Always take CWD into account when looking up relative paths

libc-bottom-half/headers/public/wasi/libc-find-relpath.h

@@ -57,6 +57,10 @@ int __wasilibc_find_abspath(const char *abspath,
  * `relative` as a malloc'd buffer that will be `realloc`'d to the appropriate
  * size to contain the relative path.
  *
+ * This used to be a weak function for WASI, but since WASIX has a host-side
+ * CWD that can be set, we always need this. The rest of this comment block is
+ * the documentation for the original weak WASI version of it.
+ * 
  * Note that this is a weak symbol and if it's not defined you can use
  * `__wasilibc_find_relpath`. The weak-nature of this symbols means that if it's
  * not otherwise included in the compilation then `chdir` wasn't used an there's
@@ -70,7 +74,7 @@ int __wasilibc_find_relpath_alloc(
     char **relative,
     size_t *relative_len,
     int can_realloc
-) __attribute__((__weak__));
+);
 
 #ifdef __cplusplus
 }

libc-bottom-half/sources/chdir.c

@@ -197,7 +197,10 @@ int chdir(const char *path)
 {
     // we run the legacy chdir function that emulates real
     // current directory functionality for backwards compatibility reasons
-    chdir_legacy(path);
+    if (chdir_legacy(path) != 0) {
+        // chdir_legacy already sets errno
+        return -1;
+    }
 
     // otherwise we let the operating system know we are changing the current path
     __wasi_errno_t error = __wasi_chdir(path);

libc-bottom-half/sources/posix.c

@@ -17,11 +17,8 @@ static int find_relpath2(
     char **relative,
     size_t *relative_len
 ) {
-    // See comments in `preopens.c` for what this trick is doing.
     const char *abs;
-    if (__wasilibc_find_relpath_alloc)
-        return __wasilibc_find_relpath_alloc(path, &abs, relative, relative_len, 1);
-    return __wasilibc_find_relpath(path, &abs, relative, *relative_len);
+    return __wasilibc_find_relpath_alloc(path, &abs, relative, relative_len, 1);
 }
 
 // Helper to call `__wasilibc_find_relpath` and return an already-managed

libc-bottom-half/sources/preopens.c

@@ -160,12 +160,7 @@ int __wasilibc_find_relpath(const char *path,
                             const char **abs_prefix,
                             char **relative_path,
                             size_t relative_path_len) {
-    // If `chdir` is linked, whose object file defines this symbol, then we
-    // call that. Otherwise if the program can't `chdir` then `path` is
-    // absolute (or relative to the root dir), so we delegate to `find_abspath`
-    if (__wasilibc_find_relpath_alloc)
-        return __wasilibc_find_relpath_alloc(path, abs_prefix, relative_path, &relative_path_len, 0);
-    return __wasilibc_find_abspath(path, abs_prefix, (const char**) relative_path);
+    return __wasilibc_find_relpath_alloc(path, abs_prefix, relative_path, &relative_path_len, 0);
 }
 
 // See the documentation in libc-find-relpath.h.