ubuntu-buildroot/output/build/host-gawk-5.2.0/ext.c

270 lines
6.9 KiB
C

/*
* ext.c - Builtin function that links external gawk functions and related
* utilities.
*
* Christos Zoulas, Thu Jun 29 17:40:41 EDT 1995
* Arnold Robbins, update for 3.1, Mon Nov 23 12:53:39 EST 1998
*/
/*
* Copyright (C) 1995 - 2001, 2003-2014, 2016-2020, 2022,
* the Free Software Foundation, Inc.
*
* This file is part of GAWK, the GNU implementation of the
* AWK Programming Language.
*
* GAWK is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* GAWK is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
#include "awk.h"
extern SRCFILE *srcfiles;
#ifdef DYNAMIC
#include <dlfcn.h>
#define INIT_FUNC "dl_load"
/* load_ext --- load an external library */
void
load_ext(const char *lib_name)
{
int (*install_func)(const gawk_api_t *const, awk_ext_id_t);
void *dl;
int flags = RTLD_LAZY;
int *gpl_compat;
if (do_sandbox)
fatal(_("extensions are not allowed in sandbox mode"));
if (do_traditional || do_posix)
fatal(_("-l / @load are gawk extensions"));
if (lib_name == NULL)
fatal(_("load_ext: received NULL lib_name"));
if ((dl = dlopen(lib_name, flags)) == NULL)
fatal(_("load_ext: cannot open library `%s': %s"), lib_name,
dlerror());
/* Per the GNU Coding standards */
gpl_compat = (int *) dlsym(dl, "plugin_is_GPL_compatible");
if (gpl_compat == NULL)
fatal(_("load_ext: library `%s': does not define `plugin_is_GPL_compatible': %s"),
lib_name, dlerror());
install_func = (int (*)(const gawk_api_t *const, awk_ext_id_t))
dlsym(dl, INIT_FUNC);
if (install_func == NULL)
fatal(_("load_ext: library `%s': cannot call function `%s': %s"),
lib_name, INIT_FUNC, dlerror());
if (install_func(& api_impl, NULL /* ext_id */) == 0)
warning(_("load_ext: library `%s' initialization routine `%s' failed"),
lib_name, INIT_FUNC);
}
/* make_builtin --- register name to be called as func with a builtin body */
awk_bool_t
make_builtin(const char *name_space, const awk_ext_func_t *funcinfo)
{
NODE *symbol, *f;
INSTRUCTION *b;
const char *name = funcinfo->name;
int count = funcinfo->max_expected_args;
const char *install_name;
if (name == NULL || *name == '\0')
fatal(_("make_builtin: missing function name"));
if (! is_valid_identifier(name))
return awk_false;
assert(name_space != NULL);
if (name_space[0] == '\0' || strcmp(name_space, awk_namespace) == 0) {
if (check_special(name) >= 0)
fatal(_("make_builtin: cannot use gawk built-in `%s' as function name"), name);
f = lookup(name);
install_name = estrdup(name, strlen(name));
} else {
if (! is_valid_identifier(name_space))
return awk_false;
if (check_special(name_space) >= 0)
fatal(_("make_builtin: cannot use gawk built-in `%s' as namespace name"), name_space);
if (check_special(name) >= 0)
fatal(_("make_builtin: cannot use gawk built-in `%s' as function name"), name);
size_t len = strlen(name_space) + 2 + strlen(name) + 1;
char *buf;
emalloc(buf, char *, len, "make_builtin");
sprintf(buf, "%s::%s", name_space, name);
install_name = buf;
f = lookup(install_name);
}
if (f != NULL) {
// found it, but it shouldn't be there if we want to install this function
if (f->type == Node_func) {
/* user-defined function */
fatal(_("make_builtin: cannot redefine function `%s'"), name);
} else if (f->type == Node_ext_func) {
/* multiple extension() calls etc. */
if (do_lint)
lintwarn(_("make_builtin: function `%s' already defined"), name);
free((void *) install_name);
return awk_false;
} else
/* variable name etc. */
fatal(_("make_builtin: function name `%s' previously defined"), name);
}
if (count < 0)
fatal(_("make_builtin: negative argument count for function `%s'"),
name);
b = bcalloc(Op_symbol, 1, 0);
b->extfunc = funcinfo->function;
b->c_function = (awk_ext_func_t *) funcinfo;
/* NB: extension sub must return something */
symbol = install_symbol(install_name, Node_ext_func);
symbol->code_ptr = b;
track_ext_func(name);
return awk_true;
}
/* get_argument --- get the i'th argument of a dynamically linked function */
NODE *
get_argument(int i)
{
NODE *t;
int arg_count;
INSTRUCTION *pc;
pc = TOP()->code_ptr; /* Op_ext_builtin instruction */
arg_count = pc->expr_count; /* # of arguments supplied */
if (i < 0 || i >= arg_count)
return NULL;
t = PEEK(arg_count - i);
if (t->type == Node_param_list)
t = GET_PARAM(t->param_cnt);
if (t->type == Node_array_ref) {
if (t->orig_array->type == Node_var) {
/* already a scalar, can no longer use it as array */
t->type = Node_var;
t->var_value = Nnull_string;
return t;
}
return t->orig_array; /* Node_var_new or Node_var_array */
}
if (t->type == Node_var) /* See Case Node_var in setup_frame(), eval.c */
return Nnull_string;
/* Node_var_new, Node_var_array or Node_val */
return t;
}
/*
* get_actual_argument --- get the i'th scalar or array argument of a
* dynamically linked function.
*/
NODE *
get_actual_argument(NODE *t, int i, bool want_array)
{
char *fname;
INSTRUCTION *pc;
pc = TOP()->code_ptr; /* Op_ext_builtin instruction */
fname = (pc + 1)->func_name;
if (t->type == Node_var_new || t->type == Node_elem_new) {
if (want_array)
return force_array(t, false);
else {
t->type = Node_var;
t->var_value = dupnode(Nnull_string);
return t->var_value;
}
}
if (want_array) {
if (t->type != Node_var_array)
fatal(_("function `%s': argument #%d: attempt to use scalar as an array"),
fname, i + 1);
} else {
if (t->type != Node_val)
fatal(_("function `%s': argument #%d: attempt to use array as a scalar"),
fname, i + 1);
}
assert(t->type == Node_var_array || t->type == Node_val);
return t;
}
#else
/* load_ext --- dummy version if extensions not available */
void
load_ext(const char *lib_name)
{
fatal(_("dynamic loading of libraries is not supported"));
}
#endif
/* close_extensions --- execute extension cleanup routines */
void
close_extensions()
{
SRCFILE *s;
if (srcfiles == NULL)
return;
for (s = srcfiles->next; s != srcfiles; s = s->next)
if (s->stype == SRC_EXTLIB && s->fini_func)
(*s->fini_func)();
}
/* is_valid_identifier --- return true if name is a valid simple identifier */
bool
is_valid_identifier(const char *name)
{
const char *sp = name;
int c;
if (! is_letter(*sp))
return false;
for (sp++; (c = *sp++) != '\0';) {
if (! is_identchar(c))
return false;
}
return true;
}