From f5d178f87928884c7abdc3fe653604b80419997b Mon Sep 17 00:00:00 2001
From: anon <anon@anon.anon>
Date: Fri, 24 Jan 2025 12:41:02 +0100
Subject: [PATCH] implement chown

---
 source/directive.c  | 17 +++++++++++------
 source/error.c      |  3 +++
 source/error.h      |  3 +++
 source/file_utils.c | 15 ++++++++-------
 4 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/source/directive.c b/source/directive.c
index 821c2a7..af91b20 100644
--- a/source/directive.c
+++ b/source/directive.c
@@ -122,12 +122,12 @@ int make_directive_file(FILE * f) {
         }
         // Owner
         if (do_owner) {
-            struct passwd * pw = getpwuid(entry->st.st_uid);
-            struct group  * gr = getgrgid(entry->st.st_gid);
+            struct passwd * usr = getpwuid(entry->st.st_uid);
+            struct group  * grp = getgrgid(entry->st.st_gid);
 
             fprintf(f, "\t%s:%s",
-                pw->pw_name,
-                gr->gr_name
+                usr->pw_name,
+                grp->gr_name
             );
         }
         // Name
@@ -199,8 +199,13 @@ int execute_directive_file(FILE * f) {
         // Owner
         if (do_owner) {
             char buffer2[113];
-            sscanf(sp, "%s:%s\t", buffer, buffer2);
-            //mychown(filename, buffer, buffer2);
+            sscanf(sp, "%[^:]:%s\t", buffer, buffer2);
+            struct passwd * usr = getpwuid(entry->st.st_uid);
+            struct group  * grp = getgrgid(entry->st.st_gid);
+            if (strcmp(usr->pw_name, buffer)
+            ||  strcmp(grp->gr_name, buffer2)) {
+                mychown(entry->name, buffer, buffer2);
+            }
             NEXT_FIELD;
         }
 
diff --git a/source/error.c b/source/error.c
index 106a874..e690c7b 100644
--- a/source/error.c
+++ b/source/error.c
@@ -31,6 +31,9 @@ void errorn(int n, ...) {
         case E_FILE_ACCESS: verror("failed to interact with file '%s'", argv); break;
         case E_FILE_DELETE: verror("failed to delete file '%s'", argv);        break;
         case E_FILE_MOVE:   verror("failed to move '%s' to '%s'", argv);       break;
+        case E_FILE_CHOWN:  verror("failed to chown '%s'", argv);              break;
+        case E_NO_USER:     verror("failed to find the user '%s'", argv);      break;
+        case E_NO_GROUP:    verror("failed to find the group '%s'", argv);     break;
         case E_FORMAT:      verror("directive-file format violation", argv);   break;
         case E_FLAG:        verror("unknown flag '%c'", argv);                 break;
         default: verror("unknown error encountered; this is an illegal inner state", 0); break;
diff --git a/source/error.h b/source/error.h
index 18e506f..a90d45c 100644
--- a/source/error.h
+++ b/source/error.h
@@ -6,6 +6,9 @@ enum {
     E_FILE_ACCESS,
     E_FILE_DELETE,
     E_FILE_MOVE,
+    E_FILE_CHOWN,
+    E_NO_USER,
+    E_NO_GROUP,
     E_FORMAT,
     E_FLAG,
 };
diff --git a/source/file_utils.c b/source/file_utils.c
index fce464a..7492ad0 100644
--- a/source/file_utils.c
+++ b/source/file_utils.c
@@ -194,24 +194,25 @@ int moist_chown(const char * filename, const char * owner, const char * group) {
     uid_t uid = -1;
     gid_t gid = -1;
 
-    struct passwd * pwd = getpwnam(owner);
-    if (!pwd) {
-        fprintf(stderr, "Error: User '%s' not found\n", owner);
+    struct passwd * usr = getpwnam(owner);
+    if (!usr) {
+        errorn(E_NO_USER, owner);
         return 1;
     }
-    uid = pwd->pw_uid;
+    uid = usr->pw_uid;
 
     struct group * grp = getgrnam(group);
     if (!grp) {
-        fprintf(stderr, "Error: Group '%s' not found\n", group);
+        errorn(E_NO_GROUP, group);
         return 1;
     }
     gid = grp->gr_gid;
 
-    if (chown(filename, uid, gid) != 0) {
-        perror("Error changing file ownership");
+    if (chown(filename, uid, gid)) {
+        errorn(E_FILE_CHOWN, filename);
         return 1;
     }
+
     return 0;
 }