Implement get_executable_path() for macOS

[rom1v]

Implement the function to get the executable path on macOS, so that enabling -Dportable=true works on all platforms to find scrcpy-server and icon.png in the same directory as the executable.

@Genxster1998 I stole this from your branch. Thank you 😉

Please review/test on macOS.

[Genxster1998]

@rom1v I tested the build from exec_path branch, it works as expected with both wrapper and directly executing scrcpy_bin (with default adb installation) in macOS 14.5 x86_64. i would suggest to make changes for bundled adb path too.

[rom1v]

One more thing, the scrcpy script does not work if called from a symlink.

For example:

$ ln -s scrcpy-linux-x86_64-v3.0/scrcpy aaa
$ ./aaa
./aaa: line 7: ./scrcpy_bin: No such file or directory

On Linux, readlink -f solves the problem:

diff --git app/data/scrcpy_static_wrapper.sh app/data/scrcpy_static_wrapper.sh
index b31b4f1f4..9e765ca87 100755
--- app/data/scrcpy_static_wrapper.sh
+++ app/data/scrcpy_static_wrapper.sh
@@ -1,4 +1,4 @@
 #!/bin/bash
-cd "$(dirname ${BASH_SOURCE[0]})"
+cd "$(dirname $(readlink -f ${BASH_SOURCE[0]}))"
 export ADB="${ADB:-./adb}"
 ./scrcpy_bin "$@"

also in the case where it's a relative symlink pointing to a relative symlink (which does not work without -f).

However, on macOS, I think readlink behaves differently (-f is not available). There is realpath, but it is not installed by default.

[Genxster1998]

https://stackoverflow.com/questions/7665/how-to-resolve-symbolic-links-in-a-shell-script
Will check few fixes from above.
Yeah ,a wrapper posix shell script won't be stable as binary itself, it would have problem resolving links,args,params etc.
Edit: readlink without -f option works in macOS.
For me realpath is installed at /bin/realpath signed by apple on macOS Sonoma. on some prev. versions some claim its not available.

[rom1v]

I added commits so that scrcpy uses the local adb in portable builds, and I removed the wrapper script completely.

Please test/review 😉

[rom1v]

Edit: readlink without -f option works in macOS.

Without -f, it does not if there are two levels of relative symlinks (on Linux at least).

For example:

ln -s scrcpy-linux-x86_64-v3.0/scrcpy aaa
mkdir bbb
cd bbb
ln -s ../aaa ccc
./ccc

[metayan]

Trying to build 39c3921 on macOS 10.15.7 fails with

[63/130] Compiling C object app/scrcpy.p/src_sys_unix_file.c.o
FAILED: app/scrcpy.p/src_sys_unix_file.c.o 
cc -Iapp/scrcpy.p -Iapp -I../app -I../app/src -I/usr/local/include -I/usr/local/include/SDL2\
 -I/usr/local/Cellar/libusb/1.0.27/include/libusb-1.0 -fdiagnostics-color=always\
 -Wall -Winvalid-pch -Wextra -std=c11 -O0 -g -Wmissing-prototypes -D_THREAD_SAFE -MD -MQ\
 app/scrcpy.p/src_sys_unix_file.c.o -MF app/scrcpy.p/src_sys_unix_file.c.o.d\
 -o app/scrcpy.p/src_sys_unix_file.c.o -c ../app/src/sys/unix/file.c
../app/src/sys/unix/file.c:66:9: error: call to undeclared function '_NSGetExecutablePath';\
 ISO C99 and later do not support implicit function declarations\
 [-Wimplicit-function-declaration]
   66 |     if (_NSGetExecutablePath(buf, &bufsize) != 0) {
      |         ^
1 error generated.

[rom1v]

@metayan Does this help:

diff --git app/src/sys/unix/file.c app/src/sys/unix/file.c
index 60c806bb2..6123c788c 100644
--- app/src/sys/unix/file.c
+++ app/src/sys/unix/file.c
@@ -6,6 +6,9 @@
 #include <string.h>
 #include <sys/stat.h>
 #include <unistd.h>
+#ifdef __APPLE__
+# include <mach-o/dyld.h> // for _NSGetExecutablePath()
+#endif
 
 #include "util/log.h"
 

?

[Genxster1998]

@rom1v
Yeah ,that was obvious, It won't resolve all symbolic links. I linked the stackoverflow query discussing the same.

[metayan]

@rom1v
The include solved it. Builds and works fine.

By the way, the release scripts are also excellent, taking care of the dependencies.
Very useful.

Noticed this, though, unrelated to this PR, but appears when building on macOS:

ld: warning: could not create compact unwind for _kbd_window_init:
 stack subq instruction is too different from dwarf stack size

[rom1v]

ld: warning: could not create compact unwind for _kbd_window_init:
 stack subq instruction is too different from dwarf stack size

https://stackoverflow.com/questions/39598302/ld-warning-stack-subl-instruction-is-too-different-from-dwarf-stack-size-on-os

🤷

[rom1v]

Merged into dev.

I will probably publish a release 3.0.1 soon with the current dev branch, which fixes several issues from 3.0.

[Genxster1998]

I added commits so that scrcpy uses the local adb in portable builds, and I removed the wrapper script completely.

You mean it checks for system wide adb env var or not before using local adb?

[rom1v]

By default, it uses the adb the local directory.

This can be changzd by setting the ADB envvar.

For example:

ADB=adb scrcpy

It will use adb (like in non-portable builds), which will be found in PATH.

[Genxster1998]

@metayan I would strongly suggest you to move to later macOS releases preferably latest 2 releases.Catalina ceased to get security updates in oct 2022 vulnerable to easy root exploits like dirtycow patched in dec 2022 or other tcc exploits.