tools/docs: sphinx-build-wrapper: Fix output for duplicated names

When SPHINXDIRS is used, basename may be identical for different
files. If this happens, the summary and error detection won't be
accurate.

Fix it by using relative names from builddir.

While here, don't duplicate names. Report, instead:

- SUCCESS
    output PDF file was built
- FAILED
    latexmk/xelatex didn't build any PDF output
- FAILED: no .tex files were generated
    Sphinx didn't build any tex file for SPHINXDIRS directories
- FAILED ({python exception})
    When a concurrent.futures is catched. Usually indicates an
    internal error at the build logic.

With that, building multiple dirs with the same name is reported
properly:

    $ make V=1 SPHINXDIRS="admin-guide/media driver-api/media userspace-api/media" pdfdocs

    Summary
    =======
    admin-guide/media/pdf/media.pdf  : SUCCESS
    driver-api/media/pdf/media.pdf   : SUCCESS
    userspace-api/media/pdf/media.pdf: SUCCESS

And if at least one of them fails, return code will be 1.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Message-ID: <d4a4f16f6c0c423ad38531a490888be3bf01e574.1758196090.git.mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Author: mchehab

tools/docs/sphinx-build-wrapper

@@ -329,9 +329,6 @@ class SphinxBuilder:
                     continue
 
                 name = name[:-len(tex_suffix)]
-
-                max_len = max(max_len, len(name))
-
                 has_tex = True
 
                 future = executor.submit(self.build_pdf_file, latex_cmd,
@@ -343,34 +340,35 @@ class SphinxBuilder:
 
                 pdf_name = name + ".pdf"
                 pdf_from = os.path.join(from_dir, pdf_name)
+                pdf_to = os.path.join(pdf_dir, pdf_name)
+                out_name = os.path.relpath(pdf_to, self.builddir)
+                max_len = max(max_len, len(out_name))
 
                 try:
                     success = future.result()
 
                     if success and os.path.exists(pdf_from):
-                        pdf_to = os.path.join(pdf_dir, pdf_name)
-
                         os.rename(pdf_from, pdf_to)
 
                         #
                         # if verbose, get the name of built PDF file
                         #
                         if self.verbose:
-                           builds[name] = os.path.relpath(pdf_to, self.builddir)
+                           builds[out_name] = "SUCCESS"
                     else:
-                        builds[name] = "FAILED"
+                        builds[out_name] = "FAILED"
                         build_failed = True
                 except futures.Error as e:
-                    builds[name] = f"FAILED ({repr(e)})"
+                    builds[out_name] = f"FAILED ({repr(e)})"
                     build_failed = True
 
         #
         # Handle case where no .tex files were found
         #
         if not has_tex:
-            name = "Sphinx LaTeX builder"
-            max_len = max(max_len, len(name))
-            builds[name] = "FAILED (no .tex file was generated)"
+            out_name = "LaTeX files"
+            max_len = max(max_len, len(out_name))
+            builds[out_name] = "FAILED: no .tex files were generated"
             build_failed = True
 
         return builds, build_failed, max_len