add strchrnul

Author: ZERICO2005

src/libc/include/string.h

@@ -65,6 +65,9 @@ char *strchr(const char *s, int c)
 char *strrchr(const char *s, int c)
     __attribute__((nonnull(1)));
 
+char *strchrnul(const char *s, int c)
+    __NOEXCEPT __attribute__((nonnull(1))) __attribute__((__pure__));
+
 char *strpbrk(const char *s, const char *accept)
     __attribute__((nonnull(1, 2)));
 

src/libc/strchrnul.src

@@ -0,0 +1,25 @@
+	assume	adl=1
+
+	section	.text
+
+	public	_strchrnul
+
+_strchrnul:
+	pop	bc, hl, de
+	push	de, hl, bc
+	xor	a, a
+	ld	bc, 0
+	push	hl
+	cpir
+	sbc	hl, hl
+	sbc	hl, bc
+	ex	(sp), hl
+	pop	bc
+	ld	a, e
+	; HL = str
+	; BC = strlen(str) + 1
+	; A = ch
+	cpir
+	dec	hl
+	; points to the '\0' if ch was not found
+	ret

test/standalone/asprintf_fprintf/src/main.c

@@ -74,6 +74,9 @@ int T_strcmp(const char *s1, const char *s2)
 int T_strncmp(const char *s1, const char *s2, size_t n)
     __attribute__((nonnull(1, 2)));
 
+char *T_strchrnul(const char *s, int c)
+    __attribute__((nonnull(1)));
+
 void T_bzero(void* s, size_t n);
 
 #else
@@ -92,6 +95,7 @@ void T_bzero(void* s, size_t n);
 #define T_strlen strlen
 #define T_strcmp strcmp
 #define T_strncmp strncmp
+#define T_strchrnul strchrnul
 #define T_bzero bzero
 
 #endif
@@ -778,6 +782,17 @@ int memmem_test(void) {
     return 0;
 }
 
+int strchrnul_test(void) {
+    C(T_strchrnul(SINK, '\0') == SINK);
+    C(T_strchrnul(SINK, '\xff') == SINK);
+    const size_t test_3_len = strlen(test_3);
+    C(T_strchrnul(test_3, '\0') == test_3 + test_3_len);
+    for (size_t i = 0; i < test_3_len; i++) {
+        C(T_strchrnul(test_3, test_3[i]) == strchr(test_3, test_3[i]));
+    }
+    return 0;
+}
+
 int run_tests(void) {
     int ret = 0;
     /* boot_asprintf */
@@ -807,6 +822,7 @@ int run_tests(void) {
     TEST(strlcat_test());
     TEST(stpncpy_test());
     TEST(memmem_test());
+    TEST(strchrnul_test());
 
     return 0;
 }

test/standalone/asprintf_fprintf/src/rename.asm

@@ -3,7 +3,7 @@
 	section	.text
 
 	public	_T_memset, _T_memcpy, _T_memmove, _T_memcmp, _T_memccpy, _T_mempcpy, _T_memrchr, _T_memmem
-	public	_T_strlen, _T_strcmp, _T_strncmp, _T_stpcpy, _T_stpncpy, _T_strlcat
+	public	_T_strlen, _T_strcmp, _T_strncmp, _T_stpcpy, _T_stpncpy, _T_strlcat, _T_strchrnul
 	public	_T_bzero
 
 _T_memset := _memset
@@ -21,6 +21,7 @@ _T_strncmp := _strncmp
 _T_stpcpy := _stpcpy
 _T_stpncpy := _stpncpy
 _T_strlcat := _strlcat
+_T_strchrnul := _strchrnul
 
 _T_bzero := _bzero
 
@@ -31,5 +32,5 @@ _NULL_ptr:
 	db	$00, $00, $00
 
 	extern	_memset, _memcpy, _memmove, _memcmp, _memccpy, _mempcpy, _memrchr, _memmem
-	extern	_strlen, _strcmp, _strncmp, _stpcpy, _stpncpy, _strlcat
+	extern	_strlen, _strcmp, _strncmp, _stpcpy, _stpncpy, _strlcat, _strchrnul
 	extern	_bzero