1 files changed, 144 insertions, 0 deletions
diff --git a/scripts/osmo-depcheck/buildstack.py b/scripts/osmo-depcheck/buildstack.py
new file mode 100644
index 0000000..87210ab
--- /dev/null
+++ b/scripts/osmo-depcheck/buildstack.py
@@ -0,0 +1,144 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+# Copyright 2018 sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+
+import atexit
+import collections
+import sys
+import os
+import shutil
+import subprocess
+import tempfile
+
+
+def next_buildable(depends, done):
+    """ Find the next program that can be built, because it has all
+        dependencies satisfied. Initially this would be libosmocore, as it has
+        no dependencies, then the only library that depends on libosmocore and
+        so on.
+
+        :param depends: return value of dependencies.generate()
+        :param done: ordered dict of programs that would already have been
+                     built at this point.
+                     Example: {"lib-a": "0.11.0", "lib-b": "0.5.0"}
+    """
+    # Iterate over dependencies
+    for program, data in depends.items():
+        # Skip what's already done
+        if program in done:
+            continue
+
+        # Check for missing dependencies
+        depends_done = True
+        for depend in data["depends"]:
+            if depend not in done:
+                depends_done = False
+                break
+
+        # All dependencies satisfied: we have a winner!
+        if depends_done:
+            return program, data["version"]
+
+    # Impossible to build the dependency tree
+    print_dict(done)
+    print("ERROR: can't figure out how to build the rest!")
+    sys.exit(1)
+
+
+def generate(depends):
+    """ Generate an ordered dictionary with the right build order.
+
+        :param depends: return value of dependencies.generate()
+        :returns: an ordered dict like the following:
+                  {"libosmocore": "0.11.0",
+                   "libosmo-abis": "0.5.0",
+                   "osmo-bts": "master"} """
+    # Iterate over dependencies
+    ret = collections.OrderedDict()
+    count = len(depends.keys())
+    while len(ret) != count:
+        # Continue with the one without unsatisfied dependencies
+        program, version = next_buildable(depends, ret)
+        ret[program] = version
+    return ret
+
+
+def print_dict(stack):
+    """ Print the whole build stack.
+        :param stack: return value from generate() above """
+    print("Build order:")
+    for program, version in stack.items():
+        print(" * " + program + ":" + version)
+
+
+def temp_install_folder():
+    """ Generate a temporary installation folder
+
+        It will be used as configure prefix, so when running 'make install',
+        the files will get copied in there instead of "/usr/local/". The folder
+        will get removed when the script has finished.
+
+        :returns: the path to the temporary folder """
+    ret = tempfile.mkdtemp(prefix="depcheck_")
+    atexit.register(shutil.rmtree, ret)
+    print("Temporary install folder: " + ret)
+    return ret
+
+
+def set_environment(jobs, tempdir):
+    """ Configure the environment variables before running configure, make etc.
+
+        :param jobs: parallel build jobs (for make)
+        :param tempdir: temporary installation dir (see temp_install_folder())
+    """
+    # Add tempdir to PKG_CONFIG_PATH and LD_LIBRARY_PATH
+    extend = {"PKG_CONFIG_PATH": tempdir + "/lib/pkgconfig",
+              "LD_LIBRARY_PATH": tempdir + "/lib"}
+    for env_var, folder in extend.items():
+        old = os.environ[env_var] if env_var in os.environ else ""
+        os.environ[env_var] = old + ":" + folder
+
+    # Set JOBS for make
+    os.environ["JOBS"] = str(jobs)
+
+
+def build(gitdir, jobs, stack):
+    """ Build one program with all its dependencies.
+
+        :param gitdir: folder to which the sources will be cloned
+        :param jobs: parallel build jobs (for make)
+        :param stack: the build stack as returned by generate() above
+
+        The dependencies.clone() function has already downloaded missing
+        sources and checked out the right version tags. So in this function we
+        can directly enter the source folder and run the build commands.
+
+        Notes about the usage of 'make clean' and 'make distclean':
+        * Without 'make clean' we might have files in the build directory with
+          a different prefix hardcoded (e.g. from a previous run of
+          osmo-depcheck):
+          <https://lists.gnu.org/archive/html/libtool/2006-12/msg00011.html>
+        * 'make distclean' gets used to remove everything that mentioned the
+          prefix set by osmo-depcheck. That way the user won't have it set
+          anymore in case they decide to compile the code again manually from
+          the source folder. """
+    # Prepare the install folder and environment
+    tempdir = temp_install_folder()
+    unitdir = tempdir + "/lib/systemd/system/"
+    set_environment(jobs, tempdir)
+
+    # Iterate over stack
+    for program, version in stack.items():
+        print("Building " + program + ":" + version)
+        os.chdir(gitdir + "/" + program)
+
+        # Run the build commands
+        commands = [["autoreconf", "-fi"],
+                    ["./configure", "--prefix", tempdir,
+                     "--with-systemdsystemunitdir=" + unitdir],
+                    ["make", "clean"],
+                    ["make"],
+                    ["make", "install"],
+                    ["make", "distclean"]]
+        for command in commands:
+            print("+ " + " ".join(command))
+            subprocess.run(command, check=True)