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

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

/*  Copyright (C) 2016--2021  SysDeer Technologies, LLC            */

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

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

#include <stdarg.h>

#include <stdlib.h>

#include <stdio.h>

#include <string.h>

#include <fcntl.h>

#include <errno.h>

#include <sys/stat.h>

#include <slibtool/slibtool.h>

#include "slibtool_driver_impl.h"

#include "slibtool_errinfo_impl.h"

#include "slibtool_linkcmd_impl.h"

#include "slibtool_mapfile_impl.h"

#include "slibtool_metafile_impl.h"

#include "slibtool_snprintf_impl.h"

#include "slibtool_symlink_impl.h"

#include "slibtool_readlink_impl.h"

static int slbt_linkcmd_exit(

	struct slbt_deps_meta *	depsmeta,

	int			ret)

{

	if (depsmeta->altv)

		free(depsmeta->altv);

	if (depsmeta->args)

		free(depsmeta->args);

	return ret;

}

static int slbt_emit_fdwrap_amend_dl_path(

	const struct slbt_driver_ctx *	dctx,

	struct slbt_exec_ctx *		ectx,

	struct slbt_deps_meta * 	depsmeta,

	const char *			fmt,

					...)

{

	va_list		ap;

	char *		buf;

	int		cnt;

	char		dlpathbuf[2048];

	int		fdwrap;

	const char *	fdwrap_fmt;

	int		size;

	va_start(ap,fmt);

	size = sizeof(dlpathbuf);

	buf  = ((cnt = vsnprintf(dlpathbuf,size,fmt,ap)) < size)

		? dlpathbuf : malloc((size = cnt + 1));

	va_end(ap);

	if (buf == dlpathbuf) {

		(void)0;

	} else if (buf) {

		va_start(ap,fmt);

		vsprintf(buf,fmt,ap);

		va_end(ap);

	} else {

		return slbt_linkcmd_exit(

			depsmeta,

			SLBT_SYSTEM_ERROR(dctx,0));

	}

	if ((fdwrap = slbt_exec_get_fdwrapper(ectx)) >= 0) {

		if (buf[0] == '/') {

			fdwrap_fmt =

				"DL_PATH=\"${DL_PATH}${COLON}%s\"\n"

				"COLON=':'\n\n";

		} else {

			fdwrap_fmt =

				"DL_PATH=\"${DL_PATH}${COLON}${DL_PATH_FIXUP}%s\"\n"

				"COLON=':'\n\n";

		}

		if (slbt_dprintf(fdwrap,fdwrap_fmt,buf) < 0) {

			return slbt_linkcmd_exit(

				depsmeta,

				SLBT_SYSTEM_ERROR(dctx,0));

		}

	}

	return 0;

}

bool slbt_adjust_object_argument(

	char *		arg,

	bool		fpic,

	bool		fany,

	int		fdcwd)

{

	char *	slash;

	char *	dot;

	char	base[PATH_MAX];

	if (*arg == '-')

		return false;

	/* object argument: foo.lo or foo.o */

	if (!(dot = strrchr(arg,'.')))

		return false;

	if ((dot[1]=='l') && (dot[2]=='o') && !dot[3]) {

		dot[1] = 'o';

		dot[2] = 0;

	} else if ((dot[1]=='o') && !dot[2]) {

		(void)0;

	} else {

		return false;

	}

	/* foo.o requested and is present? */

	if (!fpic && !faccessat(fdcwd,arg,0,0))

		return true;

	/* .libs/foo.o */

	if ((slash = strrchr(arg,'/')))

		slash++;

	else

		slash = arg;

	if (slbt_snprintf(base,sizeof(base),

			"%s",slash) < 0)

		return false;

	sprintf(slash,".libs/%s",base);

	if (!faccessat(fdcwd,arg,0,0))

		return true;

	/* foo.o requested and neither is present? */

	if (!fpic) {

		strcpy(slash,base);

		return true;

	}

	/* .libs/foo.o explicitly requested and is not present? */

	if (!fany)

		return true;

	/* use foo.o in place of .libs/foo.o */

	strcpy(slash,base);

	if (faccessat(fdcwd,arg,0,0))

		sprintf(slash,".libs/%s",base);

	return true;

}

bool slbt_adjust_wrapper_argument(

	char *		arg,

	bool		fpic)

{

	char *	slash;

	char *	dot;

	char	base[PATH_MAX];

	if (*arg == '-')

		return false;

	if (!(dot = strrchr(arg,'.')))

		return false;

	if (strcmp(dot,".la"))

		return false;

	if (fpic) {

		if ((slash = strrchr(arg,'/')))

			slash++;

		else

			slash = arg;

		if (slbt_snprintf(base,sizeof(base),

				"%s",slash) < 0)

			return false;

		sprintf(slash,".libs/%s",base);

		dot = strrchr(arg,'.');

	}

	strcpy(dot,".a");

	return true;

}

int slbt_adjust_linker_argument(

	const struct slbt_driver_ctx *	dctx,

	char *				arg,

	char **				xarg,

	bool				fpic,

	const char *			dsosuffix,

	const char *			arsuffix,

	struct slbt_deps_meta * 	depsmeta)

{

	int	fdcwd;

	int	fdlib;

	char *	slash;

	char *	dot;

	char	base[PATH_MAX];

	if (*arg == '-')

		return 0;

	if (!(dot = strrchr(arg,'.')))

		return 0;

	if (!(strcmp(dot,arsuffix))) {

		*xarg = arg;

		return slbt_get_deps_meta(dctx,arg,1,depsmeta);

	}

	if (!(strcmp(dot,dsosuffix)))

		return slbt_get_deps_meta(dctx,arg,1,depsmeta);

	if (strcmp(dot,".la"))

		return 0;

	if (fpic) {

		if ((slash = strrchr(arg,'/')))

			slash++;

		else

			slash = arg;

		if (slbt_snprintf(base,sizeof(base),

				"%s",slash) < 0)

			return 0;

		sprintf(slash,".libs/%s",base);

		dot = strrchr(arg,'.');

	}

	/* fdcwd */

	fdcwd = slbt_driver_fdcwd(dctx);

	/* shared library dependency? */

	if (fpic) {

		sprintf(dot,"%s",dsosuffix);

		if (slbt_symlink_is_a_placeholder(fdcwd,arg))

			sprintf(dot,"%s",arsuffix);

		else if ((fdlib = openat(fdcwd,arg,O_RDONLY)) >= 0)

			close(fdlib);

		else

			sprintf(dot,"%s",arsuffix);

		return slbt_get_deps_meta(dctx,arg,0,depsmeta);

	}

	/* input archive */

	sprintf(dot,"%s",arsuffix);

	return slbt_get_deps_meta(dctx,arg,0,depsmeta);

}

int slbt_exec_link_adjust_argument_vector(

	const struct slbt_driver_ctx *	dctx,

	struct slbt_exec_ctx *		ectx,

	struct slbt_deps_meta *		depsmeta,

	const char *			cwd,

	bool				flibrary)

{

	int			fd;

	int			fdcwd;

	char ** 		carg;

	char ** 		aarg;

	char *			ldir;

	char *			slash;

	char *			mark;

	char *			darg;

	char *			dot;

	char *			base;

	char *			dpath;

	int			argc;

	char			arg[PATH_MAX];

	char			lib[PATH_MAX];

	char			depdir  [PATH_MAX];

	char			rpathdir[PATH_MAX];

	char			rpathlnk[PATH_MAX];

	struct stat		st;

	size_t			size;

	size_t			dlen;

	struct slbt_map_info *	mapinfo;

	bool			fwholearchive = false;

	int			ret;

	for (argc=0,carg=ectx->cargv; *carg; carg++)

		argc++;

	if (!(depsmeta->args = calloc(1,depsmeta->infolen)))

		return SLBT_SYSTEM_ERROR(dctx,0);

	argc *= 3;

	argc += depsmeta->depscnt;

	if (!(depsmeta->altv = calloc(argc,sizeof(char *))))

		return slbt_linkcmd_exit(

			depsmeta,

			SLBT_SYSTEM_ERROR(dctx,0));

	fdcwd = slbt_driver_fdcwd(dctx);

	carg = ectx->cargv;

	aarg = depsmeta->altv;

	darg = depsmeta->args;

	size = depsmeta->infolen;

	for (; *carg; ) {

		dpath = 0;

		if (!strcmp(*carg,"-Wl,--whole-archive"))

			fwholearchive = true;

		else if (!strcmp(*carg,"-Wl,--no-whole-archive"))

			fwholearchive = false;

		/* output annotation */

		if (carg == ectx->lout[0]) {

			ectx->mout[0] = &aarg[0];

			ectx->mout[1] = &aarg[1];

		}

		/* argument translation */

		mark = *carg;

		if ((mark[0] == '-') && (mark[1] == 'L')) {

			if (mark[2]) {

				ldir = &mark[2];

			} else {

				*aarg++ = *carg++;

				ldir    = *carg;

			}

			mark = ldir + strlen(ldir);

			if (mark[-1] == '/')

				strcpy(mark,".libs");

			else

				strcpy(mark,"/.libs");

			if ((fd = openat(fdcwd,ldir,O_DIRECTORY,0)) < 0)

				*mark = 0;

			else {

				close(fd);

				if ((ret = slbt_emit_fdwrap_amend_dl_path(

						dctx,ectx,depsmeta,

						"%s",ldir)) < 0)

					return ret;

			}

			*aarg++ = *carg++;

		} else if (**carg == '-') {

			*aarg++ = *carg++;

		} else if (!(dot = strrchr(*carg,'.'))) {

			*aarg++ = *carg++;

		} else if (ectx->xargv[carg - ectx->cargv]) {

			*aarg++ = *carg++;

		} else if (!(strcmp(dot,".a"))) {

			if (flibrary && !fwholearchive)

				*aarg++ = "-Wl,--whole-archive";

			dpath = lib;

			sprintf(lib,"%s.slibtool.deps",*carg);

			*aarg++ = *carg++;

			if (flibrary && !fwholearchive)

				*aarg++ = "-Wl,--no-whole-archive";

		} else if (strcmp(dot,dctx->cctx->settings.dsosuffix)) {

			*aarg++ = *carg++;

		} else if (carg == ectx->lout[1]) {

			/* ^^^hoppla^^^ */

			*aarg++ = *carg++;

		} else {

			/* -rpath */

			sprintf(rpathlnk,"%s.slibtool.rpath",*carg);

			if (!fstatat(fdcwd,rpathlnk,&st,AT_SYMLINK_NOFOLLOW)) {

				if (slbt_readlinkat(

						fdcwd,

						rpathlnk,

						rpathdir,

						sizeof(rpathdir)))

					return slbt_linkcmd_exit(

						depsmeta,

						SLBT_SYSTEM_ERROR(dctx,rpathlnk));

				sprintf(darg,"-Wl,%s",rpathdir);

				*aarg++ = "-Wl,-rpath";

				*aarg++ = darg;

				darg   += strlen(darg);

				darg++;

			}

			dpath = lib;

			sprintf(lib,"%s.slibtool.deps",*carg);

			/* account for {'-','L','-','l'} */

			if (slbt_snprintf(arg,

					sizeof(arg) - 4,

					"%s",*carg) < 0)

				return slbt_linkcmd_exit(

					depsmeta,

					SLBT_BUFFER_ERROR(dctx));

			if ((slash = strrchr(arg,'/'))) {

				sprintf(*carg,"-L%s",arg);

				mark   = strrchr(*carg,'/');

				*mark  = 0;

				*slash = 0;

				if ((ret = slbt_emit_fdwrap_amend_dl_path(

						dctx,ectx,depsmeta,

						"%s%s%s",

						((arg[0] == '/') ? "" : cwd),

						((arg[0] == '/') ? "" : "/"),

						arg)) < 0) {

					return ret;

				}

				dlen = strlen(dctx->cctx->settings.dsoprefix);

				/* -module? (todo: non-portable usage, display warning) */

				if (strncmp(++slash,dctx->cctx->settings.dsoprefix,dlen)) {

					*--slash = '/';

					strcpy(*carg,arg);

					*aarg++ = *carg++;

				} else {

					*aarg++ = *carg++;

					*aarg++ = ++mark;

					slash += dlen;

					sprintf(mark,"-l%s",slash);

					dot  = strrchr(mark,'.');

					*dot = 0;

				}

			} else {

				*aarg++ = *carg++;

			}

		}

		if (dpath && !fstatat(fdcwd,dpath,&st,0)) {

			if (!(mapinfo = slbt_map_file(

					fdcwd,dpath,

					SLBT_MAP_INPUT)))

				return slbt_linkcmd_exit(

					depsmeta,

					SLBT_SYSTEM_ERROR(dctx,dpath));

			if (!(strncmp(lib,".libs/",6))) {

				*aarg++ = "-L.libs";

				lib[1] = 0;

			} else if ((base = strrchr(lib,'/'))) {

				if (base - lib == 5) {

					if (!(strncmp(&base[-5],".libs/",6)))

						base -= 4;

				} else if (base - lib >= 6) {

					if (!(strncmp(&base[-6],"/.libs/",7)))

						base -= 6;

				}

				*base = 0;

			} else {

				lib[0] = '.';

				lib[1] = 0;

			}

			while (mapinfo->mark < mapinfo->cap) {

				if (slbt_mapped_readline(dctx,mapinfo,darg,size))

					return slbt_linkcmd_exit(

						depsmeta,

						SLBT_NESTED_ERROR(dctx));

				*aarg++   = darg;

				mark      = darg;

				dlen      = strlen(darg);

				size     -= dlen;

				darg     += dlen;

				darg[-1]  = 0;

				/* handle -L... as needed */

				if ((mark[0] == '-')

						&& (mark[1] == 'L')

						&& (mark[2] != '/')) {

					if (strlen(mark) >= sizeof(depdir) - 1)

						return slbt_linkcmd_exit(

							depsmeta,

							SLBT_BUFFER_ERROR(dctx));

					darg = mark;

					strcpy(depdir,&mark[2]);

					sprintf(darg,"-L%s/%s",lib,depdir);

					darg += strlen(darg);

					darg++;

					if ((ret = slbt_emit_fdwrap_amend_dl_path(

							dctx,ectx,depsmeta,

							"%s/%s",lib,depdir)) < 0)

						return ret;

				} else if ((mark[0] == '-') && (mark[1] == 'L')) {

					if ((ret = slbt_emit_fdwrap_amend_dl_path(

							dctx,ectx,depsmeta,

							"%s",&mark[2])) < 0)

						return ret;

				}

			}

		}

	}

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

		*aarg++ = "-Wl,--export-dynamic";

	return 0;

}

int slbt_exec_link_finalize_argument_vector(

	const struct slbt_driver_ctx *	dctx,

	struct slbt_exec_ctx *		ectx)

{

	char *		sargv[1024];

	char **		sargvbuf;

	char **		base;

	char **		parg;

	char **		aarg;

	char **		oarg;

	char **		larg;

	char **		darg;

	char **		earg;

	char **		rarg;

	char **		aargv;

	char **		oargv;

	char **		cap;

	char **		src;

	char **		dst;

	char *		arg;

	char *		dot;

	char *		ccwrap;

	const char *	arsuffix;

	/* vector size */

	base     = ectx->argv;

	arsuffix = dctx->cctx->settings.arsuffix;

	for (parg=base; *parg; parg++)

		(void)0;

	/* buffer */

	if (parg - base < 512) {

		aargv    = &sargv[0];

		oargv    = &sargv[512];

		aarg     = aargv;

		oarg     = oargv;

		sargvbuf = 0;

	} else if (!(sargvbuf = calloc(2*(parg-base+1),sizeof(char *)))) {

		return SLBT_SYSTEM_ERROR(dctx,0);

	} else {

		aargv = &sargvbuf[0];

		oargv = &sargvbuf[parg-base+1];

		aarg  = aargv;

		oarg  = oargv;

	}

	/* (program name) */

	parg = &base[1];

	/* split object args from all other args, record output */

	/* annotation, and remove redundant -l arguments       */

	for (; *parg; ) {

		if (ectx->lout[0] == parg) {

			ectx->lout[0] = &aarg[0];

			ectx->lout[1] = &aarg[1];

		}

		if (ectx->mout[0] == parg) {

			ectx->mout[0] = &aarg[0];

			ectx->mout[1] = &aarg[1];

		}

		arg = *parg;

		dot = strrchr(arg,'.');

		/* object input argument? */

		if (dot && (!strcmp(dot,".o") || !strcmp(dot,".lo"))) {

			*oarg++ = *parg++;

		/* --whole-archive input argument? */

		} else if ((arg[0] == '-')

				&& (arg[1] == 'W')

				&& (arg[2] == 'l')

				&& (arg[3] == ',')

				&& !strcmp(&arg[4],"--whole-archive")

				&& parg[1] && parg[2]

				&& !strcmp(parg[2],"-Wl,--no-whole-archive")

				&& (dot = strrchr(parg[1],'.'))

				&& !strcmp(dot,arsuffix)) {

			*oarg++ = *parg++;

			*oarg++ = *parg++;

			*oarg++ = *parg++;

		/* local archive input argument? */

		} else if (dot && !strcmp(dot,arsuffix)) {

			*oarg++ = *parg++;

		/* -l argument? */

		} else if ((parg[0][0] == '-') && (parg[0][1] == 'l')) {

			/* find the previous occurence of this -l argument */

			for (rarg=0, larg=&aarg[-1]; !rarg && (larg>=aargv); larg--)

				if (!strcmp(*larg,*parg))

					rarg = larg;

			/* first occurence of this specific -l argument? */

			if (!rarg) {

				*aarg++ = *parg++;

			} else {

				larg = rarg;

				/* if all -l arguments following the previous */

				/* occurence had already appeared before the */

				/* previous argument, then the current      */

				/* occurence is redundant.                 */

				for (darg=&larg[1]; rarg && darg

					/* only test -l arguments */

					if ((darg[0][0] == '-') && (darg[0][1] == 'l')) {

						for (rarg=0, earg=aargv; !rarg && earg

							if (!strcmp(*earg,*darg))

								rarg = darg;

					}

				}

				/* final verdict: repeated -l argument? */

				if (rarg) {

					parg++;

				} else {

					*aarg++ = *parg++;

				}

			}

		/* -L argument? */

		} else if ((parg[0][0] == '-') && (parg[0][1] == 'L')) {

			/* find a previous occurence of this -L argument */

			for (rarg=0, larg=aargv; !rarg && (larg

				if (!strcmp(*larg,*parg))

					rarg = larg;

			/* repeated -L argument? */

			if (rarg) {

				parg++;

			} else {

				*aarg++ = *parg++;

			}

		/* placeholder argument? */

		} else if (!strncmp(*parg,"-USLIBTOOL_PLACEHOLDER_",23)) {

			parg++;

		/* all other arguments */

		} else {

			*aarg++ = *parg++;

		}

	}

	/* program name, ccwrap */

	if ((ccwrap = (char *)dctx->cctx->ccwrap)) {

		base[1] = base[0];

		base[0] = ccwrap;

		base++;

	}

	/* join object args */

	src = oargv;

	cap = oarg;

	dst = &base[1];

	for (; src

		*dst++ = *src++;

	/* join all other args */

	src = aargv;

	cap = aarg;

	for (; src

		*dst++ = *src++;

	/* properly null-terminate argv, accounting for redundant -l arguments */