lib/string/strchr/: stp[c]spn(), strrspn(), strnul(): Add macros and functions

Often, a pointer is more useful than a length when calling these.

Link: <https://docs.oracle.com/cd/E86824_01/html/E54769/strrspn-3gen.html>
Signed-off-by: Alejandro Colomar <alx@kernel.org>

diff --git a/lib/Makefile.am b/lib/Makefile.am
index fb509555d6cffbc263b7698b6e60943e5153c835..8cbb6dfdb51f0d438414232a6cffd6629e687d1a 100644 (file)
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -162,6 +162,14 @@ libshadow_la_SOURCES = \
        string/sprintf/stpeprintf.h \
        string/sprintf/xasprintf.c \
        string/sprintf/xasprintf.h \
+       string/strchr/stpcspn.c \
+       string/strchr/stpcspn.h \
+       string/strchr/stpspn.c \
+       string/strchr/stpspn.h \
+       string/strchr/strnul.c \
+       string/strchr/strnul.h \
+       string/strchr/strrspn.c \
+       string/strchr/strrspn.h \
        string/strcpy/stpecpy.c \
        string/strcpy/stpecpy.h \
        string/strcpy/strncat.c \

diff --git a/lib/string/strchr/stpcspn.c b/lib/string/strchr/stpcspn.c
new file mode 100644 (file)
index 0000000..7094f18
--- /dev/null
+++ b/lib/string/strchr/stpcspn.c
@@ -0,0 +1,7 @@
+// SPDX-FileCopyrightText: 2024, Alejandro Colomar <alx@kernel.org>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#include <config.h>
+
+#include "string/strchr/stpcspn.h"

diff --git a/lib/string/strchr/stpcspn.h b/lib/string/strchr/stpcspn.h
new file mode 100644 (file)
index 0000000..9fa78d3
--- /dev/null
+++ b/lib/string/strchr/stpcspn.h
@@ -0,0 +1,27 @@
+// SPDX-FileCopyrightText: 2024, Alejandro Colomar <alx@kernel.org>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#ifndef SHADOW_INCLUDE_LIB_STRING_STRCHR_STPCSPN_H_
+#define SHADOW_INCLUDE_LIB_STRING_STRCHR_STPCSPN_H_
+
+
+#include <config.h>
+
+#include <string.h>
+
+#include "attr.h"
+
+
+// Similar to strcspn(3), but return a pointer instead of an offset.
+// Similar to strchrnul(3), but search for several delimiters.
+// Similar to strpbrk(3), but return 's + strlen(s)' if not found.
+#define stpcspn(s, reject)                                                    \
+({                                                                            \
+       __auto_type  s_ = s;                                                  \
+                                                                              \
+       s_ + strcspn(s_, reject);                                             \
+})
+
+
+#endif  // include guard

diff --git a/lib/string/strchr/stpspn.c b/lib/string/strchr/stpspn.c
new file mode 100644 (file)
index 0000000..b94ffe1
--- /dev/null
+++ b/lib/string/strchr/stpspn.c
@@ -0,0 +1,7 @@
+// SPDX-FileCopyrightText: 2024, Alejandro Colomar <alx@kernel.org>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#include <config.h>
+
+#include "string/strchr/stpspn.h"

diff --git a/lib/string/strchr/stpspn.h b/lib/string/strchr/stpspn.h
new file mode 100644 (file)
index 0000000..97edfdf
--- /dev/null
+++ b/lib/string/strchr/stpspn.h
@@ -0,0 +1,26 @@
+// SPDX-FileCopyrightText: 2024, Alejandro Colomar <alx@kernel.org>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#ifndef SHADOW_INCLUDE_LIB_STRING_STRCHR_STPSPN_H_
+#define SHADOW_INCLUDE_LIB_STRING_STRCHR_STPSPN_H_
+
+
+#include <config.h>
+
+#include <string.h>
+
+#include "attr.h"
+
+
+// Similar to strspn(3), but return a pointer instead of an offset.
+// Similar to strchrnul(3), but search for any bytes not in 'accept'.
+#define stpspn(s, accept)                                                     \
+({                                                                            \
+       __auto_type  s_ = s;                                                  \
+                                                                              \
+       s_ + strspn(s_, accept);                                              \
+})
+
+
+#endif  // include guard

diff --git a/lib/string/strchr/strnul.c b/lib/string/strchr/strnul.c
new file mode 100644 (file)
index 0000000..93b3ab7
--- /dev/null
+++ b/lib/string/strchr/strnul.c
@@ -0,0 +1,7 @@
+// SPDX-FileCopyrightText: 2024, Alejandro Colomar <alx@kernel.org>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#include <config.h>
+
+#include "string/strchr/strnul.h"

diff --git a/lib/string/strchr/strnul.h b/lib/string/strchr/strnul.h
new file mode 100644 (file)
index 0000000..5754ad0
--- /dev/null
+++ b/lib/string/strchr/strnul.h
@@ -0,0 +1,25 @@
+// SPDX-FileCopyrightText: 2024, Alejandro Colomar <alx@kernel.org>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#ifndef SHADOW_INCLUDE_LIB_STRING_STRCHR_STRNUL_H_
+#define SHADOW_INCLUDE_LIB_STRING_STRCHR_STRNUL_H_
+
+
+#include <config.h>
+
+#include <string.h>
+
+#include "attr.h"
+
+
+// Similar to strlen(3), but return a pointer instead of an offset.
+#define strnul(s)                                                             \
+({                                                                            \
+       __auto_type  s_ = s;                                                  \
+                                                                              \
+       s_ + strlen(s_);                                                      \
+})
+
+
+#endif  // include guard

diff --git a/lib/string/strchr/strrspn.c b/lib/string/strchr/strrspn.c
new file mode 100644 (file)
index 0000000..7ba2547
--- /dev/null
+++ b/lib/string/strchr/strrspn.c
@@ -0,0 +1,10 @@
+// SPDX-FileCopyrightText: 2024, Alejandro Colomar <alx@kernel.org>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#include <config.h>
+
+#include "string/strchr/strrspn.h"
+
+
+extern inline char *strrspn(char *restrict s, const char *restrict accept);

diff --git a/lib/string/strchr/strrspn.h b/lib/string/strchr/strrspn.h
new file mode 100644 (file)
index 0000000..c05dc56
--- /dev/null
+++ b/lib/string/strchr/strrspn.h
@@ -0,0 +1,38 @@
+// SPDX-FileCopyrightText: 2024, Alejandro Colomar <alx@kernel.org>
+// SPDX-License-Identifier: BSD-3-Clause
+
+
+#ifndef SHADOW_INCLUDE_LIB_STRING_STRCHR_STRRSPN_H_
+#define SHADOW_INCLUDE_LIB_STRING_STRCHR_STRRSPN_H_
+
+
+#include <config.h>
+
+#include <string.h>
+
+#include "attr.h"
+#include "string/strchr/strnul.h"
+
+
+ATTR_STRING(2)
+inline char *strrspn(char *restrict s, const char *restrict accept);
+
+
+// Available in Oracle Solaris: strrspn(3GEN).
+// <https://docs.oracle.com/cd/E36784_01/html/E36877/strrspn-3gen.html>
+inline char *
+strrspn(char *restrict s, const char *restrict accept)
+{
+       char  *p;
+
+       p = strnul(s);
+       while (p > s) {
+               p--;
+               if (strchr(accept, *p) == NULL)
+                       return p + 1;
+       }
+       return s;
+}
+
+
+#endif  // include guard