New API call iso_local_create_dev()

libisofs/aaip-os-dummy.c

@@ -11,7 +11,7 @@
 
  To be included by aaip_0_2.c
 
- Copyright (c) 2009 - 2024 Thomas Schmitt
+ Copyright (c) 2009 - 2025 Thomas Schmitt
 
  This file is part of the libisofs project; you can redistribute it and/or
  modify it under the terms of the GNU General Public License version 2
@@ -176,3 +176,26 @@ int aaip_set_projid(char *path, uint32_t projid, int *os_errno, int flag)
 }
 
 
+
+/* -------- API for creating device files in the local filesystem --------- */
+
+
+/* API */
+/* @param flag  bit0= do not issue error messages
+*/
+int iso_local_create_dev(char *disk_path, mode_t st_mode, dev_t dev,
+                         int *os_errno, int flag)
+{
+ /* From man mknod:
+    POSIX.1-2001 says: "The only portable use of mknod()  is  to  create  a
+    FIFO-special  file.  If mode is not S_IFIFO or dev is not 0, the behav‐
+    ior of mknod() is unspecified."
+ */
+ *os_errno= 0;
+ if(!(flag & 1))
+   iso_msg_submit(-1, ISO_DEV_NO_CREATION, 0,
+   "File \"%s\" cannot be created because device file creation is not enabled",
+                  disk_path);
+ return ISO_DEV_NO_CREATION;
+}
+

libisofs/aaip-os-freebsd.c

@@ -7,7 +7,7 @@
 
  To be included by aaip_0_2.c for FreeBSD, NetBSD, and OpenBSD
 
- Copyright (c) 2009 - 2024 Thomas Schmitt
+ Copyright (c) 2009 - 2025 Thomas Schmitt
 
  This file is part of the libisofs project; you can redistribute it and/or
  modify it under the terms of the GNU General Public License version 2
@@ -1146,3 +1146,44 @@ int aaip_set_projid(char *path, uint32_t projid, int *os_errno, int flag)
 }
 
 
+/* -------- API for creating device files in the local filesystem --------- */
+
+
+/* API */
+/* @param flag  bit0= do not issue error messages
+*/
+int iso_local_create_dev(char *disk_path, mode_t st_mode, dev_t dev,
+                         int *os_errno, int flag)
+{
+ int ret;
+
+ *os_errno= 0;
+ if((st_mode & S_IFMT) != S_IFBLK && (st_mode & S_IFMT) != S_IFCHR) {
+   if(!(flag & 1))
+     iso_msg_submit(-1, ISO_DEV_NO_CREATION, 0,
+"Device file \"%s\" cannot be created because not of type S_IFBLK or S_IFCHR",
+                    disk_path);
+   return ISO_DEV_NO_CREATION;
+ }
+ st_mode&= (S_IFMT | 07777);
+ ret= mknod(disk_path, st_mode, dev);
+ if(ret == -1) {
+   *os_errno= errno;
+   if(!(flag & 1)) {
+     if(errno > 0) {
+       iso_msg_submit(-1, ISO_DEV_NOT_CREATED, 0,
+                      "Creation of device file \"%s\" failed with %d '%s'",
+                      disk_path, errno, strerror(errno));
+     } else {
+       iso_msg_submit(-1, ISO_DEV_NOT_CREATED, 0,
+                    "Creation of device file \"%s\" failed without error code",
+                      disk_path);
+     }
+   }
+   return ISO_DEV_NOT_CREATED;
+ }
+ return(ISO_SUCCESS);
+}
+
+
+

libisofs/aaip-os-linux.c

@@ -7,7 +7,7 @@
 
  To be included by aaip_0_2.c for Linux
 
- Copyright (c) 2009 - 2024 Thomas Schmitt
+ Copyright (c) 2009 - 2025 Thomas Schmitt
 
  This file is part of the libisofs project; you can redistribute it and/or
  modify it under the terms of the GNU General Public License version 2
@@ -27,6 +27,7 @@
 #include <string.h>
 #include <stdio.h>
 #include <sys/stat.h>
+#include <fcntl.h>
 #include <errno.h>
 
 
@@ -1125,3 +1126,45 @@ int aaip_set_projid(char *path, uint32_t projid, int *os_errno, int flag)
  return(ret);
 }
 
+
+/* -------- API for creating device files in the local filesystem --------- */
+
+
+/* API */
+/* @param flag  bit0= do not issue error messages
+*/
+int iso_local_create_dev(char *disk_path, mode_t st_mode, dev_t dev,
+                         int *os_errno, int flag)
+{
+ int ret;
+
+ *os_errno= 0;
+ if((st_mode & S_IFMT) != S_IFBLK && (st_mode & S_IFMT) != S_IFCHR) {
+   if(!(flag & 1))
+     iso_msg_submit(-1, ISO_DEV_NO_CREATION, 0,
+"Device file \"%s\" cannot be created because not of type S_IFBLK or S_IFCHR",
+                    disk_path);
+   return ISO_DEV_NO_CREATION;
+ }
+ st_mode&= (S_IFMT | 07777);
+ ret= mknod(disk_path, st_mode, dev);
+ if(ret == -1) {
+   *os_errno= errno;
+   if(!(flag & 1)) {
+     if(errno > 0) {
+       iso_msg_submit(-1, ISO_DEV_NOT_CREATED, 0,
+                      "Creation of device file \"%s\" failed with %d '%s'",
+                      disk_path, errno, strerror(errno));
+     } else {
+       iso_msg_submit(-1, ISO_DEV_NOT_CREATED, 0,
+                    "Creation of device file \"%s\" failed without error code",
+                      disk_path);
+     }
+   }
+   return ISO_DEV_NOT_CREATED;
+ }
+ return(ISO_SUCCESS);
+}
+
+
+

libisofs/libisofs.h

@@ -8381,6 +8381,42 @@ int iso_local_set_projid(char *disk_path, uint32_t projid, int *os_errno,
                          int flag);
 
 
+/* -------- API for creating device files in the local filesystem --------- */
+
+/**
+ * Create a device file in the local filesystem.
+ * Equivalent of non-portable and possibly obsolete mknod(2).
+ * Whether this makes sense on modern systems is very questionable. But as
+ * libisofs records device files, it should try to restore them where
+ * device creation might be supported.
+ *
+ * @param disk_path
+ *      Path in the local filesystem where to create the file.
+ * @param st_mode
+ *      File type and permission bits as of man stat(2) field st_mode.
+ *      Possibly supported file types are: S_IFCHR , S_IFBLK
+ * @param dev
+ *      System specific parameters for the new device file. It should have
+ *      been originally obtained by a stat(2) call on a system with compatible
+ *      device parameters.
+ * @param os_errno
+ *      Will get filled with errno if a system call fails.
+ *      Else it will be filled with 0.
+ * @param flag
+ *      Bitfield for control purposes.
+ *      bit0= do not issue error messages
+ * @return
+ *      ISO_SUCCESS or <0 to indicate error.
+ *
+ * @since 1.5.8
+ */
+int iso_local_create_dev(char *disk_path, mode_t st_mode, dev_t dev,
+                         int *os_errno, int flag);
+
+ 
+/* ------------------------------------------------------------------------- */
+
+
 /* Default in case that the compile environment has no macro PATH_MAX.
 */
 #define Libisofs_default_path_maX 4096
@@ -9910,6 +9946,13 @@ int iso_conv_name_chars(IsoWriteOpts *opts, char *name, size_t name_len,
 /** More than 4294967295 bytes of Continuation area    (WARNING,HIGH, -441) */
 #define ISO_INSANE_CE_SIZE          0xD030FE47
 
+/** Creation of device file in local filesystem failed (FAILURE,HIGH, -442) */
+#define ISO_DEV_NOT_CREATED         0xE830FE46
+
+/** Creation of device file type in local filesystem is not enabled
+                                                       (FAILURE,HIGH, -443) */
+#define ISO_DEV_NO_CREATION         0xE830FE45
+
 
 /* Internal developer note: 
    Place new error codes directly above this comment. 

libisofs/libisofs.ver

@@ -386,6 +386,7 @@ local: *;
 };
 
 LIBISOFS6_1.5.8 {
+iso_local_create_dev;
 iso_local_get_lfa_flags;
 iso_local_get_projid;
 iso_local_set_lfa_flags;

libisofs/messages.c

@@ -597,6 +597,10 @@ const char *iso_error_to_msg(int errcode)
         return "Size calculation mismatch with directory record or continuation area";
     case ISO_INSANE_CE_SIZE:
         return "More than 4294967295 bytes of Continuation area";
+    case ISO_DEV_NOT_CREATED:
+        return "Creation of device file in local filesystem failed";
+    case ISO_DEV_NO_CREATION:
+        return "Creation of device file type in local filesystem not enabled";
     default:
         return "Unknown error";
     }