treewide: Move skip_atoi function to commonlib

BUG=none
TEST=Build and verify on Screebo
TEST=make unit-tests

```
$ make tests/commonlib/bsd/string-test
[==========] tests_commonlib_bsd_string-test(tests): Running 1 test(s).
[ RUN      ] test_skip_atoi
[       OK ] test_skip_atoi
[==========] tests_commonlib_bsd_string-test(tests): 1 test(s) run.
[  PASSED  ] 1 test(s).
```

Change-Id: Ifaaa80d0c696a625592ce301f9e3eefb2b4dcd98
Signed-off-by: Maximilian Brune <maximilian.brune@9elements.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/82910
Reviewed-by: Jakub Czapiga <czapiga@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Subrata Banik <subratabanik@google.com>

payloads/libpayload/include/string.h

@@ -29,6 +29,7 @@
 #ifndef _STRING_H
 #define _STRING_H
 
+#include <commonlib/bsd/string.h>
 #include <stddef.h>
 
 /**

payloads/libpayload/libc/Makefile.mk

@@ -47,6 +47,7 @@ ifeq ($(CONFIG_LP_LIBC),y)
 libc-srcs += $(coreboottop)/src/commonlib/bsd/elog.c
 libc-srcs += $(coreboottop)/src/commonlib/bsd/gcd.c
 libc-srcs += $(coreboottop)/src/commonlib/bsd/ipchksum.c
+libc-srcs += $(coreboottop)/src/commonlib/bsd/string.c
 ifeq ($(CONFIG_LP_GPL),y)
 libc-srcs += $(coreboottop)/src/commonlib/list.c
 endif

src/commonlib/Makefile.mk

@@ -65,3 +65,7 @@ decompressor-y += bsd/gcd.c
 all-y += bsd/gcd.c
 
 all-y += bsd/ipchksum.c
+
+decompressor-y += bsd/string.c
+smm-y += bsd/string.c
+all-y += bsd/string.c

src/commonlib/bsd/include/commonlib/bsd/string.h

@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#ifndef _COMMONLIB_BSD_STRING_H_
+#define _COMMONLIB_BSD_STRING_H_
+
+#include <stdint.h>
+
+unsigned int skip_atoi(char **ptr);
+
+#endif  /* _COMMONLIB_BSD_STRING_H_ */

src/commonlib/bsd/string.c

@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: BSD-3-Clause */
+
+#include <commonlib/bsd/string.h>
+#include <ctype.h>
+
+unsigned int skip_atoi(char **ptr)
+{
+	unsigned int result = 0;
+	char *str;
+
+	for (str = *ptr; isdigit(str[0]); str++)
+		result = result * 10 + (str[0] - '0');
+	*ptr = str;
+	return result;
+}

src/include/string.h

@@ -3,6 +3,7 @@
 #ifndef STRING_H
 #define STRING_H
 
+#include <commonlib/bsd/string.h>
 #include <stddef.h>
 
 void *memcpy(void *dest, const void *src, size_t n);
@@ -36,11 +37,4 @@ long atol(const char *str);
  */
 char *strrchr(const char *s, int c);
 
-/*
- * Parses an unsigned integer and moves the input pointer forward to the first
- * character that's not a valid digit. s and *s must not be NULL. Result
- * undefined if it overruns the return type size.
- */
-unsigned int skip_atoi(char **s);
-
 #endif /* STRING_H */

src/lib/string.c

@@ -125,15 +125,6 @@ int strncmp(const char *s1, const char *s2, int maxlen)
 	return 0;
 }
 
-unsigned int skip_atoi(char **s)
-{
-	unsigned int i = 0;
-
-	while (isdigit(**s))
-		i = i*10 + *((*s)++) - '0';
-	return i;
-}
-
 int strspn(const char *str, const char *spn)
 {
 	int ret = 0;

tests/commonlib/bsd/Makefile.mk

@@ -3,6 +3,7 @@
 tests-y += helpers-test
 tests-y += gcd-test
 tests-y += ipchksum-test
+tests-y += string-test
 
 helpers-test-srcs += tests/commonlib/bsd/helpers-test.c
 
@@ -11,3 +12,6 @@ gcd-test-srcs += src/commonlib/bsd/gcd.c
 
 ipchksum-test-srcs += tests/commonlib/bsd/ipchksum-test.c
 ipchksum-test-srcs += src/commonlib/bsd/ipchksum.c
+
+string-test-srcs += tests/commonlib/bsd/string-test.c
+string-test-srcs += src/commonlib/bsd/string.c

tests/commonlib/bsd/string-test.c

@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <commonlib/bsd/string.h>
+#include <tests/test.h>
+
+/* Used to test skip_atoi */
+struct str_with_u_val_t {
+	char *str;
+	uint32_t value;
+	uint32_t offset;
+} str_with_u_val[] = {
+	{"42aa", 42, 2},
+	{"a", 0, 0},
+	{"0", 0, 1},
+	{"4a2", 4, 1},
+};
+
+static void test_skip_atoi(void **state)
+{
+	int i;
+	char *ptr, *copy;
+
+	for (i = 0; i < ARRAY_SIZE(str_with_u_val); i++) {
+		ptr = str_with_u_val[i].str;
+		copy = ptr;
+		assert_true(str_with_u_val[i].value == skip_atoi(&ptr));
+		assert_int_equal(str_with_u_val[i].offset, ptr - copy);
+	}
+}
+
+int main(void)
+{
+	const struct CMUnitTest tests[] = {
+		cmocka_unit_test(test_skip_atoi),
+	};
+
+	return cb_run_group_tests(tests, NULL, NULL);
+}

tests/lib/string-test.c

@@ -43,18 +43,6 @@ struct str_with_l_val_t {
 	{"\t\n\r\f\v-42", -42},
 };
 
-/* Used to test skip_atoi */
-struct str_with_u_val_t {
-	char *str;
-	uint32_t value;
-	uint32_t offset;
-} str_with_u_val[] = {
-	{"42aa", 42, 2},
-	{"a", 0, 0},
-	{"0", 0, 1},
-	{"4a2", 4, 1},
-};
-
 static void test_strdup(void **state)
 {
 	char str[] = "Hello coreboot\n";
@@ -204,19 +192,6 @@ static void test_strncmp(void **state)
 	assert_int_equal(0, strncmp(str, str2, str2_len - 1));
 }
 
-static void test_skip_atoi(void **state)
-{
-	int i;
-	char *ptr, *copy;
-
-	for (i = 0; i < ARRAY_SIZE(str_with_u_val); i++) {
-		ptr = str_with_u_val[i].str;
-		copy = ptr;
-		assert_true(str_with_u_val[i].value == skip_atoi(&ptr));
-		assert_int_equal(str_with_u_val[i].offset, ptr - copy);
-	}
-}
-
 static void test_strspn(void **state)
 {
 	char str[] = "4213401234";
@@ -260,7 +235,6 @@ int main(void)
 		cmocka_unit_test(test_strcpy),
 		cmocka_unit_test(test_strcmp),
 		cmocka_unit_test(test_strncmp),
-		cmocka_unit_test(test_skip_atoi),
 		cmocka_unit_test(test_strspn),
 		cmocka_unit_test(test_strcspn),
 		cmocka_unit_test(test_atol),