Merging upstream version 1.11.0+dfsg.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

5 files changed, 548 insertions, 28 deletions

diff --git a/libnetdata/procfile/Makefile.am b/libnetdata/procfile/Makefile.am
new file mode 100644
index 00000000..1cb69ed9
--- /dev/null
+++ b/libnetdata/procfile/Makefile.am
@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+AUTOMAKE_OPTIONS = subdir-objects
+MAINTAINERCLEANFILES = $(srcdir)/Makefile.in
+
+
+dist_noinst_DATA = \
+	README.md \
+	$(NULL)
diff --git a/libnetdata/procfile/Makefile.in b/libnetdata/procfile/Makefile.in
new file mode 100644
index 00000000..643e00ba
--- /dev/null
+++ b/libnetdata/procfile/Makefile.in
@@ -0,0 +1,464 @@
+# Makefile.in generated by automake 1.14.1 from Makefile.am.
+# @configure_input@
+
+# Copyright (C) 1994-2013 Free Software Foundation, Inc.
+
+# This Makefile.in is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY, to the extent permitted by law; without
+# even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+# PARTICULAR PURPOSE.
+
+@SET_MAKE@
+
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+VPATH = @srcdir@
+am__is_gnu_make = test -n '$(MAKEFILE_LIST)' && test -n '$(MAKELEVEL)'
+am__make_running_with_option = \
+  case $${target_option-} in \
+      ?) ;; \
+      *) echo "am__make_running_with_option: internal error: invalid" \
+              "target option '$${target_option-}' specified" >&2; \
+         exit 1;; \
+  esac; \
+  has_opt=no; \
+  sane_makeflags=$$MAKEFLAGS; \
+  if $(am__is_gnu_make); then \
+    sane_makeflags=$$MFLAGS; \
+  else \
+    case $$MAKEFLAGS in \
+      *\\[\ \	]*) \
+        bs=\\; \
+        sane_makeflags=`printf '%s\n' "$$MAKEFLAGS" \
+          | sed "s/$$bs$$bs[$$bs $$bs	]*//g"`;; \
+    esac; \
+  fi; \
+  skip_next=no; \
+  strip_trailopt () \
+  { \
+    flg=`printf '%s\n' "$$flg" | sed "s/$$1.*$$//"`; \
+  }; \
+  for flg in $$sane_makeflags; do \
+    test $$skip_next = yes && { skip_next=no; continue; }; \
+    case $$flg in \
+      *=*|--*) continue;; \
+        -*I) strip_trailopt 'I'; skip_next=yes;; \
+      -*I?*) strip_trailopt 'I';; \
+        -*O) strip_trailopt 'O'; skip_next=yes;; \
+      -*O?*) strip_trailopt 'O';; \
+        -*l) strip_trailopt 'l'; skip_next=yes;; \
+      -*l?*) strip_trailopt 'l';; \
+      -[dEDm]) skip_next=yes;; \
+      -[JT]) skip_next=yes;; \
+    esac; \
+    case $$flg in \
+      *$$target_option*) has_opt=yes; break;; \
+    esac; \
+  done; \
+  test $$has_opt = yes
+am__make_dryrun = (target_option=n; $(am__make_running_with_option))
+am__make_keepgoing = (target_option=k; $(am__make_running_with_option))
+pkgdatadir = $(datadir)/@PACKAGE@
+pkgincludedir = $(includedir)/@PACKAGE@
+pkglibdir = $(libdir)/@PACKAGE@
+pkglibexecdir = $(libexecdir)/@PACKAGE@
+am__cd = CDPATH="$${ZSH_VERSION+.}$(PATH_SEPARATOR)" && cd
+install_sh_DATA = $(install_sh) -c -m 644
+install_sh_PROGRAM = $(install_sh) -c
+install_sh_SCRIPT = $(install_sh) -c
+INSTALL_HEADER = $(INSTALL_DATA)
+transform = $(program_transform_name)
+NORMAL_INSTALL = :
+PRE_INSTALL = :
+POST_INSTALL = :
+NORMAL_UNINSTALL = :
+PRE_UNINSTALL = :
+POST_UNINSTALL = :
+build_triplet = @build@
+host_triplet = @host@
+subdir = libnetdata/procfile
+DIST_COMMON = $(srcdir)/Makefile.in $(srcdir)/Makefile.am \
+	$(dist_noinst_DATA)
+ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
+am__aclocal_m4_deps = $(top_srcdir)/build/m4/ax_c___atomic.m4 \
+	$(top_srcdir)/build/m4/ax_c__generic.m4 \
+	$(top_srcdir)/build/m4/ax_c_lto.m4 \
+	$(top_srcdir)/build/m4/ax_c_mallinfo.m4 \
+	$(top_srcdir)/build/m4/ax_c_mallopt.m4 \
+	$(top_srcdir)/build/m4/ax_check_compile_flag.m4 \
+	$(top_srcdir)/build/m4/ax_gcc_func_attribute.m4 \
+	$(top_srcdir)/build/m4/ax_pthread.m4 \
+	$(top_srcdir)/build/m4/jemalloc.m4 \
+	$(top_srcdir)/build/m4/tcmalloc.m4 $(top_srcdir)/configure.ac
+am__configure_deps = $(am__aclocal_m4_deps) $(CONFIGURE_DEPENDENCIES) \
+	$(ACLOCAL_M4)
+mkinstalldirs = $(install_sh) -d
+CONFIG_HEADER = $(top_builddir)/config.h
+CONFIG_CLEAN_FILES =
+CONFIG_CLEAN_VPATH_FILES =
+AM_V_P = $(am__v_P_@AM_V@)
+am__v_P_ = $(am__v_P_@AM_DEFAULT_V@)
+am__v_P_0 = false
+am__v_P_1 = :
+AM_V_GEN = $(am__v_GEN_@AM_V@)
+am__v_GEN_ = $(am__v_GEN_@AM_DEFAULT_V@)
+am__v_GEN_0 = @echo "  GEN     " $@;
+am__v_GEN_1 = 
+AM_V_at = $(am__v_at_@AM_V@)
+am__v_at_ = $(am__v_at_@AM_DEFAULT_V@)
+am__v_at_0 = @
+am__v_at_1 = 
+SOURCES =
+DIST_SOURCES =
+am__can_run_installinfo = \
+  case $$AM_UPDATE_INFO_DIR in \
+    n|no|NO) false;; \
+    *) (install-info --version) >/dev/null 2>&1;; \
+  esac
+DATA = $(dist_noinst_DATA)
+am__tagged_files = $(HEADERS) $(SOURCES) $(TAGS_FILES) $(LISP)
+DISTFILES = $(DIST_COMMON) $(DIST_SOURCES) $(TEXINFOS) $(EXTRA_DIST)
+ACLOCAL = @ACLOCAL@
+AMTAR = @AMTAR@
+AM_DEFAULT_VERBOSITY = @AM_DEFAULT_VERBOSITY@
+AUTOCONF = @AUTOCONF@
+AUTOHEADER = @AUTOHEADER@
+AUTOMAKE = @AUTOMAKE@
+AWK = @AWK@
+CC = @CC@
+CCDEPMODE = @CCDEPMODE@
+CFLAGS = @CFLAGS@
+CPP = @CPP@
+CPPFLAGS = @CPPFLAGS@
+CYGPATH_W = @CYGPATH_W@
+DEFS = @DEFS@
+DEPDIR = @DEPDIR@
+ECHO_C = @ECHO_C@
+ECHO_N = @ECHO_N@
+ECHO_T = @ECHO_T@
+EGREP = @EGREP@
+EXEEXT = @EXEEXT@
+GREP = @GREP@
+INSTALL = @INSTALL@
+INSTALL_DATA = @INSTALL_DATA@
+INSTALL_PROGRAM = @INSTALL_PROGRAM@
+INSTALL_SCRIPT = @INSTALL_SCRIPT@
+INSTALL_STRIP_PROGRAM = @INSTALL_STRIP_PROGRAM@
+IPMIMONITORING_CFLAGS = @IPMIMONITORING_CFLAGS@
+IPMIMONITORING_LIBS = @IPMIMONITORING_LIBS@
+LDFLAGS = @LDFLAGS@
+LIBCAP_CFLAGS = @LIBCAP_CFLAGS@
+LIBCAP_LIBS = @LIBCAP_LIBS@
+LIBMNL_CFLAGS = @LIBMNL_CFLAGS@
+LIBMNL_LIBS = @LIBMNL_LIBS@
+LIBOBJS = @LIBOBJS@
+LIBS = @LIBS@
+LTLIBOBJS = @LTLIBOBJS@
+MAINT = @MAINT@
+MAKEINFO = @MAKEINFO@
+MATH_CFLAGS = @MATH_CFLAGS@
+MATH_LIBS = @MATH_LIBS@
+MKDIR_P = @MKDIR_P@
+NFACCT_CFLAGS = @NFACCT_CFLAGS@
+NFACCT_LIBS = @NFACCT_LIBS@
+OBJEXT = @OBJEXT@
+OPTIONAL_IPMIMONITORING_CFLAGS = @OPTIONAL_IPMIMONITORING_CFLAGS@
+OPTIONAL_IPMIMONITORING_LIBS = @OPTIONAL_IPMIMONITORING_LIBS@
+OPTIONAL_LIBCAP_CFLAGS = @OPTIONAL_LIBCAP_CFLAGS@
+OPTIONAL_LIBCAP_LIBS = @OPTIONAL_LIBCAP_LIBS@
+OPTIONAL_MATH_CLFAGS = @OPTIONAL_MATH_CLFAGS@
+OPTIONAL_MATH_LIBS = @OPTIONAL_MATH_LIBS@
+OPTIONAL_NFACCT_CLFAGS = @OPTIONAL_NFACCT_CLFAGS@
+OPTIONAL_NFACCT_LIBS = @OPTIONAL_NFACCT_LIBS@
+OPTIONAL_UUID_CLFAGS = @OPTIONAL_UUID_CLFAGS@
+OPTIONAL_UUID_LIBS = @OPTIONAL_UUID_LIBS@
+OPTIONAL_ZLIB_CLFAGS = @OPTIONAL_ZLIB_CLFAGS@
+OPTIONAL_ZLIB_LIBS = @OPTIONAL_ZLIB_LIBS@
+PACKAGE = @PACKAGE@
+PACKAGE_BUGREPORT = @PACKAGE_BUGREPORT@
+PACKAGE_NAME = @PACKAGE_NAME@
+PACKAGE_RPM_RELEASE = @PACKAGE_RPM_RELEASE@
+PACKAGE_RPM_VERSION = @PACKAGE_RPM_VERSION@
+PACKAGE_STRING = @PACKAGE_STRING@
+PACKAGE_TARNAME = @PACKAGE_TARNAME@
+PACKAGE_URL = @PACKAGE_URL@
+PACKAGE_VERSION = @PACKAGE_VERSION@
+PATH_SEPARATOR = @PATH_SEPARATOR@
+PKG_CONFIG = @PKG_CONFIG@
+PKG_CONFIG_LIBDIR = @PKG_CONFIG_LIBDIR@
+PKG_CONFIG_PATH = @PKG_CONFIG_PATH@
+PTHREAD_CC = @PTHREAD_CC@
+PTHREAD_CFLAGS = @PTHREAD_CFLAGS@
+PTHREAD_LIBS = @PTHREAD_LIBS@
+SET_MAKE = @SET_MAKE@
+SHELL = @SHELL@
+SSE_CANDIDATE = @SSE_CANDIDATE@
+STRIP = @STRIP@
+UUID_CFLAGS = @UUID_CFLAGS@
+UUID_LIBS = @UUID_LIBS@
+VERSION = @VERSION@
+ZLIB_CFLAGS = @ZLIB_CFLAGS@
+ZLIB_LIBS = @ZLIB_LIBS@
+abs_builddir = @abs_builddir@
+abs_srcdir = @abs_srcdir@
+abs_top_builddir = @abs_top_builddir@
+abs_top_srcdir = @abs_top_srcdir@
+ac_ct_CC = @ac_ct_CC@
+am__include = @am__include@
+am__leading_dot = @am__leading_dot@
+am__quote = @am__quote@
+am__tar = @am__tar@
+am__untar = @am__untar@
+ax_pthread_config = @ax_pthread_config@
+bindir = @bindir@
+build = @build@
+build_alias = @build_alias@
+build_cpu = @build_cpu@
+build_os = @build_os@
+build_target = @build_target@
+build_vendor = @build_vendor@
+builddir = @builddir@
+cachedir = @cachedir@
+chartsdir = @chartsdir@
+configdir = @configdir@
+datadir = @datadir@
+datarootdir = @datarootdir@
+docdir = @docdir@
+dvidir = @dvidir@
+exec_prefix = @exec_prefix@
+has_jemalloc = @has_jemalloc@
+has_tcmalloc = @has_tcmalloc@
+host = @host@
+host_alias = @host_alias@
+host_cpu = @host_cpu@
+host_os = @host_os@
+host_vendor = @host_vendor@
+htmldir = @htmldir@
+includedir = @includedir@
+infodir = @infodir@
+install_sh = @install_sh@
+libconfigdir = @libconfigdir@
+libdir = @libdir@
+libexecdir = @libexecdir@
+localedir = @localedir@
+localstatedir = @localstatedir@
+logdir = @logdir@
+mandir = @mandir@
+mkdir_p = @mkdir_p@
+nodedir = @nodedir@
+oldincludedir = @oldincludedir@
+pdfdir = @pdfdir@
+pluginsdir = @pluginsdir@
+prefix = @prefix@
+program_transform_name = @program_transform_name@
+psdir = @psdir@
+pythondir = @pythondir@
+registrydir = @registrydir@
+sbindir = @sbindir@
+sharedstatedir = @sharedstatedir@
+srcdir = @srcdir@
+sysconfdir = @sysconfdir@
+target_alias = @target_alias@
+top_build_prefix = @top_build_prefix@
+top_builddir = @top_builddir@
+top_srcdir = @top_srcdir@
+varlibdir = @varlibdir@
+webdir = @webdir@
+AUTOMAKE_OPTIONS = subdir-objects
+MAINTAINERCLEANFILES = $(srcdir)/Makefile.in
+dist_noinst_DATA = \
+	README.md \
+	$(NULL)
+
+all: all-am
+
+.SUFFIXES:
+$(srcdir)/Makefile.in: @MAINTAINER_MODE_TRUE@ $(srcdir)/Makefile.am  $(am__configure_deps)
+	@for dep in $?; do \
+	  case '$(am__configure_deps)' in \
+	    *$$dep*) \
+	      ( cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) am--refresh ) \
+	        && { if test -f $@; then exit 0; else break; fi; }; \
+	      exit 1;; \
+	  esac; \
+	done; \
+	echo ' cd $(top_srcdir) && $(AUTOMAKE) --gnu libnetdata/procfile/Makefile'; \
+	$(am__cd) $(top_srcdir) && \
+	  $(AUTOMAKE) --gnu libnetdata/procfile/Makefile
+.PRECIOUS: Makefile
+Makefile: $(srcdir)/Makefile.in $(top_builddir)/config.status
+	@case '$?' in \
+	  *config.status*) \
+	    cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) am--refresh;; \
+	  *) \
+	    echo ' cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@ $(am__depfiles_maybe)'; \
+	    cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@ $(am__depfiles_maybe);; \
+	esac;
+
+$(top_builddir)/config.status: $(top_srcdir)/configure $(CONFIG_STATUS_DEPENDENCIES)
+	cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) am--refresh
+
+$(top_srcdir)/configure: @MAINTAINER_MODE_TRUE@ $(am__configure_deps)
+	cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) am--refresh
+$(ACLOCAL_M4): @MAINTAINER_MODE_TRUE@ $(am__aclocal_m4_deps)
+	cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) am--refresh
+$(am__aclocal_m4_deps):
+tags TAGS:
+
+ctags CTAGS:
+
+cscope cscopelist:
+
+
+distdir: $(DISTFILES)
+	@srcdirstrip=`echo "$(srcdir)" | sed 's/[].[^$$\\*]/\\\\&/g'`; \
+	topsrcdirstrip=`echo "$(top_srcdir)" | sed 's/[].[^$$\\*]/\\\\&/g'`; \
+	list='$(DISTFILES)'; \
+	  dist_files=`for file in $$list; do echo $$file; done | \
+	  sed -e "s|^$$srcdirstrip/||;t" \
+	      -e "s|^$$topsrcdirstrip/|$(top_builddir)/|;t"`; \
+	case $$dist_files in \
+	  */*) $(MKDIR_P) `echo "$$dist_files" | \
+			   sed '/\//!d;s|^|$(distdir)/|;s,/[^/]*$$,,' | \
+			   sort -u` ;; \
+	esac; \
+	for file in $$dist_files; do \
+	  if test -f $$file || test -d $$file; then d=.; else d=$(srcdir); fi; \
+	  if test -d $$d/$$file; then \
+	    dir=`echo "/$$file" | sed -e 's,/[^/]*$$,,'`; \
+	    if test -d "$(distdir)/$$file"; then \
+	      find "$(distdir)/$$file" -type d ! -perm -700 -exec chmod u+rwx {} \;; \
+	    fi; \
+	    if test -d $(srcdir)/$$file && test $$d != $(srcdir); then \
+	      cp -fpR $(srcdir)/$$file "$(distdir)$$dir" || exit 1; \
+	      find "$(distdir)/$$file" -type d ! -perm -700 -exec chmod u+rwx {} \;; \
+	    fi; \
+	    cp -fpR $$d/$$file "$(distdir)$$dir" || exit 1; \
+	  else \
+	    test -f "$(distdir)/$$file" \
+	    || cp -p $$d/$$file "$(distdir)/$$file" \
+	    || exit 1; \
+	  fi; \
+	done
+check-am: all-am
+check: check-am
+all-am: Makefile $(DATA)
+installdirs:
+install: install-am
+install-exec: install-exec-am
+install-data: install-data-am
+uninstall: uninstall-am
+
+install-am: all-am
+	@$(MAKE) $(AM_MAKEFLAGS) install-exec-am install-data-am
+
+installcheck: installcheck-am
+install-strip:
+	if test -z '$(STRIP)'; then \
+	  $(MAKE) $(AM_MAKEFLAGS) INSTALL_PROGRAM="$(INSTALL_STRIP_PROGRAM)" \
+	    install_sh_PROGRAM="$(INSTALL_STRIP_PROGRAM)" INSTALL_STRIP_FLAG=-s \
+	      install; \
+	else \
+	  $(MAKE) $(AM_MAKEFLAGS) INSTALL_PROGRAM="$(INSTALL_STRIP_PROGRAM)" \
+	    install_sh_PROGRAM="$(INSTALL_STRIP_PROGRAM)" INSTALL_STRIP_FLAG=-s \
+	    "INSTALL_PROGRAM_ENV=STRIPPROG='$(STRIP)'" install; \
+	fi
+mostlyclean-generic:
+
+clean-generic:
+
+distclean-generic:
+	-test -z "$(CONFIG_CLEAN_FILES)" || rm -f $(CONFIG_CLEAN_FILES)
+	-test . = "$(srcdir)" || test -z "$(CONFIG_CLEAN_VPATH_FILES)" || rm -f $(CONFIG_CLEAN_VPATH_FILES)
+
+maintainer-clean-generic:
+	@echo "This command is intended for maintainers to use"
+	@echo "it deletes files that may require special tools to rebuild."
+	-test -z "$(MAINTAINERCLEANFILES)" || rm -f $(MAINTAINERCLEANFILES)
+clean: clean-am
+
+clean-am: clean-generic mostlyclean-am
+
+distclean: distclean-am
+	-rm -f Makefile
+distclean-am: clean-am distclean-generic
+
+dvi: dvi-am
+
+dvi-am:
+
+html: html-am
+
+html-am:
+
+info: info-am
+
+info-am:
+
+install-data-am:
+
+install-dvi: install-dvi-am
+
+install-dvi-am:
+
+install-exec-am:
+
+install-html: install-html-am
+
+install-html-am:
+
+install-info: install-info-am
+
+install-info-am:
+
+install-man:
+
+install-pdf: install-pdf-am
+
+install-pdf-am:
+
+install-ps: install-ps-am
+
+install-ps-am:
+
+installcheck-am:
+
+maintainer-clean: maintainer-clean-am
+	-rm -f Makefile
+maintainer-clean-am: distclean-am maintainer-clean-generic
+
+mostlyclean: mostlyclean-am
+
+mostlyclean-am: mostlyclean-generic
+
+pdf: pdf-am
+
+pdf-am:
+
+ps: ps-am
+
+ps-am:
+
+uninstall-am:
+
+.MAKE: install-am install-strip
+
+.PHONY: all all-am check check-am clean clean-generic cscopelist-am \
+	ctags-am distclean distclean-generic distdir dvi dvi-am html \
+	html-am info info-am install install-am install-data \
+	install-data-am install-dvi install-dvi-am install-exec \
+	install-exec-am install-html install-html-am install-info \
+	install-info-am install-man install-pdf install-pdf-am \
+	install-ps install-ps-am install-strip installcheck \
+	installcheck-am installdirs maintainer-clean \
+	maintainer-clean-generic mostlyclean mostlyclean-generic pdf \
+	pdf-am ps ps-am tags-am uninstall uninstall-am
+
+
+# Tell versions [3.59,3.63) of GNU make to not export all variables.
+# Otherwise a system limit (for SysV at least) may be exceeded.
+.NOEXPORT:
diff --git a/libnetdata/procfile/README.md b/libnetdata/procfile/README.md
new file mode 100644
index 00000000..279885f9
--- /dev/null
+++ b/libnetdata/procfile/README.md
@@ -0,0 +1,61 @@
+
+# PROCFILE
+
+procfile is a library for reading text data files (i.e `/proc` files) in the fastest possible way.
+
+## How it works
+
+The library automatically adapts (through the iterations) its memory so that each file
+is read with single `read()` call.
+
+Then the library splits the file into words, using the supplied separators.
+The library also supported quoted words (i.e. strings within of which the separators are ignored).
+
+### Initialization
+
+Initially the caller: 
+
+- calls `procfile_open()` to open the file and allocate the structures needed.
+
+### Iterations
+
+For each iteration, the caller:
+
+- calls `procfile_readall()` to read updated contents.
+   This call also rewinds (`lseek()` to 0) before reading it.
+
+   For every file, a [BUFFER](../buffer/) is used that is automatically adjusted to fit
+   the entire file contents of the file. So the file is read with a single `read()` call
+   (providing atomicity / consistency when the data are read from the kernel).
+
+   Once the data are read, 2 arrays of pointers are updated:
+
+   - a `words` array, pointing to each word in the data read
+   - a `lines` array, pointing to the first word for each line
+
+   This is highly optimized. Both arrays are automatically adjusted to
+   fit all contents and are updated in a single pass on the data.
+   
+   The library provides a number of macros:
+   
+   - `procfile_lines()` returns the # of lines read
+   - `procfile_linewords()` returns the # of words in the given line
+   - `procfile_word()` returns a pointer the given word #
+   - `procfile_line()` returns a pointer to the first word of the given line #
+   - `procfile_lineword()` returns a pointer to the given word # of the given line #
+
+### Cleanup
+
+When the caller exits:
+
+- calls `procfile_free()` to close the file and free all memory used.
+
+### Performance
+
+- a **raspberry Pi 1** (the oldest single core one) can process 5.000+ `/proc` files per second.
+- a **J1900 Celeron** processor can process 23.000+ `/proc` files per second per core.
+
+To achieve this kind of performance, the library tries to work in batches so that the code
+and the data are inside the processor's caches.
+
+This library is extensively used in netdata and its plugins.
diff --git a/src/procfile.c b/libnetdata/procfile/procfile.c
index 044f975b..4a812baa 100644
--- a/src/procfile.c
+++ b/libnetdata/procfile/procfile.c
@@ -1,5 +1,6 @@
-#include "common.h"
-#include "procfile.h"
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "../libnetdata.h"
 
 #define PF_PREFIX "PROCFILE"
 
@@ -7,6 +8,8 @@
 #define PFLINES_INCREASE_STEP 10
 #define PROCFILE_INCREMENT_BUFFER 512
 
+int procfile_open_flags = O_RDONLY;
+
 int procfile_adaptive_initial_allocation = 0;
 
 // if adaptive allocation is set, these store the
@@ -391,7 +394,7 @@ void procfile_set_open_close(procfile *ff, const char *open, const char *close)
 procfile *procfile_open(const char *filename, const char *separators, uint32_t flags) {
     debug(D_PROCFILE, PF_PREFIX ": Opening file '%s'", filename);
 
-    int fd = open(filename, O_RDONLY, 0666);
+    int fd = open(filename, procfile_open_flags, 0666);
     if(unlikely(fd == -1)) {
         if(unlikely(!(flags & PROCFILE_FLAG_NO_ERROR_ON_FILE_IO))) error(PF_PREFIX ": Cannot open file '%s'", filename);
         return NULL;
@@ -427,7 +430,7 @@ procfile *procfile_reopen(procfile *ff, const char *filename, const char *separa
         close(ff->fd);
     }
 
-    ff->fd = open(filename, O_RDONLY, 0666);
+    ff->fd = open(filename, procfile_open_flags, 0666);
     if(unlikely(ff->fd == -1)) {
         procfile_close(ff);
         return NULL;
@@ -451,6 +454,7 @@ procfile *procfile_reopen(procfile *ff, const char *filename, const char *separa
 void procfile_print(procfile *ff) {
     size_t lines = procfile_lines(ff), l;
     char *s;
+    (void)s;
 
     debug(D_PROCFILE, "File '%s' with %zu lines and %zu words", procfile_filename(ff), ff->lines->len, ff->words->len);
 
diff --git a/src/procfile.h b/libnetdata/procfile/procfile.h
index 012c6efe..b107358a 100644
--- a/src/procfile.h
+++ b/libnetdata/procfile/procfile.h
@@ -1,31 +1,10 @@
-/*
- * procfile is a library for reading kernel files from /proc
- *
- * The idea is this:
- *
- *  - every file is opened once with procfile_open().
- *
- *  - to read updated contents, we rewind it (lseek() to 0) and read again
- *    with procfile_readall().
- *
- *  - for every file, we use a buffer that is adjusted to fit its entire
- *    contents in memory, allowing us to read it with a single read() call.
- *    (this provides atomicity / consistency on the data read from the kernel)
- *
- *  - once the data are read, we update two arrays of pointers:
- *     - a words array, pointing to each word in the data read
- *     - a lines array, pointing to the first word for each line
- *
- *    This is highly optimized. Both arrays are automatically adjusted to
- *    fit all contents and are updated in a single pass on the data:
- *     - a raspberry Pi can process 5.000+ files / sec.
- *     - a J1900 celeron processor can process 23.000+ files / sec.
-*/
-
+// SPDX-License-Identifier: GPL-3.0-or-later
 
 #ifndef NETDATA_PROCFILE_H
 #define NETDATA_PROCFILE_H 1
 
+#include "../libnetdata.h"
+
 // ----------------------------------------------------------------------------
 // An array of words
 
@@ -103,6 +82,9 @@ extern char *procfile_filename(procfile *ff);
 
 // ----------------------------------------------------------------------------
 
+// set to the O_XXXX flags, to have procfile_open and procfile_reopen use them when opening proc files
+extern int procfile_open_flags;
+
 // set this to 1, to have procfile adapt its initial buffer allocation to the max allocation used so far
 extern int procfile_adaptive_initial_allocation;