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

/*  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 <stdint.h>

#include <string.h>

#include <unistd.h>

#include <stdlib.h>

#include <stdbool.h>

#include <fcntl.h>

#include <spawn.h>

#include <sys/wait.h>

#include <slibtool/slibtool.h>

#include "slibtool_driver_impl.h"

#include "slibtool_errinfo_impl.h"

#include "slibtool_ar_impl.h"

/* annotation strings */

static const char cfgexplicit[] = "command-line argument";

static const char cfghost[]     = "derived from <host>";

static const char cfgtarget[]   = "derived from <target>";

static const char cfgcompiler[] = "derived from <compiler>";

static const char cfgnmachine[] = "native (cached in ccenv/host.mk)";

static const char cfgxmachine[] = "foreign (derived from -dumpmachine)";

static const char cfgnative[]   = "native";

/* elf rpath */

static const char*ldrpath_elf[] = {

	"/lib",

	"/lib/64",

	"/usr/lib",

	"/usr/lib64",

	"/usr/local/lib",

	"/usr/local/lib64",

	0};

/* flavor settings */

#define SLBT_FLAVOR_SETTINGS(flavor,          \

		bfmt,pic,                     \

		arp,ars,dsop,dsos,osds,osdf,  \

		exep,exes,impp,imps,          \

		ldenv)                        \

	static const struct slbt_flavor_settings flavor = {  \

		bfmt,arp,ars,dsop,dsos,osds,osdf,           \

		exep,exes,impp,imps,                       \

		ldenv,pic}

SLBT_FLAVOR_SETTINGS(host_flavor_default,       \

	"elf","-fPIC",                          \

	"lib",".a","lib",".so",".so","",        \

	"","","","",                            \

	"LD_LIBRARY_PATH");

SLBT_FLAVOR_SETTINGS(host_flavor_midipix,       \

	"pe","-fPIC",                           \

	"lib",".a","lib",".so",".so","",        \

	"","","lib",".lib.a",                   \

	"LD_LIBRARY_PATH");

SLBT_FLAVOR_SETTINGS(host_flavor_mingw,         \

	"pe",0,                                 \

	"lib",".a","lib",".dll","",".dll",      \

	"",".exe","lib",".dll.a",               \

	"PATH");

SLBT_FLAVOR_SETTINGS(host_flavor_cygwin,        \

	"pe",0,                                 \

	"lib",".a","lib",".dll","",".dll",      \

	"",".exe","lib",".dll.a",               \

	"PATH");

SLBT_FLAVOR_SETTINGS(host_flavor_darwin,        \

	"macho","-fPIC",                        \

	"lib",".a","lib",".dylib","",".dylib",  \

	"","","","",                            \

	"DYLD_LIBRARY_PATH");

static void slbt_get_host_quad(

	char *	hostbuf,

	char ** hostquad)

{

	char *	mark;

	char *	ch;

	int	i;

	for (i=0, ch=hostbuf, mark=hostbuf; *ch && i<4; ch++) {

		if (*ch == '-') {

			*ch = 0;

			hostquad[i++] = mark;

			mark = &ch[1];

		}

	}

	if (i<4)

		hostquad[i] = mark;

	if (i==3) {

		hostquad[1] = hostquad[2];

		hostquad[2] = hostquad[3];

		hostquad[3] = 0;

	}

}

static void slbt_spawn_ar(char ** argv, int * ecode)

{

	int	estatus;

	pid_t	pid;

	*ecode = 127;

	if ((pid = fork()) < 0) {

		return;

	} else if (pid == 0) {

		execvp(argv[0],argv);

		_exit(errno);

	} else {

		waitpid(pid,&estatus,0);

		if (WIFEXITED(estatus))

			*ecode = WEXITSTATUS(estatus);

	}

}

int slbt_init_host_params(

	const struct slbt_driver_ctx *	dctx,

	const struct slbt_common_ctx *	cctx,

	struct slbt_host_strs *		drvhost,

	struct slbt_host_params *	host,

	struct slbt_host_params *	cfgmeta,

	const char *                    cfgmeta_ar,

	const char *                    cfgmeta_ranlib)

{

	int		fdcwd;

	int		arprobe;

	int		arfd;

	int		ecode;

	size_t		toollen;

	char *		dash;

	char *		base;

	char *		mark;

	const char *	machine;

	bool		ftarget       = false;

	bool		fhost         = false;

	bool		fcompiler     = false;

	bool		fnative       = false;

	bool		fdumpmachine  = false;

	char		buf        [256];

	char		hostbuf    [256];

	char		machinebuf [256];

	char *		hostquad   [4];

	char *		machinequad[4];

	char *		arprobeargv[4];

	char		archivename[] = "/tmp/slibtool.ar.probe.XXXXXXXXXXXXXXXX";

	/* base */

	if ((base = strrchr(cctx->cargv[0],'/')))

		base++;

	else

		base = cctx->cargv[0];

	fdumpmachine  = (cctx->mode == SLBT_MODE_COMPILE)

			|| (cctx->mode == SLBT_MODE_LINK)

			|| (cctx->mode == SLBT_MODE_INFO);

	fdumpmachine &= (!strcmp(base,"xgcc")

			|| !strcmp(base,"xg++"));

	/* support the portbld <--> unknown synonym */

	if (!(drvhost->machine = strdup(SLBT_MACHINE)))

		return -1;

	if ((mark = strstr(drvhost->machine,"-portbld-")))

		memcpy(mark,"-unknown",8);

	/* host */

	if (host->host) {

		cfgmeta->host = cfgexplicit;

		fhost         = true;

	} else if (cctx->target) {

		host->host    = cctx->target;

		cfgmeta->host = cfgtarget;

		ftarget       = true;

	} else if (strrchr(base,'-')) {

		if (!(drvhost->host = strdup(cctx->cargv[0])))

			return -1;

		dash          = strrchr(drvhost->host,'-');

		*dash         = 0;

		host->host    = drvhost->host;

		cfgmeta->host = cfgcompiler;

		fcompiler     = true;

	} else if (!fdumpmachine) {

		host->host    = drvhost->machine;

		cfgmeta->host = cfgnmachine;

	} else if (slbt_dump_machine(cctx->cargv[0],buf,sizeof(buf)) < 0) {

		if (dctx)

			slbt_dprintf(

				slbt_driver_fderr(dctx),

				"%s: could not determine host "

				"via -dumpmachine\n",

				dctx->program);

		return -1;

	} else {

		if (!(drvhost->host = strdup(buf)))

			return -1;

		host->host    = drvhost->host;

		fcompiler     = true;

		fnative       = !strcmp(host->host,drvhost->machine);

		cfgmeta->host = fnative ? cfgnmachine : cfgxmachine;

		if (!fnative) {

			strcpy(hostbuf,host->host);

			strcpy(machinebuf,drvhost->machine);

			slbt_get_host_quad(hostbuf,hostquad);

			slbt_get_host_quad(machinebuf,machinequad);

			if (hostquad[2] && machinequad[2])

				fnative = !strcmp(hostquad[0],machinequad[0])

					&& !strcmp(hostquad[1],machinequad[1])

					&& !strcmp(hostquad[2],machinequad[2]);

		}

	}

	/* flavor */

	if (host->flavor) {

		cfgmeta->flavor = cfgexplicit;

	} else {

		if (fhost) {

			machine         = host->host;

			cfgmeta->flavor = cfghost;

		} else if (ftarget) {

			machine         = cctx->target;

			cfgmeta->flavor = cfgtarget;

		} else if (fcompiler) {

			machine         = drvhost->host;

			cfgmeta->flavor = cfgcompiler;

		} else {

			machine         = drvhost->machine;

			cfgmeta->flavor = cfgnmachine;

		}

		dash = strrchr(machine,'-');

		cfgmeta->flavor = cfghost;

		if ((dash && !strcmp(dash,"-bsd")) || strstr(machine,"-bsd-"))

			host->flavor = "bsd";

		else if ((dash && !strcmp(dash,"-cygwin")) || strstr(machine,"-cygwin-"))

			host->flavor = "cygwin";

		else if ((dash && !strcmp(dash,"-darwin")) || strstr(machine,"-darwin"))

			host->flavor = "darwin";

		else if ((dash && !strcmp(dash,"-linux")) || strstr(machine,"-linux-"))

			host->flavor = "linux";

		else if ((dash && !strcmp(dash,"-midipix")) || strstr(machine,"-midipix-"))

			host->flavor = "midipix";

		else if ((dash && !strcmp(dash,"-mingw")) || strstr(machine,"-mingw-"))

			host->flavor = "mingw";

		else if ((dash && !strcmp(dash,"-mingw32")) || strstr(machine,"-mingw32-"))

			host->flavor = "mingw";

		else if ((dash && !strcmp(dash,"-mingw64")) || strstr(machine,"-mingw64-"))

			host->flavor = "mingw";

		else if ((dash && !strcmp(dash,"-windows")) || strstr(machine,"-windows-"))

			host->flavor = "mingw";

		else {

			host->flavor   = "default";

			cfgmeta->flavor = "fallback, unverified";

		}

		if (fcompiler && !fnative)

			if ((mark = strstr(drvhost->machine,host->flavor)))

				if (mark > drvhost->machine)

					fnative = (*--mark == '-');

	}

	/* toollen */

	toollen =  fnative ? 0 : strlen(host->host);

	toollen += strlen("-utility-name");

	/* ar */

	if (host->ar)

		cfgmeta->ar = cfgmeta_ar ? cfgmeta_ar : cfgexplicit;

	else {

		if (!(drvhost->ar = calloc(1,toollen)))

			return -1;

		if (fnative) {

			strcpy(drvhost->ar,"ar");

			cfgmeta->ar = cfgnative;

			arprobe = 0;

		} else if (cctx->mode == SLBT_MODE_LINK) {

			arprobe = true;

		} else if (cctx->mode == SLBT_MODE_INFO) {

			arprobe = true;

		} else {

			arprobe = false;

		}

		/* arprobe */

		if (arprobe) {

			sprintf(drvhost->ar,"%s-ar",host->host);

			cfgmeta->ar = cfghost;

			ecode       = 127;

			/* empty archive */

			if ((arfd = mkstemp(archivename)) >= 0) {

				slbt_dprintf(arfd,"!<arch>\n");

				arprobeargv[0] = drvhost->ar;

				arprobeargv[1] = "-t";

				arprobeargv[2] = archivename;

				arprobeargv[3] = 0;

				/* <target>-ar */

				slbt_spawn_ar(

					arprobeargv,

					&ecode);

			}

			/* <target>-<compiler>-ar */

			if (ecode && !strchr(base,'-')) {

				sprintf(drvhost->ar,"%s-%s-ar",host->host,base);

				slbt_spawn_ar(

					arprobeargv,

					&ecode);

			}

			/* <compiler>-ar */

			if (ecode && !strchr(base,'-')) {

				sprintf(drvhost->ar,"%s-ar",base);

				slbt_spawn_ar(

					arprobeargv,

					&ecode);

			}

			/* if target is the native target, fallback to native ar */

			if (ecode && !strcmp(host->host,SLBT_MACHINE)) {

				strcpy(drvhost->ar,"ar");

				cfgmeta->ar = cfgnative;

			}

			/* fdcwd */

			fdcwd = slbt_driver_fdcwd(dctx);

			/* clean up */

			if (arfd >= 0) {

				unlinkat(fdcwd,archivename,0);

				close(arfd);

			}

		}

		host->ar = drvhost->ar;

	}

	/* ranlib */

	if (host->ranlib)

		cfgmeta->ranlib = cfgmeta_ranlib ? cfgmeta_ranlib : cfgexplicit;

	else {

		if (!(drvhost->ranlib = calloc(1,toollen)))

			return -1;

		if (fnative) {

			strcpy(drvhost->ranlib,"ranlib");

			cfgmeta->ranlib = cfgnative;

		} else {

			sprintf(drvhost->ranlib,"%s-ranlib",host->host);

			cfgmeta->ranlib = cfghost;

		}

		host->ranlib = drvhost->ranlib;

	}

	/* windres */

	if (host->windres)

		cfgmeta->windres = cfgexplicit;

	else if (strcmp(host->flavor,"cygwin")

			&& strcmp(host->flavor,"midipix")

			&& strcmp(host->flavor,"mingw")) {

		host->windres    = "";

		cfgmeta->windres = "not applicable";

	} else {

		if (!(drvhost->windres = calloc(1,toollen)))

			return -1;

		if (fnative) {

			strcpy(drvhost->windres,"windres");

			cfgmeta->windres = cfgnative;

		} else {

			sprintf(drvhost->windres,"%s-windres",host->host);

			cfgmeta->windres = cfghost;

		}

		host->windres = drvhost->windres;

	}

	/* dlltool */

	if (host->dlltool)

		cfgmeta->dlltool = cfgexplicit;

	else if (strcmp(host->flavor,"cygwin")

			&& strcmp(host->flavor,"midipix")

			&& strcmp(host->flavor,"mingw")) {

		host->dlltool = "";

		cfgmeta->dlltool = "not applicable";

	} else {

		if (!(drvhost->dlltool = calloc(1,toollen)))

			return -1;

		if (fnative) {

			strcpy(drvhost->dlltool,"dlltool");

			cfgmeta->dlltool = cfgnative;

		} else {

			sprintf(drvhost->dlltool,"%s-dlltool",host->host);

			cfgmeta->dlltool = cfghost;

		}

		host->dlltool = drvhost->dlltool;

	}

	/* mdso */

	if (host->mdso)

		cfgmeta->mdso = cfgexplicit;

	else if (strcmp(host->flavor,"cygwin")

			&& strcmp(host->flavor,"midipix")

			&& strcmp(host->flavor,"mingw")) {

		host->mdso = "";

		cfgmeta->mdso = "not applicable";

	} else {

		if (!(drvhost->mdso = calloc(1,toollen)))

			return -1;

		if (fnative) {

			strcpy(drvhost->mdso,"mdso");

			cfgmeta->mdso = cfgnative;

		} else {

			sprintf(drvhost->mdso,"%s-mdso",host->host);

			cfgmeta->mdso = cfghost;

		}

		host->mdso = drvhost->mdso;

	}

	return 0;

}

void slbt_free_host_params(struct slbt_host_strs * host)

{

	if (host->machine)

		free(host->machine);

	if (host->host)

		free(host->host);

	if (host->flavor)

		free(host->flavor);

	if (host->ar)

		free(host->ar);

	if (host->ranlib)

		free(host->ranlib);

	if (host->windres)

		free(host->windres);

	if (host->dlltool)

		free(host->dlltool);

	if (host->mdso)

		free(host->mdso);

	memset(host,0,sizeof(*host));

}

void slbt_init_flavor_settings(

	struct slbt_common_ctx *	cctx,

	const struct slbt_host_params * ahost,

	struct slbt_flavor_settings *	psettings)

{

	const struct slbt_host_params *     host;

	const struct slbt_flavor_settings * settings;

	host = ahost ? ahost : &cctx->host;

	if (!strcmp(host->flavor,"midipix"))

		settings = &host_flavor_midipix;

	else if (!strcmp(host->flavor,"mingw"))

		settings = &host_flavor_mingw;

	else if (!strcmp(host->flavor,"cygwin"))

		settings = &host_flavor_cygwin;

	else if (!strcmp(host->flavor,"darwin"))

		settings = &host_flavor_darwin;

	else

		settings = &host_flavor_default;

	if (!ahost) {

		if (!strcmp(settings->imagefmt,"elf"))

			cctx->drvflags |= SLBT_DRIVER_IMAGE_ELF;

		else if (!strcmp(settings->imagefmt,"pe"))

			cctx->drvflags |= SLBT_DRIVER_IMAGE_PE;

		else if (!strcmp(settings->imagefmt,"macho"))

			cctx->drvflags |= SLBT_DRIVER_IMAGE_MACHO;

	}

	memcpy(psettings,settings,sizeof(*settings));

	if (cctx->shrext)

		psettings->dsosuffix = cctx->shrext;

}

int slbt_init_ldrpath(

	struct slbt_common_ctx *  cctx,

	struct slbt_host_params * host)

{

	char *         buf;

	const char **  ldrpath;

	if (!cctx->rpath || !(cctx->drvflags & SLBT_DRIVER_IMAGE_ELF)) {

		host->ldrpath = 0;

		return 0;

	}

	/* common? */

	for (ldrpath=ldrpath_elf; *ldrpath; ldrpath ++)

		if (!(strcmp(cctx->rpath,*ldrpath))) {

			host->ldrpath = 0;

			return 0;

		}

	/* buf */

	if (!(buf = malloc(12 + strlen(cctx->host.host))))

		return -1;

	/* /usr/{host}/lib */

	sprintf(buf,"/usr/%s/lib",cctx->host.host);

	if (!(strcmp(cctx->rpath,buf))) {

		host->ldrpath = 0;

		free(buf);

		return 0;

	}

	/* /usr/{host}/lib64 */

	sprintf(buf,"/usr/%s/lib64",cctx->host.host);

	if (!(strcmp(cctx->rpath,buf))) {

		host->ldrpath = 0;

		free(buf);

		return 0;

	}

	host->ldrpath = cctx->rpath;

	free(buf);

	return 0;

}

void slbt_reset_alternate_host(const struct slbt_driver_ctx * ctx)

{

	struct slbt_driver_ctx_alloc *	ictx;

	uintptr_t			addr;

	addr = (uintptr_t)ctx - offsetof(struct slbt_driver_ctx_alloc,ctx);

	addr = addr - offsetof(struct slbt_driver_ctx_impl,ctx);

	ictx = (struct slbt_driver_ctx_alloc *)addr;

	slbt_free_host_params(&ictx->ctx.ahost);

}

int  slbt_set_alternate_host(

	const struct slbt_driver_ctx *	ctx,

	const char *			host,

	const char *			flavor)

{

	struct slbt_driver_ctx_alloc *	ictx;

	uintptr_t			addr;

	addr = (uintptr_t)ctx - offsetof(struct slbt_driver_ctx_alloc,ctx);

	addr = addr - offsetof(struct slbt_driver_ctx_impl,ctx);

	ictx = (struct slbt_driver_ctx_alloc *)addr;

	slbt_free_host_params(&ictx->ctx.ahost);

	if (!(ictx->ctx.ahost.host = strdup(host)))

		return SLBT_SYSTEM_ERROR(ctx,0);

	if (!(ictx->ctx.ahost.flavor = strdup(flavor))) {

		slbt_free_host_params(&ictx->ctx.ahost);

		return SLBT_SYSTEM_ERROR(ctx,0);

	}

	ictx->ctx.cctx.ahost.host   = ictx->ctx.ahost.host;

	ictx->ctx.cctx.ahost.flavor = ictx->ctx.ahost.flavor;

	if (slbt_init_host_params(

			0,

			ctx->cctx,

			&ictx->ctx.ahost,

			&ictx->ctx.cctx.ahost,

			&ictx->ctx.cctx.acfgmeta,

			0,0)) {

		slbt_free_host_params(&ictx->ctx.ahost);

		return SLBT_CUSTOM_ERROR(ctx,SLBT_ERR_HOST_INIT);

	}

	slbt_init_flavor_settings(

		&ictx->ctx.cctx,

		&ictx->ctx.cctx.ahost,

		&ictx->ctx.cctx.asettings);

	if (slbt_init_ldrpath(

			&ictx->ctx.cctx,

			&ictx->ctx.cctx.ahost)) {

		slbt_free_host_params(&ictx->ctx.ahost);

		return SLBT_CUSTOM_ERROR(ctx,SLBT_ERR_LDRPATH_INIT);

	}

	return 0;

}

int slbt_get_flavor_settings(

	const char *                            flavor,

	const struct slbt_flavor_settings **    settings)

{

	if (!strcmp(flavor,"midipix"))

		*settings = &host_flavor_midipix;

	else if (!strcmp(flavor,"mingw"))

		*settings = &host_flavor_mingw;

	else if (!strcmp(flavor,"cygwin"))

		*settings = &host_flavor_cygwin;

	else if (!strcmp(flavor,"darwin"))

		*settings = &host_flavor_darwin;

	else if (!strcmp(flavor,"default"))

		*settings = &host_flavor_default;

	else

		*settings = 0;

	return *settings ? 0 : -1;

}