/* $Id: cab.c,v 1.7 2021/11/06 17:35:07 khorben Exp $ */
/* Copyright (c) 2011 khorben of Uberwall */
/* This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation version 2 of the License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */



#include "plugin.h"

#define min(a, b) ((a) < (b) ? (a) : (b))


/* cab */
/* private */
/* types */
#pragma pack(1)
struct cab
{
	char signature[4];
	uint32_t reserved1;
	uint32_t cbCabinet;
	uint32_t reserved2;
	uint32_t coffFiles;
	uint32_t reserved3;
	uint8_t versionMinor;
	uint8_t versionMajor;
	uint16_t cFolders;
	uint16_t cFiles;
	uint16_t flags;
	uint16_t setID;
	uint16_t iCabinet;
};
#pragma pack()


/* protected */
/* variables */
/* magic */
static unsigned char sig[] = "MSCF";

static PluginMagic cab_magic[] =
{
	{ 0,	0,	sig,	sizeof(sig) - 1	},
	{ 0,	0,	NULL,	0		}
};


/* prototypes */
static int cab_callback(PluginHelper * ph, int signature, FILE * fp);


/* public */
/* plugin */
Plugin plugin =
{
	PT_ARCHIVE | PT_COMPRESSION,
	"CAB",
	cab_magic,
	cab_callback
};


/* protected */
/* functions */
/* cab_callback */
static int _callback_reserved(struct cab * hdr);
static void _callback_size(PluginHelper * ph, struct cab * hdr);
static int _callback_version(PluginHelper * ph, struct cab * hdr);
static void _callback_files(PluginHelper * ph, struct cab * hdr);
static int _callback_flags(PluginHelper * ph, struct cab * hdr);
static void _callback_set(PluginHelper * ph, struct cab * hdr);
static int _callback_extract(PluginHelper * ph, FILE * fp, struct cab * hdr);

static int cab_callback(PluginHelper * ph, int signature, FILE * fp)
{
	int score = 0;
	struct cab hdr;
	(void) signature;

	if(fread(&hdr, sizeof(hdr), 1, fp) != 1)
		return -1;
	score += _callback_reserved(&hdr);
	_callback_size(ph, &hdr);
	score += _callback_version(ph, &hdr);
	_callback_files(ph, &hdr);
	score += _callback_flags(ph, &hdr);
	_callback_set(ph, &hdr);
	ph->printf(ph, "\n");
	_callback_extract(ph, fp, &hdr);
	return score / 3;
}

static int _callback_reserved(struct cab * hdr)
{
	int ret = 0;

	if(hdr->reserved1 == 0)
		ret += 100;
	if(hdr->reserved2 == 0)
		ret += 100;
	if(hdr->reserved3 == 0)
		ret += 100;
	return ret / 3;
}

static void _callback_size(PluginHelper * ph, struct cab * hdr)
{
	hdr->cbCabinet = htol32(hdr->cbCabinet);
	ph->printf(ph, "size %u", hdr->cbCabinet);
}

static int _callback_version(PluginHelper * ph, struct cab * hdr)
{
	int ret = 0;

	if(hdr->versionMajor == 1)
		ret += 100;
	if(hdr->versionMinor == 3)
		ret += 100;
	else if(hdr->versionMinor <= 4)
		ret += 50;
	ph->printf(ph, ", version %u.%u", hdr->versionMajor, hdr->versionMinor);
	return ret / 2;
}

static void _callback_files(PluginHelper * ph, struct cab * hdr)
{
	hdr->cFolders = htol16(hdr->cFolders);
	hdr->cFiles = htol16(hdr->cFiles);
	ph->printf(ph, ", %u files in %u folders", hdr->cFiles, hdr->cFolders);
}

static int _callback_flags(PluginHelper * ph, struct cab * hdr)
{
	struct
	{
		unsigned int flag;
		char const * string;
	} flags[] =
	{
		{ 0x0001,	"PREV_CABINET"		},
		{ 0x0002,	"NEXT_CABINET"		},
		{ 0x0004,	"RESERVE_PRESENT"	},
		{ 0x0000,	NULL			}
	};
	size_t i;
	char const * sep = ", flags ";

	hdr->flags = htol16(hdr->flags);
	for(i = 0; flags[i].string != NULL; i++)
		if(hdr->flags & flags[i].flag)
		{
			ph->printf(ph, "%s%s", sep, flags[i].string);
			sep = "|";
		}
	return ((hdr->flags & 0x0007) == hdr->flags) ? 100 : 0;
}

static void _callback_set(PluginHelper * ph, struct cab * hdr)
{
	hdr->setID = htol16(hdr->setID);
	hdr->iCabinet = htol16(hdr->iCabinet);
	ph->printf(ph, ", set %u, number %u", hdr->setID, hdr->iCabinet);
}

static int _callback_extract(PluginHelper * ph, FILE * fp, struct cab * hdr)
{
	FILE * xfp;
	char buf[1024];
	size_t i;
	size_t s;

	if((xfp = ph->fopen(ph, "CAB")) == NULL)
		return -1;
	if(ph->fwrite(hdr, sizeof(*hdr), 1, xfp) != 1)
	{
		ph->fclose(xfp);
		return -1;
	}
	for(i = sizeof(*hdr); i < hdr->cbCabinet; i += s)
	{
		s = min(sizeof(buf), hdr->cbCabinet - i);
		if((s = fread(buf, sizeof(*buf), s, fp)) == 0)
			break;
		if(fwrite(buf, sizeof(*buf), s, xfp) != s)
			break;
		if(s < sizeof(buf))
			break;
	}
	ph->fclose(xfp);
	return (ferror(fp) || ferror(xfp)) ? -1 : 0;
}