[OE-core] [PATCH] classes/sstate: Update output hash

[Joshua Watt]

Updates the output hash calculation for determining if tasks are
equivalent. The new algorithm does the following based on feedback:
 1) All files are printed in a single line tabular format
 2) Prints the file type and mode in a user-friendly ls-like format
 3) Includes the file owner and group (by name, not ID). These are only
    included if the task is run under pseudo, since that is the only
    time they can be consistently determined.
 4) File size is included for regular files

Signed-off-by: Joshua Watt <JPEWhacker at gmail.com>
---
 meta/classes/sstate.bbclass | 91 +++++++++++++++++++++++++++++++------
 1 file changed, 76 insertions(+), 15 deletions(-)

diff --git a/meta/classes/sstate.bbclass b/meta/classes/sstate.bbclass
index 482ffa83f98..a103a759825 100644
--- a/meta/classes/sstate.bbclass
+++ b/meta/classes/sstate.bbclass
@@ -784,6 +784,8 @@ python sstate_sign_package () {
 def OEOuthashBasic(path, sigfile, task, d):
     import hashlib
     import stat
+    import pwd
+    import grp
 
     def update_hash(s):
         s = s.encode('utf-8')
@@ -793,6 +795,7 @@ def OEOuthashBasic(path, sigfile, task, d):
 
     h = hashlib.sha256()
     prev_dir = os.getcwd()
+    include_owners = os.environ.get('PSEUDO_DISABLED') == '0'
 
     try:
         os.chdir(path)
@@ -807,34 +810,92 @@ def OEOuthashBasic(path, sigfile, task, d):
         update_hash("task=%s\n" % task)
 
         for root, dirs, files in os.walk('.', topdown=True):
-            # Sort directories and files to ensure consistent ordering
+            # Sort directories to ensure consistent ordering when recursing
             dirs.sort()
             files.sort()
 
-            for f in files:
-                path = os.path.join(root, f)
+            def process(path):
                 s = os.lstat(path)
 
-                # Hash file path
-                update_hash(path + '\n')
+                if stat.S_ISDIR(s.st_mode):
+                    update_hash('d')
+                elif stat.S_ISCHR(s.st_mode):
+                    update_hash('c')
+                elif stat.S_ISBLK(s.st_mode):
+                    update_hash('b')
+                elif stat.S_ISSOCK(s.st_mode):
+                    update_hash('s')
+                elif stat.S_ISLNK(s.st_mode):
+                    update_hash('l')
+                elif stat.S_ISFIFO(s.st_mode):
+                    update_hash('p')
+                else:
+                    update_hash('-')
+
+                def add_perm(mask, on, off='-'):
+                    if mask & s.st_mode:
+                        update_hash(on)
+                    else:
+                        update_hash(off)
+
+                add_perm(stat.S_IRUSR, 'r')
+                add_perm(stat.S_IWUSR, 'w')
+                if stat.S_ISUID & s.st_mode:
+                    add_perm(stat.S_IXUSR, 's', 'S')
+                else:
+                    add_perm(stat.S_IXUSR, 'x')
 
-                # Hash file mode
-                update_hash("\tmode=0x%x\n" % stat.S_IMODE(s.st_mode))
-                update_hash("\ttype=0x%x\n" % stat.S_IFMT(s.st_mode))
+                add_perm(stat.S_IRGRP, 'r')
+                add_perm(stat.S_IWGRP, 'w')
+                if stat.S_ISGID & s.st_mode:
+                    add_perm(stat.S_IXGRP, 's', 'S')
+                else:
+                    add_perm(stat.S_IXGRP, 'x')
 
-                if stat.S_ISBLK(s.st_mode) or stat.S_ISBLK(s.st_mode):
-                    # Hash device major and minor
-                    update_hash("\tdev=%d,%d\n" % (os.major(s.st_rdev), os.minor(s.st_rdev)))
-                elif stat.S_ISLNK(s.st_mode):
-                    # Hash symbolic link
-                    update_hash("\tsymlink=%s\n" % os.readlink(path))
+                add_perm(stat.S_IROTH, 'r')
+                add_perm(stat.S_IWOTH, 'w')
+                if stat.S_ISVTX & s.st_mode:
+                    update_hash('t')
+                else:
+                    add_perm(stat.S_IXOTH, 'x')
+
+                if include_owners:
+                    #update_hash(" %5d" % s.st_uid)
+                    #update_hash(" %5d" % s.st_gid)
+                    update_hash(" %10s" % pwd.getpwuid(s.st_uid).pw_name)
+                    update_hash(" %10s" % grp.getgrgid(s.st_gid).gr_name)
+
+                if stat.S_ISBLK(s.st_mode) or stat.S_ISCHR(s.st_mode):
+                    update_hash(" %9s" % ("%d.%d" % (os.major(s.st_rdev), os.minor(s.st_rdev))))
                 else:
+                    update_hash(" " * 10)
+
+                if stat.S_ISREG(s.st_mode):
+                    update_hash(" %10d" % s.st_size)
+                else:
+                    update_hash(" " * 11)
+
+                update_hash(" %s" % path)
+
+                if stat.S_ISLNK(s.st_mode):
+                    update_hash(" -> %s" % os.readlink(path))
+
+                if stat.S_ISREG(s.st_mode):
                     fh = hashlib.sha256()
                     # Hash file contents
                     with open(path, 'rb') as d:
                         for chunk in iter(lambda: d.read(4096), b""):
                             fh.update(chunk)
-                    update_hash("\tdigest=%s\n" % fh.hexdigest())
+                    update_hash(" %s" % fh.hexdigest())
+
+                update_hash("\n")
+
+            # Process this directory and all its child files
+            process(root)
+            for f in files:
+                if f == 'fixmepath':
+                    continue
+                process(os.path.join(root, f))
     finally:
         os.chdir(prev_dir)
 
-- 
2.20.1