perf: find path efficiently for clangd argus, close #765.

[ayamir]

@sunchangtan @Groveer

[CharlesChiuGit]

I'm not sure if this will work or not, especially we will have exe, dll, cmd as file extensions on Windows.
But I'm currently working on linux, can't test this part.

sunchangtan and Groveer can test the patch first.

[ayamir]

I'm not sure if this will work or not, especially we will have exe, dll, cmd as file extensions on Windows.
But I'm currently working on linux, can't test this part.

sunchangtan and Groveer can test the patch first.

Test passed on my windows PC, but need more tests to confirm.

[Groveer]

I'm not sure if this will work or not, especially we will have exe, dll, cmd as file extensions on Windows.
But I'm currently working on linux, can't test this part.

sunchangtan and Groveer can test the patch first.

Test passed on my windows PC, but need more tests to confirm.

I test passed. it works good.

[Jint-lzxy]

Also works on my Windows 10 VM :) In fact, checking fs.c - $PATH is correctly resolved:

static bool is_executable_in_path(const char *name, char **abspath)
  FUNC_ATTR_NONNULL_ARG(1)
{
  const char *path_env = os_getenv("PATH");
  // ...... //
  size_t buf_len = strlen(name) + strlen(path) + 2;
  char *buf = xmalloc(buf_len);
  // ...... //

  while (true) {
    char *e = xstrchrnul(p, ENV_SEPCHAR);

    // Combine the $PATH segment with `name`.
    xstrlcpy(buf, p, (size_t)(e - p) + 1);
    append_path(buf, name, buf_len);

#ifdef MSWIN
    if (is_executable_ext(buf, abspath)) {
#else
    // ...... //
#endif
      rv = true;
      goto end;
    }
  // ...... //
}

[sunchangtan]

I'm not sure if this will work or not, especially we will have exe, dll, cmd as file extensions on Windows. But I'm currently working on linux, can't test this part.

sunchangtan and Groveer can test the patch first.

I test passed. it works good.