/**********************************************************/

/*  apimagic: cparser-based API normalization utility     */

/*  Copyright (C) 2015--2016  Z. Gilboa                   */

/*  Released under GPLv2 and GPLv3; see COPYING.APIMAGIC. */

/**********************************************************/

#include <stdint.h>

#include <stddef.h>

#include <stdlib.h>

#include <string.h>

#include <unistd.h>

#include <errno.h>

#include <sys/mman.h>

#include <apimagic/apimagic.h>

#include "apimagic_driver_impl.h"

static int amgc_free_unit_ctx_impl(struct amgc_unit_ctx_impl * ctx, int status)

{

	if (ctx) {

		amgc_unmap_input(&ctx->map);

		free(ctx);

	}

	return status;

}

static FILE * amgc_stdin_to_tmp(const struct amgc_driver_ctx * dctx)

{

	struct amgc_driver_ctx_impl *	ictx;

	uintptr_t			addr;

	int				fdtmp;

	FILE *	ftmp;

	char	buf[4096];

	ssize_t	nread;

	int	ret;

	addr = (uintptr_t)dctx - offsetof(struct amgc_driver_ctx_impl,ctx);

	ictx = (struct amgc_driver_ctx_impl *)addr;

	if (ictx->fdtmpin >= 0) {

		if ((fdtmp = dup(ictx->fdtmpin)) < 0)

			return 0;

		if (!(ftmp = fdopen(fdtmp,"r")))

			close(fdtmp);

		return ftmp;

	}

	if (!(ftmp = tmpfile()))

		return 0;

	if ((ictx->fdtmpin = dup(fileno(ftmp))) < 0) {

		fclose(ftmp);

		return 0;

	}

	nread = read(0,buf,sizeof(buf)-1);

	while (nread) {

		if (nread > 0) {

			buf[nread] = '\0';

			ret = fputs(buf,ftmp);

		} else

			ret = (errno == EINTR) ? 0 : -1;

		if (ret < 0) {

			fclose(ftmp);

			return 0;

		}

		nread = read(0,buf,sizeof(buf)-1);

	}

	return ftmp;

}

int amgc_get_unit_ctx(

	const struct amgc_driver_ctx *	dctx,

	const char *			path,

	struct amgc_unit_ctx **		pctx)

{

	struct amgc_unit_ctx_impl *	ctx;

	FILE *				ftmp;

	int				fd;

	if (!dctx || !(ctx = calloc(sizeof(*ctx),1)))

		return -1;

	if (strcmp(path,"-"))

		fd = -1;

	else if (!(ftmp = amgc_stdin_to_tmp(dctx)))

		return amgc_free_unit_ctx_impl(ctx,-1);

	else if ((fd = dup(fileno(ftmp))) < 0)

		return amgc_free_unit_ctx_impl(ctx,-1);

	else

		fclose(ftmp);

	if (amgc_map_input(fd,path,PROT_READ,&ctx->map))

		return amgc_free_unit_ctx_impl(ctx,-1);

	if (fd > 0)

		close(fd);

	memcpy(&ctx->cctx,dctx->cctx,

		sizeof(ctx->cctx));

	ctx->path	= path;

	ctx->uctx.path	= &ctx->path;

	ctx->uctx.map	= &ctx->map;

	ctx->uctx.cctx	= &ctx->cctx;

	*pctx = &ctx->uctx;

	return 0;

}

void amgc_free_unit_ctx(struct amgc_unit_ctx * ctx)

{

	struct amgc_unit_ctx_impl *	ictx;

	uintptr_t			addr;

	if (ctx) {

		addr = (uintptr_t)ctx - offsetof(struct amgc_unit_ctx_impl,uctx);

		ictx = (struct amgc_unit_ctx_impl *)addr;

		amgc_free_unit_ctx_impl(ictx,0);

	}

}