Merge the basics component into libc-bottom-half. (#199)

We no longer have a need to maintain basics as a separate component.
Folding it into libc-bottom-half eliminates a fair amount of redundancy.

Makefile

@@ -12,21 +12,13 @@ INSTALL_DIR ?= /usr/local
 THREAD_MODEL ?= single
 # yes or no
 BUILD_DLMALLOC ?= yes
-BUILD_LIBC_BOTTOM_HALF ?= yes
 BUILD_LIBC_TOP_HALF ?= yes
 # The directory where we're store intermediate artifacts.
 OBJDIR ?= $(CURDIR)/build
 
 # Check dependencies.
-ifeq ($(BUILD_LIBC_TOP_HALF),yes)
-ifneq ($(BUILD_LIBC_BOTTOM_HALF),yes)
-$(error BUILD_LIBC_TOP_HALF=yes depends on BUILD_LIBC_BOTTOM_HALF=yes)
-endif
-endif
-ifeq ($(BUILD_LIBC_BOTTOM_HALF),yes)
 ifneq ($(BUILD_DLMALLOC),yes)
-$(error BUILD_LIBC_BOTTOM_HALF=yes depends on BUILD_DLMALLOC=yes)
-endif
+$(error build currently depends on BUILD_DLMALLOC=yes)
 endif
 
 # Variables from this point on are not meant to be overridable via the
@@ -39,12 +31,6 @@ MULTIARCH_TRIPLE = wasm32-wasi
 
 # These variables describe the locations of various files and directories in
 # the source tree.
-BASICS_DIR = $(CURDIR)/basics
-BASICS_INC = $(BASICS_DIR)/include
-BASICS_CRT_SOURCES = $(wildcard $(BASICS_DIR)/crt/*.c)
-BASICS_SOURCES = \
-    $(wildcard $(BASICS_DIR)/sources/*.c) \
-    $(wildcard $(BASICS_DIR)/sources/math/*.c)
 DLMALLOC_DIR = $(CURDIR)/dlmalloc
 DLMALLOC_SRC_DIR = $(DLMALLOC_DIR)/src
 DLMALLOC_SOURCES = $(DLMALLOC_SRC_DIR)/dlmalloc.c
@@ -209,25 +195,15 @@ WASM_CFLAGS += --sysroot="$(SYSROOT)"
 # These variables describe the locations of various files and directories in
 # the build tree.
 objs = $(patsubst $(CURDIR)/%.c,$(OBJDIR)/%.o,$(1))
-BASICS_OBJS = $(call objs,$(BASICS_SOURCES))
 DLMALLOC_OBJS = $(call objs,$(DLMALLOC_SOURCES))
 LIBC_BOTTOM_HALF_ALL_OBJS = $(call objs,$(LIBC_BOTTOM_HALF_ALL_SOURCES))
 LIBC_TOP_HALF_ALL_OBJS = $(call objs,$(LIBC_TOP_HALF_ALL_SOURCES))
-LIBC_OBJS := $(BASICS_OBJS)
 ifeq ($(BUILD_DLMALLOC),yes)
 LIBC_OBJS += $(DLMALLOC_OBJS)
 endif
-ifeq ($(BUILD_LIBC_BOTTOM_HALF),yes)
-# Override basics' string.o with libc-bottom-half's.
-LIBC_OBJS := $(filter-out %/string.o,$(LIBC_OBJS))
 # Add libc-bottom-half's objects.
 LIBC_OBJS += $(LIBC_BOTTOM_HALF_ALL_OBJS)
-endif
 ifeq ($(BUILD_LIBC_TOP_HALF),yes)
-# Override libc-bottom-half's string.o with libc-top-half's.
-LIBC_OBJS := $(filter-out %/string.o,$(LIBC_OBJS))
-# Override libc-bottom-half's qsort.o with libc-top-half's.
-LIBC_OBJS := $(filter-out %/qsort.o,$(LIBC_OBJS))
 # libc-top-half is musl.
 LIBC_OBJS += $(LIBC_TOP_HALF_ALL_OBJS)
 endif
@@ -405,7 +381,6 @@ include_dirs:
 	# Install the include files.
 	#
 	mkdir -p "$(SYSROOT_INC)"
-	cp -r "$(BASICS_INC)" "$(SYSROOT)"
 	cp -r "$(LIBC_BOTTOM_HALF_HEADERS_PUBLIC)"/* "$(SYSROOT_INC)"
 
 	# Generate musl's bits/alltypes.h header.
@@ -424,19 +399,13 @@ include_dirs:
 	# Remove selected header files.
 	$(RM) $(patsubst %,$(SYSROOT_INC)/%,$(MUSL_OMIT_HEADERS))
 
-ifeq ($(BUILD_LIBC_BOTTOM_HALF),no)
-CRT_SOURCES = $(BASICS_CRT_SOURCES)
-else
-CRT_SOURCES = $(LIBC_BOTTOM_HALF_CRT_SOURCES)
-endif
-
 startup_files: include_dirs
 	#
 	# Build the startup files.
 	#
 	@mkdir -p "$(OBJDIR)"
 	cd "$(OBJDIR)" && \
-	"$(WASM_CC)" $(WASM_CFLAGS) -c $(CRT_SOURCES) -MD -MP && \
+	"$(WASM_CC)" $(WASM_CFLAGS) -c $(LIBC_BOTTOM_HALF_CRT_SOURCES) -MD -MP && \
 	mkdir -p "$(SYSROOT_LIB)" && \
 	mv *.o "$(SYSROOT_LIB)"
 

basics/crt/crt1.c

@@ -1,23 +0,0 @@
-extern void __wasm_call_ctors(void);
-extern int __original_main(void);
-extern void __prepare_for_exit(void);
-void _Exit(int) __attribute__((noreturn));
-
-__attribute__((export_name("_start")))
-void _start(void) {
-    // The linker synthesizes this to call constructors.
-    __wasm_call_ctors();
-
-    // Call `__original_main` which will either be the application's zero-argument
-    // `__original_main` function or a libc routine which calls `__main_void`.
-    // TODO: Call `main` directly once we no longer have to support old compilers.
-    int r = __original_main();
-
-    // Call atexit functions, destructors, stdio cleanup, etc.
-    __prepare_for_exit();
-
-    // If main exited successfully, just return, otherwise call _Exit.
-    if (r != 0) {
-        _Exit(r);
-    }
-}

basics/include/__typedef_blksize_t.h

@@ -1,6 +0,0 @@
-#ifndef __wasm_basics___typedef_blksize_t_h
-#define __wasm_basics___typedef_blksize_t_h
-
-typedef long blksize_t;
-
-#endif

basics/include/__typedef_gid_t.h

@@ -1,6 +0,0 @@
-#ifndef __wasm_basics___typedef_gid_t_h
-#define __wasm_basics___typedef_gid_t_h
-
-typedef unsigned gid_t;
-
-#endif

basics/include/__typedef_mode_t.h

@@ -1,6 +0,0 @@
-#ifndef __wasm_basics___typedef_mode_t_h
-#define __wasm_basics___typedef_mode_t_h
-
-typedef unsigned mode_t;
-
-#endif

basics/include/__typedef_uid_t.h

@@ -1,6 +0,0 @@
-#ifndef __wasm_basics___typedef_uid_t_h
-#define __wasm_basics___typedef_uid_t_h
-
-typedef unsigned uid_t;
-
-#endif

basics/include/errno.h

@@ -1,6 +0,0 @@
-#ifndef __wasm_basics_errno_h
-#define __wasm_basics_errno_h
-
-#include <__errno.h>
-
-#endif

basics/include/stdlib.h

@@ -1,10 +0,0 @@
-#ifndef __wasm_basics_stdlib_h
-#define __wasm_basics_stdlib_h
-
-/*
- * Include the real implementation, which is factored into a separate file so
- * that it can be reused by other libc stdlib implementations.
- */
-#include <__functions_malloc.h>
-
-#endif

basics/include/string.h

@@ -1,10 +0,0 @@
-#ifndef __wasm_basics_string_h
-#define __wasm_basics_string_h
-
-/*
- * Include the real implementation, which is factored into a separate file so
- * that it can be reused by other libc string implementations.
- */
-#include <__functions_memcpy.h>
-
-#endif

basics/include/sys/stat.h

@@ -1,10 +0,0 @@
-#ifndef __wasm_basics_sys_stat_h
-#define __wasm_basics_sys_stat_h
-
-#include <__struct_stat.h>
-
-#define st_atime st_atim.tv_sec
-#define st_mtime st_mtim.tv_sec
-#define st_ctime st_ctim.tv_sec
-
-#endif

basics/include/sys/types.h

@@ -1,15 +0,0 @@
-#ifndef __wasm_basics_sys_types_h
-#define __wasm_basics_sys_types_h
-
-#define __need_size_t
-#include <stddef.h>
-
-#include <__typedef_clock_t.h>
-#include <__typedef_time_t.h>
-#include <__typedef_blksize_t.h>
-#include <__typedef_off_t.h>
-#include <__typedef_ssize_t.h>
-#include <__typedef_suseconds_t.h>
-#include <__typedef_nlink_t.h>
-
-#endif

basics/include/time.h

@@ -1,11 +0,0 @@
-#ifndef __wasm_basics_time_h
-#define __wasm_basics_time_h
-
-#define __need_size_t
-#define __need_NULL
-#include <stddef.h>
-
-#include <__typedef_time_t.h>
-#include <__struct_timespec.h>
-
-#endif

basics/sources/string.c

@@ -1,41 +0,0 @@
-#include <string.h>
-#include <stdint.h>
-
-static void *copy_forward(void *restrict dst, const void *restrict src, size_t n) {
-    char *d = (char *)dst;
-    const char *s = (const char *)src;
-    while (n-- != 0) {
-        *d++ = *s++;
-    }
-    return dst;
-}
-
-static void *copy_backward(void *restrict dst, const void *restrict src, size_t n) {
-    char *d = (char *)dst;
-    const char *s = (const char *)src;
-    d += n;
-    s += n;
-    while (n-- != 0) {
-        *--d = *--s;
-    }
-    return dst;
-}
-
-void *memcpy(void *restrict dst, const void *restrict src, size_t n) {
-    return copy_forward(dst, src, n);
-}
-
-void *memmove(void *dst, const void *src, size_t n) {
-    if ((uintptr_t)dst - (uintptr_t)src >= n) {
-        return copy_forward(dst, src, n);
-    }
-    return copy_backward(dst, src, n);
-}
-
-void *memset(void *restrict dst, int c, size_t n) {
-    char *d = (char *)dst;
-    while (n-- != 0) {
-        *d++ = c;
-    }
-    return dst;
-}

expected/wasm32-wasi/predefined-macros.txt

@@ -3021,9 +3021,12 @@
 #define __wasi_libc_environ_h 
 #define __wasi_libc_find_relpath_h 
 #define __wasi_libc_h 
+#define __wasilibc___errno_h 
 #define __wasilibc___errno_values_h 
 #define __wasilibc___fd_set_h 
 #define __wasilibc___function___isatty_h 
+#define __wasilibc___functions_malloc_h 
+#define __wasilibc___functions_memcpy_h 
 #define __wasilibc___header_dirent_h 
 #define __wasilibc___header_fcntl_h 
 #define __wasilibc___header_netinet_in_h 
@@ -3036,7 +3039,9 @@
 #define __wasilibc___header_sys_stat_h 
 #define __wasilibc___header_time_h 
 #define __wasilibc___header_unistd_h 
+#define __wasilibc___include_inttypes_h 
 #define __wasilibc___macro_FD_SETSIZE_h 
+#define __wasilibc___macro_PAGESIZE_h 
 #define __wasilibc___mode_t_h 
 #define __wasilibc___seek_h 
 #define __wasilibc___struct_dirent_h 
@@ -3051,42 +3056,37 @@
 #define __wasilibc___struct_sockaddr_in_h 
 #define __wasilibc___struct_sockaddr_storage_h 
 #define __wasilibc___struct_sockaddr_un_h 
+#define __wasilibc___struct_stat_h 
+#define __wasilibc___struct_timespec_h 
 #define __wasilibc___struct_timeval_h 
 #define __wasilibc___struct_tm_h 
 #define __wasilibc___struct_tms_h 
 #define __wasilibc___typedef_DIR_h 
+#define __wasilibc___typedef_blkcnt_t_h 
+#define __wasilibc___typedef_blksize_t_h 
+#define __wasilibc___typedef_clock_t_h 
 #define __wasilibc___typedef_clockid_t_h 
+#define __wasilibc___typedef_dev_t_h 
 #define __wasilibc___typedef_fd_set_h 
+#define __wasilibc___typedef_gid_t_h 
 #define __wasilibc___typedef_in_addr_t_h 
 #define __wasilibc___typedef_in_port_t_h 
+#define __wasilibc___typedef_ino_t_h 
+#define __wasilibc___typedef_mode_t_h 
 #define __wasilibc___typedef_nfds_t_h 
+#define __wasilibc___typedef_nlink_t_h 
+#define __wasilibc___typedef_off_t_h 
 #define __wasilibc___typedef_sa_family_t_h 
 #define __wasilibc___typedef_sigset_t_h 
 #define __wasilibc___typedef_socklen_t_h 
+#define __wasilibc___typedef_ssize_t_h 
+#define __wasilibc___typedef_suseconds_t_h 
+#define __wasilibc___typedef_time_t_h 
+#define __wasilibc___typedef_uid_t_h 
 #define __wasm 1
 #define __wasm32 1
 #define __wasm32__ 1
 #define __wasm__ 1
-#define __wasm_basics___errno_h 
-#define __wasm_basics___functions_malloc_h 
-#define __wasm_basics___functions_memcpy_h 
-#define __wasm_basics___include_inttypes_h 
-#define __wasm_basics___macro_PAGESIZE_h 
-#define __wasm_basics___struct_stat_h 
-#define __wasm_basics___struct_timespec_h 
-#define __wasm_basics___typedef_blkcnt_t_h 
-#define __wasm_basics___typedef_blksize_t_h 
-#define __wasm_basics___typedef_clock_t_h 
-#define __wasm_basics___typedef_dev_t_h 
-#define __wasm_basics___typedef_gid_t_h 
-#define __wasm_basics___typedef_ino_t_h 
-#define __wasm_basics___typedef_mode_t_h 
-#define __wasm_basics___typedef_nlink_t_h 
-#define __wasm_basics___typedef_off_t_h 
-#define __wasm_basics___typedef_ssize_t_h 
-#define __wasm_basics___typedef_suseconds_t_h 
-#define __wasm_basics___typedef_time_t_h 
-#define __wasm_basics___typedef_uid_t_h 
 #define _tolower(a) ((a)|0x20)
 #define _toupper(a) ((a)&0x5f)
 #define acos(x) __tg_real_complex(acos, (x))

libc-bottom-half/README.md

@@ -16,5 +16,4 @@ libc rather than to be a layer on top of libc.
 
 [libpreopen]: https://github.com/musec/libpreopen
 
-The WASI libc "bottom half" depends on the basics and dlmalloc components of
-wasi-libc.
+The WASI libc lower half currently depends on the dlmalloc component.

libc-bottom-half/cloudlibc/src/libc/stdlib/qsort.c

@@ -1,15 +0,0 @@
-// Copyright (c) 2015 Nuxi, https://nuxi.nl/
-//
-// SPDX-License-Identifier: BSD-2-Clause
-
-#include <stdlib.h>
-
-#ifndef qsort
-#error "qsort is supposed to be a macro as well"
-#endif
-
-// clang-format off
-void (qsort)(void *base, size_t nel, size_t width,
-             int (*compar)(const void *, const void *)) {
-  return qsort(base, nel, width, compar);
-}

libc-bottom-half/headers/public/__errno.h

@@ -1,5 +1,5 @@
-#ifndef __wasm_basics___errno_h
-#define __wasm_basics___errno_h
+#ifndef __wasilibc___errno_h
+#define __wasilibc___errno_h
 
 #ifdef __cplusplus
 extern "C" {

libc-bottom-half/headers/public/__functions_malloc.h

@@ -1,5 +1,5 @@
-#ifndef __wasm_basics___functions_malloc_h
-#define __wasm_basics___functions_malloc_h
+#ifndef __wasilibc___functions_malloc_h
+#define __wasilibc___functions_malloc_h
 
 #define __need_size_t
 #define __need_wchar_t

libc-bottom-half/headers/public/__functions_memcpy.h

@@ -1,5 +1,5 @@
-#ifndef __wasm_basics___functions_memcpy_h
-#define __wasm_basics___functions_memcpy_h
+#ifndef __wasilibc___functions_memcpy_h
+#define __wasilibc___functions_memcpy_h
 
 #define __need_size_t
 #define __need_NULL

libc-bottom-half/headers/public/__header_inttypes.h

@@ -1,5 +1,5 @@
-#ifndef __wasm_basics___include_inttypes_h
-#define __wasm_basics___include_inttypes_h
+#ifndef __wasilibc___include_inttypes_h
+#define __wasilibc___include_inttypes_h
 
 #include <stdint.h>
 

libc-bottom-half/headers/public/__macro_PAGESIZE.h

@@ -1,5 +1,5 @@
-#ifndef __wasm_basics___macro_PAGESIZE_h
-#define __wasm_basics___macro_PAGESIZE_h
+#ifndef __wasilibc___macro_PAGESIZE_h
+#define __wasilibc___macro_PAGESIZE_h
 
 /*
  * The page size in WebAssembly is fixed at 64 KiB. If this ever changes,

libc-bottom-half/headers/public/__struct_stat.h

@@ -1,5 +1,5 @@
-#ifndef __wasm_basics___struct_stat_h
-#define __wasm_basics___struct_stat_h
+#ifndef __wasilibc___struct_stat_h
+#define __wasilibc___struct_stat_h
 
 #include <__typedef_dev_t.h>
 #include <__typedef_ino_t.h>

libc-bottom-half/headers/public/__struct_timespec.h

@@ -1,5 +1,5 @@
-#ifndef __wasm_basics___struct_timespec_h
-#define __wasm_basics___struct_timespec_h
+#ifndef __wasilibc___struct_timespec_h
+#define __wasilibc___struct_timespec_h
 
 #include <__typedef_time_t.h>
 

libc-bottom-half/headers/public/__typedef_blkcnt_t.h

@@ -1,5 +1,5 @@
-#ifndef __wasm_basics___typedef_blkcnt_t_h
-#define __wasm_basics___typedef_blkcnt_t_h
+#ifndef __wasilibc___typedef_blkcnt_t_h
+#define __wasilibc___typedef_blkcnt_t_h
 
 /* Define these as 64-bit signed integers to support files larger than 2 GiB. */
 typedef long long blkcnt_t;

libc-bottom-half/headers/public/__typedef_blksize_t.h

@@ -0,0 +1,6 @@
+#ifndef __wasilibc___typedef_blksize_t_h
+#define __wasilibc___typedef_blksize_t_h
+
+typedef long blksize_t;
+
+#endif

libc-bottom-half/headers/public/__typedef_clock_t.h

@@ -1,5 +1,5 @@
-#ifndef __wasm_basics___typedef_clock_t_h
-#define __wasm_basics___typedef_clock_t_h
+#ifndef __wasilibc___typedef_clock_t_h
+#define __wasilibc___typedef_clock_t_h
 
 /* Define this as a 64-bit signed integer to avoid wraparounds. */
 typedef long long clock_t;

libc-bottom-half/headers/public/__typedef_dev_t.h

@@ -1,5 +1,5 @@
-#ifndef __wasm_basics___typedef_dev_t_h
-#define __wasm_basics___typedef_dev_t_h
+#ifndef __wasilibc___typedef_dev_t_h
+#define __wasilibc___typedef_dev_t_h
 
 /* Define these as 64-bit integers to support billions of devices. */
 typedef unsigned long long dev_t;

libc-bottom-half/headers/public/__typedef_gid_t.h

@@ -0,0 +1,6 @@
+#ifndef __wasilibc___typedef_gid_t_h
+#define __wasilibc___typedef_gid_t_h
+
+typedef unsigned gid_t;
+
+#endif

libc-bottom-half/headers/public/__typedef_ino_t.h

@@ -1,5 +1,5 @@
-#ifndef __wasm_basics___typedef_ino_t_h
-#define __wasm_basics___typedef_ino_t_h
+#ifndef __wasilibc___typedef_ino_t_h
+#define __wasilibc___typedef_ino_t_h
 
 /* Define these as 64-bit integers to support billions of inodes. */
 typedef unsigned long long ino_t;

libc-bottom-half/headers/public/__typedef_mode_t.h

@@ -0,0 +1,6 @@
+#ifndef __wasilibc___typedef_mode_t_h
+#define __wasilibc___typedef_mode_t_h
+
+typedef unsigned mode_t;
+
+#endif

libc-bottom-half/headers/public/__typedef_nlink_t.h

@@ -1,5 +1,5 @@
-#ifndef __wasm_basics___typedef_nlink_t_h
-#define __wasm_basics___typedef_nlink_t_h
+#ifndef __wasilibc___typedef_nlink_t_h
+#define __wasilibc___typedef_nlink_t_h
 
 /* Define these as 64-bit unsigned integers to support billions of links. */
 typedef unsigned long long nlink_t;

libc-bottom-half/headers/public/__typedef_off_t.h

@@ -1,5 +1,5 @@
-#ifndef __wasm_basics___typedef_off_t_h
-#define __wasm_basics___typedef_off_t_h
+#ifndef __wasilibc___typedef_off_t_h
+#define __wasilibc___typedef_off_t_h
 
 /* Define these as 64-bit signed integers to support files larger than 2 GiB. */
 typedef long long off_t;

libc-bottom-half/headers/public/__typedef_ssize_t.h

@@ -1,5 +1,5 @@
-#ifndef __wasm_basics___typedef_ssize_t_h
-#define __wasm_basics___typedef_ssize_t_h
+#ifndef __wasilibc___typedef_ssize_t_h
+#define __wasilibc___typedef_ssize_t_h
 
 /* This is defined to be the same size as size_t. */
 typedef long ssize_t;

libc-bottom-half/headers/public/__typedef_suseconds_t.h

@@ -1,5 +1,5 @@
-#ifndef __wasm_basics___typedef_suseconds_t_h
-#define __wasm_basics___typedef_suseconds_t_h
+#ifndef __wasilibc___typedef_suseconds_t_h
+#define __wasilibc___typedef_suseconds_t_h
 
 /* Define this to be 64-bit as its main use is in struct timeval where the
    extra space would otherwise be padding. */

libc-bottom-half/headers/public/__typedef_time_t.h

@@ -1,5 +1,5 @@
-#ifndef __wasm_basics___typedef_time_t_h
-#define __wasm_basics___typedef_time_t_h
+#ifndef __wasilibc___typedef_time_t_h
+#define __wasilibc___typedef_time_t_h
 
 /* Define this as a 64-bit signed integer to avoid the 2038 bug. */
 typedef long long time_t;

libc-bottom-half/headers/public/__typedef_uid_t.h

@@ -0,0 +1,6 @@
+#ifndef __wasilibc___typedef_uid_t_h
+#define __wasilibc___typedef_uid_t_h
+
+typedef unsigned uid_t;
+
+#endif

libc-bottom-half/headers/public/inttypes.h

@@ -1,5 +1,5 @@
-#ifndef __wasm_basics_inttypes_h
-#define __wasm_basics_inttypes_h
+#ifndef __wasilibc_inttypes_h
+#define __wasilibc_inttypes_h
 
 /*
  * Include the real implementation, which is factored into a separate file so

libc-bottom-half/headers/public/stdlib.h

@@ -5,6 +5,6 @@
  * Include the real implementation, which is factored into a separate file so
  * that it can be reused by other libc stdlib implementations.
  */
-#include <__header_stdlib.h>
+#include <__functions_malloc.h>
 
 #endif

libc-bottom-half/headers/public/wchar.h

@@ -1,5 +1,5 @@
-#ifndef __wasm_basics_wchar_h
-#define __wasm_basics_wchar_h
+#ifndef __wasilibc_wchar_h
+#define __wasilibc_wchar_h
 
 #define __need_size_t
 #define __need_wchar_t

libc-bottom-half/sources/errno.c

@@ -1,5 +1,4 @@
 #include <errno.h>
-#include <threads.h>
 
 // These values are used by reference-sysroot's dlmalloc.
 const int __EINVAL = EINVAL;

libc-bottom-half/sources/string.c

@@ -1,40 +0,0 @@
-#include <string.h>
-#include <stdint.h>
-#include <stdlib.h>
-
-size_t strlen(const char *str) {
-    const char *s = str;
-    while (*s) {
-        ++s;
-    }
-    return s - str;
-}
-
-char *strdup(const char *str) {
-    size_t buf_len = strlen(str) + 1;
-    void *ptr = malloc(buf_len);
-    if (ptr == NULL) {
-        return NULL;
-    }
-    return memcpy(ptr, str, buf_len);
-}
-
-int strcmp(const char *a, const char *b) {
-    while (*a != '\0' && (*a == *b)) {
-        ++a;
-        ++b;
-    }
-    return *(const unsigned char*)a - *(const unsigned char*)b;
-}
-
-void *memchr(const void *ptr, int c, size_t len) {
-    const unsigned char *p = ptr;
-    while (len != 0 && *p != (unsigned char)c) {
-        ++p;
-        --len;
-    }
-    if (len == 0) {
-        return NULL;
-    }
-    return (void *)p;
-}