config: borrow refcounted references

This changes the get_entry() method to return a refcounted version of
the config entry, which you have to free when you're done.

This allows us to avoid freeing the memory in which the entry is stored
on a refresh, which may happen at any time for a live config.

For this reason, get_string() has been forbidden on live configs and a
new function get_string_buf() has been added, which stores the string in
a git_buf which the user then owns.

The functions which parse the string value takea advantage of the
borrowing to parse safely and then release the entry.

4 files changed, 16 insertions, 36 deletions

diff --git a/tests/submodule/add.c b/tests/submodule/add.c
index 05dbafd88..01625d3aa 100644
--- a/tests/submodule/add.c
+++ b/tests/submodule/add.c
@@ -2,6 +2,7 @@
 #include "posix.h"
 #include "path.h"
 #include "submodule_helpers.h"
+#include "config/config_helpers.h"
 #include "fileops.h"
 
 static git_repository *g_repo = NULL;
@@ -13,26 +14,19 @@ void test_submodule_add__cleanup(void)
 
 static void assert_submodule_url(const char* name, const char *url)
 {
-	git_config *cfg;
-	const char *s;
 	git_buf key = GIT_BUF_INIT;
 
-	cl_git_pass(git_repository_config(&cfg, g_repo));
 
 	cl_git_pass(git_buf_printf(&key, "submodule.%s.url", name));
-	cl_git_pass(git_config_get_string(&s, cfg, git_buf_cstr(&key)));
-	cl_assert_equal_s(s, url);
+	assert_config_entry_value(g_repo, git_buf_cstr(&key), url);
 
-	git_config_free(cfg);
 	git_buf_free(&key);
 }
 
 void test_submodule_add__url_absolute(void)
 {
 	git_submodule *sm;
-	git_config *cfg;
 	git_repository *repo;
-	const char *worktree_path;
 	git_buf dot_git_content = GIT_BUF_INIT;
 
 	g_repo = setup_fixture_submod2();
@@ -59,15 +53,12 @@ void test_submodule_add__url_absolute(void)
 	cl_git_pass(git_repository_open(&repo, "submod2/" "sm_libgit2"));
 
 	/* Verify worktree path is relative */
-	cl_git_pass(git_repository_config(&cfg, repo));
-	cl_git_pass(git_config_get_string(&worktree_path, cfg, "core.worktree"));
-	cl_assert_equal_s("../../../sm_libgit2/", worktree_path);
+	assert_config_entry_value(repo, "core.worktree", "../../../sm_libgit2/");
 
 	/* Verify gitdir path is relative */
 	cl_git_pass(git_futils_readbuffer(&dot_git_content, "submod2/" "sm_libgit2" "/.git"));
 	cl_assert_equal_s("gitdir: ../.git/modules/sm_libgit2/", dot_git_content.ptr);
 
-	git_config_free(cfg);
 	git_repository_free(repo);
 	git_buf_free(&dot_git_content);
 
diff --git a/tests/submodule/init.c b/tests/submodule/init.c
index 3db6dae61..dbde0f284 100644
--- a/tests/submodule/init.c
+++ b/tests/submodule/init.c
@@ -34,9 +34,9 @@ void test_submodule_init__absolute_url(void)
 	/* init and verify that absolute path is written to .git/config */
 	cl_git_pass(git_submodule_init(sm, false));
 
-	cl_git_pass(git_repository_config(&cfg, g_repo));
+	cl_git_pass(git_repository_config_snapshot(&cfg, g_repo));
 
-	git_config_get_string(&config_url, cfg, "submodule.testrepo.url");
+	cl_git_pass(git_config_get_string(&config_url, cfg, "submodule.testrepo.url"));
 	cl_assert_equal_s(absolute_url.ptr, config_url);
 
 	git_buf_free(&absolute_url);
@@ -64,9 +64,9 @@ void test_submodule_init__relative_url(void)
 	/* init and verify that absolute path is written to .git/config */
 	cl_git_pass(git_submodule_init(sm, false));
 
-	cl_git_pass(git_repository_config(&cfg, g_repo));
+	cl_git_pass(git_repository_config_snapshot(&cfg, g_repo));
 
-	git_config_get_string(&config_url, cfg, "submodule.testrepo.url");
+	cl_git_pass(git_config_get_string(&config_url, cfg, "submodule.testrepo.url"));
 	cl_assert_equal_s(absolute_url.ptr, config_url);
 
 	git_buf_free(&absolute_url);
@@ -102,9 +102,9 @@ void test_submodule_init__relative_url_detached_head(void)
 	/* init and verify that absolute path is written to .git/config */
 	cl_git_pass(git_submodule_init(sm, false));
 
-	cl_git_pass(git_repository_config(&cfg, g_repo));
+	cl_git_pass(git_repository_config_snapshot(&cfg, g_repo));
 
-	git_config_get_string(&config_url, cfg, "submodule.testrepo.url");
+	cl_git_pass(git_config_get_string(&config_url, cfg, "submodule.testrepo.url"));
 	cl_assert_equal_s(absolute_url.ptr, config_url);
 
 	git_buf_free(&absolute_url);
diff --git a/tests/submodule/modify.c b/tests/submodule/modify.c
index 9bb48bad2..3d7269bff 100644
--- a/tests/submodule/modify.c
+++ b/tests/submodule/modify.c
@@ -2,6 +2,7 @@
 #include "posix.h"
 #include "path.h"
 #include "submodule_helpers.h"
+#include "config/config_helpers.h"
 
 static git_repository *g_repo = NULL;
 
@@ -51,7 +52,7 @@ void test_submodule_modify__init(void)
 	git_submodule_reload_all(g_repo, 1);
 
 	/* confirm submodule data in config */
-	cl_git_pass(git_repository_config(&cfg, g_repo));
+	cl_git_pass(git_repository_config_snapshot(&cfg, g_repo));
 	cl_git_pass(git_config_get_string(&str, cfg, "submodule.sm_unchanged.url"));
 	cl_assert(git__suffixcmp(str, "/submod2_target") == 0);
 	cl_git_pass(git_config_get_string(&str, cfg, "submodule.sm_changed_head.url"));
@@ -72,20 +73,12 @@ static int sync_one_submodule(
 static void assert_submodule_url_is_synced(
 	git_submodule *sm, const char *parent_key, const char *child_key)
 {
-	git_config *cfg;
-	const char *str;
 	git_repository *smrepo;
 
-	cl_git_pass(git_repository_config(&cfg, g_repo));
-	cl_git_pass(git_config_get_string(&str, cfg, parent_key));
-	cl_assert_equal_s(git_submodule_url(sm), str);
-	git_config_free(cfg);
+	assert_config_entry_value(g_repo, parent_key, git_submodule_url(sm));
 
 	cl_git_pass(git_submodule_open(&smrepo, sm));
-	cl_git_pass(git_repository_config(&cfg, smrepo));
-	cl_git_pass(git_config_get_string(&str, cfg, child_key));
-	cl_assert_equal_s(git_submodule_url(sm), str);
-	git_config_free(cfg);
+	assert_config_entry_value(smrepo, child_key,  git_submodule_url(sm));
 	git_repository_free(smrepo);
 }
 
@@ -111,7 +104,7 @@ void test_submodule_modify__sync(void)
 	 */
 
 	/* check submodule info does not match before sync */
-	cl_git_pass(git_repository_config(&cfg, g_repo));
+	cl_git_pass(git_repository_config_snapshot(&cfg, g_repo));
 	cl_git_pass(git_config_get_string(&str, cfg, "submodule."SM1".url"));
 	cl_assert(strcmp(git_submodule_url(sm1), str) != 0);
 	cl_git_pass(git_config_get_string(&str, cfg, "submodule."SM2".url"));
diff --git a/tests/submodule/repository_init.c b/tests/submodule/repository_init.c
index bf1968d66..9be1e0b23 100644
--- a/tests/submodule/repository_init.c
+++ b/tests/submodule/repository_init.c
@@ -2,6 +2,7 @@
 #include "posix.h"
 #include "path.h"
 #include "submodule_helpers.h"
+#include "config/config_helpers.h"
 #include "fileops.h"
 
 static git_repository *g_repo = NULL;
@@ -10,8 +11,6 @@ void test_submodule_repository_init__basic(void)
 {
 	git_submodule *sm;
 	git_repository *repo;
-	git_config *cfg;
-	const char *worktree_path;
 	git_buf dot_git_content = GIT_BUF_INIT;
 
 	g_repo = setup_fixture_submod2();
@@ -21,9 +20,7 @@ void test_submodule_repository_init__basic(void)
 	cl_git_pass(git_submodule_repo_init(&repo, sm, 1));
 
 	/* Verify worktree */
-	cl_git_pass(git_repository_config(&cfg, repo));
-	cl_git_pass(git_config_get_string(&worktree_path, cfg, "core.worktree"));
-	cl_assert_equal_s("../../../sm_gitmodules_only/", worktree_path);
+	assert_config_entry_value(repo, "core.worktree", "../../../sm_gitmodules_only/");
 
 	/* Verify gitlink */
 	cl_git_pass(git_futils_readbuffer(&dot_git_content, "submod2/" "sm_gitmodules_only" "/.git"));
@@ -35,7 +32,6 @@ void test_submodule_repository_init__basic(void)
 	cl_assert(git_path_isdir("submod2/.git/modules/" "sm_gitmodules_only"));
 	cl_assert(git_path_isfile("submod2/.git/modules/" "sm_gitmodules_only" "/HEAD"));
 
-	git_config_free(cfg);
 	git_submodule_free(sm);
 	git_repository_free(repo);
 	git_buf_free(&dot_git_content);