[PATCH 15/25] config: add git_config_get_timestamp()

["Derrick Stolee via GitGitGadget" <gitgitgadget@gmail.com>]

From: Derrick Stolee <derrickstolee@github.com>

The existing config parsing methods do not include a way to consistently
parse timestamps across all platforms. Recall that "unsigned long" is
32 bits on 64-bit Windows, so git_config_get_ulong() is insufficient.

Adding a new type requires quite a bit of boilerplate to match the style
of other types.

RFC-QUESTION: Would this be better to use uintmax_t, which could be cast
to timestamp_t or other types more robust than "unsigned long"?

Signed-off-by: Derrick Stolee <derrickstolee@github.com>
---
 config.c | 39 +++++++++++++++++++++++++++++++++++++++
 config.h | 14 ++++++++++++++
 2 files changed, 53 insertions(+)

diff --git a/config.c b/config.c
index e0c03d154c9..84021b7d504 100644
--- a/config.c
+++ b/config.c
@@ -1228,6 +1228,15 @@ int git_parse_ulong(const char *value, unsigned long *ret)
 	return 1;
 }
 
+int git_parse_timestamp(const char *value, timestamp_t *ret)
+{
+	uintmax_t tmp;
+	if (!git_parse_unsigned(value, &tmp, maximum_unsigned_value_of_type(timestamp_t)))
+		return 0;
+	*ret = tmp;
+	return 1;
+}
+
 int git_parse_ssize_t(const char *value, ssize_t *ret)
 {
 	intmax_t tmp;
@@ -1296,6 +1305,14 @@ unsigned long git_config_ulong(const char *name, const char *value)
 	return ret;
 }
 
+timestamp_t git_config_timestamp(const char *name, const char *value)
+{
+	timestamp_t ret;
+	if (!git_parse_timestamp(value, &ret))
+		die_bad_number(name, value);
+	return ret;
+}
+
 ssize_t git_config_ssize_t(const char *name, const char *value)
 {
 	ssize_t ret;
@@ -2328,6 +2345,16 @@ int git_configset_get_ulong(struct config_set *cs, const char *key, unsigned lon
 		return 1;
 }
 
+int git_configset_get_timestamp(struct config_set *cs, const char *key, timestamp_t *dest)
+{
+	const char *value;
+	if (!git_configset_get_value(cs, key, &value)) {
+		*dest = git_config_timestamp(key, value);
+		return 0;
+	} else
+		return 1;
+}
+
 int git_configset_get_bool(struct config_set *cs, const char *key, int *dest)
 {
 	const char *value;
@@ -2471,6 +2498,13 @@ int repo_config_get_ulong(struct repository *repo,
 	return git_configset_get_ulong(repo->config, key, dest);
 }
 
+int repo_config_get_timestamp(struct repository *repo,
+			      const char *key, timestamp_t *dest)
+{
+	git_config_check_init(repo);
+	return git_configset_get_timestamp(repo->config, key, dest);
+}
+
 int repo_config_get_bool(struct repository *repo,
 			 const char *key, int *dest)
 {
@@ -2544,6 +2578,11 @@ int git_config_get_ulong(const char *key, unsigned long *dest)
 	return repo_config_get_ulong(the_repository, key, dest);
 }
 
+int git_config_get_timestamp(const char *key, timestamp_t *dest)
+{
+	return repo_config_get_timestamp(the_repository, key, dest);
+}
+
 int git_config_get_bool(const char *key, int *dest)
 {
 	return repo_config_get_bool(the_repository, key, dest);
diff --git a/config.h b/config.h
index ab0106d2875..a6e4d35da0a 100644
--- a/config.h
+++ b/config.h
@@ -206,6 +206,7 @@ int config_with_options(config_fn_t fn, void *,
 
 int git_parse_ssize_t(const char *, ssize_t *);
 int git_parse_ulong(const char *, unsigned long *);
+int git_parse_timestamp(const char *, timestamp_t *);
 
 /**
  * Same as `git_config_bool`, except that it returns -1 on error rather
@@ -226,6 +227,11 @@ int64_t git_config_int64(const char *, const char *);
  */
 unsigned long git_config_ulong(const char *, const char *);
 
+/**
+ * Identical to `git_config_int`, but for (unsigned) timestamps.
+ */
+timestamp_t git_config_timestamp(const char *name, const char *value);
+
 ssize_t git_config_ssize_t(const char *, const char *);
 
 /**
@@ -469,6 +475,7 @@ int git_configset_get_string(struct config_set *cs, const char *key, char **dest
 int git_configset_get_string_tmp(struct config_set *cs, const char *key, const char **dest);
 int git_configset_get_int(struct config_set *cs, const char *key, int *dest);
 int git_configset_get_ulong(struct config_set *cs, const char *key, unsigned long *dest);
+int git_configset_get_timestamp(struct config_set *cs, const char *key, timestamp_t *dest);
 int git_configset_get_bool(struct config_set *cs, const char *key, int *dest);
 int git_configset_get_bool_or_int(struct config_set *cs, const char *key, int *is_bool, int *dest);
 int git_configset_get_maybe_bool(struct config_set *cs, const char *key, int *dest);
@@ -489,6 +496,8 @@ int repo_config_get_int(struct repository *repo,
 			const char *key, int *dest);
 int repo_config_get_ulong(struct repository *repo,
 			  const char *key, unsigned long *dest);
+int repo_config_get_timestamp(struct repository *repo,
+			      const char *key, timestamp_t *dest);
 int repo_config_get_bool(struct repository *repo,
 			 const char *key, int *dest);
 int repo_config_get_bool_or_int(struct repository *repo,
@@ -558,6 +567,11 @@ int git_config_get_int(const char *key, int *dest);
  */
 int git_config_get_ulong(const char *key, unsigned long *dest);
 
+/**
+ * Similar to `git_config_get_int` but for (unsigned) timestamps.
+ */
+int git_config_get_timestamp(const char *key, timestamp_t *dest);
+
 /**
  * Finds and parses the value into a boolean value, for the configuration
  * variable `key` respecting keywords like "true" and "false". Integer
-- 
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