lib/string/strcpy/, lib/, src/, tests/: Move all copying APIs to a subdirectory

Signed-off-by: Alejandro Colomar <alx@kernel.org>

lib/string/strcpy/stpecpy.c

@@ -0,0 +1,12 @@
+// SPDX-FileCopyrightText: 2022-2024, Alejandro Colomar <alx@kernel.org>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#include <config.h>
+
+#include "string/strcpy/stpecpy.h"
+
+
+#if !defined(HAVE_STPECPY)
+extern inline char *stpecpy(char *dst, char *end, const char *restrict src);
+#endif

lib/string/strcpy/stpecpy.h

@@ -0,0 +1,88 @@
+// SPDX-FileCopyrightText: 2022-2024, Alejandro Colomar <alx@kernel.org>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#ifndef SHADOW_INCLUDE_LIB_STRING_STRCPY_STPECPY_H_
+#define SHADOW_INCLUDE_LIB_STRING_STRCPY_STPECPY_H_
+
+
+#include <config.h>
+
+#include <stdbool.h>
+#include <stddef.h>
+#include <string.h>
+
+#include "attr.h"
+
+
+#if !defined(HAVE_STPECPY)
+ATTR_STRING(3)
+inline char *stpecpy(char *dst, char *end, const char *restrict src);
+#endif
+
+
+/*
+ * SYNOPSIS
+ *	[[gnu::null_terminated_string_arg(3)]]
+ *	char *_Nullable stpecpy(char *_Nullable dst, char end[0],
+ *	                        const char *restrict src);
+ *
+ * ARGUMENTS
+ *	dst	Destination buffer where to copy a string.
+ *
+ *	end	Pointer to one after the last element of the buffer
+ *		pointed to by `dst`.  Usually, it should be calculated
+ *		as `dst + NITEMS(dst)`.
+ *
+ *	src	Source string to be copied into dst.
+ *
+ * DESCRIPTION
+ *	This function copies the string pointed to by src, into a string
+ *	at the buffer pointed to by dst.  If the destination buffer,
+ *	limited by a pointer to its end --one after its last element--,
+ *	isn't large enough to hold the copy, the resulting string is
+ *	truncated.
+ *
+ *	This function can be chained with calls to [v]stpeprintf().
+ *
+ * RETURN VALUE
+ *	dst + strlen(dst)
+ *		•  On success, this function returns a pointer to the
+ *		   terminating NUL byte.
+ *
+ *	end
+ *		•  If this call truncated the resulting string.
+ *		•  If `dst == end` (a previous chained call to these
+ *		   functions truncated).
+ *	NULL
+ *		•  If `dst == NULL` (a previous chained call to
+ *		   [v]stpeprintf() failed).
+ *
+ * ERRORS
+ *	This function doesn't set errno.
+ */
+
+
+#if !defined(HAVE_STPECPY)
+inline char *
+stpecpy(char *dst, char *end, const char *restrict src)
+{
+	bool    trunc;
+	size_t  dsize, dlen, slen;
+
+	if (dst == end)
+		return end;
+	if (dst == NULL)
+		return NULL;
+
+	dsize = end - dst;
+	slen = strnlen(src, dsize);
+	trunc = (slen == dsize);
+	dlen = slen - trunc;
+
+	return stpcpy(mempcpy(dst, src, dlen), "") + trunc;
+}
+#endif
+
+
+#endif  // include guard

lib/string/strcpy/strncpy.c

@@ -0,0 +1,7 @@
+// SPDX-FileCopyrightText: 2024, Alejandro Colomar <alx@kernel.org>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#include <config.h>
+
+#include "string/strcpy/strncpy.h"

lib/string/strcpy/strncpy.h

@@ -0,0 +1,19 @@
+// SPDX-FileCopyrightText: 2024, Alejandro Colomar <alx@kernel.org>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#ifndef SHADOW_INCLUDE_LIB_STRING_STRCPY_STRNCPY_H_
+#define SHADOW_INCLUDE_LIB_STRING_STRCPY_STRNCPY_H_
+
+
+#include <config.h>
+
+#include <string.h>
+
+#include "sizeof.h"
+
+
+#define STRNCPY(dst, src)  strncpy(dst, src, NITEMS(dst))
+
+
+#endif  // include guard

lib/string/strcpy/strtcpy.c

@@ -0,0 +1,14 @@
+// SPDX-FileCopyrightText: 2022-2024, Alejandro Colomar <alx@kernel.org>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#include <config.h>
+
+#include <stddef.h>
+#include <sys/types.h>
+
+#include "string/strcpy/strtcpy.h"
+
+
+extern inline ssize_t strtcpy(char *restrict dst, const char *restrict src,
+    size_t dsize);

lib/string/strcpy/strtcpy.h

@@ -0,0 +1,77 @@
+// SPDX-FileCopyrightText: 2023-2024, Alejandro Colomar <alx@kernel.org>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#ifndef SHADOW_INCLUDE_LIB_STRING_STRCPY_STRTCPY_H_
+#define SHADOW_INCLUDE_LIB_STRING_STRCPY_STRTCPY_H_
+
+
+#include <config.h>
+
+#include <stdbool.h>
+#include <stddef.h>
+#include <string.h>
+#include <sys/types.h>
+
+#include "attr.h"
+#include "sizeof.h"
+
+
+/*
+ * SYNOPSIS
+ *	[[gnu::null_terminated_string_arg(2)]]
+ *	int STRTCPY(char dst[restrict], const char *restrict src);
+ *
+ * ARGUMENTS
+ *	dst	Destination buffer where to copy a string.
+ *	src	Source string to be copied into dst.
+ *
+ * DESCRIPTION
+ *	This macro copies the string pointed to by src, into a string
+ *	at the buffer pointed to by dst.  If the destination buffer,
+ *	isn't large enough to hold the copy, the resulting string is
+ *	truncated.  The size of the buffer is calculated internally via
+ *	NITEMS().
+ *
+ * RETURN VALUE
+ *	-1	If this call truncated the resulting string.
+ *
+ *	strlen(dst)
+ *		On success.
+ *
+ * ERRORS
+ *	This function doesn't set errno.
+ */
+
+
+#define STRTCPY(dst, src)  strtcpy(dst, src, NITEMS(dst))
+
+
+ATTR_STRING(2)
+inline ssize_t strtcpy(char *restrict dst, const char *restrict src,
+    size_t dsize);
+
+
+inline ssize_t
+strtcpy(char *restrict dst, const char *restrict src, size_t dsize)
+{
+	bool    trunc;
+	size_t  dlen, slen;
+
+	if (dsize == 0)
+		return -1;
+
+	slen = strnlen(src, dsize);
+	trunc = (slen == dsize);
+	dlen = slen - trunc;
+
+	stpcpy(mempcpy(dst, src, dlen), "");
+
+	if (trunc)
+		return -1;
+
+	return slen;
+}
+
+
+#endif  // include guard

lib/string/strcpy/zustr2stp.c

@@ -0,0 +1,7 @@
+// SPDX-FileCopyrightText: 2022-2024, Alejandro Colomar <alx@kernel.org>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#include <config.h>
+
+#include "string/strcpy/zustr2stp.h"

lib/string/strcpy/zustr2stp.h

@@ -0,0 +1,58 @@
+// SPDX-FileCopyrightText: 2022-2024, Alejandro Colomar <alx@kernel.org>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#ifndef SHADOW_INCLUDE_LIB_STRING_STRCPY_ZUSTR2STP_H_
+#define SHADOW_INCLUDE_LIB_STRING_STRCPY_ZUSTR2STP_H_
+
+
+#include <config.h>
+
+#include <assert.h>
+#include <string.h>
+
+#include "must_be.h"
+#include "sizeof.h"
+
+
+/*
+ * SYNOPSIS
+ *	char *ZUSTR2STP(char *restrict dst, const char src[restrict]);
+ *
+ * ARGUMENTS
+ *	dst	Destination buffer.
+ *	src	Source null-padded character sequence.
+ *
+ * DESCRIPTION
+ *	This macro copies at most NITEMS(src) non-null bytes from the
+ *	array pointed to by src, followed by a null character, to the
+ *	buffer pointed to by dst.
+ *
+ * RETURN VALUE
+ *	dst + strlen(dst)
+ *		This function returns a pointer to the terminating NUL
+ *		byte.
+ *
+ * CAVEATS
+ *	This function doesn't know the size of the destination buffer.
+ *	It assumes it will always be large enough.  Since the size of
+ *	the source buffer is known to the caller, it should make sure to
+ *	allocate a destination buffer of at least `NITEMS(src) + 1`.
+ *
+ * EXAMPLES
+ *	char  hostname[NITEMS(utmp->ut_host) + 1];
+ *
+ *	len = ZUSTR2STP(hostname, utmp->ut_host) - hostname;
+ *	puts(hostname);
+ */
+
+
+#define ZUSTR2STP(dst, src)                                                   \
+({                                                                            \
+	static_assert(!is_array(dst) || sizeof(dst) > SIZEOF_ARRAY(src), ""); \
+                                                                              \
+	stpcpy(mempcpy(dst, src, strnlen(src, NITEMS(src))), "");             \
+})
+
+
+#endif  // include guard