/*

* smatch/check_propagate.c

*

* Copyright (C) 2010 Dan Carpenter.

*

* Licensed under the Open Software License version 1.1

*

*/

/*

* People should just return the error codes they received

* instead of making up there own dumb error codes all the time.

*/

#include "smatch.h"

static int my_id;

static struct expression *last_return;

static struct expression *last_func;

static char *get_fn_name(struct expression *expr)

{

if (expr->type != EXPR_CALL)

return NULL;

if (expr->fn->type != EXPR_SYMBOL)

return NULL;

return expr_to_var(expr->fn);

}

static void match_call_assignment(struct expression *expr)

{

if (get_macro_name(expr->left->pos))

return;

last_return = expr->left;

last_func = expr->right;

}

static void match_unset(struct expression *expr)

{

last_return = NULL;

}

static void match_return(struct expression *ret_value)

{

sval_t rval;

sval_t lret;

char *name;

if (!get_value(ret_value, &rval) || rval.value >= 0)

return;

if (get_implied_value(last_return, &lret))

return;

if (!get_implied_max(last_return, &lret) || lret.value >= 0)

return;

if (get_implied_min(last_return, &lret) && !sval_is_min(lret))

return;

name = expr_to_var(last_return);

sm_msg("info: why not propagate '%s' from %s() instead of %s?",

name, get_fn_name(last_func), sval_to_str(rval));

free_string(name);

}

void check_propagate(int id)

{

if (option_project != PROJ_KERNEL)

return;

my_id = id;

add_hook(&match_unset, ASSIGNMENT_HOOK);

add_hook(&match_call_assignment, CALL_ASSIGNMENT_HOOK);

add_hook(&match_return, RETURN_HOOK);

}