Progress on executing test0 from memfs file as an elf.

Elf is recognised OK, but somehow section table is not read correctly.

conts/posix/mm0/include/exec.h

@@ -9,7 +9,7 @@
 /*
  * This presents extra executable file information that is
  * not present in the tcb, in a generic format.
- */ 
+ */
 struct exec_file_desc {
 	unsigned long text_offset;	/* File offset of text section */
 	unsigned long data_offset;	/* File offset of data section */

conts/posix/mm0/include/init.h

@@ -34,6 +34,6 @@ void init(void);
 /* TODO: Remove this stuff from here. */
 int init_devzero(void);
 struct vm_file *get_devzero(void);
-int init_boot_files(struct initdata *initdata);
+int init_execve(char *path);
 
 #endif /* __MM_INIT_H__ */

conts/posix/mm0/mm/execve.c

@@ -1,4 +1,4 @@
-/*
+/* It is safe when argc = 0 *//*
  * Program execution
  *
  * Copyright (C) 2008 Bahadir Balban
@@ -19,7 +19,8 @@
 #include <task.h>
 #include <exit.h>
 #include <lib/elf/elf.h>
-
+#include <init.h>
+#include <stat.h>
 
 /*
  * Probes and parses the low-level executable file format and creates a
@@ -33,6 +34,77 @@ int task_setup_from_executable(struct vm_file *vmfile, struct tcb *task,
 	return elf_parse_executable(task, vmfile, efd);
 }
 
+int init_execve(char *filepath)
+{
+	unsigned long vnum, length;
+	struct vm_file *vmfile;
+	struct exec_file_desc efd;
+	struct tcb *new_task;
+	struct task_ids ids = {
+		.tid = TASK_ID_INVALID,
+		.spid = TASK_ID_INVALID,
+		.tgid = TASK_ID_INVALID
+	};
+	struct args_struct args = { .argc = 0 }; /* It is safe when argc = 0 */
+	struct args_struct env = { .argc = 0 }; /* It is safe when argc = 0 */
+	//struct tcb *self = find_task(self_tid());
+	// int fd;
+	int err;
+
+	/* Get file info from vfs */
+	if ((err = vfs_open_bypath(filepath, &vnum, &length)) < 0)
+		return err;
+
+	/* Create and get the file structure */
+	if (IS_ERR(vmfile = do_open2(0, 0, vnum, length)))
+		return (int)vmfile;
+
+#if 0
+	if ((fd = sys_open(self, filepath,
+			   O_RDONLY, 0)) < 0) {
+		printf("FATAL: Could not open file "
+		       "to execute initial task.\n");
+		BUG();
+	}
+#endif
+
+	if (IS_ERR(new_task = task_create(0, &ids,
+					  THREAD_NEW_SPACE,
+					  TCB_NO_SHARING))) {
+		vm_file_put(vmfile); /* FIXME: sys_close() ??? */
+		return (int)new_task;
+	}
+
+	/* Fill and validate tcb memory segment markers from executable file */
+	if ((err = task_setup_from_executable(vmfile, new_task, &efd)) < 0) {
+		vm_file_put(vmfile);
+		kfree(new_task);
+		return err;
+	}
+
+	/* Map task's new segment markers as virtual memory regions */
+	if ((err = task_mmap_segments(new_task, vmfile,
+				      &efd, &args, &env)) < 0) {
+		vm_file_put(vmfile);
+		kfree(new_task);
+		return err;
+	}
+
+	/* Set up task registers via exchange_registers() */
+	task_setup_registers(new_task, 0,
+			     new_task->args_start,
+			     new_task->pagerid);
+
+	/* Add new task to global list */
+	global_add_task(new_task);
+
+	/* Start the task */
+	task_start(new_task);
+
+	return 0;
+}
+
+
 int do_execve(struct tcb *sender, char *filename, struct args_struct *args,
 	      struct args_struct *env)
 {

conts/posix/mm0/mm/file.c

@@ -103,7 +103,7 @@ void print_vnode(struct vnode *v)
 int vfs_open_bypath(const char *pathname, unsigned long *vnum, unsigned long *length)
 {
 	struct pathdata *pdata;
-	struct tcb *task;
+	struct tcb *task = 0;
 	struct vnode *v;
 	int retval;
 

conts/posix/mm0/mm/init.c

@@ -436,14 +436,6 @@ void init_physmem(void)
 	init_page_allocator(membank[0].free, membank[0].end);
 }
 
-void init_execve(char *path)
-{
-	/*
-	 * Find executable, and execute it by creating a new process
-	 * rather than replacing the current image (which is the pager!)
-	 */
-}
-
 /*
  * To be removed later: This file copies in-memory elf image to the
  * initialized and formatted in-memory memfs filesystem.

conts/posix/mm0/mm/task.c

@@ -411,7 +411,7 @@ struct tcb *task_create(struct tcb *parent, struct task_ids *ids,
 			task->parent = parent;
 		}
 	} else {
-		struct tcb *pager = find_task(PAGER_TID);
+		struct tcb *pager = find_task(self_tid());
 
 		/* Initialise vfs specific fields. */
 		task->fs_data->rootdir = vfs_root.pivot;

conts/posix/test0/SConscript

@@ -9,7 +9,7 @@ sys.path.append('../../../../')
 from config.lib import *
 from tools.pyelf.lmanext import *
 
-src = [Glob('*.[cS]') + Glob('src/*.c') + Glob('src/arch/arm/*.c')]
+src = [Glob('*.[c]') + Glob('test_exec.S') + Glob('src/*.c') + Glob('src/arch/arm/*.c')]
 
 asm_string = \
 '''
@@ -33,7 +33,6 @@ lma_lds = Command('include/linker.lds', [previmage, 'include/linker.lds.in'], ge
 env = environment.Clone()
 test_exec_env = environment.Clone()
 
-
 test_exec_env.Append(LIBS = ['posix', 'c-userspace'])
 test_exec_env.Append(LINKFLAGS = ['-T' + "test0/include/test_exec_linker.lds", '-u_start'])
 test_exec_env.Append(CPPFLAGS = ' -D__USERSPACE__')
@@ -46,11 +45,41 @@ test_exec_asm = Command('test_exec.S', test_exec, generate_incbin_asm)
 env.Append(LIBS = ['posix', 'c-userspace'])
 env.Append(LINKFLAGS = ['-T' + lma_lds[0].path, '-u_start'])
 env.Append(CPPFLAGS = ' -D__USERSPACE__')
+env.Replace(PROGSUFFIX = '')
 objs = env.Object(src + test_exec_asm)
-test0 = env.Program('test0.elf', objs)
+test0 = env.Program('test0', objs)
+
+
+elf_wrap_string = \
+'''
+.align 4
+.section .data
+.incbin "%s"
+'''
+
+def elf_wrap_asm(target, source, env):
+    with open(target[0].path, 'w+') as asm_out:
+        asm_out.write(elf_wrap_string % source[0].path)
+
+def elf_wrap_lds(target, source, env):
+    with open(source[1].path, 'r') as lds_in:
+        with open(target[0].path, 'w+') as lds_out:
+            linker_script = lds_in.read()
+            lds_out.write(linker_script % next_available_lma(source[0].path))
+
+# This further wraps the test0 elf image in another elf. Required.
+elf_wrap_env = environment.Clone()
+elf_wrapped_asm = Command('test0_elf_wrapped.S', test0, elf_wrap_asm)
+elf_wrapped_lds = Command('include/elf_wrapper.lds', [previmage, 'include/elf_wrapper.lds.in'], elf_wrap_lds)
+elf_wrap_env.Append(LINKFLAGS = '-T' + elf_wrapped_lds[0].path)
+elf_wrap_objs = elf_wrap_env.Object(elf_wrapped_asm)
+test0_elf_elf = elf_wrap_env.Program('test0_elf.elf', elf_wrap_objs)
+
 Depends(test0, objs)
 Depends(test0, lma_lds)
 Depends(lma_lds, previmage)
-env.Depends(test0, test_exec)
-
-Return('test0')
+Depends(test0, test_exec)
+Depends(test0_elf_elf, elf_wrap_objs)
+Depends(test0_elf_elf, test0)
+Depends(test0_elf_elf, elf_wrapped_lds)
+Return('test0_elf_elf')

conts/posix/test0/include/elf_wrapper.lds.in

@@ -0,0 +1,6 @@
+SECTIONS
+{
+	. = %s;
+	.data : { *(.data) }
+	_end = .;
+}

loader/libs/elf/src/elf.c

@@ -376,9 +376,7 @@ elf_loadFile(void *elfFile, bool phys)
 		pheader_type = elf_getProgramHeaderType(elfFile, i);
 	//	printf("Elf program header type: %p\n", pheader_type);
 
-/* Enable this one
 		printf("Copying to range from 0x%x to 0x%x of size: 0x%x\n", (unsigned int)dest, (unsigned int)dest + (unsigned int)len, (unsigned int)len);
- */
 		memcpy((void*) (uintptr_t) dest, (void*) (uintptr_t) src, len);
 		dest += len;
 		clrsize = elf_getProgramHeaderMemorySize(elfFile, i) - len;
@@ -387,7 +385,7 @@ elf_loadFile(void *elfFile, bool phys)
 //		printf("Memory cleared.\n");
 	}
 // And this one
-//	printf("\n");
+	printf("\n");
 
 	return true;
 }