machine-id-setup: casting const away is ugly, let's not do it if there's no reason to

[elogind.git] / src / core / machine-id-setup.c

diff --git a/src/core/machine-id-setup.c b/src/core/machine-id-setup.c
index 10965df6236d63715492b98b73f1df704c972997..d8600bde2ddd9b1ab361923507ceaebd2a12a8f4 100644 (file)
--- a/src/core/machine-id-setup.c
+++ b/src/core/machine-id-setup.c
@@ -157,6 +157,37 @@ static int generate(char id[34], const char *root) {
         return 0;
 }
 
+static int get_valid_machine_id(int fd, char id[34]) {
+        char id_to_validate[34];
+
+        assert(fd >= 0);
+        assert(id);
+
+        if (loop_read(fd, id_to_validate, 33, false) == 33 && id_to_validate[32] == '\n') {
+                id_to_validate[32] = 0;
+
+                if (id128_is_valid(id_to_validate)) {
+                        memcpy(id, id_to_validate, 32);
+                        id[32] = '\n';
+                        id[33] = 0;
+                        return 0;
+                }
+        }
+
+        return -EINVAL;
+}
+
+static int write_machine_id(int fd, char id[34]) {
+        assert(fd >= 0);
+        assert(id);
+        lseek(fd, 0, SEEK_SET);
+
+        if (loop_write(fd, id, 33, false) == 33)
+                return 0;
+
+        return -errno;
+}
+
 int machine_id_setup(const char *root) {
         const char *etc_machine_id, *run_machine_id;
         _cleanup_close_ int fd = -1;
@@ -169,11 +200,13 @@ int machine_id_setup(const char *root) {
                 etc_machine_id = "/etc/machine-id";
                 run_machine_id = "/run/machine-id";
         } else {
-                etc_machine_id = strappenda(root, "/etc/machine-id");
-                path_kill_slashes((char*) etc_machine_id);
+                char *x;
 
-                run_machine_id = strappenda(root, "/run/machine-id");
-                path_kill_slashes((char*) run_machine_id);
+                x = strappenda(root, "/etc/machine-id");
+                etc_machine_id = path_kill_slashes(x);
+
+                x = strappenda(root, "/run/machine-id");
+                run_machine_id = path_kill_slashes(x);
         }
 
         RUN_WITH_UMASK(0000) {
@@ -196,7 +229,7 @@ int machine_id_setup(const char *root) {
                                                   "2) /etc/machine-id exists and is empty.\n"
                                                   "3) /etc/machine-id is missing and /etc is writable.\n");
                                 else
-                                        log_error("Cannot open %s: %m", etc_machine_id);
+                                        log_error_errno(errno, "Cannot open %s: %m", etc_machine_id);
                                 return -errno;
                         }
 
@@ -204,18 +237,11 @@ int machine_id_setup(const char *root) {
                 }
         }
 
-        if (fstat(fd, &st) < 0) {
-                log_error("fstat() failed: %m");
-                return -errno;
-        }
+        if (fstat(fd, &st) < 0)
+                return log_error_errno(errno, "fstat() failed: %m");
 
-        if (S_ISREG(st.st_mode))
-                if (loop_read(fd, id, 33, false) == 33 && id[32] == '\n') {
-                        id[32] = 0;
-
-                        if (id128_is_valid(id))
-                                return 0;
-                }
+        if (S_ISREG(st.st_mode) && get_valid_machine_id(fd, id) == 0)
+                return 0;
 
         /* Hmm, so, the id currently stored is not useful, then let's
          * generate one */
@@ -225,9 +251,7 @@ int machine_id_setup(const char *root) {
                 return r;
 
         if (S_ISREG(st.st_mode) && writable) {
-                lseek(fd, 0, SEEK_SET);
-
-                if (loop_write(fd, id, 33, false) == 33)
+                if (write_machine_id(fd, id) == 0)
                         return 0;
         }
 
@@ -248,7 +272,7 @@ int machine_id_setup(const char *root) {
         /* And now, let's mount it over */
         r = mount(run_machine_id, etc_machine_id, NULL, MS_BIND, NULL);
         if (r < 0) {
-                log_error("Failed to mount %s: %m", etc_machine_id);
+                log_error_errno(errno, "Failed to mount %s: %m", etc_machine_id);
                 unlink_noerrno(run_machine_id);
                 return -errno;
         }
@@ -257,7 +281,7 @@ int machine_id_setup(const char *root) {
 
         /* Mark the mount read-only */
         if (mount(NULL, etc_machine_id, NULL, MS_BIND|MS_RDONLY|MS_REMOUNT, NULL) < 0)
-                log_warning("Failed to make transient %s read-only: %m", etc_machine_id);
+                log_warning_errno(errno, "Failed to make transient %s read-only: %m", etc_machine_id);
 
         return 0;
 }