helper/init: Handle compressed modules transparently.

[febootstrap.git] / helper / init.c

diff --git a/helper/init.c b/helper/init.c
index 7b6b94e..447df8e 100644 (file)
--- a/helper/init.c
+++ b/helper/init.c
@@ -19,8 +19,7 @@
 /* This very minimal init "script" goes in the mini-initrd used to
  * boot the ext2-based appliance.  Note we have no shell, so we cannot
  * use system(3) to run external commands.  In fact, we don't have
- * very much at all, except this program, insmod.static, and some
- * kernel modules.
+ * very much at all, except this program, and some kernel modules.
  */
 
 #include <config.h>
@@ -30,17 +29,44 @@
 #include <string.h>
 #include <unistd.h>
 #include <errno.h>
+#include <fcntl.h>
 #include <dirent.h>
 #include <sys/types.h>
 #include <sys/mount.h>
 #include <sys/stat.h>
 #include <sys/wait.h>
 
+#include <asm/unistd.h>
+
+#ifdef HAVE_LIBZ
+#include <zlib.h>
+#endif
+
+extern long init_module (void *, unsigned long, const char *);
+
+/* translation taken from module-init-tools/insmod.c  */
+static const char *moderror(int err)
+{
+  switch (err) {
+  case ENOEXEC:
+    return "Invalid module format";
+  case ENOENT:
+    return "Unknown symbol in module";
+  case ESRCH:
+    return "Module has wrong symbol version";
+  case EINVAL:
+    return "Invalid parameters";
+  default:
+    return strerror(err);
+  }
+}
+
 /* Leave this enabled for now.  When we get more confident in the boot
  * process we can turn this off or make it configurable.
  */
 #define verbose 1
 
+static void mount_proc (void);
 static void print_uptime (void);
 static void insmod (const char *filename);
 static void show_directory (const char *dir);
@@ -50,6 +76,8 @@ static char line[1024];
 int
 main ()
 {
+  mount_proc ();
+
   print_uptime ();
   fprintf (stderr, "febootstrap: ext2 mini initrd starting up\n");
 
@@ -66,12 +94,6 @@ main ()
     exit (EXIT_FAILURE);
   }
 
-  /* A perennial problem is that /sbin/insmod.static is not
-   * executable.  Just make it executable.  It's easier than fixing
-   * everyone's distro.
-   */
-  chmod ("/sbin/insmod.static", 0755);
-
   FILE *fp = fopen ("/modules", "r");
   if (fp == NULL) {
     perror ("fopen: /modules");
@@ -81,7 +103,16 @@ main ()
     size_t n = strlen (line);
     if (n > 0 && line[n-1] == '\n')
       line[--n] = '\0';
-    insmod (line);
+
+    /* XXX Because of the way we construct the module list, the
+     * "modules" file can contain non-existent modules.  Ignore those
+     * for now.  Really we should add them as missing dependencies.
+     * See ext2initrd.c:ext2_make_initrd().
+     */
+    if (access (line, R_OK) == 0)
+      insmod (line);
+    else
+      fprintf (stderr, "skipped %s, module is missing\n", line);
   }
   fclose (fp);
 
@@ -174,27 +205,91 @@ main ()
 static void
 insmod (const char *filename)
 {
+  size_t size;
+
   if (verbose)
-    fprintf (stderr, "febootstrap: insmod %s\n", filename);
+    fprintf (stderr, "febootstrap: internal insmod %s\n", filename);
 
-  pid_t pid = fork ();
-  if (pid == -1) {
-    perror ("insmod: fork");
+#ifdef HAVE_LIBZ
+  gzFile gzfp = gzopen (filename, "rb");
+  int capacity = 64*1024;
+  char *buf = (char *) malloc (capacity);
+  int tmpsize = 8 * 1024;
+  char tmp[tmpsize];
+  int num;
+
+  size = 0;
+
+  if (gzfp == NULL) {
+    fprintf (stderr, "insmod: gzopen failed: %s", filename);
     exit (EXIT_FAILURE);
   }
-
-  if (pid == 0) { /* Child. */
-    execl ("/insmod.static", "insmod.static", filename, NULL);
-    perror ("insmod: execl");
-    _exit (EXIT_FAILURE);
+  while ((num = gzread (gzfp, tmp, tmpsize)) > 0) {
+    if (num > capacity) {
+      buf = (char*) realloc (buf, size*2);
+      capacity = size;
+    }
+    memcpy (buf+size, tmp, num);
+    capacity -= num;
+    size += num;
+  }
+  if (num == -1) {
+    perror ("insmod: gzread");
+    exit (EXIT_FAILURE);
+  }
+  gzclose (gzfp);
+#else
+  int fd = open (filename, O_RDONLY);
+  if (fd == -1) {
+    fprintf (stderr, "insmod: open: %s: %m\n", filename);
+    exit (EXIT_FAILURE);
+  }
+  struct stat st;
+  if (fstat (fd, &st) == -1) {
+    perror ("insmod: fstat");
+    exit (EXIT_FAILURE);
+  }
+  size = st.st_size;
+  char buf[size];
+  size_t offset = 0;
+  do {
+    ssize_t rc = read (fd, buf + offset, size - offset);
+    if (rc == -1) {
+      perror ("insmod: read");
+      exit (EXIT_FAILURE);
+    }
+    offset += rc;
+  } while (offset < size);
+  close (fd);
+#endif
+
+  if (init_module (buf, size, "") != 0) {
+    fprintf (stderr, "insmod: init_module: %s: %s\n", filename, moderror (errno));
+    /* However ignore the error because this can just happen because
+     * of a missing device.
+     */
   }
 
-  /* Parent. */
-  int status;
-  if (wait (&status) == -1 ||
-      WEXITSTATUS (status) != 0)
-    perror ("insmod: wait");
-    /* but ignore the error, some will be because the device is not found */
+#ifdef HAVE_LIBZ
+  free (buf);
+#endif
+}
+
+/* Mount /proc unless it's mounted already. */
+static void
+mount_proc (void)
+{
+  if (access ("/proc/uptime", R_OK) == -1) {
+    mkdir ("/proc", 0755);
+
+    if (verbose)
+      fprintf (stderr, "febootstrap: mounting /proc\n");
+
+    if (mount ("proc", "/proc", "proc", 0, "") == -1) {
+      perror ("mount: /proc");
+      /* Non-fatal. */
+    }
+  }
 }
 
 /* Print contents of /proc/uptime. */
@@ -254,9 +349,9 @@ show_directory (const char *dirname)
   }
 
   while ((d = readdir (dir)) != NULL) {
-    fprintf (stderr, "%5d %c %-16s", d->d_ino, dirtype (d->d_type), d->d_name);
+    fprintf (stderr, "%5lu %c %-16s", d->d_ino, dirtype (d->d_type), d->d_name);
     if (lstat (d->d_name, &statbuf) >= 0) {
-      fprintf (stderr, " %06o %d %d:%d",
+      fprintf (stderr, " %06o %ld %d:%d",
                statbuf.st_mode, statbuf.st_size,
                statbuf.st_uid, statbuf.st_gid);
       if (S_ISLNK (statbuf.st_mode)) {