--- /dev/null
+# SPDX-License-Identifier: GPL-2.0-only
+########################################################################
+#
+# (C) Copyright 2021, Alejandro Colomar
+# These functions are free software; you can redistribute them and/or
+# modify them under the terms of the GNU General Public License
+# as published by the Free Software Foundation; version 2.
+#
+# These functions are distributed in the hope that they will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details
+# (http://www.gnu.org/licenses/gpl-2.0.html).
+#
+########################################################################
+
+########################################################################
+# Exit status
+
+EX_OK=0;
+EX_USAGE=64;
+
+########################################################################
+# Linux kernel
+
+# grep_syscall() finds the prototype of a syscall in the kernel sources,
+# printing the filename, line number, and the prototype.
+# It should be run from the root of the linux kernel source tree.
+# Usage example: .../linux$ grep_syscall openat2;
+
+function grep_syscall()
+{
+ if ! [ -v 1 ]; then
+ >&2 echo "Usage: ${FUNCNAME[0]} <syscall>";
+ return ${EX_USAGE};
+ fi
+
+ find * -type f \
+ |grep '\.c$' \
+ |sort -V \
+ |xargs pcregrep -Mn "(?s)^\w*SYSCALL_DEFINE.\(${1},.*?\)" \
+ |sed -E 's/^[^:]+:[0-9]+:/&\n/';
+
+ find * -type f \
+ |grep '\.[ch]$' \
+ |sort -V \
+ |xargs pcregrep -Mn "(?s)^asmlinkage\s+[\w\s]+\**sys_${1}\s*\(.*?\)" \
+ |sed -E 's/^[^:]+:[0-9]+:/&\n/';
+}
+
+# grep_syscall_def() finds the definition of a syscall in the kernel sources,
+# printing the filename, line number, and the function definition.
+# It should be run from the root of the linux kernel source tree.
+# Usage example: .../linux$ grep_syscall_def openat2;
+
+function grep_syscall_def()
+{
+ if ! [ -v 1 ]; then
+ >&2 echo "Usage: ${FUNCNAME[0]} <syscall>";
+ return ${EX_USAGE};
+ fi
+
+ find * -type f \
+ |grep '\.c$' \
+ |sort -V \
+ |xargs pcregrep -Mn "(?s)^\w*SYSCALL_DEFINE.\(${1},.*?^}" \
+ |sed -E 's/^[^:]+:[0-9]+:/&\n/';
+}
+
+########################################################################
+# Linux man-pages
+
+# man_section() prints a specific manual page section (DESCRIPTION, SYNOPSIS,
+# ...) of all manual pages in a directory (or in a single manual page file).
+# Usage example: .../man-pages$ man_section man2 SYNOPSIS;
+
+function man_section()
+{
+ if ! [ -v 2 ]; then
+ >&2 echo "Usage: ${FUNCNAME[0]} <dir> <section>";
+ return ${EX_USAGE};
+ fi
+
+ find "${1}" -type f \
+ |xargs grep -l "\.SH ${2}" \
+ |sort -V \
+ |while read -r manpage; do
+ <${manpage} \
+ sed -n \
+ -e '/^\.TH/,/^\.SH/{/^\.SH/!p}' \
+ -e "/^\.SH ${2}/p" \
+ -e "/^\.SH ${2}/,/^\.SH/{/^\.SH/!p}" \
+ |man -P cat -l - 2>/dev/null;
+ done;
+}
+
+# man_lsfunc() prints the name of all C functions declared in the SYNOPSIS
+# of all manual pages in a directory (or in a single manual page file).
+# Each name is printed in a separate line
+# Usage example: .../man-pages$ man_lsfunc man2;
+
+function man_lsfunc()
+{
+ if ! [ -v 1 ]; then
+ >&2 echo "Usage: ${FUNCNAME[0]} <dir>";
+ return ${EX_USAGE};
+ fi
+
+ find "${@}" -type f \
+ |xargs grep -l "\.SH SYNOPSIS" \
+ |sort -V \
+ |while read -r manpage; do
+ <${manpage} \
+ sed -n \
+ -e '/^\.TH/,/^\.SH/{/^\.SH/!p}' \
+ -e "/^\.SH SYNOPSIS/p" \
+ -e "/^\.SH SYNOPSIS/,/^\.SH/{/^\.SH/!p}" \
+ |sed \
+ -e '/Feature/,$d' \
+ -e '/{/,/}/d' \
+ |man -P cat -l - 2>/dev/null;
+ done \
+ |sed -n "/^SYNOPSIS/,/^\w/p" \
+ |grep '^ \w' \
+ |grep -v ':' \
+ |sed 's/^[^(]* \**\(\w*\)(.*/\1/' \
+ |grep '^\w' \
+ |uniq;
+}
+
+# pdfman() reanders a manual page in PDF
+# Usage example: .../man-pages$ pdfman man2/membarrier.2;
+
+function pdfman()
+{
+ if ! [ -v 1 ]; then
+ >&2 echo "Usage: ${FUNCNAME[0]} <man-page.n>";
+ return ${EX_USAGE};
+ fi;
+
+ local tmp="$(mktemp -t "${1##*/}.XXXXXX")";
+
+ <${1} \
+ man -Tps -l - \
+ |ps2pdf - - \
+ >${tmp};
+ xdg-open ${tmp};
+}
+
+########################################################################
+# Glibc
+
+# grep_glibc_prototype() finds a function prototype in the glibc sources,
+# printing the filename, line number, and the prototype.
+# It should be run from the root of the glibc source tree.
+# Usage example: .../glibc$ grep_glibc_prototype printf;
+
+function grep_glibc_prototype()
+{
+ if ! [ -v 1 ]; then
+ >&2 echo "Usage: ${FUNCNAME[0]} <func>";
+ return ${EX_USAGE};
+ fi
+
+ find * -type f \
+ |grep '\.h$' \
+ |sort -V \
+ |xargs pcregrep -Mn \
+ "(?s)^[\w[][\w\s(,)[:\]]+\s+\**${1}\s*\([\w\s(,)[\]*]+?(...)?\)[\w\s(,)[:\]]*;" \
+ |sed -E 's/^[^:]+:[0-9]+:/&\n/';
+}