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-rw-r--r--boot/boot_script.c861
-rw-r--r--boot/boot_script.h91
2 files changed, 952 insertions, 0 deletions
diff --git a/boot/boot_script.c b/boot/boot_script.c
new file mode 100644
index 00000000..ca71ccc3
--- /dev/null
+++ b/boot/boot_script.c
@@ -0,0 +1,861 @@
+/* Script parser for Mach. */
+
+#include <mach/mach_types.h>
+#include <mach/message.h>
+#include "boot_script.h"
+
+/* This structure describes a command. */
+struct cmd
+{
+ /* Path of executable. */
+ char *path;
+
+ /* Task port. */
+ mach_port_t task;
+
+ /* Argument list. */
+ struct arg **args;
+
+ /* Amount allocated for `args'. */
+ int args_alloc;
+
+ /* Next available slot in `args'. */
+ int args_index;
+
+ /* List of functions that want to be run on command execution. */
+ struct sym **exec_funcs;
+
+ /* Amount allocated for `exec_funcs'. */
+ int exec_funcs_alloc;
+
+ /* Next available slot in `exec_funcs'. */
+ int exec_funcs_index;
+};
+
+/* This structure describes a symbol. */
+struct sym
+{
+ /* Symbol name. */
+ char *name;
+
+ /* Pointer to function that returns symbol value.
+ The function should return 0 on success, non-zero otherwise. */
+ int (*func) (struct cmd *cmd, int *val);
+
+ /* Type of value returned by function. */
+ int type;
+
+ /* Symbol value. */
+ int val;
+
+ /* If set, don't create an argument if the symbol
+ appears by itself in an expression. */
+ int no_arg;
+
+ /* If set, execute function at the time of command execution,
+ not during parsing. A function with this field set must
+ also have `no_arg' set. Also, the function's `val' argument
+ will always be NULL. */
+ int run_on_exec;
+};
+
+/* Type of values symbols can have. */
+#define VAL_NONE 0 /* none */
+#define VAL_STR 1 /* string */
+#define VAL_PORT 2 /* port */
+#define VAL_SYM 3 /* symbol table entry */
+
+/* This structure describes an argument. */
+struct arg
+{
+ /* Argument text copied verbatim. 0 if none. */
+ char *text;
+
+ /* Type of value assigned. 0 if none. */
+ int type;
+
+ /* Argument value. */
+ int val;
+};
+
+/* List of commands. */
+static struct cmd **cmds = 0;
+
+/* Amount allocated for `cmds'. */
+static int cmds_alloc = 0;
+
+/* Next available slot in `cmds'. */
+static int cmds_index = 0;
+
+/* Symbol table. */
+static struct sym **symtab = 0;
+
+/* Amount allocated for `symtab'. */
+static int symtab_alloc = 0;
+
+/* Next available slot in `symtab'. */
+static int symtab_index = 0;
+
+void memset (void *str, char c, int size);
+
+/* Create a task. */
+static int
+create_task (struct cmd *cmd, int *val)
+{
+ cmd->task = boot_script_task_create ();
+ if (cmd->task == 0)
+ return BOOT_SCRIPT_MACH_ERROR;
+ boot_script_task_suspend (cmd->task);
+ *val = (int) cmd->task;
+ return 0;
+}
+
+/* Resume a task. */
+static int
+resume_task (struct cmd *cmd, int *val)
+{
+ if (boot_script_task_resume (cmd->task))
+ return BOOT_SCRIPT_MACH_ERROR;
+ return 0;
+}
+
+/* Return a send right to the host port. */
+static int
+get_host_port (struct cmd *cmd, int *val)
+{
+ *val = (int) boot_script_host_port;
+ return 0;
+}
+
+/* Return a send right to the master device port. */
+static int
+get_device_port (struct cmd *cmd, int *val)
+{
+ *val = (int) boot_script_device_port;
+ return 0;
+}
+
+/* Return the root device name. */
+static int
+get_root_device (struct cmd *cmd, int *val)
+{
+ *val = (int) boot_script_root_device;
+ return 0;
+}
+
+/* Set the bootstrap port for a task. */
+static int
+set_bootstrap_port (struct cmd *cmd, int *val)
+{
+ boot_script_set_bootstrap_port (cmd->task, boot_script_bootstrap_port);
+ return 0;
+}
+
+/* List of builtin symbols. */
+static struct sym builtin_symbols[] =
+{
+ { "task-create", create_task, VAL_PORT, 0, 1, 0 },
+ { "task-resume", resume_task, VAL_NONE, 0, 1, 1 },
+ { "host-port", get_host_port, VAL_PORT, 0, 0, 0 },
+ { "device-port", get_device_port, VAL_PORT, 0, 0, 0 },
+ { "bootstrap-port", set_bootstrap_port, VAL_NONE, 0, 1, 0 },
+ { "root-device", get_root_device, VAL_STR, 0, 0, 0 }
+};
+#define NUM_BUILTIN (sizeof (builtin_symbols) / sizeof (builtin_symbols[0]))
+
+/* Free CMD and all storage associated with it.
+ If ABORTING is set, terminate the task associated with CMD,
+ otherwise just deallocate the send right. */
+static void
+free_cmd (struct cmd *cmd, int aborting)
+{
+ if (cmd->task)
+ {
+ if (aborting)
+ boot_script_task_terminate (cmd->task);
+ else
+ boot_script_port_deallocate (boot_script_task_port, cmd->task);
+ }
+ if (cmd->args)
+ {
+ int i;
+
+ for (i = 0; i < cmd->args_index; i++)
+ boot_script_free (cmd->args[i], sizeof (struct arg));
+ boot_script_free (cmd->args, cmd->args_alloc * sizeof (struct arg *));
+ }
+ if (cmd->exec_funcs)
+ boot_script_free (cmd->exec_funcs,
+ cmd->exec_funcs_alloc * sizeof (struct sym *));
+ boot_script_free (cmd, sizeof (struct cmd));
+}
+
+/* Free all storage allocated by the parser.
+ If ABORTING is set, terminate all tasks. */
+static void
+cleanup (int aborting)
+{
+ int i;
+
+ for (i = 0; i < cmds_index; i++)
+ free_cmd (cmds[i], aborting);
+ boot_script_free (cmds, cmds_alloc * sizeof (struct cmd *));
+ cmds = 0;
+ cmds_index = cmds_alloc = 0;
+
+ for (i = 0; i < symtab_index; i++)
+ boot_script_free (symtab[i], sizeof (struct sym));
+ boot_script_free (symtab, symtab_alloc * sizeof (struct sym *));
+ symtab = 0;
+ symtab_index = symtab_alloc = 0;
+}
+
+/* Add PTR to the list of pointers PTR_LIST, which
+ currently has ALLOC amount of space allocated to it, and
+ whose next available slot is INDEX. If more space
+ needs to to allocated, INCR is the amount by which
+ to increase it. Return 0 on success, non-zero otherwise. */
+static int
+add_list (void *ptr, void ***ptr_list, int *alloc, int *index, int incr)
+{
+ if (*index == *alloc)
+ {
+ void **p;
+
+ *alloc += incr;
+ p = boot_script_malloc (*alloc * sizeof (void *));
+ if (! p)
+ {
+ *alloc -= incr;
+ return 1;
+ }
+ if (*ptr_list)
+ {
+ memcpy (p, *ptr_list, *index * sizeof (void *));
+ boot_script_free (*ptr_list, *index * sizeof (void *));
+ }
+ *ptr_list = p;
+ }
+ *(*ptr_list + *index) = ptr;
+ *index += 1;
+ return 0;
+}
+
+/* Create an argument with TEXT, value type TYPE, and value VAL.
+ Add the argument to the argument list of CMD. */
+static struct arg *
+add_arg (struct cmd *cmd, char *text, int type, int val)
+{
+ struct arg *arg;
+
+ arg = boot_script_malloc (sizeof (struct arg));
+ if (arg)
+ {
+ arg->text = text;
+ arg->type = type;
+ arg->val = val;
+ if (add_list (arg, (void ***) &cmd->args,
+ &cmd->args_alloc, &cmd->args_index, 5))
+ {
+ boot_script_free (arg, sizeof (struct arg));
+ return 0;
+ }
+ }
+ return arg;
+}
+
+/* Search for the symbol NAME in the symbol table. */
+static struct sym *
+sym_lookup (char *name)
+{
+ int i;
+
+ for (i = 0; i < symtab_index; i++)
+ if (! strcmp (name, symtab[i]->name))
+ return symtab[i];
+ return 0;
+}
+
+/* Create an entry for symbol NAME in the symbol table. */
+static struct sym *
+sym_enter (char *name)
+{
+ struct sym *sym;
+
+ sym = boot_script_malloc (sizeof (struct sym));
+ if (sym)
+ {
+ memset (sym, 0, sizeof (struct sym));
+ sym->name = name;
+ if (add_list (sym, (void ***) &symtab, &symtab_alloc, &symtab_index, 20))
+ {
+ boot_script_free (sym, sizeof (struct sym));
+ return 0;
+ }
+ }
+ return sym;
+}
+
+/* Parse the command line CMDLINE. */
+int
+boot_script_parse_line (char *cmdline)
+{
+ char *p, *q;
+ int error;
+ struct cmd *cmd;
+ struct arg *arg;
+
+ /* Extract command name. Ignore line if it lacks a command. */
+ for (p = cmdline; *p == ' ' || *p == '\t'; p++)
+ ;
+ for (q = p; *q && *q != ' ' && *q != '\t' && *q != '\n'; q++)
+ ;
+ if (p == q)
+ return 0;
+ *q = '\0';
+
+ /* Allocate a command structure. */
+ cmd = boot_script_malloc (sizeof (struct cmd));
+ if (! cmd)
+ return BOOT_SCRIPT_NOMEM;
+ memset (cmd, 0, sizeof (struct cmd));
+ cmd->path = p;
+ p = q + 1;
+
+ for (arg = 0;;)
+ {
+ if (! arg)
+ {
+ /* Skip whitespace. */
+ while (*p == ' ' || *p == '\t')
+ p++;
+
+ /* End of command line. */
+ if (! *p || *p == '\n')
+ {
+ /* Add command to list. */
+ if (add_list (cmd, (void ***) &cmds,
+ &cmds_alloc, &cmds_index, 10))
+ {
+ error = BOOT_SCRIPT_NOMEM;
+ goto bad;
+ }
+ return 0;
+ }
+ }
+
+ /* Look for a symbol. */
+ if (arg || (*p == '$' && *(p + 1) == '{'))
+ {
+ int saw_assignment = 0;
+ struct sym *sym = 0;
+
+ for (p += 2;;)
+ {
+ char c;
+ int i, val, type, is_builtin = 0;
+ struct sym *s;
+
+ /* Parse symbol name. */
+ for (q = p; *q && *q != '\n' && *q != '}' && *q != '='; q++)
+ ;
+ if (p == q || ! *q || *q == '\n')
+ {
+ error = BOOT_SCRIPT_SYNTAX_ERROR;
+ goto bad;
+ }
+ c = *q;
+ *q = '\0';
+
+ /* See if this is a builtin symbol. */
+ for (i = 0; i < NUM_BUILTIN; i++)
+ if (! strcmp (p, builtin_symbols[i].name))
+ break;
+
+ if (i < NUM_BUILTIN)
+ {
+ is_builtin = 1;
+ s = &builtin_symbols[i];
+
+ /* Check that assignment is valid. */
+ if (c != '}' || ((arg || sym) && s->type == VAL_NONE))
+ {
+ error = BOOT_SCRIPT_INVALID_ASG;
+ goto bad;
+ }
+
+ if (! s->run_on_exec)
+ {
+ error = (*s->func) (cmd, &val);
+ if (error)
+ goto bad;
+ type = s->type;
+ }
+ else
+ {
+ if (add_list (s, (void ***) &cmd->exec_funcs,
+ &cmd->exec_funcs_alloc,
+ &cmd->exec_funcs_index, 5))
+ {
+ error = BOOT_SCRIPT_NOMEM;
+ goto bad;
+ }
+ type = VAL_NONE;
+ goto out;
+ }
+ }
+ else
+ {
+ /* Look up symbol in symbol table.
+ If no entry exists, create one. */
+ s = sym_lookup (p);
+ if (! s)
+ {
+ s = sym_enter (p);
+ if (! s)
+ {
+ error = BOOT_SCRIPT_NOMEM;
+ goto bad;
+ }
+ }
+ type = VAL_SYM;
+ val = (int) s;
+ }
+
+ if (sym)
+ {
+ sym->type = type;
+ sym->val = val;
+ }
+ else if (arg)
+ {
+ arg->type = type;
+ arg->val = val;
+ }
+
+ out:
+ p = q + 1;
+ if (c == '}')
+ {
+ /* Create an argument if necessary.
+ We create an argument if the symbol appears
+ in the expression by itself, and it's `no_arg'
+ field is 0.
+
+ NOTE: This is temporary till the boot filesystem
+ servers support arguments. When that happens,
+ symbol values will only be printed if they're
+ associated with an argument. */
+ if (! arg && ! saw_assignment && ! s->no_arg)
+ {
+ struct arg *a;
+
+ if (is_builtin)
+ a = add_arg (cmd, 0, type, val);
+ else
+ a = add_arg (cmd, 0, VAL_SYM, (int) s);
+ if (! a)
+ {
+ error = BOOT_SCRIPT_NOMEM;
+ goto bad;
+ }
+ }
+ arg = 0;
+ break;
+ }
+ else
+ saw_assignment = 1;
+ if (! is_builtin)
+ sym = s;
+ }
+ }
+ else
+ {
+ char c;
+
+ /* Command argument. Just copy the text. */
+ for (q = p;; q++)
+ {
+ if (! *q || *q == ' ' || *q == '\t' || *q == '\n')
+ break;
+ if (*q == '$' && *(q + 1) == '{')
+ break;
+ }
+ c = *q;
+ *q = '\0';
+
+ /* Add argument to list. */
+ arg = add_arg (cmd, p, VAL_NONE, 0);
+ if (! arg)
+ {
+ error = BOOT_SCRIPT_NOMEM;
+ goto bad;
+ }
+ if (c == '$')
+ p = q;
+ else
+ {
+ if (c)
+ p = q + 1;
+ else
+ p = q;
+ arg = 0;
+ }
+ }
+ }
+
+ bad:
+ free_cmd (cmd, 1);
+ cleanup (1);
+ return error;
+}
+
+/* Ensure that the command line buffer can accommodate LEN bytes of space. */
+#define CHECK_CMDLINE_LEN(len) \
+{ \
+ if (cmdline_alloc - cmdline_index < len) \
+ { \
+ char *ptr; \
+ int alloc; \
+ alloc = cmdline_alloc + len - (cmdline_alloc - cmdline_index) + 100; \
+ ptr = boot_script_malloc (alloc); \
+ if (! ptr) \
+ { \
+ error = BOOT_SCRIPT_NOMEM; \
+ goto done; \
+ } \
+ memcpy (ptr, cmdline, cmdline_index); \
+ boot_script_free (cmdline, cmdline_alloc); \
+ cmdline = ptr; \
+ cmdline_alloc = alloc; \
+ } \
+}
+
+/* Execute commands previously parsed. */
+int
+boot_script_exec ()
+{
+ int cmd_index;
+
+ for (cmd_index = 0; cmd_index < cmds_index; cmd_index++)
+ {
+ char **argv, *cmdline;
+ int i, argc, cmdline_alloc;
+ int cmdline_index, error, arg_index;
+ struct cmd *cmd = cmds[cmd_index];
+
+ /* Skip command if it doesn't have an associated task. */
+ if (cmd->task == 0)
+ continue;
+
+ /* Allocate a command line and copy command name. */
+ cmdline_index = strlen (cmd->path) + 1;
+ cmdline_alloc = cmdline_index + 100;
+ cmdline = boot_script_malloc (cmdline_alloc);
+ if (! cmdline)
+ {
+ cleanup (1);
+ return BOOT_SCRIPT_NOMEM;
+ }
+ memcpy (cmdline, cmd->path, cmdline_index);
+
+ /* Allocate argument vector. */
+ argv = boot_script_malloc (sizeof (char *) * (cmd->args_index + 1));
+ if (! argv)
+ {
+ boot_script_free (cmdline, cmdline_alloc);
+ cleanup (1);
+ return BOOT_SCRIPT_NOMEM;
+ }
+ argv[0] = cmdline;
+ argc = 1;
+
+ /* Build arguments. */
+ for (arg_index = 0; arg_index < cmd->args_index; arg_index++)
+ {
+ struct arg *arg = cmd->args[arg_index];
+
+ /* Copy argument text. */
+ if (arg->text)
+ {
+ int len = strlen (arg->text);
+
+ if (arg->type == VAL_NONE)
+ len++;
+ CHECK_CMDLINE_LEN (len);
+ memcpy (cmdline + cmdline_index, arg->text, len);
+ argv[argc++] = &cmdline[cmdline_index];
+ cmdline_index += len;
+ }
+
+ /* Add value of any symbol associated with this argument. */
+ if (arg->type != VAL_NONE)
+ {
+ char *p = 0, buf[50];
+ int len = 0;
+
+ if (arg->type == VAL_SYM)
+ {
+ struct sym *sym = (struct sym *) arg->val;
+
+ /* Resolve symbol value. */
+ while (sym->type == VAL_SYM)
+ sym = (struct sym *) sym->val;
+ if (sym->type == VAL_NONE)
+ {
+ error = BOOT_SCRIPT_UNDEF_SYM;
+ goto done;
+ }
+ arg->type = sym->type;
+ arg->val = sym->val;
+ }
+
+ /* Print argument value. */
+ switch (arg->type)
+ {
+ case VAL_STR:
+ p = (char *) arg->val;
+ len = strlen (p);
+ break;
+
+ case VAL_PORT:
+ /* Insert send right. */
+ if ((boot_script_port_insert_right
+ (cmd->task, (mach_port_t) arg->val,
+ (mach_port_t) arg->val, MACH_MSG_TYPE_COPY_SEND)))
+ {
+ error = BOOT_SCRIPT_MACH_ERROR;
+ goto done;
+ }
+
+ i = arg->val;
+ p = buf + sizeof (buf);
+ len = 0;
+ do
+ {
+ *--p = i % 10 + '0';
+ len++;
+ }
+ while (i /= 10);
+ break;
+ }
+ len++;
+ CHECK_CMDLINE_LEN (len);
+ memcpy (cmdline + cmdline_index, p, len - 1);
+ *(cmdline + cmdline_index + len - 1) = '\0';
+ if (! arg->text)
+ argv[argc++] = &cmdline[cmdline_index];
+ cmdline_index += len;
+ }
+ }
+
+ /* Terminate argument vector. */
+ argv[argc] = 0;
+
+ /* Execute the command. */
+ if (boot_script_exec_cmd (cmd->task, cmd->path,
+ argc, argv, cmdline, cmdline_index))
+ {
+ error = BOOT_SCRIPT_EXEC_ERROR;
+ goto done;
+ }
+
+ error = 0;
+
+ done:
+ boot_script_free (cmdline, cmdline_alloc);
+ boot_script_free (argv, (cmd->args_index + 1) * sizeof (char *));
+ if (error)
+ {
+ cleanup (1);
+ return error;
+ }
+ }
+
+ for (cmd_index = 0; cmd_index < cmds_index; cmd_index++)
+ {
+ int i;
+ struct cmd *cmd = cmds[cmd_index];
+
+ if (cmd->task)
+ /* Execute functions that want to be run on exec. */
+ for (i = 0; i < cmd->exec_funcs_index; i++)
+ {
+ struct sym *sym = cmd->exec_funcs[i];
+ int error = (*sym->func) (cmd, 0);
+ if (error)
+ {
+ cleanup (1);
+ return error;
+ }
+ }
+ }
+
+ cleanup (0);
+ return 0;
+}
+
+/* Return a string describing ERR. */
+char *
+boot_script_error_string (int err)
+{
+ switch (err)
+ {
+ case BOOT_SCRIPT_NOMEM:
+ return "no memory";
+
+ case BOOT_SCRIPT_SYNTAX_ERROR:
+ return "syntax error";
+
+ case BOOT_SCRIPT_INVALID_ASG:
+ return "invalid variable in assignment";
+
+ case BOOT_SCRIPT_MACH_ERROR:
+ return "mach error";
+
+ case BOOT_SCRIPT_UNDEF_SYM:
+ return "undefined symbol";
+
+ case BOOT_SCRIPT_EXEC_ERROR:
+ return "exec error";
+ }
+ return 0;
+}
+
+#ifdef BOOT_SCRIPT_TEST
+#include <mach.h>
+#include <stdio.h>
+
+extern void *malloc (int size);
+extern void free (void *ptr);
+
+char *boot_script_root_device = "hd0a";
+mach_port_t boot_script_task_port;
+mach_port_t boot_script_host_port;
+mach_port_t boot_script_device_port;
+mach_port_t boot_script_bootstrap_port = MACH_PORT_NULL;
+
+void *
+boot_script_malloc (int size)
+{
+ return malloc (size);
+}
+
+void
+boot_script_free (void *ptr, int size)
+{
+ free (ptr);
+}
+
+mach_port_t
+boot_script_task_create ()
+{
+ mach_port_t task;
+
+ if (task_create (mach_task_self (), FALSE, &task))
+ return 0;
+ return task;
+}
+
+void
+boot_script_task_terminate (mach_port_t task)
+{
+ task_terminate (task);
+}
+
+void
+boot_script_task_suspend (mach_port_t task)
+{
+ task_suspend (task);
+}
+
+int
+boot_script_task_resume (mach_port_t task)
+{
+ mach_port_t bootport;
+
+ task_get_bootstrap_port (task, &bootport);
+ printf ("bootstrap port %d\n", bootport);
+ printf ("boot_script_task_resume()\n");
+ return 0;
+}
+
+void
+boot_script_port_deallocate (mach_port_t task, mach_port_t port)
+{
+ mach_port_deallocate (task, port);
+}
+
+int
+boot_script_port_insert_right (mach_port_t task, mach_port_t name,
+ mach_port_t port, mach_msg_type_name_t right)
+{
+ if (mach_port_insert_right (task, name, port, right))
+ return 1;
+ return 0;
+}
+
+void
+boot_script_set_bootstrap_port (mach_port_t task, mach_port_t port)
+{
+ task_set_bootstrap_port (task, port);
+}
+
+int
+boot_script_exec_cmd (mach_port_t task, char *path, int argc,
+ char **argv, char *strings, int stringlen)
+{
+ int i;
+
+ for (i = 0; i < argc; i++)
+ printf ("%s ", argv[i]);
+ printf ("\n");
+ return 0;
+}
+
+void
+main (int argc, char **argv)
+{
+ char buf[500], *p;
+ int len;
+ FILE *fp;
+
+ if (argc < 2)
+ {
+ fprintf (stderr, "Usage: %s <script>\n", argv[0]);
+ exit (1);
+ }
+ fp = fopen (argv[1], "r");
+ if (! fp)
+ {
+ fprintf (stderr, "Can't open %s\n", argv[1]);
+ exit (1);
+ }
+ boot_script_task_port = mach_task_self ();
+ boot_script_host_port = task_by_pid (-1);
+ boot_script_device_port = task_by_pid (-2);
+ if (! boot_script_host_port || ! boot_script_device_port)
+ {
+ fprintf (stderr, "Unable to get privileged ports\n");
+ exit (1);
+ }
+ p = buf;
+ len = sizeof (buf);
+ while (fgets (p, len, fp))
+ {
+ int i, err;
+
+ i = strlen (p) + 1;
+ err = boot_script_parse_line (p);
+ if (err)
+ {
+ fprintf (stderr, "error %s\n", boot_script_error_string (err));
+ exit (1);
+ }
+ p += i;
+ len -= i;
+ }
+ boot_script_exec ();
+ exit (0);
+}
+#endif /* BOOT_SCRIPT_TEST */
diff --git a/boot/boot_script.h b/boot/boot_script.h
new file mode 100644
index 00000000..88a6bf49
--- /dev/null
+++ b/boot/boot_script.h
@@ -0,0 +1,91 @@
+/* Error codes returned by boot_script_parse_line()
+ and boot_script_exec_cmd(). */
+#define BOOT_SCRIPT_NOMEM 1
+#define BOOT_SCRIPT_SYNTAX_ERROR 2
+#define BOOT_SCRIPT_INVALID_ASG 3
+#define BOOT_SCRIPT_MACH_ERROR 4
+#define BOOT_SCRIPT_UNDEF_SYM 5
+#define BOOT_SCRIPT_EXEC_ERROR 6
+
+/* The user must define this variable. The root device name.
+ This must be initialized prior to calling the parser. */
+extern char *boot_script_root_device;
+
+/* The user must define this variable. The task port of the program. */
+extern mach_port_t boot_script_task_port;
+
+/* The user must define this variable. Send right to the host port. */
+extern mach_port_t boot_script_host_port;
+
+/* The user must define this variable. Send right to the
+ master device port. */
+extern mach_port_t boot_script_device_port;
+
+/* The user must define this variable. Send right to the
+ the bootstrap port. */
+extern mach_port_t boot_script_bootstrap_port;
+
+/* The user must define this function. Allocate SIZE bytes of memory
+ and return a pointer to it. */
+void *boot_script_malloc (int size);
+
+/* The user must define this function. Free SIZE bytes of memory
+ named by PTR that was previously allocated by boot_script_malloc(). */
+void boot_script_free (void *ptr, int size);
+
+/* The user must define this function. Create a new task and
+ return a send right to it presumably using task_create().
+ Return 0 on error. */
+mach_port_t boot_script_task_create (void);
+
+/* The user must define this function. Terminate the task whose
+ send right is TASK presumably using task_terminate(). */
+void boot_script_task_terminate (mach_port_t task);
+
+/* The user must define this function. Suspend TASK presumably
+ using task_suspend(). */
+void boot_script_task_suspend (mach_port_t task);
+
+/* The user must define this function. Resume TASK presumably
+ using task_resume(). Return 0 on success, non-zero otherwise. */
+int boot_script_task_resume (mach_port_t task);
+
+/* The user must define this function. Deallocate a send right to PORT
+ in the TASK presumably using mach_port_deallocate(). */
+void boot_script_port_deallocate (mach_port_t task, mach_port_t port);
+
+/* The user must define this function. Insert the specified RIGHT to
+ the PORT in the current task into TASK with NAME, presumably using
+ mach_port_insert_right(). RIGHT can take any value allowed by
+ mach_port_insert_right(). Return 0 for success, non-zero otherwise. */
+int boot_script_port_insert_right (mach_port_t task,
+ mach_port_t name, mach_port_t port,
+ mach_msg_type_name_t right);
+
+/* The user must define this function. Set the bootstrap port for TASK. */
+void boot_script_set_bootstrap_port (mach_port_t task, mach_port_t port);
+
+/* The user must define this function. Load the image of the
+ executable specified by PATH in TASK. Create a thread
+ in TASK and point it at the executable's entry point. Initialize
+ TASK's stack with argument vector ARGV of length ARGC whose
+ strings are STRINGS. STRINGS has length STRINGLEN.
+ Return 0 for success, non-zero otherwise. */
+int boot_script_exec_cmd (mach_port_t task, char *path, int argc,
+ char **argv, char *strings, int stringlen);
+
+/* Parse the command line LINE. This causes the command line to be
+ converted into an internal format. Returns 0 for success, non-zero
+ otherwise.
+
+ NOTE: The parser writes into the line so it must not be a string constant.
+ It is also the responsibility of the caller not to deallocate the line
+ across calls to the parser. */
+int boot_script_parse_line (char *cmdline);
+
+/* Execute the command lines prevously parsed.
+ Returns 0 for success, non-zero otherwise. */
+int boot_script_exec (void);
+
+/* Returns a string describing the error ERR. */
+char *boot_script_error_string (int err);