Brad Bishop | 1a4b7ee | 2018-12-16 17:11:34 -0800 | [diff] [blame^] | 1 | #!/usr/bin/env python3 |
| 2 | |
| 3 | import os |
| 4 | import sys |
| 5 | |
| 6 | def bail(msg): |
| 7 | print(msg, file=sys.stderr) |
| 8 | sys.exit(1) |
| 9 | |
| 10 | _MARKER = '@@' |
| 11 | def transform_line(line): |
| 12 | # Substitute any special markers of this form: |
| 13 | # @@ENV@@ |
| 14 | # with the value of ENV, split into meson array syntax. |
| 15 | start = line.find(_MARKER) |
| 16 | if start == -1: |
| 17 | return line |
| 18 | |
| 19 | end = line.rfind(_MARKER) |
| 20 | if end == start: |
| 21 | return line |
| 22 | |
| 23 | # Lookup value of the env var. |
| 24 | var = line[start+len(_MARKER):end] |
| 25 | try: |
| 26 | val = os.environ[var] |
| 27 | except KeyError: |
| 28 | bail('cannot generate meson.cross; env var %s not set' % var) |
| 29 | |
| 30 | # Transform into meson array. |
| 31 | val = ["'%s'" % x for x in val.split()] |
| 32 | val = ', '.join(val) |
| 33 | val = '[%s]' % val |
| 34 | |
| 35 | before = line[:start] |
| 36 | after = line[end+len(_MARKER):] |
| 37 | |
| 38 | return '%s%s%s' % (before, val, after) |
| 39 | |
| 40 | # Make sure this is really an SDK extraction environment. |
| 41 | try: |
| 42 | sysroot = os.environ['OECORE_NATIVE_SYSROOT'] |
| 43 | except KeyError: |
| 44 | bail('OECORE_NATIVE_SYSROOT env var must be set') |
| 45 | |
| 46 | cross_file = os.path.join(sysroot, 'usr/share/meson/meson.cross') |
| 47 | tmp_cross_file = '%s.tmp' % cross_file |
| 48 | |
| 49 | # Read through and transform the current meson.cross. |
| 50 | lines = [] |
| 51 | with open(cross_file, 'r') as f: |
| 52 | for line in f: |
| 53 | lines.append(transform_line(line)) |
| 54 | |
| 55 | # Write the transformed result to a tmp file and atomically rename it. In case |
| 56 | # we crash during the file write, we don't want an invalid meson.cross file. |
| 57 | with open(tmp_cross_file, 'w') as f: |
| 58 | for line in lines: |
| 59 | f.write(line) |
| 60 | f.flush() |
| 61 | os.fdatasync(f.fileno()) |
| 62 | os.rename(tmp_cross_file, cross_file) |