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

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

/*  Copyright (C) 2015--2021  Z. Gilboa                   */

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

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

#include <stdio.h>

#include <stdint.h>

#include <stddef.h>

#include <stdlib.h>

#include <string.h>

#include <unistd.h>

#include <errno.h>

#include <sys/mman.h>

#include <cparser/driver/driver.h>

#include <cparser/driver/c_driver.h>

#include <apimagic/apimagic.h>

#include "apimagic_driver_impl.h"

#include "apimagic_errinfo_impl.h"

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

{

	if (ctx) {

		if (ctx->entities)

			amgc_free_unit_entities(ctx->entities);

		free(ctx);

	}

	return ret;

}

static int amgc_stdin_to_tmp(const struct amgc_driver_ctx * dctx)

{

	struct amgc_driver_ctx_impl *	ictx;

	uintptr_t			addr;

	int				fdtmp;

	ssize_t ret;

	ssize_t cnt;

	char *	ch;

	char	buf[4096];

	char	template[] = "/tmp/amgc_stdin_to_tmp_XXXXXX";

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

	ictx = (struct amgc_driver_ctx_impl *)addr;

	if (ictx->fdtmpin >= 0)

		return dup(ictx->fdtmpin);

	if ((fdtmp = mkstemp(template)) < 0)

		return -1;

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

		close(fdtmp);

		return -1;

	}

	for (;;) {

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

		while ((ret < 0) && (errno == EINTR))

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

		if (ret < 0) {

			close(fdtmp);

			return -1;

		} else if (ret == 0) {

			return fdtmp;

		} else {

			ch  = buf;

			cnt = ret;

			ret = 0;

			for (; cnt; ) {

				ret = write(fdtmp,ch,cnt);

				while ((ret < 0) && (errno == EINTR))

					ret = write(fdtmp,ch,cnt);

				if (ret < 0) {

					close(fdtmp);

					return -1;

				}

				ch  += ret;

				cnt -= ret;

			}

		}

	}

}

static bool amgc_cparser_no_op(

	compilation_env_t *	env,

	compilation_unit_t *	unit)

{

	(void)env;

	(void)unit;

	return true;

}

static void amgc_init_cparser_unit(void)

{

	set_default_handlers();

	/* parse only */

	set_unit_handler(COMPILATION_UNIT_AST,

			build_firm_ir,true);

	/* assign no-op handler */

	set_unit_handler(COMPILATION_UNIT_PREPROCESSED_ASSEMBLER,

			amgc_cparser_no_op,true);

	set_unit_handler(COMPILATION_UNIT_OBJECT,

			amgc_cparser_no_op,true);

}

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;

	int				fd;

	amgc_init_cparser_unit();

	if (!dctx)

		return AMGC_CUSTOM_ERROR(

			dctx,AMGC_ERR_NULL_CONTEXT);

	else if (!(ctx = calloc(1,sizeof(*ctx))))

		return AMGC_SYSTEM_ERROR(dctx);

	amgc_driver_set_ectx(

		dctx,0,path);

	if (strcmp(path,"-"))

		fd = -1;

	else if ((fd = amgc_stdin_to_tmp(dctx)) < 0)

		return amgc_free_unit_ctx_impl(

			ctx,AMGC_SYSTEM_ERROR(dctx));

	else if (lseek(fd,0,SEEK_SET < 0))

		return amgc_free_unit_ctx_impl(

			ctx,AMGC_NESTED_ERROR(dctx));

	else if (!(ctx->ccunit.input = fdopen(fd,"r")))

		return amgc_free_unit_ctx_impl(

			ctx,AMGC_FILE_ERROR(dctx));

	/* compilation unit */

	ctx->ccunit.name		= path;

	ctx->ccunit.original_name	= path;

	ctx->ccunit.type		= COMPILATION_UNIT_C;

	ctx->ccunit.standard		= dctx->cctx->std;

	/* parse, generate ast, generate ir */

	if ((process_unit(ctx->cctx.ccenv,&ctx->ccunit)) == false) {

		if (ctx->ccunit.input)

			fclose(ctx->ccunit.input);

		return amgc_free_unit_ctx_impl(

			ctx,AMGC_CUSTOM_ERROR(dctx,AMGC_ERR_FLOW_ERROR));

	}

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

		sizeof(ctx->cctx));

	ctx->dctx	    = dctx;

	ctx->path	    = path;

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

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

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

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

	if (amgc_get_unit_entities(&ctx->uctx,&ctx->meta,&ctx->entities))

		return amgc_free_unit_ctx_impl(

			ctx,AMGC_CUSTOM_ERROR(dctx,AMGC_ERR_FLOW_ERROR));

	ctx->uctx.entities  = ctx->entities;

	*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);

	}

}