[PATCH v6 2/6] Add git_env_ulong() to parse environment variable

[Steffen Prohaska <prohaska@zib.de>]

The new function will be used to parse GIT_MMAP_LIMIT and
GIT_ALLOC_LIMIT.

Signed-off-by: Steffen Prohaska <prohaska@zib.de>
---
 cache.h  |  1 +
 config.c | 11 +++++++++++
 2 files changed, 12 insertions(+)

diff --git a/cache.h b/cache.h
index fcb511d..b820b6a 100644
--- a/cache.h
+++ b/cache.h
@@ -1318,6 +1318,7 @@ extern int git_config_rename_section_in_file(const char *, const char *, const c
 extern const char *git_etc_gitconfig(void);
 extern int check_repository_format_version(const char *var, const char *value, void *cb);
 extern int git_env_bool(const char *, int);
+extern unsigned long git_env_ulong(const char *, unsigned long);
 extern int git_config_system(void);
 extern int config_error_nonbool(const char *);
 #if defined(__GNUC__)
diff --git a/config.c b/config.c
index 058505c..178721f 100644
--- a/config.c
+++ b/config.c
@@ -1122,6 +1122,17 @@ int git_env_bool(const char *k, int def)
 	return v ? git_config_bool(k, v) : def;
 }
 
+/*
+ * Use default if environment variable is unset or empty string.
+ */
+unsigned long git_env_ulong(const char *k, unsigned long val)
+{
+	const char *v = getenv(k);
+	if (v && *v && !git_parse_ulong(v, &val))
+		die("failed to parse %s", k);
+	return val;
+}
+
 int git_config_system(void)
 {
 	return !git_env_bool("GIT_CONFIG_NOSYSTEM", 0);
-- 
2.1.0.8.gf3a29c8