examples/module: Add support for automounting removable media. This involves a wait for the block driver to become available before performing the mount.

examples/module/module_main.c

@@ -40,9 +40,8 @@
 #include <nuttx/config.h>
 #include <nuttx/compiler.h>
 
-#ifdef CONFIG_EXAMPLES_MODULE_BUILTINFS
-#  include <sys/mount.h>
-#endif
+#include <sys/mount.h>
+#include <sys/stat.h>
 
 #include <sys/boardctl.h>
 #include <stdio.h>
@@ -80,7 +79,7 @@
 #  error "You must select CONFIG_MODULE in your configuration file"
 #endif
 
-#ifdef CONFIG_EXAMPLES_MODULE_BUILTINFS
+#if defined(CONFIG_EXAMPLES_MODULE_BUILTINFS)
 #  if !defined(CONFIG_FS_ROMFS) || !defined(CONFIG_FS_CROMFS)
 #    error "You must select CONFIG_FS_ROMFS or CONFIG_FS_CROMFS in your configuration file"
 #  endif
@@ -91,7 +90,7 @@
 
   /* Describe the ROMFS file system */
 
-#  if defined(CONFIG_EXAMPLES_ELF_CROMFS)
+#  if defined(CONFIG_EXAMPLES_MODULE_CROMFS)
 #    define SECTORSIZE   64
 #    define NSECTORS(b)  (((b)+SECTORSIZE-1)/SECTORSIZE)
 #    define MOUNTPT      "/mnt/romfs"
@@ -103,7 +102,7 @@
 #    ifndef CONFIG_EXAMPLES_MODULE_DEVPATH
 #      define CONFIG_EXAMPLES_MODULE_DEVPATH "/dev/ram0"
 #    endif
-#  elif defined(CONFIG_EXAMPLES_ELF_CROMFS)
+#  elif defined(CONFIG_EXAMPLES_MODULE_CROMFS)
 /* Describe the CROMFS file system */
 
 #    define MOUNTPT      "/mnt/cromfs"
@@ -111,8 +110,13 @@
 
 #  define BINDIR         MOUNTPT
 
+#elif defined(CONFIG_EXAMPLES_MODULE_FSMOUNT)
+#  define MOUNTPT        "/mnt/" CONFIG_EXAMPLES_MODULE_FSTYPE
+#  define BINDIR         MOUNTPT
+
 #else
 #  define BINDIR         CONFIG_EXAMPLES_MODULE_BINDIR
+
 #endif /* CONFIG_EXAMPLES_MODULE_BUILTINFS */
 
 /****************************************************************************
@@ -143,6 +147,9 @@ int module_main(int argc, char *argv[])
 #endif
 {
   struct boardioc_symtab_s symdesc;
+#ifdef CONFIG_EXAMPLES_MODULE_FSREMOVEABLE
+  struct stat buf;
+#endif
   FAR void *handle;
   char buffer[128];
   ssize_t nbytes;
@@ -161,7 +168,7 @@ int module_main(int argc, char *argv[])
     }
 
 #ifdef CONFIG_EXAMPLES_MODULE_BUILTINFS
-#if defined(CONFIG_EXAMPLES_ELF_ROMFS)
+#if defined(CONFIG_EXAMPLES_MODULE_ROMFS)
   /* Create a ROM disk for the ROMFS filesystem */
 
   printf("main: Registering romdisk at /dev/ram%d\n",
@@ -206,7 +213,7 @@ int module_main(int argc, char *argv[])
       exit(EXIT_FAILURE);
     }
 
-#elif defined(CONFIG_EXAMPLES_ELF_CROMFS)
+#elif defined(CONFIG_EXAMPLES_MODULE_CROMFS)
   /* Mount the CROMFS file system */
 
   printf("Mounting CROMFS filesystem at target=%s\n", MOUNTPT);
@@ -217,7 +224,58 @@ int module_main(int argc, char *argv[])
       errmsg("ERROR: mount(%s, cromfs) failed: %d\n", MOUNTPT, errno);
     }
 
-#endif /* CONFIG_EXAMPLES_ELF_ROMFS */
+#endif /* CONFIG_EXAMPLES_MODULE_ROMFS */
+#elif defined(CONFIG_EXAMPLES_MODULE_EXTERN)
+  /* An external file system is being used */
+
+#if defined(CONFIG_EXAMPLES_MODULE_FSMOUNT)
+#if defined(CONFIG_EXAMPLES_MODULE_FSREMOVEABLE)
+  /* The file system is removable, wait until the block driver is available */
+
+  do
+    {
+      ret = stat(CONFIG_EXAMPLES_MODULE_DEVPATH, &buf);
+      if (ret < 0)
+        {
+          int errcode = errno;
+          if (errcode == ENOENT)
+            {
+              printf("%s does not exist.  Waiting...\n",
+                     CONFIG_EXAMPLES_MODULE_DEVPATH);
+              sleep(1);
+            }
+          else
+            {
+              printf("ERROR: stat(%s) failed: %d  Aborting...\n",
+                     CONFIG_EXAMPLES_MODULE_DEVPATH, errcode);
+              exit(EXIT_FAILURE);
+            }
+        }
+      else if (!S_ISBLK(buf.st_mode))
+        {
+          printf("ERROR: stat(%s) exists but is not a block driver: %04x\n",
+                 CONFIG_EXAMPLES_MODULE_DEVPATH, buf.st_mode);
+          exit(EXIT_FAILURE);
+        }
+    }
+  while (ret < 0);
+#endif  /* CONFIG_EXAMPLES_MODULE_FSREMOVEABLE */
+
+  /* Mount the external file system */
+
+  message("Mounting %s filesystem at target=%s\n",
+          CONFIG_EXAMPLES_MODULE_FSTYPE, MOUNTPT);
+
+  ret = mount(CONFIG_EXAMPLES_MODULE_DEVPATH, MOUNTPT,
+              CONFIG_EXAMPLES_MODULE_FSTYPE, MS_RDONLY, NULL);
+  if (ret < 0)
+    {
+      errmsg("ERROR: mount(%s, %s, %s) failed: %d\n",\
+             CONFIG_EXAMPLES_MODULE_DEVPATH, CONFIG_EXAMPLES_MODULE_FSTYPE,
+             MOUNTPT, errno);
+    }
+
+#endif
 #endif /* CONFIG_EXAMPLES_MODULE_BUILTINFS */
 
   /* Install the character driver  */