From: Michael Tremer <michael.tremer@ipfire.org>
Date: Fri, 19 Aug 2022 10:25:43 +0000 (+0000)
Subject: string: Add function that parses bytes
X-Git-Tag: 0.9.28~439
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=528b1f1c3d0d80b26334e33ce1cfae77dfd0d689;p=pakfire.git

string: Add function that parses bytes

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>
---

diff --git a/src/libpakfire/include/pakfire/string.h b/src/libpakfire/include/pakfire/string.h
index 510217ba2..a0e46d9c6 100644
--- a/src/libpakfire/include/pakfire/string.h
+++ b/src/libpakfire/include/pakfire/string.h
@@ -64,6 +64,8 @@ int __pakfire_strftime(char* buffer, const size_t length,
 int __pakfire_strftime_now(char* buffer, const size_t length, const char* format)
 	__attribute__((format(strftime, 3, 0)));
 
+size_t pakfire_string_parse_bytes(const char* s);
+
 #endif
 
 #endif /* PAKFIRE_STRING_H */
diff --git a/src/libpakfire/string.c b/src/libpakfire/string.c
index 527a079ae..bd0b07642 100644
--- a/src/libpakfire/string.c
+++ b/src/libpakfire/string.c
@@ -370,3 +370,33 @@ int __pakfire_strftime_now(char* buffer, size_t length, const char* format) {
 
 	return __pakfire_strftime(buffer, length, format, t);
 }
+
+size_t pakfire_string_parse_bytes(const char* s) {
+	const char* units = "kMGT";
+	char* unit = NULL;
+
+	// Read the numeric value
+	size_t bytes = strtoul(s, &unit, 10);
+
+	// Return bytes if there is no unit
+	if (!unit || !*unit)
+		return bytes;
+
+	// Is the unit of the correct length?
+	const size_t length = strlen(unit);
+	if (length > 1)
+		goto ERROR;
+
+	// Walk through all units and find a match
+	for (const char* u = units; *u; u++) {
+		bytes *= 1024;
+
+		// End if the unit matches
+		if (*unit == *u)
+			return bytes;
+	}
+
+ERROR:
+	errno = EINVAL;
+	return 0;
+}
diff --git a/tests/libpakfire/string.c b/tests/libpakfire/string.c
index c2408b91d..cfc021402 100644
--- a/tests/libpakfire/string.c
+++ b/tests/libpakfire/string.c
@@ -290,6 +290,34 @@ FAIL:
 	return EXIT_FAILURE;
 }
 
+static int test_parse_bytes(const struct test* t) {
+	// Zero without unit
+	ASSERT(pakfire_string_parse_bytes("0") == (size_t)0);
+
+	// Zero with valid units
+	ASSERT(pakfire_string_parse_bytes("0k") == (size_t)0);
+	ASSERT(pakfire_string_parse_bytes("0M") == (size_t)0);
+	ASSERT(pakfire_string_parse_bytes("0G") == (size_t)0);
+	ASSERT(pakfire_string_parse_bytes("0T") == (size_t)0);
+
+	// Zero with invalid units
+	ASSERT_ERRNO(pakfire_string_parse_bytes("0X")  == (size_t)0, EINVAL);
+	ASSERT_ERRNO(pakfire_string_parse_bytes("0XX") == (size_t)0, EINVAL);
+	ASSERT_ERRNO(pakfire_string_parse_bytes("0MM") == (size_t)0, EINVAL);
+
+	// One with valid units
+	ASSERT(pakfire_string_parse_bytes("1")  == (size_t)1);
+	ASSERT(pakfire_string_parse_bytes("1k") == (size_t)1024);
+	ASSERT(pakfire_string_parse_bytes("1M") == (size_t)1024 * 1024);
+	ASSERT(pakfire_string_parse_bytes("1G") == (size_t)1024 * 1024 * 1024);
+	ASSERT(pakfire_string_parse_bytes("1T") == (size_t)1024 * 1024 * 1024 * 1024);
+
+	return EXIT_SUCCESS;
+
+FAIL:
+	return EXIT_FAILURE;
+}
+
 int main(int argc, const char* argv[]) {
 	testsuite_add_test(test_string_set);
 	testsuite_add_test(test_string_startswith);
@@ -300,6 +328,7 @@ int main(int argc, const char* argv[]) {
 	testsuite_add_test(test_string_split);
 	testsuite_add_test(test_string_join);
 	testsuite_add_test(test_format_size);
+	testsuite_add_test(test_parse_bytes);
 
 	return testsuite_run(argc, argv);
 }