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

/*  perk: PE Resource Kit                                      */

/*  Copyright (C) 2015--2016  Z. Gilboa                        */

/*  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_driver_impl.h"

#include "argv/argv.h"

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 = 0;

	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(

	const char *			program,

	const char *			arg,

	const struct argv_option *	options,

	struct argv_meta *		meta)

{

	char header[512];

	snprintf(header,sizeof(header),

		"Usage: %s [options] <file>...\n" "Options:\n",

		program);

	argv_usage(stdout,header,options,arg);

	argv_free(meta);

	return PERK_USAGE;

}

static struct pe_driver_ctx_impl * pe_driver_ctx_alloc(

	struct argv_meta *		meta,

	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;

	size =  sizeof(struct pe_driver_ctx_alloc);

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

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

		return 0;

	if (cctx)

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

	ictx->meta		= meta;

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

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

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

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

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

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

		if (!entry->fopt)

			*units++ = entry->arg;

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

	return &ictx->ctx;

}

static int pe_get_driver_ctx_fail(struct argv_meta * meta)

{

	argv_free(meta);

	return -1;

}

int pe_get_driver_ctx(

	char **			argv,

	char **			envp,

	uint32_t		flags,

	struct pe_driver_ctx ** pctx)

{

	struct pe_driver_ctx_impl *	ctx;

	struct pe_common_ctx		cctx;

	const struct argv_option *	options;

	struct argv_meta *		meta;

	struct argv_entry *		entry;

	size_t				nunits;

	const char *			program;

	const char *			pretty;

	int				fdout;

	options = pe_default_options;

	if (!(meta = argv_get(argv,options,pe_argv_flags(flags))))

		return -1;

	pretty	= 0;

	nunits	= 0;

	fdout	= 0;

	program = argv_program_name(argv[0]);

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

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

		return pe_driver_usage(program,0,options,meta);

	/* get options, count units */

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

		if (entry->fopt) {

			switch (entry->tag) {

				case TAG_HELP:

					if (flags & PERK_DRIVER_VERBOSITY_USAGE)

						return pe_driver_usage(program,entry->arg,options,meta);

				case TAG_VERSION:

					cctx.drvflags |= PERK_DRIVER_VERSION;

					break;

				case TAG_OUTPUT:

					cctx.output = entry->arg;

					break;

				case TAG_PRETTY:

					pretty = entry->arg;

					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;

			}

		} else

			nunits++;

	}

	if (cctx.output && ((fdout = open(cctx.output,

			O_CREAT|O_TRUNC|O_WRONLY|O_NOCTTY|O_NOFOLLOW,

			S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH)) < 0))

		return pe_get_driver_ctx_fail(meta);

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

		cctx.fmtflags |= PERK_PRETTY_YAML;

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

		cctx.fmtflags |= PERK_PRETTY_DLLTOOL;

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

		close(fdout);

	if (!ctx)

		return pe_get_driver_ctx_fail(meta);

	ctx->ctx.program	= program;

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

	ctx->ioctx.fdout	= cctx.output ? fdout : -1;

	ctx->ioctx.fdin		= -1;

	ctx->ioctx.fderr	= -1;

	ctx->ioctx.fdlog	= -1;

	ctx->ioctx.fdsrc	= AT_FDCWD;

	ctx->ioctx.fddst	= AT_FDCWD;

	ctx->ioctx.fdtmp	= AT_FDCWD;

	*pctx = &ctx->ctx;

	return PERK_OK;

}

static void pe_driver_close_fds(struct pe_common_ctx * cctx)

{

	if (cctx->ioctx->status && cctx->output)

		unlinkat(cctx->ioctx->fddst,cctx->output,0);

	if (cctx->ioctx->fdout >= 0)

		close(cctx->ioctx->fdout);

}

static void pe_free_driver_ctx_impl(struct pe_driver_ctx_alloc * ictx)

{

	if (ictx->ctx.symctx.append)

		free(ictx->ctx.symctx.append);

	if (ictx->ctx.symctx.exclude)

		free(ictx->ctx.symctx.exclude);

	pe_driver_close_fds(&ictx->ctx.cctx);

	argv_free(ictx->meta);

	free(ictx);

}

void pe_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_alloc,ctx);

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

		ictx = (struct pe_driver_ctx_alloc *)addr;

		pe_free_driver_ctx_impl(ictx);

	}

}