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

/*  mdso: midipix dso scavenger                                 */

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

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

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

#include <stdint.h>

#include <unistd.h>

#include <fcntl.h>

#include <stdbool.h>

#include <string.h>

#include <sys/stat.h>

#define ARGV_DRIVER

#include <mdso/mdso.h>

#include <mdso/mdso_output.h>

#include <mdso/mdso_specs.h>

#include "mdso_driver_impl.h"

#include "argv/argv.h"

struct mdso_driver_ctx_alloc {

	struct argv_meta *		meta;

	struct mdso_driver_ctx_impl	ctx;

	uint64_t			guard;

	const char *			units[];

};

static uint32_t mdso_argv_flags(uint32_t flags)

{

	uint32_t ret = 0;

	if (flags & MDSO_DRIVER_VERBOSITY_NONE)

		ret |= ARGV_VERBOSITY_NONE;

	if (flags & MDSO_DRIVER_VERBOSITY_ERRORS)

		ret |= ARGV_VERBOSITY_ERRORS;

	if (flags & MDSO_DRIVER_VERBOSITY_STATUS)

		ret |= ARGV_VERBOSITY_STATUS;

	return ret;

}

static int mdso_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 MDSO_USAGE;

}

static struct mdso_driver_ctx_impl * mdso_driver_ctx_alloc(

	struct argv_meta *		meta,

	const struct mdso_common_ctx *	cctx,

	size_t				nunits)

{

	struct mdso_driver_ctx_alloc *	ictx;

	size_t				size;

	struct argv_entry *		entry;

	const char **			units;

	size =  sizeof(struct mdso_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));

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

		if (!entry->fopt)

			*units++ = entry->arg;

	ictx->meta = meta;

	ictx->ctx.fdtmpin = -1;

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

	return &ictx->ctx;

}

static int mdso_dstdir_open(const struct mdso_common_ctx * cctx, const char * asmbase)

{

	int fdtop;

	int fddst;

	const int dirmode = S_IRUSR|S_IWUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH;

	if ((fdtop = openat(AT_FDCWD,cctx->dstdir,O_DIRECTORY)) < 0) {

		if (mkdirat(AT_FDCWD,cctx->dstdir,dirmode) < 0)

			return -1;

		else if ((fdtop = openat(AT_FDCWD,cctx->dstdir,O_DIRECTORY)) < 0)

			return -1;

	}

	if ((fddst = openat(fdtop,asmbase,O_DIRECTORY)) < 0) {

		if (mkdirat(fdtop,asmbase,dirmode) < 0)

			return -1;

		else if ((fddst = openat(fdtop,asmbase,O_DIRECTORY)) < 0)

			return -1;

	}

	close(fdtop);

	return fddst;

}

static int mdso_get_driver_ctx_fail(

	struct argv_meta *	meta,

	char *			asmbase,

	int			fddst)

{

	if (fddst >= 0)

		close(fddst);

	if (asmbase)

		free(asmbase);

	argv_free(meta);

	return -1;

}

int mdso_get_driver_ctx(

	char **			argv,

	char **			envp,

	uint32_t		flags,

	struct mdso_driver_ctx ** pctx)

{

	struct mdso_driver_ctx_impl *	ctx;

	struct mdso_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;

	char *				asmbase;

	char *				dot;

	int				fddst;

	options = mdso_default_options;

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

		return -1;

	nunits	= 0;

	pretty	= 0;

	asmbase = 0;

	fddst	= -1;

	program = argv_program_name(argv[0]);

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

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

		return mdso_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 & MDSO_DRIVER_VERBOSITY_USAGE)

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

				case TAG_VERSION:

					cctx.drvflags |= MDSO_DRIVER_VERSION;

					break;

				case TAG_QUAD_PTR:

					cctx.drvflags |= MDSO_DRIVER_QUAD_PTR;

					break;

				case TAG_LIBPATH:

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

						cctx.dsoflags |= MDSO_FLAG_LOADER_PATH;

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

						cctx.dsoflags |= MDSO_FLAG_PEB_PATH;

					if (!(strcmp(entry->arg,"system32")))

						cctx.dsoflags |= MDSO_FLAG_SYSTEM32;

					break;

				case TAG_LIBNAME:

					cctx.libname = entry->arg;

					break;

				case TAG_DSTDIR:

					cctx.dstdir = entry->arg;

					break;

				case TAG_PRETTY:

					pretty = entry->arg;

					break;

				case TAG_EXPSYMS:

					cctx.fmtflags |= MDSO_OUTPUT_EXPORT_SYMS;

					break;

			}

		} else

			nunits++;

	}

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

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

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

		cctx.fmtflags |= MDSO_PRETTY_YAML;

	if (!cctx.libname)

		cctx.libname = "win32any";

	if (!(asmbase = strdup(cctx.libname)))

		return mdso_get_driver_ctx_fail(meta,asmbase,fddst);

	if ((dot = strchr(asmbase,'.')))

		*dot = '\0';

	if (cctx.dstdir && (fddst = mdso_dstdir_open(&cctx,asmbase)) < 0)

		return mdso_get_driver_ctx_fail(meta,asmbase,fddst);

	if (!(ctx = mdso_driver_ctx_alloc(meta,&cctx,nunits)))

		return mdso_get_driver_ctx_fail(meta,asmbase,fddst);

	ctx->asmbase		= asmbase;

	ctx->cctx.asmbase	= asmbase;

	ctx->fddst		= fddst;

	ctx->ctx.program	= program;

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

	*pctx = &ctx->ctx;

	return MDSO_OK;

}

int mdso_create_driver_ctx(

	const struct mdso_common_ctx *	cctx,

	struct mdso_driver_ctx **	pctx)

{

	struct argv_meta *		meta;

	struct mdso_driver_ctx_impl *	ctx;

	int				fddst  = -1;

	char *				argv[] = {"mdso_driver",0};

	if (!(meta = argv_get(argv,mdso_default_options,0)))

		return -1;

	if (cctx->dstdir && (fddst = mdso_dstdir_open(cctx,cctx->asmbase)) < 0)

		return mdso_get_driver_ctx_fail(meta,0,fddst);

	if (!(ctx = mdso_driver_ctx_alloc(meta,cctx,0)))

		return mdso_get_driver_ctx_fail(meta,0,fddst);

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

	*pctx = &ctx->ctx;

	return MDSO_OK;

}

static void mdso_free_driver_ctx_impl(struct mdso_driver_ctx_alloc * ictx)

{

	if (ictx->ctx.fddst >= 0)

		close(ictx->ctx.fddst);

	if (ictx->ctx.fdtmpin >= 0)

		close(ictx->ctx.fdtmpin);

	if (ictx->ctx.asmbase)

		free(ictx->ctx.asmbase);

	argv_free(ictx->meta);

	free(ictx);

}

void mdso_free_driver_ctx(struct mdso_driver_ctx * ctx)

{

	struct mdso_driver_ctx_alloc *	ictx;

	uintptr_t			addr;

	if (ctx) {

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

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

		ictx = (struct mdso_driver_ctx_alloc *)addr;

		mdso_free_driver_ctx_impl(ictx);

	}

}