Add config read fns with controlled error behavior

This adds `git_config__lookup_entry` which will look up a key in
a config and return either the entry or NULL if the key was not
present.  Optionally, it can either suppress all errors or can
return them (although not finding the key is not an error for this
function).  Unlike other accessors, this does not normalize the
config key string, so it must only be used when the key is known
to be in normalized form (i.e. all lower-case before the first dot
and after the last dot, with no invalid characters).

This also adds three high-level helper functions to look up config
values with no errors and a fallback value.  The three functions
are for string, bool, and int values, and will resort to the
fallback value for any error that arises.  They are:

* `git_config__get_string_force`
* `git_config__get_bool_force`
* `git_config__get_int_force`

None of them normalize the config `key` either, so they can only
be used for internal cases where the key is known to be in normal
format.

14 files changed, 263 insertions, 255 deletions

diff --git a/src/attr.c b/src/attr.c
index 98a328a55..51895b7ac 100644
--- a/src/attr.c
+++ b/src/attr.c
@@ -603,11 +603,15 @@ static int attr_cache__lookup_path(
 {
 	git_buf buf = GIT_BUF_INIT;
 	int error;
-	const char *cfgval = NULL;
+	const git_config_entry *entry = NULL;
 
 	*out = NULL;
 
-	if (!(error = git_config_get_string(&cfgval, cfg, key))) {
+	if ((error = git_config__lookup_entry(&entry, cfg, key, false)) < 0)
+		return error;
+
+	if (entry) {
+		const char *cfgval = entry->value;
 
 		/* expand leading ~/ as needed */
 		if (cfgval && cfgval[0] == '~' && cfgval[1] == '/' &&
@@ -616,13 +620,9 @@ static int attr_cache__lookup_path(
 		else if (cfgval)
 			*out = git__strdup(cfgval);
 
-	} else if (error == GIT_ENOTFOUND) {
-		giterr_clear();
-		error = 0;
-
-		if (!git_futils_find_xdg_file(&buf, fallback))
-			*out = git_buf_detach(&buf);
 	}
+	else if (!git_futils_find_xdg_file(&buf, fallback))
+		*out = git_buf_detach(&buf);
 
 	git_buf_free(&buf);
 
diff --git a/src/config.c b/src/config.c
index 0d9471383..227adbc9b 100644
--- a/src/config.c
+++ b/src/config.c
@@ -620,6 +620,78 @@ int git_config_set_string(git_config *cfg, const char *name, const char *value)
 /***********
  * Getters
  ***********/
+
+static int config_error_notfound(const char *name)
+{
+	giterr_set(GITERR_CONFIG, "Config value '%s' was not found", name);
+	return GIT_ENOTFOUND;
+}
+
+enum {
+	GET_ALL_ERRORS = 0,
+	GET_NO_MISSING = 1,
+	GET_NO_ERRORS  = 2
+};
+
+static int get_entry(
+	const git_config_entry **out,
+	const git_config *cfg,
+	const char *name,
+	bool normalize_name,
+	int want_errors)
+{
+	int res = GIT_ENOTFOUND;
+	const char *key = name;
+	char *normalized = NULL;
+	size_t i;
+	file_internal *internal;
+
+	*out = NULL;
+
+	if (normalize_name) {
+		if ((res = git_config__normalize_name(name, &normalized)) < 0)
+			goto cleanup;
+		key = normalized;
+	}
+
+	git_vector_foreach(&cfg->files, i, internal) {
+		if (!internal || !internal->file)
+			continue;
+
+		res = internal->file->get(internal->file, key, out);
+		if (res != GIT_ENOTFOUND)
+			break;
+	}
+
+	git__free(normalized);
+
+cleanup:
+	if (res == GIT_ENOTFOUND)
+		res = (want_errors > GET_ALL_ERRORS) ? 0 : config_error_notfound(name);
+	else if (res && (want_errors == GET_NO_ERRORS)) {
+		giterr_clear();
+		res = 0;
+	}
+
+	return res;
+}
+
+int git_config_get_entry(
+	const git_config_entry **out, const git_config *cfg, const char *name)
+{
+	return get_entry(out, cfg, name, true, GET_ALL_ERRORS);
+}
+
+int git_config__lookup_entry(
+	const git_config_entry **out,
+	const git_config *cfg,
+	const char *key,
+	bool no_errors)
+{
+	return get_entry(
+		out, cfg, key, false, no_errors ? GET_NO_ERRORS : GET_NO_MISSING);
+}
+
 int git_config_get_mapped(
 	int *out,
 	const git_config *cfg,
@@ -627,116 +699,91 @@ int git_config_get_mapped(
 	const git_cvar_map *maps,
 	size_t map_n)
 {
-	const char *value;
+	const git_config_entry *entry;
 	int ret;
 
-	if ((ret = git_config_get_string(&value, cfg, name)) < 0)
+	if ((ret = get_entry(&entry, cfg, name, true, GET_ALL_ERRORS)) < 0)
 		return ret;
 
-	return git_config_lookup_map_value(out, maps, map_n, value);
+	return git_config_lookup_map_value(out, maps, map_n, entry->value);
 }
 
 int git_config_get_int64(int64_t *out, const git_config *cfg, const char *name)
 {
-	const char *value;
+	const git_config_entry *entry;
 	int ret;
 
-	if ((ret = git_config_get_string(&value, cfg, name)) < 0)
+	if ((ret = get_entry(&entry, cfg, name, true, GET_ALL_ERRORS)) < 0)
 		return ret;
 
-	return git_config_parse_int64(out, value);
+	return git_config_parse_int64(out, entry->value);
 }
 
 int git_config_get_int32(int32_t *out, const git_config *cfg, const char *name)
 {
-	const char *value;
+	const git_config_entry *entry;
 	int ret;
 
-	if ((ret = git_config_get_string(&value, cfg, name)) < 0)
+	if ((ret = get_entry(&entry, cfg, name, true, GET_ALL_ERRORS)) < 0)
 		return ret;
 
-	return git_config_parse_int32(out, value);
+	return git_config_parse_int32(out, entry->value);
 }
 
-static int get_string_at_file(const char **out, const git_config_backend *file, const char *name)
+int git_config_get_bool(int *out, const git_config *cfg, const char *name)
 {
 	const git_config_entry *entry;
-	int res;
+	int ret;
 
-	res = file->get(file, name, &entry);
-	if (!res)
-		*out = entry->value;
+	if ((ret = get_entry(&entry, cfg, name, true, GET_ALL_ERRORS)) < 0)
+		return ret;
 
-	return res;
+	return git_config_parse_bool(out, entry->value);
 }
 
-static int config_error_notfound(const char *name)
+int git_config_get_string(
+	const char **out, const git_config *cfg, const char *name)
 {
-	giterr_set(GITERR_CONFIG, "Config value '%s' was not found", name);
-	return GIT_ENOTFOUND;
+	const git_config_entry *entry;
+	int ret = get_entry(&entry, cfg, name, true, GET_ALL_ERRORS);
+	*out = !ret ? (entry->value ? entry->value : "") : NULL;
+	return ret;
 }
 
-static int get_string(const char **out, const git_config *cfg, const char *name)
+const char *git_config__get_string_force(
+	const git_config *cfg, const char *key, const char *fallback_value)
 {
-	file_internal *internal;
-	unsigned int i;
-	int res;
-
-	git_vector_foreach(&cfg->files, i, internal) {
-		if (!internal || !internal->file)
-			continue;
-
-		res = get_string_at_file(out, internal->file, name);
-		if (res != GIT_ENOTFOUND)
-			return res;
-	}
-
-	return config_error_notfound(name);
+	const git_config_entry *entry;
+	get_entry(&entry, cfg, key, false, GET_NO_ERRORS);
+	return (entry && entry->value) ? entry->value : fallback_value;
 }
 
-int git_config_get_bool(int *out, const git_config *cfg, const char *name)
+int git_config__get_bool_force(
+	const git_config *cfg, const char *key, int fallback_value)
 {
-	const char *value = NULL;
-	int ret;
-
-	if ((ret = get_string(&value, cfg, name)) < 0)
-		return ret;
-
-	return git_config_parse_bool(out, value);
-}
+	int val = fallback_value;
+	const git_config_entry *entry;
 
-int git_config_get_string(const char **out, const git_config *cfg, const char *name)
-{
-	int ret;
-	const char *str = NULL;
+	get_entry(&entry, cfg, key, false, GET_NO_ERRORS);
 
-	if ((ret = get_string(&str, cfg, name)) < 0)
-		return ret;
+	if (entry && git_config_parse_bool(&val, entry->value) < 0)
+		giterr_clear();
 
-	*out = str == NULL ? "" : str;
-	return 0;
+	return val;
 }
 
-int git_config_get_entry(const git_config_entry **out, const git_config *cfg, const char *name)
+int git_config__get_int_force(
+	const git_config *cfg, const char *key, int fallback_value)
 {
-	file_internal *internal;
-	unsigned int i;
-	git_config_backend *file;
-	int ret;
-
-	*out = NULL;
+	int32_t val = (int32_t)fallback_value;
+	const git_config_entry *entry;
 
-	git_vector_foreach(&cfg->files, i, internal) {
-		if (!internal || !internal->file)
-			continue;
-		file = internal->file;
+	get_entry(&entry, cfg, key, false, GET_NO_ERRORS);
 
-		ret = file->get(file, name, out);
-		if (ret != GIT_ENOTFOUND)
-			return ret;
-	}
+	if (entry && git_config_parse_int32(&val, entry->value) < 0)
+		giterr_clear();
 
-	return config_error_notfound(name);
+	return (int)val;
 }
 
 int git_config_get_multivar_foreach(
@@ -1070,7 +1117,7 @@ int git_config_parse_int64(int64_t *out, const char *value)
 	const char *num_end;
 	int64_t num;
 
-	if (git__strtol64(&num, value, &num_end, 0) < 0)
+	if (!value || git__strtol64(&num, value, &num_end, 0) < 0)
 		goto fail_parse;
 
 	switch (*num_end) {
diff --git a/src/config.h b/src/config.h
index 01e8465cc..3cd888c88 100644
--- a/src/config.h
+++ b/src/config.h
@@ -51,5 +51,26 @@ extern int git_config_file__ondisk(git_config_backend **out, const char *path);
 
 extern int git_config__normalize_name(const char *in, char **out);
 
+/* internal only: does not normalize key and sets out to NULL if not found */
+extern int git_config__lookup_entry(
+	const git_config_entry **out,
+	const git_config *cfg,
+	const char *key,
+	bool no_errors);
+
+/*
+ * Lookup functions that cannot fail.  These functions look up a config
+ * value and return a fallback value if the value is missing or if any
+ * failures occur while trying to access the value.
+ */
+
+extern const char *git_config__get_string_force(
+	const git_config *cfg, const char *key, const char *fallback_value);
+
+extern int git_config__get_bool_force(
+	const git_config *cfg, const char *key, int fallback_value);
+
+extern int git_config__get_int_force(
+	const git_config *cfg, const char *key, int fallback_value);
 
 #endif
diff --git a/src/config_cache.c b/src/config_cache.c
index 6808521a3..ec75d1501 100644
--- a/src/config_cache.c
+++ b/src/config_cache.c
@@ -78,22 +78,22 @@ int git_repository__cvar(int *out, git_repository *repo, git_cvar_cached cvar)
 		struct map_data *data = &_cvar_maps[(int)cvar];
 		git_config *config;
 		int error;
+		const git_config_entry *entry;
 
-		error = git_repository_config__weakptr(&config, repo);
-		if (error < 0)
+		if ((error = git_repository_config__weakptr(&config, repo)) < 0)
 			return error;
 
-		if (data->maps)
-			error = git_config_get_mapped(
-				out, config, data->cvar_name, data->maps, data->map_count);
-		else
-			error = git_config_get_bool(out, config, data->cvar_name);
+		git_config__lookup_entry(&entry, config, data->cvar_name, false);
 
-		if (error == GIT_ENOTFOUND) {
-			giterr_clear();
+		if (!entry)
 			*out = data->default_value;
-		}
-		else if (error < 0)
+		else if (data->maps)
+			error = git_config_lookup_map_value(
+				out, data->maps, data->map_count, entry->value);
+		else
+			error = git_config_parse_bool(out, entry->value);
+
+		if (error < 0)
 			return error;
 
 		repo->cvar_cache[(int)cvar] = *out;
diff --git a/src/config_file.c b/src/config_file.c
index 15c8de49c..0971aa7b0 100644
--- a/src/config_file.c
+++ b/src/config_file.c
@@ -404,20 +404,12 @@ static int config_set(git_config_backend *cfg, const char *name, const char *val
 /*
  * Internal function that actually gets the value in string form
  */
-static int config_get(const git_config_backend *cfg, const char *name, const git_config_entry **out)
+static int config_get(const git_config_backend *cfg, const char *key, const git_config_entry **out)
 {
 	diskfile_backend *b = (diskfile_backend *)cfg;
-	char *key;
-	khiter_t pos;
-	int error;
+	khiter_t pos = git_strmap_lookup_index(b->values, key);
 	cvar_t *var;
 
-	if ((error = git_config__normalize_name(name, &key)) < 0)
-		return error;
-
-	pos = git_strmap_lookup_index(b->values, key);
-	git__free(key);
-
 	/* no error message; the config system will write one */
 	if (!git_strmap_valid_index(b->values, pos))
 		return GIT_ENOTFOUND;
@@ -427,7 +419,6 @@ static int config_get(const git_config_backend *cfg, const char *name, const git
 		var = var->next;
 
 	*out = var->entry;
-
 	return 0;
 }
 
diff --git a/src/diff.c b/src/diff.c
index 4c33a0213..53a8f4638 100644
--- a/src/diff.c
+++ b/src/diff.c
@@ -304,26 +304,6 @@ bool git_diff_delta__should_skip(
 }
 
 
-static int config_bool(git_config *cfg, const char *name, int defvalue)
-{
-	int val = defvalue;
-
-	if (git_config_get_bool(&val, cfg, name) < 0)
-		giterr_clear();
-
-	return val;
-}
-
-static int config_int(git_config *cfg, const char *name, int defvalue)
-{
-	int val = defvalue;
-
-	if (git_config_get_int32(&val, cfg, name) < 0)
-		giterr_clear();
-
-	return val;
-}
-
 static const char *diff_mnemonic_prefix(
 	git_iterator_type_t type, bool left_side)
 {
@@ -422,8 +402,8 @@ static int diff_list_apply_options(
 		diff->opts.flags |= GIT_DIFF_INCLUDE_UNTRACKED;
 
 	/* load config values that affect diff behavior */
-	if (git_repository_config__weakptr(&cfg, repo) < 0)
-		return -1;
+	if ((val = git_repository_config__weakptr(&cfg, repo)) < 0)
+		return val;
 
 	if (!git_repository__cvar(&val, repo, GIT_CVAR_SYMLINKS) && val)
 		diff->diffcaps = diff->diffcaps | GIT_DIFFCAPS_HAS_SYMLINKS;
@@ -445,7 +425,7 @@ static int diff_list_apply_options(
 
 	/* If not given explicit `opts`, check `diff.xyz` configs */
 	if (!opts) {
-		int context = config_int(cfg, "diff.context", 3);
+		int context = git_config__get_int_force(cfg, "diff.context", 3);
 		diff->opts.context_lines = context >= 0 ? (uint16_t)context : 3;
 
 		/* add other defaults here */
@@ -460,12 +440,11 @@ static int diff_list_apply_options(
 
 	/* if ignore_submodules not explicitly set, check diff config */
 	if (diff->opts.ignore_submodules <= 0) {
-		const char *str;
+		const git_config_entry *entry;
+		git_config__lookup_entry(&entry, cfg, "diff.ignoresubmodules", true);
 
-		if (git_config_get_string(&str , cfg, "diff.ignoreSubmodules") < 0)
-			giterr_clear();
-		else if (str != NULL &&
-			git_submodule_parse_ignore(&diff->opts.ignore_submodules, str) < 0)
+		if (entry && git_submodule_parse_ignore(
+				&diff->opts.ignore_submodules, entry->value) < 0)
 			giterr_clear();
 	}
 
@@ -474,9 +453,9 @@ static int diff_list_apply_options(
 		const char *use_old = DIFF_OLD_PREFIX_DEFAULT;
 		const char *use_new = DIFF_NEW_PREFIX_DEFAULT;
 
-		if (config_bool(cfg, "diff.noprefix", 0)) {
+		if (git_config__get_bool_force(cfg, "diff.noprefix", 0))
 			use_old = use_new = "";
-		} else if (config_bool(cfg, "diff.mnemonicprefix", 0)) {
+		else if (git_config__get_bool_force(cfg, "diff.mnemonicprefix", 0)) {
 			use_old = diff_mnemonic_prefix(diff->old_src, true);
 			use_new = diff_mnemonic_prefix(diff->new_src, false);
 		}
diff --git a/src/diff_driver.c b/src/diff_driver.c
index bd5a8fbd9..167c0cc5a 100644
--- a/src/diff_driver.c
+++ b/src/diff_driver.c
@@ -14,6 +14,7 @@
 #include "strmap.h"
 #include "map.h"
 #include "buf_text.h"
+#include "config.h"
 #include "repository.h"
 
 GIT__USE_STRMAP;
@@ -130,14 +131,14 @@ static git_diff_driver_registry *git_repository_driver_registry(
 static int git_diff_driver_load(
 	git_diff_driver **out, git_repository *repo, const char *driver_name)
 {
-	int error = 0, bval;
+	int error = 0;
 	git_diff_driver_registry *reg;
 	git_diff_driver *drv;
 	size_t namelen = strlen(driver_name);
 	khiter_t pos;
 	git_config *cfg;
 	git_buf name = GIT_BUF_INIT;
-	const char *val;
+	const git_config_entry *ce;
 	bool found_driver = false;
 
 	reg = git_repository_driver_registry(repo);
@@ -164,23 +165,21 @@ static int git_diff_driver_load(
 
 	if ((error = git_buf_printf(&name, "diff.%s.binary", driver_name)) < 0)
 		goto done;
-	if ((error = git_config_get_string(&val, cfg, name.ptr)) < 0) {
-		if (error != GIT_ENOTFOUND)
-			goto done;
-		/* diff.<driver>.binary unspecified, so just continue */
-		giterr_clear();
-	} else if (git_config_parse_bool(&bval, val) < 0) {
-		/* TODO: warn that diff.<driver>.binary has invalid value */
-		giterr_clear();
-	} else if (bval) {
+
+	switch (git_config__get_bool_force(cfg, name.ptr, -1)) {
+	case true:
 		/* if diff.<driver>.binary is true, just return the binary driver */
 		*out = &global_drivers[DIFF_DRIVER_BINARY];
 		goto done;
-	} else {
+	case false:
 		/* if diff.<driver>.binary is false, force binary checks off */
 		/* but still may have custom function context patterns, etc. */
 		drv->binary_flags = GIT_DIFF_FORCE_TEXT;
 		found_driver = true;
+		break;
+	default:
+		/* diff.<driver>.binary unspecified, so just continue */
+		break;
 	}
 
 	/* TODO: warn if diff.<name>.command or diff.<name>.textconv are set */
@@ -211,16 +210,16 @@ static int git_diff_driver_load(
 
 	git_buf_truncate(&name, namelen + strlen("diff.."));
 	git_buf_put(&name, "wordregex", strlen("wordregex"));
-	if ((error = git_config_get_string(&val, cfg, name.ptr)) < 0) {
-		if (error != GIT_ENOTFOUND)
-			goto done;
-		giterr_clear(); /* no diff.<driver>.wordregex, so just continue */
-	} else if ((error = regcomp(&drv->word_pattern, val, REG_EXTENDED)) != 0) {
-		/* TODO: warning about bad regex instead of failure */
-		error = giterr_set_regex(&drv->word_pattern, error);
+	if ((error = git_config__lookup_entry(&ce, cfg, name.ptr, false)) < 0)
 		goto done;
-	} else {
+	if (!ce || !ce->value)
+		/* no diff.<driver>.wordregex, so just continue */;
+	else if (!(error = regcomp(&drv->word_pattern, ce->value, REG_EXTENDED)))
 		found_driver = true;
+	else {
+		/* TODO: warn about bad regex instead of failure */
+		error = giterr_set_regex(&drv->word_pattern, error);
+		goto done;
 	}
 
 	/* TODO: look up diff.<driver>.algorithm to turn on minimal / patience
diff --git a/src/diff_tform.c b/src/diff_tform.c
index 702e43bd3..2f94b2e77 100644
--- a/src/diff_tform.c
+++ b/src/diff_tform.c
@@ -13,6 +13,7 @@
 #include "hashsig.h"
 #include "path.h"
 #include "fileops.h"
+#include "config.h"
 
 static git_diff_delta *diff_delta__dup(
 	const git_diff_delta *d, git_pool *pool)
@@ -290,19 +291,16 @@ static int normalize_find_opts(
 	if (!given ||
 		 (given->flags & GIT_DIFF_FIND_ALL) == GIT_DIFF_FIND_BY_CONFIG)
 	{
-		const char *val = NULL;
-
-		if (git_config_get_string(&val, cfg, "diff.renames") < 0)
-			giterr_clear();
-		else if (val) {
-			int boolval;
-			if (!git__parse_bool(&boolval, val) && !boolval) {
-				/* do nothing */
-			} else if (!strcasecmp(val, "copies") || !strcasecmp(val, "copy"))
-				opts->flags |= (GIT_DIFF_FIND_RENAMES | GIT_DIFF_FIND_COPIES);
-			else
-				opts->flags |= GIT_DIFF_FIND_RENAMES;
-		}
+		const char *rule =
+			git_config__get_string_force(cfg, "diff.renames", "true");
+		int boolval;
+
+		if (!git__parse_bool(&boolval, rule) && !boolval)
+			/* don't set FIND_RENAMES if bool value is false */;
+		else if (!strcasecmp(rule, "copies") || !strcasecmp(rule, "copy"))
+			opts->flags |= GIT_DIFF_FIND_RENAMES | GIT_DIFF_FIND_COPIES;
+		else
+			opts->flags |= GIT_DIFF_FIND_RENAMES;
 	}
 
 	/* some flags imply others */
@@ -343,14 +341,11 @@ static int normalize_find_opts(
 #undef USE_DEFAULT
 
 	if (!opts->rename_limit) {
-		int32_t limit = 0;
-
-		opts->rename_limit = DEFAULT_RENAME_LIMIT;
+		opts->rename_limit = git_config__get_int_force(
+			cfg, "diff.renamelimit", DEFAULT_RENAME_LIMIT);
 
-		if (git_config_get_int32(&limit, cfg, "diff.renameLimit") < 0)
-			giterr_clear();
-		else if (limit > 0)
-			opts->rename_limit = limit;
+		if (opts->rename_limit <= 0)
+			opts->rename_limit = DEFAULT_RENAME_LIMIT;
 	}
 
 	/* assign the internal metric with whitespace flag as payload */
diff --git a/src/merge.c b/src/merge.c
index 45387d4ad..e552b037b 100644
--- a/src/merge.c
+++ b/src/merge.c
@@ -26,6 +26,7 @@
 #include "oid.h"
 #include "index.h"
 #include "filebuf.h"
+#include "config.h"
 
 #include "git2/types.h"
 #include "git2/repository.h"
@@ -1396,19 +1397,13 @@ static int merge_tree_normalize_opts(
 	}
 
 	if (!opts->target_limit) {
-		int32_t limit = 0;
+		int limit = git_config__get_int_force(cfg, "merge.renamelimit", 0);
 
-		opts->target_limit = GIT_MERGE_TREE_TARGET_LIMIT;
+		if (!limit)
+			limit = git_config__get_int_force(cfg, "diff.renamelimit", 0);
 
-		if (git_config_get_int32(&limit, cfg, "merge.renameLimit") < 0) {
-			giterr_clear();
-
-			if (git_config_get_int32(&limit, cfg, "diff.renameLimit") < 0)
-				giterr_clear();
-		}
-
-		if (limit > 0)
-			opts->target_limit = limit;
+		opts->target_limit = (limit <= 0) ?
+			GIT_MERGE_TREE_TARGET_LIMIT : (unsigned int)limit;
 	}
 
 	/* assign the internal metric with whitespace flag as payload */
diff --git a/src/notes.c b/src/notes.c
index beace1b50..d8ed32f82 100644
--- a/src/notes.c
+++ b/src/notes.c
@@ -378,20 +378,11 @@ cleanup:
 
 static int note_get_default_ref(const char **out, git_repository *repo)
 {
-	int ret;
 	git_config *cfg;
+	int ret = git_repository_config__weakptr(&cfg, repo);
 
-	*out = NULL;
-
-	if (git_repository_config__weakptr(&cfg, repo) < 0)
-		return -1;
-
-	ret = git_config_get_string(out, cfg, "core.notesRef");
-	if (ret == GIT_ENOTFOUND) {
-		giterr_clear();
-		*out = GIT_NOTES_DEFAULT_REF;
-		return 0;
-	}
+	*out = (ret != 0) ? NULL : git_config__get_string_force(
+		cfg, "core.notesref", GIT_NOTES_DEFAULT_REF);
 
 	return ret;
 }
diff --git a/src/remote.c b/src/remote.c
index 3d890a5f1..6f86a4b57 100644
--- a/src/remote.c
+++ b/src/remote.c
@@ -45,7 +45,7 @@ static int add_refspec(git_remote *remote, const char *string, bool is_fetch)
 
 static int download_tags_value(git_remote *remote, git_config *cfg)
 {
-	const char *val;
+	const git_config_entry *ce;
 	git_buf buf = GIT_BUF_INIT;
 	int error;
 
@@ -53,16 +53,14 @@ static int download_tags_value(git_remote *remote, git_config *cfg)
 	if (git_buf_printf(&buf, "remote.%s.tagopt", remote->name) < 0)
 		return -1;
 
-	error = git_config_get_string(&val, cfg, git_buf_cstr(&buf));
+	error = git_config__lookup_entry(&ce, cfg, git_buf_cstr(&buf), false);
 	git_buf_free(&buf);
-	if (!error && !strcmp(val, "--no-tags"))
-		remote->download_tags = GIT_REMOTE_DOWNLOAD_TAGS_NONE;
-	else if (!error && !strcmp(val, "--tags"))
-		remote->download_tags = GIT_REMOTE_DOWNLOAD_TAGS_ALL;
 
-	if (error == GIT_ENOTFOUND) {
-		giterr_clear();
-		error = 0;
+	if (!error && ce && ce->value) {
+		if (!strcmp(ce->value, "--no-tags"))
+			remote->download_tags = GIT_REMOTE_DOWNLOAD_TAGS_NONE;
+		else if (!strcmp(ce->value, "--tags"))
+			remote->download_tags = GIT_REMOTE_DOWNLOAD_TAGS_ALL;
 	}
 
 	return error;
@@ -104,12 +102,7 @@ static int get_check_cert(int *out, git_repository *repo)
 	if ((error = git_repository_config__weakptr(&cfg, repo)) < 0)
 		return error;
 
-	if ((error = git_config_get_bool(out, cfg, "http.sslVerify")) == 0)
-		return 0;
-	else if (error != GIT_ENOTFOUND)
-		return error;
-
-	giterr_clear();
+	*out = git_config__get_bool_force(cfg, "http.sslverify", 1);
 	return 0;
 }
 
@@ -493,7 +486,7 @@ int git_remote_save(const git_remote *remote)
 		}
 		if (error < 0) {
 			git_buf_free(&buf);
-			return -1;
+			return error;
 		}
 	}
 
@@ -667,7 +660,8 @@ int git_remote_ls(const git_remote_head ***out, size_t *size, git_remote *remote
 int git_remote__get_http_proxy(git_remote *remote, bool use_ssl, char **proxy_url)
 {
 	git_config *cfg;
-	const char *val;
+	const git_config_entry *ce;
+	const char *val = NULL;
 	int error;
 
 	assert(remote);
@@ -684,44 +678,39 @@ int git_remote__get_http_proxy(git_remote *remote, bool use_ssl, char **proxy_ur
 	 * to least specific. */
 
 	/* remote.<name>.proxy config setting */
-	if (remote->name && 0 != *(remote->name)) {
+	if (remote->name && remote->name[0]) {
 		git_buf buf = GIT_BUF_INIT;
 
 		if ((error = git_buf_printf(&buf, "remote.%s.proxy", remote->name)) < 0)
 			return error;
 
-		if ((error = git_config_get_string(&val, cfg, git_buf_cstr(&buf))) == 0 &&
-			val && ('\0' != *val)) {
-			git_buf_free(&buf);
+		error = git_config__lookup_entry(&ce, cfg, git_buf_cstr(&buf), false);
+		git_buf_free(&buf);
 
-			*proxy_url = git__strdup(val);
-			GITERR_CHECK_ALLOC(*proxy_url);
-			return 0;
-		} else if (error != GIT_ENOTFOUND)
+		if (error < 0)
 			return error;
 
-		giterr_clear();
-		git_buf_free(&buf);
+		if (ce && ce->value) {
+			val = ce->value;
+			goto found;
+		}
 	}
 
 	/* http.proxy config setting */
-	if ((error = git_config_get_string(&val, cfg, "http.proxy")) == 0 &&
-		val && ('\0' != *val)) {
-		*proxy_url = git__strdup(val);
-		GITERR_CHECK_ALLOC(*proxy_url);
-		return 0;
-	} else if (error != GIT_ENOTFOUND)
+	if ((error = git_config__lookup_entry(&ce, cfg, "http.proxy", false)) < 0)
 		return error;
-
-	giterr_clear();
+	if (ce && ce->value) {
+		val = ce->value;
+		goto found;
+	}
 
 	/* HTTP_PROXY / HTTPS_PROXY environment variables */
 	val = use_ssl ? getenv("HTTPS_PROXY") : getenv("HTTP_PROXY");
 
-	if (val && ('\0' != *val)) {
+found:
+	if (val && val[0]) {
 		*proxy_url = git__strdup(val);
 		GITERR_CHECK_ALLOC(*proxy_url);
-		return 0;
 	}
 
 	return 0;
diff --git a/src/repository.c b/src/repository.c
index 278c0384e..443744504 100644
--- a/src/repository.c
+++ b/src/repository.c
@@ -186,39 +186,37 @@ static int load_workdir(git_repository *repo, git_buf *parent_path)
 {
 	int         error;
 	git_config *config;
-	const char *worktree;
-	git_buf     worktree_buf = GIT_BUF_INIT;
+	const git_config_entry *ce;
+	git_buf     worktree = GIT_BUF_INIT;
 
 	if (repo->is_bare)
 		return 0;
 
-	if (git_repository_config__weakptr(&config, repo) < 0)
-		return -1;
+	if ((error = git_repository_config__weakptr(&config, repo)) < 0)
+		return error;
 
-	error = git_config_get_string(&worktree, config, "core.worktree");
-	if (!error && worktree != NULL) {
-		error = git_path_prettify_dir(
-			&worktree_buf, worktree, repo->path_repository);
-		if (error < 0)
+	if ((error = git_config__lookup_entry(
+			&ce, config, "core.worktree", false)) < 0)
+		return error;
+
+	if (ce && ce->value) {
+		if ((error = git_path_prettify_dir(
+				&worktree, ce->value, repo->path_repository)) < 0)
 			return error;
-		repo->workdir = git_buf_detach(&worktree_buf);
+
+		repo->workdir = git_buf_detach(&worktree);
 	}
-	else if (error != GIT_ENOTFOUND)
-		return error;
+	else if (parent_path && git_path_isdir(parent_path->ptr))
+		repo->workdir = git_buf_detach(parent_path);
 	else {
-		giterr_clear();
+		if (git_path_dirname_r(&worktree, repo->path_repository) < 0 ||
+			git_path_to_dir(&worktree) < 0)
+			return -1;
 
-		if (parent_path && git_path_isdir(parent_path->ptr))
-			repo->workdir = git_buf_detach(parent_path);
-		else {
-			git_path_dirname_r(&worktree_buf, repo->path_repository);
-			git_path_to_dir(&worktree_buf);
-			repo->workdir = git_buf_detach(&worktree_buf);
-		}
+		repo->workdir = git_buf_detach(&worktree);
 	}
 
 	GITERR_CHECK_ALLOC(repo->workdir);
-
 	return 0;
 }
 
diff --git a/src/submodule.c b/src/submodule.c
index 586494fed..1e3d07911 100644
--- a/src/submodule.c
+++ b/src/submodule.c
@@ -1468,7 +1468,7 @@ static int submodule_update_config(
 	int error;
 	git_config *config;
 	git_buf key = GIT_BUF_INIT;
-	const char *old = NULL;
+	const git_config_entry *ce = NULL;
 
 	assert(submodule);
 
@@ -1480,14 +1480,16 @@ static int submodule_update_config(
 	if (error < 0)
 		goto cleanup;
 
-	if (git_config_get_string(&old, config, key.ptr) < 0)
-		giterr_clear();
+	if ((error = git_config__lookup_entry(&ce, config, key.ptr, false)) < 0)
+		goto cleanup;
 
-	if (!old && only_existing)
+	if (!ce && only_existing)
+		goto cleanup;
+	if (ce && !overwrite)
 		goto cleanup;
-	if (old && !overwrite)
+	if (value && ce && ce->value && !strcmp(ce->value, value))
 		goto cleanup;
-	if ((!old && !value) || (old && value && strcmp(old, value) == 0))
+	if (!value && (!ce || !ce->value))
 		goto cleanup;
 
 	if (!value)
diff --git a/src/transports/local.c b/src/transports/local.c
index 4502f0202..f09e797ce 100644
--- a/src/transports/local.c
+++ b/src/transports/local.c
@@ -250,8 +250,9 @@ static int local_negotiate_fetch(
 			git_oid_cpy(&rhead->loid, git_object_id(obj));
 		else if (error != GIT_ENOTFOUND)
 			return error;
+		else
+			giterr_clear();
 		git_object_free(obj);
-		giterr_clear();
 	}
 
 	return 0;