now, the system call "execve" sets also the environment

kernel/tasks.c

@@ -377,25 +377,43 @@ static int load_task(load_args_t* largs)
 	}
 
 	// push strings on the stack
-	offset = DEFAULT_STACK_SIZE-MAX_ARGS-8;
+	offset = DEFAULT_STACK_SIZE-8;
+	memset((void*) (stack+offset), 0, 4);
+	offset -= MAX_ARGS;
 	memcpy((void*) (stack+offset), largs->buffer, MAX_ARGS);
 	idx = offset;
 
 	// push argv on the stack
 	offset -= largs->argc * sizeof(char*);
-	i = 0;
-	while(i<largs->argc) {
+	for(i=0; i<largs->argc; i++) {
 		((char**) (stack+offset))[i] = (char*) (stack+idx);
-		i++;
 		
-		while((i<largs->argc) && ((char*) stack)[idx] != '\0')
+		while(((char*) stack)[idx] != '\0')
 			idx++;
 		idx++;
 	}
 
+	// push env on the stack
+	offset -= (largs->envc+1) * sizeof(char*);
+	for(i=0; i<largs->envc; i++) {
+		((char**) (stack+offset))[i] = (char*) (stack+idx);
+
+		while(((char*) stack)[idx] != '\0')
+			idx++;
+		idx++;
+	}
+	((char**) (stack+offset))[largs->envc] = NULL;
+
+	// push pointer to env
+	offset -= sizeof(char**);
+	if (!(largs->envc))
+		*((char***) (stack+offset)) = NULL;
+	else
+		*((char***) (stack+offset)) = (char**) (stack + offset + sizeof(char**));
+
 	// push pointer to argv
 	offset -= sizeof(char**);
-	*((char***) (stack+offset)) = (char**) (stack + offset + sizeof(char**));
+	*((char***) (stack+offset)) = (char**) (stack + offset + 2*sizeof(char**) + (largs->envc+1) * sizeof(char*));
 
 	// push argc on the stack
 	offset -= sizeof(int);
@@ -466,12 +484,13 @@ int sys_execve(const char* fname, char** argv, char** env)
 	load_args_t* load_args = NULL;
 	char *dest, *src;
 	int ret, argc = 0;
+	int envc = 0;
 
 	node = findnode_fs((char*) fname);
 	if (!node || !(node->type == FS_FILE))
 		return -EINVAL;
 
-	// determine buffer size of argv
+	// determine total buffer size of argv and env
 	if (argv) {
 		while (argv[argc]) {
 			buffer_size += (strlen(argv[argc]) + 1);
@@ -479,6 +498,13 @@ int sys_execve(const char* fname, char** argv, char** env)
 		}
 	}
 
+	if (env) {
+		while (env[envc]) {
+			buffer_size += (strlen(env[envc]) + 1);
+			envc++;
+		}
+	}
+
 	if (argc <= 0)
 		return -EINVAL;
 	if (buffer_size >= MAX_ARGS)
@@ -490,12 +516,16 @@ int sys_execve(const char* fname, char** argv, char** env)
 
 	load_args->node = node;
 	load_args->argc = argc;
-	load_args->envc = 0;
+	load_args->envc = envc;
 	dest = load_args->buffer;
 	for (i=0; i<argc; i++) {
 		src = argv[i];
 		while ((*dest++ = *src++) != 0);
 	}
+	for (i=0; i<envc; i++) {
+		src = env[i];
+		while ((*dest++ = *src++) != 0);
+	}
 
 	spinlock_lock(&(per_core(current_task)->vma_lock));
 

newlib/examples/hello.c

@@ -28,10 +28,12 @@ extern int errno;
 int main(int argc, char** argv)
 {
 	int i;
-	char str[] = "Hello World!!!\n";
+	const char str[] = "Hello World!!!\n";
 
+	for(i=0; environ[i]; i++) 
+		printf("environ[%d] = %s\n", i, environ[i]);
 	for(i=0; i<argc; i++)
-		printf("argv[%i] = %s\n", i, argv[i]);
+		printf("argv[%d] = %s\n", i, argv[i]);
 
 	write(1, str, strlen(str));
 

newlib/examples/tests.c

@@ -29,20 +29,20 @@ extern int errno;
 
 int main(int argc, char** argv)
 {
-	int i, status = 0;
+	int status = 0;
 	pid_t pid;
 
 	printf("Create child process...\n");
 
-	for(i=0; i<argc; i++)
-		printf("argv[%i] = %s\n", i, argv[i]);
-
 	pid = fork();
 	if (pid == 0) { // child
-		char* args[] = {"/bin/hello", "one", "two", "three", NULL};
+		char* newargs[] = {"/bin/hello", "one", "two", "three", NULL};
+		char* newenv[] = {"USER=root", "PATH=/bin:/sbin:/usr/bin", "PWD=/", "TEMP=/tmp", NULL};
 
 		printf("Hello from child process!\n");
-		execve("/bin/hello", args, environ);
+		execve("/bin/hello", newargs, newenv);
+
+		return errno;
 	} else {
 		printf("Hello from parent process! pid = %u\n", pid);
 		wait(&status);

newlib/src/libgloss/metalsvm/crt0.asm

@@ -20,6 +20,8 @@
 SECTION .text
 global _start
 extern main
+extern environ
+extern __env
 extern __do_global_dtors
 extern __do_global_ctors
 extern hardware_init_hook
@@ -46,6 +48,17 @@ L2:
    ; call init function
    call __do_global_ctors
 
+   ; set default environment
+   mov eax, environ
+   mov edx, [esp+8]
+   cmp edx, 0
+   je L3
+   mov dword [eax], edx
+   jmp L4
+L3:
+   mov dword [eax], __env
+L4:
+
    ; arguments are already on the stack
    ; call the user's function
    call main

newlib/src/libgloss/metalsvm/environ.c

@@ -18,5 +18,4 @@
  */
 
 /* default environment */
-char *__env[] = { "USER=root", "PATH=/bin:/sbin:/usr/bin", "PWD=/", (char *) 0 };
-char **environ = __env; 
+char* __env[] = {"USER=root", "PATH=/bin:/sbin:/usr/bin", "PWD=/", (char*) 0};