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

/*  perk: PE Resource Kit                                      */

/*  Copyright (C) 2015--2021  SysDeer Technologies, LLC        */

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

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

#include <stdint.h>

#include <unistd.h>

#include <fcntl.h>

#define ARGV_DRIVER

#include <perk/perk.h>

#include <perk/perk_output.h>

#include "perk_version.h"

#include "perk_driver_impl.h"

#include "argv/argv.h"

/* package info */

static const struct pe_source_version pe_src_version = {

	PERK_TAG_VER_MAJOR,

	PERK_TAG_VER_MINOR,

	PERK_TAG_VER_PATCH,

	PERK_GIT_VERSION

};

/* perk command names */

static const char * const perk_cmd_name[PERK_CMD_CAP] = {

	[PERK_CMD_PERK]     = "perk",

};

/* perk command options */

static const struct argv_option * perk_cmd_options[PERK_CMD_CAP] = {

	[PERK_CMD_DEFAULT]  = pe_default_options,

	[PERK_CMD_PERK]     = pe_perk_options,

};

/* default fd context */

static const struct pe_fd_ctx pe_default_fdctx = {

	.fdin  = STDIN_FILENO,

	.fdout = STDOUT_FILENO,

	.fderr = STDERR_FILENO,

	.fdcwd = AT_FDCWD,

	.fddst = AT_FDCWD,

	.fdlog = (-1),

};

struct pe_driver_ctx_alloc {

	struct argv_meta *		meta;

	struct pe_driver_ctx_impl	ctx;

	uint64_t			guard;

	const char *			units[];

};

static uint32_t pe_argv_flags(uint32_t flags)

{

	uint32_t ret = ARGV_CLONE_VECTOR;

	if (flags & PERK_DRIVER_VERBOSITY_NONE)

		ret |= ARGV_VERBOSITY_NONE;

	if (flags & PERK_DRIVER_VERBOSITY_ERRORS)

		ret |= ARGV_VERBOSITY_ERRORS;

	if (flags & PERK_DRIVER_VERBOSITY_STATUS)

		ret |= ARGV_VERBOSITY_STATUS;

	return ret;

}

static int pe_driver_usage(

	int				fdout,

	const char *			program,

	const char *			arg,

	const struct argv_option **	optv,

	struct argv_meta *		meta,

	enum pe_cmd                     cmd)

{

	char		header[512];

	char *		cmdarg[2];

	const char *	cmdname;

	if (cmd == PERK_CMD_DEFAULT) {

		cmdarg[0] = "";

		cmdarg[1] = "";

		cmdname   = "";

	} else {

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

		cmdarg[1] = ")";

		cmdname   = perk_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\n"

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

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

	argv_usage(fdout,header,optv,arg);

	argv_free(meta);

	return PERK_USAGE;

}

static struct pe_driver_ctx_impl * pe_driver_ctx_alloc(

	struct argv_meta *		meta,

	const struct pe_fd_ctx *	fdctx,

	const struct pe_common_ctx *	cctx,

	size_t				nunits)

{

	struct pe_driver_ctx_alloc *	ictx;

	size_t				size;

	struct argv_entry *		entry;

	const char **			units;

	int				elements;

	size =  sizeof(struct pe_driver_ctx_alloc);

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

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

		return 0;

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

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

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

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

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

	ictx->meta = meta;

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

		if (!entry->fopt)

			*units++ = entry->arg;

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

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

	return &ictx->ctx;

}

static int pe_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,"perk")) {

		return PERK_CMD_PERK;

	} else {

		return PERK_CMD_DEFAULT;

	}

}

static int pe_cctx_update(

	const char *                    program,

	const struct argv_option **     optv,

	struct argv_meta *              meta,

	const struct pe_fd_ctx *        fdctx,

	struct pe_common_ctx *          cctx,

	size_t *                        nunits)

{

	struct argv_entry *		entry;

	const char *			pretty;

	pretty = 0;

	/* get options, count units */

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

		if (entry->fopt) {

			switch (entry->tag) {

				case TAG_HELP:

					return pe_driver_usage(

						fdctx->fdout,

						program,entry->arg,

						optv,0,cctx->cmd);

					break;

				case TAG_CMD:

					if (*nunits)

						return pe_driver_usage(

							fdctx->fderr,

							program,0,

							optv,0,cctx->cmd);

					cctx->cmd = pe_cmd_from_program(entry->arg);

					break;

				case TAG_VERSION:

					cctx->drvflags |= PERK_DRIVER_VERSION;

					break;

				case TAG_PRETTY:

					pretty = entry->arg;

					break;

				case TAG_CATEGORY:

					cctx->fmtflags |= PERK_OUTPUT_IMAGE_CATEGORY;

					break;

				case TAG_SECTIONS:

					cctx->fmtflags |= PERK_OUTPUT_IMAGE_SECTIONS;

					break;

				case TAG_SYMBOLS:

					cctx->fmtflags |= PERK_OUTPUT_IMAGE_SYMBOLS;

					break;

				case TAG_STRINGS:

					cctx->fmtflags |= PERK_OUTPUT_IMAGE_STRINGS;

					break;

				case TAG_EXPSYMS:

					cctx->fmtflags |= PERK_OUTPUT_EXPORT_SYMS;

					break;

				case TAG_IMPLIBS:

					cctx->fmtflags |= PERK_OUTPUT_IMPORT_LIBS;

					break;

				case TAG_IMPSYMS:

					cctx->fmtflags |= PERK_OUTPUT_IMPORT_SYMS;

					break;

				case TAG_DSOLIBS:

					cctx->fmtflags |= PERK_OUTPUT_MDSO_LIBS;

					break;

				case TAG_DSOSYMS:

					cctx->fmtflags |= PERK_OUTPUT_MDSO_SYMS;

					break;

				case TAG_HDRDUMP:

					if (!entry->arg) {

						cctx->hdrdump = 0;

						cctx->hdrdump = ~cctx->hdrdump;

					} else if (!strcmp(entry->arg,"dos")) {

						cctx->hdrdump  = PERK_HDRDUMP_IMAGE_DOS_HEADER;

					} else if (!strcmp(entry->arg,"image.dos")) {

						cctx->hdrdump  = PERK_HDRDUMP_IMAGE_DOS_HEADER;

					} else if (!strcmp(entry->arg,"coff")) {

						cctx->hdrdump  = PERK_HDRDUMP_COFF_IMAGE_HEADER;

						cctx->hdrdump |= PERK_HDRDUMP_COFF_OBJECT_HEADER;

						cctx->hdrdump |= PERK_HDRDUMP_COFF_OPT_HEADER;

					} else if (!strcmp(entry->arg,"coff.image")) {

						cctx->hdrdump  = PERK_HDRDUMP_COFF_IMAGE_HEADER;

					} else if (!strcmp(entry->arg,"coff.obj")) {

						cctx->hdrdump  = PERK_HDRDUMP_COFF_OBJECT_HEADER;

					} else if (!strcmp(entry->arg,"coff.object")) {

						cctx->hdrdump  = PERK_HDRDUMP_COFF_OBJECT_HEADER;

					} else if (!strcmp(entry->arg,"coff.opt")) {

						cctx->hdrdump  = PERK_HDRDUMP_COFF_OPT_HEADER;

					} else if (!strcmp(entry->arg,"coff.optional")) {

						cctx->hdrdump  = PERK_HDRDUMP_COFF_OPT_HEADER;

					} else if (!strcmp(entry->arg,"sectbl")) {

						cctx->hdrdump  = PERK_HDRDUMP_SECTION_TABLE;

					} else if (!strcmp(entry->arg,"section.table")) {

						cctx->hdrdump  = PERK_HDRDUMP_SECTION_TABLE;

					} else if (!strcmp(entry->arg,"exphdr")) {

						cctx->hdrdump  = PERK_HDRDUMP_EXPORT_HEADER;

					} else if (!strcmp(entry->arg,"export.header")) {

						cctx->hdrdump  = PERK_HDRDUMP_EXPORT_HEADER;

					} else if (!strcmp(entry->arg,"imptbl")) {

						cctx->hdrdump  = PERK_HDRDUMP_IMPORT_TABLE;

					} else if (!strcmp(entry->arg,"import.table")) {

						cctx->hdrdump  = PERK_HDRDUMP_IMPORT_TABLE;

					}

					break;

			}

		} else {

			(*nunits)++;

		}

	}

	if (pretty && !strcmp(pretty,"yaml")) {

		cctx->fmtflags |= PERK_PRETTY_YAML;

	} else if (pretty && !strcmp(pretty,"dlltool")) {

		cctx->fmtflags |= PERK_PRETTY_DLLTOOL;

	}

	return 0;

}

static int pe_lib_get_driver_ctx_fail(struct argv_meta * meta)

{

	argv_free(meta);

	return -1;

}

int pe_lib_get_driver_ctx(

	char **				argv,

	char **				envp,

	uint32_t			flags,

	const struct pe_fd_ctx *	fdctx,

	struct pe_driver_ctx ** 	pctx)

{

	struct pe_driver_ctx_impl *	ctx;

	struct pe_common_ctx		cctx;

	const struct argv_option *	optv[PERK_OPTV_ELEMENTS];

	struct argv_meta *		meta;

	size_t				nunits;

	const char *			program;

	char **				parg;

	char **				pargcap;

	char **				cmdargv;

	char *				cmdmark;

	struct argv_ctx			actx = {ARGV_VERBOSITY_NONE,

                                               ARGV_MODE_SCAN,

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

	(void)envp;

	/* fdctx */

	if (!fdctx)

		fdctx = &pe_default_fdctx;

	/* cctx */

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

	program       = argv_program_name(argv[0]);\

	cctx.cmd      = pe_cmd_from_program(program);

	cctx.drvflags = flags;

	nunits	      = 0;

	/* missing arguments? */

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

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

		return pe_driver_usage(

			fdctx->fderr,

			program,0,

			optv,0,cctx.cmd);

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

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

	/* position of last base perk argument */

	if (actx.erridx && actx.unitidx)

		pargcap = &argv[actx.unitidx];

	else if (actx.erridx)

		pargcap = &argv[actx.erridx];

	else

		for (pargcap=argv; *pargcap; pargcap++)

			(void)0;

	/* scan for --cmd */

	for (parg=argv, cmdargv=0; (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];

		}

	}

	/* invalid perk arguments? */

	if (!actx.erridx) {

		(void)0;

	} else if (&argv[actx.erridx] >= cmdargv) {

		(void)0;

	} else {

		if (flags & PERK_DRIVER_VERBOSITY_ERRORS)

			argv_get(

				argv,optv,

				ARGV_VERBOSITY_ERRORS,

				fdctx->fderr);

		return -1;

	}

	/* process argv entries preceding --cmd */

	if (cmdargv) {

		*cmdargv = 0;

		if (!(meta = argv_get(

				argv,optv,

				pe_argv_flags(flags),

				fdctx->fderr)))

			return -1;

		if (pe_cctx_update(

				program,optv,meta,

				fdctx,&cctx,&nunits)) {

			argv_free(meta);

			return -1;

		}

		argv_free(meta);

		*cmdargv-- = cmdmark;

		*cmdargv   = argv[0];

		argv       = cmdargv;

	}

	/* set option vector by command */

	if (cctx.cmd == PERK_CMD_DEFAULT) {

		argv_optv_init(pe_default_options,optv);

	} else if (cctx.cmd == PERK_CMD_PERK) {

		argv_optv_init(pe_perk_options,optv);

	}

	/* process the selected tool's command-line arguments */

	if (!(meta = argv_get(

			argv,optv,

			pe_argv_flags(flags),

			fdctx->fderr)))

		return -1;

	if (pe_cctx_update(

			program,optv,meta,

			fdctx,&cctx,&nunits)) {

		argv_free(meta);

		return -1;

	}

	/* utility mode and no action to take? */

	if (cctx.drvflags & PERK_DRIVER_VERBOSITY_UTILITY)

		if (!nunits && !(cctx.drvflags & PERK_DRIVER_VERSION))

			return pe_driver_usage(

				fdctx->fdout,

				program,0,

				optv,meta,cctx.cmd);

	/* context allocation */

	if (!(ctx = pe_driver_ctx_alloc(meta,fdctx,&cctx,nunits)))

		return pe_lib_get_driver_ctx_fail(meta);

	ctx->ctx.program	= program;

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

	*pctx = &ctx->ctx;

	return PERK_OK;

}

static void pe_lib_free_driver_ctx_impl(struct pe_driver_ctx_alloc * ictx)

{

	argv_free(ictx->meta);

	free(ictx);

}

void pe_lib_free_driver_ctx(struct pe_driver_ctx * ctx)

{

	struct pe_driver_ctx_alloc *	ictx;

	uintptr_t			addr;

	if (ctx) {

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

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

		ictx = (struct pe_driver_ctx_alloc *)addr;

		pe_lib_free_driver_ctx_impl(ictx);

	}

}

const struct pe_source_version * pe_source_version(void)

{

	return &pe_src_version;

}

int pe_lib_get_driver_fdctx(

	const struct pe_driver_ctx *	dctx,

	struct pe_fd_ctx *		fdctx)

{

	struct pe_driver_ctx_impl *	ictx;

	ictx = pe_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 pe_lib_set_driver_fdctx(

	struct pe_driver_ctx *	dctx,

	const struct pe_fd_ctx *	fdctx)

{

	struct pe_driver_ctx_impl *	ictx;

	ictx = pe_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;

}