win32: add a case-insensitive version of is_suffixed_with()

3 files changed, 30 insertions, 2 deletions

diff --git a/include/mingw.h b/include/mingw.h
index b8c0b12b5..a1869227d 100644
--- a/include/mingw.h
+++ b/include/mingw.h
@@ -448,6 +448,7 @@ int kill_SIGTERM_by_handle(HANDLE process, int exit_code);
 #define find_mount_point(n, s) find_mount_point(n)
 
 char *is_prefixed_with_case(const char *string, const char *key) FAST_FUNC;
+char *is_suffixed_with_case(const char *string, const char *key) FAST_FUNC;
 void qsort_string_vector_case(char **sv, unsigned count) FAST_FUNC;
 
 /*
diff --git a/libbb/compare_string_array.c b/libbb/compare_string_array.c
index 7ccdaef8a..856739c41 100644
--- a/libbb/compare_string_array.c
+++ b/libbb/compare_string_array.c
@@ -45,6 +45,7 @@ char* FAST_FUNC is_prefixed_with_case(const char *string, const char *key)
  * beginning of prefix key in string. If key is an empty string return pointer
  * to the end of string.
  */
+#if !ENABLE_PLATFORM_MINGW32
 char* FAST_FUNC is_suffixed_with(const char *string, const char *key)
 {
         size_t key_len = strlen(key);
@@ -59,6 +60,33 @@ char* FAST_FUNC is_suffixed_with(const char *string, const char *key)
 
         return NULL;
 }
+#else
+static char* FAST_FUNC is_suffixed(const char *string, const char *key,
+                int (*fn)(const char *, const char*))
+{
+        size_t key_len = strlen(key);
+        ssize_t len_diff = strlen(string) - key_len;
+
+        if (len_diff >= 0) {
+                string += len_diff;
+                if (fn(string, key) == 0) {
+                        return (char*)string;
+                }
+        }
+
+        return NULL;
+}
+
+char* FAST_FUNC is_suffixed_with(const char *string, const char *key)
+{
+        return is_suffixed(string, key, strcmp);
+}
+
+char* FAST_FUNC is_suffixed_with_case(const char *string, const char *key)
+{
+        return is_suffixed(string, key, strcasecmp);
+}
+#endif
 
 /* returns the array index of the string */
 /* (index of first match is returned, or -1) */
diff --git a/win32/mingw.c b/win32/mingw.c
index 10169266d..162fae45b 100644
--- a/win32/mingw.c
+++ b/win32/mingw.c
@@ -332,8 +332,7 @@ static int has_exec_format(const char *name)
         unsigned char buf[1024];
 
         /* special case: skip DLLs, there are thousands of them! */
-        n = strlen(name);
-        if (n > 4 && !strcasecmp(name+n-4, ".dll"))
+        if (is_suffixed_with_case(name, ".dll"))
                 return 0;
 
         n = open_read_close(name, buf, sizeof(buf));