checkrt tool rewritten

.gitignore

@@ -0,0 +1,11 @@
+*.o
+*.so
+*.gz
+
+src/*_test
+src/checkrt
+src/res.h
+
+src/cxx/
+src/gcc/
+

AppRun

@@ -0,0 +1,24 @@
+#!/bin/sh -e
+
+# add your command to execute here
+exec=
+
+cd "$(dirname "$0")"
+if [ "x$exec" = "x" ]; then
+  exec="$(sed -n 's|^Exec=||p' *.desktop | head -1)"
+fi
+if [ -x "./usr/optional/checkrt" ]; then
+  extra_libs="$(./usr/optional/checkrt)"
+fi
+if [ -n "$extra_libs" ]; then
+  export LD_LIBRARY_PATH="${extra_libs}${LD_LIBRARY_PATH}"
+  if [ -e "$PWD/usr/optional/exec.so" ]; then
+    export LD_PRELOAD="$PWD/usr/optional/exec.so:${LD_PRELOAD}"
+  fi
+fi
+
+#echo ">>>>> $LD_LIBRARY_PATH"
+#echo ">>>>> $LD_PRELOAD"
+
+./usr/bin/$exec "$*"
+exit $?

COPYING

@@ -0,0 +1,23 @@
+checkrt.c: 2022 <djcj@gmx.de>
+env.c exec.c: 2018 Pablo Marcos Oltra <pablo.marcos.oltra@gmail.com>
+
+The MIT License
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+

README.md

@@ -0,0 +1,56 @@
+# The problem
+
+Some projects require newer C++ standards to build them. To keep the glibc
+dependency low you can build a newer GCC version on an older distro and use it
+to compile the project. This project however will now require a newer version of
+the `libstdc++.so.6` library than available on that distro.
+Blindly bundling `libstdc++.so.6` however will in most cases break compatibility
+with distros that have a newer library version installed into their system than
+the bundled one.
+
+By the way, while this is primarily an issue with `libstdc++.so.6` in some cases
+this might also occur with `libgcc_s.so.1`. That's because both libraries are
+part of GCC.
+
+
+# The solution
+
+You would have to know the library version of the host system and decide whether
+to use a bundled library or not before the application is started. This is
+exactly what the `checkrt` tool does. It will search for a bundled `libstdc++.so.6`
+and `libgcc_s.so.1` library inside the AppImage or AppDir. If found it will
+compare their internal versions with the ones found on the system (using dlopen())
+and prepend their paths to `LD_LIBRARY_PATH` if necessary.
+
+
+# Usage
+
+Compile with `make -C src`. Inside your AppDir create the directory `usr/optional/`
+and put the binary `checkrt` inside there. Execute `usr/optional/checkrt --copy-libraries`
+to bundle your system's `libstdc++.so.6` and `libgcc_s.so.1` libraries.
+Use the provided AppRun script or write/modify your own. `checkrt` will either
+return a path that can be added to `LD_LIBRARY_PATH` or an empty string.
+Error messages, help and verbosity will always be returned to stderr.
+
+
+# exec.so
+
+You might also want to bundle `exec.so` inside `usr/optional/`. This library is
+intended to restore the environment of the AppImage to its parent. This is done
+to avoid library clashing of bundled libraries with external processes, e.g. when
+running the web browser.
+
+The intended usage is as follows:
+
+1. This library is injected to the dynamic loader through LD_PRELOAD
+   automatically in AppRun **only** if `usr/optional/exec.so` exists: 
+   e.g `LD_PRELOAD=$APPDIR/usr/optional/exec.so My.AppImage`
+
+2. This library will intercept calls to new processes and will detect whether
+   those calls are for binaries within the AppImage bundle or external ones.
+
+3. In case it's an internal process, it will not change anything.
+   In case it's an external process, it will restore the environment of
+   the AppImage parent by reading `/proc/[pid]/environ`.
+   This is the conservative approach taken.
+

src/COPYING.RUNTIME

@@ -0,0 +1,73 @@
+GCC RUNTIME LIBRARY EXCEPTION
+
+Version 3.1, 31 March 2009
+
+Copyright (C) 2009 Free Software Foundation, Inc. <http://fsf.org/>
+
+Everyone is permitted to copy and distribute verbatim copies of this
+license document, but changing it is not allowed.
+
+This GCC Runtime Library Exception ("Exception") is an additional
+permission under section 7 of the GNU General Public License, version
+3 ("GPLv3"). It applies to a given file (the "Runtime Library") that
+bears a notice placed by the copyright holder of the file stating that
+the file is governed by GPLv3 along with this Exception.
+
+When you use GCC to compile a program, GCC may combine portions of
+certain GCC header files and runtime libraries with the compiled
+program. The purpose of this Exception is to allow compilation of
+non-GPL (including proprietary) programs to use, in this way, the
+header files and runtime libraries covered by this Exception.
+
+0. Definitions.
+
+A file is an "Independent Module" if it either requires the Runtime
+Library for execution after a Compilation Process, or makes use of an
+interface provided by the Runtime Library, but is not otherwise based
+on the Runtime Library.
+
+"GCC" means a version of the GNU Compiler Collection, with or without
+modifications, governed by version 3 (or a specified later version) of
+the GNU General Public License (GPL) with the option of using any
+subsequent versions published by the FSF.
+
+"GPL-compatible Software" is software whose conditions of propagation,
+modification and use would permit combination with GCC in accord with
+the license of GCC.
+
+"Target Code" refers to output from any compiler for a real or virtual
+target processor architecture, in executable form or suitable for
+input to an assembler, loader, linker and/or execution
+phase. Notwithstanding that, Target Code does not include data in any
+format that is used as a compiler intermediate representation, or used
+for producing a compiler intermediate representation.
+
+The "Compilation Process" transforms code entirely represented in
+non-intermediate languages designed for human-written code, and/or in
+Java Virtual Machine byte code, into Target Code. Thus, for example,
+use of source code generators and preprocessors need not be considered
+part of the Compilation Process, since the Compilation Process can be
+understood as starting with the output of the generators or
+preprocessors.
+
+A Compilation Process is "Eligible" if it is done using GCC, alone or
+with other GPL-compatible software, or if it is done without using any
+work based on GCC. For example, using non-GPL-compatible Software to
+optimize any GCC intermediate representations would not qualify as an
+Eligible Compilation Process.
+
+1. Grant of Additional Permission.
+
+You have permission to propagate a work of Target Code formed by
+combining the Runtime Library with Independent Modules, even if such
+propagation would otherwise violate the terms of GPLv3, provided that
+all Target Code was generated by Eligible Compilation Processes. You
+may then convey such a combination under terms of your choice,
+consistent with the licensing of the Independent Modules.
+
+2. No Weakening of GCC Copyleft.
+
+The availability of this Exception does not imply any general
+presumption that third-party software is unaffected by the copyleft
+requirements of the license of GCC.
+

src/COPYING.libgcc

@@ -0,0 +1,23 @@
+Copyright (C) 1989-2022 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it 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.
+
+Under Section 7 of GPL version 3, you are granted additional
+permissions described in the GCC Runtime Library Exception, version
+3.1, as published by the Free Software Foundation.
+
+You should have received a copy of the GNU General Public License and
+a copy of the GCC Runtime Library Exception along with this program;
+see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+<http://www.gnu.org/licenses/>.
+

src/COPYING.libstdc++

@@ -0,0 +1,22 @@
+Copyright (C) 1997-2022 Free Software Foundation, Inc.
+
+This file is part of the GNU ISO C++ Library.  This library is free
+software; you can redistribute it and/or modify it under the
+terms of the GNU General Public License as published by the
+Free Software Foundation; either version 3, or (at your option)
+any later version.
+
+This library is distributed in the hope that it 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.
+
+Under Section 7 of GPL version 3, you are granted additional
+permissions described in the GCC Runtime Library Exception, version
+3.1, as published by the Free Software Foundation.
+
+You should have received a copy of the GNU General Public License and
+a copy of the GCC Runtime Library Exception along with this program;
+see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+<http://www.gnu.org/licenses/>.
+

src/COPYING3

@@ -0,0 +1,674 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
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+
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+    any liability that these contractual assumptions directly impose on
+    those licensors and authors.
+
+  All other non-permissive additional terms are considered "further
+restrictions" within the meaning of section 10.  If the Program as you
+received it, or any part of it, contains a notice stating that it is
+governed by this License along with a term that is a further
+restriction, you may remove that term.  If a license document contains
+a further restriction but permits relicensing or conveying under this
+License, you may add to a covered work material governed by the terms
+of that license document, provided that the further restriction does
+not survive such relicensing or conveying.
+
+  If you add terms to a covered work in accord with this section, you
+must place, in the relevant source files, a statement of the
+additional terms that apply to those files, or a notice indicating
+where to find the applicable terms.
+
+  Additional terms, permissive or non-permissive, may be stated in the
+form of a separately written license, or stated as exceptions;
+the above requirements apply either way.
+
+  8. Termination.
+
+  You may not propagate or modify a covered work except as expressly
+provided under this License.  Any attempt otherwise to propagate or
+modify it is void, and will automatically terminate your rights under
+this License (including any patent licenses granted under the third
+paragraph of section 11).
+
+  However, if you cease all violation of this License, then your
+license from a particular copyright holder is reinstated (a)
+provisionally, unless and until the copyright holder explicitly and
+finally terminates your license, and (b) permanently, if the copyright
+holder fails to notify you of the violation by some reasonable means
+prior to 60 days after the cessation.
+
+  Moreover, your license from a particular copyright holder is
+reinstated permanently if the copyright holder notifies you of the
+violation by some reasonable means, this is the first time you have
+received notice of violation of this License (for any work) from that
+copyright holder, and you cure the violation prior to 30 days after
+your receipt of the notice.
+
+  Termination of your rights under this section does not terminate the
+licenses of parties who have received copies or rights from you under
+this License.  If your rights have been terminated and not permanently
+reinstated, you do not qualify to receive new licenses for the same
+material under section 10.
+
+  9. Acceptance Not Required for Having Copies.
+
+  You are not required to accept this License in order to receive or
+run a copy of the Program.  Ancillary propagation of a covered work
+occurring solely as a consequence of using peer-to-peer transmission
+to receive a copy likewise does not require acceptance.  However,
+nothing other than this License grants you permission to propagate or
+modify any covered work.  These actions infringe copyright if you do
+not accept this License.  Therefore, by modifying or propagating a
+covered work, you indicate your acceptance of this License to do so.
+
+  10. Automatic Licensing of Downstream Recipients.
+
+  Each time you convey a covered work, the recipient automatically
+receives a license from the original licensors, to run, modify and
+propagate that work, subject to this License.  You are not responsible
+for enforcing compliance by third parties with this License.
+
+  An "entity transaction" is a transaction transferring control of an
+organization, or substantially all assets of one, or subdividing an
+organization, or merging organizations.  If propagation of a covered
+work results from an entity transaction, each party to that
+transaction who receives a copy of the work also receives whatever
+licenses to the work the party's predecessor in interest had or could
+give under the previous paragraph, plus a right to possession of the
+Corresponding Source of the work from the predecessor in interest, if
+the predecessor has it or can get it with reasonable efforts.
+
+  You may not impose any further restrictions on the exercise of the
+rights granted or affirmed under this License.  For example, you may
+not impose a license fee, royalty, or other charge for exercise of
+rights granted under this License, and you may not initiate litigation
+(including a cross-claim or counterclaim in a lawsuit) alleging that
+any patent claim is infringed by making, using, selling, offering for
+sale, or importing the Program or any portion of it.
+
+  11. Patents.
+
+  A "contributor" is a copyright holder who authorizes use under this
+License of the Program or a work on which the Program is based.  The
+work thus licensed is called the contributor's "contributor version".
+
+  A contributor's "essential patent claims" are all patent claims
+owned or controlled by the contributor, whether already acquired or
+hereafter acquired, that would be infringed by some manner, permitted
+by this License, of making, using, or selling its contributor version,
+but do not include claims that would be infringed only as a
+consequence of further modification of the contributor version.  For
+purposes of this definition, "control" includes the right to grant
+patent sublicenses in a manner consistent with the requirements of
+this License.
+
+  Each contributor grants you a non-exclusive, worldwide, royalty-free
+patent license under the contributor's essential patent claims, to
+make, use, sell, offer for sale, import and otherwise run, modify and
+propagate the contents of its contributor version.
+
+  In the following three paragraphs, a "patent license" is any express
+agreement or commitment, however denominated, not to enforce a patent
+(such as an express permission to practice a patent or covenant not to
+sue for patent infringement).  To "grant" such a patent license to a
+party means to make such an agreement or commitment not to enforce a
+patent against the party.
+
+  If you convey a covered work, knowingly relying on a patent license,
+and the Corresponding Source of the work is not available for anyone
+to copy, free of charge and under the terms of this License, through a
+publicly available network server or other readily accessible means,
+then you must either (1) cause the Corresponding Source to be so
+available, or (2) arrange to deprive yourself of the benefit of the
+patent license for this particular work, or (3) arrange, in a manner
+consistent with the requirements of this License, to extend the patent
+license to downstream recipients.  "Knowingly relying" means you have
+actual knowledge that, but for the patent license, your conveying the
+covered work in a country, or your recipient's use of the covered work
+in a country, would infringe one or more identifiable patents in that
+country that you have reason to believe are valid.
+
+  If, pursuant to or in connection with a single transaction or
+arrangement, you convey, or propagate by procuring conveyance of, a
+covered work, and grant a patent license to some of the parties
+receiving the covered work authorizing them to use, propagate, modify
+or convey a specific copy of the covered work, then the patent license
+you grant is automatically extended to all recipients of the covered
+work and works based on it.
+
+  A patent license is "discriminatory" if it does not include within
+the scope of its coverage, prohibits the exercise of, or is
+conditioned on the non-exercise of one or more of the rights that are
+specifically granted under this License.  You may not convey a covered
+work if you are a party to an arrangement with a third party that is
+in the business of distributing software, under which you make payment
+to the third party based on the extent of your activity of conveying
+the work, and under which the third party grants, to any of the
+parties who would receive the covered work from you, a discriminatory
+patent license (a) in connection with copies of the covered work
+conveyed by you (or copies made from those copies), or (b) primarily
+for and in connection with specific products or compilations that
+contain the covered work, unless you entered into that arrangement,
+or that patent license was granted, prior to 28 March 2007.
+
+  Nothing in this License shall be construed as excluding or limiting
+any implied license or other defenses to infringement that may
+otherwise be available to you under applicable patent law.
+
+  12. No Surrender of Others' Freedom.
+
+  If conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot convey a
+covered work so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you may
+not convey it at all.  For example, if you agree to terms that obligate you
+to collect a royalty for further conveying from those to whom you convey
+the Program, the only way you could satisfy both those terms and this
+License would be to refrain entirely from conveying the Program.
+
+  13. Use with the GNU Affero General Public License.
+
+  Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU Affero General Public License into a single
+combined work, and to convey the resulting work.  The terms of this
+License will continue to apply to the part which is the covered work,
+but the special requirements of the GNU Affero General Public License,
+section 13, concerning interaction through a network will apply to the
+combination as such.
+
+  14. Revised Versions of this License.
+
+  The Free Software Foundation may publish revised and/or new versions of
+the GNU General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+  Each version is given a distinguishing version number.  If the
+Program specifies that a certain numbered version of the GNU General
+Public License "or any later version" applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation.  If the Program does not specify a version number of the
+GNU General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+  If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+  Later license versions may give you additional or different
+permissions.  However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+  15. Disclaimer of Warranty.
+
+  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it 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.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<http://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<http://www.gnu.org/philosophy/why-not-lgpl.html>.

src/Makefile

@@ -0,0 +1,51 @@
+BIN = checkrt
+LIB = exec.so
+EXEC_TEST = exec_test
+ENV_TEST = env_test
+CHECKRT_TEST = checkrt_test
+
+CFLAGS := -Wall -O3
+LDFLAGS := -s
+
+
+all: $(BIN) $(LIB)
+
+clean:
+	-rm -f *.o *.gz res.h $(BIN) $(LIB) $(EXEC_TEST) $(ENV_TEST) $(CHECKRT_TEST)
+
+distclean: clean
+	-rm -rf cxx gcc
+
+$(BIN): checkrt.o
+	$(CC) -o $@ $^ $(LDFLAGS) -ldl
+
+checkrt.c: res.h
+
+res.h:
+	gzip -k -f COPYING.RUNTIME COPYING3 && \
+  xxd -i COPYING.RUNTIME.gz > $@ && \
+  xxd -i COPYING3.gz >> $@ && \
+  xxd -i COPYING.libgcc >> $@ && \
+  xxd -i COPYING.libstdc++ >> $@
+
+exec.o env.o: CFLAGS += -fPIC
+
+$(LIB): exec.o env.o
+	$(CC) -o $@ $^ -shared $(LDFLAGS) -ldl
+
+$(CHECKRT_TEST): checkrt.c
+	$(CC) -o $@ $(CFLAGS) -DCHECKRT_TEST $^ -ldl
+
+$(EXEC_TEST): exec.c env.o
+	$(CC) -o $@ $(CFLAGS) -DEXEC_TEST $^ -ldl
+
+$(ENV_TEST): env.c
+	$(CC) -o $@ $(CFLAGS) -DENV_TEST $^
+
+run_tests: $(EXEC_TEST) $(ENV_TEST) $(CHECKRT_TEST)
+	./$(ENV_TEST)
+	./$(EXEC_TEST)
+	./$(CHECKRT_TEST)
+
+.PHONY: $(BIN) all clean
+

src/checkrt.c

@@ -0,0 +1,392 @@
+/* Copyright (c) 2022 <djcj@gmx.de>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+#include <link.h>
+#include <dlfcn.h>
+#include <elf.h>
+#include <fcntl.h>
+#include <libgen.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include "res.h"
+
+#ifdef __x86_64__
+  typedef Elf64_Ehdr  Elf_Ehdr;
+  typedef Elf64_Shdr  Elf_Shdr;
+  typedef Elf64_Sym   Elf_Sym;
+#else
+  typedef Elf32_Ehdr  Elf_Ehdr;
+  typedef Elf32_Shdr  Elf_Shdr;
+  typedef Elf32_Sym   Elf_Sym;
+#endif
+
+#define LIBGCC_S_SO  "libgcc_s.so.1"
+#define LIBSTDCXX_SO "libstdc++.so.6"
+#define LIBGCC_DIR   "gcc"
+#define STDCXX_DIR   "cxx"
+
+#define MAX(X,Y)  (((X) > (Y)) ? (X) : (Y))
+#define PRINT_VERBOSE(FMT, ...)  if (verbose) { fprintf(stderr, FMT, __VA_ARGS__); }
+
+
+static char *get_libname(const char *lib, char verbose)
+{
+  struct link_map *map = NULL;
+  char *path;
+
+  void *handle = dlopen(lib, RTLD_LAZY);
+  if (!handle) {
+    PRINT_VERBOSE("error: failed to dlopen() file: %s\n", lib);
+    return NULL;
+  }
+
+  if (dlinfo(handle, RTLD_DI_LINKMAP, &map) == -1) {
+    PRINT_VERBOSE("error: could not retrieve information: %s\n", lib);
+    dlclose(handle);
+    return NULL;
+  }
+
+  path = strdup(map->l_name);
+  dlclose(handle);
+
+  return path;
+}
+
+static int symbol_version(const char *lib, const char *symbol, char verbose)
+{
+  int fd = -1;
+  void *addr = NULL;
+  const char *error = "";
+
+  /* let dlopen() do all the compatibility checks */
+  char *orig = get_libname(lib, verbose);
+  if (!orig) return -1;
+
+  fd = open(orig, O_RDONLY);
+  if (fd < 0) {
+    PRINT_VERBOSE("error: failed to open() file: %s\n", orig);
+    free(orig);
+    return -1;
+  }
+
+  PRINT_VERBOSE("%s\n", orig);
+  free(orig);
+
+  /* make sure file size is larger than the required ELF header size */
+  struct stat st;
+  if (fstat(fd, &st) < 0 || st.st_size < sizeof(Elf_Ehdr)) {
+    error = "fstat() failed or returned a too low file size";
+    goto symbol_version_error;
+  }
+
+  /* mmap() library */
+  addr = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
+  if (addr == MAP_FAILED) {
+    error = "mmap() failed";
+    goto symbol_version_error;
+  }
+
+  /* ELF header */
+  Elf_Ehdr *ehdr = addr;
+  error = "offset exceeding filesize";
+  if (ehdr->e_shoff > st.st_size) {
+    goto symbol_version_error;
+  }
+
+  Elf_Shdr *shdr = addr + ehdr->e_shoff;
+  int shnum = ehdr->e_shnum;
+  Elf_Shdr *sh_strtab = &shdr[ehdr->e_shstrndx];
+
+  if (sh_strtab->sh_offset > st.st_size) {
+    goto symbol_version_error;
+  }
+  const char *sh_strtab_p = addr + sh_strtab->sh_offset;
+  const char *sh_dynstr_p = sh_strtab_p;
+  const char * const sh_strtab_p_const = sh_strtab_p;
+
+  /* get strtab/dynstr */
+  for (int i = 0; i < shnum; ++i) {
+    if (shdr[i].sh_type != SHT_STRTAB) continue;
+    const char *name = sh_strtab_p_const + shdr[i].sh_name;
+
+    if (strcmp(name, ".strtab") == 0) {
+      if (shdr[i].sh_offset > st.st_size) {
+        goto symbol_version_error;
+      }
+      sh_strtab_p = addr + shdr[i].sh_offset;
+      break;
+    } else if (strcmp(name, ".dynstr") == 0) {
+      if (shdr[i].sh_offset > st.st_size) {
+        goto symbol_version_error;
+      }
+      sh_dynstr_p = addr + shdr[i].sh_offset;
+      break;
+    }
+  }
+
+  /* iterate through sections */
+  size_t len = strlen(symbol);
+  int maj = 0, min = 0, pat = 0;
+  for (int i = 0; i < shnum; ++i) {
+    if (shdr[i].sh_type != SHT_SYMTAB && shdr[i].sh_type != SHT_DYNSYM) {
+      continue;
+    }
+
+    if (shdr[i].sh_offset > st.st_size) {
+      goto symbol_version_error;
+    }
+    Elf_Sym *syms_data = addr + shdr[i].sh_offset;
+
+    /* iterate through symbols */
+    for (size_t j = 0; j < shdr[i].sh_size / sizeof(Elf_Sym); ++j) {
+      if (syms_data[j].st_shndx != SHN_ABS) {
+        continue;
+      }
+
+      const char *symbol_name;
+      if (shdr[i].sh_type == SHT_DYNSYM) {
+        symbol_name = sh_dynstr_p + syms_data[j].st_name;
+      } else {
+        symbol_name = sh_strtab_p + syms_data[j].st_name;
+      }
+
+      if (strncmp(symbol_name, symbol, len) != 0) {
+        continue;
+      }
+
+      int tmp_maj = 0, tmp_min = 0, tmp_pat = 0;
+      if (sscanf(symbol_name + len, "%d.%d.%d", &tmp_maj, &tmp_min, &tmp_pat) < 1) {
+        continue;
+      }
+
+      if (tmp_maj < maj) {
+        continue;
+      } else if (tmp_maj > maj) {
+        maj = tmp_maj;
+        min = tmp_min;
+        pat = tmp_pat;
+        continue;
+      }
+
+      if (tmp_min < min) {
+        continue;
+      } else if (tmp_min > min) {
+        min = tmp_min;
+        pat = tmp_pat;
+        continue;
+      }
+
+      if (tmp_pat > pat) {
+        pat = tmp_pat;
+      }
+    }
+  }
+
+  PRINT_VERBOSE("%s%d.%d.%d\n", symbol, maj, min, pat);
+  munmap(addr, st.st_size);
+  close(fd);
+  return (pat + min*1000 + maj*1000000);
+
+symbol_version_error:
+  PRINT_VERBOSE("error: %s: %s\n", error, orig);
+  munmap(addr, st.st_size);
+  close(fd);
+  return -1;
+}
+
+static void dump_file(const char *dest, unsigned char *data, unsigned int len)
+{
+  int fd = creat(dest, DEFFILEMODE);
+  if (fd == -1) return;
+  if (write(fd, data, len) != len) unlink(dest);
+  close(fd);
+}
+
+static int copy_lib(const char *lib, const char *destDir, char verbose)
+{
+  char *destFull = NULL;
+  int fdIn = -1, fdOut = -1;
+
+  /* get full source and target paths */
+  char *srcFull = get_libname(lib, verbose);
+  if (!srcFull) goto copy_lib_error;
+
+  char *base = basename(srcFull);
+  if (!base) goto copy_lib_error;
+
+  size_t len = strlen(destDir);
+  size_t len2 = strlen(base);
+  destFull = malloc(len + MAX(len2,32) + 2);
+  sprintf(destFull, "%s/%s", destDir, base);
+
+  /* open source for reading */
+  fdIn = open(srcFull, O_RDONLY|O_CLOEXEC);
+  if (fdIn == -1) goto copy_lib_error;
+
+  /* open target for writing */
+  mkdir(destDir, ACCESSPERMS);
+  fdOut = creat(destFull, DEFFILEMODE);
+  if (fdOut == -1) goto copy_lib_error;
+
+  /* copy data into target */
+  ssize_t n;
+  unsigned char buf[512*1024];
+  while ((n = read(fdIn, &buf, sizeof(buf))) > 0) {
+    if (write(fdOut, &buf, n) != n) {
+      goto copy_lib_error;
+    }
+  }
+
+  int rv = 0;
+  fprintf(stderr, ">> %s\ncopied to -> %s\n", srcFull, destFull);
+
+  /* dump COPYING files */
+  char *p = destFull + len + 1;
+  strcpy(p, "COPYING.RUNTIME.gz");
+  dump_file(destFull, COPYING_RUNTIME_gz, COPYING_RUNTIME_gz_len);
+  p += 7;
+  strcpy(p, "3.gz");
+  dump_file(destFull, COPYING3_gz, COPYING3_gz_len);
+  strcpy(p, ".libgcc");
+  dump_file(destFull, COPYING_libgcc, COPYING_libgcc_len);
+  strcpy(p, ".libstdc++");
+  dump_file(destFull, COPYING_libstdc__, COPYING_libstdc___len);
+  fprintf(stderr, "(COPYING files were added too)\n");
+
+  goto copy_lib_end;
+
+copy_lib_error:
+  rv = -1;
+
+copy_lib_end:
+  if (fdOut != -1) close(fdOut);
+  if (fdIn != -1) close(fdIn);
+  if (srcFull) free(srcFull);
+  if (destFull) free(destFull);
+
+  return rv;
+}
+
+
+int main(int argc, char **argv)
+{
+#if CHECKRT_TEST == 1
+
+  printf("Test:\n");
+  copy_lib(LIBGCC_S_SO, "./" LIBGCC_DIR, 1);
+  copy_lib(LIBSTDCXX_SO, "./" STDCXX_DIR, 1);
+  symbol_version(LIBGCC_S_SO, "GCC_", 1);
+  symbol_version(LIBSTDCXX_SO, "GLIBCXX_", 1);
+  symbol_version("./" LIBGCC_DIR "/" LIBGCC_S_SO, "GCC_", 1);
+  symbol_version("./" STDCXX_DIR "/" LIBSTDCXX_SO, "GLIBCXX_", 1);
+
+#else
+
+  char v = 0, copy = 0;
+
+  for (int i=1; i < argc; i++) {
+    if (strcmp(argv[i], "-h") == 0 || strcmp(argv[i], "--help") == 0) {
+      fprintf(stderr,
+        "usage:\n"
+        "  %s -c|--copy-libraries\n"
+        "  %s -h|--help\n"
+        "  %s -v|--verbose\n"
+        "\n"
+        "This program will look for the following libraries relative to its\n"
+        "location, check if they are usable and add them to LD_LIBRARY_PATH\n"
+        "if they are newer than the system's equivalent:\n"
+        "\n"
+        "  " LIBGCC_DIR "/" LIBGCC_S_SO "\n"
+        "  " STDCXX_DIR "/" LIBSTDCXX_SO "\n", argv[0], argv[0], argv[0]);
+      return 0;
+    } else if (strcmp(argv[i], "-v") == 0 || strcmp(argv[i], "--verbose") == 0) {
+      v = 1;
+    } else if (strcmp(argv[i], "-c") == 0 || strcmp(argv[i], "--copy-libraries") == 0) {
+      copy = 1;
+    } else {
+      fprintf(stderr, "error: invalid argument: %s\nTry `%s --help' for more information.\n", argv[i], argv[0]);
+      return 1;
+    }
+  }
+
+  char *currdir = realpath("/proc/self/exe", NULL);
+  if (!currdir) {
+    fprintf(stderr, "error: realpath() failed to resolve /proc/self/exe\n");
+    return 1;
+  }
+
+  char *p = strrchr(currdir, '/');
+  if (!p) {
+    perror("strrchr()");
+    free(currdir);
+    return 1;
+  }
+  *(p+1) = 0;
+
+  int ver;
+  size_t len = strlen(currdir);
+  char *libpath = malloc(len + MAX(sizeof(STDCXX_DIR), sizeof(LIBGCC_DIR)) +
+    MAX(sizeof(LIBSTDCXX_SO), sizeof(LIBGCC_S_SO)) + 2);
+  strcpy(libpath, currdir);
+  p = libpath + len;
+
+  if (copy) {
+    /* copy system libraries */
+    strcpy(p, LIBGCC_DIR);
+    copy_lib(LIBGCC_S_SO, libpath, v);
+    strcpy(p, STDCXX_DIR);
+    copy_lib(LIBSTDCXX_SO, libpath, v);
+  } else {
+    /* get symbol versions */
+    strcpy(p, LIBGCC_DIR "/" LIBGCC_S_SO);
+    ver = symbol_version(libpath, "GCC_", v);
+    if (ver != -1 && ver > symbol_version(LIBGCC_S_SO, "GCC_", v)) {
+      printf("%s" LIBGCC_DIR ":", currdir);
+    }
+
+    strcpy(p, STDCXX_DIR "/" LIBSTDCXX_SO);
+    ver = symbol_version(libpath, "GLIBCXX_", v);
+    if (ver != -1 && ver > symbol_version(LIBSTDCXX_SO, "GLIBCXX_", v)) {
+      printf("%s" STDCXX_DIR ":", currdir);
+    }
+
+    putchar('\n');
+  }
+
+  free(libpath);
+  free(currdir);
+#endif
+
+  return 0;
+}
+
+
+

src/env.c

@@ -0,0 +1,134 @@
+/* Copyright (c) 2018 Pablo Marcos Oltra <pablo.marcos.oltra@gmail.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#define _GNU_SOURCE
+
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <errno.h>
+
+#include "env.h"
+
+static char** env_allocate(size_t size) {
+    return calloc(size + 1, sizeof(char*));
+}
+
+void env_free(char* const *env) {
+    size_t len = 0;
+    while (env[len] != 0) {
+        free(env[len]);
+        len++;
+    }
+    free((char**)env);
+}
+
+pid_t get_parent_pid() {
+    pid_t ppid = 0;
+    char *s_ppid = getenv("PPID");
+
+    if(s_ppid) {
+        ppid = atoi(s_ppid);
+    }
+
+    if (!ppid) {
+        ppid = getppid();
+    }
+
+    return ppid;
+}
+
+static size_t get_number_of_variables(FILE *file, char **buffer, size_t *len) {
+    size_t number = 0;
+
+    if (getline(buffer, len, file) < 0)
+        return -1;
+
+    char *ptr = *buffer;
+    while (ptr < *buffer + *len) {
+        size_t var_len = strlen(ptr);
+        ptr += var_len + 1;
+        if (var_len == 0)
+            break;
+        number++;
+    }
+
+    return number != 0 ? (ssize_t)number : -1;
+}
+
+static char* const* env_from_buffer(FILE *file) {
+    char *buffer = NULL;
+    size_t len = 0;
+    size_t num_vars = get_number_of_variables(file, &buffer, &len);
+    char** env = env_allocate(num_vars);
+
+    size_t n = 0;
+    char *ptr = buffer;
+    while (ptr < buffer + len && n < num_vars) {
+        size_t var_len = strlen(ptr);
+        if (var_len == 0)
+            break;
+
+        env[n] = calloc(sizeof(char*), var_len + 1);
+        strncpy(env[n], ptr, var_len + 1);
+        DEBUG("\tenv var copied: %s\n", env[n]);
+        ptr += var_len + 1;
+        n++;
+    }
+    free(buffer);
+
+    return env;
+}
+
+static char* const* read_env_from_process(pid_t pid) {
+    char buffer[256] = {0};
+
+    snprintf(buffer, sizeof(buffer), "/proc/%d/environ", pid);
+    DEBUG("Reading env from parent process: %s\n", buffer);
+    FILE *env_file = fopen(buffer, "r");
+    if (!env_file) {
+        DEBUG("Error reading file: %s (%s)\n", buffer, strerror(errno));
+        return NULL;
+    }
+
+    char* const* env = env_from_buffer(env_file);
+    fclose(env_file);
+
+    return env;
+}
+
+char* const* read_parent_env() {
+    pid_t ppid = get_parent_pid();
+    return read_env_from_process(ppid);
+}
+
+#ifdef ENV_TEST
+int main() {
+    putenv("APPIMAGE_CHECKRT_DEBUG=1");
+    DEBUG("ENV TEST\n");
+    char **env = NULL;
+    read_parent_env(&env);
+
+    return 0;
+}
+#endif
+

src/env.h

@@ -0,0 +1,16 @@
+#ifndef ENV_H
+#define END_H
+
+#include <stdio.h>
+#include <unistd.h>
+
+pid_t get_parent_pid();
+char* const* read_parent_env();
+void env_free(char* const *env);
+
+#define DEBUG(...) do { \
+    if (getenv("APPIMAGE_CHECKRT_DEBUG")) \
+        printf("APPIMAGE_CHECKRT>> " __VA_ARGS__); \
+} while (0)
+
+#endif

src/exec.c

@@ -0,0 +1,134 @@
+/* Copyright (c) 2018 Pablo Marcos Oltra <pablo.marcos.oltra@gmail.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+/*
+ * This exec.so library is intended to restore the environment of the AppImage's
+ * parent process. This is done to avoid library clashing of bundled libraries
+ * with external processes. e.g when running the web browser
+ *
+ * The intended usage is as follows:
+ *
+ * 1. This library is injected to the dynamic loader through LD_PRELOAD
+ *    automatically in AppRun **only** if `usr/optional/exec.so` exists:
+ *    e.g `LD_PRELOAD=$APPDIR/usr/optional/exec.so My.AppImage`
+ *
+ * 2. This library will intercept calls to new processes and will detect whether
+ *    those calls are for binaries within the AppImage bundle or external ones.
+ *
+ * 3. In case it's an internal process, it will not change anything.
+ *    In case it's an external process, it will restore the environment of
+ *    the AppImage parent by reading `/proc/[pid]/environ`.
+ *    This is the conservative approach taken.
+ */
+
+#define _GNU_SOURCE
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <dlfcn.h>
+#include <string.h>
+#include <errno.h>
+
+#include "env.h"
+
+typedef int (*execve_func_t)(const char *filename, char *const argv[], char *const envp[]);
+
+#define MIN(X,Y) ((X) < (Y) ? (X) : (Y))
+
+static const char* get_fullpath(const char *filename) {
+    // Try to get the canonical path in case it's a relative path or symbolic
+    // link. Otherwise, use which to get the fullpath of the binary
+    char *fullpath = canonicalize_file_name(filename);
+    DEBUG("filename %s, canonical path %s\n", filename, fullpath);
+    if (fullpath)
+        return fullpath;
+
+    return filename;
+}
+
+static int is_external_process(const char *filename) {
+    const char *appdir = getenv("APPDIR");
+    if (!appdir)
+        return 0;
+    DEBUG("APPDIR = %s\n", appdir);
+
+    return strncmp(filename, appdir, MIN(strlen(filename), strlen(appdir)));
+}
+
+static int exec_common(execve_func_t function, const char *filename, char* const argv[], char* const envp[]) {
+    const char *fullpath = get_fullpath(filename);
+    DEBUG("filename %s, fullpath %s\n", filename, fullpath);
+    char* const *env = envp;
+    if (is_external_process(fullpath)) {
+        DEBUG("External process detected. Restoring env vars from parent %d\n", get_parent_pid());
+        env = read_parent_env();
+        if (!env) {
+            env = envp;
+            DEBUG("Error restoring env vars from parent\n");
+        }
+    }
+    int ret = function(filename, argv, env);
+
+    if (fullpath != filename)
+        free((char*)fullpath);
+    if (env != envp)
+        env_free(env);
+
+    return ret;
+}
+
+int execve(const char *filename, char *const argv[], char *const envp[]) {
+    DEBUG("execve call hijacked: %s\n", filename);
+    execve_func_t execve_orig = dlsym(RTLD_NEXT, "execve");
+    if (!execve_orig)
+        DEBUG("Error getting execve original symbol: %s\n", strerror(errno));
+
+    return exec_common(execve_orig, filename, argv, envp);
+}
+
+int execv(const char *filename, char *const argv[]) {
+    DEBUG("execv call hijacked: %s\n", filename);
+    return execve(filename, argv, environ);
+}
+
+int execvpe(const char *filename, char *const argv[], char *const envp[]) {
+    DEBUG("execvpe call hijacked: %s\n", filename);
+    execve_func_t execve_orig = dlsym(RTLD_NEXT, "execvpe");
+    if (!execve_orig)
+        DEBUG("Error getting execvpe original symbol: %s\n", strerror(errno));
+
+    return exec_common(execve_orig, filename, argv, envp);
+}
+
+int execvp(const char *filename, char *const argv[]) {
+    DEBUG("execvp call hijacked: %s\n", filename);
+    return execvpe(filename, argv, environ);
+}
+
+#ifdef EXEC_TEST
+int main(int argc, char *argv[]) {
+    putenv("APPIMAGE_CHECKRT_DEBUG=1");
+    DEBUG("EXEC TEST\n");
+    execv("./env_test", argv);
+
+    return 0;
+}
+#endif