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

/*  slibtool: a skinny libtool implementation, written in C        */

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

/*  Released under the Standard MIT License; see COPYING.SLIBTOOL. */

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

#include <stdio.h>

#include <string.h>

#include <stdbool.h>

#include <unistd.h>

#include "slibtool_symlink_impl.h"

#define SLBT_DEV_NULL_FLAGS	(SLBT_DRIVER_ALL_STATIC \

				| SLBT_DRIVER_DISABLE_SHARED)

int slbt_create_symlink(

	const struct slbt_driver_ctx *	dctx,

	struct slbt_exec_ctx *		ectx,

	const char *			target,

	const char *			lnkname,

	bool				flawrapper)

{

	char **		oargv;

	const char *	slash;

	char *		ln[5];

	char *		dotdot;

	char		tmplnk [PATH_MAX];

	char		lnkarg [PATH_MAX];

	char		atarget[PATH_MAX];

	/* atarget */

	if ((dctx->cctx->drvflags & SLBT_DEV_NULL_FLAGS)

			&& !strcmp(target,"/dev/null"))

		slash = target;

	else if ((slash = strrchr(target,'/')))

		slash++;

	else

		slash = target;

	dotdot = flawrapper ? "../" : "";

	if ((size_t)snprintf(atarget,sizeof(atarget),"%s%s",

			dotdot,slash) >= sizeof(atarget))

		return -1;

	/* tmplnk */

	if ((size_t)snprintf(tmplnk,sizeof(tmplnk),"%s.symlink.tmp",

			lnkname) >= sizeof(tmplnk))

		return -1;

	/* lnkarg */

	strcpy(lnkarg,lnkname);

	/* ln argv (fake) */

	ln[0] = "ln";

	ln[1] = "-s";

	ln[2] = atarget;

	ln[3] = lnkarg;

	ln[4] = 0;

	oargv      = ectx->argv;

	ectx->argv = ln;

	/* step output */

	if (!(dctx->cctx->drvflags & SLBT_DRIVER_SILENT)) {

		if (dctx->cctx->mode == SLBT_MODE_LINK) {

			if (slbt_output_link(dctx,ectx)) {

				ectx->argv = oargv;

				return -1;

			}

		} else {

			if (slbt_output_install(dctx,ectx)) {

				ectx->argv = oargv;

				return -1;

			}

		}

	}

	/* restore execution context */

	ectx->argv = oargv;

	/* create symlink */

	if (symlink(atarget,tmplnk))

		return -1;

	return rename(tmplnk,lnkname);

}