introduced defines for error codes

include/libpsl.h

@@ -38,6 +38,14 @@
 extern "C" {
 #endif
 
+typedef enum {
+	PSL_SUCCESS = 0,
+	PSL_ERR_INVALID_ARG = -1,
+	PSL_ERR_CONVERTER = -2, /* failed to open libicu utf-16 converter */
+	PSL_ERR_TO_UTF16 = -3, /* failed to convert to utf-16 */
+	PSL_ERR_TO_LOWER = -4, /* failed to convert utf-16 to lowercase */
+	PSL_ERR_TO_UTF8 = -5 /* failed to convert utf-16 to utf-8 */
+} psl_error_t;
 
 typedef struct _psl_ctx_st psl_ctx_t;
 

src/psl.c

@@ -852,24 +852,25 @@ int psl_is_cookie_domain_acceptable(const psl_ctx_t *psl, const char *hostname,
  * @lower is %NULL on error.
  * The return value 'lower' must be freed after usage.
  *
- * Returns: 0 on success, negative value on error.
+ * Returns: psl_error_t value.
- *   -1 @str is a %NULL value
+ *   PSL_SUCCESS: Success
- *   -2 failed to open converter with name @encoding
+ *   PSL_ERR_INVALID_ARG: @str is a %NULL value.
- *   -3 failed to convert @str to unicode
+ *   PSL_ERR_CONVERTER: Failed to open the unicode converter with name @encoding
- *   -4 failed to convert unicode to lowercase
+ *   PSL_ERR_TO_UTF16: Failed to convert @str to unicode
- *   -5 failed to convert unicode to UTF-8
+ *   PSL_ERR_TO_LOWER: Failed to convert unicode to lowercase
+ *   PSL_ERR_TO_UTF8: Failed to convert unicode to UTF-8
  *
  * Since: 0.4
  */
-int psl_str_to_utf8lower(const char *str, const char *encoding, const char *locale, char **lower)
+psl_error_t psl_str_to_utf8lower(const char *str, const char *encoding, const char *locale, char **lower)
 {
-	int ret = -1;
+	int ret = PSL_ERR_INVALID_ARG;
 
 	if (lower)
 		*lower = NULL;
 
 	if (!str)
-		return -1;
+		return PSL_ERR_INVALID_ARG;
 
 	/* shortcut to avoid costly conversion */
 	if (_str_is_ascii(str)) {
@@ -883,7 +884,7 @@ int psl_str_to_utf8lower(const char *str, const char *encoding, const char *loca
 				if (isupper(*p))
 					*p = tolower(*p);
 		}
-		return 0;
+		return PSL_SUCCESS;
 	}
 
 #ifdef WITH_LIBICU
@@ -912,21 +913,21 @@ int psl_str_to_utf8lower(const char *str, const char *encoding, const char *loca
 				if (U_SUCCESS(status)) {
 					if (lower)
 						*lower = strdup(utf8_lower);
-					ret = 0;
+					ret = PSL_SUCCESS;
 				} else {
-					ret = -5;
+					ret = PSL_ERR_TO_UTF8;
 					/* fprintf(stderr, "Failed to convert UTF-16 to UTF-8 (status %d)\n", status); */
 				}
 			} else {
-				ret = -4;
+				ret = PSL_ERR_TO_LOWER;
 				/* fprintf(stderr, "Failed to convert UTF-16 to lowercase (status %d)\n", status); */
 			}
 		} else {
-			ret = -3;
+			ret = PSL_ERR_TO_UTF16;
 			/* fprintf(stderr, "Failed to convert string to UTF-16 (status %d)\n", status); */
 		}
 	} else {
-		ret = -2;
+		ret = PSL_ERR_CONVERTER;
 		/* fprintf(stderr, "Failed to open converter for '%s' (status %d)\n", encoding, status); */
 	}
 	} while (0);

tests/test-registrable-domain.c

@@ -55,7 +55,7 @@ static void test(const psl_ctx_t *psl, const char *domain, const char *expected_
 	char *lower;
 
 	/* our test data is fixed to UTF-8 (english), so provide it here */
-	if (psl_str_to_utf8lower(domain, "utf-8", "en", &lower) == 0)
+	if (psl_str_to_utf8lower(domain, "utf-8", "en", &lower) == PSL_SUCCESS)
 		domain = lower;
 
 	result = psl_registrable_domain(psl, domain);

tools/psl.c

@@ -149,7 +149,7 @@ int main(int argc, const char *const *argv)
 		if (arg >= argv + argc) {
 			char buf[256], *domain, *lower;
 			size_t len;
-			int rc;
+			psl_error_t rc;
 
 			/* read URLs from STDIN */
 			while (fgets(buf, sizeof(buf), stdin)) {
@@ -158,7 +158,7 @@ int main(int argc, const char *const *argv)
 				for (len = strlen(domain); len && isspace(domain[len - 1]); len--); /* skip trailing spaces */
 				domain[len] = 0;
 
-				if ((rc = psl_str_to_utf8lower(domain, NULL, NULL, &lower)) != 0)
+				if ((rc = psl_str_to_utf8lower(domain, NULL, NULL, &lower)) != PSL_SUCCESS)
 					fprintf(stderr, "%s: Failed to convert to lowercase UTF-8 (%d)\n", domain, rc);
 				else if (mode == 1)
 					printf("%s: %d (%s)\n", domain, psl_is_public_suffix(psl, lower), lower);
@@ -169,7 +169,7 @@ int main(int argc, const char *const *argv)
 				else if (mode == 4) {
 					char *cookie_domain_lower;
 
-					if ((rc = psl_str_to_utf8lower(domain, NULL, NULL, &cookie_domain_lower)) != 0)
+					if ((rc = psl_str_to_utf8lower(domain, NULL, NULL, &cookie_domain_lower)) != PSL_SUCCESS)
 						fprintf(stderr, "%s: Failed to convert cookie domain '%s' to lowercase UTF-8 (%d)\n", domain, cookie_domain, rc);
 					else
 						printf("%s: %d\n", domain, psl_is_cookie_domain_acceptable(psl, lower, cookie_domain));