bootctl: add --install-source=auto|image|host

When using --root=/--image= the binaries to install/update will be
picked from the directory/image. Add an option to let the caller
choose.
By default (auto) the image is tried first, and if nothing is found
then the host. The other options allow to strictly try the image
or host and ignore the other.

1 files changed, 38 insertions, 5 deletions

diff --git a/src/boot/bootctl.c b/src/boot/bootctl.c
index 6cb0f42539..c09c305b3f 100644
--- a/src/boot/bootctl.c
+++ b/src/boot/bootctl.c
@@ -80,6 +80,11 @@ static JsonFormatFlags arg_json_format_flags = JSON_FORMAT_OFF;
 static bool arg_arch_all = false;
 static char *arg_root = NULL;
 static char *arg_image = NULL;
+static enum {
+        ARG_INSTALL_SOURCE_IMAGE,
+        ARG_INSTALL_SOURCE_HOST,
+        ARG_INSTALL_SOURCE_AUTO,
+} arg_install_source = ARG_INSTALL_SOURCE_AUTO;
 
 STATIC_DESTRUCTOR_REGISTER(arg_esp_path, freep);
 STATIC_DESTRUCTOR_REGISTER(arg_xbootldr_path, freep);
@@ -843,6 +848,7 @@ static int create_subdirs(const char *root, const char * const *subdirs) {
 }
 
 static int copy_one_file(const char *esp_path, const char *name, bool force) {
+        char *root = IN_SET(arg_install_source, ARG_INSTALL_SOURCE_AUTO, ARG_INSTALL_SOURCE_IMAGE) ? arg_root : NULL;
         _cleanup_free_ char *source_path = NULL, *dest_path = NULL, *p = NULL, *q = NULL;
         const char *e;
         char *dest_name, *s;
@@ -857,13 +863,16 @@ static int copy_one_file(const char *esp_path, const char *name, bool force) {
         if (!p)
                 return log_oom();
 
-        r = chase_symlinks(p, arg_root, CHASE_PREFIX_ROOT, &source_path, NULL);
+        r = chase_symlinks(p, root, CHASE_PREFIX_ROOT, &source_path, NULL);
+        /* If we had a root directory to try, we didn't find it and we are in auto mode, retry on the host */
+        if (r == -ENOENT && root && arg_install_source == ARG_INSTALL_SOURCE_AUTO)
+                r = chase_symlinks(p, NULL, CHASE_PREFIX_ROOT, &source_path, NULL);
         if (r < 0)
                 return log_error_errno(r,
                                        "Failed to resolve path %s%s%s: %m",
                                        p,
-                                       arg_root ? " under directory " : "",
-                                       arg_root ? arg_root : "");
+                                       root ? " under directory " : "",
+                                       root ?: "");
 
         q = path_join("/EFI/systemd/", dest_name);
         if (!q)
@@ -899,13 +908,17 @@ static int copy_one_file(const char *esp_path, const char *name, bool force) {
 }
 
 static int install_binaries(const char *esp_path, const char *arch, bool force) {
+        char *root = IN_SET(arg_install_source, ARG_INSTALL_SOURCE_AUTO, ARG_INSTALL_SOURCE_IMAGE) ? arg_root : NULL;
         _cleanup_closedir_ DIR *d = NULL;
         _cleanup_free_ char *path = NULL;
         int r;
 
-        r = chase_symlinks_and_opendir(BOOTLIBDIR, arg_root, CHASE_PREFIX_ROOT, &path, &d);
+        r = chase_symlinks_and_opendir(BOOTLIBDIR, root, CHASE_PREFIX_ROOT, &path, &d);
+        /* If we had a root directory to try, we didn't find it and we are in auto mode, retry on the host */
+        if (r == -ENOENT && root && arg_install_source == ARG_INSTALL_SOURCE_AUTO)
+                r = chase_symlinks_and_opendir(BOOTLIBDIR, NULL, CHASE_PREFIX_ROOT, &path, &d);
         if (r < 0)
-                return log_error_errno(r, "Failed to open boot loader directory %s: %m", BOOTLIBDIR);
+                return log_error_errno(r, "Failed to open boot loader directory %s%s: %m", root ?: "", BOOTLIBDIR);
 
         const char *suffix = strjoina(arch, ".efi");
         const char *suffix_signed = strjoina(arch, ".efi.signed");
@@ -1394,6 +1407,8 @@ static int help(int argc, char *argv[], void *userdata) {
                "     --boot-path=PATH  Path to the $BOOT partition\n"
                "     --root=PATH       Operate on an alternate filesystem root\n"
                "     --image=PATH      Operate on disk image as filesystem root\n"
+               "     --install-source=auto|image|host\n"
+               "                       Where to pick files when using --root=/--image=\n"
                "  -p --print-esp-path  Print path to the EFI System Partition\n"
                "  -x --print-boot-path Print path to the $BOOT partition\n"
                "     --no-variables    Don't touch EFI variables\n"
@@ -1426,6 +1441,7 @@ static int parse_argv(int argc, char *argv[]) {
                 ARG_BOOT_PATH,
                 ARG_ROOT,
                 ARG_IMAGE,
+                ARG_INSTALL_SOURCE,
                 ARG_VERSION,
                 ARG_NO_VARIABLES,
                 ARG_NO_PAGER,
@@ -1444,6 +1460,7 @@ static int parse_argv(int argc, char *argv[]) {
                 { "boot-path",                 required_argument, NULL, ARG_BOOT_PATH                 },
                 { "root",                      required_argument, NULL, ARG_ROOT                      },
                 { "image",                     required_argument, NULL, ARG_IMAGE                     },
+                { "install-source",            required_argument, NULL, ARG_INSTALL_SOURCE            },
                 { "print-esp-path",            no_argument,       NULL, 'p'                           },
                 { "print-path",                no_argument,       NULL, 'p'                           }, /* Compatibility alias */
                 { "print-boot-path",           no_argument,       NULL, 'x'                           },
@@ -1499,6 +1516,19 @@ static int parse_argv(int argc, char *argv[]) {
                                 return r;
                         break;
 
+                case ARG_INSTALL_SOURCE:
+                        if (streq(optarg, "auto"))
+                                arg_install_source = ARG_INSTALL_SOURCE_AUTO;
+                        else if (streq(optarg, "image"))
+                                arg_install_source = ARG_INSTALL_SOURCE_IMAGE;
+                        else if (streq(optarg, "host"))
+                                arg_install_source = ARG_INSTALL_SOURCE_HOST;
+                        else
+                                return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+                                                       "Unexpected parameter for --install-source=: %s", optarg);
+
+                        break;
+
                 case 'p':
                         if (arg_print_dollar_boot_path)
                                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
@@ -1592,6 +1622,9 @@ static int parse_argv(int argc, char *argv[]) {
         if (arg_root && arg_image)
                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Please specify either --root= or --image=, the combination of both is not supported.");
 
+        if (arg_install_source != ARG_INSTALL_SOURCE_AUTO && !arg_root && !arg_image)
+                return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "--install-from-host is only supported with --root= or --image=.");
+
         return 1;
 }