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

/*  ntux: native translation und extension                 */

/*  Copyright (C) 2016--2018  Z. Gilboa                    */

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

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

#include <ntapi/ntapi.h>

#include <psxscl/psxscl.h>

#include <psxabi/sys_fcntl.h>

#include <stdint.h>

#include <ntux/ntux.h>

#include "ntux_init_impl.h"

#include "ntux_nolibc_impl.h"

#define ARGV_DRIVER

#include "ntux_version.h"

#include "ntux_driver_impl.h"

#include "argv/argv.h"

/* framework integration */

#include <psxtypes/section/midipix.h>

__attr_section_decl__(".midipix")

static const nt_tty_affiliation tty_affiliation

	__attr_section__(".midipix")

	= NT_TTY_AFFILIATION_DEFAULT;

/* ntapi accessor table */

const ntapi_vtbl * ntux_ntapi;

/* ntux command names */

static const char * const ntux_cmd_name[NTUX_CMD_CAP] = {

	[NTUX_CMD_STAT]       = "stat",

	[NTUX_CMD_SPAWN]      = "spawn",

	[NTUX_CMD_STRACE]     = "strace",

};

/* ntux command options */

static const struct argv_option * ntux_cmd_options[NTUX_CMD_CAP] = {

	[NTUX_CMD_DEFAULT]    = ntux_default_options,

	[NTUX_CMD_STAT]       = ntux_default_options,

	[NTUX_CMD_SPAWN]      = ntux_spawn_options,

	[NTUX_CMD_STRACE]     = ntux_strace_options,

};

/* package info */

static const struct ntux_source_version ntux_src_version = {

	NTUX_TAG_VER_MAJOR,

	NTUX_TAG_VER_MINOR,

	NTUX_TAG_VER_PATCH,

	NTUX_GIT_VERSION

};

struct ntux_driver_ctx_alloc {

	struct argv_meta *		meta;

	struct ntux_driver_ctx_impl	ctx;

	uint64_t			guard;

	const char *			units[];

};

static uint32_t ntux_argv_flags(uint32_t flags)

{

	uint32_t ret = 0;

	if (flags & NTUX_DRIVER_VERBOSITY_NONE)

		ret |= ARGV_VERBOSITY_NONE;

	if (flags & NTUX_DRIVER_VERBOSITY_ERRORS)

		ret |= ARGV_VERBOSITY_ERRORS;

	if (flags & NTUX_DRIVER_VERBOSITY_STATUS)

		ret |= ARGV_VERBOSITY_STATUS;

	return ret;

}

static int ntux_driver_usage(

	int				fdout,

	const char *			program,

	const char *			arg,

	const struct argv_option **	optv,

	struct argv_meta *		meta,

	enum ntux_cmd			cmd)

{

	char		header[512];

	char *		cmdarg[2];

	const char *	cmdname;

	if (cmd == NTUX_CMD_DEFAULT) {

		cmdarg[0] = "";

		cmdarg[1] = "";

		cmdname   = "";

	} else {

		cmdarg[0] = " (--cmd=";

		cmdarg[1] = ")";

		cmdname   = ntux_cmd_name[cmd];

	}

	snprintf(header,sizeof(header),

		"Usage: %s [options] ...\n"

		"Usage: %s [options] [--cmd=<command>] <arg> <arg> ...\n\n"

		"Notes: --cmd must precede all non-option arguments, as well as\n"

		"       all arguments that are specific to the selected command;\n"

		"       for commands that spawn other programs (e.g. spawn, strace),\n"

		"       the first non-option argument must specify the name of the\n"

		"       program to be executed.\n\n"

		"Options%s%s%s:\n",

		program,program,cmdarg[0],cmdname,cmdarg[1]);

	argv_usage(fdout,header,optv,arg);

	argv_free(meta);

	return NTUX_USAGE;

}

static struct ntux_driver_ctx_impl * ntux_driver_ctx_alloc(

	struct argv_meta *		meta,

	const struct ntux_fd_ctx *	fdctx,

	const struct ntux_common_ctx *	cctx,

	size_t				nunits)

{

	struct ntux_driver_ctx_alloc *	ictx;

	size_t				size;

	struct argv_entry *		entry;

	const char **			units;

	int				elements;

	(void)tty_affiliation;

	size =  sizeof(struct ntux_driver_ctx_alloc);

	size += (nunits+1)*sizeof(const char *);

	if (!(ictx = calloc(1,size)))

		return 0;

	elements = sizeof(ictx->ctx.erribuf) / sizeof(*ictx->ctx.erribuf);

	ictx->ctx.errinfp  = &ictx->ctx.erriptr[0];

	ictx->ctx.erricap  = &ictx->ctx.erriptr[--elements];

	memcpy(&ictx->ctx.fdctx,fdctx,sizeof(*fdctx));

	memcpy(&ictx->ctx.cctx,cctx,sizeof(*cctx));

	for (entry=meta->entries,units=ictx->units; entry->fopt || entry->arg; entry++)

		if (!entry->fopt)

			*units++ = entry->arg;

	ictx->meta = meta;

	ictx->ctx.ctx.units = ictx->units;

	ictx->ctx.ctx.errv  = ictx->ctx.errinfp;

	return &ictx->ctx;

}

static int ntux_cctx_update(

	const char *			program,

	const struct argv_option **	optv,

	struct argv_meta *		meta,

	uint32_t			flags,

	const struct ntux_fd_ctx *	fdctx,

	struct ntux_common_ctx *	cctx,

	size_t *			nunits)

{

	struct argv_entry *		entry;

	/* get options, count units */

	for (entry=meta->entries; entry->fopt || entry->arg; entry++) {

		if (entry->fopt) {

			switch (entry->tag) {

				case TAG_HELP:

					if (flags & NTUX_DRIVER_VERBOSITY_USAGE)

						return ntux_driver_usage(

							fdctx->fdout,

							program,entry->arg,

							optv,0,cctx->cmd);

				case TAG_VERSION:

					cctx->drvflags |= NTUX_DRIVER_VERSION;

					break;

				case TAG_CMD:

					if (*nunits)

						return ntux_driver_usage(

							fdctx->fderr,

							program,entry->arg,

							optv,0,cctx->cmd);

					if (!strcmp(entry->arg,"stat"))

						cctx->cmd = NTUX_CMD_STAT;

					else if (!strcmp(entry->arg,"spawn"))

						cctx->cmd = NTUX_CMD_SPAWN;

					else if (!strcmp(entry->arg,"strace"))

						cctx->cmd = NTUX_CMD_STRACE;

					break;

				case TAG_LOADER:

					cctx->loader = entry->arg;

					break;

				case TAG_LOGFILE:

					cctx->logfile = entry->arg;

					break;

			}

		} else {

			(*nunits)++;

		}

	}

	return 0;

}

static int ntux_get_driver_ctx_fail(struct argv_meta * meta)

{

	argv_free(meta);

	return -1;

}

static int ntux_cmd_from_program(const char * program)

{

	const char *	dot;

	const char *	hyphen;

	const char *	mark;

	dot    = strrchr(program,'.');

	hyphen = strrchr(program,'-');

	if (hyphen > dot)

		mark = ++hyphen;

	else if (dot > hyphen)

		mark = ++dot;

	else

		mark = program;

	if (!strcmp(mark,"stat"))

		return NTUX_CMD_STAT;

	else if (!strcmp(mark,"spawn"))

		return NTUX_CMD_SPAWN;

	else if (!strcmp(mark,"strace"))

		return NTUX_CMD_STRACE;

	return NTUX_CMD_DEFAULT;

}

int ntux_get_driver_ctx(

	char **				argv,

	char **				envp,

	uint32_t			flags,

	const struct ntux_fd_ctx *	fdctx,

	struct ntux_driver_ctx **	pctx)

{

	struct ntux_driver_ctx_impl *	ictx;

	struct ntux_common_ctx		cctx;

	const struct argv_option *	optv[NTUX_OPTV_ELEMENTS];

	struct argv_meta *		meta;

	size_t				nunits;

	const char *			program;

	char **				parg;

	char **				cmdargv;

	char *				cmdmark;

	char **				execargv;

	char *				execarg;

	struct argv_ctx			ctx = {ARGV_VERBOSITY_NONE,

                                               ARGV_MODE_SCAN,

                                               0,0,0,0,0,0,0};

	/* init */

	if (ntux_init())

		return -1;

	/* fdctx */

	if (!fdctx) {

		fdctx = &(const struct ntux_fd_ctx) {

			.fdin  = STDIN_FILENO,

			.fdout = STDOUT_FILENO,

			.fderr = STDERR_FILENO,

			.fdlog = (-1),

			.fdcwd = AT_FDCWD,

			.fddst = AT_FDCWD,

		};

	}

	/* cctx */

	memset(&cctx,0,sizeof(cctx));

	nunits	      = 0;

	execargv      = 0;

	program       = argv_program_name(argv[0]);

	cctx.cmd      = ntux_cmd_from_program(program);

	cctx.drvflags = flags;

	/* missing arguments? */

	argv_optv_init(ntux_cmd_options[cctx.cmd],optv);

	if (!argv[1] && (flags & NTUX_DRIVER_VERBOSITY_USAGE))

		return ntux_driver_usage(

			fdctx->fderr,

			program,0,

			optv,0,cctx.cmd);

	/* initial argv scan: ... --cmd=xxx ... */

	for (parg=argv, cmdargv=0; *parg && !cmdargv; parg++) {

		if (!strcmp(*parg,"--cmd") && parg[1]) {

				cmdargv = &parg[2];

				cmdmark = parg[2];

		} else if (!strncmp(*parg,"--cmd=",6)) {

				cmdargv = &parg[1];

				cmdmark = parg[1];

		}

	}

	/* process argv entries preceding --cmd */

	if (cmdargv) {

		*cmdargv = 0;

		if (!(meta = argv_get(

				argv,optv,

				ntux_argv_flags(flags),

				fdctx->fderr)))

			return -1;

		if (ntux_cctx_update(

				program,optv,meta,flags,

				fdctx,&cctx,&nunits)) {

			argv_free(meta);

			return -1;

		}

		*cmdargv-- = cmdmark;

		*cmdargv   = argv[0];

		argv       = cmdargv;

	}

	/* set option vector by command */

	if (cctx.cmd == NTUX_CMD_SPAWN)

		argv_optv_init(ntux_spawn_options,optv);

	else if (cctx.cmd == NTUX_CMD_STRACE)

		argv_optv_init(ntux_strace_options,optv);

	/* spawn, strace */

	if ((cctx.cmd == NTUX_CMD_SPAWN) || (cctx.cmd == NTUX_CMD_STRACE)) {

		argv_scan(argv,optv,&ctx,0);

		if (ctx.erridx && !ctx.unitidx) {

			if (flags & NTUX_DRIVER_VERBOSITY_ERRORS)

				argv_get(

					argv,optv,

					ntux_argv_flags(flags),

					fdctx->fderr);

			return -1;

		}

		if (!ctx.unitidx && (flags & NTUX_DRIVER_VERBOSITY_USAGE))

			ntux_driver_usage(

				fdctx->fderr,

				program,0,

				optv,0,cctx.cmd);

		if (!ctx.unitidx)

			return NTUX_ERROR;

		execargv  = &argv[ctx.unitidx];

		execarg   = argv[ctx.unitidx];

		*execargv = 0;

	}

	/* obtain ntux's own arguments */

	if (!(meta = argv_get(

			argv,optv,

			ntux_argv_flags(flags),

			fdctx->fderr)))

		return -1;

	if (ntux_cctx_update(

			program,optv,meta,flags,

			fdctx,&cctx,&nunits)) {

		argv_free(meta);

		return -1;

	}

	/* spawn, strace: exec argv */

	if (execargv) {

		*execargv  = execarg;

		cctx.sargv = execargv;

		cctx.senvp = envp;

		nunits     = 0;

	}

	/* finalize */

	if (nunits && !cctx.cmd)

		return ntux_driver_usage(

			fdctx->fderr,

			program,0,

			optv,meta,

			NTUX_CMD_DEFAULT);

	if (!(ictx = ntux_driver_ctx_alloc(meta,fdctx,&cctx,nunits)))

		return ntux_get_driver_ctx_fail(meta);

	ictx->ctx.program = program;

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

	*pctx             = &ictx->ctx;

	return 0;

}

static void ntux_free_driver_ctx_impl(struct ntux_driver_ctx_alloc * ictx)

{

	argv_free(ictx->meta);

	free(ictx);

}

void ntux_free_driver_ctx(struct ntux_driver_ctx * ctx)

{

	struct ntux_driver_ctx_alloc *	ictx;

	uintptr_t			addr;

	if (ctx) {

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

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

		ictx = (struct ntux_driver_ctx_alloc *)addr;

		ntux_free_driver_ctx_impl(ictx);

	}

}

const struct ntux_source_version * ntux_source_version(void)

{

	return &ntux_src_version;

}

int ntux_get_driver_fdctx(

	const struct ntux_driver_ctx *	dctx,

	struct ntux_fd_ctx *		fdctx)

{

	struct ntux_driver_ctx_impl *	ictx;

	ictx = ntux_get_driver_ictx(dctx);

	fdctx->fdin  = ictx->fdctx.fdin;

	fdctx->fdout = ictx->fdctx.fdout;

	fdctx->fderr = ictx->fdctx.fderr;

	fdctx->fdlog = ictx->fdctx.fdlog;

	fdctx->fdcwd = ictx->fdctx.fdcwd;

	fdctx->fddst = ictx->fdctx.fddst;

	return 0;

}

int ntux_set_driver_fdctx(

	struct ntux_driver_ctx *	dctx,

	const struct ntux_fd_ctx *	fdctx)

{

	struct ntux_driver_ctx_impl *	ictx;

	ictx = ntux_get_driver_ictx(dctx);

	ictx->fdctx.fdin  = fdctx->fdin;

	ictx->fdctx.fdout = fdctx->fdout;

	ictx->fdctx.fderr = fdctx->fderr;

	ictx->fdctx.fdlog = fdctx->fdlog;

	ictx->fdctx.fdcwd = fdctx->fdcwd;

	ictx->fdctx.fddst = fdctx->fddst;

	return 0;

}