From 21ca64d8e065c231b21f6b2a23e4c4c7e681add4 Mon Sep 17 00:00:00 2001
From: Luca BRUNO <luca.bruno@coreos.com>
Date: Tue, 16 Nov 2021 16:36:58 +0000
Subject: [PATCH] sysusers/provides: parse and output static IDs

This adds support for parsing static UIDs and GIDs from sysusers.d
fragments, and automatically forwarding them to the generated
'Provides' entries.
It will allow inspecting users/groups with static IDs directly
from package metadata:
```
$ rpm --query --provides --package gdm-41.0-3.fc36.x86_64.rpm
[...]
group(gdm) = 42
user(gdm) = 42
```
---
 sysusers.prov | 41 +++++++++++++++++++++++++++++++++++++----
 1 file changed, 37 insertions(+), 4 deletions(-)

diff --git a/sysusers.prov b/sysusers.prov
index a6eda5d..f12e929 100755
--- a/sysusers.prov
+++ b/sysusers.prov
@@ -1,5 +1,40 @@
 #!/bin/bash
 
+process_u() {
+    if [ ! -z "${2##*[!0-9]*}" ]; then
+        # Single shared static ID.
+        echo "user($1) = $2"
+        echo "group($1) = $2"
+    elif [[ $2 == *:* ]]; then
+        # UID:<group>.
+        uid=$(echo $2 | cut -d':' -f1 -)
+        group=$(echo $2 | cut -d':' -f2 -)
+        if [ ! -z "${group##*[!0-9]*}" ]; then
+            # UID:GID.
+            echo "user($1) = ${uid}"
+            echo "group($1) = ${group}"
+        else
+            # UID:<groupname>.
+            echo "user($1) = ${uid}"
+            echo "group(${group})"
+        fi
+    else
+        # Dynamic (or something else uninteresting).
+        echo "user($1)"
+        echo "group($1)"
+    fi
+}
+
+process_g() {
+    if [ ! -z "${2##*[!0-9]*}" ]; then
+        # Static GID.
+        echo "group($1) = $2"
+    else
+        # Dynamic (or something else uninteresting).
+        echo "group($1)"
+    fi
+}
+
 parse() {
     while read line; do
         [ "${line:0:1}" = '#' -o "${line:0:1}" = ';' ] && continue
@@ -8,12 +43,10 @@ parse() {
         set -- $line
         case "$1" in
             ('u')
-                echo "user($2)"
-                echo "group($2)"
-                # TODO: user:group support
+                process_u "$2" "$3"
                 ;;
             ('g')
-                echo "group($2)"
+                process_g "$2" "$3"
                 ;;
             ('m')
                 echo "user($2)"