Commit 1196de4f263bdbb02c2c5b7030f159c2ff23af34
2021-08-31T15:22:44
util: introduce `git__strlcmp` Introduce a utility function that compares a NUL terminated string to a possibly not-NUL terminated string with length. This is similar to `strncmp` but with an added check to ensure that the lengths match (not just the `size` portion of the two strings).
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diff --git a/src/util.h b/src/util.h
index a773536..68c2b18 100644
--- a/src/util.h
+++ b/src/util.h
@@ -168,6 +168,17 @@ extern int git__strncasecmp(const char *a, const char *b, size_t sz);
extern int git__strcasesort_cmp(const char *a, const char *b);
+/*
+ * Compare some NUL-terminated `a` to a possibly non-NUL terminated
+ * `b` of length `b_len`; like `strncmp` but ensuring that
+ * `strlen(a) == b_len` as well.
+ */
+GIT_INLINE(int) git__strlcmp(const char *a, const char *b, size_t b_len)
+{
+ int cmp = strncmp(a, b, b_len);
+ return cmp ? cmp : (int)a[b_len];
+}
+
typedef struct {
git_atomic32 refcount;
void *owner;
diff --git a/tests/core/string.c b/tests/core/string.c
index 85db0c6..928dfbc 100644
--- a/tests/core/string.c
+++ b/tests/core/string.c
@@ -123,3 +123,14 @@ void test_core_string__strcasecmp(void)
cl_assert(git__strcasecmp("et", "e\342\202\254ghi=") < 0);
cl_assert(git__strcasecmp("\303\215", "\303\255") < 0);
}
+
+void test_core_string__strlcmp(void)
+{
+ const char foo[3] = { 'f', 'o', 'o' };
+
+ cl_assert(git__strlcmp("foo", "foo", 3) == 0);
+ cl_assert(git__strlcmp("foo", foo, 3) == 0);
+ cl_assert(git__strlcmp("foo", "foobar", 3) == 0);
+ cl_assert(git__strlcmp("foobar", "foo", 3) > 0);
+ cl_assert(git__strlcmp("foo", "foobar", 6) < 0);
+}