serialize: add common deserialize_read_line() helper and use it everywhere

This introduces a common helper replacing three very similar uses.

Prompted by review of: #27890

3 files changed, 18 insertions, 30 deletions

diff --git a/src/core/job.c b/src/core/job.c
index acf8a78f41..e7d1f65dbc 100644
--- a/src/core/job.c
+++ b/src/core/job.c
@@ -1233,21 +1233,15 @@ int job_deserialize(Job *j, FILE *f) {
         assert(f);
 
         for (;;) {
-                _cleanup_free_ char *line = NULL;
-                char *l, *v;
+                _cleanup_free_ char *l = NULL;
                 size_t k;
+                char *v;
 
-                r = read_line(f, LONG_LINE_MAX, &line);
+                r = deserialize_read_line(f, &l);
                 if (r < 0)
-                        return log_error_errno(r, "Failed to read serialization line: %m");
-                if (r == 0)
-                        return 0;
-
-                l = strstrip(line);
-
-                /* End marker */
-                if (isempty(l))
-                        return 0;
+                        return r;
+                if (r == 0) /* eof or end marker */
+                        break;
 
                 k = strcspn(l, "=");
 
@@ -1326,6 +1320,8 @@ int job_deserialize(Job *j, FILE *f) {
                 } else
                         log_debug("Unknown job serialization key: %s", l);
         }
+
+        return 0;
 }
 
 int job_coldplug(Job *j) {
diff --git a/src/core/manager-serialize.c b/src/core/manager-serialize.c
index f4ad9b0642..71234ae936 100644
--- a/src/core/manager-serialize.c
+++ b/src/core/manager-serialize.c
@@ -338,17 +338,13 @@ int manager_deserialize(Manager *m, FILE *f, FDSet *fds) {
         _cleanup_(manager_reloading_stopp) _unused_ Manager *reloading = manager_reloading_start(m);
 
         for (;;) {
-                _cleanup_free_ char *line = NULL;
-                const char *val, *l;
+                _cleanup_free_ char *l = NULL;
+                const char *val;
 
-                r = read_line(f, LONG_LINE_MAX, &line);
+                r = deserialize_read_line(f, &l);
                 if (r < 0)
-                        return log_error_errno(r, "Failed to read serialization line: %m");
-                if (r == 0)
-                        break;
-
-                l = strstrip(line);
-                if (isempty(l)) /* end marker */
+                        return r;
+                if (r == 0) /* eof or end marker */
                         break;
 
                 if ((val = startswith(l, "current-job-id="))) {
diff --git a/src/core/unit-serialize.c b/src/core/unit-serialize.c
index cb209c5bde..f0030d3211 100644
--- a/src/core/unit-serialize.c
+++ b/src/core/unit-serialize.c
@@ -272,19 +272,15 @@ int unit_deserialize(Unit *u, FILE *f, FDSet *fds) {
         assert(fds);
 
         for (;;) {
-                _cleanup_free_ char *line = NULL;
-                char *l, *v;
+                _cleanup_free_ char *l  = NULL;
                 ssize_t m;
                 size_t k;
+                char *v;
 
-                r = read_line(f, LONG_LINE_MAX, &line);
+                r = deserialize_read_line(f, &l);
                 if (r < 0)
-                        return log_error_errno(r, "Failed to read serialization line: %m");
-                if (r == 0) /* eof */
-                        break;
-
-                l = strstrip(line);
-                if (isempty(l)) /* End marker */
+                        return r;
+                if (r == 0) /* eof or end marker */
                         break;
 
                 k = strcspn(l, "=");