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#include <stdlib.h>
#include <stdio.h>
#include <libfungw/fungw.h>
/* User configuration for this example: change language and script file name */
#define SCLANG fawk
#define SCLANG_STR "fawk"
#define SCRIPT_FN "../00_hello/hello.fawk"
/* Macro wizardy for making the example language-independent */
#define SCLANG_INIT_(LANG) pplg_init_fungw_ ## LANG ()
#define SCLANG_INIT(LANG) SCLANG_INIT_(LANG)
extern int SCLANG_INIT(SCLANG);
/* Handle runtime fungw errors - inform the user */
void async_error(fgw_obj_t *obj, const char *msg)
{
printf("Async error: %s: %s\n", obj->name, msg);
}
/* Script calls C function: wrapper for atoi() */
fgw_error_t fgwc_atoi(fgw_arg_t *res, int argc, fgw_arg_t *argv)
{
FGW_DECL_CTX; /* setup for the FGW macro shorthands, initializes fgw_ctx_t *ctx */
FGW_ARGC_REQ_MATCH(1); /* require exactly one argument */
FGW_ARG_CONV(&argv[1], FGW_STR); /* make sure argv[1] is a string */
/* call the function, prepare the result in res */
res->val.nat_int = atoi(argv[1].val.str);
res->type = FGW_INT;
return FGW_SUCCESS;
}
int main(int argc, char *argv[])
{
fgw_ctx_t ctx;
fgw_obj_t *hobj, *sobj;
fgw_arg_t res;
int rv;
/* Initialize the language engine; in a more advanced setup the .so is
loaded using dlopen() which automates this step; in a static link
setup, like this example, the script lang engine needs to be linked and
initialized manually. */
SCLANG_INIT(SCLANG);
/* initialize a context */
fgw_init(&ctx, "my_context");
ctx.async_error = async_error;
/* create a host object and register our own functions there */
hobj = fgw_obj_reg(&ctx, "host_app");
fgw_func_reg(hobj, "atoi", fgwc_atoi);
/* create objects (load script) */
sobj = fgw_obj_new(&ctx, "hello", SCLANG_STR, SCRIPT_FN, NULL);
if (sobj == NULL) {
fprintf(stderr, "ERROR: failed to load script %s (language %s)\n", SCRIPT_FN, SCLANG_STR);
return 1;
}
/* Call a script function */
printf("\n### Call hello()\n");
rv = fgw_vcall(&ctx, &res, "hello", FGW_INT, (int)12, FGW_STR, "blobbs", 0);
if (rv == 0) {
int cr = fgw_arg_conv(&ctx, &res, FGW_INT); /* convert result to int if it is not an int already */
if (cr == 0)
printf("hello() result=%d\n", res.val.nat_int);
else
printf("hello() result=<conversion failure>\n");
}
else
fprintf(stderr, "ERROR: calling hello() failed\n");
fgw_uninit(&ctx); /* uninit the context; new contexts could still be created */
fgw_atexit(); /* free all memory used by the lib */
return 0;
}
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