resolve relative
paths including symbolic links in path components.

* bw/realpath-wo-chdir:
real_path: set errno when max number of symlinks is exceeded
real_path: prevent redefinition of MAXSYMLINKS
---

diff --git a/abspath.c b/abspath.c
index 1d56f5ed9f..fce40fddcc 100644
--- a/abspath.c
+++ b/abspath.c
@@ -62,7 +62,9 @@ static void get_root_part(struct strbuf *resolved, struct strbuf *remaining)
 }
 
 /* We allow "recursive" symbolic links. Only within reason, though. */
-#define MAXSYMLINKS 5
+#ifndef MAXSYMLINKS
+#define MAXSYMLINKS 32
+#endif
 
 /*
  * Return the real path (i.e., absolute path, with symlinks resolved
@@ -139,6 +141,8 @@ char *strbuf_realpath(struct strbuf *resolved, const char *path,
 			strbuf_reset(&symlink);
 
 			if (num_symlinks++ > MAXSYMLINKS) {
+				errno = ELOOP;
+
 				if (die_on_error)
 					die("More than %d nested symlinks "
 					    "on path '%s'", MAXSYMLINKS, path);
diff --git a/dir.c b/dir.c
index 4ac63bc940..65c3e681b8 100644
--- a/dir.c
+++ b/dir.c
@@ -2731,8 +2731,8 @@ void connect_work_tree_and_git_dir(const char *work_tree_, const char *git_dir_)
 {
 	struct strbuf file_name = STRBUF_INIT;
 	struct strbuf rel_path = STRBUF_INIT;
-	char *git_dir = xstrdup(real_path(git_dir_));
-	char *work_tree = xstrdup(real_path(work_tree_));
+	char *git_dir = real_pathdup(git_dir_);
+	char *work_tree = real_pathdup(work_tree_);
 
 	/* Update gitfile */
 	strbuf_addf(&file_name, "%s/.git", work_tree);