[PATCH v5 0/7] Rewrite `git_config()` using config-set API

[PATCH v5 0/7] Rewrite `git_config()` using config-set API

[Tanay Abhra]

[PATCH v5]: New patch added (3/7). git_config() now returns void.

[PATCH v4]: One style nit corrected, also added key to error messages.
	Diff with v3 at the bottom for easy review.

[PATCH V3]:All the suggestions in [3] applied. Built on top of [1].

[PATCH V2]: All the suggestions in [2] incorporated. git_config() now follows
	correct parsing order. Reordered the patches. Removed xfuncname patch
	as it was unnecssary.

This series builds on the top of topic[1] in the mailing list with name
"git config cache & special querying API utilizing the cache".

This series aims to do these three things,

* Use the config-set API to rewrite git_config().

* Solve any legacy bugs in the previous system while at it.

* To be feature complete compared to the previous git_config() implementation,
  which I think it is now. (added the line number and file name info just for
  completeness)

Also, I haven't yet checked the exact improvements but still as a teaser,
git status now only rereads the configuration files twice instead of four
times.

[1]: http://thread.gmane.org/gmane.comp.version-control.git/254286
[2]: http://thread.gmane.org/gmane.comp.version-control.git/254101
[3]: http://thread.gmane.org/gmane.comp.version-control.git/254211

Tanay Abhra (7):
  config.c: fix accuracy of line number in errors
  add line number and file name info to `config_set`
  change `git_config()` return value to void
  rewrite git_config() to use the config-set API
  add a test for semantic errors in config files
  config: add `git_die_config()` to the config-set API
  add tests for `git_config_get_string_const()`

 Documentation/technical/api-config.txt |   5 ++
 branch.c                               |   5 +-
 cache.h                                |  27 ++++++-
 config.c                               | 131 +++++++++++++++++++++++++++++----
 t/t1308-config-set.sh                  |  21 ++++++
 t/t4055-diff-context.sh                |   2 +-
 test-config.c                          |  10 +++
 7 files changed, 181 insertions(+), 20 deletions(-)

-- 
1.9.0.GIT

[PATCH v5 1/7] config.c: fix accuracy of line number in errors

[Tanay Abhra]

From: Matthieu Moy <Matthieu.Moy@grenoble-inp.fr>

If a callback returns a negative value to `git_config*()` family,
they call `die()` while printing the line number and the file name.
Currently the printed line number is off by one, thus printing the
wrong line number.

Make `linenr` point to the line we just parsed during the call
to callback to get accurate line number in error messages.

Commit-message-by: Tanay Abhra <tanayabh@gmail.com>
Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
---
 config.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/config.c b/config.c
index a191328..ed5fc8e 100644
--- a/config.c
+++ b/config.c
@@ -244,6 +244,7 @@ static int get_next_char(void)
 		cf->linenr++;
 	if (c == EOF) {
 		cf->eof = 1;
+		cf->linenr++;
 		c = '\n';
 	}
 	return c;
@@ -319,6 +320,7 @@ static int get_value(config_fn_t fn, void *data, struct strbuf *name)
 {
 	int c;
 	char *value;
+	int ret;
 
 	/* Get the full name */
 	for (;;) {
@@ -341,7 +343,15 @@ static int get_value(config_fn_t fn, void *data, struct strbuf *name)
 		if (!value)
 			return -1;
 	}
-	return fn(name->buf, value, data);
+	/*
+	 * We already consumed the \n, but we need linenr to point to
+	 * the line we just parsed during the call to fn to get
+	 * accurate line number in error messages.
+	 */
+	cf->linenr--;
+	ret = fn(name->buf, value, data);
+	cf->linenr++;
+	return ret;
 }
 
 static int get_extended_base_var(struct strbuf *name, int c)
-- 
1.9.0.GIT

[PATCH v5 2/7] add line number and file name info to `config_set`

[Tanay Abhra]

Store file name and line number for each key-value pair in the cache
during parsing of the configuration files.

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
---
 config.c | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/config.c b/config.c
index ed5fc8e..4a15383 100644
--- a/config.c
+++ b/config.c
@@ -1230,6 +1230,11 @@ int git_config_with_options(config_fn_t fn, void *data,
 	return ret;
 }
 
+struct key_value_info {
+	const char *filename;
+	int linenr;
+};
+
 int git_config(config_fn_t fn, void *data)
 {
 	return git_config_with_options(fn, data, NULL, 1);
@@ -1260,6 +1265,9 @@ static struct config_set_element *configset_find_element(struct config_set *cs,
 static int configset_add_value(struct config_set *cs, const char *key, const char *value)
 {
 	struct config_set_element *e;
+	struct string_list_item *si;
+	struct key_value_info *kv_info = xmalloc(sizeof(*kv_info));
+
 	e = configset_find_element(cs, key);
 	/*
 	 * Since the keys are being fed by git_config*() callback mechanism, they
@@ -1272,7 +1280,16 @@ static int configset_add_value(struct config_set *cs, const char *key, const cha
 		string_list_init(&e->value_list, 1);
 		hashmap_add(&cs->config_hash, e);
 	}
-	string_list_append_nodup(&e->value_list, value ? xstrdup(value) : NULL);
+	si = string_list_append_nodup(&e->value_list, value ? xstrdup(value) : NULL);
+	if (cf) {
+		kv_info->filename = strintern(cf->name);
+		kv_info->linenr = cf->linenr;
+	} else {
+		/* for values read from `git_config_from_parameters()` */
+		kv_info->filename = strintern("parameter");
+		kv_info->linenr = 0;
+	}
+	si->util = kv_info;
 
 	return 0;
 }
@@ -1299,7 +1316,7 @@ void git_configset_clear(struct config_set *cs)
 	hashmap_iter_init(&cs->config_hash, &iter);
 	while ((entry = hashmap_iter_next(&iter))) {
 		free(entry->key);
-		string_list_clear(&entry->value_list, 0);
+		string_list_clear(&entry->value_list, 1);
 	}
 	hashmap_free(&cs->config_hash, 1);
 	cs->hash_initialized = 0;
-- 
1.9.0.GIT

[PATCH v5 3/7] change `git_config()` return value to void

[Tanay Abhra]

Currently `git_config()` returns an integer signifying an error code.
During a previous rewrite of the function most of the code was shifted
to `git_config_with_options()`. `git_config_with_options()` normally
returns positive values if its `config_source` parameter is set as NULL,
as most errors are fatal, and non-fatal potential errors are guarded
by "if" statements that are entered only when no error is possible.

Still a negative value can be returned in case of race condition between
`access_or_die()` & `git_config_from_file()`. Also, all callers of
`git_config()` ignore the return value except for one case in branch.c.

Change `git_config()` return value to void and make it die if it receives
a negative return value from `git_config_with_options()`.

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
---
 branch.c |  5 +----
 cache.h  |  2 +-
 config.c | 16 ++++++++++++++--
 3 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/branch.c b/branch.c
index 46e8aa8..735767d 100644
--- a/branch.c
+++ b/branch.c
@@ -161,10 +161,7 @@ int read_branch_desc(struct strbuf *buf, const char *branch_name)
 	strbuf_addf(&name, "branch.%s.description", branch_name);
 	cb.config_name = name.buf;
 	cb.value = NULL;
-	if (git_config(read_branch_desc_cb, &cb) < 0) {
-		strbuf_release(&name);
-		return -1;
-	}
+	git_config(read_branch_desc_cb, &cb);
 	if (cb.value)
 		strbuf_addstr(buf, cb.value);
 	strbuf_release(&name);
diff --git a/cache.h b/cache.h
index 7292aef..c61919d 100644
--- a/cache.h
+++ b/cache.h
@@ -1294,7 +1294,7 @@ extern int git_config_from_buf(config_fn_t fn, const char *name,
 			       const char *buf, size_t len, void *data);
 extern void git_config_push_parameter(const char *text);
 extern int git_config_from_parameters(config_fn_t fn, void *data);
-extern int git_config(config_fn_t fn, void *);
+extern void git_config(config_fn_t fn, void *);
 extern int git_config_with_options(config_fn_t fn, void *,
 				   struct git_config_source *config_source,
 				   int respect_includes);
diff --git a/config.c b/config.c
index 4a15383..c0faaca 100644
--- a/config.c
+++ b/config.c
@@ -1235,9 +1235,21 @@ struct key_value_info {
 	int linenr;
 };
 
-int git_config(config_fn_t fn, void *data)
+void git_config(config_fn_t fn, void *data)
 {
-	return git_config_with_options(fn, data, NULL, 1);
+	if (git_config_with_options(fn, data, NULL, 1) < 0)
+		/*
+		 * git_config_with_options() normally returns only
+		 * positive values, as most errors are fatal, and
+		 * non-fatal potential errors are guarded by "if"
+		 * statements that are entered only when no error is
+		 * possible.
+		 *
+		 * If we ever encounter a non-fatal error, it means
+		 * something went really wrong and we should stop
+		 * immediately.
+		 */
+		die("Unknown error occured while reading the configuration files");
 }
 
 static struct config_set_element *configset_find_element(struct config_set *cs, const char *key)
-- 
1.9.0.GIT

Re: [PATCH v5 3/7] change `git_config()` return value to void

[Matthieu Moy]

Tanay Abhra <tanayabh@gmail.com> writes:

> Signed-off-by: Tanay Abhra <tanayabh@gmail.com>

I think I deserve a bit of credit here ;-).

>  {
> -	return git_config_with_options(fn, data, NULL, 1);
> +	if (git_config_with_options(fn, data, NULL, 1) < 0)
> +		/*
> +		 * git_config_with_options() normally returns only
> +		 * positive values, as most errors are fatal, and
> +		 * non-fatal potential errors are guarded by "if"
> +		 * statements that are entered only when no error is
> +		 * possible.
> +		 *
> +		 * If we ever encounter a non-fatal error, it means
> +		 * something went really wrong and we should stop
> +		 * immediately.
> +		 */
> +		die("Unknown error occured while reading the configuration files");
>  }

My bad, but this should be die(_("..."));, so that the message can be
translated. Not really serious since it's not really meant to be seen by
the user, though.

-- 
Matthieu Moy
http://www-verimag.imag.fr/~moy/

Re: [PATCH v5 3/7] change `git_config()` return value to void

[Matthieu Moy]

Matthieu Moy <Matthieu.Moy@grenoble-inp.fr> writes:

> Tanay Abhra <tanayabh@gmail.com> writes:
>
>> Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
>
> I think I deserve a bit of credit here ;-).
>
>>  {
>> -	return git_config_with_options(fn, data, NULL, 1);
>> +	if (git_config_with_options(fn, data, NULL, 1) < 0)
>> +		/*
>> +		 * git_config_with_options() normally returns only
>> +		 * positive values, as most errors are fatal, and
>> +		 * non-fatal potential errors are guarded by "if"
>> +		 * statements that are entered only when no error is
>> +		 * possible.
>> +		 *
>> +		 * If we ever encounter a non-fatal error, it means
>> +		 * something went really wrong and we should stop
>> +		 * immediately.
>> +		 */
>> +		die("Unknown error occured while reading the configuration files");
>>  }
>
> My bad, but this should be die(_("..."));, so that the message can be
> translated. Not really serious since it's not really meant to be seen by
> the user, though.

Also, other error messages do not start with a capital, hence it should
be "unknown..., not "Unknown. My bad again.

-- 
Matthieu Moy
http://www-verimag.imag.fr/~moy/

Re: [PATCH v5 3/7] change `git_config()` return value to void

[Tanay Abhra]

On 7/31/2014 4:52 PM, Matthieu Moy wrote:
> Tanay Abhra <tanayabh@gmail.com> writes:
> 
>> Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
> 
> I think I deserve a bit of credit here ;-).
>

Yes, but to show credit would I have to write "from you" or
"signed-off-by"? :)

>>  {
>> -	return git_config_with_options(fn, data, NULL, 1);
>> +	if (git_config_with_options(fn, data, NULL, 1) < 0)
>> +		/*
>> +		 * git_config_with_options() normally returns only
>> +		 * positive values, as most errors are fatal, and
>> +		 * non-fatal potential errors are guarded by "if"
>> +		 * statements that are entered only when no error is
>> +		 * possible.
>> +		 *
>> +		 * If we ever encounter a non-fatal error, it means
>> +		 * something went really wrong and we should stop
>> +		 * immediately.
>> +		 */
>> +		die("Unknown error occured while reading the configuration files");
>>  }
> 
> My bad, but this should be die(_("..."));, so that the message can be
> translated. Not really serious since it's not really meant to be seen by
> the user, though.
>

Noted. Though there are not many cases till I have read where error messages are marked
for translation.

Re: [PATCH v5 3/7] change `git_config()` return value to void

[Matthieu Moy]

Tanay Abhra <tanayabh@gmail.com> writes:

> On 7/31/2014 4:52 PM, Matthieu Moy wrote:
>> Tanay Abhra <tanayabh@gmail.com> writes:
>> 
>>> Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
>> 
>> I think I deserve a bit of credit here ;-).
>>
>
> Yes, but to show credit would I have to write "from you" or
> "signed-off-by"? :)

Original-patch-by: would be fine.

>> My bad, but this should be die(_("..."));, so that the message can be
>> translated. Not really serious since it's not really meant to be seen by
>> the user, though.
>>
>
> Noted. Though there are not many cases till I have read where error messages are marked
> for translation.

Yes, see my other message.

Overall, there are still many untranslated messages in Git's codebase:

$ git grep 'die(_("' | wc -l
517
$ git grep 'die("' | wc -l 
1247

Part of the reason is that die() was written and used far before the
translation effort has started.

-- 
Matthieu Moy
http://www-verimag.imag.fr/~moy/

[PATCH v5 4/7] rewrite git_config() to use the config-set API

[Tanay Abhra]

Of all the functions in `git_config*()` family, `git_config()` has the
most invocations in the whole code base. Each `git_config()` invocation
causes config file rereads which can be avoided using the config-set API.

Use the config-set API to rewrite `git_config()` to use the config caching
layer to avoid config file rereads on each invocation during a git process
lifetime. First invocation constructs the cache, and after that for each
successive invocation, `git_config()` feeds values from the config cache
instead of rereading the configuration files.

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
---
 cache.h                 | 24 +++++++++++++++++++++
 config.c                | 57 ++++++++++++++++++++++++++++++++++++++++++-------
 t/t4055-diff-context.sh |  2 +-
 3 files changed, 74 insertions(+), 9 deletions(-)

diff --git a/cache.h b/cache.h
index c61919d..4d3c6bd 100644
--- a/cache.h
+++ b/cache.h
@@ -8,6 +8,7 @@
 #include "gettext.h"
 #include "convert.h"
 #include "trace.h"
+#include "string-list.h"
 
 #include SHA1_HEADER
 #ifndef git_SHA_CTX
@@ -1351,9 +1352,32 @@ extern int parse_config_key(const char *var,
 			    const char **subsection, int *subsection_len,
 			    const char **key);
 
+struct config_set_element {
+	struct hashmap_entry ent;
+	char *key;
+	struct string_list value_list;
+};
+
+struct configset_list_item {
+	struct config_set_element *e;
+	int value_index;
+};
+
+/*
+ * the contents of the list are ordered according to their
+ * position in the config files and order of parsing the files.
+ * (i.e. key-value pair at the last position of .git/config will
+ * be at the last item of the list)
+ */
+struct configset_list {
+	struct configset_list_item *items;
+	unsigned int nr, alloc;
+};
+
 struct config_set {
 	struct hashmap config_hash;
 	int hash_initialized;
+	struct configset_list list;
 };
 
 extern void git_configset_init(struct config_set *cs);
diff --git a/config.c b/config.c
index c0faaca..4937515 100644
--- a/config.c
+++ b/config.c
@@ -35,12 +35,6 @@ struct config_source {
 	long (*do_ftell)(struct config_source *c);
 };
 
-struct config_set_element {
-	struct hashmap_entry ent;
-	char *key;
-	struct string_list value_list;
-};
-
 static struct config_source *cf;
 
 static int zlib_compression_seen;
@@ -1235,7 +1229,7 @@ struct key_value_info {
 	int linenr;
 };
 
-void git_config(config_fn_t fn, void *data)
+static void git_config_raw(config_fn_t fn, void *data)
 {
 	if (git_config_with_options(fn, data, NULL, 1) < 0)
 		/*
@@ -1252,6 +1246,39 @@ void git_config(config_fn_t fn, void *data)
 		die("Unknown error occured while reading the configuration files");
 }
 
+static void configset_iter(struct config_set *cs, config_fn_t fn, void *data)
+{
+	int i, value_index;
+	struct string_list *values;
+	struct config_set_element *entry;
+	struct configset_list *list = &cs->list;
+	struct key_value_info *kv_info;
+
+	for (i = 0; i < list->nr; i++) {
+		entry = list->items[i].e;
+		value_index = list->items[i].value_index;
+		values = &entry->value_list;
+		if (fn(entry->key, values->items[value_index].string, data) < 0) {
+			kv_info = values->items[value_index].util;
+			if (!kv_info->linenr)
+				die("unable to parse '%s' from command-line config", entry->key);
+			else
+				die("bad config variable '%s' at file line %d in %s",
+					entry->key,
+					kv_info->linenr,
+					kv_info->filename);
+		}
+	}
+}
+
+static void git_config_check_init(void);
+
+void git_config(config_fn_t fn, void *data)
+{
+	git_config_check_init();
+	configset_iter(&the_config_set, fn, data);
+}
+
 static struct config_set_element *configset_find_element(struct config_set *cs, const char *key)
 {
 	struct config_set_element k;
@@ -1278,6 +1305,7 @@ static int configset_add_value(struct config_set *cs, const char *key, const cha
 {
 	struct config_set_element *e;
 	struct string_list_item *si;
+	struct configset_list_item *l_item;
 	struct key_value_info *kv_info = xmalloc(sizeof(*kv_info));
 
 	e = configset_find_element(cs, key);
@@ -1293,6 +1321,12 @@ static int configset_add_value(struct config_set *cs, const char *key, const cha
 		hashmap_add(&cs->config_hash, e);
 	}
 	si = string_list_append_nodup(&e->value_list, value ? xstrdup(value) : NULL);
+
+	ALLOC_GROW(cs->list.items, cs->list.nr + 1, cs->list.alloc);
+	l_item = &cs->list.items[cs->list.nr++];
+	l_item->e = e;
+	l_item->value_index = e->value_list.nr - 1;
+
 	if (cf) {
 		kv_info->filename = strintern(cf->name);
 		kv_info->linenr = cf->linenr;
@@ -1316,6 +1350,9 @@ void git_configset_init(struct config_set *cs)
 {
 	hashmap_init(&cs->config_hash, (hashmap_cmp_fn)config_set_element_cmp, 0);
 	cs->hash_initialized = 1;
+	cs->list.nr = 0;
+	cs->list.alloc = 0;
+	cs->list.items = NULL;
 }
 
 void git_configset_clear(struct config_set *cs)
@@ -1332,6 +1369,10 @@ void git_configset_clear(struct config_set *cs)
 	}
 	hashmap_free(&cs->config_hash, 1);
 	cs->hash_initialized = 0;
+	free(cs->list.items);
+	cs->list.nr = 0;
+	cs->list.alloc = 0;
+	cs->list.items = NULL;
 }
 
 static int config_set_callback(const char *key, const char *value, void *cb)
@@ -1450,7 +1491,7 @@ static void git_config_check_init(void)
 	if (the_config_set.hash_initialized)
 		return;
 	git_configset_init(&the_config_set);
-	git_config(config_set_callback, &the_config_set);
+	git_config_raw(config_set_callback, &the_config_set);
 }
 
 void git_config_clear(void)
diff --git a/t/t4055-diff-context.sh b/t/t4055-diff-context.sh
index cd04543..741e080 100755
--- a/t/t4055-diff-context.sh
+++ b/t/t4055-diff-context.sh
@@ -79,7 +79,7 @@ test_expect_success 'non-integer config parsing' '
 test_expect_success 'negative integer config parsing' '
 	git config diff.context -1 &&
 	test_must_fail git diff 2>output &&
-	test_i18ngrep "bad config file" output
+	test_i18ngrep "bad config variable" output
 '
 
 test_expect_success '-U0 is valid, so is diff.context=0' '
-- 
1.9.0.GIT

Re: [PATCH v5 4/7] rewrite git_config() to use the config-set API

[Matthieu Moy]

Tanay Abhra <tanayabh@gmail.com> writes:

> +			if (!kv_info->linenr)
> +				die("unable to parse '%s' from command-line config", entry->key);
> +			else
> +				die("bad config variable '%s' at file line %d in %s",

Also two missing _("...") here.

Note that there are missing _("...") in config.c before your patch too.
I'll send a patch to fix this regardless of your series.

-- 
Matthieu Moy
http://www-verimag.imag.fr/~moy/

[PATCH v5 5/7] add a test for semantic errors in config files

[Tanay Abhra]

Semantic errors (for example, for alias.* variables NULL values are
not allowed) in configuration files cause a die printing the line
number and file name of the offending value.

Add a test documenting that such errors cause a die printing the
accurate line number and file name.

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
---
 t/t1308-config-set.sh | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/t/t1308-config-set.sh b/t/t1308-config-set.sh
index 7fdf840..e2f9d0b 100755
--- a/t/t1308-config-set.sh
+++ b/t/t1308-config-set.sh
@@ -197,4 +197,15 @@ test_expect_success 'proper error on error in custom config files' '
 	test_cmp expect actual
 '
 
+test_expect_success 'check line errors for malformed values' '
+	mv .git/config .git/config.old &&
+	test_when_finished "mv .git/config.old .git/config" &&
+	cat >.git/config <<-\EOF &&
+	[alias]
+		br
+	EOF
+	test_expect_code 128 git br 2>result &&
+	grep "fatal: bad config variable '\''alias.br'\'' at file line 2 in .git/config" result
+'
+
 test_done
-- 
1.9.0.GIT

[PATCH 6/7] config: add `git_die_config()` to the config-set API

[Tanay Abhra]

Add `git_die_config` that dies printing the line number and the file name
of the highest priority value for the configuration variable `key`.

It has usage in non-callback based config value retrieval where we can
raise an error and die if there is a semantic error.
For example,

	if (!git_config_get_value(key, &value)) {
		/* NULL values not allowed */
		if (!value)
			git_config_die(key);
		else
			/* do work */
	}

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
---
 Documentation/technical/api-config.txt |  5 +++++
 cache.h                                |  1 +
 config.c                               | 27 +++++++++++++++++++++++++--
 3 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/Documentation/technical/api-config.txt b/Documentation/technical/api-config.txt
index 815c1ee..e7ec7cc 100644
--- a/Documentation/technical/api-config.txt
+++ b/Documentation/technical/api-config.txt
@@ -155,6 +155,11 @@ as well as retrieval for the queried variable, including:
 	Similar to `git_config_get_string`, but expands `~` or `~user` into
 	the user's home directory when found at the beginning of the path.
 
+`void git_die_config(const char *key)`::
+
+	Dies printing the line number and the file name of the highest
+	priority value for the configuration variable `key`.
+
 See test-config.c for usage examples.
 
 Value Parsing Helpers
diff --git a/cache.h b/cache.h
index 4d3c6bd..243f618 100644
--- a/cache.h
+++ b/cache.h
@@ -1406,6 +1406,7 @@ extern int git_config_get_bool(const char *key, int *dest);
 extern int git_config_get_bool_or_int(const char *key, int *is_bool, int *dest);
 extern int git_config_get_maybe_bool(const char *key, int *dest);
 extern int git_config_get_pathname(const char *key, const char **dest);
+extern void git_die_config(const char *key);
 
 extern int committer_ident_sufficiently_given(void);
 extern int author_ident_sufficiently_given(void);
diff --git a/config.c b/config.c
index 4937515..03369b8 100644
--- a/config.c
+++ b/config.c
@@ -1515,8 +1515,12 @@ const struct string_list *git_config_get_value_multi(const char *key)
 
 int git_config_get_string_const(const char *key, const char **dest)
 {
+	int ret;
 	git_config_check_init();
-	return git_configset_get_string_const(&the_config_set, key, dest);
+	ret = git_configset_get_string_const(&the_config_set, key, dest);
+	if (ret < 0)
+		git_die_config(key);
+	return ret;
 }
 
 int git_config_get_string(const char *key, char **dest)
@@ -1557,10 +1561,29 @@ int git_config_get_maybe_bool(const char *key, int *dest)
 
 int git_config_get_pathname(const char *key, const char **dest)
 {
+	int ret;
 	git_config_check_init();
-	return git_configset_get_pathname(&the_config_set, key, dest);
+	ret = git_configset_get_pathname(&the_config_set, key, dest);
+	if (ret < 0)
+		git_die_config(key);
+	return ret;
 }
 
+void git_die_config(const char *key)
+{
+	const struct string_list *values;
+	struct key_value_info *kv_info;
+	values = git_config_get_value_multi(key);
+	kv_info = values->items[values->nr - 1].util;
+	if (!kv_info->linenr)
+		die("unable to parse '%s' from command-line config", key);
+	else
+		die("bad config variable '%s' at file line %d in %s",
+			key,
+			kv_info->linenr,
+			kv_info->filename);
+ }
+
 /*
  * Find all the stuff for git_config_set() below.
  */
-- 
1.9.0.GIT

Re: [PATCH 6/7] config: add `git_die_config()` to the config-set API

[Matthieu Moy]

Tanay Abhra <tanayabh@gmail.com> writes:

> +	if (!kv_info->linenr)
> +		die("unable to parse '%s' from command-line config", key);
> +	else
> +		die("bad config variable '%s' at file line %d in %s",

And two more missing _(...).

-- 
Matthieu Moy
http://www-verimag.imag.fr/~moy/

[PATCH 7/7] add tests for `git_config_get_string_const()`

[Tanay Abhra]

Add tests for `git_config_get_string_const()`, check whether it
dies printing the line number and the file name if a NULL
value is retrieved for the given key.

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
---
 t/t1308-config-set.sh | 10 ++++++++++
 test-config.c         | 10 ++++++++++
 2 files changed, 20 insertions(+)

diff --git a/t/t1308-config-set.sh b/t/t1308-config-set.sh
index e2f9d0b..f012dd6 100755
--- a/t/t1308-config-set.sh
+++ b/t/t1308-config-set.sh
@@ -119,6 +119,16 @@ test_expect_success 'find integer value for a key' '
 	check_config get_int lamb.chop 65
 '
 
+test_expect_success 'find string value for a key' '
+	check_config get_string case.baz hask &&
+	check_config expect_code 1 get_string case.ba "Value not found for \"case.ba\""
+'
+
+test_expect_success 'check line error when NULL string is queried' '
+	test_expect_code 128 test-config get_string case.foo 2>result &&
+	grep "fatal: bad config variable '\''case.foo'\'' at file line 7 in .git/config" result
+'
+
 test_expect_success 'find integer if value is non parse-able' '
 	check_config expect_code 128 get_int lamb.head
 '
diff --git a/test-config.c b/test-config.c
index 9dd1b22..6a77552 100644
--- a/test-config.c
+++ b/test-config.c
@@ -16,6 +16,8 @@
  *
  * get_bool -> print bool value for the entered key or die
  *
+ * get_string -> print string value for the entered key or die
+ *
  * configset_get_value -> returns value with the highest priority for the entered key
  * 			from a config_set constructed from files entered as arguments.
  *
@@ -84,6 +86,14 @@ int main(int argc, char **argv)
 			printf("Value not found for \"%s\"\n", argv[2]);
 			goto exit1;
 		}
+	} else if (argc == 3 && !strcmp(argv[1], "get_string")) {
+		if (!git_config_get_string_const(argv[2], &v)) {
+			printf("%s\n", v);
+			goto exit0;
+		} else {
+			printf("Value not found for \"%s\"\n", argv[2]);
+			goto exit1;
+		}
 	} else if (!strcmp(argv[1], "configset_get_value")) {
 		for (i = 3; i < argc; i++) {
 			int err;
-- 
1.9.0.GIT