SL-15742: Convert build scripts to Python 3

This changeset makes it possible to build the Second Life viewer using
Python 3. It is designed to be used with an equivalent Autobuild branch
so that a developer can compile without needing Python 2 on their
machine.

Breaking change: Python 2 support ending

Rather than supporting two versions of Python, including one that was
discontinued at the beginning of the year, this branch focuses on
pouring future effort into Python 3 only. As a result, scripts do not
need to be backwards compatible. This means that build environments,
be they on personal computers and on build agents, need to have a
compatible interpreter.

Notes

- SLVersionChecker will still use Python 2 on macOS
- Fixed the message template url used by template_verifier.py

3 files changed, 23 insertions, 45 deletions

diff --git a/indra/cmake/Python.cmake b/indra/cmake/Python.cmake
index a81c9307fc..ed595f6966 100644
--- a/indra/cmake/Python.cmake
+++ b/indra/cmake/Python.cmake
@@ -6,47 +6,27 @@ if (WINDOWS)
   # On Windows, explicitly avoid Cygwin Python.
 
   find_program(PYTHON_EXECUTABLE
-    NAMES python25.exe python23.exe python.exe
+    NAMES python.exe
     NO_DEFAULT_PATH # added so that cmake does not find cygwin python
     PATHS
-    [HKEY_LOCAL_MACHINE\\SOFTWARE\\Python\\PythonCore\\2.7\\InstallPath]
-    [HKEY_LOCAL_MACHINE\\SOFTWARE\\Python\\PythonCore\\2.6\\InstallPath]
-    [HKEY_LOCAL_MACHINE\\SOFTWARE\\Python\\PythonCore\\2.5\\InstallPath]
-    [HKEY_LOCAL_MACHINE\\SOFTWARE\\Python\\PythonCore\\2.4\\InstallPath]
-    [HKEY_LOCAL_MACHINE\\SOFTWARE\\Python\\PythonCore\\2.3\\InstallPath]
-    [HKEY_CURRENT_USER\\SOFTWARE\\Python\\PythonCore\\2.7\\InstallPath]
-    [HKEY_CURRENT_USER\\SOFTWARE\\Python\\PythonCore\\2.6\\InstallPath]
-    [HKEY_CURRENT_USER\\SOFTWARE\\Python\\PythonCore\\2.5\\InstallPath]
-    [HKEY_CURRENT_USER\\SOFTWARE\\Python\\PythonCore\\2.4\\InstallPath]
-    [HKEY_CURRENT_USER\\SOFTWARE\\Python\\PythonCore\\2.3\\InstallPath]
-    )
-elseif (EXISTS /etc/debian_version)
-  # On Debian and Ubuntu, avoid Python 2.4 if possible.
-
-  find_program(PYTHON_EXECUTABLE python PATHS /usr/bin)
-
-  if (PYTHON_EXECUTABLE)
-    set(PYTHONINTERP_FOUND ON)
-  endif (PYTHON_EXECUTABLE)
-elseif (${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
-  # On MAC OS X be sure to search standard locations first
-
-  string(REPLACE ":" ";" PATH_LIST "$ENV{PATH}")
-  find_program(PYTHON_EXECUTABLE
-    NAMES python python25 python24 python23
-    NO_DEFAULT_PATH # Avoid searching non-standard locations first
-    PATHS
-    /bin
-    /usr/bin
-    /usr/local/bin
-    ${PATH_LIST}
+    [HKEY_LOCAL_MACHINE\\SOFTWARE\\Python\\PythonCore\\3.7\\InstallPath]
+    [HKEY_LOCAL_MACHINE\\SOFTWARE\\Python\\PythonCore\\3.8\\InstallPath]
+    [HKEY_LOCAL_MACHINE\\SOFTWARE\\Python\\PythonCore\\3.9\\InstallPath]
+    [HKEY_LOCAL_MACHINE\\SOFTWARE\\Python\\PythonCore\\3.10\\InstallPath]
+    [HKEY_LOCAL_MACHINE\\SOFTWARE\\Python\\PythonCore\\3.11\\InstallPath]
+    [HKEY_CURRENT_USER\\SOFTWARE\\Python\\PythonCore\\3.7\\InstallPath]
+    [HKEY_CURRENT_USER\\SOFTWARE\\Python\\PythonCore\\3.8\\InstallPath]
+    [HKEY_CURRENT_USER\\SOFTWARE\\Python\\PythonCore\\3.9\\InstallPath]
+    [HKEY_CURRENT_USER\\SOFTWARE\\Python\\PythonCore\\3.10\\InstallPath]
+    [HKEY_LOCAL_MACHINE\\SOFTWARE\\Python\\PythonCore\\3.11\\InstallPath]
     )
+    include(FindPythonInterp)
+else()
+  find_program(PYTHON_EXECUTABLE python3)
 
   if (PYTHON_EXECUTABLE)
     set(PYTHONINTERP_FOUND ON)
   endif (PYTHON_EXECUTABLE)
-else (WINDOWS)
-  include(FindPythonInterp)
 endif (WINDOWS)
 
 if (NOT PYTHON_EXECUTABLE)
diff --git a/indra/cmake/Variables.cmake b/indra/cmake/Variables.cmake
index c81b22e572..e72475cbc4 100644
--- a/indra/cmake/Variables.cmake
+++ b/indra/cmake/Variables.cmake
@@ -60,7 +60,7 @@ if (EXISTS ${CMAKE_SOURCE_DIR}/Server.cmake)
   set(INSTALL_PROPRIETARY ON CACHE BOOL "Install proprietary binaries")
 endif (EXISTS ${CMAKE_SOURCE_DIR}/Server.cmake)
 set(TEMPLATE_VERIFIER_OPTIONS "" CACHE STRING "Options for scripts/template_verifier.py")
-set(TEMPLATE_VERIFIER_MASTER_URL "http://bitbucket.org/lindenlab/master-message-template/raw/tip/message_template.msg" CACHE STRING "Location of the master message template")
+set(TEMPLATE_VERIFIER_MASTER_URL "https://bitbucket.org/lindenlab/master-message-template-git/raw/master/message_template.msg" CACHE STRING "Location of the master message template")
 
 if (NOT CMAKE_BUILD_TYPE)
   set(CMAKE_BUILD_TYPE RelWithDebInfo CACHE STRING
diff --git a/indra/cmake/run_build_test.py b/indra/cmake/run_build_test.py
index ec5d33f902..1e92868ae7 100755
--- a/indra/cmake/run_build_test.py
+++ b/indra/cmake/run_build_test.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 """\
 @file   run_build_test.py
 @author Nat Goodspeed
@@ -17,7 +17,7 @@ line.
 
 Example:
 
-python run_build_test.py -DFOO=bar myprog somearg otherarg
+python3 run_build_test.py -DFOO=bar myprog somearg otherarg
 
 sets environment variable FOO=bar, then runs:
 myprog somearg otherarg
@@ -47,7 +47,7 @@ $/LicenseInfo$
 import os
 import sys
 import errno
-import HTMLParser
+import html.parser
 import re
 import signal
 import subprocess
@@ -111,10 +111,10 @@ def main(command, arguments=[], libpath=[], vars={}):
     # Now handle arbitrary environment variables. The tricky part is ensuring
     # that all the keys and values we try to pass are actually strings.
     if vars:
-        for key, value in vars.items():
+        for key, value in list(vars.items()):
             # As noted a few lines above, facilitate copy-paste rerunning.
             log.info("%s='%s' \\" % (key, value))
-    os.environ.update(dict([(str(key), str(value)) for key, value in vars.iteritems()]))
+    os.environ.update(dict([(str(key), str(value)) for key, value in vars.items()]))
     # Run the child process.
     command_list = [command]
     command_list.extend(arguments)
@@ -177,7 +177,7 @@ def translate_rc(rc):
         try:
             table = get_windows_table()
             symbol, desc = table[hexrc]
-        except Exception, err:
+        except Exception as err:
             log.error("(%s -- carrying on)" % err)
             log.error("terminated with rc %s (%s)" % (rc, hexrc))
         else:
@@ -194,7 +194,7 @@ def translate_rc(rc):
             strc = str(rc)
         return "terminated by signal %s" % strc
 
-class TableParser(HTMLParser.HTMLParser):
+class TableParser(html.parser.HTMLParser):
     """
     This HTMLParser subclass is designed to parse the table we know exists
     in windows-rcs.html, hopefully without building in too much knowledge of
@@ -204,9 +204,7 @@ class TableParser(HTMLParser.HTMLParser):
     whitespace = re.compile(r'\s*$')
 
     def __init__(self):
-        # Because Python 2.x's HTMLParser is an old-style class, we must use
-        # old-style syntax to forward the __init__() call -- not super().
-        HTMLParser.HTMLParser.__init__(self)
+        super().__init__()
         # this will collect all the data, eventually
         self.table = []
         # Stack whose top (last item) indicates where to append current