[Buildroot] [PATCH] support/scripts: add size-stats-compare script

[Thomas De Schampheleire <patrickdepinguin@gmail.com>]

From: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>

Leverage the CSV files produces by size-stats (make graph-size) to allow
for a comparison of rootfs size between two different buildroot
compilations.

The script takes the file-size CSV files of two compilations as input, and
produces a textual report of the differences per package.
Using the -d/--detail flag, the report will show the file size changes
instead of package size changes.
The -t/--threshold option allows to ignore file size differences smaller
than the given threshold (in bytes).

Signed-off-by: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>
---
 support/scripts/size-stats-compare | 98 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 98 insertions(+)
 create mode 100755 support/scripts/size-stats-compare

diff --git a/support/scripts/size-stats-compare b/support/scripts/size-stats-compare
new file mode 100755
index 0000000..d7eec09
--- /dev/null
+++ b/support/scripts/size-stats-compare
@@ -0,0 +1,98 @@
+#!/usr/bin/env python
+
+# Copyright (C) 2016 Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+# General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+# Compare the rootfs size per package/file with that from another compilation
+# (possibly from a different release).
+
+# This code relies on the output CSV files of 'make graph-size'. If you
+# are comparing to an older Buildroot release, you can consider backporting
+# that feature. See commits:
+#    99aca138c20e1259ac8c23252c223e150d460482 (instrumentation hook)
+#    598c80be8fc7b5ddfcba6f7715d90757033723ef (size-stats script)
+#    24c75fbb38ffeb5c5a7278cf40f4f7cf867502e0 (make graph-size)
+
+import csv
+import argparse
+
+def read_packages_csv(inputf, detail=None):
+    sizes = {}
+    with open(inputf) as f:
+        reader = csv.reader(f)
+        # skip first line (header)
+        next(reader)
+        for row in csv.reader(f):
+            if detail:
+                sizes[row[0]] = int(row[2])
+            else:
+                sizes[row[1]] = int(row[3])
+    return sizes
+
+def compare_sizes(this, other):
+    delta = {}
+    removed = {}
+    added = {}
+    thiskeys = set(this.keys())
+    otherkeys = set(other.keys())
+
+    # packages in both
+    for pkg in thiskeys.intersection(otherkeys):
+        delta[pkg] = this[pkg] - other[pkg]
+    # packages only in this
+    for pkg in thiskeys.difference(otherkeys):
+        added[pkg] = this[pkg]
+    # packages only in other
+    for pkg in otherkeys.difference(thiskeys):
+        removed[pkg] = -other[pkg]
+
+    return delta, added, removed
+
+def print_results(result, title, threshold):
+    print '%s:' % title
+    for pkg in result.keys():
+        if abs(result[pkg]) < threshold:
+            continue
+        print '%12d %s' % (result[pkg], pkg)
+
+
+# main #########################################################################
+
+parser = argparse.ArgumentParser(description='Compare rootfs size between Buildroot compilations')
+
+parser.add_argument('-f', '--file-size-csv',
+                    help='CSV file with file and package size statistics')
+parser.add_argument('-g', '--other-file-size-csv',
+                    help='CSV file with file and package size statistics to compare with')
+parser.add_argument('-d', '--detail', action='store_true',
+                    help='detail with individual files rather than packages')
+parser.add_argument('-t', '--threshold', type=int,
+                    help='threshold value: ignore size differences smaller than this value (bytes)')
+args = parser.parse_args()
+
+sizes = read_packages_csv(args.file_size_csv, args.detail)
+other_sizes = read_packages_csv(args.other_file_size_csv, args.detail)
+
+delta, added, removed = compare_sizes(sizes, other_sizes)
+
+if args.detail:
+    keyword = 'file'
+else:
+    keyword = 'package'
+
+print_results(delta, 'Size difference per %s (bytes)' % keyword, args.threshold)
+print_results(added, 'Size difference due to added %ss (bytes)' % keyword, args.threshold)
+print_results(removed, 'Size difference due to removed %ss (bytes)' % keyword, args.threshold)
-- 
1.9.5